[PATCH 00/35] btrfs: add fscrypt support

[PATCH 00/35] btrfs: add fscrypt support

[Josef Bacik]

Hello,

This is the newly reworked fscrypt support for btrfs.  There have been a few
things changed since Sweet Tea's last post[1], and my RFC[2].  The changes from
Sweet Tea's patchset are mostly related to the fscrypt changes, but I'll detail
them here

- We have a fscrypt_extent_info struct that simply has the blk key in it and a
  nonce.
- We have a stripped down on disk context that just has what we need for
  extents.  At this time we only care about the nonce, everything else is
  supposed to match the owning inode.
- I've disabled everything except bog standard v2 policies to limit the
  complexity.
- Added the necessary hooks we needed for checksumming the encrypted bios.
- Reworked the on-disk stuff to be better described and accessed through
  helpers.
- Plumbed through the fscrypt_extent_info through everything to simplify the
  API calls we need from fscrypt.
- Instead of handling async key free'ing in fscrypt, handle the case where we're
  freeing extent_maps under the lock in a safe way.  This is cleaner than
  pushing this into fscrypt.
- Fixed a few things that fsstress uncovered in testing.

Changes to the fscrypt code since my RFC

- Took Eric's advice and added the policy and key to the extent context, this
  way if we want to in the future we could handle key changing.
- Added a helper to give us the fscrypt extent info context size.  We need the
  size ahead of time to setup the item properly.
- Fixed the blk crypto fallback not actually working with our process_bio
  callback.  Added a policy flag to make sure the checks work properly.
- Added some documentation.

Things left to do

- I still have to update fstests to deal with v2 only policies.  I haven't
  touched fstests at all yet, I've merely done my own rough testing with
  fsstress.
- Update the btrfs-progs patches.  This needs to be done to get the fstests
  stuff to work as well.
- fsverity still isn't encrypted.  I'm going to hit that next, it should be
  straightforward enough.

This is based on for-next from Dave's tree [3], but in case that moves between
now and then you can see my current branch here [4].  Thanks,

Josef

[1] https://lore.kernel.org/linux-fscrypt/cover.1693630890.git.sweettea-kernel@dorminy.me/
[2] https://lore.kernel.org/linux-btrfs/cover.1694738282.git.josef@toxicpanda.com/
[3] https://github.com/kdave/btrfs-devel/tree/for-next
[4] https://github.com/josefbacik/linux/tree/fscrypt

Josef Bacik (20):
  fscrypt: rename fscrypt_info => fscrypt_inode_info
  fscrypt: add per-extent encryption support
  fscrypt: disable all but standard v2 policies for extent encryption
  blk-crypto: add a process bio callback
  fscrypt: add documentation about extent encryption
  btrfs: add infrastructure for safe em freeing
  btrfs: add fscrypt_info and encryption_type to ordered_extent
  btrfs: plumb through setting the fscrypt_info for ordered extents
  btrfs: populate the ordered_extent with the fscrypt context
  btrfs: keep track of fscrypt info and orig_start for dio reads
  btrfs: add an optional encryption context to the end of file extents
  btrfs: pass through fscrypt_extent_info to the file extent helpers
  btrfs: pass the fscrypt_info through the replace extent infrastructure
  btrfs: implement the fscrypt extent encryption hooks
  btrfs: setup fscrypt_extent_info for new extents
  btrfs: populate ordered_extent with the orig offset
  btrfs: set the bio fscrypt context when applicable
  btrfs: add a bio argument to btrfs_csum_one_bio
  btrfs: add orig_logical to btrfs_bio
  btrfs: implement process_bio cb for fscrypt

Omar Sandoval (7):
  fscrypt: expose fscrypt_nokey_name
  btrfs: disable various operations on encrypted inodes
  btrfs: start using fscrypt hooks
  btrfs: add inode encryption contexts
  btrfs: add new FEATURE_INCOMPAT_ENCRYPT flag
  btrfs: adapt readdir for encrypted and nokey names
  btrfs: implement fscrypt ioctls

Sweet Tea Dorminy (8):
  btrfs: disable verity on encrypted inodes
  btrfs: handle nokey names.
  btrfs: add encryption to CONFIG_BTRFS_DEBUG
  btrfs: add get_devices hook for fscrypt
  btrfs: turn on inlinecrypt mount option for encrypt
  btrfs: set file extent encryption excplicitly
  btrfs: add fscrypt_info and encryption_type to extent_map
  btrfs: explicitly track file extent length for replace and drop

 Documentation/filesystems/fscrypt.rst |  36 ++
 block/blk-crypto-fallback.c           |  28 ++
 block/blk-crypto-profile.c            |   2 +
 block/blk-crypto.c                    |   6 +-
 fs/btrfs/Makefile                     |   1 +
 fs/btrfs/accessors.h                  |  50 +++
 fs/btrfs/bio.c                        |  45 ++-
 fs/btrfs/bio.h                        |   6 +
 fs/btrfs/btrfs_inode.h                |   3 +-
 fs/btrfs/compression.c                |   6 +
 fs/btrfs/ctree.h                      |   4 +
 fs/btrfs/defrag.c                     |  10 +-
 fs/btrfs/delayed-inode.c              |  29 +-
 fs/btrfs/delayed-inode.h              |   6 +-
 fs/btrfs/dir-item.c                   | 108 +++++-
 fs/btrfs/dir-item.h                   |  11 +-
 fs/btrfs/extent_io.c                  |  81 ++++-
 fs/btrfs/extent_io.h                  |   3 +
 fs/btrfs/extent_map.c                 | 106 +++++-
 fs/btrfs/extent_map.h                 |  12 +
 fs/btrfs/file-item.c                  |  17 +-
 fs/btrfs/file-item.h                  |   7 +-
 fs/btrfs/file.c                       |  16 +-
 fs/btrfs/fs.h                         |   3 +-
 fs/btrfs/fscrypt.c                    | 326 ++++++++++++++++++
 fs/btrfs/fscrypt.h                    |  95 +++++
 fs/btrfs/inode.c                      | 476 ++++++++++++++++++++------
 fs/btrfs/ioctl.c                      |  41 ++-
 fs/btrfs/ordered-data.c               |  26 +-
 fs/btrfs/ordered-data.h               |  21 +-
 fs/btrfs/reflink.c                    |   8 +
 fs/btrfs/root-tree.c                  |   8 +-
 fs/btrfs/root-tree.h                  |   2 +-
 fs/btrfs/super.c                      |  17 +
 fs/btrfs/sysfs.c                      |   6 +
 fs/btrfs/tree-checker.c               |  66 +++-
 fs/btrfs/tree-log.c                   |  26 +-
 fs/btrfs/verity.c                     |   3 +
 fs/crypto/crypto.c                    |  23 +-
 fs/crypto/fname.c                     |  45 +--
 fs/crypto/fscrypt_private.h           |  87 ++++-
 fs/crypto/hooks.c                     |   2 +-
 fs/crypto/inline_crypt.c              | 100 +++++-
 fs/crypto/keyring.c                   |   4 +-
 fs/crypto/keysetup.c                  | 190 +++++++++-
 fs/crypto/keysetup_v1.c               |  14 +-
 fs/crypto/policy.c                    |  70 +++-
 include/linux/blk-crypto-profile.h    |   7 +
 include/linux/blk-crypto.h            |   9 +-
 include/linux/fs.h                    |   4 +-
 include/linux/fscrypt.h               | 123 ++++++-
 include/uapi/linux/btrfs.h            |   1 +
 include/uapi/linux/btrfs_tree.h       |  35 +-
 53 files changed, 2144 insertions(+), 287 deletions(-)
 create mode 100644 fs/btrfs/fscrypt.c
 create mode 100644 fs/btrfs/fscrypt.h

-- 
2.41.0

[PATCH 01/35] fscrypt: rename fscrypt_info => fscrypt_inode_info

[Josef Bacik]

We are going to track per-extent information, so it'll be necessary to
distinguish between inode infos and extent infos.  Rename fscrypt_info
to fscrypt_inode_info, adjusting any lines that now exceed 80
characters.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/crypto/crypto.c          | 13 ++++++------
 fs/crypto/fname.c           |  6 +++---
 fs/crypto/fscrypt_private.h | 42 ++++++++++++++++++++-----------------
 fs/crypto/hooks.c           |  2 +-
 fs/crypto/inline_crypt.c    | 13 ++++++------
 fs/crypto/keyring.c         |  4 ++--
 fs/crypto/keysetup.c        | 38 +++++++++++++++++----------------
 fs/crypto/keysetup_v1.c     | 14 +++++++------
 fs/crypto/policy.c          | 11 +++++-----
 include/linux/fs.h          |  4 ++--
 include/linux/fscrypt.h     |  6 +++---
 11 files changed, 82 insertions(+), 71 deletions(-)

diff --git a/fs/crypto/crypto.c b/fs/crypto/crypto.c
index 6a837e4b80dc..2b2bb5740322 100644
--- a/fs/crypto/crypto.c
+++ b/fs/crypto/crypto.c
@@ -39,7 +39,7 @@ static mempool_t *fscrypt_bounce_page_pool = NULL;
 static struct workqueue_struct *fscrypt_read_workqueue;
 static DEFINE_MUTEX(fscrypt_init_mutex);
 
-struct kmem_cache *fscrypt_info_cachep;
+struct kmem_cache *fscrypt_inode_info_cachep;
 
 void fscrypt_enqueue_decrypt_work(struct work_struct *work)
 {
@@ -78,7 +78,7 @@ EXPORT_SYMBOL(fscrypt_free_bounce_page);
  * simply contain the lblk_num (e.g., IV_INO_LBLK_32).
  */
 void fscrypt_generate_iv(union fscrypt_iv *iv, u64 lblk_num,
-			 const struct fscrypt_info *ci)
+			 const struct fscrypt_inode_info *ci)
 {
 	u8 flags = fscrypt_policy_flags(&ci->ci_policy);
 
@@ -107,7 +107,7 @@ int fscrypt_crypt_block(const struct inode *inode, fscrypt_direction_t rw,
 	struct skcipher_request *req = NULL;
 	DECLARE_CRYPTO_WAIT(wait);
 	struct scatterlist dst, src;
-	struct fscrypt_info *ci = inode->i_crypt_info;
+	struct fscrypt_inode_info *ci = inode->i_crypt_info;
 	struct crypto_skcipher *tfm = ci->ci_enc_key.tfm;
 	int res = 0;
 
@@ -391,8 +391,9 @@ static int __init fscrypt_init(void)
 	if (!fscrypt_read_workqueue)
 		goto fail;
 
-	fscrypt_info_cachep = KMEM_CACHE(fscrypt_info, SLAB_RECLAIM_ACCOUNT);
-	if (!fscrypt_info_cachep)
+	fscrypt_inode_info_cachep = KMEM_CACHE(fscrypt_inode_info,
+					       SLAB_RECLAIM_ACCOUNT);
+	if (!fscrypt_inode_info_cachep)
 		goto fail_free_queue;
 
 	err = fscrypt_init_keyring();
@@ -402,7 +403,7 @@ static int __init fscrypt_init(void)
 	return 0;
 
 fail_free_info:
-	kmem_cache_destroy(fscrypt_info_cachep);
+	kmem_cache_destroy(fscrypt_inode_info_cachep);
 fail_free_queue:
 	destroy_workqueue(fscrypt_read_workqueue);
 fail:
diff --git a/fs/crypto/fname.c b/fs/crypto/fname.c
index 6eae3f12ad50..7b3fc189593a 100644
--- a/fs/crypto/fname.c
+++ b/fs/crypto/fname.c
@@ -100,7 +100,7 @@ int fscrypt_fname_encrypt(const struct inode *inode, const struct qstr *iname,
 {
 	struct skcipher_request *req = NULL;
 	DECLARE_CRYPTO_WAIT(wait);
-	const struct fscrypt_info *ci = inode->i_crypt_info;
+	const struct fscrypt_inode_info *ci = inode->i_crypt_info;
 	struct crypto_skcipher *tfm = ci->ci_enc_key.tfm;
 	union fscrypt_iv iv;
 	struct scatterlist sg;
@@ -157,7 +157,7 @@ static int fname_decrypt(const struct inode *inode,
 	struct skcipher_request *req = NULL;
 	DECLARE_CRYPTO_WAIT(wait);
 	struct scatterlist src_sg, dst_sg;
-	const struct fscrypt_info *ci = inode->i_crypt_info;
+	const struct fscrypt_inode_info *ci = inode->i_crypt_info;
 	struct crypto_skcipher *tfm = ci->ci_enc_key.tfm;
 	union fscrypt_iv iv;
 	int res;
@@ -568,7 +568,7 @@ EXPORT_SYMBOL_GPL(fscrypt_match_name);
  */
 u64 fscrypt_fname_siphash(const struct inode *dir, const struct qstr *name)
 {
-	const struct fscrypt_info *ci = dir->i_crypt_info;
+	const struct fscrypt_inode_info *ci = dir->i_crypt_info;
 
 	WARN_ON_ONCE(!ci->ci_dirhash_key_initialized);
 
diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
index 2d63da48635a..b982073d1fe2 100644
--- a/fs/crypto/fscrypt_private.h
+++ b/fs/crypto/fscrypt_private.h
@@ -189,18 +189,21 @@ struct fscrypt_prepared_key {
 };
 
 /*
- * fscrypt_info - the "encryption key" for an inode
+ * fscrypt_inode_info - the "encryption key" for an inode
  *
  * When an encrypted file's key is made available, an instance of this struct is
  * allocated and stored in ->i_crypt_info.  Once created, it remains until the
  * inode is evicted.
  */
-struct fscrypt_info {
+struct fscrypt_inode_info {
 
 	/* The key in a form prepared for actual encryption/decryption */
 	struct fscrypt_prepared_key ci_enc_key;
 
-	/* True if ci_enc_key should be freed when this fscrypt_info is freed */
+	/*
+	 * True if ci_enc_key should be freed when this fscrypt_inode_info is
+	 * freed
+	 */
 	bool ci_owns_key;
 
 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
@@ -263,7 +266,7 @@ typedef enum {
 } fscrypt_direction_t;
 
 /* crypto.c */
-extern struct kmem_cache *fscrypt_info_cachep;
+extern struct kmem_cache *fscrypt_inode_info_cachep;
 int fscrypt_initialize(struct super_block *sb);
 int fscrypt_crypt_block(const struct inode *inode, fscrypt_direction_t rw,
 			u64 lblk_num, struct page *src_page,
@@ -294,7 +297,7 @@ union fscrypt_iv {
 };
 
 void fscrypt_generate_iv(union fscrypt_iv *iv, u64 lblk_num,
-			 const struct fscrypt_info *ci);
+			 const struct fscrypt_inode_info *ci);
 
 /* fname.c */
 bool __fscrypt_fname_encrypted_size(const union fscrypt_policy *policy,
@@ -332,17 +335,17 @@ void fscrypt_destroy_hkdf(struct fscrypt_hkdf *hkdf);
 
 /* inline_crypt.c */
 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
-int fscrypt_select_encryption_impl(struct fscrypt_info *ci);
+int fscrypt_select_encryption_impl(struct fscrypt_inode_info *ci);
 
 static inline bool
-fscrypt_using_inline_encryption(const struct fscrypt_info *ci)
+fscrypt_using_inline_encryption(const struct fscrypt_inode_info *ci)
 {
 	return ci->ci_inlinecrypt;
 }
 
 int fscrypt_prepare_inline_crypt_key(struct fscrypt_prepared_key *prep_key,
 				     const u8 *raw_key,
-				     const struct fscrypt_info *ci);
+				     const struct fscrypt_inode_info *ci);
 
 void fscrypt_destroy_inline_crypt_key(struct super_block *sb,
 				      struct fscrypt_prepared_key *prep_key);
@@ -353,7 +356,7 @@ void fscrypt_destroy_inline_crypt_key(struct super_block *sb,
  */
 static inline bool
 fscrypt_is_key_prepared(struct fscrypt_prepared_key *prep_key,
-			const struct fscrypt_info *ci)
+			const struct fscrypt_inode_info *ci)
 {
 	/*
 	 * The two smp_load_acquire()'s here pair with the smp_store_release()'s
@@ -370,13 +373,13 @@ fscrypt_is_key_prepared(struct fscrypt_prepared_key *prep_key,
 
 #else /* CONFIG_FS_ENCRYPTION_INLINE_CRYPT */
 
-static inline int fscrypt_select_encryption_impl(struct fscrypt_info *ci)
+static inline int fscrypt_select_encryption_impl(struct fscrypt_inode_info *ci)
 {
 	return 0;
 }
 
 static inline bool
-fscrypt_using_inline_encryption(const struct fscrypt_info *ci)
+fscrypt_using_inline_encryption(const struct fscrypt_inode_info *ci)
 {
 	return false;
 }
@@ -384,7 +387,7 @@ fscrypt_using_inline_encryption(const struct fscrypt_info *ci)
 static inline int
 fscrypt_prepare_inline_crypt_key(struct fscrypt_prepared_key *prep_key,
 				 const u8 *raw_key,
-				 const struct fscrypt_info *ci)
+				 const struct fscrypt_inode_info *ci)
 {
 	WARN_ON_ONCE(1);
 	return -EOPNOTSUPP;
@@ -398,7 +401,7 @@ fscrypt_destroy_inline_crypt_key(struct super_block *sb,
 
 static inline bool
 fscrypt_is_key_prepared(struct fscrypt_prepared_key *prep_key,
-			const struct fscrypt_info *ci)
+			const struct fscrypt_inode_info *ci)
 {
 	return smp_load_acquire(&prep_key->tfm) != NULL;
 }
@@ -598,17 +601,18 @@ struct fscrypt_mode {
 extern struct fscrypt_mode fscrypt_modes[];
 
 int fscrypt_prepare_key(struct fscrypt_prepared_key *prep_key,
-			const u8 *raw_key, const struct fscrypt_info *ci);
+			const u8 *raw_key, const struct fscrypt_inode_info *ci);
 
 void fscrypt_destroy_prepared_key(struct super_block *sb,
 				  struct fscrypt_prepared_key *prep_key);
 
-int fscrypt_set_per_file_enc_key(struct fscrypt_info *ci, const u8 *raw_key);
+int fscrypt_set_per_file_enc_key(struct fscrypt_inode_info *ci,
+				 const u8 *raw_key);
 
-int fscrypt_derive_dirhash_key(struct fscrypt_info *ci,
+int fscrypt_derive_dirhash_key(struct fscrypt_inode_info *ci,
 			       const struct fscrypt_master_key *mk);
 
-void fscrypt_hash_inode_number(struct fscrypt_info *ci,
+void fscrypt_hash_inode_number(struct fscrypt_inode_info *ci,
 			       const struct fscrypt_master_key *mk);
 
 int fscrypt_get_encryption_info(struct inode *inode, bool allow_unsupported);
@@ -643,10 +647,10 @@ static inline int fscrypt_require_key(struct inode *inode)
 
 void fscrypt_put_direct_key(struct fscrypt_direct_key *dk);
 
-int fscrypt_setup_v1_file_key(struct fscrypt_info *ci,
+int fscrypt_setup_v1_file_key(struct fscrypt_inode_info *ci,
 			      const u8 *raw_master_key);
 
-int fscrypt_setup_v1_file_key_via_subscribed_keyrings(struct fscrypt_info *ci);
+int fscrypt_setup_v1_file_key_via_subscribed_keyrings(struct fscrypt_inode_info *ci);
 
 /* policy.c */
 
diff --git a/fs/crypto/hooks.c b/fs/crypto/hooks.c
index 6238dbcadcad..85d2975b69b7 100644
--- a/fs/crypto/hooks.c
+++ b/fs/crypto/hooks.c
@@ -169,7 +169,7 @@ EXPORT_SYMBOL_GPL(__fscrypt_prepare_setattr);
 int fscrypt_prepare_setflags(struct inode *inode,
 			     unsigned int oldflags, unsigned int flags)
 {
-	struct fscrypt_info *ci;
+	struct fscrypt_inode_info *ci;
 	struct fscrypt_master_key *mk;
 	int err;
 
diff --git a/fs/crypto/inline_crypt.c b/fs/crypto/inline_crypt.c
index 8bfb3ce86476..3cfb04b8b64f 100644
--- a/fs/crypto/inline_crypt.c
+++ b/fs/crypto/inline_crypt.c
@@ -39,7 +39,7 @@ static struct block_device **fscrypt_get_devices(struct super_block *sb,
 	return devs;
 }
 
-static unsigned int fscrypt_get_dun_bytes(const struct fscrypt_info *ci)
+static unsigned int fscrypt_get_dun_bytes(const struct fscrypt_inode_info *ci)
 {
 	struct super_block *sb = ci->ci_inode->i_sb;
 	unsigned int flags = fscrypt_policy_flags(&ci->ci_policy);
@@ -90,7 +90,7 @@ static void fscrypt_log_blk_crypto_impl(struct fscrypt_mode *mode,
 }
 
 /* Enable inline encryption for this file if supported. */
-int fscrypt_select_encryption_impl(struct fscrypt_info *ci)
+int fscrypt_select_encryption_impl(struct fscrypt_inode_info *ci)
 {
 	const struct inode *inode = ci->ci_inode;
 	struct super_block *sb = inode->i_sb;
@@ -152,7 +152,7 @@ int fscrypt_select_encryption_impl(struct fscrypt_info *ci)
 
 int fscrypt_prepare_inline_crypt_key(struct fscrypt_prepared_key *prep_key,
 				     const u8 *raw_key,
-				     const struct fscrypt_info *ci)
+				     const struct fscrypt_inode_info *ci)
 {
 	const struct inode *inode = ci->ci_inode;
 	struct super_block *sb = inode->i_sb;
@@ -232,7 +232,8 @@ bool __fscrypt_inode_uses_inline_crypto(const struct inode *inode)
 }
 EXPORT_SYMBOL_GPL(__fscrypt_inode_uses_inline_crypto);
 
-static void fscrypt_generate_dun(const struct fscrypt_info *ci, u64 lblk_num,
+static void fscrypt_generate_dun(const struct fscrypt_inode_info *ci,
+				 u64 lblk_num,
 				 u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE])
 {
 	union fscrypt_iv iv;
@@ -265,7 +266,7 @@ static void fscrypt_generate_dun(const struct fscrypt_info *ci, u64 lblk_num,
 void fscrypt_set_bio_crypt_ctx(struct bio *bio, const struct inode *inode,
 			       u64 first_lblk, gfp_t gfp_mask)
 {
-	const struct fscrypt_info *ci;
+	const struct fscrypt_inode_info *ci;
 	u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE];
 
 	if (!fscrypt_inode_uses_inline_crypto(inode))
@@ -456,7 +457,7 @@ EXPORT_SYMBOL_GPL(fscrypt_dio_supported);
  */
 u64 fscrypt_limit_io_blocks(const struct inode *inode, u64 lblk, u64 nr_blocks)
 {
-	const struct fscrypt_info *ci;
+	const struct fscrypt_inode_info *ci;
 	u32 dun;
 
 	if (!fscrypt_inode_uses_inline_crypto(inode))
diff --git a/fs/crypto/keyring.c b/fs/crypto/keyring.c
index 7cbb1fd872ac..a51fa6a33de1 100644
--- a/fs/crypto/keyring.c
+++ b/fs/crypto/keyring.c
@@ -867,7 +867,7 @@ static void shrink_dcache_inode(struct inode *inode)
 
 static void evict_dentries_for_decrypted_inodes(struct fscrypt_master_key *mk)
 {
-	struct fscrypt_info *ci;
+	struct fscrypt_inode_info *ci;
 	struct inode *inode;
 	struct inode *toput_inode = NULL;
 
@@ -917,7 +917,7 @@ static int check_for_busy_inodes(struct super_block *sb,
 		/* select an example file to show for debugging purposes */
 		struct inode *inode =
 			list_first_entry(&mk->mk_decrypted_inodes,
-					 struct fscrypt_info,
+					 struct fscrypt_inode_info,
 					 ci_master_key_link)->ci_inode;
 		ino = inode->i_ino;
 	}
diff --git a/fs/crypto/keysetup.c b/fs/crypto/keysetup.c
index 361f41ef46c7..cbcbe582737e 100644
--- a/fs/crypto/keysetup.c
+++ b/fs/crypto/keysetup.c
@@ -148,7 +148,7 @@ fscrypt_allocate_skcipher(struct fscrypt_mode *mode, const u8 *raw_key,
  * and IV generation method (@ci->ci_policy.flags).
  */
 int fscrypt_prepare_key(struct fscrypt_prepared_key *prep_key,
-			const u8 *raw_key, const struct fscrypt_info *ci)
+			const u8 *raw_key, const struct fscrypt_inode_info *ci)
 {
 	struct crypto_skcipher *tfm;
 
@@ -178,13 +178,14 @@ void fscrypt_destroy_prepared_key(struct super_block *sb,
 }
 
 /* Given a per-file encryption key, set up the file's crypto transform object */
-int fscrypt_set_per_file_enc_key(struct fscrypt_info *ci, const u8 *raw_key)
+int fscrypt_set_per_file_enc_key(struct fscrypt_inode_info *ci,
+				 const u8 *raw_key)
 {
 	ci->ci_owns_key = true;
 	return fscrypt_prepare_key(&ci->ci_enc_key, raw_key, ci);
 }
 
-static int setup_per_mode_enc_key(struct fscrypt_info *ci,
+static int setup_per_mode_enc_key(struct fscrypt_inode_info *ci,
 				  struct fscrypt_master_key *mk,
 				  struct fscrypt_prepared_key *keys,
 				  u8 hkdf_context, bool include_fs_uuid)
@@ -265,7 +266,7 @@ static int fscrypt_derive_siphash_key(const struct fscrypt_master_key *mk,
 	return 0;
 }
 
-int fscrypt_derive_dirhash_key(struct fscrypt_info *ci,
+int fscrypt_derive_dirhash_key(struct fscrypt_inode_info *ci,
 			       const struct fscrypt_master_key *mk)
 {
 	int err;
@@ -279,7 +280,7 @@ int fscrypt_derive_dirhash_key(struct fscrypt_info *ci,
 	return 0;
 }
 
-void fscrypt_hash_inode_number(struct fscrypt_info *ci,
+void fscrypt_hash_inode_number(struct fscrypt_inode_info *ci,
 			       const struct fscrypt_master_key *mk)
 {
 	WARN_ON_ONCE(ci->ci_inode->i_ino == 0);
@@ -289,7 +290,7 @@ void fscrypt_hash_inode_number(struct fscrypt_info *ci,
 					      &mk->mk_ino_hash_key);
 }
 
-static int fscrypt_setup_iv_ino_lblk_32_key(struct fscrypt_info *ci,
+static int fscrypt_setup_iv_ino_lblk_32_key(struct fscrypt_inode_info *ci,
 					    struct fscrypt_master_key *mk)
 {
 	int err;
@@ -329,7 +330,7 @@ static int fscrypt_setup_iv_ino_lblk_32_key(struct fscrypt_info *ci,
 	return 0;
 }
 
-static int fscrypt_setup_v2_file_key(struct fscrypt_info *ci,
+static int fscrypt_setup_v2_file_key(struct fscrypt_inode_info *ci,
 				     struct fscrypt_master_key *mk,
 				     bool need_dirhash_key)
 {
@@ -404,7 +405,7 @@ static int fscrypt_setup_v2_file_key(struct fscrypt_info *ci,
  * still allow 512-bit master keys if the user chooses to use them, though.)
  */
 static bool fscrypt_valid_master_key_size(const struct fscrypt_master_key *mk,
-					  const struct fscrypt_info *ci)
+					  const struct fscrypt_inode_info *ci)
 {
 	unsigned int min_keysize;
 
@@ -430,11 +431,12 @@ static bool fscrypt_valid_master_key_size(const struct fscrypt_master_key *mk,
  *
  * If the master key is found in the filesystem-level keyring, then it is
  * returned in *mk_ret with its semaphore read-locked.  This is needed to ensure
- * that only one task links the fscrypt_info into ->mk_decrypted_inodes (as
- * multiple tasks may race to create an fscrypt_info for the same inode), and to
- * synchronize the master key being removed with a new inode starting to use it.
+ * that only one task links the fscrypt_inode_info into ->mk_decrypted_inodes
+ * (as multiple tasks may race to create an fscrypt_inode_info for the same
+ * inode), and to synchronize the master key being removed with a new inode
+ * starting to use it.
  */
-static int setup_file_encryption_key(struct fscrypt_info *ci,
+static int setup_file_encryption_key(struct fscrypt_inode_info *ci,
 				     bool need_dirhash_key,
 				     struct fscrypt_master_key **mk_ret)
 {
@@ -519,7 +521,7 @@ static int setup_file_encryption_key(struct fscrypt_info *ci,
 	return err;
 }
 
-static void put_crypt_info(struct fscrypt_info *ci)
+static void put_crypt_info(struct fscrypt_inode_info *ci)
 {
 	struct fscrypt_master_key *mk;
 
@@ -546,7 +548,7 @@ static void put_crypt_info(struct fscrypt_info *ci)
 		fscrypt_put_master_key_activeref(ci->ci_inode->i_sb, mk);
 	}
 	memzero_explicit(ci, sizeof(*ci));
-	kmem_cache_free(fscrypt_info_cachep, ci);
+	kmem_cache_free(fscrypt_inode_info_cachep, ci);
 }
 
 static int
@@ -555,7 +557,7 @@ fscrypt_setup_encryption_info(struct inode *inode,
 			      const u8 nonce[FSCRYPT_FILE_NONCE_SIZE],
 			      bool need_dirhash_key)
 {
-	struct fscrypt_info *crypt_info;
+	struct fscrypt_inode_info *crypt_info;
 	struct fscrypt_mode *mode;
 	struct fscrypt_master_key *mk = NULL;
 	int res;
@@ -564,7 +566,7 @@ fscrypt_setup_encryption_info(struct inode *inode,
 	if (res)
 		return res;
 
-	crypt_info = kmem_cache_zalloc(fscrypt_info_cachep, GFP_KERNEL);
+	crypt_info = kmem_cache_zalloc(fscrypt_inode_info_cachep, GFP_KERNEL);
 	if (!crypt_info)
 		return -ENOMEM;
 
@@ -735,7 +737,7 @@ EXPORT_SYMBOL_GPL(fscrypt_prepare_new_inode);
  * fscrypt_put_encryption_info() - free most of an inode's fscrypt data
  * @inode: an inode being evicted
  *
- * Free the inode's fscrypt_info.  Filesystems must call this when the inode is
+ * Free the inode's fscrypt_inode_info.  Filesystems must call this when the inode is
  * being evicted.  An RCU grace period need not have elapsed yet.
  */
 void fscrypt_put_encryption_info(struct inode *inode)
@@ -773,7 +775,7 @@ EXPORT_SYMBOL(fscrypt_free_inode);
  */
 int fscrypt_drop_inode(struct inode *inode)
 {
-	const struct fscrypt_info *ci = fscrypt_get_info(inode);
+	const struct fscrypt_inode_info *ci = fscrypt_get_info(inode);
 
 	/*
 	 * If ci is NULL, then the inode doesn't have an encryption key set up
diff --git a/fs/crypto/keysetup_v1.c b/fs/crypto/keysetup_v1.c
index 75dabd9b27f9..b1e36494facf 100644
--- a/fs/crypto/keysetup_v1.c
+++ b/fs/crypto/keysetup_v1.c
@@ -178,7 +178,8 @@ void fscrypt_put_direct_key(struct fscrypt_direct_key *dk)
  */
 static struct fscrypt_direct_key *
 find_or_insert_direct_key(struct fscrypt_direct_key *to_insert,
-			  const u8 *raw_key, const struct fscrypt_info *ci)
+			  const u8 *raw_key,
+			  const struct fscrypt_inode_info *ci)
 {
 	unsigned long hash_key;
 	struct fscrypt_direct_key *dk;
@@ -218,7 +219,7 @@ find_or_insert_direct_key(struct fscrypt_direct_key *to_insert,
 
 /* Prepare to encrypt directly using the master key in the given mode */
 static struct fscrypt_direct_key *
-fscrypt_get_direct_key(const struct fscrypt_info *ci, const u8 *raw_key)
+fscrypt_get_direct_key(const struct fscrypt_inode_info *ci, const u8 *raw_key)
 {
 	struct fscrypt_direct_key *dk;
 	int err;
@@ -250,7 +251,7 @@ fscrypt_get_direct_key(const struct fscrypt_info *ci, const u8 *raw_key)
 }
 
 /* v1 policy, DIRECT_KEY: use the master key directly */
-static int setup_v1_file_key_direct(struct fscrypt_info *ci,
+static int setup_v1_file_key_direct(struct fscrypt_inode_info *ci,
 				    const u8 *raw_master_key)
 {
 	struct fscrypt_direct_key *dk;
@@ -264,7 +265,7 @@ static int setup_v1_file_key_direct(struct fscrypt_info *ci,
 }
 
 /* v1 policy, !DIRECT_KEY: derive the file's encryption key */
-static int setup_v1_file_key_derived(struct fscrypt_info *ci,
+static int setup_v1_file_key_derived(struct fscrypt_inode_info *ci,
 				     const u8 *raw_master_key)
 {
 	u8 *derived_key;
@@ -289,7 +290,8 @@ static int setup_v1_file_key_derived(struct fscrypt_info *ci,
 	return err;
 }
 
-int fscrypt_setup_v1_file_key(struct fscrypt_info *ci, const u8 *raw_master_key)
+int fscrypt_setup_v1_file_key(struct fscrypt_inode_info *ci,
+			      const u8 *raw_master_key)
 {
 	if (ci->ci_policy.v1.flags & FSCRYPT_POLICY_FLAG_DIRECT_KEY)
 		return setup_v1_file_key_direct(ci, raw_master_key);
@@ -297,7 +299,7 @@ int fscrypt_setup_v1_file_key(struct fscrypt_info *ci, const u8 *raw_master_key)
 		return setup_v1_file_key_derived(ci, raw_master_key);
 }
 
-int fscrypt_setup_v1_file_key_via_subscribed_keyrings(struct fscrypt_info *ci)
+int fscrypt_setup_v1_file_key_via_subscribed_keyrings(struct fscrypt_inode_info *ci)
 {
 	struct key *key;
 	const struct fscrypt_key *payload;
diff --git a/fs/crypto/policy.c b/fs/crypto/policy.c
index f4456ecb3f87..aa94bfe6c172 100644
--- a/fs/crypto/policy.c
+++ b/fs/crypto/policy.c
@@ -405,7 +405,7 @@ int fscrypt_policy_from_context(union fscrypt_policy *policy_u,
 /* Retrieve an inode's encryption policy */
 static int fscrypt_get_policy(struct inode *inode, union fscrypt_policy *policy)
 {
-	const struct fscrypt_info *ci;
+	const struct fscrypt_inode_info *ci;
 	union fscrypt_context ctx;
 	int ret;
 
@@ -647,8 +647,9 @@ int fscrypt_has_permitted_context(struct inode *parent, struct inode *child)
 
 	/*
 	 * Both parent and child are encrypted, so verify they use the same
-	 * encryption policy.  Compare the fscrypt_info structs if the keys are
-	 * available, otherwise retrieve and compare the fscrypt_contexts.
+	 * encryption policy.  Compare the fscrypt_inode_info structs if the
+	 * keys are available, otherwise retrieve and compare the
+	 * fscrypt_contexts.
 	 *
 	 * Note that the fscrypt_context retrieval will be required frequently
 	 * when accessing an encrypted directory tree without the key.
@@ -717,7 +718,7 @@ const union fscrypt_policy *fscrypt_policy_to_inherit(struct inode *dir)
  */
 int fscrypt_context_for_new_inode(void *ctx, struct inode *inode)
 {
-	struct fscrypt_info *ci = inode->i_crypt_info;
+	struct fscrypt_inode_info *ci = inode->i_crypt_info;
 
 	BUILD_BUG_ON(sizeof(union fscrypt_context) !=
 			FSCRYPT_SET_CONTEXT_MAX_SIZE);
@@ -742,7 +743,7 @@ EXPORT_SYMBOL_GPL(fscrypt_context_for_new_inode);
  */
 int fscrypt_set_context(struct inode *inode, void *fs_data)
 {
-	struct fscrypt_info *ci = inode->i_crypt_info;
+	struct fscrypt_inode_info *ci = inode->i_crypt_info;
 	union fscrypt_context ctx;
 	int ctxsize;
 
diff --git a/include/linux/fs.h b/include/linux/fs.h
index b528f063e8ff..a3df96736473 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -67,7 +67,7 @@ struct swap_info_struct;
 struct seq_file;
 struct workqueue_struct;
 struct iov_iter;
-struct fscrypt_info;
+struct fscrypt_inode_info;
 struct fscrypt_operations;
 struct fsverity_info;
 struct fsverity_operations;
@@ -738,7 +738,7 @@ struct inode {
 #endif
 
 #ifdef CONFIG_FS_ENCRYPTION
-	struct fscrypt_info	*i_crypt_info;
+	struct fscrypt_inode_info	*i_crypt_info;
 #endif
 
 #ifdef CONFIG_FS_VERITY
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index c895b12737a1..ece426ac1d73 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -31,7 +31,7 @@
 #define FSCRYPT_CONTENTS_ALIGNMENT 16
 
 union fscrypt_policy;
-struct fscrypt_info;
+struct fscrypt_inode_info;
 struct fs_parameter;
 struct seq_file;
 
@@ -178,7 +178,7 @@ struct fscrypt_operations {
 					     unsigned int *num_devs);
 };
 
-static inline struct fscrypt_info *fscrypt_get_info(const struct inode *inode)
+static inline struct fscrypt_inode_info *fscrypt_get_info(const struct inode *inode)
 {
 	/*
 	 * Pairs with the cmpxchg_release() in fscrypt_setup_encryption_info().
@@ -390,7 +390,7 @@ static inline void fscrypt_set_ops(struct super_block *sb,
 }
 #else  /* !CONFIG_FS_ENCRYPTION */
 
-static inline struct fscrypt_info *fscrypt_get_info(const struct inode *inode)
+static inline struct fscrypt_inode_info *fscrypt_get_info(const struct inode *inode)
 {
 	return NULL;
 }
-- 
2.41.0

[PATCH 02/35] fscrypt: add per-extent encryption support

[Josef Bacik]

This adds the code necessary for per-extent encryption.  We will store a
nonce for every extent we create, and then use the inode's policy and
the extents nonce to derive a per-extent key.

