fscrypt API cleanups v2

fscrypt API cleanups v2

[Christoph Hellwig]

Hi all,

this series cleans up various fscrypt APIs to pass logical offsets in
and lengths in bytes, and on-disk sectors as 512-byte sector units,
like most of the VFS and block code.

Changes since v1:
 - remove all buffer_head helpers, and do that before the API cleanups
   to simplify the series
 - fix a bisection hazard
 - spelling fixes in the commit logs
 - use "file position" to describe the byte offset into an inode
 - add another small ext4 cleanup at the end

Diffstat:
 fs/buffer.c                 |   17 ++++++++
 fs/crypto/bio.c             |   37 ++++++++----------
 fs/crypto/fscrypt_private.h |    3 -
 fs/crypto/inline_crypt.c    |   86 ++++----------------------------------------
 fs/crypto/keysetup.c        |    2 -
 fs/ext4/inode.c             |    5 ++
 fs/ext4/page-io.c           |   28 ++++++++++----
 fs/ext4/readpage.c          |   10 ++---
 fs/f2fs/data.c              |    7 ++-
 fs/f2fs/file.c              |    4 +-
 fs/iomap/direct-io.c        |    6 +--
 include/linux/fscrypt.h     |   37 ++++--------------
 12 files changed, 89 insertions(+), 153 deletions(-)

[PATCH 01/14] ext4: initialize the write hint in io_submit_init_bio

[Christoph Hellwig]

Make io_submit_init_bio complete by also initializing the write hint.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/ext4/page-io.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index a8c95eee91b7..a3644d6cb65f 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -416,6 +416,7 @@ void ext4_io_submit_init(struct ext4_io_submit *io,
 }
 
 static void io_submit_init_bio(struct ext4_io_submit *io,
+			       struct inode *inode,
 			       struct buffer_head *bh)
 {
 	struct bio *bio;
@@ -430,6 +431,7 @@ static void io_submit_init_bio(struct ext4_io_submit *io,
 	bio->bi_end_io = ext4_end_bio;
 	bio->bi_private = ext4_get_io_end(io->io_end);
 	io->io_bio = bio;
+	io->io_bio->bi_write_hint = inode->i_write_hint;
 	io->io_next_block = bh->b_blocknr;
 	wbc_init_bio(io->io_wbc, bio);
 }
@@ -445,10 +447,8 @@ static void io_submit_add_bh(struct ext4_io_submit *io,
 submit_and_retry:
 		ext4_io_submit(io);
 	}
-	if (io->io_bio == NULL) {
-		io_submit_init_bio(io, bh);
-		io->io_bio->bi_write_hint = inode->i_write_hint;
-	}
+	if (io->io_bio == NULL)
+		io_submit_init_bio(io, inode, bh);
 	if (!bio_add_folio(io->io_bio, io_folio, bh->b_size, bh_offset(bh)))
 		goto submit_and_retry;
 	wbc_account_cgroup_owner(io->io_wbc, folio, bh->b_size);
-- 
2.47.3

Re: [PATCH 01/14] ext4: initialize the write hint in io_submit_init_bio

[Eric Biggers]

On Thu, Feb 26, 2026 at 06:49:21AM -0800, Christoph Hellwig wrote:
> Make io_submit_init_bio complete by also initializing the write hint.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  fs/ext4/page-io.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
> index a8c95eee91b7..a3644d6cb65f 100644
> --- a/fs/ext4/page-io.c
> +++ b/fs/ext4/page-io.c
> @@ -416,6 +416,7 @@ void ext4_io_submit_init(struct ext4_io_submit *io,
>  }
>  
>  static void io_submit_init_bio(struct ext4_io_submit *io,
> +			       struct inode *inode,
>  			       struct buffer_head *bh)
>  {
>  	struct bio *bio;
> @@ -430,6 +431,7 @@ static void io_submit_init_bio(struct ext4_io_submit *io,
>  	bio->bi_end_io = ext4_end_bio;
>  	bio->bi_private = ext4_get_io_end(io->io_end);
>  	io->io_bio = bio;
> +	io->io_bio->bi_write_hint = inode->i_write_hint;
>  	io->io_next_block = bh->b_blocknr;
>  	wbc_init_bio(io->io_wbc, bio);
>  }

Maybe make this consistent with the other initializations by moving it
up a line and doing:

        bio->bi_write_hint = inode->i_write_hint;

- Eric

[PATCH 02/14] ext4: open code fscrypt_set_bio_crypt_ctx_bh

[Christoph Hellwig]

io_submit_init_bio already has or can easily get at most information
needed to set the crypto context.  Open code fscrypt_set_bio_crypt_ctx_bh
based on that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/ext4/page-io.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index a3644d6cb65f..851d1267054a 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -417,6 +417,7 @@ void ext4_io_submit_init(struct ext4_io_submit *io,
 
 static void io_submit_init_bio(struct ext4_io_submit *io,
 			       struct inode *inode,
+			       struct folio *io_folio,
 			       struct buffer_head *bh)
 {
 	struct bio *bio;
@@ -426,7 +427,10 @@ static void io_submit_init_bio(struct ext4_io_submit *io,
 	 * __GFP_DIRECT_RECLAIM is set, see comments for bio_alloc_bioset().
 	 */
 	bio = bio_alloc(bh->b_bdev, BIO_MAX_VECS, REQ_OP_WRITE, GFP_NOIO);
-	fscrypt_set_bio_crypt_ctx_bh(bio, bh, GFP_NOIO);
+	fscrypt_set_bio_crypt_ctx(bio, inode,
+			(folio_pos(io_folio) + bh_offset(bh)) >>
+				inode->i_blkbits,
+			GFP_NOIO);
 	bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
 	bio->bi_end_io = ext4_end_bio;
 	bio->bi_private = ext4_get_io_end(io->io_end);
@@ -448,7 +452,7 @@ static void io_submit_add_bh(struct ext4_io_submit *io,
 		ext4_io_submit(io);
 	}
 	if (io->io_bio == NULL)
-		io_submit_init_bio(io, inode, bh);
+		io_submit_init_bio(io, inode, io_folio, bh);
 	if (!bio_add_folio(io->io_bio, io_folio, bh->b_size, bh_offset(bh)))
 		goto submit_and_retry;
 	wbc_account_cgroup_owner(io->io_wbc, folio, bh->b_size);
-- 
2.47.3

Re: [PATCH 02/14] ext4: open code fscrypt_set_bio_crypt_ctx_bh

[Eric Biggers]