This is meant to be flexible, if we choose to expand the on-disk extent
information in the future we have a version number we can use to change
what exists on disk.

The file system indicates it wants to use per-extent encryption by
setting s_cop->set_extent_context.  This also requires the use of inline
block encryption.

The support is relatively straightforward, the only "extra" bit is we're
deriving a per-extent key to use for the encryption, the inode still
controls the policy and access to the master key.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/crypto/crypto.c          |  10 ++-
 fs/crypto/fscrypt_private.h |  45 +++++++++++
 fs/crypto/inline_crypt.c    |  84 ++++++++++++++++++++
 fs/crypto/keysetup.c        | 152 ++++++++++++++++++++++++++++++++++++
 fs/crypto/policy.c          |  47 +++++++++++
 include/linux/fscrypt.h     |  66 ++++++++++++++++
 6 files changed, 403 insertions(+), 1 deletion(-)

diff --git a/fs/crypto/crypto.c b/fs/crypto/crypto.c
index 2b2bb5740322..e3ba06cb4082 100644
--- a/fs/crypto/crypto.c
+++ b/fs/crypto/crypto.c
@@ -40,6 +40,7 @@ static struct workqueue_struct *fscrypt_read_workqueue;
 static DEFINE_MUTEX(fscrypt_init_mutex);
 
 struct kmem_cache *fscrypt_inode_info_cachep;
+struct kmem_cache *fscrypt_extent_info_cachep;
 
 void fscrypt_enqueue_decrypt_work(struct work_struct *work)
 {
@@ -396,12 +397,19 @@ static int __init fscrypt_init(void)
 	if (!fscrypt_inode_info_cachep)
 		goto fail_free_queue;
 
+	fscrypt_extent_info_cachep = KMEM_CACHE(fscrypt_extent_info,
+						SLAB_RECLAIM_ACCOUNT);
+	if (!fscrypt_extent_info_cachep)
+		goto fail_free_info;
+
 	err = fscrypt_init_keyring();
 	if (err)
-		goto fail_free_info;
+		goto fail_free_extent_info;
 
 	return 0;
 
+fail_free_extent_info:
+	kmem_cache_destroy(fscrypt_extent_info_cachep);
 fail_free_info:
 	kmem_cache_destroy(fscrypt_inode_info_cachep);
 fail_free_queue:
diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
index b982073d1fe2..a7e902813cde 100644
--- a/fs/crypto/fscrypt_private.h
+++ b/fs/crypto/fscrypt_private.h
@@ -30,6 +30,8 @@
 #define FSCRYPT_CONTEXT_V1	1
 #define FSCRYPT_CONTEXT_V2	2
 
+#define FSCRYPT_EXTENT_CONTEXT_V1	1
+
 /* Keep this in sync with include/uapi/linux/fscrypt.h */
 #define FSCRYPT_MODE_MAX	FSCRYPT_MODE_AES_256_HCTR2
 
@@ -52,6 +54,28 @@ struct fscrypt_context_v2 {
 	u8 nonce[FSCRYPT_FILE_NONCE_SIZE];
 };
 
+/*
+ * fscrypt_extent_context - the encryption context of an extent
+ *
+ * This is the on-disk information stored for an extent.  The policy and
+ * relevante information is stored in the inode, the per-extent information is
+ * simply the nonce that's used in as KDF input in conjunction with the inode
+ * context to derive a per-extent key for encryption.
+ *
+ * At this point the master_key_identifier exists only for possible future
+ * expansion.  This will allow for an inode to have extents with multiple master
+ * keys, although sharing the same encryption mode.  This would be for re-keying
+ * or for reflinking between two differently encrypted inodes.  For now the
+ * master_key_descriptor must match the inode's, and we'll be using the inode's
+ * for all key derivation.
+ */
+struct fscrypt_extent_context {
+	u8 version; /* FSCRYPT_EXTENT_CONTEXT_V2 */
+	u8 encryption_mode;
+	u8 master_key_identifier[FSCRYPT_KEY_IDENTIFIER_SIZE];
+	u8 nonce[FSCRYPT_FILE_NONCE_SIZE];
+};
+
 /*
  * fscrypt_context - the encryption context of an inode
  *
@@ -260,6 +284,25 @@ struct fscrypt_inode_info {
 	u32 ci_hashed_ino;
 };
 
+/*
+ * fscrypt_extent_info - the "encryption key" for an extent.
+ *
+ * This contains the dervied key for the given extent and the nonce for the
+ * extent.
+ */
+struct fscrypt_extent_info {
+	refcount_t refs;
+
+	/* The derived key for this extent. */
+	struct fscrypt_prepared_key prep_key;
+
+	/* The super block that this extent belongs to. */
+	struct super_block *sb;
+
+	/* This is the extents nonce, loaded from the fscrypt_extent_context */
+	u8 nonce[FSCRYPT_FILE_NONCE_SIZE];
+};
+
 typedef enum {
 	FS_DECRYPT = 0,
 	FS_ENCRYPT,
@@ -267,6 +310,7 @@ typedef enum {
 
 /* crypto.c */
 extern struct kmem_cache *fscrypt_inode_info_cachep;
+extern struct kmem_cache *fscrypt_extent_info_cachep;
 int fscrypt_initialize(struct super_block *sb);
 int fscrypt_crypt_block(const struct inode *inode, fscrypt_direction_t rw,
 			u64 lblk_num, struct page *src_page,
@@ -326,6 +370,7 @@ int fscrypt_init_hkdf(struct fscrypt_hkdf *hkdf, const u8 *master_key,
 #define HKDF_CONTEXT_DIRHASH_KEY	5 /* info=file_nonce		*/
 #define HKDF_CONTEXT_IV_INO_LBLK_32_KEY	6 /* info=mode_num||fs_uuid	*/
 #define HKDF_CONTEXT_INODE_HASH_KEY	7 /* info=<empty>		*/
+#define HKDF_CONTEXT_PER_EXTENT_ENC_KEY	8 /* info=extent_nonce		*/
 
 int fscrypt_hkdf_expand(const struct fscrypt_hkdf *hkdf, u8 context,
 			const u8 *info, unsigned int infolen,
diff --git a/fs/crypto/inline_crypt.c b/fs/crypto/inline_crypt.c
index 3cfb04b8b64f..21e1851d4ba7 100644
--- a/fs/crypto/inline_crypt.c
+++ b/fs/crypto/inline_crypt.c
@@ -278,6 +278,40 @@ void fscrypt_set_bio_crypt_ctx(struct bio *bio, const struct inode *inode,
 }
 EXPORT_SYMBOL_GPL(fscrypt_set_bio_crypt_ctx);
 
+/**
+ * fscrypt_set_bio_crypt_ctx() - prepare a file contents bio for inline crypto
+ * @bio: a bio which will eventually be submitted to the file
+ * @inode: the file's inode
+ * @ei: the extent's crypto info
+ * @first_lblk: the first file logical block number in the I/O
+ * @gfp_mask: memory allocation flags - these must be a waiting mask so that
+ *					bio_crypt_set_ctx can't fail.
+ *
+ * If the contents of the file should be encrypted (or decrypted) with inline
+ * encryption, then assign the appropriate encryption context to the bio.
+ *
+ * Normally the bio should be newly allocated (i.e. no pages added yet), as
+ * otherwise fscrypt_mergeable_bio() won't work as intended.
+ *
+ * The encryption context will be freed automatically when the bio is freed.
+ */
+void fscrypt_set_bio_crypt_ctx_from_extent(struct bio *bio,
+					   const struct inode *inode,
+					   const struct fscrypt_extent_info *ei,
+					   u64 first_lblk, gfp_t gfp_mask)
+{
+	const struct fscrypt_inode_info *ci;
+	u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE];
+
+	if (!fscrypt_inode_uses_inline_crypto(inode))
+		return;
+	ci = inode->i_crypt_info;
+
+	fscrypt_generate_dun(ci, first_lblk, dun);
+	bio_crypt_set_ctx(bio, ei->prep_key.blk_key, dun, gfp_mask);
+}
+EXPORT_SYMBOL_GPL(fscrypt_set_bio_crypt_ctx_from_extent);
+
 /* Extract the inode and logical block number from a buffer_head. */
 static bool bh_get_inode_and_lblk_num(const struct buffer_head *bh,
 				      const struct inode **inode_ret,
@@ -369,6 +403,56 @@ bool fscrypt_mergeable_bio(struct bio *bio, const struct inode *inode,
 }
 EXPORT_SYMBOL_GPL(fscrypt_mergeable_bio);
 
+/**
+ * fscrypt_mergeable_extent_bio() - test whether data can be added to a bio
+ * @bio: the bio being built up
+ * @inode: the inode for the next part of the I/O
+ * @ei: the fscrypt_extent_info for this extent
+ * @next_lblk: the next file logical block number in the I/O
+ *
+ * When building a bio which may contain data which should undergo inline
+ * encryption (or decryption) via fscrypt, filesystems should call this function
+ * to ensure that the resulting bio contains only contiguous data unit numbers.
+ * This will return false if the next part of the I/O cannot be merged with the
+ * bio because either the encryption key would be different or the encryption
+ * data unit numbers would be discontiguous.
+ *
+ * fscrypt_set_bio_crypt_ctx_from_extent() must have already been called on the
+ * bio.
+ *
+ * This function isn't required in cases where crypto-mergeability is ensured in
+ * another way, such as I/O targeting only a single file (and thus a single key)
+ * combined with fscrypt_limit_io_blocks() to ensure DUN contiguity.
+ *
+ * Return: true iff the I/O is mergeable
+ */
+bool fscrypt_mergeable_extent_bio(struct bio *bio, const struct inode *inode,
+				  const struct fscrypt_extent_info *ei,
+				  u64 next_lblk)
+{
+	const struct bio_crypt_ctx *bc = bio->bi_crypt_context;
+	u64 next_dun[BLK_CRYPTO_DUN_ARRAY_SIZE];
+
+	if (!ei)
+		return true;
+	if (!!bc != fscrypt_inode_uses_inline_crypto(inode))
+		return false;
+	if (!bc)
+		return true;
+
+	/*
+	 * Comparing the key pointers is good enough, as all I/O for each key
+	 * uses the same pointer.  I.e., there's currently no need to support
+	 * merging requests where the keys are the same but the pointers differ.
+	 */
+	if (bc->bc_key != ei->prep_key.blk_key)
+		return false;
+
+	fscrypt_generate_dun(inode->i_crypt_info, next_lblk, next_dun);
+	return bio_crypt_dun_is_contiguous(bc, bio->bi_iter.bi_size, next_dun);
+}
+EXPORT_SYMBOL_GPL(fscrypt_mergeable_extent_bio);
+
 /**
  * fscrypt_mergeable_bio_bh() - test whether data can be added to a bio
  * @bio: the bio being built up
diff --git a/fs/crypto/keysetup.c b/fs/crypto/keysetup.c
index cbcbe582737e..55716ed03478 100644
--- a/fs/crypto/keysetup.c
+++ b/fs/crypto/keysetup.c
@@ -806,3 +806,155 @@ int fscrypt_drop_inode(struct inode *inode)
 	return !is_master_key_secret_present(&ci->ci_master_key->mk_secret);
 }
 EXPORT_SYMBOL_GPL(fscrypt_drop_inode);
+
+static struct fscrypt_extent_info *
+setup_extent_info(struct inode *inode, const u8 nonce[FSCRYPT_FILE_NONCE_SIZE])
+{
+	struct fscrypt_extent_info *ei;
+	struct fscrypt_inode_info *ci;
+	struct fscrypt_master_key *mk;
+	u8 derived_key[FSCRYPT_MAX_KEY_SIZE];
+	int err;
+
+	ci = inode->i_crypt_info;
+
+	ei = kmem_cache_zalloc(fscrypt_extent_info_cachep, GFP_KERNEL);
+	if (!ei)
+		return ERR_PTR(-ENOMEM);
+
+	refcount_set(&ei->refs, 1);
+	memcpy(ei->nonce, nonce, FSCRYPT_FILE_NONCE_SIZE);
+	ei->sb = inode->i_sb;
+
+	mk = ci->ci_master_key;
+	down_read(&mk->mk_sem);
+	if (!is_master_key_secret_present(&mk->mk_secret)) {
+		err = -ENOKEY;
+		goto out_free;
+	}
+
+	err = fscrypt_hkdf_expand(&mk->mk_secret.hkdf,
+				  HKDF_CONTEXT_PER_EXTENT_ENC_KEY, ei->nonce,
+				  FSCRYPT_FILE_NONCE_SIZE, derived_key,
+				  ci->ci_mode->keysize);
+	if (err)
+		goto out_free;
+
+	err = fscrypt_prepare_inline_crypt_key(&ei->prep_key, derived_key, ci);
+	memzero_explicit(derived_key, ci->ci_mode->keysize);
+	if (err)
+		goto out_free;
+	up_read(&mk->mk_sem);
+	return ei;
+out_free:
+	up_read(&mk->mk_sem);
+	memzero_explicit(ei, sizeof(*ei));
+	kmem_cache_free(fscrypt_extent_info_cachep, ei);
+	return ERR_PTR(err);
+}
+
+/**
+ * fscrypt_prepare_new_extent() - prepare to create a new extent for a file
+ * @inode: the possibly-encrypted inode
+ *
+ * If the inode is encrypted, setup the fscrypt_extent_info for a new extent.
+ * This will include the nonce and the derived key necessary for the extent to
+ * be encrypted.  This is only meant to be used with inline crypto.
+ *
+ * This doesn't persist the new extents encryption context, this is done later
+ * by calling fscrypt_set_extent_context().
+ *
+ * Return: The newly allocated fscrypt_extent_info on success, -EOPNOTSUPP if
+ *	   we're not encrypted, or another -errno code
+ */
+struct fscrypt_extent_info *fscrypt_prepare_new_extent(struct inode *inode)
+{
+	u8 nonce[FSCRYPT_FILE_NONCE_SIZE];
+
+	if (!fscrypt_inode_uses_inline_crypto(inode))
+		return ERR_PTR(-EOPNOTSUPP);
+
+	get_random_bytes(nonce, FSCRYPT_FILE_NONCE_SIZE);
+	return setup_extent_info(inode, nonce);
+}
+EXPORT_SYMBOL_GPL(fscrypt_prepare_new_extent);
+
+/**
+ * fscrypt_load_extent_info() - create an fscrypt_extent_info from the context
+ * @inode: the inode
+ * @ctx: the context buffer
+ * @ctx_size: the size of the context buffer
+ *
+ * Create the file_extent_info and derive the key based on the
+ * fscrypt_extent_context buffer that is probided.
+ *
+ * Return: The newly allocated fscrypt_extent_info on success, -EOPNOTSUPP if
+ *	   we're not encrypted, or another -errno code
+ */
+struct fscrypt_extent_info *fscrypt_load_extent_info(struct inode *inode,
+						     u8 *ctx, size_t ctx_size)
+{
+	struct fscrypt_extent_context extent_ctx;
+	const struct fscrypt_inode_info *ci = inode->i_crypt_info;
+	const struct fscrypt_policy_v2 *policy = &ci->ci_policy.v2;
+
+	if (!fscrypt_inode_uses_inline_crypto(inode))
+		return ERR_PTR(-EOPNOTSUPP);
+	if (ctx_size < sizeof(extent_ctx))
+		return ERR_PTR(-EINVAL);
+
+	memcpy(&extent_ctx, ctx, sizeof(extent_ctx));
+
+	/*
+	 * For now we need to validate that the master key for the inode matches
+	 * the extent.
+	 */
+	if (memcmp(extent_ctx.master_key_identifier,
+		   policy->master_key_identifier,
+		   sizeof(extent_ctx.master_key_identifier)))
+		return ERR_PTR(-EINVAL);
+
+	return setup_extent_info(inode, extent_ctx.nonce);
+}
+EXPORT_SYMBOL(fscrypt_load_extent_info);
+
+/**
+ * fscrypt_put_extent_info() - free the extent_info fscrypt data
+ * @ei: the extent_info being evicted
+ *
+ * Drop a reference and possibly free the fscrypt_extent_info.
+ *
+ * Note this will unload the key from the block layer, which takes the crypto
+ * profile semaphore to unload the key.  Make sure you're not dropping this in a
+ * context that can't sleep.
+ */
+void fscrypt_put_extent_info(struct fscrypt_extent_info *ei)
+{
+	if (!ei)
+		return;
+
+	if (!refcount_dec_and_test(&ei->refs))
+		return;
+
+	fscrypt_destroy_prepared_key(ei->sb, &ei->prep_key);
+	memzero_explicit(ei, sizeof(*ei));
+	kmem_cache_free(fscrypt_extent_info_cachep, ei);
+}
+EXPORT_SYMBOL_GPL(fscrypt_put_extent_info);
+
+/**
+ * fscrypt_get_extent_info() - get a ref on the fscrypt extent info
+ * @ei: the extent_info to get.
+ *
+ * Get a reference on the fscrypt_extent_info.
+ *
+ * Return: the ei with an extra ref, NULL if there was no ei passed in.
+ */
+struct fscrypt_extent_info *fscrypt_get_extent_info(struct fscrypt_extent_info *ei)
+{
+	if (!ei)
+		return NULL;
+	refcount_inc(&ei->refs);
+	return ei;
+}
+EXPORT_SYMBOL_GPL(fscrypt_get_extent_info);
diff --git a/fs/crypto/policy.c b/fs/crypto/policy.c
index aa94bfe6c172..8b8da04068b8 100644
--- a/fs/crypto/policy.c
+++ b/fs/crypto/policy.c
@@ -763,6 +763,53 @@ int fscrypt_set_context(struct inode *inode, void *fs_data)
 }
 EXPORT_SYMBOL_GPL(fscrypt_set_context);
 
+/**
+ * fscrypt_set_extent_context() - Set the fscrypt extent context of a new extent
+ * @inode: the inode this extent belongs to
+ * @ei: the fscrypt_extent_info for the given extent
+ * @buf: the buffer to copy the fscrypt extent context into
+ *
+ * This should be called after fscrypt_prepare_new_extent(), using the
+ * fscrypt_extent_info that was created at that point.
+ *
+ * Return: the size of the fscrypt_extent_context, errno if the inode has the
+ *	   wrong policy version.
+ */
+ssize_t fscrypt_set_extent_context(struct inode *inode,
+				   struct fscrypt_extent_info *ei, u8 *buf)
+{
+	struct fscrypt_extent_context *ctx = (struct fscrypt_extent_context *)buf;
+	const struct fscrypt_inode_info *ci = inode->i_crypt_info;
+
+	if (ci->ci_policy.version != 2)
+		return -EINVAL;
+
+	ctx->version = 1;
+	memcpy(ctx->master_key_identifier,
+	       ci->ci_policy.v2.master_key_identifier,
+	       sizeof(ctx->master_key_identifier));
+	memcpy(ctx->nonce, ei->nonce, FSCRYPT_FILE_NONCE_SIZE);
+	return sizeof(struct fscrypt_extent_context);
+}
+EXPORT_SYMBOL_GPL(fscrypt_set_extent_context);
+
+/**
+ * fscrypt_extent_context_size() - Return the size of the on-disk extent context
+ * @inode: the inode this extent belongs to.
+ *
+ * Return the size of the extent context for this inode.  Since there is only
+ * one extent context version currently this is just the size of the extent
+ * context if the inode is encrypted.
+ */
+size_t fscrypt_extent_context_size(struct inode *inode)
+{
+	if (!IS_ENCRYPTED(inode))
+		return 0;
+
+	return sizeof(struct fscrypt_extent_context);
+}
+EXPORT_SYMBOL_GPL(fscrypt_extent_context_size);
+
 /**
  * fscrypt_parse_test_dummy_encryption() - parse the test_dummy_encryption mount option
  * @param: the mount option
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index ece426ac1d73..266416742c72 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -32,6 +32,7 @@
 
 union fscrypt_policy;
 struct fscrypt_inode_info;
+struct fscrypt_extent_info;
 struct fs_parameter;
 struct seq_file;
 
@@ -66,6 +67,9 @@ struct fscrypt_name {
  */
 #define FS_CFLG_OWN_PAGES (1U << 1)
 
+/* If set, the file system is using extent based encryption. */
+#define FS_CFLG_EXTENT_ENCRYPTION (1U << 2)
+
 /* Crypto operations for filesystems */
 struct fscrypt_operations {
 
@@ -293,6 +297,11 @@ int fscrypt_ioctl_get_nonce(struct file *filp, void __user *arg);
 int fscrypt_has_permitted_context(struct inode *parent, struct inode *child);
 int fscrypt_context_for_new_inode(void *ctx, struct inode *inode);
 int fscrypt_set_context(struct inode *inode, void *fs_data);
+ssize_t fscrypt_set_extent_context(struct inode *inode,
+				   struct fscrypt_extent_info *ei, u8 *buf);
+struct fscrypt_extent_info *fscrypt_load_extent_info(struct inode *inode,
+						     u8 *ctx, size_t ctx_size);
+size_t fscrypt_extent_context_size(struct inode *inode);
 
 struct fscrypt_dummy_policy {
 	const union fscrypt_policy *policy;
@@ -329,6 +338,9 @@ int fscrypt_prepare_new_inode(struct inode *dir, struct inode *inode,
 void fscrypt_put_encryption_info(struct inode *inode);
 void fscrypt_free_inode(struct inode *inode);
 int fscrypt_drop_inode(struct inode *inode);
+struct fscrypt_extent_info *fscrypt_prepare_new_extent(struct inode *inode);
+void fscrypt_put_extent_info(struct fscrypt_extent_info *ei);
+struct fscrypt_extent_info *fscrypt_get_extent_info(struct fscrypt_extent_info *ei);
 
 /* fname.c */
 int fscrypt_fname_encrypt(const struct inode *inode, const struct qstr *iname,
@@ -539,6 +551,24 @@ fscrypt_free_dummy_policy(struct fscrypt_dummy_policy *dummy_policy)
 {
 }
 
+static inline ssize_t
+fscrypt_set_extent_context(struct inode *inode, struct fscrypt_extent_info *ei,
+			   u8 *buf)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline struct fscrypt_extent_info *
+fscrypt_load_extent_info(struct inode *inode, u8 *ctx, size_t ctx_size)
+{
+	return ERR_PTR(-EOPNOTSUPP);
+}
+
+static inline size_t fscrypt_extent_context_size(struct inode *inode)
+{
+	return 0;
+}
+
 /* keyring.c */
 static inline void fscrypt_destroy_keyring(struct super_block *sb)
 {
@@ -591,6 +621,20 @@ static inline int fscrypt_drop_inode(struct inode *inode)
 	return 0;
 }
 
+static inline struct fscrypt_extent_info *
+fscrypt_prepare_new_extent(struct inode *inode)
+{
+	return ERR_PTR(-EOPNOTSUPP);
+}
+
+static inline void fscrypt_put_extent_info(struct fscrypt_extent_info *ei) { }
+
+static inline struct fscrypt_extent_info *
+fscrypt_get_extent_info(struct fscrypt_extent_info *ei)
+{
+	return ei;
+}
+
  /* fname.c */
 static inline int fscrypt_setup_filename(struct inode *dir,
 					 const struct qstr *iname,
@@ -772,6 +816,11 @@ void fscrypt_set_bio_crypt_ctx(struct bio *bio,
 			       const struct inode *inode, u64 first_lblk,
 			       gfp_t gfp_mask);
 
+void fscrypt_set_bio_crypt_ctx_from_extent(struct bio *bio,
+					   const struct inode *inode,
+					   const struct fscrypt_extent_info *ei,
+					   u64 first_lblk, gfp_t gfp_mask);
+
 void fscrypt_set_bio_crypt_ctx_bh(struct bio *bio,
 				  const struct buffer_head *first_bh,
 				  gfp_t gfp_mask);
@@ -782,6 +831,10 @@ bool fscrypt_mergeable_bio(struct bio *bio, const struct inode *inode,
 bool fscrypt_mergeable_bio_bh(struct bio *bio,
 			      const struct buffer_head *next_bh);
 
+bool fscrypt_mergeable_extent_bio(struct bio *bio, const struct inode *inode,
+				  const struct fscrypt_extent_info *ei,
+				  u64 next_lblk);
+
 bool fscrypt_dio_supported(struct inode *inode);
 
 u64 fscrypt_limit_io_blocks(const struct inode *inode, u64 lblk, u64 nr_blocks);
@@ -797,6 +850,11 @@ static inline void fscrypt_set_bio_crypt_ctx(struct bio *bio,
 					     const struct inode *inode,
 					     u64 first_lblk, gfp_t gfp_mask) { }
 
+static inline void fscrypt_set_bio_crypt_ctx_from_extent(struct bio *bio,
+					const struct inode *inode,
+					const struct fscrypt_extent_info *ei,
+					u64 first_lblk, gfp_t gfp_mask) { }
+
 static inline void fscrypt_set_bio_crypt_ctx_bh(
 					 struct bio *bio,
 					 const struct buffer_head *first_bh,
@@ -809,6 +867,14 @@ static inline bool fscrypt_mergeable_bio(struct bio *bio,
 	return true;
 }
 
+static inline bool fscrypt_mergeable_extent_bio(struct bio *bio,
+						const struct inode *inode,
+						const struct fscrypt_extent_info *ei,
+						u64 next_lblk)
+{
+	return true;
+}
+
 static inline bool fscrypt_mergeable_bio_bh(struct bio *bio,
 					    const struct buffer_head *next_bh)
 {
-- 
2.41.0

[PATCH 03/35] fscrypt: disable all but standard v2 policies for extent encryption

[Josef Bacik]

The different encryption related options for fscrypt are too numerous to
support for extent based encryption.  Support for a few of these options
could possibly be added, but since they're niche options simply reject
them for file systems using extent based encryption.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/crypto/policy.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/fs/crypto/policy.c b/fs/crypto/policy.c
index 8b8da04068b8..38807d0ee742 100644
--- a/fs/crypto/policy.c
+++ b/fs/crypto/policy.c
@@ -198,6 +198,12 @@ static bool fscrypt_supported_v1_policy(const struct fscrypt_policy_v1 *policy,
 		return false;
 	}
 
+	if (inode->i_sb->s_cop->flags & FS_CFLG_EXTENT_ENCRYPTION) {
+		fscrypt_warn(inode,
+			     "v1 policies can't be used on file systems that use extent encryption");
+		return false;
+	}
+
 	return true;
 }
 
@@ -233,6 +239,12 @@ static bool fscrypt_supported_v2_policy(const struct fscrypt_policy_v2 *policy,
 		return false;
 	}
 
+	if ((inode->i_sb->s_cop->flags & FS_CFLG_EXTENT_ENCRYPTION) && count) {
+		fscrypt_warn(inode,
+			     "Encryption flags aren't supported on file systems that use extent encryption");
+		return false;
+	}
+
 	if ((policy->flags & FSCRYPT_POLICY_FLAG_DIRECT_KEY) &&
 	    !supported_direct_key_modes(inode, policy->contents_encryption_mode,
 					policy->filenames_encryption_mode))
-- 
2.41.0

[PATCH 04/35] blk-crypto: add a process bio callback

[Josef Bacik]

Btrfs does checksumming, and the checksums need to match the bytes on
disk.  In order to facilitate this add a process bio callback for the
blk-crypto layer.  This allows the file system to specify a callback and
then can process the encrypted bio as necessary.

For btrfs, writes will have the checksums calculated and saved into our
relevant data structures for storage once the write completes.  For
reads we will validate the checksums match what is on disk and error out
if there is a mismatch.

This is incompatible with native encryption obviously, so make sure we
don't use native encryption if this callback is set.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 block/blk-crypto-fallback.c        | 28 ++++++++++++++++++++++++++++
 block/blk-crypto-profile.c         |  2 ++
 block/blk-crypto.c                 |  6 +++++-
 fs/crypto/inline_crypt.c           |  3 ++-
 include/linux/blk-crypto-profile.h |  7 +++++++
 include/linux/blk-crypto.h         |  9 +++++++--
 include/linux/fscrypt.h            | 14 ++++++++++++++
 7 files changed, 65 insertions(+), 4 deletions(-)

diff --git a/block/blk-crypto-fallback.c b/block/blk-crypto-fallback.c
index e6468eab2681..8b4a83534127 100644
--- a/block/blk-crypto-fallback.c
+++ b/block/blk-crypto-fallback.c
@@ -346,6 +346,15 @@ static bool blk_crypto_fallback_encrypt_bio(struct bio **bio_ptr)
 		}
 	}
 
+	/* Process the encrypted bio before we submit it. */
+	if (bc->bc_key->crypto_cfg.process_bio) {
+		blk_st = bc->bc_key->crypto_cfg.process_bio(src_bio, enc_bio);
+		if (blk_st != BLK_STS_OK) {
+			src_bio->bi_status = blk_st;
+			goto out_free_bounce_pages;
+		}
+	}
+
 	enc_bio->bi_private = src_bio;
 	enc_bio->bi_end_io = blk_crypto_fallback_encrypt_endio;
 	*bio_ptr = enc_bio;
@@ -391,6 +400,24 @@ static void blk_crypto_fallback_decrypt_bio(struct work_struct *work)
 	unsigned int i;
 	blk_status_t blk_st;
 
+	/*
+	 * Process the bio first before trying to decrypt.
+	 *
+	 * NOTE: btrfs expects that this bio is the same that was submitted.  If
+	 * at any point this changes we will need to update process_bio to take
+	 * f_ctx->crypt_iter in order to make sure we can iterate the pages for
+	 * checksumming.  We're currently saving this in our btrfs_bio, so this
+	 * works, but if at any point in the future we start allocating a bounce
+	 * bio or something we need to update this callback.
+	 */
+	if (bc->bc_key->crypto_cfg.process_bio) {
+		blk_st = bc->bc_key->crypto_cfg.process_bio(bio, bio);
+		if (blk_st != BLK_STS_OK) {
+			bio->bi_status = blk_st;
+			goto out_no_keyslot;
+		}
+	}
+
 	/*
 	 * Get a blk-crypto-fallback keyslot that contains a crypto_skcipher for
 	 * this bio's algorithm and key.
@@ -560,6 +587,7 @@ static int blk_crypto_fallback_init(void)
 
 	blk_crypto_fallback_profile->ll_ops = blk_crypto_fallback_ll_ops;
 	blk_crypto_fallback_profile->max_dun_bytes_supported = BLK_CRYPTO_MAX_IV_SIZE;
+	blk_crypto_fallback_profile->process_bio_supported = true;
 
 	/* All blk-crypto modes have a crypto API fallback. */
 	for (i = 0; i < BLK_ENCRYPTION_MODE_MAX; i++)
diff --git a/block/blk-crypto-profile.c b/block/blk-crypto-profile.c
index 7fabc883e39f..640cf2ea3fcc 100644
--- a/block/blk-crypto-profile.c
+++ b/block/blk-crypto-profile.c
@@ -352,6 +352,8 @@ bool __blk_crypto_cfg_supported(struct blk_crypto_profile *profile,
 		return false;
 	if (profile->max_dun_bytes_supported < cfg->dun_bytes)
 		return false;
+	if (cfg->process_bio && !profile->process_bio_supported)
+		return false;
 	return true;
 }
 
diff --git a/block/blk-crypto.c b/block/blk-crypto.c
index 4d760b092deb..50556952df19 100644
--- a/block/blk-crypto.c
+++ b/block/blk-crypto.c
@@ -321,6 +321,8 @@ int __blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio,
  * @dun_bytes: number of bytes that will be used to specify the DUN when this
  *	       key is used
  * @data_unit_size: the data unit size to use for en/decryption
+ * @process_bio: the call back if the upper layer needs to process the encrypted
+ *		 bio
  *
  * Return: 0 on success, -errno on failure.  The caller is responsible for
  *	   zeroizing both blk_key and raw_key when done with them.
@@ -328,7 +330,8 @@ int __blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio,
 int blk_crypto_init_key(struct blk_crypto_key *blk_key, const u8 *raw_key,
 			enum blk_crypto_mode_num crypto_mode,
 			unsigned int dun_bytes,
-			unsigned int data_unit_size)
+			unsigned int data_unit_size,
+			blk_crypto_process_bio_t process_bio)
 {
 	const struct blk_crypto_mode *mode;
 
@@ -350,6 +353,7 @@ int blk_crypto_init_key(struct blk_crypto_key *blk_key, const u8 *raw_key,
 	blk_key->crypto_cfg.crypto_mode = crypto_mode;
 	blk_key->crypto_cfg.dun_bytes = dun_bytes;
 	blk_key->crypto_cfg.data_unit_size = data_unit_size;
+	blk_key->crypto_cfg.process_bio = process_bio;
 	blk_key->data_unit_size_bits = ilog2(data_unit_size);
 	blk_key->size = mode->keysize;
 	memcpy(blk_key->raw, raw_key, mode->keysize);
diff --git a/fs/crypto/inline_crypt.c b/fs/crypto/inline_crypt.c
index 21e1851d4ba7..a66a555d84ee 100644
--- a/fs/crypto/inline_crypt.c
+++ b/fs/crypto/inline_crypt.c
@@ -168,7 +168,8 @@ int fscrypt_prepare_inline_crypt_key(struct fscrypt_prepared_key *prep_key,
 		return -ENOMEM;
 
 	err = blk_crypto_init_key(blk_key, raw_key, crypto_mode,
-				  fscrypt_get_dun_bytes(ci), sb->s_blocksize);
+				  fscrypt_get_dun_bytes(ci), sb->s_blocksize,
+				  sb->s_cop->process_bio);
 	if (err) {
 		fscrypt_err(inode, "error %d initializing blk-crypto key", err);
 		goto fail;
diff --git a/include/linux/blk-crypto-profile.h b/include/linux/blk-crypto-profile.h
index 90ab33cb5d0e..3c002e85631a 100644
--- a/include/linux/blk-crypto-profile.h
+++ b/include/linux/blk-crypto-profile.h
@@ -100,6 +100,13 @@ struct blk_crypto_profile {
 	 */
 	struct device *dev;
 
+	/**
+	 * @process_bio_supported: Some things, like btrfs, require the
+	 * encrypted data for checksumming. Drivers set this to true if they can
+	 * handle the process_bio() callback.
+	 */
+	bool process_bio_supported;
+
 	/* private: The following fields shouldn't be accessed by drivers. */
 
 	/* Number of keyslots, or 0 if not applicable */
diff --git a/include/linux/blk-crypto.h b/include/linux/blk-crypto.h
index 5e5822c18ee4..194c1d727013 100644
--- a/include/linux/blk-crypto.h
+++ b/include/linux/blk-crypto.h
@@ -6,7 +6,7 @@
 #ifndef __LINUX_BLK_CRYPTO_H
 #define __LINUX_BLK_CRYPTO_H
 
-#include <linux/types.h>
+#include <linux/blk_types.h>
 
 enum blk_crypto_mode_num {
 	BLK_ENCRYPTION_MODE_INVALID,
@@ -17,6 +17,9 @@ enum blk_crypto_mode_num {
 	BLK_ENCRYPTION_MODE_MAX,
 };
 
+typedef blk_status_t (blk_crypto_process_bio_t)(struct bio *orig_bio,
+						struct bio *enc_bio);
+
 #define BLK_CRYPTO_MAX_KEY_SIZE		64
 /**
  * struct blk_crypto_config - an inline encryption key's crypto configuration
@@ -31,6 +34,7 @@ struct blk_crypto_config {
 	enum blk_crypto_mode_num crypto_mode;
 	unsigned int data_unit_size;
 	unsigned int dun_bytes;
+	blk_crypto_process_bio_t *process_bio;
 };
 
 /**
@@ -90,7 +94,8 @@ bool bio_crypt_dun_is_contiguous(const struct bio_crypt_ctx *bc,
 int blk_crypto_init_key(struct blk_crypto_key *blk_key, const u8 *raw_key,
 			enum blk_crypto_mode_num crypto_mode,
 			unsigned int dun_bytes,
-			unsigned int data_unit_size);
+			unsigned int data_unit_size,
+			blk_crypto_process_bio_t process_bio);
 
 int blk_crypto_start_using_key(struct block_device *bdev,
 			       const struct blk_crypto_key *key);
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 266416742c72..07493ad2588b 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -16,6 +16,7 @@
 #include <linux/fs.h>
 #include <linux/mm.h>
 #include <linux/slab.h>
+#include <linux/blk-crypto.h>
 #include <uapi/linux/fscrypt.h>
 
 /*
@@ -180,6 +181,19 @@ struct fscrypt_operations {
 	 */
 	struct block_device **(*get_devices)(struct super_block *sb,
 					     unsigned int *num_devs);
+
+	/*
+	 * A callback if the file system requires the ability to process the
+	 * encrypted bio.
+	 *
+	 * @orig_bio: the original bio submitted.
+	 * @enc_bio: the encrypted bio.
+	 *
+	 * For writes the enc_bio will be different from the orig_bio, for reads
+	 * they will be the same.  For reads we get the bio before it is
+	 * decrypted, for writes we get the bio before it is submitted.
+	 */
+	blk_crypto_process_bio_t *process_bio;
 };
 
 static inline struct fscrypt_inode_info *fscrypt_get_info(const struct inode *inode)
-- 
2.41.0

[PATCH 05/35] fscrypt: expose fscrypt_nokey_name

[Josef Bacik]

From: Omar Sandoval <osandov@osandov.com>

btrfs stores its data structures, including filenames in directories, in
its own buffer implementation, struct extent_buffer, composed of
several non-contiguous pages. We could copy filenames into a
temporary buffer and use fscrypt_match_name() against that buffer, such
extensive memcpying would be expensive. Instead, exposing
fscrypt_nokey_name as in this change allows btrfs to recapitulate
fscrypt_match_name() using methods on struct extent_buffer instead of
dealing with a raw byte array.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/crypto/fname.c       | 39 +--------------------------------------
 include/linux/fscrypt.h | 37 +++++++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+), 38 deletions(-)

diff --git a/fs/crypto/fname.c b/fs/crypto/fname.c
index 7b3fc189593a..5607ee52703e 100644
--- a/fs/crypto/fname.c
+++ b/fs/crypto/fname.c
@@ -14,7 +14,6 @@
 #include <linux/namei.h>
 #include <linux/scatterlist.h>
 #include <crypto/hash.h>
-#include <crypto/sha2.h>
 #include <crypto/skcipher.h>
 #include "fscrypt_private.h"
 
@@ -26,43 +25,7 @@
 #define FSCRYPT_FNAME_MIN_MSG_LEN 16
 
 /*
- * struct fscrypt_nokey_name - identifier for directory entry when key is absent
- *
- * When userspace lists an encrypted directory without access to the key, the
- * filesystem must present a unique "no-key name" for each filename that allows
- * it to find the directory entry again if requested.  Naively, that would just
- * mean using the ciphertext filenames.  However, since the ciphertext filenames
- * can contain illegal characters ('\0' and '/'), they must be encoded in some
- * way.  We use base64url.  But that can cause names to exceed NAME_MAX (255
- * bytes), so we also need to use a strong hash to abbreviate long names.
- *
- * The filesystem may also need another kind of hash, the "dirhash", to quickly
- * find the directory entry.  Since filesystems normally compute the dirhash
- * over the on-disk filename (i.e. the ciphertext), it's not computable from
- * no-key names that abbreviate the ciphertext using the strong hash to fit in
- * NAME_MAX.  It's also not computable if it's a keyed hash taken over the
- * plaintext (but it may still be available in the on-disk directory entry);
- * casefolded directories use this type of dirhash.  At least in these cases,
- * each no-key name must include the name's dirhash too.
- *
- * To meet all these requirements, we base64url-encode the following
- * variable-length structure.  It contains the dirhash, or 0's if the filesystem
- * didn't provide one; up to 149 bytes of the ciphertext name; and for
- * ciphertexts longer than 149 bytes, also the SHA-256 of the remaining bytes.
- *
- * This ensures that each no-key name contains everything needed to find the
- * directory entry again, contains only legal characters, doesn't exceed
- * NAME_MAX, is unambiguous unless there's a SHA-256 collision, and that we only
- * take the performance hit of SHA-256 on very long filenames (which are rare).
- */
-struct fscrypt_nokey_name {
-	u32 dirhash[2];
-	u8 bytes[149];
-	u8 sha256[SHA256_DIGEST_SIZE];
-}; /* 189 bytes => 252 bytes base64url-encoded, which is <= NAME_MAX (255) */
-
-/*
- * Decoded size of max-size no-key name, i.e. a name that was abbreviated using
+ * Decoded size of max-size nokey name, i.e. a name that was abbreviated using
  * the strong hash and thus includes the 'sha256' field.  This isn't simply
  * sizeof(struct fscrypt_nokey_name), as the padding at the end isn't included.
  */
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 07493ad2588b..44dc10837499 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -17,6 +17,7 @@
 #include <linux/mm.h>
 #include <linux/slab.h>
 #include <linux/blk-crypto.h>
+#include <crypto/sha2.h>
 #include <uapi/linux/fscrypt.h>
 
 /*
@@ -56,6 +57,42 @@ struct fscrypt_name {
 #define fname_name(p)		((p)->disk_name.name)
 #define fname_len(p)		((p)->disk_name.len)
 
+/*
+ * struct fscrypt_nokey_name - identifier for directory entry when key is absent
+ *
+ * When userspace lists an encrypted directory without access to the key, the
+ * filesystem must present a unique "no-key name" for each filename that allows
+ * it to find the directory entry again if requested.  Naively, that would just
+ * mean using the ciphertext filenames.  However, since the ciphertext filenames
+ * can contain illegal characters ('\0' and '/'), they must be encoded in some
+ * way.  We use base64url.  But that can cause names to exceed NAME_MAX (255
+ * bytes), so we also need to use a strong hash to abbreviate long names.
+ *
+ * The filesystem may also need another kind of hash, the "dirhash", to quickly
+ * find the directory entry.  Since filesystems normally compute the dirhash
+ * over the on-disk filename (i.e. the ciphertext), it's not computable from
+ * no-key names that abbreviate the ciphertext using the strong hash to fit in
+ * NAME_MAX.  It's also not computable if it's a keyed hash taken over the
+ * plaintext (but it may still be available in the on-disk directory entry);
+ * casefolded directories use this type of dirhash.  At least in these cases,
+ * each no-key name must include the name's dirhash too.
+ *
+ * To meet all these requirements, we base64url-encode the following
+ * variable-length structure.  It contains the dirhash, or 0's if the filesystem
+ * didn't provide one; up to 149 bytes of the ciphertext name; and for
+ * ciphertexts longer than 149 bytes, also the SHA-256 of the remaining bytes.
+ *
+ * This ensures that each no-key name contains everything needed to find the
+ * directory entry again, contains only legal characters, doesn't exceed
+ * NAME_MAX, is unambiguous unless there's a SHA-256 collision, and that we only
+ * take the performance hit of SHA-256 on very long filenames (which are rare).
+ */
+struct fscrypt_nokey_name {
+	u32 dirhash[2];
+	u8 bytes[149];
+	u8 sha256[SHA256_DIGEST_SIZE];
+}; /* 189 bytes => 252 bytes base64url-encoded, which is <= NAME_MAX (255) */
+
 /* Maximum value for the third parameter of fscrypt_operations.set_context(). */
 #define FSCRYPT_SET_CONTEXT_MAX_SIZE	40
 
-- 
2.41.0

[PATCH 06/35] fscrypt: add documentation about extent encryption

[Josef Bacik]

Add a couple of sections to the fscrypt documentation about per-extent
encryption.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 Documentation/filesystems/fscrypt.rst | 36 +++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/Documentation/filesystems/fscrypt.rst b/Documentation/filesystems/fscrypt.rst
index a624e92f2687..9981eaf61f32 100644
--- a/Documentation/filesystems/fscrypt.rst
+++ b/Documentation/filesystems/fscrypt.rst
@@ -256,6 +256,21 @@ alternative master keys or to support rotating master keys.  Instead,
 the master keys may be wrapped in userspace, e.g. as is done by the
 `fscrypt <https://github.com/google/fscrypt>`_ tool.
 
+Per-extent encryption keys
+--------------------------
+
+For certain file systems, such as btrfs, it's desired to derive a
+per-extent encryption key.  This is to enable features such as snapshots
+and reflink, where you could have different inodes pointing at the same
+extent.  When a new extent is created fscrypt randomly generates a
+16-byte nonce and the file system stores it along side the extent.
+Then, it uses a KDF (as described in `Key derivation function`_) to
+derive the extent's key from the master key and nonce.
+
+Currently the inode's master key and encryption policy must match the
+extent, so you cannot share extents between inodes that were encrypted
+differently.
+
 DIRECT_KEY policies
 -------------------
 
@@ -1339,6 +1354,27 @@ by the kernel and is used as KDF input or as a tweak to cause
 different files to be encrypted differently; see `Per-file encryption
 keys`_ and `DIRECT_KEY policies`_.
 
+Extent encryption context
+-------------------------
+
+The extent encryption context mirrors the important parts of the above
+`Encryption context`_, with a few ommisions.  The struct is defined as
+follows::
+
+        struct fscrypt_extent_context {
+                u8 version;
+                u8 encryption_mode;
+                u8 master_key_identifier[FSCRYPT_KEY_IDENTIFIER_SIZE];
+                u8 nonce[FSCRYPT_FILE_NONCE_SIZE];
+        };
+
+Currently all fields much match the containing inode's encryption
+context, with the exception of the nonce.
+
+Additionally extent encryption is only supported with
+FSCRYPT_EXTENT_CONTEXT_V2 using the standard policy, all other policies
+are disallowed.
+
 Data path changes
 -----------------
 
-- 
2.41.0

[PATCH 07/35] btrfs: add infrastructure for safe em freeing

[Josef Bacik]

When we add fscrypt support we're going to have fscrypt objects hanging
off of extent_maps.  This includes a block key, which if we're the last
one freeing the key we may have to unregister it from the block layer.
This requires taking a semaphore in the block layer, which means we
can't free em's under the extent map tree lock.

Thankfully we only do this in two places, one where we're dropping a
range of extent maps, and when we're freeing logged extents.  Add a
free_extent_map_safe() which will add the em to a list in the em_tree if
we free'd the object.  Currently this is unconditional but will be
changed to conditional on the fscrypt object we will add in a later
patch.

To process these delayed objects add a free_pending_extent_maps() that
is called after the lock has been dropped on the em_tree.  This will
process the extent maps on the freed list and do the appropriate freeing
work in a safe manner.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/extent_map.c | 80 ++++++++++++++++++++++++++++++++++++++++---
 fs/btrfs/extent_map.h | 10 ++++++
 fs/btrfs/tree-log.c   |  6 ++--
 3 files changed, 89 insertions(+), 7 deletions(-)

diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index a6d8368ed0ed..af5ff6b10865 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -35,7 +35,9 @@ void __cold extent_map_exit(void)
 void extent_map_tree_init(struct extent_map_tree *tree)
 {
 	tree->map = RB_ROOT_CACHED;
+	tree->flags = 0;
 	INIT_LIST_HEAD(&tree->modified_extents);
+	INIT_LIST_HEAD(&tree->freed_extents);
 	rwlock_init(&tree->lock);
 }
 
@@ -53,9 +55,17 @@ struct extent_map *alloc_extent_map(void)
 	em->compress_type = BTRFS_COMPRESS_NONE;
 	refcount_set(&em->refs, 1);
 	INIT_LIST_HEAD(&em->list);
+	INIT_LIST_HEAD(&em->free_list);
 	return em;
 }
 
+static void __free_extent_map(struct extent_map *em)
+{
+	if (test_bit(EXTENT_FLAG_FS_MAPPING, &em->flags))
+		kfree(em->map_lookup);
+	kmem_cache_free(extent_map_cache, em);
+}
+
 /*
  * Drop the reference out on @em by one and free the structure if the reference
  * count hits zero.
@@ -67,12 +77,69 @@ void free_extent_map(struct extent_map *em)
 	if (refcount_dec_and_test(&em->refs)) {
 		WARN_ON(extent_map_in_tree(em));
 		WARN_ON(!list_empty(&em->list));
-		if (test_bit(EXTENT_FLAG_FS_MAPPING, &em->flags))
-			kfree(em->map_lookup);
-		kmem_cache_free(extent_map_cache, em);
+		__free_extent_map(em);
 	}
 }
 
+/*
+ * Drop a ref for the extent map in the given tree.
+ *
+ * @tree:	tree that the em is a part of.
+ * @em:		the em to drop the reference to.
+ *
+ * Drop the reference count on @em by one, if the reference count hits 0 and
+ * there is an object on the em that can't be safely freed in the current
+ * context (if we are holding the extent_map_tree->lock for example), then add
+ * it to the freed_extents list on the extent_map_tree for later processing.
+ *
+ * This must be followed by a free_pending_extent_maps() to clear the pending
+ * frees.
+ */
+void free_extent_map_safe(struct extent_map_tree *tree,
+			  struct extent_map *em)
+{
+	lockdep_assert_held_write(&tree->lock);
+
+	if (!em)
+		return;
+
+	if (refcount_dec_and_test(&em->refs)) {
+		WARN_ON(extent_map_in_tree(em));
+		WARN_ON(!list_empty(&em->list));
+		list_add_tail(&em->free_list, &tree->freed_extents);
+		set_bit(EXTENT_MAP_TREE_PENDING_FREES, &tree->flags);
+	}
+}
+
+/*
+ * Free the em objects that exist on the em tree
+ *
+ * @tree:	the tree to free the objects from.
+ *
+ * If there are any objects on the em->freed_extents list go ahead and free them
+ * here in a safe way.  This is to be coupled with any uses of
+ * free_extent_map_safe().
+ */
+void free_pending_extent_maps(struct extent_map_tree *tree)
+{
+	struct extent_map *em;
+
+	/* Avoid taking the write lock if we don't have any pending frees. */
+	if (!test_and_clear_bit(EXTENT_MAP_TREE_PENDING_FREES, &tree->flags))
+		return;
+
+	write_lock(&tree->lock);
+	while ((em = list_first_entry_or_null(&tree->freed_extents,
+					      struct extent_map, free_list))) {
+		list_del_init(&em->free_list);
+		write_unlock(&tree->lock);
+		__free_extent_map(em);
+		cond_resched();
+		write_lock(&tree->lock);
+	}
+	write_unlock(&tree->lock);
+}
+
 /* Do the math around the end of an extent, handling wrapping. */
 static u64 range_end(u64 start, u64 len)
 {
@@ -684,10 +751,12 @@ static void drop_all_extent_maps_fast(struct extent_map_tree *tree)
 		clear_bit(EXTENT_FLAG_PINNED, &em->flags);
 		clear_bit(EXTENT_FLAG_LOGGING, &em->flags);
 		remove_extent_mapping(tree, em);
-		free_extent_map(em);
+		free_extent_map_safe(tree, em);
 		cond_resched_rwlock_write(&tree->lock);
 	}
 	write_unlock(&tree->lock);
+
+	free_pending_extent_maps(tree);
 }
 
 /*
@@ -908,13 +977,14 @@ void btrfs_drop_extent_map_range(struct btrfs_inode *inode, u64 start, u64 end,
 		free_extent_map(em);
 next:
 		/* Once for us (for our lookup reference). */
-		free_extent_map(em);
+		free_extent_map_safe(em_tree, em);
 
 		em = next_em;
 	}
 
 	write_unlock(&em_tree->lock);
 
+	free_pending_extent_maps(em_tree);
 	free_extent_map(split);
 	free_extent_map(split2);
 }
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index 35d27c756e08..2093720271ea 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -55,11 +55,18 @@ struct extent_map {
 	refcount_t refs;
 	unsigned int compress_type;
 	struct list_head list;
+	struct list_head free_list;
+};
+
+enum extent_map_flags {
+	EXTENT_MAP_TREE_PENDING_FREES,
 };
 
 struct extent_map_tree {
 	struct rb_root_cached map;
+	unsigned long flags;
 	struct list_head modified_extents;
+	struct list_head freed_extents;
 	rwlock_t lock;
 };
 
@@ -95,6 +102,9 @@ int split_extent_map(struct btrfs_inode *inode, u64 start, u64 len, u64 pre,
 
 struct extent_map *alloc_extent_map(void);
 void free_extent_map(struct extent_map *em);
+void free_extent_map_safe(struct extent_map_tree *tree,
+			  struct extent_map *em);
+void free_pending_extent_maps(struct extent_map_tree *tree);
 int __init extent_map_init(void);
 void __cold extent_map_exit(void);
 int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len, u64 gen);
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 6b98e0dbc0a4..c4d8900f91bb 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -4886,7 +4886,7 @@ static int btrfs_log_changed_extents(struct btrfs_trans_handle *trans,
 		 */
 		if (ret) {
 			clear_em_logging(tree, em);
-			free_extent_map(em);
+			free_extent_map_safe(tree, em);
 			continue;
 		}
 
@@ -4895,11 +4895,13 @@ static int btrfs_log_changed_extents(struct btrfs_trans_handle *trans,
 		ret = log_one_extent(trans, inode, em, path, ctx);
 		write_lock(&tree->lock);
 		clear_em_logging(tree, em);
-		free_extent_map(em);
+		free_extent_map_safe(tree, em);
 	}
 	WARN_ON(!list_empty(&extents));
 	write_unlock(&tree->lock);
 
+	free_pending_extent_maps(tree);
+
 	if (!ret)
 		ret = btrfs_log_prealloc_extents(trans, inode, path);
 	if (ret)
-- 
2.41.0

[PATCH 08/35] btrfs: disable various operations on encrypted inodes

[Josef Bacik]

From: Omar Sandoval <osandov@osandov.com>

Initially, only normal data extents will be encrypted. This change
forbids various other bits:
- allows reflinking only if both inodes have the same encryption status
- disable inline data on encrypted inodes

Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/inode.c   | 3 ++-
 fs/btrfs/reflink.c | 7 +++++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 52576deda654..6cba648d5656 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -630,7 +630,8 @@ static noinline int cow_file_range_inline(struct btrfs_inode *inode, u64 size,
 	 * compressed) data fits in a leaf and the configured maximum inline
 	 * size.
 	 */
-	if (size < i_size_read(&inode->vfs_inode) ||
+	if (IS_ENCRYPTED(&inode->vfs_inode) ||
+	    size < i_size_read(&inode->vfs_inode) ||
 	    size > fs_info->sectorsize ||
 	    data_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info) ||
 	    data_len > fs_info->max_inline)
diff --git a/fs/btrfs/reflink.c b/fs/btrfs/reflink.c
index fabd856e5079..3c66630d87ee 100644
--- a/fs/btrfs/reflink.c
+++ b/fs/btrfs/reflink.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 
 #include <linux/blkdev.h>
+#include <linux/fscrypt.h>
 #include <linux/iversion.h>
 #include "ctree.h"
 #include "fs.h"
@@ -809,6 +810,12 @@ static int btrfs_remap_file_range_prep(struct file *file_in, loff_t pos_in,
 		ASSERT(inode_in->i_sb == inode_out->i_sb);
 	}
 
+	/*
+	 * Can only reflink encrypted files if both files are encrypted.
+	 */
+	if (IS_ENCRYPTED(inode_in) != IS_ENCRYPTED(inode_out))
+		return -EINVAL;
+
 	/* Don't make the dst file partly checksummed */
 	if ((BTRFS_I(inode_in)->flags & BTRFS_INODE_NODATASUM) !=
 	    (BTRFS_I(inode_out)->flags & BTRFS_INODE_NODATASUM)) {
-- 
2.41.0

[PATCH 09/35] btrfs: disable verity on encrypted inodes

[Josef Bacik]

From: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>

Right now there isn't a way to encrypt things that aren't either
filenames in directories or data on blocks on disk with extent
encryption, so for now, disable verity usage with encryption on btrfs.

Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/verity.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/btrfs/verity.c b/fs/btrfs/verity.c
index 66e2270b0dae..92536913df04 100644
--- a/fs/btrfs/verity.c
+++ b/fs/btrfs/verity.c
@@ -588,6 +588,9 @@ static int btrfs_begin_enable_verity(struct file *filp)
 
 	ASSERT(inode_is_locked(file_inode(filp)));
 
+	if (IS_ENCRYPTED(&inode->vfs_inode))
+		return -EINVAL;
+
 	if (test_bit(BTRFS_INODE_VERITY_IN_PROGRESS, &inode->runtime_flags))
 		return -EBUSY;
 
-- 
2.41.0

[PATCH 10/35] btrfs: start using fscrypt hooks

[Josef Bacik]

From: Omar Sandoval <osandov@osandov.com>

In order to appropriately encrypt, create, open, rename, and various
symlink operations must call fscrypt hooks. These determine whether the
inode should be encrypted and do other preparatory actions. The
superblock must have fscrypt operations registered, so implement the
minimal set also, and introduce the new fscrypt.[ch] files to hold the
fscrypt-specific functionality. Also add the key prefix for fscrypt v1
keys.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/Makefile      |   1 +
 fs/btrfs/btrfs_inode.h |   1 +
 fs/btrfs/file.c        |   3 ++
 fs/btrfs/fscrypt.c     |   8 +++
 fs/btrfs/fscrypt.h     |  10 ++++
 fs/btrfs/inode.c       | 110 ++++++++++++++++++++++++++++++++++-------
 fs/btrfs/super.c       |   2 +
 7 files changed, 117 insertions(+), 18 deletions(-)
 create mode 100644 fs/btrfs/fscrypt.c
 create mode 100644 fs/btrfs/fscrypt.h

diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
index 525af975f61c..6e51d054c17a 100644
--- a/fs/btrfs/Makefile
+++ b/fs/btrfs/Makefile
@@ -39,6 +39,7 @@ btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o
 btrfs-$(CONFIG_BTRFS_FS_REF_VERIFY) += ref-verify.o
 btrfs-$(CONFIG_BLK_DEV_ZONED) += zoned.o
 btrfs-$(CONFIG_FS_VERITY) += verity.o
+btrfs-$(CONFIG_FS_ENCRYPTION) += fscrypt.o
 
 btrfs-$(CONFIG_BTRFS_FS_RUN_SANITY_TESTS) += tests/free-space-tests.o \
 	tests/extent-buffer-tests.o tests/btrfs-tests.o \
diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
index f2c928345d53..68ebb6096822 100644
--- a/fs/btrfs/btrfs_inode.h
+++ b/fs/btrfs/btrfs_inode.h
@@ -449,6 +449,7 @@ struct btrfs_new_inode_args {
 	struct posix_acl *default_acl;
 	struct posix_acl *acl;
 	struct fscrypt_name fname;
+	bool encrypt;
 };
 
 int btrfs_new_inode_prepare(struct btrfs_new_inode_args *args,
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 004c53482f05..8dcc5ae9c9e1 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -3710,6 +3710,9 @@ static int btrfs_file_open(struct inode *inode, struct file *filp)
 
 	filp->f_mode |= FMODE_NOWAIT | FMODE_BUF_RASYNC | FMODE_BUF_WASYNC |
 		        FMODE_CAN_ODIRECT;
+	ret = fscrypt_file_open(inode, filp);
+	if (ret)
+		return ret;
 
 	ret = fsverity_file_open(inode, filp);
 	if (ret)
diff --git a/fs/btrfs/fscrypt.c b/fs/btrfs/fscrypt.c
new file mode 100644
index 000000000000..3a53dc59c1e4
--- /dev/null
+++ b/fs/btrfs/fscrypt.c
@@ -0,0 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include "ctree.h"
+#include "fscrypt.h"
+
+const struct fscrypt_operations btrfs_fscrypt_ops = {
+	.key_prefix = "btrfs:"
+};
diff --git a/fs/btrfs/fscrypt.h b/fs/btrfs/fscrypt.h
new file mode 100644
index 000000000000..7f4e6888bd43
--- /dev/null
+++ b/fs/btrfs/fscrypt.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef BTRFS_FSCRYPT_H
+#define BTRFS_FSCRYPT_H
+
+#include <linux/fscrypt.h>
+
+extern const struct fscrypt_operations btrfs_fscrypt_ops;
+
+#endif /* BTRFS_FSCRYPT_H */
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 6cba648d5656..94c2e13934aa 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -5054,6 +5054,10 @@ static int btrfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
 	if (err)
 		return err;
 
+	err = fscrypt_prepare_setattr(dentry, attr);
+	if (err)
+		return err;
+
 	if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
 		err = btrfs_setsize(inode, attr);
 		if (err)
@@ -5208,11 +5212,8 @@ void btrfs_evict_inode(struct inode *inode)
 
 	trace_btrfs_inode_evict(inode);
 
-	if (!root) {
-		fsverity_cleanup_inode(inode);
-		clear_inode(inode);
-		return;
-	}
+	if (!root)
+		goto cleanup;
 
 	evict_inode_truncate_pages(inode);
 
@@ -5312,6 +5313,9 @@ void btrfs_evict_inode(struct inode *inode)
 	 * to retry these periodically in the future.
 	 */
 	btrfs_remove_delayed_node(BTRFS_I(inode));
+
+cleanup:
+	fscrypt_put_encryption_info(inode);
 	fsverity_cleanup_inode(inode);
 	clear_inode(inode);
 }
@@ -6097,6 +6101,12 @@ int btrfs_new_inode_prepare(struct btrfs_new_inode_args *args,
 		return ret;
 	}
 
+	ret = fscrypt_prepare_new_inode(dir, inode, &args->encrypt);
+	if (ret) {
+		fscrypt_free_filename(&args->fname);
+		return ret;
+	}
+
 	/* 1 to add inode item */
 	*trans_num_items = 1;
 	/* 1 to add compression property */
@@ -6570,9 +6580,13 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
 	if (inode->i_nlink >= BTRFS_LINK_MAX)
 		return -EMLINK;
 
+	err = fscrypt_prepare_link(old_dentry, dir, dentry);
+	if (err)
+		return err;
+
 	err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &fname);
 	if (err)
-		goto fail;
+		return err;
 
 	err = btrfs_set_inode_index(BTRFS_I(dir), &index);
 	if (err)
@@ -8519,6 +8533,7 @@ void btrfs_test_destroy_inode(struct inode *inode)
 
 void btrfs_free_inode(struct inode *inode)
 {
+	fscrypt_free_inode(inode);
 	kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
 }
 
@@ -8589,8 +8604,7 @@ int btrfs_drop_inode(struct inode *inode)
 	/* the snap/subvol tree is on deleting */
 	if (btrfs_root_refs(&root->root_item) == 0)
 		return 1;
-	else
-		return generic_drop_inode(inode);
+	return generic_drop_inode(inode) || fscrypt_drop_inode(inode);
 }
 
 static void init_once(void *foo)
@@ -9170,6 +9184,11 @@ static int btrfs_rename2(struct mnt_idmap *idmap, struct inode *old_dir,
 	if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
 		return -EINVAL;
 
+	ret = fscrypt_prepare_rename(old_dir, old_dentry, new_dir, new_dentry,
+				     flags);
+	if (ret)
+		return ret;
+
 	if (flags & RENAME_EXCHANGE)
 		ret = btrfs_rename_exchange(old_dir, old_dentry, new_dir,
 					    new_dentry);
@@ -9384,15 +9403,31 @@ static int btrfs_symlink(struct mnt_idmap *idmap, struct inode *dir,
 	};
 	unsigned int trans_num_items;
 	int err;
-	int name_len;
 	int datasize;
 	unsigned long ptr;
 	struct btrfs_file_extent_item *ei;
 	struct extent_buffer *leaf;
+	struct fscrypt_str disk_link;
+	size_t max_len;
+	u32 name_len = strlen(symname);
 
-	name_len = strlen(symname);
-	if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info))
-		return -ENAMETOOLONG;
+	/*
+	 * BTRFS_MAX_INLINE_DATA_SIZE() isn't actually telling the truth, we
+	 * actually limit inline data extents to
+	 * min(BTRFS_MAX_INLINE_DATA_SIZE(), sectorsize), so adjust max_len
+	 * given this wonderful bit of inconsistency.
+	 */
+	max_len = min_t(size_t, BTRFS_MAX_INLINE_DATA_SIZE(fs_info),
+			fs_info->sectorsize);
+
+	/*
+	 * fscrypt sets disk_link.len to be len + 1, including a NUL terminator, but we
+	 * don't store that '\0' character.
+	 */
+	err = fscrypt_prepare_symlink(dir, symname, name_len, max_len + 1,
+				      &disk_link);
+	if (err)
+		return err;
 
 	inode = new_inode(dir->i_sb);
 	if (!inode)
@@ -9401,8 +9436,8 @@ static int btrfs_symlink(struct mnt_idmap *idmap, struct inode *dir,
 	inode->i_op = &btrfs_symlink_inode_operations;
 	inode_nohighmem(inode);
 	inode->i_mapping->a_ops = &btrfs_aops;
-	btrfs_i_size_write(BTRFS_I(inode), name_len);
-	inode_set_bytes(inode, name_len);
+	btrfs_i_size_write(BTRFS_I(inode), disk_link.len - 1);
+	inode_set_bytes(inode, disk_link.len - 1);
 
 	new_inode_args.inode = inode;
 	err = btrfs_new_inode_prepare(&new_inode_args, &trans_num_items);
@@ -9429,10 +9464,23 @@ static int btrfs_symlink(struct mnt_idmap *idmap, struct inode *dir,
 		inode = NULL;
 		goto out;
 	}
+
+	if (IS_ENCRYPTED(inode)) {
+		err = fscrypt_encrypt_symlink(inode, symname, name_len,
+					      &disk_link);
+		if (err) {
+			btrfs_abort_transaction(trans, err);
+			btrfs_free_path(path);
+			discard_new_inode(inode);
+			inode = NULL;
+			goto out;
+		}
+	}
+
 	key.objectid = btrfs_ino(BTRFS_I(inode));
 	key.offset = 0;
 	key.type = BTRFS_EXTENT_DATA_KEY;
-	datasize = btrfs_file_extent_calc_inline_size(name_len);
+	datasize = btrfs_file_extent_calc_inline_size(disk_link.len - 1);
 	err = btrfs_insert_empty_item(trans, root, path, &key,
 				      datasize);
 	if (err) {
@@ -9451,10 +9499,10 @@ static int btrfs_symlink(struct mnt_idmap *idmap, struct inode *dir,
 	btrfs_set_file_extent_encryption(leaf, ei, 0);
 	btrfs_set_file_extent_compression(leaf, ei, 0);
 	btrfs_set_file_extent_other_encoding(leaf, ei, 0);
-	btrfs_set_file_extent_ram_bytes(leaf, ei, name_len);
+	btrfs_set_file_extent_ram_bytes(leaf, ei, disk_link.len - 1);
 
 	ptr = btrfs_file_extent_inline_start(ei);
-	write_extent_buffer(leaf, symname, ptr, name_len);
+	write_extent_buffer(leaf, disk_link.name, ptr, disk_link.len - 1);
 	btrfs_mark_buffer_dirty(trans, leaf);
 	btrfs_free_path(path);
 
@@ -9471,6 +9519,29 @@ static int btrfs_symlink(struct mnt_idmap *idmap, struct inode *dir,
 	return err;
 }
 
+static const char *btrfs_get_link(struct dentry *dentry, struct inode *inode,
+				  struct delayed_call *done)
+{
+	struct page *cpage;
+	const char *paddr;
+	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+
+	if (!IS_ENCRYPTED(inode))
+		return page_get_link(dentry, inode, done);
+
+	if (!dentry)
+		return ERR_PTR(-ECHILD);
+
+	cpage = read_mapping_page(inode->i_mapping, 0, NULL);
+	if (IS_ERR(cpage))
+		return ERR_CAST(cpage);
+
+	paddr = fscrypt_get_symlink(inode, page_address(cpage),
+				    BTRFS_MAX_INLINE_DATA_SIZE(fs_info), done);
+	put_page(cpage);
+	return paddr;
+}
+
 static struct btrfs_trans_handle *insert_prealloc_file_extent(
 				       struct btrfs_trans_handle *trans_in,
 				       struct btrfs_inode *inode,
@@ -10949,7 +11020,7 @@ static const struct inode_operations btrfs_special_inode_operations = {
 	.update_time	= btrfs_update_time,
 };
 static const struct inode_operations btrfs_symlink_inode_operations = {
-	.get_link	= page_get_link,
+	.get_link	= btrfs_get_link,
 	.getattr	= btrfs_getattr,
 	.setattr	= btrfs_setattr,
 	.permission	= btrfs_permission,
@@ -10959,4 +11030,7 @@ static const struct inode_operations btrfs_symlink_inode_operations = {
 
 const struct dentry_operations btrfs_dentry_operations = {
 	.d_delete	= btrfs_dentry_delete,
+#ifdef CONFIG_FS_ENCRYPTION
+	.d_revalidate	= fscrypt_d_revalidate,
+#endif
 };
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index c41ed5a78ea4..21c5358e9202 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -49,6 +49,7 @@
 #include "tests/btrfs-tests.h"
 #include "block-group.h"
 #include "discard.h"
+#include "fscrypt.h"
 #include "qgroup.h"
 #include "raid56.h"
 #include "fs.h"
@@ -1099,6 +1100,7 @@ static int btrfs_fill_super(struct super_block *sb,
 	sb->s_vop = &btrfs_verityops;
 #endif
 	sb->s_xattr = btrfs_xattr_handlers;
+	fscrypt_set_ops(sb, &btrfs_fscrypt_ops);
 	sb->s_time_gran = 1;
 #ifdef CONFIG_BTRFS_FS_POSIX_ACL
 	sb->s_flags |= SB_POSIXACL;
-- 
2.41.0