On Thu, Feb 26, 2026 at 06:49:22AM -0800, Christoph Hellwig wrote:
> io_submit_init_bio already has or can easily get at most information
> needed to set the crypto context.  Open code fscrypt_set_bio_crypt_ctx_bh
> based on that.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  fs/ext4/page-io.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
> index a3644d6cb65f..851d1267054a 100644
> --- a/fs/ext4/page-io.c
> +++ b/fs/ext4/page-io.c
> @@ -417,6 +417,7 @@ void ext4_io_submit_init(struct ext4_io_submit *io,
>  
>  static void io_submit_init_bio(struct ext4_io_submit *io,
>  			       struct inode *inode,
> +			       struct folio *io_folio,
>  			       struct buffer_head *bh)
>  {
>  	struct bio *bio;
> @@ -426,7 +427,10 @@ static void io_submit_init_bio(struct ext4_io_submit *io,
>  	 * __GFP_DIRECT_RECLAIM is set, see comments for bio_alloc_bioset().
>  	 */
>  	bio = bio_alloc(bh->b_bdev, BIO_MAX_VECS, REQ_OP_WRITE, GFP_NOIO);
> -	fscrypt_set_bio_crypt_ctx_bh(bio, bh, GFP_NOIO);
> +	fscrypt_set_bio_crypt_ctx(bio, inode,
> +			(folio_pos(io_folio) + bh_offset(bh)) >>
> +				inode->i_blkbits,
> +			GFP_NOIO);
>  	bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
>  	bio->bi_end_io = ext4_end_bio;
>  	bio->bi_private = ext4_get_io_end(io->io_end);
> @@ -448,7 +452,7 @@ static void io_submit_add_bh(struct ext4_io_submit *io,
>  		ext4_io_submit(io);
>  	}
>  	if (io->io_bio == NULL)
> -		io_submit_init_bio(io, inode, bh);
> +		io_submit_init_bio(io, inode, io_folio, bh);
>  	if (!bio_add_folio(io->io_bio, io_folio, bh->b_size, bh_offset(bh)))
>  		goto submit_and_retry;

This should use 'folio', not 'io_folio'.  folio_pos() works only for
pagecache folios.

- Eric

[PATCH 03/14] ext4: factor out a io_submit_need_new_bio helper

[Christoph Hellwig]

Factor out a helper to prepare for making this logic a bit more
complex in the next commit.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/ext4/page-io.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 851d1267054a..88226979c503 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -440,14 +440,23 @@ static void io_submit_init_bio(struct ext4_io_submit *io,
 	wbc_init_bio(io->io_wbc, bio);
 }
 
+static bool io_submit_need_new_bio(struct ext4_io_submit *io,
+				   struct buffer_head *bh)
+{
+	if (bh->b_blocknr != io->io_next_block)
+		return true;
+	if (!fscrypt_mergeable_bio_bh(io->io_bio, bh))
+		return true;
+	return false;
+}
+
 static void io_submit_add_bh(struct ext4_io_submit *io,
 			     struct inode *inode,
 			     struct folio *folio,
 			     struct folio *io_folio,
 			     struct buffer_head *bh)
 {
-	if (io->io_bio && (bh->b_blocknr != io->io_next_block ||
-			   !fscrypt_mergeable_bio_bh(io->io_bio, bh))) {
+	if (io->io_bio && io_submit_need_new_bio(io, bh)) {
 submit_and_retry:
 		ext4_io_submit(io);
 	}
-- 
2.47.3

[PATCH 04/14] ext4, fscrypt: merge fscrypt_mergeable_bio_bh into io_submit_need_new_bio

[Christoph Hellwig]

ext4 already has the inode and folio and can't have a NULL
folio->mapping in this path. Open code fscrypt_mergeable_bio_bh in
io_submit_need_new_bio based on these simplifying assumptions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/crypto/inline_crypt.c | 23 -----------------------
 fs/ext4/page-io.c        |  8 ++++++--
 include/linux/fscrypt.h  |  9 ---------
 3 files changed, 6 insertions(+), 34 deletions(-)

diff --git a/fs/crypto/inline_crypt.c b/fs/crypto/inline_crypt.c
index c0852b920dbc..0da53956a9b1 100644
--- a/fs/crypto/inline_crypt.c
+++ b/fs/crypto/inline_crypt.c
@@ -406,29 +406,6 @@ bool fscrypt_mergeable_bio(struct bio *bio, const struct inode *inode,
 }
 EXPORT_SYMBOL_GPL(fscrypt_mergeable_bio);
 
-/**
- * fscrypt_mergeable_bio_bh() - test whether data can be added to a bio
- * @bio: the bio being built up
- * @next_bh: the next buffer_head for which I/O will be submitted
- *
- * Same as fscrypt_mergeable_bio(), except this takes a buffer_head instead of
- * an inode and block number directly.
- *
- * Return: true iff the I/O is mergeable
- */
-bool fscrypt_mergeable_bio_bh(struct bio *bio,
-			      const struct buffer_head *next_bh)
-{
-	const struct inode *inode;
-	u64 next_lblk;
-
-	if (!bh_get_inode_and_lblk_num(next_bh, &inode, &next_lblk))
-		return !bio->bi_crypt_context;
-
-	return fscrypt_mergeable_bio(bio, inode, next_lblk);
-}
-EXPORT_SYMBOL_GPL(fscrypt_mergeable_bio_bh);
-
 /**
  * fscrypt_dio_supported() - check whether DIO (direct I/O) is supported on an
  *			     inode, as far as encryption is concerned
diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 88226979c503..3db3c19a29e5 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -441,11 +441,15 @@ static void io_submit_init_bio(struct ext4_io_submit *io,
 }
 
 static bool io_submit_need_new_bio(struct ext4_io_submit *io,
+				   struct inode *inode,
+				   struct folio *io_folio,
 				   struct buffer_head *bh)
 {
 	if (bh->b_blocknr != io->io_next_block)
 		return true;
-	if (!fscrypt_mergeable_bio_bh(io->io_bio, bh))
+	if (!fscrypt_mergeable_bio(io->io_bio, inode,
+			(folio_pos(io_folio) + bh_offset(bh)) >>
+			 inode->i_blkbits))
 		return true;
 	return false;
 }
@@ -456,7 +460,7 @@ static void io_submit_add_bh(struct ext4_io_submit *io,
 			     struct folio *io_folio,
 			     struct buffer_head *bh)
 {
-	if (io->io_bio && io_submit_need_new_bio(io, bh)) {
+	if (io->io_bio && io_submit_need_new_bio(io, inode, io_folio, bh)) {
 submit_and_retry:
 		ext4_io_submit(io);
 	}
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 516aba5b858b..6af3c1907adc 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -876,9 +876,6 @@ void fscrypt_set_bio_crypt_ctx_bh(struct bio *bio,
 bool fscrypt_mergeable_bio(struct bio *bio, const struct inode *inode,
 			   u64 next_lblk);
 
-bool fscrypt_mergeable_bio_bh(struct bio *bio,
-			      const struct buffer_head *next_bh);
-
 bool fscrypt_dio_supported(struct inode *inode);
 
 u64 fscrypt_limit_io_blocks(const struct inode *inode, u64 lblk, u64 nr_blocks);
@@ -906,12 +903,6 @@ static inline bool fscrypt_mergeable_bio(struct bio *bio,
 	return true;
 }
 
-static inline bool fscrypt_mergeable_bio_bh(struct bio *bio,
-					    const struct buffer_head *next_bh)
-{
-	return true;
-}
-
 static inline bool fscrypt_dio_supported(struct inode *inode)
 {
 	return !fscrypt_needs_contents_encryption(inode);
-- 
2.47.3

Re: [PATCH 04/14] ext4, fscrypt: merge fscrypt_mergeable_bio_bh into io_submit_need_new_bio

[Eric Biggers]

On Thu, Feb 26, 2026 at 06:49:24AM -0800, Christoph Hellwig wrote:
> ext4 already has the inode and folio and can't have a NULL
> folio->mapping in this path. Open code fscrypt_mergeable_bio_bh in
> io_submit_need_new_bio based on these simplifying assumptions.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  fs/crypto/inline_crypt.c | 23 -----------------------
>  fs/ext4/page-io.c        |  8 ++++++--
>  include/linux/fscrypt.h  |  9 ---------
>  3 files changed, 6 insertions(+), 34 deletions(-)
> 
> diff --git a/fs/crypto/inline_crypt.c b/fs/crypto/inline_crypt.c
> index c0852b920dbc..0da53956a9b1 100644
> --- a/fs/crypto/inline_crypt.c
> +++ b/fs/crypto/inline_crypt.c
> @@ -406,29 +406,6 @@ bool fscrypt_mergeable_bio(struct bio *bio, const struct inode *inode,
>  }
>  EXPORT_SYMBOL_GPL(fscrypt_mergeable_bio);
>  
> -/**
> - * fscrypt_mergeable_bio_bh() - test whether data can be added to a bio
> - * @bio: the bio being built up
> - * @next_bh: the next buffer_head for which I/O will be submitted
> - *
> - * Same as fscrypt_mergeable_bio(), except this takes a buffer_head instead of
> - * an inode and block number directly.
> - *
> - * Return: true iff the I/O is mergeable
> - */
> -bool fscrypt_mergeable_bio_bh(struct bio *bio,
> -			      const struct buffer_head *next_bh)
> -{
> -	const struct inode *inode;
> -	u64 next_lblk;
> -
> -	if (!bh_get_inode_and_lblk_num(next_bh, &inode, &next_lblk))
> -		return !bio->bi_crypt_context;
> -
> -	return fscrypt_mergeable_bio(bio, inode, next_lblk);
> -}
> -EXPORT_SYMBOL_GPL(fscrypt_mergeable_bio_bh);
> -
>  /**
>   * fscrypt_dio_supported() - check whether DIO (direct I/O) is supported on an
>   *			     inode, as far as encryption is concerned
> diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
> index 88226979c503..3db3c19a29e5 100644
> --- a/fs/ext4/page-io.c
> +++ b/fs/ext4/page-io.c
> @@ -441,11 +441,15 @@ static void io_submit_init_bio(struct ext4_io_submit *io,
>  }
>  
>  static bool io_submit_need_new_bio(struct ext4_io_submit *io,
> +				   struct inode *inode,
> +				   struct folio *io_folio,
>  				   struct buffer_head *bh)
>  {
>  	if (bh->b_blocknr != io->io_next_block)
>  		return true;
> -	if (!fscrypt_mergeable_bio_bh(io->io_bio, bh))
> +	if (!fscrypt_mergeable_bio(io->io_bio, inode,
> +			(folio_pos(io_folio) + bh_offset(bh)) >>
> +			 inode->i_blkbits))
>  		return true;
>  	return false;
>  }
> @@ -456,7 +460,7 @@ static void io_submit_add_bh(struct ext4_io_submit *io,
>  			     struct folio *io_folio,
>  			     struct buffer_head *bh)
>  {
> -	if (io->io_bio && io_submit_need_new_bio(io, bh)) {
> +	if (io->io_bio && io_submit_need_new_bio(io, inode, io_folio, bh)) {
>  submit_and_retry:
>  		ext4_io_submit(io);
>  	}

As in patch 2, this needs to use 'folio', not 'io_folio'.

- Eric

[PATCH 05/14] fscrypt: move fscrypt_set_bio_crypt_ctx_bh to buffer.c

[Christoph Hellwig]

fscrypt_set_bio_crypt_ctx_bh is only used by submit_bh_wbc now.  Move it
there and merge bh_get_inode_and_lblk_num into it.

Note that this does not add ifdefs for fscrypt as the compiler will
optimize away the dead code if it is not built in.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/buffer.c              | 20 +++++++++++++++++-
 fs/crypto/inline_crypt.c | 45 ----------------------------------------
 include/linux/fscrypt.h  |  9 --------
 3 files changed, 19 insertions(+), 55 deletions(-)

diff --git a/fs/buffer.c b/fs/buffer.c
index 22b43642ba57..e1e95463e06b 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -2774,6 +2774,24 @@ static void end_bio_bh_io_sync(struct bio *bio)
 	bio_put(bio);
 }
 
+static void buffer_set_crypto_ctx(struct bio *bio, const struct buffer_head *bh,
+				  gfp_t gfp_mask)
+{
+	const struct address_space *mapping = folio_mapping(bh->b_folio);
+	const struct inode *inode;
+	u64 lblk;
+
+	/*
+	 * The ext4 journal (jbd2) can submit a buffer_head it directly created
+	 * for a non-pagecache page.  fscrypt doesn't care about these.
+	 */
+	if (!mapping)
+		return;
+	inode = mapping->host;
+	lblk = (folio_pos(bh->b_folio) + bh_offset(bh)) >> inode->i_blkbits;
+	fscrypt_set_bio_crypt_ctx(bio, inode, lblk, gfp_mask);
+}
+
 static void submit_bh_wbc(blk_opf_t opf, struct buffer_head *bh,
 			  enum rw_hint write_hint,
 			  struct writeback_control *wbc)
@@ -2800,7 +2818,7 @@ static void submit_bh_wbc(blk_opf_t opf, struct buffer_head *bh,
 
 	bio = bio_alloc(bh->b_bdev, 1, opf, GFP_NOIO);
 
-	fscrypt_set_bio_crypt_ctx_bh(bio, bh, GFP_NOIO);
+	buffer_set_crypto_ctx(bio, bh, GFP_NOIO);
 
 	bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
 	bio->bi_write_hint = write_hint;
diff --git a/fs/crypto/inline_crypt.c b/fs/crypto/inline_crypt.c
index 0da53956a9b1..702d13d138aa 100644
--- a/fs/crypto/inline_crypt.c
+++ b/fs/crypto/inline_crypt.c
@@ -314,51 +314,6 @@ void fscrypt_set_bio_crypt_ctx(struct bio *bio, const struct inode *inode,
 }
 EXPORT_SYMBOL_GPL(fscrypt_set_bio_crypt_ctx);
 
-/* 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,
-				      u64 *lblk_num_ret)
-{
-	struct folio *folio = bh->b_folio;
-	const struct address_space *mapping;
-	const struct inode *inode;
-
-	/*
-	 * The ext4 journal (jbd2) can submit a buffer_head it directly created
-	 * for a non-pagecache page.  fscrypt doesn't care about these.
-	 */
-	mapping = folio_mapping(folio);
-	if (!mapping)
-		return false;
-	inode = mapping->host;
-
-	*inode_ret = inode;
-	*lblk_num_ret = (folio_pos(folio) + bh_offset(bh)) >> inode->i_blkbits;
-	return true;
-}
-
-/**
- * fscrypt_set_bio_crypt_ctx_bh() - prepare a file contents bio for inline
- *				    crypto
- * @bio: a bio which will eventually be submitted to the file
- * @first_bh: the first buffer_head for which I/O will be submitted
- * @gfp_mask: memory allocation flags
- *
- * Same as fscrypt_set_bio_crypt_ctx(), except this takes a buffer_head instead
- * of an inode and block number directly.
- */
-void fscrypt_set_bio_crypt_ctx_bh(struct bio *bio,
-				  const struct buffer_head *first_bh,
-				  gfp_t gfp_mask)
-{
-	const struct inode *inode;
-	u64 first_lblk;
-
-	if (bh_get_inode_and_lblk_num(first_bh, &inode, &first_lblk))
-		fscrypt_set_bio_crypt_ctx(bio, inode, first_lblk, gfp_mask);
-}
-EXPORT_SYMBOL_GPL(fscrypt_set_bio_crypt_ctx_bh);
-
 /**
  * fscrypt_mergeable_bio() - test whether data can be added to a bio
  * @bio: the bio being built up
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 6af3c1907adc..26561b7994e0 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -869,10 +869,6 @@ 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_bh(struct bio *bio,
-				  const struct buffer_head *first_bh,
-				  gfp_t gfp_mask);
-
 bool fscrypt_mergeable_bio(struct bio *bio, const struct inode *inode,
 			   u64 next_lblk);
 