[PATCH 11/35] btrfs: add inode encryption contexts

[Josef Bacik]

From: Omar Sandoval <osandov@osandov.com>

In order to store encryption information for directories, symlinks,
etc., fscrypt stores a context item with each encrypted non-regular
inode. fscrypt provides an arbitrary blob for the filesystem to store,
and it does not clearly fit into an existing structure, so this goes in
a new item type.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/fscrypt.c              | 117 ++++++++++++++++++++++++++++++++
 fs/btrfs/fscrypt.h              |   2 +
 fs/btrfs/inode.c                |  19 ++++++
 fs/btrfs/ioctl.c                |   8 ++-
 include/uapi/linux/btrfs_tree.h |  10 +++
 5 files changed, 154 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/fscrypt.c b/fs/btrfs/fscrypt.c
index 3a53dc59c1e4..bb3a83d01032 100644
--- a/fs/btrfs/fscrypt.c
+++ b/fs/btrfs/fscrypt.c
@@ -1,8 +1,125 @@
 // SPDX-License-Identifier: GPL-2.0
 
+#include <linux/iversion.h>
 #include "ctree.h"
+#include "accessors.h"
+#include "btrfs_inode.h"
+#include "disk-io.h"
+#include "fs.h"
 #include "fscrypt.h"
+#include "ioctl.h"
+#include "messages.h"
+#include "transaction.h"
+#include "xattr.h"
+
+static int btrfs_fscrypt_get_context(struct inode *inode, void *ctx, size_t len)
+{
+	struct btrfs_key key = {
+		.objectid = btrfs_ino(BTRFS_I(inode)),
+		.type = BTRFS_FSCRYPT_CTX_ITEM_KEY,
+		.offset = 0,
+	};
+	struct btrfs_path *path;
+	struct extent_buffer *leaf;
+	unsigned long ptr;
+	int ret;
+
+
+	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
+
+	ret = btrfs_search_slot(NULL, BTRFS_I(inode)->root, &key, path, 0, 0);
+	if (ret) {
+		len = -ENOENT;
+		goto out;
+	}
+
+	leaf = path->nodes[0];
+	ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
+	/* fscrypt provides max context length, but it could be less */
+	len = min_t(size_t, len, btrfs_item_size(leaf, path->slots[0]));
+	read_extent_buffer(leaf, ctx, ptr, len);
+
+out:
+	btrfs_free_path(path);
+	return len;
+}
+
+static int btrfs_fscrypt_set_context(struct inode *inode, const void *ctx,
+				     size_t len, void *fs_data)
+{
+	struct btrfs_trans_handle *trans = fs_data;
+	struct btrfs_key key = {
+		.objectid = btrfs_ino(BTRFS_I(inode)),
+		.type = BTRFS_FSCRYPT_CTX_ITEM_KEY,
+		.offset = 0,
+	};
+	struct btrfs_path *path = NULL;
+	struct extent_buffer *leaf;
+	unsigned long ptr;
+	int ret;
+
+	if (!trans)
+		trans = btrfs_start_transaction(BTRFS_I(inode)->root, 2);
+	if (IS_ERR(trans))
+		return PTR_ERR(trans);
+
+	path = btrfs_alloc_path();
+	if (!path) {
+		ret = -ENOMEM;
+		goto out_err;
+	}
+
+	ret = btrfs_search_slot(trans, BTRFS_I(inode)->root, &key, path, 0, 1);
+	if (ret < 0)
+		goto out_err;
+
+	if (ret > 0) {
+		btrfs_release_path(path);
+		ret = btrfs_insert_empty_item(trans, BTRFS_I(inode)->root, path, &key, len);
+		if (ret)
+			goto out_err;
+	}
+
+	leaf = path->nodes[0];
+	ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
+
+	len = min_t(size_t, len, btrfs_item_size(leaf, path->slots[0]));
+	write_extent_buffer(leaf, ctx, ptr, len);
+	btrfs_mark_buffer_dirty(trans, leaf);
+	btrfs_release_path(path);
+
+	if (fs_data)
+		return ret;
+
+	BTRFS_I(inode)->flags |= BTRFS_INODE_ENCRYPT;
+	btrfs_sync_inode_flags_to_i_flags(inode);
+	inode_inc_iversion(inode);
+	inode_set_ctime_current(inode);
+	ret = btrfs_update_inode(trans, BTRFS_I(inode));
+	if (ret)
+		goto out_abort;
+	btrfs_free_path(path);
+	btrfs_end_transaction(trans);
+	return 0;
+out_abort:
+	btrfs_abort_transaction(trans, ret);
+out_err:
+	if (!fs_data)
+		btrfs_end_transaction(trans);
+	btrfs_free_path(path);
+	return ret;
+}
+
+static bool btrfs_fscrypt_empty_dir(struct inode *inode)
+{
+	return inode->i_size == BTRFS_EMPTY_DIR_SIZE;
+}
 
 const struct fscrypt_operations btrfs_fscrypt_ops = {
+	.get_context = btrfs_fscrypt_get_context,
+	.set_context = btrfs_fscrypt_set_context,
+	.empty_dir = btrfs_fscrypt_empty_dir,
 	.key_prefix = "btrfs:"
 };
diff --git a/fs/btrfs/fscrypt.h b/fs/btrfs/fscrypt.h
index 7f4e6888bd43..80adb7e56826 100644
--- a/fs/btrfs/fscrypt.h
+++ b/fs/btrfs/fscrypt.h
@@ -5,6 +5,8 @@
 
 #include <linux/fscrypt.h>
 
+#include "fs.h"
+
 extern const struct fscrypt_operations btrfs_fscrypt_ops;
 
 #endif /* BTRFS_FSCRYPT_H */
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 94c2e13934aa..f261113e7242 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -62,6 +62,7 @@
 #include "defrag.h"
 #include "dir-item.h"
 #include "file-item.h"
+#include "fscrypt.h"
 #include "uuid-tree.h"
 #include "ioctl.h"
 #include "file.h"
@@ -6088,6 +6089,9 @@ int btrfs_new_inode_prepare(struct btrfs_new_inode_args *args,
 	struct inode *inode = args->inode;
 	int ret;
 
+	if (fscrypt_is_nokey_name(args->dentry))
+		return -ENOKEY;
+
 	if (!args->orphan) {
 		ret = fscrypt_setup_filename(dir, &args->dentry->d_name, 0,
 					     &args->fname);
@@ -6123,6 +6127,9 @@ int btrfs_new_inode_prepare(struct btrfs_new_inode_args *args,
 	if (dir->i_security)
 		(*trans_num_items)++;
 #endif
+	/* 1 to add fscrypt item */
+	if (args->encrypt)
+		(*trans_num_items)++;
 	if (args->orphan) {
 		/* 1 to add orphan item */
 		(*trans_num_items)++;
@@ -6300,6 +6307,11 @@ int btrfs_create_new_inode(struct btrfs_trans_handle *trans,
 	inode->i_atime = inode->i_mtime;
 	BTRFS_I(inode)->i_otime = inode->i_mtime;
 
+	if (args->encrypt) {
+		BTRFS_I(inode)->flags |= BTRFS_INODE_ENCRYPT;
+		btrfs_sync_inode_flags_to_i_flags(inode);
+	}
+
 	/*
 	 * We're going to fill the inode item now, so at this point the inode
 	 * must be fully initialized.
@@ -6374,6 +6386,13 @@ int btrfs_create_new_inode(struct btrfs_trans_handle *trans,
 			goto discard;
 		}
 	}
+	if (args->encrypt) {
+		ret = fscrypt_set_context(inode, trans);
+		if (ret) {
+			btrfs_abort_transaction(trans, ret);
+			goto discard;
+		}
+	}
 
 	inode_tree_add(BTRFS_I(inode));
 
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 9c05216de36a..ae674c823d14 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -156,6 +156,8 @@ static unsigned int btrfs_inode_flags_to_fsflags(struct btrfs_inode *binode)
 		iflags |= FS_DIRSYNC_FL;
 	if (flags & BTRFS_INODE_NODATACOW)
 		iflags |= FS_NOCOW_FL;
+	if (flags & BTRFS_INODE_ENCRYPT)
+		iflags |= FS_ENCRYPT_FL;
 	if (ro_flags & BTRFS_INODE_RO_VERITY)
 		iflags |= FS_VERITY_FL;
 
@@ -185,12 +187,14 @@ void btrfs_sync_inode_flags_to_i_flags(struct inode *inode)
 		new_fl |= S_NOATIME;
 	if (binode->flags & BTRFS_INODE_DIRSYNC)
 		new_fl |= S_DIRSYNC;
+	if (binode->flags & BTRFS_INODE_ENCRYPT)
+		new_fl |= S_ENCRYPTED;
 	if (binode->ro_flags & BTRFS_INODE_RO_VERITY)
 		new_fl |= S_VERITY;
 
 	set_mask_bits(&inode->i_flags,
 		      S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC |
-		      S_VERITY, new_fl);
+		      S_VERITY | S_ENCRYPTED, new_fl);
 }
 
 /*
@@ -203,7 +207,7 @@ static int check_fsflags(unsigned int old_flags, unsigned int flags)
 		      FS_NOATIME_FL | FS_NODUMP_FL | \
 		      FS_SYNC_FL | FS_DIRSYNC_FL | \
 		      FS_NOCOMP_FL | FS_COMPR_FL |
-		      FS_NOCOW_FL))
+		      FS_NOCOW_FL | FS_ENCRYPT_FL))
 		return -EOPNOTSUPP;
 
 	/* COMPR and NOCOMP on new/old are valid */
diff --git a/include/uapi/linux/btrfs_tree.h b/include/uapi/linux/btrfs_tree.h
index 9fafcaebf44d..50c9e01a3cb4 100644
--- a/include/uapi/linux/btrfs_tree.h
+++ b/include/uapi/linux/btrfs_tree.h
@@ -164,6 +164,8 @@
 #define BTRFS_VERITY_DESC_ITEM_KEY	36
 #define BTRFS_VERITY_MERKLE_ITEM_KEY	37
 
+#define BTRFS_FSCRYPT_CTX_ITEM_KEY	41
+
 #define BTRFS_ORPHAN_ITEM_KEY		48
 /* reserve 2-15 close to the inode for later flexibility */
 
@@ -416,6 +418,7 @@ static inline __u8 btrfs_dir_flags_to_ftype(__u8 flags)
 #define BTRFS_INODE_NOATIME		(1U << 9)
 #define BTRFS_INODE_DIRSYNC		(1U << 10)
 #define BTRFS_INODE_COMPRESS		(1U << 11)
+#define BTRFS_INODE_ENCRYPT	(1U << 12)
 
 #define BTRFS_INODE_ROOT_ITEM_INIT	(1U << 31)
 
@@ -432,6 +435,7 @@ static inline __u8 btrfs_dir_flags_to_ftype(__u8 flags)
 	 BTRFS_INODE_NOATIME |						\
 	 BTRFS_INODE_DIRSYNC |						\
 	 BTRFS_INODE_COMPRESS |						\
+	 BTRFS_INODE_ENCRYPT |						\
 	 BTRFS_INODE_ROOT_ITEM_INIT)
 
 #define BTRFS_INODE_RO_VERITY		(1U << 0)
@@ -1063,6 +1067,12 @@ enum {
 	BTRFS_NR_FILE_EXTENT_TYPES = 3,
 };
 
+enum {
+	BTRFS_ENCRYPTION_NONE,
+	BTRFS_ENCRYPTION_FSCRYPT,
+	BTRFS_NR_ENCRYPTION_TYPES,
+};
+
 struct btrfs_file_extent_item {
 	/*
 	 * transaction id that created this extent
-- 
2.41.0

[PATCH 12/35] btrfs: add new FEATURE_INCOMPAT_ENCRYPT flag

[Josef Bacik]

From: Omar Sandoval <osandov@osandov.com>

As encrypted files will be incompatible with older filesystem versions,
new filesystems should be created with an incompat flag for fscrypt,
which will gate access to the encryption ioctls.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/fs.h              | 3 ++-
 fs/btrfs/super.c           | 5 +++++
 fs/btrfs/sysfs.c           | 6 ++++++
 include/uapi/linux/btrfs.h | 1 +
 4 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/fs.h b/fs/btrfs/fs.h
index 25a43ca4e0dd..cb2b0d442de8 100644
--- a/fs/btrfs/fs.h
+++ b/fs/btrfs/fs.h
@@ -232,7 +232,8 @@ enum {
 #define BTRFS_FEATURE_INCOMPAT_SUPP		\
 	(BTRFS_FEATURE_INCOMPAT_SUPP_STABLE |	\
 	 BTRFS_FEATURE_INCOMPAT_RAID_STRIPE_TREE | \
-	 BTRFS_FEATURE_INCOMPAT_EXTENT_TREE_V2)
+	 BTRFS_FEATURE_INCOMPAT_EXTENT_TREE_V2 | \
+	 BTRFS_FEATURE_INCOMPAT_ENCRYPT)
 
 #else
 
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 21c5358e9202..2b5d60cb7fed 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -2378,6 +2378,11 @@ static int __init btrfs_print_mod_info(void)
 			", fsverity=yes"
 #else
 			", fsverity=no"
+#endif
+#ifdef CONFIG_FS_ENCRYPTION
+			", fscrypt=yes"
+#else
+			", fscrypt=no"
 #endif
 			;
 	pr_info("Btrfs loaded%s\n", options);
diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index 143f0553714b..409244b569a5 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -305,6 +305,9 @@ BTRFS_FEAT_ATTR_INCOMPAT(raid_stripe_tree, RAID_STRIPE_TREE);
 #ifdef CONFIG_FS_VERITY
 BTRFS_FEAT_ATTR_COMPAT_RO(verity, VERITY);
 #endif
+#ifdef CONFIG_FS_ENCRYPTION
+BTRFS_FEAT_ATTR_INCOMPAT(encryption, ENCRYPT);
+#endif /* CONFIG_FS_ENCRYPTION */
 
 /*
  * Features which depend on feature bits and may differ between each fs.
@@ -338,6 +341,9 @@ static struct attribute *btrfs_supported_feature_attrs[] = {
 #ifdef CONFIG_FS_VERITY
 	BTRFS_FEAT_ATTR_PTR(verity),
 #endif
+#ifdef CONFIG_FS_ENCRYPTION
+	BTRFS_FEAT_ATTR_PTR(encryption),
+#endif /* CONFIG_FS_ENCRYPTION */
 	NULL
 };
 
diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h
index e2c106bb0586..3ff21c95e1bb 100644
--- a/include/uapi/linux/btrfs.h
+++ b/include/uapi/linux/btrfs.h
@@ -341,6 +341,7 @@ struct btrfs_ioctl_fs_info_args {
 #define BTRFS_FEATURE_INCOMPAT_ZONED		(1ULL << 12)
 #define BTRFS_FEATURE_INCOMPAT_EXTENT_TREE_V2	(1ULL << 13)
 #define BTRFS_FEATURE_INCOMPAT_RAID_STRIPE_TREE	(1ULL << 14)
+#define BTRFS_FEATURE_INCOMPAT_ENCRYPT		(1ULL << 15)
 #define BTRFS_FEATURE_INCOMPAT_SIMPLE_QUOTA	(1ULL << 16)
 
 struct btrfs_ioctl_feature_flags {
-- 
2.41.0

[PATCH 13/35] btrfs: adapt readdir for encrypted and nokey names

[Josef Bacik]

From: Omar Sandoval <osandov@osandov.com>

Deleting an encrypted file must always be permitted, even if the user
does not have the appropriate key. Therefore, for listing an encrypted
directory, so-called 'nokey' names are provided, and these nokey names
must be sufficient to look up and delete the appropriate encrypted
files. See 'struct fscrypt_nokey_name' for more information on the
format of these names.

The first part of supporting nokey names is allowing lookups by nokey
name. Only a few entry points need to support these: deleting a
directory, file, or subvolume -- each of these call
fscrypt_setup_filename() with a '1' argument, indicating that the key is
not required and therefore a nokey name may be provided. If a nokey name
is provided, the fscrypt_name returned by fscrypt_setup_filename() will
not have its disk_name field populated, but will have various other
fields set.

This change alters the relevant codepaths to pass a complete
fscrypt_name anywhere that it might contain a nokey name. When it does
contain a nokey name, the first time the name is successfully matched to
a stored name populates the disk name field of the fscrypt_name,
allowing the caller to use the normal disk name codepaths afterward.
Otherwise, the matching functionality is in close analogue to the
function fscrypt_match_name().

Functions where most callers are providing a fscrypt_str are duplicated
and adapted for a fscrypt_name, and functions where most callers are
providing a fscrypt_name are changed to so require at all callsites.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/btrfs_inode.h   |   2 +-
 fs/btrfs/delayed-inode.c |  29 ++++++-
 fs/btrfs/delayed-inode.h |   6 +-
 fs/btrfs/dir-item.c      |  77 ++++++++++++++++---
 fs/btrfs/dir-item.h      |  11 ++-
 fs/btrfs/extent_io.c     |  18 +++++
 fs/btrfs/extent_io.h     |   3 +
 fs/btrfs/fscrypt.c       |  34 +++++++++
 fs/btrfs/fscrypt.h       |  19 +++++
 fs/btrfs/inode.c         | 158 ++++++++++++++++++++++++++-------------
 fs/btrfs/root-tree.c     |   8 +-
 fs/btrfs/root-tree.h     |   2 +-
 fs/btrfs/tree-log.c      |   3 +-
 13 files changed, 297 insertions(+), 73 deletions(-)

diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
index 68ebb6096822..93390f12a4ef 100644
--- a/fs/btrfs/btrfs_inode.h
+++ b/fs/btrfs/btrfs_inode.h
@@ -422,7 +422,7 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry);
 int btrfs_set_inode_index(struct btrfs_inode *dir, u64 *index);
 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
 		       struct btrfs_inode *dir, struct btrfs_inode *inode,
-		       const struct fscrypt_str *name);
+		       struct fscrypt_name *name);
 int btrfs_add_link(struct btrfs_trans_handle *trans,
 		   struct btrfs_inode *parent_inode, struct btrfs_inode *inode,
 		   const struct fscrypt_str *name, int add_backref, u64 index);
diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
index 35d7616615c1..43b5fb3fce27 100644
--- a/fs/btrfs/delayed-inode.c
+++ b/fs/btrfs/delayed-inode.c
@@ -1762,7 +1762,9 @@ int btrfs_should_delete_dir_index(struct list_head *del_list,
 /*
  * Read dir info stored in the delayed tree.
  */
-int btrfs_readdir_delayed_dir_index(struct dir_context *ctx,
+int btrfs_readdir_delayed_dir_index(struct inode *inode,
+				    struct fscrypt_str *fstr,
+				    struct dir_context *ctx,
 				    struct list_head *ins_list)
 {
 	struct btrfs_dir_item *di;
@@ -1772,6 +1774,7 @@ int btrfs_readdir_delayed_dir_index(struct dir_context *ctx,
 	int name_len;
 	int over = 0;
 	unsigned char d_type;
+	size_t fstr_len = fstr->len;
 
 	/*
 	 * Changing the data of the delayed item is impossible. So
@@ -1796,8 +1799,28 @@ int btrfs_readdir_delayed_dir_index(struct dir_context *ctx,
 		d_type = fs_ftype_to_dtype(btrfs_dir_flags_to_ftype(di->type));
 		btrfs_disk_key_to_cpu(&location, &di->location);
 
-		over = !dir_emit(ctx, name, name_len,
-			       location.objectid, d_type);
+		if (di->type & BTRFS_FT_ENCRYPTED) {
+			int ret;
+			struct fscrypt_str iname = FSTR_INIT(name, name_len);
+
+			fstr->len = fstr_len;
+			/*
+			 * The hash is only used when the encryption key is not
+			 * available. But if we have delayed insertions, then we
+			 * must have the encryption key available or we wouldn't
+			 * have been able to create entries in the directory.
+			 * So, we don't calculate the hash.
+			 */
+			ret = fscrypt_fname_disk_to_usr(inode, 0, 0, &iname,
+							fstr);
+			if (ret)
+				return ret;
+			over = !dir_emit(ctx, fstr->name, fstr->len,
+					 location.objectid, d_type);
+		} else {
+			over = !dir_emit(ctx, name, name_len, location.objectid,
+					 d_type);
+		}
 
 		if (refcount_dec_and_test(&curr->refs))
 			kfree(curr);
diff --git a/fs/btrfs/delayed-inode.h b/fs/btrfs/delayed-inode.h
index d050e572c7f9..6fe2c7607c8b 100644
--- a/fs/btrfs/delayed-inode.h
+++ b/fs/btrfs/delayed-inode.h
@@ -16,6 +16,8 @@
 #include <linux/refcount.h>
 #include "ctree.h"
 
+struct fscrypt_str;
+
 enum btrfs_delayed_item_type {
 	BTRFS_DELAYED_INSERTION_ITEM,
 	BTRFS_DELAYED_DELETION_ITEM
@@ -155,7 +157,9 @@ void btrfs_readdir_put_delayed_items(struct inode *inode,
 				     struct list_head *del_list);
 int btrfs_should_delete_dir_index(struct list_head *del_list,
 				  u64 index);
-int btrfs_readdir_delayed_dir_index(struct dir_context *ctx,
+int btrfs_readdir_delayed_dir_index(struct inode *inode,
+				    struct fscrypt_str *fstr,
+				    struct dir_context *ctx,
 				    struct list_head *ins_list);
 
 /* Used during directory logging. */
diff --git a/fs/btrfs/dir-item.c b/fs/btrfs/dir-item.c
index 9c07d5c3e5ad..a64cfddff7f0 100644
--- a/fs/btrfs/dir-item.c
+++ b/fs/btrfs/dir-item.c
@@ -6,6 +6,7 @@
 #include "messages.h"
 #include "ctree.h"
 #include "disk-io.h"
+#include "fscrypt.h"
 #include "transaction.h"
 #include "accessors.h"
 #include "dir-item.h"
@@ -230,6 +231,47 @@ struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
 	return di;
 }
 
+/*
+ * Lookup for a directory item by fscrypt_name.
+ *
+ * @trans:	The transaction handle to use.
+ * @root:	The root of the target tree.
+ * @path:	Path to use for the search.
+ * @dir:	The inode number (objectid) of the directory.
+ * @name:	The fscrypt_name associated to the directory entry
+ * @mod:	Used to indicate if the tree search is meant for a read only
+ *		lookup or for a deletion lookup, so its value should be 0 or
+ *		-1, respectively.
+ *
+ * Returns: NULL if the dir item does not exists, an error pointer if an error
+ * happened, or a pointer to a dir item if a dir item exists for the given name.
+ */
+struct btrfs_dir_item *btrfs_lookup_dir_item_fname(struct btrfs_trans_handle *trans,
+						   struct btrfs_root *root,
+						   struct btrfs_path *path, u64 dir,
+						   struct fscrypt_name *name, int mod)
+{
+	struct btrfs_key key;
+	struct btrfs_dir_item *di = NULL;
+	int ret = 0;
+
+	key.objectid = dir;
+	key.type = BTRFS_DIR_ITEM_KEY;
+	key.offset = btrfs_name_hash(name->disk_name.name, name->disk_name.len);
+	/* XXX get the right hash for no-key names */
+
+	ret = btrfs_search_slot(trans, root, &key, path, mod, -mod);
+	if (ret == 0)
+		di = btrfs_match_dir_item_fname(root->fs_info, path, name);
+
+	if (ret == -ENOENT || (di && IS_ERR(di) && PTR_ERR(di) == -ENOENT))
+		return NULL;
+	if (ret < 0)
+		di = ERR_PTR(ret);
+
+	return di;
+}
+
 int btrfs_check_dir_item_collision(struct btrfs_root *root, u64 dir,
 				   const struct fscrypt_str *name)
 {
@@ -287,9 +329,9 @@ int btrfs_check_dir_item_collision(struct btrfs_root *root, u64 dir,
 }
 
 /*
- * Lookup for a directory index item by name and index number.
+ * Lookup for a directory index item by fscrypt_name and index number.
  *
- * @trans:	The transaction handle to use. Can be NULL if @mod is 0.
+ * @trans:	The transaction handle to use.
  * @root:	The root of the target tree.
  * @path:	Path to use for the search.
  * @dir:	The inode number (objectid) of the directory.
@@ -327,7 +369,7 @@ btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
 
 struct btrfs_dir_item *
 btrfs_search_dir_index_item(struct btrfs_root *root, struct btrfs_path *path,
-			    u64 dirid, const struct fscrypt_str *name)
+			    u64 dirid, struct fscrypt_name *name)
 {
 	struct btrfs_dir_item *di;
 	struct btrfs_key key;
@@ -340,9 +382,7 @@ btrfs_search_dir_index_item(struct btrfs_root *root, struct btrfs_path *path,
 	btrfs_for_each_slot(root, &key, &key, path, ret) {
 		if (key.objectid != dirid || key.type != BTRFS_DIR_INDEX_KEY)
 			break;
-
-		di = btrfs_match_dir_item_name(root->fs_info, path,
-					       name->name, name->len);
+		di = btrfs_match_dir_item_fname(root->fs_info, path, name);
 		if (di)
 			return di;
 	}
@@ -378,9 +418,9 @@ struct btrfs_dir_item *btrfs_lookup_xattr(struct btrfs_trans_handle *trans,
  * this walks through all the entries in a dir item and finds one
  * for a specific name.
  */
-struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_fs_info *fs_info,
-						 struct btrfs_path *path,
-						 const char *name, int name_len)
+struct btrfs_dir_item *btrfs_match_dir_item_fname(struct btrfs_fs_info *fs_info,
+						  struct btrfs_path *path,
+						  struct fscrypt_name *name)
 {
 	struct btrfs_dir_item *dir_item;
 	unsigned long name_ptr;
@@ -399,8 +439,8 @@ struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_fs_info *fs_info,
 			btrfs_dir_data_len(leaf, dir_item);
 		name_ptr = (unsigned long)(dir_item + 1);
 
-		if (btrfs_dir_name_len(leaf, dir_item) == name_len &&
-		    memcmp_extent_buffer(leaf, name, name_ptr, name_len) == 0)
+		if (btrfs_fscrypt_match_name(name, leaf, name_ptr,
+					     btrfs_dir_name_len(leaf, dir_item)))
 			return dir_item;
 
 		cur += this_len;
@@ -410,6 +450,21 @@ struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_fs_info *fs_info,
 	return NULL;
 }
 
+/*
+ * helper function to look at the directory item pointed to by 'path'
+ * this walks through all the entries in a dir item and finds one
+ * for a specific name.
+ */
+struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_fs_info *fs_info,
+						 struct btrfs_path *path,
+						 const char *name, int name_len)
+{
+	struct fscrypt_name fname = {
+		.disk_name = FSTR_INIT((char *) name, name_len)
+	};
+	return btrfs_match_dir_item_fname(fs_info, path, &fname);
+}
+
 /*
  * given a pointer into a directory item, delete it.  This
  * handles items that have more than one entry in them.
diff --git a/fs/btrfs/dir-item.h b/fs/btrfs/dir-item.h
index e40a226373d7..1d6ab8c3b879 100644
--- a/fs/btrfs/dir-item.h
+++ b/fs/btrfs/dir-item.h
@@ -6,6 +6,7 @@
 #include <linux/crc32c.h>
 
 struct fscrypt_str;
+struct fscrypt_name;
 
 int btrfs_check_dir_item_collision(struct btrfs_root *root, u64 dir,
 			  const struct fscrypt_str *name);
@@ -16,6 +17,11 @@ struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
 					     struct btrfs_root *root,
 					     struct btrfs_path *path, u64 dir,
 					     const struct fscrypt_str *name, int mod);
+struct btrfs_dir_item *btrfs_lookup_dir_item_fname(
+	struct btrfs_trans_handle *trans,
+	struct btrfs_root *root,
+	struct btrfs_path *path, u64 dir,
+	struct fscrypt_name *name, int mod);
 struct btrfs_dir_item *btrfs_lookup_dir_index_item(
 			struct btrfs_trans_handle *trans,
 			struct btrfs_root *root,
@@ -23,7 +29,7 @@ struct btrfs_dir_item *btrfs_lookup_dir_index_item(
 			u64 index, const struct fscrypt_str *name, int mod);
 struct btrfs_dir_item *btrfs_search_dir_index_item(struct btrfs_root *root,
 			    struct btrfs_path *path, u64 dirid,
-			    const struct fscrypt_str *name);
+			    struct fscrypt_name *name);
 int btrfs_delete_one_dir_name(struct btrfs_trans_handle *trans,
 			      struct btrfs_root *root,
 			      struct btrfs_path *path,
@@ -42,6 +48,9 @@ struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_fs_info *fs_info,
 						 struct btrfs_path *path,
 						 const char *name,
 						 int name_len);
+struct btrfs_dir_item *btrfs_match_dir_item_fname(struct btrfs_fs_info *fs_info,
+						  struct btrfs_path *path,
+						  struct fscrypt_name *name);
 
 static inline u64 btrfs_name_hash(const char *name, int len)
 {
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 90369d132d4f..121746b7ce95 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -4135,6 +4135,24 @@ static void assert_eb_page_uptodate(const struct extent_buffer *eb,
 	}
 }
 
+/* Take a sha256 of a portion of an extent buffer. */
+void extent_buffer_sha256(const struct extent_buffer *eb,
+			  unsigned long start,
+			  unsigned long len, u8 *out)
+{
+	void *eb_addr = btrfs_get_eb_addr(eb);
+
+	if (check_eb_range(eb, start, len))
+		return;
+
+	/*
+	 * TODO: This should maybe be using the crypto API, not the fallback,
+	 * but fscrypt uses the fallback and this is only used in emulation of
+	 * fscrypt's buffer sha256 method.
+	 */
+	sha256(eb_addr + start, len, out);
+}
+
 void write_extent_buffer(const struct extent_buffer *eb, const void *srcv,
 			 unsigned long start, unsigned long len)
 {
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 368ffe00c326..b30b3448b1fb 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -254,6 +254,9 @@ static inline int extent_buffer_uptodate(const struct extent_buffer *eb)
 
 int memcmp_extent_buffer(const struct extent_buffer *eb, const void *ptrv,
 			 unsigned long start, unsigned long len);
+void extent_buffer_sha256(const struct extent_buffer *eb,
+			  unsigned long start,
+			  unsigned long len, u8 *out);
 void read_extent_buffer(const struct extent_buffer *eb, void *dst,
 			unsigned long start,
 			unsigned long len);
diff --git a/fs/btrfs/fscrypt.c b/fs/btrfs/fscrypt.c
index bb3a83d01032..588966f0414f 100644
--- a/fs/btrfs/fscrypt.c
+++ b/fs/btrfs/fscrypt.c
@@ -5,13 +5,47 @@
 #include "accessors.h"
 #include "btrfs_inode.h"
 #include "disk-io.h"
+#include "ioctl.h"
 #include "fs.h"
 #include "fscrypt.h"
 #include "ioctl.h"
 #include "messages.h"
+#include "root-tree.h"
 #include "transaction.h"
 #include "xattr.h"
 
+/*
+ * This function is extremely similar to fscrypt_match_name() but uses an
+ * extent_buffer.
+ */
+bool btrfs_fscrypt_match_name(struct fscrypt_name *fname,
+			      struct extent_buffer *leaf, unsigned long de_name,
+			      u32 de_name_len)
+{
+	const struct fscrypt_nokey_name *nokey_name =
+		(const struct fscrypt_nokey_name *)fname->crypto_buf.name;
+	u8 digest[SHA256_DIGEST_SIZE];
+
+	if (likely(fname->disk_name.name)) {
+		if (de_name_len != fname->disk_name.len)
+			return false;
+		return !memcmp_extent_buffer(leaf, fname->disk_name.name,
+					     de_name, de_name_len);
+	}
+
+	if (de_name_len <= sizeof(nokey_name->bytes))
+		return false;
+
+	if (memcmp_extent_buffer(leaf, nokey_name->bytes, de_name,
+				 sizeof(nokey_name->bytes)))
+		return false;
+
+	extent_buffer_sha256(leaf, de_name + sizeof(nokey_name->bytes),
+			     de_name_len - sizeof(nokey_name->bytes), digest);
+
+	return !memcmp(digest, nokey_name->sha256, sizeof(digest));
+}
+
 static int btrfs_fscrypt_get_context(struct inode *inode, void *ctx, size_t len)
 {
 	struct btrfs_key key = {
diff --git a/fs/btrfs/fscrypt.h b/fs/btrfs/fscrypt.h
index 80adb7e56826..1647bbbcd609 100644
--- a/fs/btrfs/fscrypt.h
+++ b/fs/btrfs/fscrypt.h
@@ -4,9 +4,28 @@
 #define BTRFS_FSCRYPT_H
 
 #include <linux/fscrypt.h>
+#include "extent_io.h"
 
 #include "fs.h"
 
+#ifdef CONFIG_FS_ENCRYPTION
+bool btrfs_fscrypt_match_name(struct fscrypt_name *fname,
+			      struct extent_buffer *leaf,
+			      unsigned long de_name, u32 de_name_len);
+
+#else
+static inline bool btrfs_fscrypt_match_name(struct fscrypt_name *fname,
+					    struct extent_buffer *leaf,
+					    unsigned long de_name,
+					    u32 de_name_len)
+{
+	if (de_name_len != fname_len(fname))
+		return false;
+	return !memcmp_extent_buffer(leaf, fname->disk_name.name, de_name,
+				     de_name_len);
+}
+#endif /* CONFIG_FS_ENCRYPTION */
+
 extern const struct fscrypt_operations btrfs_fscrypt_ops;
 
 #endif /* BTRFS_FSCRYPT_H */
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index f261113e7242..ccbaeea68e2e 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4049,7 +4049,7 @@ int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans,
 static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
 				struct btrfs_inode *dir,
 				struct btrfs_inode *inode,
-				const struct fscrypt_str *name,
+				struct fscrypt_name *name,
 				struct btrfs_rename_ctx *rename_ctx)
 {
 	struct btrfs_root *root = dir->root;
@@ -4067,7 +4067,7 @@ static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
 		goto out;
 	}
 
-	di = btrfs_lookup_dir_item(trans, root, path, dir_ino, name, -1);
+	di = btrfs_lookup_dir_item_fname(trans, root, path, dir_ino, name, -1);
 	if (IS_ERR_OR_NULL(di)) {
 		ret = di ? PTR_ERR(di) : -ENOENT;
 		goto err;
@@ -4095,11 +4095,14 @@ static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
 		}
 	}
 