@@ -891,11 +887,6 @@ 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_bh(
-					 struct bio *bio,
-					 const struct buffer_head *first_bh,
-					 gfp_t gfp_mask) { }
-
 static inline bool fscrypt_mergeable_bio(struct bio *bio,
 					 const struct inode *inode,
 					 u64 next_lblk)
-- 
2.47.3

Re: [PATCH 05/14] fscrypt: move fscrypt_set_bio_crypt_ctx_bh to buffer.c

[Eric Biggers]

On Thu, Feb 26, 2026 at 06:49:25AM -0800, Christoph Hellwig wrote:
> Note that this does not add ifdefs for fscrypt as the compiler will
> optimize away the dead code if it is not built in.

The call to folio_mapping() isn't optimized out, so it might still be
worth adding an IS_ENABLED(CONFIG_FS_ENCRYPTION).

- Eric

[PATCH 06/14] fscrypt: pass a byte offset to fscrypt_generate_dun

[Christoph Hellwig]

Logical offsets into an inode are usually expressed as bytes in the VFS.
Switch fscrypt_generate_dun to that convention and remove the
ci_data_units_per_block_bits member in struct fscrypt_inode_info that
was only used to cache the DUN shift based on the logical block size
granularity.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/crypto/fscrypt_private.h |  3 ---
 fs/crypto/inline_crypt.c    | 10 ++++------
 fs/crypto/keysetup.c        |  2 --
 3 files changed, 4 insertions(+), 11 deletions(-)

diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
index 4e8e82a9ccf9..8d3c278a7591 100644
--- a/fs/crypto/fscrypt_private.h
+++ b/fs/crypto/fscrypt_private.h
@@ -278,9 +278,6 @@ struct fscrypt_inode_info {
 	 */
 	u8 ci_data_unit_bits;
 
-	/* Cached value: log2 of number of data units per FS block */
-	u8 ci_data_units_per_block_bits;
-
 	/* Hashed inode number.  Only set for IV_INO_LBLK_32 */
 	u32 ci_hashed_ino;
 
diff --git a/fs/crypto/inline_crypt.c b/fs/crypto/inline_crypt.c
index 702d13d138aa..5279565e9846 100644
--- a/fs/crypto/inline_crypt.c
+++ b/fs/crypto/inline_crypt.c
@@ -268,14 +268,12 @@ 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_inode_info *ci,
-				 u64 lblk_num,
-				 u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE])
+				 loff_t pos, u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE])
 {
-	u64 index = lblk_num << ci->ci_data_units_per_block_bits;
 	union fscrypt_iv iv;
 	int i;
 
-	fscrypt_generate_iv(&iv, index, ci);
+	fscrypt_generate_iv(&iv, pos >> ci->ci_data_unit_bits, ci);
 
 	BUILD_BUG_ON(FSCRYPT_MAX_IV_SIZE > BLK_CRYPTO_MAX_IV_SIZE);
 	memset(dun, 0, BLK_CRYPTO_MAX_IV_SIZE);
@@ -309,7 +307,7 @@ void fscrypt_set_bio_crypt_ctx(struct bio *bio, const struct inode *inode,
 		return;
 	ci = fscrypt_get_inode_info_raw(inode);
 
-	fscrypt_generate_dun(ci, first_lblk, dun);
+	fscrypt_generate_dun(ci, first_lblk << inode->i_blkbits, dun);
 	bio_crypt_set_ctx(bio, ci->ci_enc_key.blk_key, dun, gfp_mask);
 }
 EXPORT_SYMBOL_GPL(fscrypt_set_bio_crypt_ctx);
@@ -356,7 +354,7 @@ bool fscrypt_mergeable_bio(struct bio *bio, const struct inode *inode,
 	if (bc->bc_key != ci->ci_enc_key.blk_key)
 		return false;
 
-	fscrypt_generate_dun(ci, next_lblk, next_dun);
+	fscrypt_generate_dun(ci, next_lblk << inode->i_blkbits, next_dun);
 	return bio_crypt_dun_is_contiguous(bc, bio->bi_iter.bi_size, next_dun);
 }
 EXPORT_SYMBOL_GPL(fscrypt_mergeable_bio);
diff --git a/fs/crypto/keysetup.c b/fs/crypto/keysetup.c
index 40fa05688d3a..d83257e9945e 100644
--- a/fs/crypto/keysetup.c
+++ b/fs/crypto/keysetup.c
@@ -609,8 +609,6 @@ fscrypt_setup_encryption_info(struct inode *inode,
 
 	crypt_info->ci_data_unit_bits =
 		fscrypt_policy_du_bits(&crypt_info->ci_policy, inode);
-	crypt_info->ci_data_units_per_block_bits =
-		inode->i_blkbits - crypt_info->ci_data_unit_bits;
 
 	res = setup_file_encryption_key(crypt_info, need_dirhash_key, &mk);
 	if (res)
-- 
2.47.3

[PATCH 07/14] fscrypt: pass a byte offset to fscrypt_mergeable_bio

[Christoph Hellwig]

Logical offsets into an inode are usually expressed as bytes in the VFS.
Switch fscrypt_mergeable_bio to that convention.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/crypto/bio.c          | 3 ++-
 fs/crypto/inline_crypt.c | 6 +++---
 fs/ext4/page-io.c        | 3 +--
 fs/ext4/readpage.c       | 3 ++-
 fs/f2fs/data.c           | 3 ++-
 include/linux/fscrypt.h  | 4 ++--
 6 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/fs/crypto/bio.c b/fs/crypto/bio.c
index 6da683ea69dc..0a701d4a17ef 100644
--- a/fs/crypto/bio.c
+++ b/fs/crypto/bio.c
@@ -100,7 +100,8 @@ static int fscrypt_zeroout_range_inline_crypt(const struct inode *inode,
 			len -= blocks_this_page;
 			lblk += blocks_this_page;
 			sector += (bytes_this_page >> SECTOR_SHIFT);
-			if (!len || !fscrypt_mergeable_bio(bio, inode, lblk))
+			if (!len || !fscrypt_mergeable_bio(bio, inode,
+					(loff_t)lblk << blockbits))
 				break;
 		}
 
diff --git a/fs/crypto/inline_crypt.c b/fs/crypto/inline_crypt.c
index 5279565e9846..b0954d17904b 100644
--- a/fs/crypto/inline_crypt.c
+++ b/fs/crypto/inline_crypt.c
@@ -316,7 +316,7 @@ EXPORT_SYMBOL_GPL(fscrypt_set_bio_crypt_ctx);
  * fscrypt_mergeable_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
- * @next_lblk: the next file logical block number in the I/O
+ * @pos: the next file position (in bytes) 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
@@ -334,7 +334,7 @@ EXPORT_SYMBOL_GPL(fscrypt_set_bio_crypt_ctx);
  * Return: true iff the I/O is mergeable
  */
 bool fscrypt_mergeable_bio(struct bio *bio, const struct inode *inode,
-			   u64 next_lblk)
+			   loff_t pos)
 {
 	const struct bio_crypt_ctx *bc = bio->bi_crypt_context;
 	const struct fscrypt_inode_info *ci;
@@ -354,7 +354,7 @@ bool fscrypt_mergeable_bio(struct bio *bio, const struct inode *inode,
 	if (bc->bc_key != ci->ci_enc_key.blk_key)
 		return false;
 
-	fscrypt_generate_dun(ci, next_lblk << inode->i_blkbits, next_dun);
+	fscrypt_generate_dun(ci, pos, next_dun);
 	return bio_crypt_dun_is_contiguous(bc, bio->bi_iter.bi_size, next_dun);
 }
 EXPORT_SYMBOL_GPL(fscrypt_mergeable_bio);
diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 3db3c19a29e5..5df5e7e6adde 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -448,8 +448,7 @@ static bool io_submit_need_new_bio(struct ext4_io_submit *io,
 	if (bh->b_blocknr != io->io_next_block)
 		return true;
 	if (!fscrypt_mergeable_bio(io->io_bio, inode,
-			(folio_pos(io_folio) + bh_offset(bh)) >>
-			 inode->i_blkbits))
+			folio_pos(io_folio) + bh_offset(bh)))
 		return true;
 	return false;
 }
diff --git a/fs/ext4/readpage.c b/fs/ext4/readpage.c
index 830f3b8a321f..ba7cfddd6038 100644
--- a/fs/ext4/readpage.c
+++ b/fs/ext4/readpage.c
@@ -342,7 +342,8 @@ static int ext4_mpage_readpages(struct inode *inode, struct fsverity_info *vi,
 		 * BIO off first?
 		 */
 		if (bio && (last_block_in_bio != first_block - 1 ||
-			    !fscrypt_mergeable_bio(bio, inode, next_block))) {
+			    !fscrypt_mergeable_bio(bio, inode,
+				(loff_t)next_block << blkbits))) {
 		submit_and_realloc:
 			blk_crypto_submit_bio(bio);
 			bio = NULL;
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 338df7a2aea6..dca273fedfde 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -541,7 +541,8 @@ static bool f2fs_crypt_mergeable_bio(struct bio *bio, const struct inode *inode,
 	if (fio && fio->encrypted_page)
 		return !bio_has_crypt_ctx(bio);
 
-	return fscrypt_mergeable_bio(bio, inode, next_idx);
+	return fscrypt_mergeable_bio(bio, inode,
+			(loff_t)next_idx << inode->i_blkbits);
 }
 
 void f2fs_submit_read_bio(struct f2fs_sb_info *sbi, struct bio *bio,
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 26561b7994e0..98fb14660d40 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -870,7 +870,7 @@ void fscrypt_set_bio_crypt_ctx(struct bio *bio,
 			       gfp_t gfp_mask);
 
 bool fscrypt_mergeable_bio(struct bio *bio, const struct inode *inode,
-			   u64 next_lblk);
+			   loff_t pos);
 
 bool fscrypt_dio_supported(struct inode *inode);
 
@@ -889,7 +889,7 @@ static inline void fscrypt_set_bio_crypt_ctx(struct bio *bio,
 
 static inline bool fscrypt_mergeable_bio(struct bio *bio,
 					 const struct inode *inode,
-					 u64 next_lblk)
+					 loff_t pos)
 {
 	return true;
 }
-- 
2.47.3

[PATCH 08/14] fscrypt: pass a byte offset to fscrypt_set_bio_crypt_ctx

[Christoph Hellwig]

Logical offsets into an inode are usually expressed as bytes in the VFS.
Switch fscrypt_set_bio_crypt_ctx to that convention.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/buffer.c              | 7 ++-----
 fs/crypto/bio.c          | 8 ++++----
 fs/crypto/inline_crypt.c | 6 +++---
 fs/ext4/page-io.c        | 4 +---
 fs/ext4/readpage.c       | 4 ++--
 fs/f2fs/data.c           | 4 +++-
 fs/iomap/direct-io.c     | 6 ++----
 include/linux/fscrypt.h  | 7 +++----
 8 files changed, 20 insertions(+), 26 deletions(-)

diff --git a/fs/buffer.c b/fs/buffer.c
index e1e95463e06b..4e3edaffbf43 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -2778,8 +2778,6 @@ static void buffer_set_crypto_ctx(struct bio *bio, const struct buffer_head *bh,
 				  gfp_t gfp_mask)
 {
 	const struct address_space *mapping = folio_mapping(bh->b_folio);
-	const struct inode *inode;
-	u64 lblk;
 
 	/*
 	 * The ext4 journal (jbd2) can submit a buffer_head it directly created
@@ -2787,9 +2785,8 @@ static void buffer_set_crypto_ctx(struct bio *bio, const struct buffer_head *bh,
 	 */
 	if (!mapping)
 		return;
-	inode = mapping->host;
-	lblk = (folio_pos(bh->b_folio) + bh_offset(bh)) >> inode->i_blkbits;
-	fscrypt_set_bio_crypt_ctx(bio, inode, lblk, gfp_mask);
+	fscrypt_set_bio_crypt_ctx(bio, mapping->host,
+			folio_pos(bh->b_folio) + bh_offset(bh), gfp_mask);
 }
 
 static void submit_bh_wbc(blk_opf_t opf, struct buffer_head *bh,
diff --git a/fs/crypto/bio.c b/fs/crypto/bio.c
index 0a701d4a17ef..e7fb2fdd9728 100644
--- a/fs/crypto/bio.c
+++ b/fs/crypto/bio.c
@@ -75,6 +75,7 @@ static int fscrypt_zeroout_range_inline_crypt(const struct inode *inode,
 {
 	const unsigned int blockbits = inode->i_blkbits;
 	const unsigned int blocks_per_page = 1 << (PAGE_SHIFT - blockbits);
+	loff_t pos = (loff_t)lblk << blockbits;
 	struct fscrypt_zero_done done = {
 		.pending	= ATOMIC_INIT(1),
 		.done		= COMPLETION_INITIALIZER_ONSTACK(done.done),
@@ -89,7 +90,7 @@ static int fscrypt_zeroout_range_inline_crypt(const struct inode *inode,
 		bio->bi_iter.bi_sector = sector;
 		bio->bi_private = &done;
 		bio->bi_end_io = fscrypt_zeroout_range_end_io;
-		fscrypt_set_bio_crypt_ctx(bio, inode, lblk, GFP_NOFS);
+		fscrypt_set_bio_crypt_ctx(bio, inode, pos, GFP_NOFS);
 
 		for (n = 0; n < BIO_MAX_VECS; n++) {
 			unsigned int blocks_this_page =
@@ -98,10 +99,9 @@ static int fscrypt_zeroout_range_inline_crypt(const struct inode *inode,
 