-	ret = btrfs_del_inode_ref(trans, root, name, ino, dir_ino, &index);
+	ret = btrfs_del_inode_ref(trans, root, &name->disk_name, ino, dir_ino,
+				  &index);
 	if (ret) {
+		/* This should print a base-64 encoded name if relevant? */
 		btrfs_info(fs_info,
 			"failed to delete reference to %.*s, inode %llu parent %llu",
-			name->len, name->name, ino, dir_ino);
+			name->disk_name.len, name->disk_name.name, ino,
+			dir_ino);
 		btrfs_abort_transaction(trans, ret);
 		goto err;
 	}
@@ -4120,8 +4123,10 @@ static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
 	 * operations on the log tree, increasing latency for applications.
 	 */
 	if (!rename_ctx) {
-		btrfs_del_inode_ref_in_log(trans, root, name, inode, dir_ino);
-		btrfs_del_dir_entries_in_log(trans, root, name, dir, index);
+		btrfs_del_inode_ref_in_log(trans, root, &name->disk_name,
+					   inode, dir_ino);
+		btrfs_del_dir_entries_in_log(trans, root, &name->disk_name,
+					     dir, index);
 	}
 
 	/*
@@ -4139,7 +4144,7 @@ static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
 	if (ret)
 		goto out;
 
-	btrfs_i_size_write(dir, dir->vfs_inode.i_size - name->len * 2);
+	btrfs_i_size_write(dir, dir->vfs_inode.i_size - name->disk_name.len * 2);
 	inode_inc_iversion(&inode->vfs_inode);
 	inode_inc_iversion(&dir->vfs_inode);
 	inode_set_ctime_current(&inode->vfs_inode);
@@ -4151,7 +4156,7 @@ static int __btrfs_unlink_inode(struct btrfs_trans_handle *trans,
 
 int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
 		       struct btrfs_inode *dir, struct btrfs_inode *inode,
-		       const struct fscrypt_str *name)
+		       struct fscrypt_name *name)
 {
 	int ret;
 
@@ -4202,7 +4207,7 @@ static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
 				false);
 
 	ret = btrfs_unlink_inode(trans, BTRFS_I(dir), BTRFS_I(d_inode(dentry)),
-				 &fname.disk_name);
+				 &fname);
 	if (ret)
 		goto end_trans;
 
@@ -4239,8 +4244,6 @@ static int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
 	if (ret)
 		return ret;
 
-	/* This needs to handle no-key deletions later on */
-
 	if (btrfs_ino(inode) == BTRFS_FIRST_FREE_OBJECTID) {
 		objectid = inode->root->root_key.objectid;
 	} else if (btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) {
@@ -4257,8 +4260,8 @@ static int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
 		goto out;
 	}
 
-	di = btrfs_lookup_dir_item(trans, root, path, dir_ino,
-				   &fname.disk_name, -1);
+	di = btrfs_lookup_dir_item_fname(trans, root, path, dir_ino,
+					 &fname, -1);
 	if (IS_ERR_OR_NULL(di)) {
 		ret = di ? PTR_ERR(di) : -ENOENT;
 		goto out;
@@ -4284,7 +4287,7 @@ static int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
 	 * call btrfs_del_root_ref, and it _shouldn't_ fail.
 	 */
 	if (btrfs_ino(inode) == BTRFS_EMPTY_SUBVOL_DIR_OBJECTID) {
-		di = btrfs_search_dir_index_item(root, path, dir_ino, &fname.disk_name);
+		di = btrfs_search_dir_index_item(root, path, dir_ino, &fname);
 		if (IS_ERR_OR_NULL(di)) {
 			if (!di)
 				ret = -ENOENT;
@@ -4301,7 +4304,7 @@ static int btrfs_unlink_subvol(struct btrfs_trans_handle *trans,
 	} else {
 		ret = btrfs_del_root_ref(trans, objectid,
 					 root->root_key.objectid, dir_ino,
-					 &index, &fname.disk_name);
+					 &index, &fname);
 		if (ret) {
 			btrfs_abort_transaction(trans, ret);
 			goto out;
@@ -4624,7 +4627,7 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
 
 	/* now the directory is empty */
 	err = btrfs_unlink_inode(trans, BTRFS_I(dir), BTRFS_I(d_inode(dentry)),
-				 &fname.disk_name);
+				 &fname);
 	if (!err) {
 		btrfs_i_size_write(BTRFS_I(inode), 0);
 		/*
@@ -5328,32 +5331,23 @@ void btrfs_evict_inode(struct inode *inode)
  * If no dir entries were found, returns -ENOENT.
  * If found a corrupted location in dir entry, returns -EUCLEAN.
  */
-static int btrfs_inode_by_name(struct btrfs_inode *dir, struct dentry *dentry,
+static int btrfs_inode_by_name(struct btrfs_inode *dir,
+			       struct fscrypt_name *fname,
 			       struct btrfs_key *location, u8 *type)
 {
 	struct btrfs_dir_item *di;
 	struct btrfs_path *path;
 	struct btrfs_root *root = dir->root;
 	int ret = 0;
-	struct fscrypt_name fname;
 
 	path = btrfs_alloc_path();
 	if (!path)
 		return -ENOMEM;
 
-	ret = fscrypt_setup_filename(&dir->vfs_inode, &dentry->d_name, 1, &fname);
-	if (ret < 0)
-		goto out;
-	/*
-	 * fscrypt_setup_filename() should never return a positive value, but
-	 * gcc on sparc/parisc thinks it can, so assert that doesn't happen.
-	 */
-	ASSERT(ret == 0);
-
 	/* This needs to handle no-key deletions later on */
 
-	di = btrfs_lookup_dir_item(NULL, root, path, btrfs_ino(dir),
-				   &fname.disk_name, 0);
+	di = btrfs_lookup_dir_item_fname(NULL, root, path, btrfs_ino(dir),
+				   fname, 0);
 	if (IS_ERR_OR_NULL(di)) {
 		ret = di ? PTR_ERR(di) : -ENOENT;
 		goto out;
@@ -5365,13 +5359,13 @@ static int btrfs_inode_by_name(struct btrfs_inode *dir, struct dentry *dentry,
 		ret = -EUCLEAN;
 		btrfs_warn(root->fs_info,
 "%s gets something invalid in DIR_ITEM (name %s, directory ino %llu, location(%llu %u %llu))",
-			   __func__, fname.disk_name.name, btrfs_ino(dir),
-			   location->objectid, location->type, location->offset);
+			   __func__, fname->usr_fname->name,
+			   btrfs_ino(dir), location->objectid,
+			   location->type, location->offset);
 	}
 	if (!ret)
 		*type = btrfs_dir_ftype(path->nodes[0], di);
 out:
-	fscrypt_free_filename(&fname);
 	btrfs_free_path(path);
 	return ret;
 }
@@ -5644,20 +5638,27 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
 	struct btrfs_root *root = BTRFS_I(dir)->root;
 	struct btrfs_root *sub_root = root;
 	struct btrfs_key location;
+	struct fscrypt_name fname;
 	u8 di_type = 0;
 	int ret = 0;
 
 	if (dentry->d_name.len > BTRFS_NAME_LEN)
 		return ERR_PTR(-ENAMETOOLONG);
 
-	ret = btrfs_inode_by_name(BTRFS_I(dir), dentry, &location, &di_type);
-	if (ret < 0)
+	ret = fscrypt_prepare_lookup(dir, dentry, &fname);
+	if (ret)
 		return ERR_PTR(ret);
 
+	ret = btrfs_inode_by_name(BTRFS_I(dir), &fname, &location, &di_type);
+	if (ret < 0) {
+		inode = ERR_PTR(ret);
+		goto cleanup;
+	}
+
 	if (location.type == BTRFS_INODE_ITEM_KEY) {
 		inode = btrfs_iget(dir->i_sb, location.objectid, root);
 		if (IS_ERR(inode))
-			return inode;
+			goto cleanup;
 
 		/* Do extra check against inode mode with di_type */
 		if (btrfs_inode_type(inode) != di_type) {
@@ -5666,9 +5667,10 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
 				  inode->i_mode, btrfs_inode_type(inode),
 				  di_type);
 			iput(inode);
-			return ERR_PTR(-EUCLEAN);
+			inode = ERR_PTR(-EUCLEAN);
+			goto cleanup;
 		}
-		return inode;
+		goto cleanup;
 	}
 
 	ret = fixup_tree_root_location(fs_info, BTRFS_I(dir), dentry,
@@ -5683,7 +5685,7 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
 		btrfs_put_root(sub_root);
 
 		if (IS_ERR(inode))
-			return inode;
+			goto cleanup;
 
 		down_read(&fs_info->cleanup_work_sem);
 		if (!sb_rdonly(inode->i_sb))
@@ -5695,6 +5697,8 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
 		}
 	}
 
+cleanup:
+	fscrypt_free_filename(&fname);
 	return inode;
 }
 
@@ -5883,18 +5887,32 @@ static int btrfs_real_readdir(struct file *file, struct dir_context *ctx)
 	LIST_HEAD(del_list);
 	int ret;
 	char *name_ptr;
-	int name_len;
+	u32 name_len;
 	int entries = 0;
 	int total_len = 0;
 	bool put = false;
 	struct btrfs_key location;
+	struct fscrypt_str fstr = FSTR_INIT(NULL, 0);
+	u32 fstr_len = 0;
 
 	if (!dir_emit_dots(file, ctx))
 		return 0;
 
+	if (BTRFS_I(inode)->flags & BTRFS_INODE_ENCRYPT) {
+		ret = fscrypt_prepare_readdir(inode);
+		if (ret)
+			return ret;
+		ret = fscrypt_fname_alloc_buffer(BTRFS_NAME_LEN, &fstr);
+		if (ret)
+			return ret;
+		fstr_len = fstr.len;
+	}
+
 	path = btrfs_alloc_path();
-	if (!path)
-		return -ENOMEM;
+	if (!path) {
+		ret = -ENOMEM;
+		goto err_fstr;
+	}
 
 	addr = private->filldir_buf;
 	path->reada = READA_FORWARD;
@@ -5911,6 +5929,7 @@ static int btrfs_real_readdir(struct file *file, struct dir_context *ctx)
 		struct dir_entry *entry;
 		struct extent_buffer *leaf = path->nodes[0];
 		u8 ftype;
+		u32 nokey_len;
 
 		if (found_key.objectid != key.objectid)
 			break;
@@ -5924,8 +5943,13 @@ static int btrfs_real_readdir(struct file *file, struct dir_context *ctx)
 			continue;
 		di = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dir_item);
 		name_len = btrfs_dir_name_len(leaf, di);
-		if ((total_len + sizeof(struct dir_entry) + name_len) >=
-		    PAGE_SIZE) {
+		nokey_len = DIV_ROUND_UP(name_len * 4, 3);
+		/*
+		 * If name is encrypted, and we don't have the key, we could
+		 * need up to 4/3rds the bytes to print it.
+		 */
+		if ((total_len + sizeof(struct dir_entry) + nokey_len)
+		    >= PAGE_SIZE) {
 			btrfs_release_path(path);
 			ret = btrfs_filldir(private->filldir_buf, entries, ctx);
 			if (ret)
@@ -5939,8 +5963,36 @@ static int btrfs_real_readdir(struct file *file, struct dir_context *ctx)
 		ftype = btrfs_dir_flags_to_ftype(btrfs_dir_flags(leaf, di));
 		entry = addr;
 		name_ptr = (char *)(entry + 1);
-		read_extent_buffer(leaf, name_ptr,
-				   (unsigned long)(di + 1), name_len);
+		if (btrfs_dir_flags(leaf, di) & BTRFS_FT_ENCRYPTED) {
+			struct fscrypt_str oname = FSTR_INIT(name_ptr,
+							     nokey_len);
+			u32 hash = 0, minor_hash = 0;
+
+			read_extent_buffer(leaf, fstr.name,
+					   (unsigned long)(di + 1), name_len);
+			fstr.len = name_len;
+			/*
+			 * We're iterating through DIR_INDEX items, so we don't
+			 * have the DIR_ITEM hash handy. Only compute it if
+			 * we'll need it -- the nokey name stores it, so that
+			 * we can look up the appropriate item by nokey name
+			 * later on.
+			 */
+			if (!fscrypt_has_encryption_key(inode)) {
+				u64 name_hash = btrfs_name_hash(fstr.name,
+								fstr.len);
+				hash = name_hash;
+				minor_hash = name_hash >> 32;
+			}
+			ret = fscrypt_fname_disk_to_usr(inode, hash, minor_hash,
+							&fstr, &oname);
+			if (ret)
+				goto err;
+			name_len = oname.len;
+		} else {
+			read_extent_buffer(leaf, name_ptr,
+					   (unsigned long)(di + 1), name_len);
+		}
 		put_unaligned(name_len, &entry->name_len);
 		put_unaligned(fs_ftype_to_dtype(ftype), &entry->type);
 		btrfs_dir_item_key_to_cpu(leaf, di, &location);
@@ -5960,7 +6012,8 @@ static int btrfs_real_readdir(struct file *file, struct dir_context *ctx)
 	if (ret)
 		goto nopos;
 
-	ret = btrfs_readdir_delayed_dir_index(ctx, &ins_list);
+	fstr.len = fstr_len;
+	ret = btrfs_readdir_delayed_dir_index(inode, &fstr, ctx, &ins_list);
 	if (ret)
 		goto nopos;
 
@@ -5991,6 +6044,8 @@ static int btrfs_real_readdir(struct file *file, struct dir_context *ctx)
 	if (put)
 		btrfs_readdir_put_delayed_items(inode, &ins_list, &del_list);
 	btrfs_free_path(path);
+err_fstr:
+	fscrypt_fname_free_buffer(&fstr);
 	return ret;
 }
 
@@ -6441,6 +6496,7 @@ int btrfs_add_link(struct btrfs_trans_handle *trans,
 	struct btrfs_root *root = parent_inode->root;
 	u64 ino = btrfs_ino(inode);
 	u64 parent_ino = btrfs_ino(parent_inode);
+	struct fscrypt_name fname = { .disk_name = *name };
 
 	if (unlikely(ino == BTRFS_FIRST_FREE_OBJECTID)) {
 		memcpy(&key, &inode->root->root_key, sizeof(key));
@@ -6496,7 +6552,7 @@ int btrfs_add_link(struct btrfs_trans_handle *trans,
 		int err;
 		err = btrfs_del_root_ref(trans, key.objectid,
 					 root->root_key.objectid, parent_ino,
-					 &local_index, name);
+					 &local_index, &fname);
 		if (err)
 			btrfs_abort_transaction(trans, err);
 	} else if (add_backref) {
@@ -8863,7 +8919,7 @@ static int btrfs_rename_exchange(struct inode *old_dir,
 	} else { /* src is an inode */
 		ret = __btrfs_unlink_inode(trans, BTRFS_I(old_dir),
 					   BTRFS_I(old_dentry->d_inode),
-					   old_name, &old_rename_ctx);
+					   &old_fname, &old_rename_ctx);
 		if (!ret)
 			ret = btrfs_update_inode(trans, BTRFS_I(old_inode));
 	}
@@ -8878,7 +8934,7 @@ static int btrfs_rename_exchange(struct inode *old_dir,
 	} else { /* dest is an inode */
 		ret = __btrfs_unlink_inode(trans, BTRFS_I(new_dir),
 					   BTRFS_I(new_dentry->d_inode),
-					   new_name, &new_rename_ctx);
+					   &new_fname, &new_rename_ctx);
 		if (!ret)
 			ret = btrfs_update_inode(trans, BTRFS_I(new_inode));
 	}
@@ -9123,7 +9179,7 @@ static int btrfs_rename(struct mnt_idmap *idmap,
 	} else {
 		ret = __btrfs_unlink_inode(trans, BTRFS_I(old_dir),
 					   BTRFS_I(d_inode(old_dentry)),
-					   &old_fname.disk_name, &rename_ctx);
+					   &old_fname, &rename_ctx);
 		if (!ret)
 			ret = btrfs_update_inode(trans, BTRFS_I(old_inode));
 	}
@@ -9141,7 +9197,7 @@ static int btrfs_rename(struct mnt_idmap *idmap,
 		} else {
 			ret = btrfs_unlink_inode(trans, BTRFS_I(new_dir),
 						 BTRFS_I(d_inode(new_dentry)),
-						 &new_fname.disk_name);
+						 &new_fname);
 		}
 		if (!ret && new_inode->i_nlink == 0)
 			ret = btrfs_orphan_add(trans,
diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c
index 603ad1459368..d131934123f5 100644
--- a/fs/btrfs/root-tree.c
+++ b/fs/btrfs/root-tree.c
@@ -10,6 +10,7 @@
 #include "messages.h"
 #include "transaction.h"
 #include "disk-io.h"
+#include "fscrypt.h"
 #include "print-tree.h"
 #include "qgroup.h"
 #include "space-info.h"
@@ -334,7 +335,7 @@ int btrfs_del_root(struct btrfs_trans_handle *trans,
 
 int btrfs_del_root_ref(struct btrfs_trans_handle *trans, u64 root_id,
 		       u64 ref_id, u64 dirid, u64 *sequence,
-		       const struct fscrypt_str *name)
+		       struct fscrypt_name *name)
 {
 	struct btrfs_root *tree_root = trans->fs_info->tree_root;
 	struct btrfs_path *path;
@@ -356,13 +357,14 @@ int btrfs_del_root_ref(struct btrfs_trans_handle *trans, u64 root_id,
 	if (ret < 0) {
 		goto out;
 	} else if (ret == 0) {
+		u32 name_len;
 		leaf = path->nodes[0];
 		ref = btrfs_item_ptr(leaf, path->slots[0],
 				     struct btrfs_root_ref);
 		ptr = (unsigned long)(ref + 1);
+		name_len = btrfs_root_ref_name_len(leaf, ref);
 		if ((btrfs_root_ref_dirid(leaf, ref) != dirid) ||
-		    (btrfs_root_ref_name_len(leaf, ref) != name->len) ||
-		    memcmp_extent_buffer(leaf, name->name, ptr, name->len)) {
+		    !btrfs_fscrypt_match_name(name, leaf, ptr, name_len)) {
 			ret = -ENOENT;
 			goto out;
 		}
diff --git a/fs/btrfs/root-tree.h b/fs/btrfs/root-tree.h
index 8b2c3859e464..5ba7b36cf826 100644
--- a/fs/btrfs/root-tree.h
+++ b/fs/btrfs/root-tree.h
@@ -15,7 +15,7 @@ int btrfs_add_root_ref(struct btrfs_trans_handle *trans, u64 root_id,
 		       const struct fscrypt_str *name);
 int btrfs_del_root_ref(struct btrfs_trans_handle *trans, u64 root_id,
 		       u64 ref_id, u64 dirid, u64 *sequence,
-		       const struct fscrypt_str *name);
+		       struct fscrypt_name *name);
 int btrfs_del_root(struct btrfs_trans_handle *trans, const struct btrfs_key *key);
 int btrfs_insert_root(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 		      const struct btrfs_key *key,
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index c4d8900f91bb..cc262305f4c5 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -901,9 +901,10 @@ static int unlink_inode_for_log_replay(struct btrfs_trans_handle *trans,
 				       struct btrfs_inode *inode,
 				       const struct fscrypt_str *name)
 {
+	struct fscrypt_name fname = { .disk_name = *name, };
 	int ret;
 
-	ret = btrfs_unlink_inode(trans, dir, inode, name);
+	ret = btrfs_unlink_inode(trans, dir, inode, &fname);
 	if (ret)
 		return ret;
 	/*
-- 
2.41.0

[PATCH 14/35] btrfs: handle nokey names.

[Josef Bacik]

From: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>

For encrypted or unencrypted names, we calculate the offset for the dir
item by hashing the name for the dir item. However, this doesn't work
for a long nokey name, where we do not have the complete ciphertext.
Instead, fscrypt stores the filesystem-provided hash in the nokey name,
and we can extract it from the fscrypt_name structure in such a case.

Additionally, for nokey names, if we find the nokey name on disk we can
update the fscrypt_name with the disk name, so add that to searching for
diritems.

Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/dir-item.c | 37 +++++++++++++++++++++++++++++++++++--
 fs/btrfs/fscrypt.c  | 27 +++++++++++++++++++++++++++
 fs/btrfs/fscrypt.h  | 11 +++++++++++
 3 files changed, 73 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/dir-item.c b/fs/btrfs/dir-item.c
index a64cfddff7f0..897fb5477369 100644
--- a/fs/btrfs/dir-item.c
+++ b/fs/btrfs/dir-item.c
@@ -231,6 +231,28 @@ struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
 	return di;
 }
 
+/*
+ * If appropriate, populate the disk name for a fscrypt_name looked up without
+ * a key.
+ *
+ * @path:	The path to the extent buffer in which the name was found.
+ * @di:		The dir item corresponding.
+ * @fname:	The fscrypt_name to perhaps populate.
+ *
+ * Returns: 0 if the name is already populated or the dir item doesn't exist
+ * or the name was successfully populated, else an error code.
+ */
+static int ensure_disk_name_from_dir_item(struct btrfs_path *path,
+					  struct btrfs_dir_item *di,
+					  struct fscrypt_name *name)
+{
+	if (name->disk_name.name || !di)
+		return 0;
+
+	return btrfs_fscrypt_get_disk_name(path->nodes[0], di,
+					   &name->disk_name);
+}
+
 /*
  * Lookup for a directory item by fscrypt_name.
  *
@@ -257,8 +279,12 @@ struct btrfs_dir_item *btrfs_lookup_dir_item_fname(struct btrfs_trans_handle *tr
 
 	key.objectid = dir;
 	key.type = BTRFS_DIR_ITEM_KEY;
-	key.offset = btrfs_name_hash(name->disk_name.name, name->disk_name.len);
-	/* XXX get the right hash for no-key names */
+
+	if (!name->disk_name.name)
+		key.offset = name->hash | ((u64)name->minor_hash << 32);
+	else
+		key.offset = btrfs_name_hash(name->disk_name.name,
+					     name->disk_name.len);
 
 	ret = btrfs_search_slot(trans, root, &key, path, mod, -mod);
 	if (ret == 0)
@@ -266,6 +292,8 @@ struct btrfs_dir_item *btrfs_lookup_dir_item_fname(struct btrfs_trans_handle *tr
 
 	if (ret == -ENOENT || (di && IS_ERR(di) && PTR_ERR(di) == -ENOENT))
 		return NULL;
+	if (ret == 0)
+		ret = ensure_disk_name_from_dir_item(path, di, name);
 	if (ret < 0)
 		di = ERR_PTR(ret);
 
@@ -382,7 +410,12 @@ btrfs_search_dir_index_item(struct btrfs_root *root, struct btrfs_path *path,
 	btrfs_for_each_slot(root, &key, &key, path, ret) {
 		if (key.objectid != dirid || key.type != BTRFS_DIR_INDEX_KEY)
 			break;
+
 		di = btrfs_match_dir_item_fname(root->fs_info, path, name);
+		if (di)
+			ret = ensure_disk_name_from_dir_item(path, di, name);
+		if (ret)
+			break;
 		if (di)
 			return di;
 	}
diff --git a/fs/btrfs/fscrypt.c b/fs/btrfs/fscrypt.c
index 588966f0414f..254e48005aec 100644
--- a/fs/btrfs/fscrypt.c
+++ b/fs/btrfs/fscrypt.c
@@ -14,6 +14,33 @@
 #include "transaction.h"
 #include "xattr.h"
 
+/*
+ * From a given location in a leaf, read a name into a qstr (usually a
+ * fscrypt_name's disk_name), allocating the required buffer. Used for
+ * nokey names.
+ */
+int btrfs_fscrypt_get_disk_name(struct extent_buffer *leaf,
+				struct btrfs_dir_item *dir_item,
+				struct fscrypt_str *name)
+{
+	unsigned long de_name_len = btrfs_dir_name_len(leaf, dir_item);
+	unsigned long de_name = (unsigned long)(dir_item + 1);
+	/*
+	 * For no-key names, we use this opportunity to find the disk
+	 * name, so future searches don't need to deal with nokey names
+	 * and we know what the encrypted size is.
+	 */
+	name->name = kmalloc(de_name_len, GFP_NOFS);
+
+	if (!name->name)
+		return -ENOMEM;
+
+	read_extent_buffer(leaf, name->name, de_name, de_name_len);
+
+	name->len = de_name_len;
+	return 0;
+}
+
 /*
  * This function is extremely similar to fscrypt_match_name() but uses an
  * extent_buffer.
diff --git a/fs/btrfs/fscrypt.h b/fs/btrfs/fscrypt.h
index 1647bbbcd609..c08fd52c99b4 100644
--- a/fs/btrfs/fscrypt.h
+++ b/fs/btrfs/fscrypt.h
@@ -9,11 +9,22 @@
 #include "fs.h"
 
 #ifdef CONFIG_FS_ENCRYPTION
+int btrfs_fscrypt_get_disk_name(struct extent_buffer *leaf,
+				struct btrfs_dir_item *di,
+				struct fscrypt_str *qstr);
+
 bool btrfs_fscrypt_match_name(struct fscrypt_name *fname,
 			      struct extent_buffer *leaf,
 			      unsigned long de_name, u32 de_name_len);
 
 #else
+static inline int btrfs_fscrypt_get_disk_name(struct extent_buffer *leaf,
+					      struct btrfs_dir_item *di,
+					      struct fscrypt_str *qstr)
+{
+	return 0;
+}
+
 static inline bool btrfs_fscrypt_match_name(struct fscrypt_name *fname,
 					    struct extent_buffer *leaf,
 					    unsigned long de_name,
-- 
2.41.0

[PATCH 15/35] btrfs: implement fscrypt ioctls

[Josef Bacik]

From: Omar Sandoval <osandov@osandov.com>

These ioctls allow encryption to actually be used.

The set_encryption_policy ioctl is the thing which actually turns on
encryption, and therefore sets the ENCRYPT flag in the superblock. This
prevents the filesystem from being loaded on older kernels.

fscrypt provides CONFIG_FS_ENCRYPTION-disabled versions of all these
functions which just return -EOPNOTSUPP, so the ioctls don't need to be
compiled out if CONFIG_FS_ENCRYPTION isn't enabled.

We could instead gate this ioctl on the superblock having the flag set,
if we wanted to require mkfs with the encrypt flag in order to have a
filesystem with any encryption.

Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/ioctl.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index ae674c823d14..ddc2d2c7fc7f 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -4587,6 +4587,34 @@ long btrfs_ioctl(struct file *file, unsigned int
 		return btrfs_ioctl_get_fslabel(fs_info, argp);
 	case FS_IOC_SETFSLABEL:
 		return btrfs_ioctl_set_fslabel(file, argp);
+	case FS_IOC_SET_ENCRYPTION_POLICY: {
+		if (!IS_ENABLED(CONFIG_FS_ENCRYPTION))
+			return -EOPNOTSUPP;
+		if (sb_rdonly(fs_info->sb))
+			return -EROFS;
+		/*
+		 *  If we crash before we commit, nothing encrypted could have
+		 * been written so it doesn't matter whether the encrypted
+		 * state persists.
+		 */
+		btrfs_set_fs_incompat(fs_info, ENCRYPT);
+		return fscrypt_ioctl_set_policy(file, (const void __user *)arg);
+	}
+	case FS_IOC_GET_ENCRYPTION_POLICY:
+		return fscrypt_ioctl_get_policy(file, (void __user *)arg);
+	case FS_IOC_GET_ENCRYPTION_POLICY_EX:
+		return fscrypt_ioctl_get_policy_ex(file, (void __user *)arg);
+	case FS_IOC_ADD_ENCRYPTION_KEY:
+		return fscrypt_ioctl_add_key(file, (void __user *)arg);
+	case FS_IOC_REMOVE_ENCRYPTION_KEY:
+		return fscrypt_ioctl_remove_key(file, (void __user *)arg);
+	case FS_IOC_REMOVE_ENCRYPTION_KEY_ALL_USERS:
+		return fscrypt_ioctl_remove_key_all_users(file,
+							  (void __user *)arg);
+	case FS_IOC_GET_ENCRYPTION_KEY_STATUS:
+		return fscrypt_ioctl_get_key_status(file, (void __user *)arg);
+	case FS_IOC_GET_ENCRYPTION_NONCE:
+		return fscrypt_ioctl_get_nonce(file, (void __user *)arg);
 	case FITRIM:
 		return btrfs_ioctl_fitrim(fs_info, argp);
 	case BTRFS_IOC_SNAP_CREATE:
-- 
2.41.0

[PATCH 16/35] btrfs: add encryption to CONFIG_BTRFS_DEBUG

[Josef Bacik]

From: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>

Since encryption is currently under BTRFS_DEBUG, this adds its
dependencies: inline encryption from fscrypt, and the inline encryption
fallback path from the block layer.

Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/ioctl.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index ddc2d2c7fc7f..8e5f9dbb547a 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -4587,6 +4587,7 @@ long btrfs_ioctl(struct file *file, unsigned int
 		return btrfs_ioctl_get_fslabel(fs_info, argp);
 	case FS_IOC_SETFSLABEL:
 		return btrfs_ioctl_set_fslabel(file, argp);
+#ifdef CONFIG_BTRFS_DEBUG
 	case FS_IOC_SET_ENCRYPTION_POLICY: {
 		if (!IS_ENABLED(CONFIG_FS_ENCRYPTION))
 			return -EOPNOTSUPP;
@@ -4615,6 +4616,7 @@ long btrfs_ioctl(struct file *file, unsigned int
 		return fscrypt_ioctl_get_key_status(file, (void __user *)arg);
 	case FS_IOC_GET_ENCRYPTION_NONCE:
 		return fscrypt_ioctl_get_nonce(file, (void __user *)arg);
+#endif /* CONFIG_BTRFS_DEBUG */
 	case FITRIM:
 		return btrfs_ioctl_fitrim(fs_info, argp);
 	case BTRFS_IOC_SNAP_CREATE:
-- 
2.41.0

[PATCH 17/35] btrfs: add get_devices hook for fscrypt

[Josef Bacik]

From: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>

Since extent encryption requires inline encryption, even though we
expect to use the inlinecrypt software fallback most of the time, we
need to enumerate all the devices in use by btrfs.

Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/fscrypt.c | 37 +++++++++++++++++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/fs/btrfs/fscrypt.c b/fs/btrfs/fscrypt.c
index 254e48005aec..4fe0a8804ac5 100644
--- a/fs/btrfs/fscrypt.c
+++ b/fs/btrfs/fscrypt.c
@@ -11,7 +11,9 @@
 #include "ioctl.h"
 #include "messages.h"
 #include "root-tree.h"
+#include "super.h"
 #include "transaction.h"
+#include "volumes.h"
 #include "xattr.h"
 
 /*
@@ -178,9 +180,44 @@ static bool btrfs_fscrypt_empty_dir(struct inode *inode)
 	return inode->i_size == BTRFS_EMPTY_DIR_SIZE;
 }
 
+static struct block_device **btrfs_fscrypt_get_devices(struct super_block *sb,
+						       unsigned int *num_devs)
+{
+	struct btrfs_fs_info *fs_info = btrfs_sb(sb);
+	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
+	int nr_devices = fs_devices->open_devices;
+	struct block_device **devs;
+	struct btrfs_device *device;
+	int i = 0;
+
+	devs = kmalloc_array(nr_devices, sizeof(*devs), GFP_NOFS | GFP_NOWAIT);
+	if (!devs)
+		return ERR_PTR(-ENOMEM);
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
+		if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA,
+						&device->dev_state) ||
+		    !device->bdev ||
+		    test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state))
+			continue;
+
+		devs[i++] = device->bdev;
+
+		if (i >= nr_devices)
+			break;
+
+	}
+	rcu_read_unlock();
+
+	*num_devs = i;
+	return devs;
+}
+
 const struct fscrypt_operations btrfs_fscrypt_ops = {
 	.get_context = btrfs_fscrypt_get_context,
 	.set_context = btrfs_fscrypt_set_context,
 	.empty_dir = btrfs_fscrypt_empty_dir,
+	.get_devices = btrfs_fscrypt_get_devices,
 	.key_prefix = "btrfs:"
 };
-- 
2.41.0

[PATCH 18/35] btrfs: turn on inlinecrypt mount option for encrypt

[Josef Bacik]

From: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>

fscrypt's extent encryption requires the use of inline encryption or the
software fallback that the block layer provides; it is rather
complicated to allow software encryption with extent encryption due to
the timing of memory allocations. Thus, if btrfs has ever had a
encrypted file, or when encryption is enabled on a directory, update the
mount flags to include inlinecrypt.

Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/ioctl.c |  3 +++
 fs/btrfs/super.c | 10 ++++++++++
 2 files changed, 13 insertions(+)

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 8e5f9dbb547a..33bf4d9416a9 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -4599,6 +4599,9 @@ long btrfs_ioctl(struct file *file, unsigned int
 		 * state persists.
 		 */
 		btrfs_set_fs_incompat(fs_info, ENCRYPT);
+		if (!(inode->i_sb->s_flags & SB_INLINECRYPT)) {
+			inode->i_sb->s_flags |= SB_INLINECRYPT;
+		}
 		return fscrypt_ioctl_set_policy(file, (const void __user *)arg);
 	}
 	case FS_IOC_GET_ENCRYPTION_POLICY:
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 2b5d60cb7fed..a8a609f4a9f4 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -1120,6 +1120,16 @@ static int btrfs_fill_super(struct super_block *sb,
 		return err;
 	}
 
+	if (btrfs_fs_incompat(fs_info, ENCRYPT)) {
+		if (IS_ENABLED(CONFIG_FS_ENCRYPTION_INLINE_CRYPT)) {
+			sb->s_flags |= SB_INLINECRYPT;
+		} else {
+			btrfs_err(fs_info, "encryption not supported");
+			err = -EINVAL;
+			goto fail_close;
+		}
+	}
+
 	inode = btrfs_iget(sb, BTRFS_FIRST_FREE_OBJECTID, fs_info->fs_root);
 	if (IS_ERR(inode)) {
 		err = PTR_ERR(inode);
-- 
2.41.0

[PATCH 19/35] btrfs: set file extent encryption excplicitly

[Josef Bacik]

From: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>

This puts the long-preserved 1-byte encryption field to work, storing
whether the extent is encrypted.  Update the tree-checker to allow for
the encryption bit to be set to our valid types.

Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/accessors.h            | 2 ++
 fs/btrfs/inode.c                | 8 ++++++--
 fs/btrfs/tree-checker.c         | 8 +++++---
 fs/btrfs/tree-log.c             | 2 ++
 include/uapi/linux/btrfs_tree.h | 8 +++++++-
 5 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/fs/btrfs/accessors.h b/fs/btrfs/accessors.h
index b780d9087490..5627f13a3d3e 100644
--- a/fs/btrfs/accessors.h
+++ b/fs/btrfs/accessors.h
@@ -951,6 +951,8 @@ BTRFS_SETGET_STACK_FUNCS(stack_file_extent_disk_num_bytes,
 			 struct btrfs_file_extent_item, disk_num_bytes, 64);
 BTRFS_SETGET_STACK_FUNCS(stack_file_extent_compression,
 			 struct btrfs_file_extent_item, compression, 8);
+BTRFS_SETGET_STACK_FUNCS(stack_file_extent_encryption,
+			 struct btrfs_file_extent_item, encryption, 8);
 
 
 BTRFS_SETGET_FUNCS(file_extent_type, struct btrfs_file_extent_item, type, 8);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index ccbaeea68e2e..db053b392d26 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2993,7 +2993,9 @@ static int insert_ordered_extent_file_extent(struct btrfs_trans_handle *trans,
 	btrfs_set_stack_file_extent_num_bytes(&stack_fi, num_bytes);
 	btrfs_set_stack_file_extent_ram_bytes(&stack_fi, ram_bytes);
 	btrfs_set_stack_file_extent_compression(&stack_fi, oe->compress_type);
-	/* Encryption and other encoding is reserved and all 0 */
+	btrfs_set_stack_file_extent_encryption(&stack_fi,
+					       BTRFS_ENCRYPTION_NONE);
+	/* Other encoding is reserved and always 0 */
 
 	/*
 	 * For delalloc, when completing an ordered extent we update the inode's
@@ -9640,7 +9642,9 @@ static struct btrfs_trans_handle *insert_prealloc_file_extent(
 	btrfs_set_stack_file_extent_num_bytes(&stack_fi, len);
 	btrfs_set_stack_file_extent_ram_bytes(&stack_fi, len);
 	btrfs_set_stack_file_extent_compression(&stack_fi, BTRFS_COMPRESS_NONE);
-	/* Encryption and other encoding is reserved and all 0 */
+	btrfs_set_stack_file_extent_encryption(&stack_fi,
+					       BTRFS_ENCRYPTION_NONE);
+	/* Other encoding is reserved and always 0 */
 
 	qgroup_released = btrfs_qgroup_release_data(inode, file_offset, len);
 	if (qgroup_released < 0)
diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c
index 1f2c389b0bfa..c2afdf65c2bf 100644
--- a/fs/btrfs/tree-checker.c
+++ b/fs/btrfs/tree-checker.c
@@ -210,6 +210,7 @@ static int check_extent_data_item(struct extent_buffer *leaf,
 	u32 sectorsize = fs_info->sectorsize;
 	u32 item_size = btrfs_item_size(leaf, slot);
 	u64 extent_end;
+	u8 policy;
 
 	if (unlikely(!IS_ALIGNED(key->offset, sectorsize))) {
 		file_extent_err(leaf, slot,
@@ -261,10 +262,11 @@ static int check_extent_data_item(struct extent_buffer *leaf,
 			BTRFS_NR_COMPRESS_TYPES - 1);
 		return -EUCLEAN;
 	}
-	if (unlikely(btrfs_file_extent_encryption(leaf, fi))) {
+	policy = btrfs_file_extent_encryption(leaf, fi);
+	if (unlikely(policy >= BTRFS_NR_ENCRYPTION_TYPES)) {
 		file_extent_err(leaf, slot,
-			"invalid encryption for file extent, have %u expect 0",
-			btrfs_file_extent_encryption(leaf, fi));
+			"invalid encryption for file extent, have %u expect range [0, %u]",
+			policy, BTRFS_NR_ENCRYPTION_TYPES - 1);
 		return -EUCLEAN;
 	}
 	if (btrfs_file_extent_type(leaf, fi) == BTRFS_FILE_EXTENT_INLINE) {
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index cc262305f4c5..f6f45a0f1b1e 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -4630,6 +4630,7 @@ static int log_one_extent(struct btrfs_trans_handle *trans,
 	u64 extent_offset = em->start - em->orig_start;
 	u64 block_len;
 	int ret;
+	u8 encryption = BTRFS_ENCRYPTION_NONE;
 
 	btrfs_set_stack_file_extent_generation(&fi, trans->transid);
 	if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
@@ -4651,6 +4652,7 @@ static int log_one_extent(struct btrfs_trans_handle *trans,
 	btrfs_set_stack_file_extent_num_bytes(&fi, em->len);
 	btrfs_set_stack_file_extent_ram_bytes(&fi, em->ram_bytes);
 	btrfs_set_stack_file_extent_compression(&fi, em->compress_type);
+	btrfs_set_stack_file_extent_encryption(&fi, encryption);
 
 	ret = log_extent_csums(trans, inode, log, em, ctx);
 	if (ret)
diff --git a/include/uapi/linux/btrfs_tree.h b/include/uapi/linux/btrfs_tree.h
index 50c9e01a3cb4..dee650f0082c 100644
--- a/include/uapi/linux/btrfs_tree.h
+++ b/include/uapi/linux/btrfs_tree.h
@@ -1095,8 +1095,14 @@ struct btrfs_file_extent_item {
 	 * but not for stat.
 	 */
 	__u8 compression;
+
+	/*
+	 * Type of encryption in use. Unencrypted value is 0.
+	 */
 	__u8 encryption;
-	__le16 other_encoding; /* spare for later use */
+
+	/* spare for later use */
+	__le16 other_encoding;
 
 	/* are we inline data or a real extent? */
 	__u8 type;
-- 
2.41.0

[PATCH 20/35] btrfs: add fscrypt_info and encryption_type to extent_map

[Josef Bacik]

From: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>

Each extent_map will end up with a pointer to its associated
fscrypt_info if any, which should have the same lifetime as the
extent_map. We are also going to need to track the encryption_type for
the file extent items.  Add the fscrypt_info to the extent_map, and the
subsequent code for transferring it in the split and merge cases, as
well as the code necessary to free them.  A future patch will add the
code to load them as appropriate.

Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/extent_map.c | 32 +++++++++++++++++++++++++++++---
 fs/btrfs/extent_map.h |  2 ++
 fs/btrfs/file-item.c  |  1 +
 fs/btrfs/inode.c      |  1 +
 4 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index af5ff6b10865..8c8023388758 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -61,6 +61,7 @@ struct extent_map *alloc_extent_map(void)
 
 static void __free_extent_map(struct extent_map *em)
 {
+	fscrypt_put_extent_info(em->fscrypt_info);
 	if (test_bit(EXTENT_FLAG_FS_MAPPING, &em->flags))
 		kfree(em->map_lookup);
 	kmem_cache_free(extent_map_cache, em);
@@ -103,12 +104,24 @@ void free_extent_map_safe(struct extent_map_tree *tree,
 	if (!em)
 		return;
 
-	if (refcount_dec_and_test(&em->refs)) {
-		WARN_ON(extent_map_in_tree(em));
-		WARN_ON(!list_empty(&em->list));
+	if (!refcount_dec_and_test(&em->refs))
+		return;
+
+	WARN_ON(extent_map_in_tree(em));
+	WARN_ON(!list_empty(&em->list));
+
+	/*
+	 * We could take a lock freeing the fscrypt_info, so add this to the
+	 * list of freed_extents to be freed later.
+	 */
+	if (em->fscrypt_info) {
 		list_add_tail(&em->free_list, &tree->freed_extents);
 		set_bit(EXTENT_MAP_TREE_PENDING_FREES, &tree->flags);
+		return;
 	}
+
+	/* Nothing scary here, just free the object. */
+	__free_extent_map(em);
 }
 
 /*
@@ -274,6 +287,12 @@ static int mergable_maps(struct extent_map *prev, struct extent_map *next)
 	if (!list_empty(&prev->list) || !list_empty(&next->list))
 		return 0;
 
+	/*
+	 * Don't merge adjacent encrypted maps.
+	 */
+	if (prev->fscrypt_info || next->fscrypt_info)
+		return 0;
+
 	ASSERT(next->block_start != EXTENT_MAP_DELALLOC &&
 	       prev->block_start != EXTENT_MAP_DELALLOC);
 
@@ -884,6 +903,8 @@ void btrfs_drop_extent_map_range(struct btrfs_inode *inode, u64 start, u64 end,
 			split->generation = gen;
 			split->flags = flags;
 			split->compress_type = em->compress_type;
+			split->fscrypt_info =
+				fscrypt_get_extent_info(em->fscrypt_info);
 			replace_extent_mapping(em_tree, em, split, modified);
 			free_extent_map(split);
 			split = split2;
@@ -925,6 +946,8 @@ void btrfs_drop_extent_map_range(struct btrfs_inode *inode, u64 start, u64 end,
 				split->orig_block_len = 0;
 			}
 
+			split->fscrypt_info =
+				fscrypt_get_extent_info(em->fscrypt_info);
 			if (extent_map_in_tree(em)) {
 				replace_extent_mapping(em_tree, em, split,
 						       modified);
@@ -1087,6 +1110,7 @@ int split_extent_map(struct btrfs_inode *inode, u64 start, u64 len, u64 pre,
 	split_pre->flags = flags;
 	split_pre->compress_type = em->compress_type;
 	split_pre->generation = em->generation;
+	split_pre->fscrypt_info = fscrypt_get_extent_info(em->fscrypt_info);
 
 	replace_extent_mapping(em_tree, em, split_pre, 1);
 
@@ -1106,6 +1130,8 @@ int split_extent_map(struct btrfs_inode *inode, u64 start, u64 len, u64 pre,
 	split_mid->flags = flags;
 	split_mid->compress_type = em->compress_type;
 	split_mid->generation = em->generation;
+	split_mid->fscrypt_info = fscrypt_get_extent_info(em->fscrypt_info);
+
 	add_extent_mapping(em_tree, split_mid, 1);
 
 	/* Once for us */
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index 2093720271ea..2d618e61ceb5 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -50,10 +50,12 @@ struct extent_map {
 	 */
 	u64 generation;
 	unsigned long flags;
+	struct fscrypt_extent_info *fscrypt_info;
 	/* Used for chunk mappings, flag EXTENT_FLAG_FS_MAPPING must be set */
 	struct map_lookup *map_lookup;
 	refcount_t refs;
 	unsigned int compress_type;
+	unsigned int encryption_type;
 	struct list_head list;
 	struct list_head free_list;
 };
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index 45cae356e89b..26f35c1baedc 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -1305,6 +1305,7 @@ void btrfs_extent_item_to_extent_map(struct btrfs_inode *inode,
 			if (type == BTRFS_FILE_EXTENT_PREALLOC)
 				set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
 		}
+		em->encryption_type = btrfs_file_extent_encryption(leaf, fi);
 	} else if (type == BTRFS_FILE_EXTENT_INLINE) {
 		em->block_start = EXTENT_MAP_INLINE;
 		em->start = extent_start;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index db053b392d26..d26062b67211 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -7350,6 +7350,7 @@ static struct extent_map *create_io_em(struct btrfs_inode *inode, u64 start,
 		set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
 		em->compress_type = compress_type;
 	}
+	em->encryption_type = BTRFS_ENCRYPTION_NONE;
 
 	ret = btrfs_replace_extent_map_range(inode, em, true);
 	if (ret) {
-- 
2.41.0

[PATCH 21/35] btrfs: add fscrypt_info and encryption_type to ordered_extent

[Josef Bacik]

We're going to need these to update the file extent items once the
writes are complete.  Add them and add the pieces necessary to assign
them and free everything.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/ordered-data.c | 2 ++
 fs/btrfs/ordered-data.h | 6 ++++++
 2 files changed, 8 insertions(+)

diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index b133ea0bc459..d33a780d9893 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -182,6 +182,7 @@ static struct btrfs_ordered_extent *alloc_ordered_extent(
 	entry->bytes_left = num_bytes;
 	entry->inode = igrab(&inode->vfs_inode);
 	entry->compress_type = compress_type;
+	entry->encryption_type = BTRFS_ENCRYPTION_NONE;
 	entry->truncated_len = (u64)-1;
 	entry->qgroup_rsv = ret;
 	entry->flags = flags;
@@ -568,6 +569,7 @@ void btrfs_put_ordered_extent(struct btrfs_ordered_extent *entry)
 			list_del(&sum->list);
 			kvfree(sum);
 		}
+		fscrypt_put_extent_info(entry->fscrypt_info);
 		kmem_cache_free(btrfs_ordered_extent_cache, entry);
 	}
 }
diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
index 1c51ac57e5df..607814876f1f 100644
--- a/fs/btrfs/ordered-data.h
+++ b/fs/btrfs/ordered-data.h
@@ -122,6 +122,9 @@ struct btrfs_ordered_extent {
 	/* compression algorithm */
 	int compress_type;
 
+	/* encryption mode */
+	int encryption_type;
+
 	/* Qgroup reserved space */
 	int qgroup_rsv;
 
@@ -131,6 +134,9 @@ struct btrfs_ordered_extent {
 	/* the inode we belong to */
 	struct inode *inode;
 
+	/* the fscrypt_info for this extent, if necessary */
+	struct fscrypt_extent_info *fscrypt_info;
+
 	/* list of checksums for insertion when the extent io is done */
 	struct list_head list;
 
-- 
2.41.0

[PATCH 22/35] btrfs: plumb through setting the fscrypt_info for ordered extents

[Josef Bacik]

We're going to be getting fscrypt_info from the extent maps, update the
helpers to take an fscrypt_info argument and use that to set the
encryption type on the ordered extent.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/inode.c        | 20 +++++++++++---------
 fs/btrfs/ordered-data.c | 32 ++++++++++++++++++++------------
 fs/btrfs/ordered-data.h |  9 +++++----
 3 files changed, 36 insertions(+), 25 deletions(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index d26062b67211..903ec2d460f5 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1162,7 +1162,8 @@ static void submit_one_async_extent(struct async_chunk *async_chunk,
 	}
 	free_extent_map(em);
 
-	ordered = btrfs_alloc_ordered_extent(inode, start,	/* file_offset */
+	ordered = btrfs_alloc_ordered_extent(inode, NULL,
+				       start,			/* file_offset */
 				       async_extent->ram_size,	/* num_bytes */
 				       async_extent->ram_size,	/* ram_bytes */
 				       ins.objectid,		/* disk_bytenr */
@@ -1425,9 +1426,10 @@ static noinline int cow_file_range(struct btrfs_inode *inode,
 		}
 		free_extent_map(em);
 
-		ordered = btrfs_alloc_ordered_extent(inode, start, ram_size,
-					ram_size, ins.objectid, cur_alloc_size,
-					0, 1 << BTRFS_ORDERED_REGULAR,
+		ordered = btrfs_alloc_ordered_extent(inode, NULL,
+					start, ram_size, ram_size, ins.objectid,
+					cur_alloc_size, 0,
+					1 << BTRFS_ORDERED_REGULAR,
 					BTRFS_COMPRESS_NONE);
 		if (IS_ERR(ordered)) {
 			ret = PTR_ERR(ordered);
@@ -2158,7 +2160,7 @@ static noinline int run_delalloc_nocow(struct btrfs_inode *inode,
 			free_extent_map(em);
 		}
 
-		ordered = btrfs_alloc_ordered_extent(inode, cur_offset,
+		ordered = btrfs_alloc_ordered_extent(inode, NULL, cur_offset,
 				nocow_args.num_bytes, nocow_args.num_bytes,
 				nocow_args.disk_bytenr, nocow_args.num_bytes, 0,
 				is_prealloc
@@ -7041,7 +7043,7 @@ static struct extent_map *btrfs_create_dio_extent(struct btrfs_inode *inode,
 		if (IS_ERR(em))
 			goto out;
 	}
-	ordered = btrfs_alloc_ordered_extent(inode, start, len, len,
+	ordered = btrfs_alloc_ordered_extent(inode, NULL, start, len, len,
 					     block_start, block_len, 0,
 					     (1 << type) |
 					     (1 << BTRFS_ORDERED_DIRECT),
@@ -10512,9 +10514,9 @@ ssize_t btrfs_do_encoded_write(struct kiocb *iocb, struct iov_iter *from,
 	}
 	free_extent_map(em);
 
-	ordered = btrfs_alloc_ordered_extent(inode, start, num_bytes, ram_bytes,
-				       ins.objectid, ins.offset,
-				       encoded->unencoded_offset,
+	ordered = btrfs_alloc_ordered_extent(inode, NULL, start,
+				       num_bytes, ram_bytes, ins.objectid,
+				       ins.offset, encoded->unencoded_offset,
 				       (1 << BTRFS_ORDERED_ENCODED) |
 				       (1 << BTRFS_ORDERED_COMPRESSED),
 				       compression);
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index d33a780d9893..81b0fe575011 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -147,9 +147,11 @@ static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree,
 }
 
 static struct btrfs_ordered_extent *alloc_ordered_extent(
-			struct btrfs_inode *inode, u64 file_offset, u64 num_bytes,
-			u64 ram_bytes, u64 disk_bytenr, u64 disk_num_bytes,
-			u64 offset, unsigned long flags, int compress_type)
+			struct btrfs_inode *inode,
+			struct fscrypt_extent_info *fscrypt_info,
+			u64 file_offset, u64 num_bytes, u64 ram_bytes,
+			u64 disk_bytenr, u64 disk_num_bytes, u64 offset,
+			unsigned long flags, int compress_type)
 {
 	struct btrfs_ordered_extent *entry;
 	int ret;
@@ -182,10 +184,12 @@ static struct btrfs_ordered_extent *alloc_ordered_extent(
 	entry->bytes_left = num_bytes;
 	entry->inode = igrab(&inode->vfs_inode);
 	entry->compress_type = compress_type;
-	entry->encryption_type = BTRFS_ENCRYPTION_NONE;
 	entry->truncated_len = (u64)-1;
 	entry->qgroup_rsv = ret;
 	entry->flags = flags;
+	entry->fscrypt_info = fscrypt_get_extent_info(fscrypt_info);
+	entry->encryption_type = entry->fscrypt_info ?
+		BTRFS_ENCRYPTION_FSCRYPT : BTRFS_ENCRYPTION_NONE;
 	refcount_set(&entry->refs, 1);
 	init_waitqueue_head(&entry->wait);
 	INIT_LIST_HEAD(&entry->list);
@@ -248,6 +252,7 @@ static void insert_ordered_extent(struct btrfs_ordered_extent *entry)
  * Add an ordered extent to the per-inode tree.
  *
  * @inode:           Inode that this extent is for.
+ * @fscrypt_info:    The fscrypt_extent_info for this extent, if necessary.
  * @file_offset:     Logical offset in file where the extent starts.
  * @num_bytes:       Logical length of extent in file.
  * @ram_bytes:       Full length of unencoded data.
@@ -264,17 +269,19 @@ static void insert_ordered_extent(struct btrfs_ordered_extent *entry)
  * Return: the new ordered extent or error pointer.
  */
 struct btrfs_ordered_extent *btrfs_alloc_ordered_extent(
-			struct btrfs_inode *inode, u64 file_offset,
-			u64 num_bytes, u64 ram_bytes, u64 disk_bytenr,
-			u64 disk_num_bytes, u64 offset, unsigned long flags,
-			int compress_type)
+			struct btrfs_inode *inode,
+			struct fscrypt_extent_info *fscrypt_info,
+			u64 file_offset, u64 num_bytes, u64 ram_bytes,
+			u64 disk_bytenr, u64 disk_num_bytes, u64 offset,
+			unsigned long flags, int compress_type)
 {
 	struct btrfs_ordered_extent *entry;
 
 	ASSERT((flags & ~BTRFS_ORDERED_TYPE_FLAGS) == 0);
 
-	entry = alloc_ordered_extent(inode, file_offset, num_bytes, ram_bytes,
-				     disk_bytenr, disk_num_bytes, offset, flags,
+	entry = alloc_ordered_extent(inode, fscrypt_info, file_offset,
+				     num_bytes, ram_bytes, disk_bytenr,
+				     disk_num_bytes, offset, flags,
 				     compress_type);
 	if (!IS_ERR(entry))
 		insert_ordered_extent(entry);
@@ -1181,8 +1188,9 @@ struct btrfs_ordered_extent *btrfs_split_ordered_extent(
 	if (WARN_ON_ONCE(ordered->disk_num_bytes != ordered->num_bytes))
 		return ERR_PTR(-EINVAL);
 
-	new = alloc_ordered_extent(inode, file_offset, len, len, disk_bytenr,
-				   len, 0, flags, ordered->compress_type);
+	new = alloc_ordered_extent(inode, ordered->fscrypt_info, file_offset,
+				   len, len, disk_bytenr, len, 0, flags,
+				   ordered->compress_type);
 	if (IS_ERR(new))
 		return new;
 
diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
index 607814876f1f..e19e62d5171a 100644
--- a/fs/btrfs/ordered-data.h
+++ b/fs/btrfs/ordered-data.h
@@ -185,10 +185,11 @@ bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode,
 				    struct btrfs_ordered_extent **cached,
 				    u64 file_offset, u64 io_size);
 struct btrfs_ordered_extent *btrfs_alloc_ordered_extent(
-			struct btrfs_inode *inode, u64 file_offset,
-			u64 num_bytes, u64 ram_bytes, u64 disk_bytenr,
-			u64 disk_num_bytes, u64 offset, unsigned long flags,
-			int compress_type);
+			struct btrfs_inode *inode,
+			struct fscrypt_extent_info *fscrypt_info,
+			u64 file_offset, u64 num_bytes, u64 ram_bytes,
+			u64 disk_bytenr, u64 disk_num_bytes, u64 offset,
+			unsigned long flags, int compress_type);
 void btrfs_add_ordered_sum(struct btrfs_ordered_extent *entry,
 			   struct btrfs_ordered_sum *sum);
 struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *inode,
-- 
2.41.0

[PATCH 23/35] btrfs: populate the ordered_extent with the fscrypt context

[Josef Bacik]

The fscrypt_extent_info will be tied to the extent_map lifetime, so it
will be created when we create the IO em, or it'll already exist in the
NOCOW case.  Use this fscrypt_info when creating the ordered extent to
make sure everything is passed through properly.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/inode.c | 62 +++++++++++++++++++++++++++++++++---------------
 1 file changed, 43 insertions(+), 19 deletions(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 903ec2d460f5..19831291fb54 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1160,9 +1160,8 @@ static void submit_one_async_extent(struct async_chunk *async_chunk,
 		ret = PTR_ERR(em);
 		goto out_free_reserve;
 	}
-	free_extent_map(em);
 
-	ordered = btrfs_alloc_ordered_extent(inode, NULL,
+	ordered = btrfs_alloc_ordered_extent(inode, em->fscrypt_info,
 				       start,			/* file_offset */
 				       async_extent->ram_size,	/* num_bytes */
 				       async_extent->ram_size,	/* ram_bytes */
@@ -1171,6 +1170,7 @@ static void submit_one_async_extent(struct async_chunk *async_chunk,
 				       0,			/* offset */
 				       1 << BTRFS_ORDERED_COMPRESSED,
 				       async_extent->compress_type);
+	free_extent_map(em);
 	if (IS_ERR(ordered)) {
 		btrfs_drop_extent_map_range(inode, start, end, false);
 		ret = PTR_ERR(ordered);
@@ -1424,13 +1424,13 @@ static noinline int cow_file_range(struct btrfs_inode *inode,
 			ret = PTR_ERR(em);
 			goto out_reserve;
 		}
-		free_extent_map(em);
 
-		ordered = btrfs_alloc_ordered_extent(inode, NULL,
+		ordered = btrfs_alloc_ordered_extent(inode, em->fscrypt_info,
 					start, ram_size, ram_size, ins.objectid,
 					cur_alloc_size, 0,
 					1 << BTRFS_ORDERED_REGULAR,
 					BTRFS_COMPRESS_NONE);
+		free_extent_map(em);
 		if (IS_ERR(ordered)) {
 			ret = PTR_ERR(ordered);
 			goto out_drop_extent_cache;
@@ -2003,6 +2003,8 @@ static noinline int run_delalloc_nocow(struct btrfs_inode *inode,
 		struct btrfs_key found_key;
 		struct btrfs_file_extent_item *fi;
 		struct extent_buffer *leaf;
+		struct extent_map *em = NULL;
+		struct fscrypt_extent_info *fscrypt_info = NULL;
 		u64 extent_end;
 		u64 ram_bytes;
 		u64 nocow_end;
@@ -2143,7 +2145,6 @@ static noinline int run_delalloc_nocow(struct btrfs_inode *inode,
 		is_prealloc = extent_type == BTRFS_FILE_EXTENT_PREALLOC;
 		if (is_prealloc) {
 			u64 orig_start = found_key.offset - nocow_args.extent_offset;
-			struct extent_map *em;
 
 			em = create_io_em(inode, cur_offset, nocow_args.num_bytes,
 					  orig_start,
@@ -2157,16 +2158,32 @@ static noinline int run_delalloc_nocow(struct btrfs_inode *inode,
 				ret = PTR_ERR(em);
 				goto error;
 			}
-			free_extent_map(em);
+			fscrypt_info = em->fscrypt_info;
+		} else if (IS_ENCRYPTED(&inode->vfs_inode)) {
+			/*
+			 * We only want to do this lookup if we're encrypted,
+			 * otherwise fsrypt_info will be null and we can avoid
+			 * this lookup.
+			 */
+			em = btrfs_get_extent(inode, NULL, 0, cur_offset,
+					      nocow_args.num_bytes);
+			if (IS_ERR(em)) {
+				btrfs_dec_nocow_writers(nocow_bg);
+				ret = PTR_ERR(em);
+				goto error;
+			}
+			fscrypt_info = em->fscrypt_info;
 		}
 
-		ordered = btrfs_alloc_ordered_extent(inode, NULL, cur_offset,
-				nocow_args.num_bytes, nocow_args.num_bytes,
-				nocow_args.disk_bytenr, nocow_args.num_bytes, 0,
+		ordered = btrfs_alloc_ordered_extent(inode, fscrypt_info,
+				cur_offset, nocow_args.num_bytes,
+				nocow_args.num_bytes, nocow_args.disk_bytenr,
+				nocow_args.num_bytes, 0,
 				is_prealloc
 				? (1 << BTRFS_ORDERED_PREALLOC)
 				: (1 << BTRFS_ORDERED_NOCOW),
 				BTRFS_COMPRESS_NONE);
+		free_extent_map(em);
 		btrfs_dec_nocow_writers(nocow_bg);
 		if (IS_ERR(ordered)) {
 			if (is_prealloc) {
@@ -7023,6 +7040,7 @@ struct extent_map *btrfs_get_extent(struct btrfs_inode *inode,
 
 static struct extent_map *btrfs_create_dio_extent(struct btrfs_inode *inode,
 						  struct btrfs_dio_data *dio_data,
+						  struct extent_map *orig_em,
 						  const u64 start,
 						  const u64 len,
 						  const u64 orig_start,
@@ -7034,6 +7052,7 @@ static struct extent_map *btrfs_create_dio_extent(struct btrfs_inode *inode,
 {
 	struct extent_map *em = NULL;
 	struct btrfs_ordered_extent *ordered;
+	struct fscrypt_extent_info *fscrypt_info = NULL;
 
 	if (type != BTRFS_ORDERED_NOCOW) {
 		em = create_io_em(inode, start, len, orig_start, block_start,
@@ -7042,9 +7061,13 @@ static struct extent_map *btrfs_create_dio_extent(struct btrfs_inode *inode,
 				  type);
 		if (IS_ERR(em))
 			goto out;
+		fscrypt_info = em->fscrypt_info;
+	} else {
+		fscrypt_info = orig_em->fscrypt_info;
 	}
-	ordered = btrfs_alloc_ordered_extent(inode, NULL, start, len, len,
-					     block_start, block_len, 0,
+
+	ordered = btrfs_alloc_ordered_extent(inode, fscrypt_info, start, len,
+					     len, block_start, block_len, 0,
 					     (1 << type) |
 					     (1 << BTRFS_ORDERED_DIRECT),
 					     BTRFS_COMPRESS_NONE);
@@ -7081,9 +7104,10 @@ static struct extent_map *btrfs_new_extent_direct(struct btrfs_inode *inode,
 	if (ret)
 		return ERR_PTR(ret);
 
-	em = btrfs_create_dio_extent(inode, dio_data, start, ins.offset, start,
-				     ins.objectid, ins.offset, ins.offset,
-				     ins.offset, BTRFS_ORDERED_REGULAR);
+	em = btrfs_create_dio_extent(inode, dio_data, NULL, start, ins.offset,
+				     start, ins.objectid, ins.offset,
+				     ins.offset, ins.offset,
+				     BTRFS_ORDERED_REGULAR);
 	btrfs_dec_block_group_reservations(fs_info, ins.objectid);
 	if (IS_ERR(em))
 		btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset,
@@ -7428,9 +7452,9 @@ static int btrfs_get_blocks_direct_write(struct extent_map **map,
 		}
 		space_reserved = true;
 
-		em2 = btrfs_create_dio_extent(BTRFS_I(inode), dio_data, start, len,
-					      orig_start, block_start,
-					      len, orig_block_len,
+		em2 = btrfs_create_dio_extent(BTRFS_I(inode), dio_data, em,
+					      start, len, orig_start,
+					      block_start, len, orig_block_len,
 					      ram_bytes, type);
 		btrfs_dec_nocow_writers(bg);
 		if (type == BTRFS_ORDERED_PREALLOC) {
@@ -10512,14 +10536,14 @@ ssize_t btrfs_do_encoded_write(struct kiocb *iocb, struct iov_iter *from,
 		ret = PTR_ERR(em);
 		goto out_free_reserved;
 	}
-	free_extent_map(em);
 
-	ordered = btrfs_alloc_ordered_extent(inode, NULL, start,
+	ordered = btrfs_alloc_ordered_extent(inode, em->fscrypt_info, start,
 				       num_bytes, ram_bytes, ins.objectid,
 				       ins.offset, encoded->unencoded_offset,
 				       (1 << BTRFS_ORDERED_ENCODED) |
 				       (1 << BTRFS_ORDERED_COMPRESSED),
 				       compression);
+	free_extent_map(em);
 	if (IS_ERR(ordered)) {
 		btrfs_drop_extent_map_range(inode, start, end, false);
 		ret = PTR_ERR(ordered);
-- 
2.41.0

[PATCH 24/35] btrfs: keep track of fscrypt info and orig_start for dio reads

[Josef Bacik]

We keep track of this information in the ordered extent for writes, but
we need it for reads as well.  Add fscrypt_extent_info and orig_start to
the dio_data so we can populate this on reads.  This will be used later
when we attach the fscrypt context to the bios.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/inode.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 19831291fb54..89cb09a40f58 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -83,6 +83,8 @@ struct btrfs_dio_data {
 	ssize_t submitted;
 	struct extent_changeset *data_reserved;
 	struct btrfs_ordered_extent *ordered;
+	struct fscrypt_extent_info *fscrypt_info;
+	u64 orig_start;
 	bool data_space_reserved;
 	bool nocow_done;
 };
@@ -7729,6 +7731,10 @@ static int btrfs_dio_iomap_begin(struct inode *inode, loff_t start,
 							       release_len);
 		}
 	} else {
+		dio_data->fscrypt_info =
+			fscrypt_get_extent_info(em->fscrypt_info);
+		dio_data->orig_start = em->orig_start;
+
 		/*
 		 * We need to unlock only the end area that we aren't using.
 		 * The rest is going to be unlocked by the endio routine.
@@ -7810,6 +7816,11 @@ static int btrfs_dio_iomap_end(struct inode *inode, loff_t pos, loff_t length,
 		dio_data->ordered = NULL;
 	}
 
+	if (dio_data->fscrypt_info) {
+		fscrypt_put_extent_info(dio_data->fscrypt_info);
+		dio_data->fscrypt_info = NULL;
+	}
+
 	if (write)
 		extent_changeset_free(dio_data->data_reserved);
 	return ret;
-- 
2.41.0

[PATCH 25/35] btrfs: add an optional encryption context to the end of file extents

[Josef Bacik]

The fscrypt encryption context can be extended to include different
things in the future.  To facilitate future expansion add an optional
btrfs_encryption_info to the end of the file extent.  This will hold the
size of the context and then will have the binary context tacked onto
the end of the extent item.

Add the appropriate accessors to make it easy to read this information
if we have encryption set, and then update the tree-checker to validate
that if this is indeed set properly that the size matches properly.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/accessors.h            | 48 +++++++++++++++++++++++++++
 fs/btrfs/tree-checker.c         | 58 ++++++++++++++++++++++++++++-----
 include/uapi/linux/btrfs_tree.h | 17 +++++++++-
 3 files changed, 113 insertions(+), 10 deletions(-)

diff --git a/fs/btrfs/accessors.h b/fs/btrfs/accessors.h
index 5627f13a3d3e..3e6c81449ce7 100644
--- a/fs/btrfs/accessors.h
+++ b/fs/btrfs/accessors.h
@@ -934,6 +934,10 @@ BTRFS_SETGET_STACK_FUNCS(super_uuid_tree_generation, struct btrfs_super_block,
 BTRFS_SETGET_STACK_FUNCS(super_nr_global_roots, struct btrfs_super_block,
 			 nr_global_roots, 64);
 
+/* struct btrfs_file_extent_encryption_info */
+BTRFS_SETGET_FUNCS(encryption_info_size, struct btrfs_encryption_info, size,
+		   32);
+
 /* struct btrfs_file_extent_item */
 BTRFS_SETGET_STACK_FUNCS(stack_file_extent_type, struct btrfs_file_extent_item,
 			 type, 8);
@@ -975,6 +979,50 @@ BTRFS_SETGET_FUNCS(file_extent_encryption, struct btrfs_file_extent_item,
 BTRFS_SETGET_FUNCS(file_extent_other_encoding, struct btrfs_file_extent_item,
 		   other_encoding, 16);
 
+static inline struct btrfs_encryption_info *btrfs_file_extent_encryption_info(
+					const struct btrfs_file_extent_item *ei)
+{
+	unsigned long offset = (unsigned long)ei;
+
+	offset += offsetof(struct btrfs_file_extent_item, encryption_info);
+	return (struct btrfs_encryption_info *)offset;
+}
+
+static inline unsigned long btrfs_file_extent_encryption_ctx_offset(
+					const struct btrfs_file_extent_item *ei)
+{
+	unsigned long offset = (unsigned long)ei;
+
+	offset += offsetof(struct btrfs_file_extent_item, encryption_info);
+	return offset + offsetof(struct btrfs_encryption_info, context);
+}
+
+static inline u32 btrfs_file_extent_encryption_ctx_size(
+					const struct extent_buffer *eb,
+					const struct btrfs_file_extent_item *ei)
+{
+	return btrfs_encryption_info_size(eb,
+					  btrfs_file_extent_encryption_info(ei));
+}
+
+static inline void btrfs_set_file_extent_encryption_ctx_size(
+						const struct extent_buffer *eb,
+						struct btrfs_file_extent_item *ei,
+						u32 val)
+{
+	btrfs_set_encryption_info_size(eb,
+				       btrfs_file_extent_encryption_info(ei),
+				       val);
+}
+
+static inline u32 btrfs_file_extent_encryption_info_size(
+					const struct extent_buffer *eb,
+					const struct btrfs_file_extent_item *ei)
+{
+	return btrfs_encryption_info_size(eb,
+					  btrfs_file_extent_encryption_info(ei));
+}
+
 /* btrfs_qgroup_status_item */
 BTRFS_SETGET_FUNCS(qgroup_status_generation, struct btrfs_qgroup_status_item,
 		   generation, 64);
diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c
index c2afdf65c2bf..7fe6210c243a 100644
--- a/fs/btrfs/tree-checker.c
+++ b/fs/btrfs/tree-checker.c
@@ -211,6 +211,7 @@ static int check_extent_data_item(struct extent_buffer *leaf,
 	u32 item_size = btrfs_item_size(leaf, slot);
 	u64 extent_end;
 	u8 policy;
+	u8 fe_type;
 
 	if (unlikely(!IS_ALIGNED(key->offset, sectorsize))) {
 		file_extent_err(leaf, slot,
@@ -241,12 +242,12 @@ static int check_extent_data_item(struct extent_buffer *leaf,
 				SZ_4K);
 		return -EUCLEAN;
 	}
-	if (unlikely(btrfs_file_extent_type(leaf, fi) >=
-		     BTRFS_NR_FILE_EXTENT_TYPES)) {
+
+	fe_type = btrfs_file_extent_type(leaf, fi);
+	if (unlikely(fe_type >= BTRFS_NR_FILE_EXTENT_TYPES)) {
 		file_extent_err(leaf, slot,
 		"invalid type for file extent, have %u expect range [0, %u]",
-			btrfs_file_extent_type(leaf, fi),
-			BTRFS_NR_FILE_EXTENT_TYPES - 1);
+			fe_type, BTRFS_NR_FILE_EXTENT_TYPES - 1);
 		return -EUCLEAN;
 	}
 
@@ -295,12 +296,51 @@ static int check_extent_data_item(struct extent_buffer *leaf,
 		return 0;
 	}
 
-	/* Regular or preallocated extent has fixed item size */
-	if (unlikely(item_size != sizeof(*fi))) {
-		file_extent_err(leaf, slot,
+	if (policy == BTRFS_ENCRYPTION_FSCRYPT) {
+		size_t fe_size = sizeof(*fi) +
+			sizeof(struct btrfs_encryption_info);
+		u32 ctxsize;
+
+		if (unlikely(item_size < fe_size)) {
+			file_extent_err(leaf, slot,
+	"invalid item size for encrypted file extent, have %u expect = %zu + size of u32",
+					item_size, sizeof(*fi));
+			return -EUCLEAN;
+		}
+
+		ctxsize = btrfs_file_extent_encryption_info_size(leaf, fi);
+		if (unlikely(item_size != (fe_size + ctxsize))) {
+			file_extent_err(leaf, slot,
+	"invalid item size for encrypted file extent, have %u expect = %zu + context of size %u",
+					item_size, fe_size, ctxsize);
+			return -EUCLEAN;
+		}
+
+		if (unlikely(ctxsize > BTRFS_MAX_EXTENT_CTX_SIZE)) {
+			file_extent_err(leaf, slot,
+	"invalid file extent context size, have %u expect a maximum of %u",
+					ctxsize, BTRFS_MAX_EXTENT_CTX_SIZE);
+			return -EUCLEAN;
+		}
+
+		/*
+		 * Only regular and prealloc extents should have an encryption
+		 * context.
+		 */
+		if (unlikely(fe_type != BTRFS_FILE_EXTENT_REG &&
+			     fe_type != BTRFS_FILE_EXTENT_PREALLOC)) {
+			file_extent_err(leaf, slot,
+		"invalid type for encrypted file extent, have %u",
+					btrfs_file_extent_type(leaf, fi));
+			return -EUCLEAN;
+		}
+	} else {
+		if (unlikely(item_size != sizeof(*fi))) {
+			file_extent_err(leaf, slot,
 	"invalid item size for reg/prealloc file extent, have %u expect %zu",
-			item_size, sizeof(*fi));
-		return -EUCLEAN;
+					item_size, sizeof(*fi));
+			return -EUCLEAN;
+		}
 	}
 	if (unlikely(CHECK_FE_ALIGNED(leaf, slot, fi, ram_bytes, sectorsize) ||
 		     CHECK_FE_ALIGNED(leaf, slot, fi, disk_bytenr, sectorsize) ||
diff --git a/include/uapi/linux/btrfs_tree.h b/include/uapi/linux/btrfs_tree.h
index dee650f0082c..5d9563fb6e7f 100644
--- a/include/uapi/linux/btrfs_tree.h
+++ b/include/uapi/linux/btrfs_tree.h
@@ -1067,12 +1067,24 @@ enum {
 	BTRFS_NR_FILE_EXTENT_TYPES = 3,
 };
 
+/*
+ * Currently just the FSCRYPT_SET_CONTEXT_MAX_SIZE, which is larger than the
+ * current extent context size from fscrypt, so this should give us plenty of
+ * breathing room for expansion later.
+ */
+#define BTRFS_MAX_EXTENT_CTX_SIZE 40
+
 enum {
 	BTRFS_ENCRYPTION_NONE,
 	BTRFS_ENCRYPTION_FSCRYPT,
 	BTRFS_NR_ENCRYPTION_TYPES,
 };
 
+struct btrfs_encryption_info {
+	__le32 size;
+	__u8 context[0];
+};
+
 struct btrfs_file_extent_item {
 	/*
 	 * transaction id that created this extent
@@ -1128,7 +1140,10 @@ struct btrfs_file_extent_item {
 	 * always reflects the size uncompressed and without encoding.
 	 */
 	__le64 num_bytes;
-
+	/*
+	 * the encryption info, if any
+	 */
+	struct btrfs_encryption_info encryption_info[0];
 } __attribute__ ((__packed__));
 
 struct btrfs_csum_item {
-- 
2.41.0

[PATCH 26/35] btrfs: explicitly track file extent length for replace and drop

[Josef Bacik]

From: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>

With the advent of storing fscrypt contexts with each encrypted extent,
extents will have a variable length depending on encryption status.
Make sure the replace and drop file extent item helpers encode this
information so that everything gets updated properly.

Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/ctree.h    | 2 ++
 fs/btrfs/file.c     | 4 ++--
 fs/btrfs/inode.c    | 7 +++++--
 fs/btrfs/reflink.c  | 1 +
 fs/btrfs/tree-log.c | 5 +++--
 5 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 2758fbae7e39..5b0cccdab92a 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -339,6 +339,8 @@ struct btrfs_replace_extent_info {
 	u64 file_offset;
 	/* Pointer to a file extent item of type regular or prealloc. */
 	char *extent_buf;
+	/* The length of @extent_buf */
+	u32 extent_buf_size;
 	/*
 	 * Set to true when attempting to replace a file range with a new extent
 	 * described by this structure, set to false when attempting to clone an
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 8dcc5ae9c9e1..70a801b90d13 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -2262,14 +2262,14 @@ static int btrfs_insert_replace_extent(struct btrfs_trans_handle *trans,
 	key.type = BTRFS_EXTENT_DATA_KEY;
 	key.offset = extent_info->file_offset;
 	ret = btrfs_insert_empty_item(trans, root, path, &key,
-				      sizeof(struct btrfs_file_extent_item));
+				      extent_info->extent_buf_size);
 	if (ret)
 		return ret;
 	leaf = path->nodes[0];
 	slot = path->slots[0];
 	write_extent_buffer(leaf, extent_info->extent_buf,
 			    btrfs_item_ptr_offset(leaf, slot),
-			    sizeof(struct btrfs_file_extent_item));
+			    extent_info->extent_buf_size);
 	extent = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
 	ASSERT(btrfs_file_extent_type(leaf, extent) != BTRFS_FILE_EXTENT_INLINE);
 	btrfs_set_file_extent_offset(leaf, extent, extent_info->data_offset);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 89cb09a40f58..6a835967684d 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2899,6 +2899,7 @@ static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
 	u64 num_bytes = btrfs_stack_file_extent_num_bytes(stack_fi);
 	u64 ram_bytes = btrfs_stack_file_extent_ram_bytes(stack_fi);
 	struct btrfs_drop_extents_args drop_args = { 0 };
+	size_t fscrypt_context_size = 0;
 	int ret;
 
 	path = btrfs_alloc_path();
@@ -2918,7 +2919,7 @@ static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
 	drop_args.start = file_pos;
 	drop_args.end = file_pos + num_bytes;
 	drop_args.replace_extent = true;
-	drop_args.extent_item_size = sizeof(*stack_fi);
+	drop_args.extent_item_size = sizeof(*stack_fi) + fscrypt_context_size;
 	ret = btrfs_drop_extents(trans, root, inode, &drop_args);
 	if (ret)
 		goto out;
@@ -2929,7 +2930,7 @@ static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
 		ins.type = BTRFS_EXTENT_DATA_KEY;
 
 		ret = btrfs_insert_empty_item(trans, root, path, &ins,
-					      sizeof(*stack_fi));
+					      sizeof(*stack_fi) + fscrypt_context_size);
 		if (ret)
 			goto out;
 	}
@@ -9671,6 +9672,7 @@ static struct btrfs_trans_handle *insert_prealloc_file_extent(
 	u64 len = ins->offset;
 	int qgroup_released;
 	int ret;
+	size_t fscrypt_context_size = 0;
 
 	memset(&stack_fi, 0, sizeof(stack_fi));
 
@@ -9703,6 +9705,7 @@ static struct btrfs_trans_handle *insert_prealloc_file_extent(
 	extent_info.data_len = len;
 	extent_info.file_offset = file_offset;
 	extent_info.extent_buf = (char *)&stack_fi;
+	extent_info.extent_buf_size = sizeof(stack_fi) + fscrypt_context_size;
 	extent_info.is_new_extent = true;
 	extent_info.update_times = true;
 	extent_info.qgroup_reserved = qgroup_released;
diff --git a/fs/btrfs/reflink.c b/fs/btrfs/reflink.c
index 3c66630d87ee..f5440ae447a4 100644
--- a/fs/btrfs/reflink.c
+++ b/fs/btrfs/reflink.c
@@ -500,6 +500,7 @@ static int btrfs_clone(struct inode *src, struct inode *inode,
 			clone_info.data_len = datal;
 			clone_info.file_offset = new_key.offset;
 			clone_info.extent_buf = buf;
+			clone_info.extent_buf_size = size;
 			clone_info.is_new_extent = false;
 			clone_info.update_times = !no_time_update;
 			ret = btrfs_replace_file_extents(BTRFS_I(inode), path,
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index f6f45a0f1b1e..d659547c9900 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -4630,6 +4630,7 @@ static int log_one_extent(struct btrfs_trans_handle *trans,
 	u64 extent_offset = em->start - em->orig_start;
 	u64 block_len;
 	int ret;
+	size_t fscrypt_context_size = 0;
 	u8 encryption = BTRFS_ENCRYPTION_NONE;
 
 	btrfs_set_stack_file_extent_generation(&fi, trans->transid);
@@ -4672,7 +4673,7 @@ static int log_one_extent(struct btrfs_trans_handle *trans,
 		drop_args.start = em->start;
 		drop_args.end = em->start + em->len;
 		drop_args.replace_extent = true;
-		drop_args.extent_item_size = sizeof(fi);
+		drop_args.extent_item_size = sizeof(fi) + fscrypt_context_size;
 		ret = btrfs_drop_extents(trans, log, inode, &drop_args);
 		if (ret)
 			return ret;
@@ -4684,7 +4685,7 @@ static int log_one_extent(struct btrfs_trans_handle *trans,
 		key.offset = em->start;
 
 		ret = btrfs_insert_empty_item(trans, log, path, &key,
-					      sizeof(fi));
+					      sizeof(fi) + fscrypt_context_size);
 		if (ret)
 			return ret;
 	}
-- 
2.41.0

[PATCH 27/35] btrfs: pass through fscrypt_extent_info to the file extent helpers

[Josef Bacik]

Now that we have the fscrypt_extnet_info in all of the supporting
structures, pass this through and set the file extent encryption bit
accordingly from the supporting structures.  In subsequent patches code
will be added to populate these appropriately.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/inode.c    | 18 +++++++++++-------
 fs/btrfs/tree-log.c |  2 +-
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 6a835967684d..fdb7c9e1c210 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2883,7 +2883,9 @@ int btrfs_writepage_cow_fixup(struct page *page)
 }
 
 static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
-				       struct btrfs_inode *inode, u64 file_pos,
+				       struct btrfs_inode *inode,
+				       struct fscrypt_extent_info *fscrypt_info,
+				       u64 file_pos,
 				       struct btrfs_file_extent_item *stack_fi,
 				       const bool update_inode_bytes,
 				       u64 qgroup_reserved)
@@ -3015,8 +3017,7 @@ static int insert_ordered_extent_file_extent(struct btrfs_trans_handle *trans,
 	btrfs_set_stack_file_extent_num_bytes(&stack_fi, num_bytes);
 	btrfs_set_stack_file_extent_ram_bytes(&stack_fi, ram_bytes);
 	btrfs_set_stack_file_extent_compression(&stack_fi, oe->compress_type);
-	btrfs_set_stack_file_extent_encryption(&stack_fi,
-					       BTRFS_ENCRYPTION_NONE);
+	btrfs_set_stack_file_extent_encryption(&stack_fi, oe->encryption_type);
 	/* Other encoding is reserved and always 0 */
 
 	/*
@@ -3030,8 +3031,9 @@ static int insert_ordered_extent_file_extent(struct btrfs_trans_handle *trans,
 			     test_bit(BTRFS_ORDERED_TRUNCATED, &oe->flags);
 
 	return insert_reserved_file_extent(trans, BTRFS_I(oe->inode),
-					   oe->file_offset, &stack_fi,
-					   update_inode_bytes, oe->qgroup_rsv);
+					   oe->fscrypt_info, oe->file_offset,
+					   &stack_fi, update_inode_bytes,
+					   oe->qgroup_rsv);
 }
 
 /*
@@ -9662,6 +9664,7 @@ static struct btrfs_trans_handle *insert_prealloc_file_extent(
 				       struct btrfs_trans_handle *trans_in,
 				       struct btrfs_inode *inode,
 				       struct btrfs_key *ins,
+				       struct fscrypt_extent_info *fscrypt_info,
 				       u64 file_offset)
 {
 	struct btrfs_file_extent_item stack_fi;
@@ -9683,6 +9686,7 @@ static struct btrfs_trans_handle *insert_prealloc_file_extent(
 	btrfs_set_stack_file_extent_ram_bytes(&stack_fi, len);
 	btrfs_set_stack_file_extent_compression(&stack_fi, BTRFS_COMPRESS_NONE);
 	btrfs_set_stack_file_extent_encryption(&stack_fi,
+					       fscrypt_info ? BTRFS_ENCRYPTION_FSCRYPT :
 					       BTRFS_ENCRYPTION_NONE);
 	/* Other encoding is reserved and always 0 */
 
@@ -9691,7 +9695,7 @@ static struct btrfs_trans_handle *insert_prealloc_file_extent(
 		return ERR_PTR(qgroup_released);
 
 	if (trans) {
-		ret = insert_reserved_file_extent(trans, inode,
+		ret = insert_reserved_file_extent(trans, inode, fscrypt_info,
 						  file_offset, &stack_fi,
 						  true, qgroup_released);
 		if (ret)
@@ -9785,7 +9789,7 @@ static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
 
 		last_alloc = ins.offset;
 		trans = insert_prealloc_file_extent(trans, BTRFS_I(inode),
-						    &ins, cur_offset);
+						    &ins, NULL, cur_offset);
 		/*
 		 * Now that we inserted the prealloc extent we can finally
 		 * decrement the number of reservations in the block group.
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index d659547c9900..40dd5c652f0e 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -4631,7 +4631,7 @@ static int log_one_extent(struct btrfs_trans_handle *trans,
 	u64 block_len;
 	int ret;
 	size_t fscrypt_context_size = 0;
-	u8 encryption = BTRFS_ENCRYPTION_NONE;
+	u8 encryption = em->encryption_type;
 
 	btrfs_set_stack_file_extent_generation(&fi, trans->transid);
 	if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
-- 
2.41.0

[PATCH 28/35] btrfs: pass the fscrypt_info through the replace extent infrastructure

[Josef Bacik]

Prealloc uses the btrfs_replace_file_extents() infrastructure to insert
its new extents.  We need to set the fscrypt context on these extents,
so pass this through the btrfs_replace_extent_info so it can be used in
a later patch when we hook in this infrastructure.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/ctree.h | 2 ++
 fs/btrfs/inode.c | 1 +
 2 files changed, 3 insertions(+)

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 5b0cccdab92a..b4437c1a9f22 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -341,6 +341,8 @@ struct btrfs_replace_extent_info {
 	char *extent_buf;
 	/* The length of @extent_buf */
 	u32 extent_buf_size;
+	/* The fscrypt_extent_info for a new extent. */
+	struct fscrypt_extent_info *fscrypt_info;
 	/*
 	 * Set to true when attempting to replace a file range with a new extent
 	 * described by this structure, set to false when attempting to clone an
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index fdb7c9e1c210..ee1ac2718ce3 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -9714,6 +9714,7 @@ static struct btrfs_trans_handle *insert_prealloc_file_extent(
 	extent_info.update_times = true;
 	extent_info.qgroup_reserved = qgroup_released;
 	extent_info.insertions = 0;
+	extent_info.fscrypt_info = fscrypt_info;
 
 	path = btrfs_alloc_path();
 	if (!path) {
-- 
2.41.0

[PATCH 29/35] btrfs: implement the fscrypt extent encryption hooks

[Josef Bacik]

This patch implements the necessary hooks from fscrypt to support
per-extent encryption.  There's two main entry points

btrfs_fscrypt_load_extent_info
btrfs_fscrypt_save_extent_info

btrfs_fscrypt_load_extent_info gets called when we create the extent
maps from the file extent item at btrfs_get_extent() time.  We read the
extent context, and pass it into fscrypt to create the appropriate
fscrypt_extent_info structure.  This is then used on the bio's to make
sure the encryption is done properly.

btrfs_fscrypt_save_extent_info is used to generate the fscrypt context
from fscrypt and save it into the file extent item when we create a new
file extent item.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/defrag.c    | 10 ++++++++-
 fs/btrfs/file-item.c | 11 +++++++++-
 fs/btrfs/file-item.h |  5 ++++-
 fs/btrfs/file.c      |  9 +++++++++
 fs/btrfs/fscrypt.c   | 48 ++++++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/fscrypt.h   | 31 ++++++++++++++++++++++++++++
 fs/btrfs/inode.c     | 22 +++++++++++++++++++-
 fs/btrfs/tree-log.c  | 10 +++++++++
 8 files changed, 142 insertions(+), 4 deletions(-)

diff --git a/fs/btrfs/defrag.c b/fs/btrfs/defrag.c
index dde70f358d6f..ec438961eedb 100644
--- a/fs/btrfs/defrag.c
+++ b/fs/btrfs/defrag.c
@@ -16,6 +16,7 @@
 #include "defrag.h"
 #include "file-item.h"
 #include "super.h"
+#include "fscrypt.h"
 
 static struct kmem_cache *btrfs_inode_defrag_cachep;
 
@@ -526,9 +527,12 @@ static struct extent_map *defrag_get_extent(struct btrfs_inode *inode,
 	struct btrfs_path path = { 0 };
 	struct extent_map *em;
 	struct btrfs_key key;
+	struct btrfs_fscrypt_ctx ctx;
 	u64 ino = btrfs_ino(inode);
 	int ret;
 
+	ctx.size = 0;
+
 	em = alloc_extent_map();
 	if (!em) {
 		ret = -ENOMEM;
@@ -623,7 +627,7 @@ static struct extent_map *defrag_get_extent(struct btrfs_inode *inode,
 			goto next;
 
 		/* Now this extent covers @start, convert it to em */
-		btrfs_extent_item_to_extent_map(inode, &path, fi, em);
+		btrfs_extent_item_to_extent_map(inode, &path, fi, em, &ctx);
 		break;
 next:
 		ret = btrfs_next_item(root, &path);
@@ -633,6 +637,10 @@ static struct extent_map *defrag_get_extent(struct btrfs_inode *inode,
 			goto not_found;
 	}
 	btrfs_release_path(&path);
+
+	ret = btrfs_fscrypt_load_extent_info(inode, em, &ctx);
+	if (ret)
+		goto err;
 	return em;
 
 not_found:
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index 26f35c1baedc..35036fab58c4 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -21,6 +21,7 @@
 #include "accessors.h"
 #include "file-item.h"
 #include "super.h"
+#include "fscrypt.h"
 
 #define __MAX_CSUM_ITEMS(r, size) ((unsigned long)(((BTRFS_LEAF_DATA_SIZE(r) - \
 				   sizeof(struct btrfs_item) * 2) / \
@@ -1264,7 +1265,8 @@ int btrfs_csum_file_blocks(struct btrfs_trans_handle *trans,
 void btrfs_extent_item_to_extent_map(struct btrfs_inode *inode,
 				     const struct btrfs_path *path,
 				     struct btrfs_file_extent_item *fi,
-				     struct extent_map *em)
+				     struct extent_map *em,
+				     struct btrfs_fscrypt_ctx *ctx)
 {
 	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 	struct btrfs_root *root = inode->root;
@@ -1306,6 +1308,13 @@ void btrfs_extent_item_to_extent_map(struct btrfs_inode *inode,
 				set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
 		}
 		em->encryption_type = btrfs_file_extent_encryption(leaf, fi);
+		if (em->encryption_type != BTRFS_ENCRYPTION_NONE) {
+			ctx->size =
+				btrfs_file_extent_encryption_ctx_size(leaf, fi);
+			read_extent_buffer(leaf, ctx->ctx,
+				btrfs_file_extent_encryption_ctx_offset(fi),
+				ctx->size);
+		}
 	} else if (type == BTRFS_FILE_EXTENT_INLINE) {
 		em->block_start = EXTENT_MAP_INLINE;
 		em->start = extent_start;
diff --git a/fs/btrfs/file-item.h b/fs/btrfs/file-item.h
index 04bd2d34efb1..bb79014024bd 100644
--- a/fs/btrfs/file-item.h
+++ b/fs/btrfs/file-item.h
@@ -5,6 +5,8 @@
 
 #include "accessors.h"
 
+struct btrfs_fscrypt_ctx;
+
 #define BTRFS_FILE_EXTENT_INLINE_DATA_START		\
 		(offsetof(struct btrfs_file_extent_item, disk_bytenr))
 
@@ -63,7 +65,8 @@ int btrfs_lookup_csums_bitmap(struct btrfs_root *root, struct btrfs_path *path,
 void btrfs_extent_item_to_extent_map(struct btrfs_inode *inode,
 				     const struct btrfs_path *path,
 				     struct btrfs_file_extent_item *fi,
-				     struct extent_map *em);
+				     struct extent_map *em,
+				     struct btrfs_fscrypt_ctx *ctx);
 int btrfs_inode_clear_file_extent_range(struct btrfs_inode *inode, u64 start,
 					u64 len);
 int btrfs_inode_set_file_extent_range(struct btrfs_inode *inode, u64 start, u64 len);
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 70a801b90d13..edd37aa91a02 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -38,6 +38,7 @@
 #include "ioctl.h"
 #include "file.h"
 #include "super.h"
+#include "fscrypt.h"
 
 /* simple helper to fault in pages and copy.  This should go away
  * and be replaced with calls into generic code.
@@ -2276,6 +2277,14 @@ static int btrfs_insert_replace_extent(struct btrfs_trans_handle *trans,
 	btrfs_set_file_extent_num_bytes(leaf, extent, replace_len);
 	if (extent_info->is_new_extent)
 		btrfs_set_file_extent_generation(leaf, extent, trans->transid);
+	if (extent_info->fscrypt_info) {
+		ret = btrfs_fscrypt_save_extent_info(inode, path,
+						     extent_info->fscrypt_info);
+		if (ret) {
+			btrfs_release_path(path);
+			return ret;
+		}
+	}
 	btrfs_mark_buffer_dirty(trans, leaf);
 	btrfs_release_path(path);
 
diff --git a/fs/btrfs/fscrypt.c b/fs/btrfs/fscrypt.c
index 4fe0a8804ac5..7f53bfa621e1 100644
--- a/fs/btrfs/fscrypt.c
+++ b/fs/btrfs/fscrypt.c
@@ -214,6 +214,54 @@ static struct block_device **btrfs_fscrypt_get_devices(struct super_block *sb,
 	return devs;
 }
 
+int btrfs_fscrypt_load_extent_info(struct btrfs_inode *inode,
+				   struct extent_map *em,
+				   struct btrfs_fscrypt_ctx *ctx)
+{
+	struct fscrypt_extent_info *info;
+	unsigned long nofs_flag;
+
+	if (ctx->size == 0)
+		return 0;
+
+	nofs_flag = memalloc_nofs_save();
+	info = fscrypt_load_extent_info(&inode->vfs_inode, ctx->ctx, ctx->size);
+	memalloc_nofs_restore(nofs_flag);
+	if (IS_ERR(info))
+		return PTR_ERR(info);
+	em->fscrypt_info = info;
+	return 0;
+}
+
+int btrfs_fscrypt_save_extent_info(struct btrfs_inode *inode,
+				   struct btrfs_path *path,
+				   struct fscrypt_extent_info *info)
+{
+	struct btrfs_file_extent_item *ei;
+	u8 ctx[BTRFS_MAX_EXTENT_CTX_SIZE];
+	ssize_t ctx_size;
+
+	ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
+			    struct btrfs_file_extent_item);
+
+	ctx_size = fscrypt_set_extent_context(&inode->vfs_inode, info, ctx);
+	if (ctx_size < 0) {
+		btrfs_err_rl(inode->root->fs_info, "invalid encrypt context\n");
+		return (int)ctx_size;
+	}
+	write_extent_buffer(path->nodes[0], ctx,
+			    btrfs_file_extent_encryption_ctx_offset(ei),
+			    ctx_size);
+	btrfs_set_file_extent_encryption_ctx_size(path->nodes[0], ei, ctx_size);
+	return 0;
+}
+
+size_t btrfs_fscrypt_extent_context_size(struct btrfs_inode *inode)
+{
+	return sizeof(struct btrfs_encryption_info) +
+		fscrypt_extent_context_size(&inode->vfs_inode);
+}
+
 const struct fscrypt_operations btrfs_fscrypt_ops = {
 	.get_context = btrfs_fscrypt_get_context,
 	.set_context = btrfs_fscrypt_set_context,
diff --git a/fs/btrfs/fscrypt.h b/fs/btrfs/fscrypt.h
index c08fd52c99b4..2882a4a9d978 100644
--- a/fs/btrfs/fscrypt.h
+++ b/fs/btrfs/fscrypt.h
@@ -8,6 +8,11 @@
 
 #include "fs.h"
 
+struct btrfs_fscrypt_ctx {
+	u8 ctx[BTRFS_MAX_EXTENT_CTX_SIZE];
+	size_t size;
+};
+
 #ifdef CONFIG_FS_ENCRYPTION
 int btrfs_fscrypt_get_disk_name(struct extent_buffer *leaf,
 				struct btrfs_dir_item *di,
@@ -16,8 +21,29 @@ int btrfs_fscrypt_get_disk_name(struct extent_buffer *leaf,
 bool btrfs_fscrypt_match_name(struct fscrypt_name *fname,
 			      struct extent_buffer *leaf,
 			      unsigned long de_name, u32 de_name_len);
+int btrfs_fscrypt_load_extent_info(struct btrfs_inode *inode,
+				   struct extent_map *em,
+				   struct btrfs_fscrypt_ctx *ctx);
+int btrfs_fscrypt_save_extent_info(struct btrfs_inode *inode,
+				   struct btrfs_path *path,
+				   struct fscrypt_extent_info *fi);
+size_t btrfs_fscrypt_extent_context_size(struct btrfs_inode *inode);
 
 #else
+static inline int btrfs_fscrypt_save_extent_info(struct btrfs_inode *inode,
+						 struct btrfs_path *path,
+						 struct fscrypt_extent_info *fi)
+{
+	return 0;
+}
+
+static inline int btrfs_fscrypt_load_extent_info(struct btrfs_inode *inode,
+						 struct extent_map *em,
+						 struct btrfs_fscrypt_ctx *ctx)
+{
+	return 0;
+}
+
 static inline int btrfs_fscrypt_get_disk_name(struct extent_buffer *leaf,
 					      struct btrfs_dir_item *di,
 					      struct fscrypt_str *qstr)
@@ -35,6 +61,11 @@ static inline bool btrfs_fscrypt_match_name(struct fscrypt_name *fname,
 	return !memcmp_extent_buffer(leaf, fname->disk_name.name, de_name,
 				     de_name_len);
 }
+
+static inline size_t btrfs_fscrypt_extent_context_size(struct btrfs_inode *inode)
+{
+	return 0;
+}
 #endif /* CONFIG_FS_ENCRYPTION */
 
 extern const struct fscrypt_operations btrfs_fscrypt_ops;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index ee1ac2718ce3..9414991d6b6b 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2904,6 +2904,9 @@ static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
 	size_t fscrypt_context_size = 0;
 	int ret;
 
+	if (btrfs_stack_file_extent_encryption(stack_fi))
+		fscrypt_context_size = btrfs_fscrypt_extent_context_size(inode);
+
 	path = btrfs_alloc_path();
 	if (!path)
 		return -ENOMEM;
@@ -2942,6 +2945,12 @@ static int insert_reserved_file_extent(struct btrfs_trans_handle *trans,
 			btrfs_item_ptr_offset(leaf, path->slots[0]),
 			sizeof(struct btrfs_file_extent_item));
 
+	if (fscrypt_context_size) {
+		ret = btrfs_fscrypt_save_extent_info(inode, path, fscrypt_info);
+		if (ret)
+			goto out;
+	}
+
 	btrfs_mark_buffer_dirty(trans, leaf);
 	btrfs_release_path(path);
 
@@ -6866,6 +6875,7 @@ struct extent_map *btrfs_get_extent(struct btrfs_inode *inode,
 	struct btrfs_key found_key;
 	struct extent_map *em = NULL;
 	struct extent_map_tree *em_tree = &inode->extent_tree;
+	struct btrfs_fscrypt_ctx ctx;
 
 	read_lock(&em_tree->lock);
 	em = lookup_extent_mapping(em_tree, start, len);
@@ -6879,6 +6889,9 @@ struct extent_map *btrfs_get_extent(struct btrfs_inode *inode,
 		else
 			goto out;
 	}
+
+	ctx.size = 0;
+
 	em = alloc_extent_map();
 	if (!em) {
 		ret = -ENOMEM;
@@ -6983,7 +6996,7 @@ struct extent_map *btrfs_get_extent(struct btrfs_inode *inode,
 		goto insert;
 	}
 
-	btrfs_extent_item_to_extent_map(inode, path, item, em);
+	btrfs_extent_item_to_extent_map(inode, path, item, em, &ctx);
 
 	if (extent_type == BTRFS_FILE_EXTENT_REG ||
 	    extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
@@ -7028,6 +7041,10 @@ struct extent_map *btrfs_get_extent(struct btrfs_inode *inode,
 		goto out;
 	}
 
+	ret = btrfs_fscrypt_load_extent_info(inode, em, &ctx);
+	if (ret)
+		goto out;
+
 	write_lock(&em_tree->lock);
 	ret = btrfs_add_extent_mapping(fs_info, em_tree, &em, start, len);
 	write_unlock(&em_tree->lock);
@@ -9703,6 +9720,9 @@ static struct btrfs_trans_handle *insert_prealloc_file_extent(
 		return trans;
 	}
 
+	if (fscrypt_info)
+		fscrypt_context_size = btrfs_fscrypt_extent_context_size(inode);
+
 	extent_info.disk_offset = start;
 	extent_info.disk_len = len;
 	extent_info.data_offset = 0;
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 40dd5c652f0e..5200da6f5be3 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -30,6 +30,7 @@
 #include "file.h"
 #include "orphan.h"
 #include "tree-checker.h"
+#include "fscrypt.h"
 
 #define MAX_CONFLICT_INODES 10
 
@@ -4633,6 +4634,9 @@ static int log_one_extent(struct btrfs_trans_handle *trans,
 	size_t fscrypt_context_size = 0;
 	u8 encryption = em->encryption_type;
 
+	if (encryption)
+		fscrypt_context_size = btrfs_fscrypt_extent_context_size(inode);
+
 	btrfs_set_stack_file_extent_generation(&fi, trans->transid);
 	if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
 		btrfs_set_stack_file_extent_type(&fi, BTRFS_FILE_EXTENT_PREALLOC);
@@ -4693,6 +4697,12 @@ static int log_one_extent(struct btrfs_trans_handle *trans,
 	write_extent_buffer(leaf, &fi,
 			    btrfs_item_ptr_offset(leaf, path->slots[0]),
 			    sizeof(fi));
+	if (fscrypt_context_size) {
+		ret = btrfs_fscrypt_save_extent_info(inode, path,
+						     em->fscrypt_info);
+		if (ret)
+			return ret;
+	}
 	btrfs_mark_buffer_dirty(trans, leaf);
 
 	btrfs_release_path(path);
-- 
2.41.0

[PATCH 30/35] btrfs: setup fscrypt_extent_info for new extents

[Josef Bacik]

New extents for encrypted inodes must have a fscrypt_extent_info, which
has the necessary keys and does all the registration at the block layer
for them.  This is passed through all of the infrastructure we've
previously added to make sure the context gets saved properly with the
file extents.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/inode.c | 39 +++++++++++++++++++++++++++++++++++++--
 1 file changed, 37 insertions(+), 2 deletions(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 9414991d6b6b..aa536b838ce3 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -7398,7 +7398,20 @@ static struct extent_map *create_io_em(struct btrfs_inode *inode, u64 start,
 		set_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
 		em->compress_type = compress_type;
 	}
-	em->encryption_type = BTRFS_ENCRYPTION_NONE;
+
+	if (IS_ENCRYPTED(&inode->vfs_inode)) {
+		struct fscrypt_extent_info *fscrypt_info;
+
+		em->encryption_type = BTRFS_ENCRYPTION_FSCRYPT;
+		fscrypt_info = fscrypt_prepare_new_extent(&inode->vfs_inode);
+		if (IS_ERR(fscrypt_info)) {
+			free_extent_map(em);
+			return ERR_CAST(fscrypt_info);
+		}
+		em->fscrypt_info = fscrypt_info;
+	} else {
+		em->encryption_type = BTRFS_ENCRYPTION_NONE;
+	}
 
 	ret = btrfs_replace_extent_map_range(inode, em, true);
 	if (ret) {
@@ -9785,6 +9798,9 @@ static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
 	if (trans)
 		own_trans = false;
 	while (num_bytes > 0) {
+		struct fscrypt_extent_info *fscrypt_info = NULL;
+		int encryption_type = BTRFS_ENCRYPTION_NONE;
+
 		cur_bytes = min_t(u64, num_bytes, SZ_256M);
 		cur_bytes = max(cur_bytes, min_size);
 		/*
@@ -9799,6 +9815,20 @@ static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
 		if (ret)
 			break;
 
+		if (IS_ENCRYPTED(inode)) {
+			fscrypt_info = fscrypt_prepare_new_extent(inode);
+			if (IS_ERR(fscrypt_info)) {
+				btrfs_dec_block_group_reservations(fs_info,
+								   ins.objectid);
+				btrfs_free_reserved_extent(fs_info,
+							   ins.objectid,
+							   ins.offset, 0);
+				ret = PTR_ERR(fscrypt_info);
+				break;
+			}
+			encryption_type = BTRFS_ENCRYPTION_FSCRYPT;
+		}
+
 		/*
 		 * We've reserved this space, and thus converted it from
 		 * ->bytes_may_use to ->bytes_reserved.  Any error that happens
@@ -9810,7 +9840,8 @@ static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
 
 		last_alloc = ins.offset;
 		trans = insert_prealloc_file_extent(trans, BTRFS_I(inode),
-						    &ins, NULL, cur_offset);
+						    &ins, fscrypt_info,
+						    cur_offset);
 		/*
 		 * Now that we inserted the prealloc extent we can finally
 		 * decrement the number of reservations in the block group.
@@ -9820,6 +9851,7 @@ static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
 		btrfs_dec_block_group_reservations(fs_info, ins.objectid);
 		if (IS_ERR(trans)) {
 			ret = PTR_ERR(trans);
+			fscrypt_put_extent_info(fscrypt_info);
 			btrfs_free_reserved_extent(fs_info, ins.objectid,
 						   ins.offset, 0);
 			break;
@@ -9827,6 +9859,7 @@ static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
 
 		em = alloc_extent_map();
 		if (!em) {
+			fscrypt_put_extent_info(fscrypt_info);
 			btrfs_drop_extent_map_range(BTRFS_I(inode), cur_offset,
 					    cur_offset + ins.offset - 1, false);
 			btrfs_set_inode_full_sync(BTRFS_I(inode));
@@ -9842,6 +9875,8 @@ static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
 		em->ram_bytes = ins.offset;
 		set_bit(EXTENT_FLAG_PREALLOC, &em->flags);
 		em->generation = trans->transid;
+		em->fscrypt_info = fscrypt_info;
+		em->encryption_type = encryption_type;
 
 		ret = btrfs_replace_extent_map_range(BTRFS_I(inode), em, true);
 		free_extent_map(em);
-- 
2.41.0

[PATCH 31/35] btrfs: populate ordered_extent with the orig offset

[Josef Bacik]

For extent encryption we have to use a logical block nr as input for the
IV.  For btrfs we're using the offset into the extent we're operating
on.  For most ordered extents this is the same as the file_offset,
however for prealloc and NOCOW we have to use the original offset.