 			__bio_add_page(bio, ZERO_PAGE(0), bytes_this_page, 0);
 			len -= blocks_this_page;
-			lblk += blocks_this_page;
+			pos += bytes_this_page;
 			sector += (bytes_this_page >> SECTOR_SHIFT);
-			if (!len || !fscrypt_mergeable_bio(bio, inode,
-					(loff_t)lblk << blockbits))
+			if (!len || !fscrypt_mergeable_bio(bio, inode, pos))
 				break;
 		}
 
diff --git a/fs/crypto/inline_crypt.c b/fs/crypto/inline_crypt.c
index b0954d17904b..37d42d357925 100644
--- a/fs/crypto/inline_crypt.c
+++ b/fs/crypto/inline_crypt.c
@@ -285,7 +285,7 @@ static void fscrypt_generate_dun(const struct fscrypt_inode_info *ci,
  * 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
- * @first_lblk: the first file logical block number in the I/O
+ * @pos: the first file position (in bytes) in the I/O
  * @gfp_mask: memory allocation flags - these must be a waiting mask so that
  *					bio_crypt_set_ctx can't fail.
  *
@@ -298,7 +298,7 @@ static void fscrypt_generate_dun(const struct fscrypt_inode_info *ci,
  * The encryption context will be freed automatically when the bio is freed.
  */
 void fscrypt_set_bio_crypt_ctx(struct bio *bio, const struct inode *inode,
-			       u64 first_lblk, gfp_t gfp_mask)
+			       loff_t pos, gfp_t gfp_mask)
 {
 	const struct fscrypt_inode_info *ci;
 	u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE];
@@ -307,7 +307,7 @@ void fscrypt_set_bio_crypt_ctx(struct bio *bio, const struct inode *inode,
 		return;
 	ci = fscrypt_get_inode_info_raw(inode);
 
-	fscrypt_generate_dun(ci, first_lblk << inode->i_blkbits, dun);
+	fscrypt_generate_dun(ci, pos, dun);
 	bio_crypt_set_ctx(bio, ci->ci_enc_key.blk_key, dun, gfp_mask);
 }
 EXPORT_SYMBOL_GPL(fscrypt_set_bio_crypt_ctx);
diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 5df5e7e6adde..2c776af75916 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -428,9 +428,7 @@ static void io_submit_init_bio(struct ext4_io_submit *io,
 	 */
 	bio = bio_alloc(bh->b_bdev, BIO_MAX_VECS, REQ_OP_WRITE, GFP_NOIO);
 	fscrypt_set_bio_crypt_ctx(bio, inode,
-			(folio_pos(io_folio) + bh_offset(bh)) >>
-				inode->i_blkbits,
-			GFP_NOIO);
+			folio_pos(io_folio) + bh_offset(bh), GFP_NOIO);
 	bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9);
 	bio->bi_end_io = ext4_end_bio;
 	bio->bi_private = ext4_get_io_end(io->io_end);
diff --git a/fs/ext4/readpage.c b/fs/ext4/readpage.c
index ba7cfddd6038..fbfa4d830d9a 100644
--- a/fs/ext4/readpage.c
+++ b/fs/ext4/readpage.c
@@ -355,8 +355,8 @@ static int ext4_mpage_readpages(struct inode *inode, struct fsverity_info *vi,
 			 */
 			bio = bio_alloc(bdev, bio_max_segs(nr_pages),
 					REQ_OP_READ, GFP_KERNEL);
-			fscrypt_set_bio_crypt_ctx(bio, inode, next_block,
-						  GFP_KERNEL);
+			fscrypt_set_bio_crypt_ctx(bio, inode,
+					(loff_t)next_block << blkbits, GFP_KERNEL);
 			ext4_set_bio_post_read_ctx(bio, inode, vi);
 			bio->bi_iter.bi_sector = first_block << (blkbits - 9);
 			bio->bi_end_io = mpage_end_io;
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index dca273fedfde..07b4ed6bb0cc 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -527,7 +527,9 @@ static void f2fs_set_bio_crypt_ctx(struct bio *bio, const struct inode *inode,
 	 * read/write raw data without encryption.
 	 */
 	if (!fio || !fio->encrypted_page)
-		fscrypt_set_bio_crypt_ctx(bio, inode, first_idx, gfp_mask);
+		fscrypt_set_bio_crypt_ctx(bio, inode,
+				(loff_t)first_idx << inode->i_blkbits,
+				gfp_mask);
 }
 
 static bool f2fs_crypt_mergeable_bio(struct bio *bio, const struct inode *inode,
diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
index 95254aa1b654..b4ee4465f4db 100644
--- a/fs/iomap/direct-io.c
+++ b/fs/iomap/direct-io.c
@@ -298,8 +298,7 @@ static int iomap_dio_zero(const struct iomap_iter *iter, struct iomap_dio *dio,
 
 	bio = iomap_dio_alloc_bio(iter, dio, nr_vecs,
 				  REQ_OP_WRITE | REQ_SYNC | REQ_IDLE);
-	fscrypt_set_bio_crypt_ctx(bio, inode, pos >> inode->i_blkbits,
-				  GFP_KERNEL);
+	fscrypt_set_bio_crypt_ctx(bio, inode, pos, GFP_KERNEL);
 	bio->bi_iter.bi_sector = iomap_sector(&iter->iomap, pos);
 	bio->bi_private = dio;
 	bio->bi_end_io = iomap_dio_bio_end_io;
@@ -329,8 +328,7 @@ static ssize_t iomap_dio_bio_iter_one(struct iomap_iter *iter,
 		nr_vecs = bio_iov_vecs_to_alloc(dio->submit.iter, BIO_MAX_VECS);
 
 	bio = iomap_dio_alloc_bio(iter, dio, nr_vecs, op);
-	fscrypt_set_bio_crypt_ctx(bio, iter->inode,
-			pos >> iter->inode->i_blkbits, GFP_KERNEL);
+	fscrypt_set_bio_crypt_ctx(bio, iter->inode, pos, GFP_KERNEL);
 	bio->bi_iter.bi_sector = iomap_sector(&iter->iomap, pos);
 	bio->bi_write_hint = iter->inode->i_write_hint;
 	bio->bi_ioprio = dio->iocb->ki_ioprio;
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 98fb14660d40..90f75fe0e1c9 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -865,9 +865,8 @@ static inline void fscrypt_set_ops(struct super_block *sb,
 
 bool __fscrypt_inode_uses_inline_crypto(const struct inode *inode);
 
-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(struct bio *bio, const struct inode *inode,
+			       loff_t pos, gfp_t gfp_mask);
 
 bool fscrypt_mergeable_bio(struct bio *bio, const struct inode *inode,
 			   loff_t pos);
@@ -885,7 +884,7 @@ static inline bool __fscrypt_inode_uses_inline_crypto(const struct inode *inode)
 
 static inline void fscrypt_set_bio_crypt_ctx(struct bio *bio,
 					     const struct inode *inode,
-					     u64 first_lblk, gfp_t gfp_mask) { }
+					     loff_t pos, gfp_t gfp_mask) { }
 
 static inline bool fscrypt_mergeable_bio(struct bio *bio,
 					 const struct inode *inode,
-- 
2.47.3

[PATCH 09/14] fscrypt: pass a byte offset to fscrypt_zeroout_range_inline_crypt

[Christoph Hellwig]

Logical offsets into an inode are usually expressed as bytes in the VFS.
Switch fscrypt_zeroout_range_inline_crypt to that convention.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/crypto/bio.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/crypto/bio.c b/fs/crypto/bio.c
index e7fb2fdd9728..7558b3e69701 100644
--- a/fs/crypto/bio.c
+++ b/fs/crypto/bio.c
@@ -70,12 +70,11 @@ static void fscrypt_zeroout_range_end_io(struct bio *bio)
 }
 
 static int fscrypt_zeroout_range_inline_crypt(const struct inode *inode,
-					      pgoff_t lblk, sector_t sector,
+					      loff_t pos, sector_t sector,
 					      unsigned int len)
 {
 	const unsigned int blockbits = inode->i_blkbits;
 	const unsigned int blocks_per_page = 1 << (PAGE_SHIFT - blockbits);
-	loff_t pos = (loff_t)lblk << blockbits;
 	struct fscrypt_zero_done done = {
 		.pending	= ATOMIC_INIT(1),
 		.done		= COMPLETION_INITIALIZER_ONSTACK(done.done),
@@ -142,6 +141,7 @@ int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk,
 	const unsigned int du_per_page = 1U << du_per_page_bits;
 	u64 du_index = (u64)lblk << (inode->i_blkbits - du_bits);
 	u64 du_remaining = (u64)len << (inode->i_blkbits - du_bits);
+	loff_t pos = (loff_t)lblk << inode->i_blkbits;
 	sector_t sector = pblk << (inode->i_blkbits - SECTOR_SHIFT);
 	struct page *pages[16]; /* write up to 16 pages at a time */
 	unsigned int nr_pages;
@@ -154,7 +154,7 @@ int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk,
 		return 0;
 
 	if (fscrypt_inode_uses_inline_crypto(inode))
-		return fscrypt_zeroout_range_inline_crypt(inode, lblk, sector,
+		return fscrypt_zeroout_range_inline_crypt(inode, pos, sector,
 							  len);
 
 	BUILD_BUG_ON(ARRAY_SIZE(pages) > BIO_MAX_VECS);
-- 
2.47.3

[PATCH 10/14] fscrypt: pass a byte length to fscrypt_zeroout_range_inline_crypt

[Christoph Hellwig]

Range lengths are usually expressed as bytes in the VFS, switch
fscrypt_zeroout_range_inline_crypt to this convention.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/crypto/bio.c | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/fs/crypto/bio.c b/fs/crypto/bio.c
index 7558b3e69701..36025ce7a264 100644
--- a/fs/crypto/bio.c
+++ b/fs/crypto/bio.c
@@ -73,8 +73,6 @@ static int fscrypt_zeroout_range_inline_crypt(const struct inode *inode,
 					      loff_t pos, sector_t sector,
 					      unsigned int len)
 {
-	const unsigned int blockbits = inode->i_blkbits;
-	const unsigned int blocks_per_page = 1 << (PAGE_SHIFT - blockbits);
 	struct fscrypt_zero_done done = {
 		.pending	= ATOMIC_INIT(1),
 		.done		= COMPLETION_INITIALIZER_ONSTACK(done.done),
@@ -92,12 +90,10 @@ static int fscrypt_zeroout_range_inline_crypt(const struct inode *inode,
 		fscrypt_set_bio_crypt_ctx(bio, inode, pos, GFP_NOFS);
 
 		for (n = 0; n < BIO_MAX_VECS; n++) {
-			unsigned int blocks_this_page =
-				min(len, blocks_per_page);
-			unsigned int bytes_this_page = blocks_this_page << blockbits;
+			unsigned int bytes_this_page = min(len, PAGE_SIZE);
 
 			__bio_add_page(bio, ZERO_PAGE(0), bytes_this_page, 0);
-			len -= blocks_this_page;
+			len -= bytes_this_page;
 			pos += bytes_this_page;
 			sector += (bytes_this_page >> SECTOR_SHIFT);
 			if (!len || !fscrypt_mergeable_bio(bio, inode, pos))
@@ -155,7 +151,7 @@ int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk,
 
 	if (fscrypt_inode_uses_inline_crypto(inode))
 		return fscrypt_zeroout_range_inline_crypt(inode, pos, sector,
-							  len);
+				len << inode->i_blkbits);
 
 	BUILD_BUG_ON(ARRAY_SIZE(pages) > BIO_MAX_VECS);
 	nr_pages = min_t(u64, ARRAY_SIZE(pages),
-- 
2.47.3

[PATCH 11/14] fscrypt: pass a byte offset to fscrypt_zeroout_range

[Christoph Hellwig]

Logical offsets into an inode are usually expressed as bytes in the VFS.
Switch fscrypt_zeroout_range to that convention.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/crypto/bio.c         | 7 +++----
 fs/ext4/inode.c         | 3 ++-
 fs/f2fs/file.c          | 4 +++-
 include/linux/fscrypt.h | 4 ++--
 4 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/fs/crypto/bio.c b/fs/crypto/bio.c
index 36025ce7a264..a4f4ee86c573 100644
--- a/fs/crypto/bio.c
+++ b/fs/crypto/bio.c
@@ -113,7 +113,7 @@ static int fscrypt_zeroout_range_inline_crypt(const struct inode *inode,
 /**
  * fscrypt_zeroout_range() - zero out a range of blocks in an encrypted file
  * @inode: the file's inode
- * @lblk: the first file logical block to zero out
+ * @pos: the first file position (in bytes) to zero out
  * @pblk: the first filesystem physical block to zero out
  * @len: number of blocks to zero out
  *
@@ -127,7 +127,7 @@ static int fscrypt_zeroout_range_inline_crypt(const struct inode *inode,
  *
  * Return: 0 on success; -errno on failure.
  */
-int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk,
+int fscrypt_zeroout_range(const struct inode *inode, loff_t pos,
 			  sector_t pblk, unsigned int len)
 {
 	const struct fscrypt_inode_info *ci = fscrypt_get_inode_info_raw(inode);
@@ -135,9 +135,8 @@ int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk,
 	const unsigned int du_size = 1U << du_bits;
 	const unsigned int du_per_page_bits = PAGE_SHIFT - du_bits;
 	const unsigned int du_per_page = 1U << du_per_page_bits;
-	u64 du_index = (u64)lblk << (inode->i_blkbits - du_bits);
+	u64 du_index = pos >> du_bits;
 	u64 du_remaining = (u64)len << (inode->i_blkbits - du_bits);
-	loff_t pos = (loff_t)lblk << inode->i_blkbits;
 	sector_t sector = pblk << (inode->i_blkbits - SECTOR_SHIFT);
 	struct page *pages[16]; /* write up to 16 pages at a time */
 	unsigned int nr_pages;
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 396dc3a5d16b..945613c95ffa 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -405,7 +405,8 @@ int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk, ext4_fsblk_t pblk,
 	KUNIT_STATIC_STUB_REDIRECT(ext4_issue_zeroout, inode, lblk, pblk, len);
 
 	if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode))
-		return fscrypt_zeroout_range(inode, lblk, pblk, len);
+		return fscrypt_zeroout_range(inode,
+				(loff_t)lblk << inode->i_blkbits, pblk, len);
 
 	ret = sb_issue_zeroout(inode->i_sb, pblk, len, GFP_NOFS);
 	if (ret > 0)
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index c8a2f17a8f11..239c2666ceb5 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -4162,7 +4162,9 @@ static int f2fs_secure_erase(struct block_device *bdev, struct inode *inode,
 
 	if (!ret && (flags & F2FS_TRIM_FILE_ZEROOUT)) {
 		if (IS_ENCRYPTED(inode))
-			ret = fscrypt_zeroout_range(inode, off, block, len);
+			ret = fscrypt_zeroout_range(inode,
+					(loff_t)off << inode->i_blkbits, block,
+					len);
 		else
 			ret = blkdev_issue_zeroout(bdev, sector, nr_sects,
 					GFP_NOFS, 0);
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 90f75fe0e1c9..9fc15e1fbe57 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -450,7 +450,7 @@ u64 fscrypt_fname_siphash(const struct inode *dir, const struct qstr *name);
 
 /* bio.c */
 bool fscrypt_decrypt_bio(struct bio *bio);
-int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk,
+int fscrypt_zeroout_range(const struct inode *inode, loff_t pos,
 			  sector_t pblk, unsigned int len);
 
 /* hooks.c */
@@ -755,7 +755,7 @@ static inline bool fscrypt_decrypt_bio(struct bio *bio)
 	return true;
 }
 
-static inline int fscrypt_zeroout_range(const struct inode *inode, pgoff_t lblk,
+static inline int fscrypt_zeroout_range(const struct inode *inode, loff_t pos,
 					sector_t pblk, unsigned int len)
 {
 	return -EOPNOTSUPP;
-- 
2.47.3

[PATCH 12/14] fscrypt: pass a byte length to fscrypt_zeroout_range

[Christoph Hellwig]

Range lengths are usually expressed as bytes in the VFS, switch
fscrypt_zeroout_range to this convention.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/crypto/bio.c         | 10 +++++-----
 fs/ext4/inode.c         |  3 ++-
 fs/f2fs/file.c          |  2 +-
 include/linux/fscrypt.h |  6 +++---
 4 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/fs/crypto/bio.c b/fs/crypto/bio.c
index a4f4ee86c573..7d57ffb1e8c6 100644
--- a/fs/crypto/bio.c
+++ b/fs/crypto/bio.c
@@ -71,7 +71,7 @@ static void fscrypt_zeroout_range_end_io(struct bio *bio)
 
 static int fscrypt_zeroout_range_inline_crypt(const struct inode *inode,
 					      loff_t pos, sector_t sector,
-					      unsigned int len)
+					      u64 len)
 {
 	struct fscrypt_zero_done done = {
 		.pending	= ATOMIC_INIT(1),
@@ -115,7 +115,7 @@ static int fscrypt_zeroout_range_inline_crypt(const struct inode *inode,
  * @inode: the file's inode
  * @pos: the first file position (in bytes) to zero out
  * @pblk: the first filesystem physical block to zero out
- * @len: number of blocks to zero out
+ * @len: bytes to zero out
  *
  * Zero out filesystem blocks in an encrypted regular file on-disk, i.e. write
  * ciphertext blocks which decrypt to the all-zeroes block.  The blocks must be
@@ -128,7 +128,7 @@ static int fscrypt_zeroout_range_inline_crypt(const struct inode *inode,
  * Return: 0 on success; -errno on failure.
  */
 int fscrypt_zeroout_range(const struct inode *inode, loff_t pos,
-			  sector_t pblk, unsigned int len)
+			  sector_t pblk, u64 len)
 {
 	const struct fscrypt_inode_info *ci = fscrypt_get_inode_info_raw(inode);
 	const unsigned int du_bits = ci->ci_data_unit_bits;
@@ -136,7 +136,7 @@ int fscrypt_zeroout_range(const struct inode *inode, loff_t pos,
 	const unsigned int du_per_page_bits = PAGE_SHIFT - du_bits;
 	const unsigned int du_per_page = 1U << du_per_page_bits;
 	u64 du_index = pos >> du_bits;
-	u64 du_remaining = (u64)len << (inode->i_blkbits - du_bits);
+	u64 du_remaining = len >> du_bits;
 	sector_t sector = pblk << (inode->i_blkbits - SECTOR_SHIFT);
 	struct page *pages[16]; /* write up to 16 pages at a time */
 	unsigned int nr_pages;
@@ -150,7 +150,7 @@ int fscrypt_zeroout_range(const struct inode *inode, loff_t pos,
 
 	if (fscrypt_inode_uses_inline_crypto(inode))
 		return fscrypt_zeroout_range_inline_crypt(inode, pos, sector,
-				len << inode->i_blkbits);
+				len);
 
 	BUILD_BUG_ON(ARRAY_SIZE(pages) > BIO_MAX_VECS);
 	nr_pages = min_t(u64, ARRAY_SIZE(pages),
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 945613c95ffa..675ef741cb30 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -406,7 +406,8 @@ int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk, ext4_fsblk_t pblk,
 
 	if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode))
 		return fscrypt_zeroout_range(inode,
-				(loff_t)lblk << inode->i_blkbits, pblk, len);
+				(loff_t)lblk << inode->i_blkbits, pblk,
+				len << inode->i_blkbits);
 
 	ret = sb_issue_zeroout(inode->i_sb, pblk, len, GFP_NOFS);
 	if (ret > 0)
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 239c2666ceb5..5b7013f7f6a1 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -4164,7 +4164,7 @@ static int f2fs_secure_erase(struct block_device *bdev, struct inode *inode,
 		if (IS_ENCRYPTED(inode))
 			ret = fscrypt_zeroout_range(inode,
 					(loff_t)off << inode->i_blkbits, block,
-					len);
+					len << inode->i_blkbits);
 		else
 			ret = blkdev_issue_zeroout(bdev, sector, nr_sects,
 					GFP_NOFS, 0);
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 9fc15e1fbe57..90ac62fda926 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -450,8 +450,8 @@ u64 fscrypt_fname_siphash(const struct inode *dir, const struct qstr *name);
 
 /* bio.c */
 bool fscrypt_decrypt_bio(struct bio *bio);
-int fscrypt_zeroout_range(const struct inode *inode, loff_t pos,
-			  sector_t pblk, unsigned int len);
+int fscrypt_zeroout_range(const struct inode *inode, loff_t pos, sector_t pblk,
+			  u64 len);
 
 /* hooks.c */
 int fscrypt_file_open(struct inode *inode, struct file *filp);
@@ -756,7 +756,7 @@ static inline bool fscrypt_decrypt_bio(struct bio *bio)
 }
 
 static inline int fscrypt_zeroout_range(const struct inode *inode, loff_t pos,
-					sector_t pblk, unsigned int len)
+					sector_t pblk, u64 len)
 {
 	return -EOPNOTSUPP;
 }
-- 
2.47.3

Re: [PATCH 12/14] fscrypt: pass a byte length to fscrypt_zeroout_range

[Eric Biggers]

On Thu, Feb 26, 2026 at 06:49:32AM -0800, Christoph Hellwig wrote:
>  static int fscrypt_zeroout_range_inline_crypt(const struct inode *inode,
>  					      loff_t pos, sector_t sector,
> -					      unsigned int len)
> +					      u64 len)

This hunk should go in the "pass a byte length to
fscrypt_zeroout_range_inline_crypt" patch.

>   * @inode: the file's inode
>   * @pos: the first file position (in bytes) to zero out
>   * @pblk: the first filesystem physical block to zero out
> - * @len: number of blocks to