Add this as an argument and plumb it through everywhere, this will be
used when setting up the bio.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/inode.c        | 15 ++++++++++-----
 fs/btrfs/ordered-data.c | 22 ++++++++++++----------
 fs/btrfs/ordered-data.h | 12 +++++++++---
 3 files changed, 31 insertions(+), 18 deletions(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index aa536b838ce3..14420683651a 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1165,6 +1165,7 @@ static void submit_one_async_extent(struct async_chunk *async_chunk,
 
 	ordered = btrfs_alloc_ordered_extent(inode, em->fscrypt_info,
 				       start,			/* file_offset */
+				       start,			/* orig_start */
 				       async_extent->ram_size,	/* num_bytes */
 				       async_extent->ram_size,	/* ram_bytes */
 				       ins.objectid,		/* disk_bytenr */
@@ -1428,8 +1429,8 @@ static noinline int cow_file_range(struct btrfs_inode *inode,
 		}
 
 		ordered = btrfs_alloc_ordered_extent(inode, em->fscrypt_info,
-					start, ram_size, ram_size, ins.objectid,
-					cur_alloc_size, 0,
+					start, start, ram_size, ram_size,
+					ins.objectid, cur_alloc_size, 0,
 					1 << BTRFS_ORDERED_REGULAR,
 					BTRFS_COMPRESS_NONE);
 		free_extent_map(em);
@@ -2178,7 +2179,9 @@ static noinline int run_delalloc_nocow(struct btrfs_inode *inode,
 		}
 
 		ordered = btrfs_alloc_ordered_extent(inode, fscrypt_info,
-				cur_offset, nocow_args.num_bytes,
+				cur_offset,
+				found_key.offset - nocow_args.extent_offset,
+				nocow_args.num_bytes,
 				nocow_args.num_bytes, nocow_args.disk_bytenr,
 				nocow_args.num_bytes, 0,
 				is_prealloc
@@ -7088,8 +7091,9 @@ static struct extent_map *btrfs_create_dio_extent(struct btrfs_inode *inode,
 		fscrypt_info = orig_em->fscrypt_info;
 	}
 
-	ordered = btrfs_alloc_ordered_extent(inode, fscrypt_info, start, len,
-					     len, block_start, block_len, 0,
+	ordered = btrfs_alloc_ordered_extent(inode, fscrypt_info, start,
+					     orig_start, len, len, block_start,
+					     block_len, 0,
 					     (1 << type) |
 					     (1 << BTRFS_ORDERED_DIRECT),
 					     BTRFS_COMPRESS_NONE);
@@ -10612,6 +10616,7 @@ ssize_t btrfs_do_encoded_write(struct kiocb *iocb, struct iov_iter *from,
 	}
 
 	ordered = btrfs_alloc_ordered_extent(inode, em->fscrypt_info, start,
+				       start - encoded->unencoded_offset,
 				       num_bytes, ram_bytes, ins.objectid,
 				       ins.offset, encoded->unencoded_offset,
 				       (1 << BTRFS_ORDERED_ENCODED) |
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 81b0fe575011..172a6ca38987 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -149,9 +149,9 @@ static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree,
 static struct btrfs_ordered_extent *alloc_ordered_extent(
 			struct btrfs_inode *inode,
 			struct fscrypt_extent_info *fscrypt_info,
-			u64 file_offset, u64 num_bytes, u64 ram_bytes,
-			u64 disk_bytenr, u64 disk_num_bytes, u64 offset,
-			unsigned long flags, int compress_type)
+			u64 file_offset, u64 orig_offset, u64 num_bytes,
+			u64 ram_bytes, u64 disk_bytenr, u64 disk_num_bytes,
+			u64 offset, unsigned long flags, int compress_type)
 {
 	struct btrfs_ordered_extent *entry;
 	int ret;
@@ -176,6 +176,7 @@ static struct btrfs_ordered_extent *alloc_ordered_extent(
 		return ERR_PTR(-ENOMEM);
 
 	entry->file_offset = file_offset;
+	entry->orig_offset = orig_offset;
 	entry->num_bytes = num_bytes;
 	entry->ram_bytes = ram_bytes;
 	entry->disk_bytenr = disk_bytenr;
@@ -254,6 +255,7 @@ static void insert_ordered_extent(struct btrfs_ordered_extent *entry)
  * @inode:           Inode that this extent is for.
  * @fscrypt_info:    The fscrypt_extent_info for this extent, if necessary.
  * @file_offset:     Logical offset in file where the extent starts.
+ * @orig_offset:     Logical offset of the original extent (PREALLOC or NOCOW)
  * @num_bytes:       Logical length of extent in file.
  * @ram_bytes:       Full length of unencoded data.
  * @disk_bytenr:     Offset of extent on disk.
@@ -271,17 +273,17 @@ static void insert_ordered_extent(struct btrfs_ordered_extent *entry)
 struct btrfs_ordered_extent *btrfs_alloc_ordered_extent(
 			struct btrfs_inode *inode,
 			struct fscrypt_extent_info *fscrypt_info,
-			u64 file_offset, u64 num_bytes, u64 ram_bytes,
-			u64 disk_bytenr, u64 disk_num_bytes, u64 offset,
-			unsigned long flags, int compress_type)
+			u64 file_offset, u64 orig_offset, u64 num_bytes,
+			u64 ram_bytes, u64 disk_bytenr, u64 disk_num_bytes,
+			u64 offset, unsigned long flags, int compress_type)
 {
 	struct btrfs_ordered_extent *entry;
 
 	ASSERT((flags & ~BTRFS_ORDERED_TYPE_FLAGS) == 0);
 
 	entry = alloc_ordered_extent(inode, fscrypt_info, file_offset,
-				     num_bytes, ram_bytes, disk_bytenr,
-				     disk_num_bytes, offset, flags,
+				     orig_offset, num_bytes, ram_bytes,
+				     disk_bytenr, disk_num_bytes, offset, flags,
 				     compress_type);
 	if (!IS_ERR(entry))
 		insert_ordered_extent(entry);
@@ -1189,8 +1191,8 @@ struct btrfs_ordered_extent *btrfs_split_ordered_extent(
 		return ERR_PTR(-EINVAL);
 
 	new = alloc_ordered_extent(inode, ordered->fscrypt_info, file_offset,
-				   len, len, disk_bytenr, len, 0, flags,
-				   ordered->compress_type);
+				   ordered->orig_offset, len, len, disk_bytenr,
+				   len, 0, flags, ordered->compress_type);
 	if (IS_ERR(new))
 		return new;
 
diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
index e19e62d5171a..b5b969716d13 100644
--- a/fs/btrfs/ordered-data.h
+++ b/fs/btrfs/ordered-data.h
@@ -90,6 +90,12 @@ struct btrfs_ordered_extent {
 	/* logical offset in the file */
 	u64 file_offset;
 
+	/*
+	 * The original logical offset of the extent, this is for NOCOW and
+	 * PREALLOC extents, otherwise it'll be the same as file_offset.
+	 */
+	u64 orig_offset;
+
 	/*
 	 * These fields directly correspond to the same fields in
 	 * btrfs_file_extent_item.
@@ -187,9 +193,9 @@ bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode,
 struct btrfs_ordered_extent *btrfs_alloc_ordered_extent(
 			struct btrfs_inode *inode,
 			struct fscrypt_extent_info *fscrypt_info,
-			u64 file_offset, u64 num_bytes, u64 ram_bytes,
-			u64 disk_bytenr, u64 disk_num_bytes, u64 offset,
-			unsigned long flags, int compress_type);
+			u64 file_offset, u64 orig_offset, u64 num_bytes,
+			u64 ram_bytes, u64 disk_bytenr, u64 disk_num_bytes,
+			u64 offset, unsigned long flags, int compress_type);
 void btrfs_add_ordered_sum(struct btrfs_ordered_extent *entry,
 			   struct btrfs_ordered_sum *sum);
 struct btrfs_ordered_extent *btrfs_lookup_ordered_extent(struct btrfs_inode *inode,
-- 
2.41.0

[PATCH 32/35] btrfs: set the bio fscrypt context when applicable

[Josef Bacik]

Now that we have the fscrypt_info plumbed through everywhere, add the
code to setup the bio encryption context from the extent context.

We use the per-extent fscrypt_extent_info for encryption/decryption.
We use the offset into the extent as the lblk for fscrypt.  So the start
of the extent has the lblk of 0, 4k into the extent has the lblk of 4k,
etc.  This is done to allow things like relocation to continue to work
properly.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/compression.c |  6 ++++
 fs/btrfs/extent_io.c   | 63 +++++++++++++++++++++++++++++++++++++++++-
 fs/btrfs/fscrypt.c     | 36 ++++++++++++++++++++++++
 fs/btrfs/fscrypt.h     | 22 +++++++++++++++
 fs/btrfs/inode.c       | 10 +++++++
 5 files changed, 136 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 19b22b4653c8..3f586ee40b94 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -36,6 +36,7 @@
 #include "zoned.h"
 #include "file-item.h"
 #include "super.h"
+#include "fscrypt.h"
 
 static struct bio_set btrfs_compressed_bioset;
 
@@ -301,6 +302,9 @@ void btrfs_submit_compressed_write(struct btrfs_ordered_extent *ordered,
 	cb->bbio.ordered = ordered;
 	btrfs_add_compressed_bio_pages(cb);
 
+	btrfs_set_bio_crypt_ctx_from_extent(&cb->bbio.bio, inode,
+					    ordered->fscrypt_info, 0);
+
 	btrfs_submit_bio(&cb->bbio, 0);
 }
 
@@ -504,6 +508,8 @@ void btrfs_submit_compressed_read(struct btrfs_bio *bbio)
 	cb->compress_type = em->compress_type;
 	cb->orig_bbio = bbio;
 
+	btrfs_set_bio_crypt_ctx_from_extent(&cb->bbio.bio, inode,
+					    em->fscrypt_info, 0);
 	free_extent_map(em);
 
 	cb->nr_pages = DIV_ROUND_UP(compressed_len, PAGE_SIZE);
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 121746b7ce95..49f6bbe3b75b 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -37,6 +37,7 @@
 #include "dev-replace.h"
 #include "super.h"
 #include "transaction.h"
+#include "fscrypt.h"
 
 static struct kmem_cache *extent_buffer_cache;
 
@@ -103,6 +104,10 @@ struct btrfs_bio_ctrl {
 	blk_opf_t opf;
 	btrfs_bio_end_io_t end_io_func;
 	struct writeback_control *wbc;
+
+	/* This is set for reads and we have encryption. */
+	struct fscrypt_extent_info *fscrypt_info;
+	u64 orig_start;
 };
 
 static void submit_one_bio(struct btrfs_bio_ctrl *bio_ctrl)
@@ -707,10 +712,31 @@ static bool btrfs_bio_is_contig(struct btrfs_bio_ctrl *bio_ctrl,
 				struct page *page, u64 disk_bytenr,
 				unsigned int pg_offset)
 {
-	struct bio *bio = &bio_ctrl->bbio->bio;
+	struct inode *inode = page->mapping->host;
+	struct btrfs_bio *bbio = bio_ctrl->bbio;
+	struct bio *bio = &bbio->bio;
 	struct bio_vec *bvec = bio_last_bvec_all(bio);
 	const sector_t sector = disk_bytenr >> SECTOR_SHIFT;
 
+	if (IS_ENCRYPTED(inode)) {
+		u64 file_offset = page_offset(page) + pg_offset;
+		u64 offset = 0;
+		struct fscrypt_extent_info *fscrypt_info = NULL;
+
+		/* bio_ctrl->fscrypt_info is only set in the READ case. */
+		if (bio_ctrl->fscrypt_info) {
+			offset = file_offset - bio_ctrl->orig_start;
+			fscrypt_info = bio_ctrl->fscrypt_info;
+		} else if (bbio->ordered) {
+			fscrypt_info = bbio->ordered->fscrypt_info;
+			offset = file_offset - bbio->ordered->orig_offset;
+		}
+
+		if (!btrfs_mergeable_encrypted_bio(bio, inode, fscrypt_info,
+						   offset))
+			return false;
+	}
+
 	if (bio_ctrl->compress_type != BTRFS_COMPRESS_NONE) {
 		/*
 		 * For compression, all IO should have its logical bytenr set
@@ -741,6 +767,8 @@ static void alloc_new_bio(struct btrfs_inode *inode,
 {
 	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 	struct btrfs_bio *bbio;
+	struct fscrypt_extent_info *fscrypt_info = NULL;
+	u64 offset = 0;
 
 	bbio = btrfs_bio_alloc(BIO_MAX_VECS, bio_ctrl->opf, fs_info,
 			       bio_ctrl->end_io_func, NULL);
@@ -760,6 +788,8 @@ static void alloc_new_bio(struct btrfs_inode *inode,
 					ordered->file_offset +
 					ordered->disk_num_bytes - file_offset);
 			bbio->ordered = ordered;
+			fscrypt_info = ordered->fscrypt_info;
+			offset = file_offset - ordered->orig_offset;
 		}
 
 		/*
@@ -770,7 +800,13 @@ static void alloc_new_bio(struct btrfs_inode *inode,
 		 */
 		bio_set_dev(&bbio->bio, fs_info->fs_devices->latest_dev->bdev);
 		wbc_init_bio(bio_ctrl->wbc, &bbio->bio);
+	} else {
+		fscrypt_info = bio_ctrl->fscrypt_info;
+		offset = file_offset - bio_ctrl->orig_start;
 	}
+
+	btrfs_set_bio_crypt_ctx_from_extent(&bbio->bio, inode, fscrypt_info,
+					    offset);
 }
 
 /*
@@ -1004,6 +1040,8 @@ static int btrfs_do_readpage(struct page *page, struct extent_map **em_cached,
 		bool force_bio_submit = false;
 		u64 disk_bytenr;
 
+		bio_ctrl->fscrypt_info = NULL;
+
 		ASSERT(IS_ALIGNED(cur, fs_info->sectorsize));
 		if (cur >= last_byte) {
 			iosize = PAGE_SIZE - pg_offset;
@@ -1078,6 +1116,22 @@ static int btrfs_do_readpage(struct page *page, struct extent_map **em_cached,
 		if (prev_em_start)
 			*prev_em_start = em->start;
 
+		/*
+		 * We use the extent offset for the IV when decrypting the page,
+		 * so we have to set the extent_offset based on the orig_start
+		 * for this extent.  Also save the fscrypt_info so the bio ctx
+		 * can be set properly.  If this inode isn't encrypted this
+		 * won't do anything.
+		 *
+		 * If we're compressed we'll handle all of this in
+		 * btrfs_submit_compressed_read.
+		 */
+		if (compress_type == BTRFS_COMPRESS_NONE) {
+			bio_ctrl->orig_start = em->orig_start;
+			bio_ctrl->fscrypt_info =
+				fscrypt_get_extent_info(em->fscrypt_info);
+		}
+
 		free_extent_map(em);
 		em = NULL;
 
@@ -1089,6 +1143,9 @@ static int btrfs_do_readpage(struct page *page, struct extent_map **em_cached,
 			end_page_read(page, true, cur, iosize);
 			cur = cur + iosize;
 			pg_offset += iosize;
+
+			/* This shouldn't be set, but clear it just in case. */
+			fscrypt_put_extent_info(bio_ctrl->fscrypt_info);
 			continue;
 		}
 		/* the get_extent function already copied into the page */
@@ -1097,6 +1154,9 @@ static int btrfs_do_readpage(struct page *page, struct extent_map **em_cached,
 			end_page_read(page, true, cur, iosize);
 			cur = cur + iosize;
 			pg_offset += iosize;
+
+			/* This shouldn't be set, but clear it just in case. */
+			fscrypt_put_extent_info(bio_ctrl->fscrypt_info);
 			continue;
 		}
 
@@ -1109,6 +1169,7 @@ static int btrfs_do_readpage(struct page *page, struct extent_map **em_cached,
 			submit_one_bio(bio_ctrl);
 		submit_extent_page(bio_ctrl, disk_bytenr, page, iosize,
 				   pg_offset);
+		fscrypt_put_extent_info(bio_ctrl->fscrypt_info);
 		cur = cur + iosize;
 		pg_offset += iosize;
 	}
diff --git a/fs/btrfs/fscrypt.c b/fs/btrfs/fscrypt.c
index 7f53bfa621e1..1c690fcd0693 100644
--- a/fs/btrfs/fscrypt.c
+++ b/fs/btrfs/fscrypt.c
@@ -262,6 +262,42 @@ size_t btrfs_fscrypt_extent_context_size(struct btrfs_inode *inode)
 		fscrypt_extent_context_size(&inode->vfs_inode);
 }
 
+void btrfs_set_bio_crypt_ctx_from_extent(struct bio *bio,
+					 struct btrfs_inode *inode,
+					 struct fscrypt_extent_info *fi,
+					 u64 logical_offset)
+{
+	if (!fi)
+		return;
+
+	/*
+	 * fscrypt uses bytes >> s_blocksize_bits for the block numbers, so we
+	 * have to adjust everything based on our sectorsize so that the DUN
+	 * calculations are correct.
+	 */
+	logical_offset = div64_u64(logical_offset,
+				   inode->root->fs_info->sectorsize);
+	fscrypt_set_bio_crypt_ctx_from_extent(bio, &inode->vfs_inode, fi,
+					      logical_offset, GFP_NOFS);
+}
+
+bool btrfs_mergeable_encrypted_bio(struct bio *bio, struct inode *inode,
+				   struct fscrypt_extent_info *fi,
+				   u64 logical_offset)
+{
+	if (!fi)
+		return true;
+
+	/*
+	 * fscrypt uses bytes >> s_blocksize_bits for the block numbers, so we
+	 * have to adjust everything based on our sectorsize so that the DUN
+	 * calculations are correct.
+	 */
+	logical_offset = div64_u64(logical_offset,
+				   BTRFS_I(inode)->root->fs_info->sectorsize);
+	return fscrypt_mergeable_extent_bio(bio, inode, fi, logical_offset);
+}
+
 const struct fscrypt_operations btrfs_fscrypt_ops = {
 	.get_context = btrfs_fscrypt_get_context,
 	.set_context = btrfs_fscrypt_set_context,
diff --git a/fs/btrfs/fscrypt.h b/fs/btrfs/fscrypt.h
index 2882a4a9d978..756375ade0b6 100644
--- a/fs/btrfs/fscrypt.h
+++ b/fs/btrfs/fscrypt.h
@@ -28,6 +28,13 @@ int btrfs_fscrypt_save_extent_info(struct btrfs_inode *inode,
 				   struct btrfs_path *path,
 				   struct fscrypt_extent_info *fi);
 size_t btrfs_fscrypt_extent_context_size(struct btrfs_inode *inode);
+void btrfs_set_bio_crypt_ctx_from_extent(struct bio *bio,
+					 struct btrfs_inode *inode,
+					 struct fscrypt_extent_info *fi,
+					 u64 logical_offset);
+bool btrfs_mergeable_encrypted_bio(struct bio *bio, struct inode *inode,
+				   struct fscrypt_extent_info *fi,
+				   u64 logical_offset);
 
 #else
 static inline int btrfs_fscrypt_save_extent_info(struct btrfs_inode *inode,
@@ -66,6 +73,21 @@ static inline size_t btrfs_fscrypt_extent_context_size(struct btrfs_inode *inode
 {
 	return 0;
 }
+
+static inline void btrfs_set_bio_crypt_ctx_from_extent(struct bio *bio,
+						       struct btrfs_inode *inode,
+						       struct fscrypt_extent_info *fi,
+						       u64 logical_offset)
+{
+}
+
+static inline bool btrfs_mergeable_encrypted_bio(struct bio *bio,
+						 struct inode *inode,
+						 struct fscrypt_extent_info *fi,
+						 u64 logical_offset)
+{
+	return true;
+}
 #endif /* CONFIG_FS_ENCRYPTION */
 
 extern const struct fscrypt_operations btrfs_fscrypt_ops;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 14420683651a..fbcabc9a79fe 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -7897,6 +7897,8 @@ static void btrfs_dio_submit_io(const struct iomap_iter *iter, struct bio *bio,
 	struct btrfs_dio_private *dip =
 		container_of(bbio, struct btrfs_dio_private, bbio);
 	struct btrfs_dio_data *dio_data = iter->private;
+	struct fscrypt_extent_info *fscrypt_info = NULL;
+	u64 offset = 0;
 
 	btrfs_bio_init(bbio, BTRFS_I(iter->inode)->root->fs_info,
 		       btrfs_dio_end_io, bio->bi_private);
@@ -7918,6 +7920,9 @@ static void btrfs_dio_submit_io(const struct iomap_iter *iter, struct bio *bio,
 	if (iter->flags & IOMAP_WRITE) {
 		int ret;
 
+		offset = file_offset - dio_data->ordered->orig_offset;
+		fscrypt_info = dio_data->ordered->fscrypt_info;
+
 		ret = btrfs_extract_ordered_extent(bbio, dio_data->ordered);
 		if (ret) {
 			btrfs_finish_ordered_extent(dio_data->ordered, NULL,
@@ -7927,8 +7932,13 @@ static void btrfs_dio_submit_io(const struct iomap_iter *iter, struct bio *bio,
 			iomap_dio_bio_end_io(bio);
 			return;
 		}
+	} else {
+		fscrypt_info = dio_data->fscrypt_info;
+		offset = file_offset - dio_data->orig_start;
 	}
 
+	btrfs_set_bio_crypt_ctx_from_extent(&bbio->bio, bbio->inode,
+					    fscrypt_info, offset);
 	btrfs_submit_bio(bbio, 0);
 }
 
-- 
2.41.0

[PATCH 33/35] btrfs: add a bio argument to btrfs_csum_one_bio

[Josef Bacik]

We only ever needed the bbio in btrfs_csum_one_bio, since that has the
bio embedded in it.  However with encryption we'll have a different bio
with the encrypted data in it, and the original bbio.  Update
btrfs_csum_one_bio to take the bio we're going to csum as an argument,
which will allow us to csum the encrypted bio and stuff the csums into
the corresponding bbio to be used later when the IO completes.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/bio.c       | 2 +-
 fs/btrfs/file-item.c | 3 +--
 fs/btrfs/file-item.h | 2 +-
 3 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/fs/btrfs/bio.c b/fs/btrfs/bio.c
index 4f3b693a16b1..90e4d4709fa3 100644
--- a/fs/btrfs/bio.c
+++ b/fs/btrfs/bio.c
@@ -533,7 +533,7 @@ static blk_status_t btrfs_bio_csum(struct btrfs_bio *bbio)
 {
 	if (bbio->bio.bi_opf & REQ_META)
 		return btree_csum_one_bio(bbio);
-	return btrfs_csum_one_bio(bbio);
+	return btrfs_csum_one_bio(bbio, &bbio->bio);
 }
 
 /*
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index 35036fab58c4..d925d6d98bf4 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -730,13 +730,12 @@ int btrfs_lookup_csums_bitmap(struct btrfs_root *root, struct btrfs_path *path,
 /*
  * Calculate checksums of the data contained inside a bio.
  */
-blk_status_t btrfs_csum_one_bio(struct btrfs_bio *bbio)
+blk_status_t btrfs_csum_one_bio(struct btrfs_bio *bbio, struct bio *bio)
 {
 	struct btrfs_ordered_extent *ordered = bbio->ordered;
 	struct btrfs_inode *inode = bbio->inode;
 	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
-	struct bio *bio = &bbio->bio;
 	struct btrfs_ordered_sum *sums;
 	char *data;
 	struct bvec_iter iter;
diff --git a/fs/btrfs/file-item.h b/fs/btrfs/file-item.h
index bb79014024bd..e52d5d71d533 100644
--- a/fs/btrfs/file-item.h
+++ b/fs/btrfs/file-item.h
@@ -51,7 +51,7 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
 int btrfs_csum_file_blocks(struct btrfs_trans_handle *trans,
 			   struct btrfs_root *root,
 			   struct btrfs_ordered_sum *sums);
-blk_status_t btrfs_csum_one_bio(struct btrfs_bio *bbio);
+blk_status_t btrfs_csum_one_bio(struct btrfs_bio *bbio, struct bio *bio);
 blk_status_t btrfs_alloc_dummy_sum(struct btrfs_bio *bbio);
 int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end,
 			     struct list_head *list, int search_commit,
-- 
2.41.0

[PATCH 34/35] btrfs: add orig_logical to btrfs_bio

[Josef Bacik]

When checksumming the encrypted bio on writes we need to know which
logical address this checksum is for.  At the point where we get the
encrypted bio the bi_sector is the physical location on the target disk,
so we need to save the original logical offset in the btrfs_bio.  Then
we can use this when csum'ing the bio instead of the
bio->iter.bi_sector.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/bio.c       | 9 +++++++++
 fs/btrfs/bio.h       | 3 +++
 fs/btrfs/file-item.c | 2 +-
 3 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/bio.c b/fs/btrfs/bio.c
index 90e4d4709fa3..7d6931e53beb 100644
--- a/fs/btrfs/bio.c
+++ b/fs/btrfs/bio.c
@@ -96,6 +96,7 @@ static struct btrfs_bio *btrfs_split_bio(struct btrfs_fs_info *fs_info,
 	if (bbio_has_ordered_extent(bbio)) {
 		refcount_inc(&orig_bbio->ordered->refs);
 		bbio->ordered = orig_bbio->ordered;
+		orig_bbio->orig_logical += map_length;
 	}
 	atomic_inc(&orig_bbio->pending_ios);
 	return bbio;
@@ -674,6 +675,14 @@ static bool btrfs_submit_chunk(struct btrfs_bio *bbio, int mirror_num)
 		goto fail;
 	}
 
+	/*
+	 * For fscrypt writes we will get the encrypted bio after we've remapped
+	 * our bio to the physical disk location, so we need to save the
+	 * original bytenr so we know what we're checksumming.
+	 */
+	if (bio_op(bio) == REQ_OP_WRITE && is_data_bbio(bbio))
+		bbio->orig_logical = logical;
+
 	map_length = min(map_length, length);
 	if (use_append)
 		map_length = min(map_length, fs_info->max_zone_append_size);
diff --git a/fs/btrfs/bio.h b/fs/btrfs/bio.h
index ca79decee060..5d3f53dcd6d5 100644
--- a/fs/btrfs/bio.h
+++ b/fs/btrfs/bio.h
@@ -54,11 +54,14 @@ struct btrfs_bio {
 		 * - pointer to the checksums for this bio
 		 * - original physical address from the allocator
 		 *   (for zone append only)
+		 * - original logical address, used for checksumming fscrypt
+		 *   bios.
 		 */
 		struct {
 			struct btrfs_ordered_extent *ordered;
 			struct btrfs_ordered_sum *sums;
 			u64 orig_physical;
+			u64 orig_logical;
 		};
 
 		/* For metadata reads: parentness verification. */
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index d925d6d98bf4..26e3bc602655 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -756,7 +756,7 @@ blk_status_t btrfs_csum_one_bio(struct btrfs_bio *bbio, struct bio *bio)
 	sums->len = bio->bi_iter.bi_size;
 	INIT_LIST_HEAD(&sums->list);
 
-	sums->logical = bio->bi_iter.bi_sector << SECTOR_SHIFT;
+	sums->logical = bbio->orig_logical;
 	index = 0;
 
 	shash->tfm = fs_info->csum_shash;
-- 
2.41.0

[PATCH 35/35] btrfs: implement process_bio cb for fscrypt

[Josef Bacik]

We are going to be checksumming the encrypted data, so we have to
implement the ->process_bio fscrypt callback.  This will provide us with
the original bio and the encrypted bio to do work on.  For WRITE's this
will happen after the encrypted bio has been encrypted.  For READ's this
will happen after the read has completed and before the decryption step
is done.

For write's this is straightforward, we can just pass in the encrypted
bio to btrfs_csum_one_bio and then the csums will be added to the bbio
as normal.

For read's this is relatively straightforward, but requires some care.
We assume (because that's how it works currently) that the encrypted bio
match the original bio, this is important because we save the iter of
the bio before we submit.  If this changes in the future we'll need a
hook to give us the bi_iter of the decryption bio before it's submitted.
We check the csums before decryption.  If it doesn't match we simply
error out and we let the normal path handle the repair work.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/bio.c     | 34 +++++++++++++++++++++++++++++++++-
 fs/btrfs/bio.h     |  3 +++
 fs/btrfs/fscrypt.c | 19 +++++++++++++++++++
 3 files changed, 55 insertions(+), 1 deletion(-)

diff --git a/fs/btrfs/bio.c b/fs/btrfs/bio.c
index 7d6931e53beb..27ebf6373c8f 100644
--- a/fs/btrfs/bio.c
+++ b/fs/btrfs/bio.c
@@ -280,6 +280,34 @@ static struct btrfs_failed_bio *repair_one_sector(struct btrfs_bio *failed_bbio,
 	return fbio;
 }
 
+blk_status_t btrfs_check_encrypted_read_bio(struct btrfs_bio *bbio,
+					    struct bio *enc_bio)
+{
+	struct btrfs_inode *inode = bbio->inode;
+	struct btrfs_fs_info *fs_info = inode->root->fs_info;
+	u32 sectorsize = fs_info->sectorsize;
+	struct bvec_iter iter = bbio->saved_iter;
+	struct btrfs_device *dev = bbio->bio.bi_private;
+	u32 offset = 0;
+
+	/*
+	 * We have to use a copy of iter in case there's an error,
+	 * btrfs_check_read_bio will handle submitting the repair bios.
+	 */
+	while (iter.bi_size) {
+		struct bio_vec bv = bio_iter_iovec(enc_bio, iter);
+
+		bv.bv_len = min(bv.bv_len, sectorsize);
+		if (!btrfs_data_csum_ok(bbio, dev, offset, &bv))
+			return BLK_STS_IOERR;
+		bio_advance_iter_single(enc_bio, &iter, sectorsize);
+		offset += sectorsize;
+	}
+
+	bbio->csum_done = true;
+	return BLK_STS_OK;
+}
+
 static void btrfs_check_read_bio(struct btrfs_bio *bbio, struct btrfs_device *dev)
 {
 	struct btrfs_inode *inode = bbio->inode;
@@ -305,6 +333,10 @@ static void btrfs_check_read_bio(struct btrfs_bio *bbio, struct btrfs_device *de
 	/* Clear the I/O error. A failed repair will reset it. */
 	bbio->bio.bi_status = BLK_STS_OK;
 
+	/* This was an encrypted bio and we've already done the csum check. */
+	if (status == BLK_STS_OK && bbio->csum_done)
+		goto out;
+
 	while (iter->bi_size) {
 		struct bio_vec bv = bio_iter_iovec(&bbio->bio, *iter);
 
@@ -315,7 +347,7 @@ static void btrfs_check_read_bio(struct btrfs_bio *bbio, struct btrfs_device *de
 		bio_advance_iter_single(&bbio->bio, iter, sectorsize);
 		offset += sectorsize;
 	}
-
+out:
 	if (bbio->csum != bbio->csum_inline)
 		kfree(bbio->csum);
 
diff --git a/fs/btrfs/bio.h b/fs/btrfs/bio.h
index 5d3f53dcd6d5..393ef32f5321 100644
--- a/fs/btrfs/bio.h
+++ b/fs/btrfs/bio.h
@@ -45,6 +45,7 @@ struct btrfs_bio {
 		struct {
 			u8 *csum;
 			u8 csum_inline[BTRFS_BIO_INLINE_CSUM_SIZE];
+			bool csum_done;
 			struct bvec_iter saved_iter;
 		};
 
@@ -110,5 +111,7 @@ void btrfs_submit_repair_write(struct btrfs_bio *bbio, int mirror_num, bool dev_
 int btrfs_repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start,
 			    u64 length, u64 logical, struct page *page,
 			    unsigned int pg_offset, int mirror_num);
+blk_status_t btrfs_check_encrypted_read_bio(struct btrfs_bio *bbio,
+					    struct bio *enc_bio);
 
 #endif
diff --git a/fs/btrfs/fscrypt.c b/fs/btrfs/fscrypt.c
index 1c690fcd0693..b2dfc26221e7 100644
--- a/fs/btrfs/fscrypt.c
+++ b/fs/btrfs/fscrypt.c
@@ -15,6 +15,7 @@
 #include "transaction.h"
 #include "volumes.h"
 #include "xattr.h"
+#include "file-item.h"
 
 /*
  * From a given location in a leaf, read a name into a qstr (usually a
@@ -214,6 +215,23 @@ static struct block_device **btrfs_fscrypt_get_devices(struct super_block *sb,
 	return devs;
 }
 
+static blk_status_t btrfs_process_encrypted_bio(struct bio *orig_bio,
+						struct bio *enc_bio)
+{
+	struct btrfs_bio *bbio = btrfs_bio(orig_bio);
+
+	if (bio_op(orig_bio) == REQ_OP_READ) {
+		/*
+		 * We have ->saved_iter based on the orig_bio, so if the block
+		 * layer changes we need to notice this asap so we can update
+		 * our code to handle the new world order.
+		 */
+		ASSERT(orig_bio == enc_bio);
+		return btrfs_check_encrypted_read_bio(bbio, enc_bio);
+	}
+	return btrfs_csum_one_bio(bbio, enc_bio);
+}
+
 int btrfs_fscrypt_load_extent_info(struct btrfs_inode *inode,
 				   struct extent_map *em,
 				   struct btrfs_fscrypt_ctx *ctx)
@@ -303,5 +321,6 @@ const struct fscrypt_operations btrfs_fscrypt_ops = {
 	.set_context = btrfs_fscrypt_set_context,
 	.empty_dir = btrfs_fscrypt_empty_dir,
 	.get_devices = btrfs_fscrypt_get_devices,
+	.process_bio = btrfs_process_encrypted_bio,
 	.key_prefix = "btrfs:"
 };
-- 
2.41.0

Re: [PATCH 13/35] btrfs: adapt readdir for encrypted and nokey names

[kernel test robot]

Hi Josef,

kernel test robot noticed the following build warnings:

[auto build test WARNING on kdave/for-next]
[cannot apply to axboe-block/for-next linus/master v6.6-rc4 next-20231004]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Josef-Bacik/fscrypt-rename-fscrypt_info-fscrypt_inode_info/20230927-020531
base:   https://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux.git for-next
patch link:    https://lore.kernel.org/r/e405fffae735ea6a250c58bd7ad199281f111f9a.1695750478.git.josef%40toxicpanda.com
patch subject: [PATCH 13/35] btrfs: adapt readdir for encrypted and nokey names
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <yujie.liu@intel.com>
| Closes: https://lore.kernel.org/r/202310050449.35KiNskt-lkp@intel.com/

includecheck warnings: (new ones prefixed by >>)
>> fs/btrfs/fscrypt.c: ioctl.h is included more than once.

vim +8 fs/btrfs/fscrypt.c

     2	
     3	#include <linux/iversion.h>
     4	#include "ctree.h"
     5	#include "accessors.h"
     6	#include "btrfs_inode.h"
     7	#include "disk-io.h"
   > 8	#include "ioctl.h"
     9	#include "fs.h"
    10	#include "fscrypt.h"
  > 11	#include "ioctl.h"
    12	#include "messages.h"
    13	#include "root-tree.h"
    14	#include "transaction.h"
    15	#include "xattr.h"
    16	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki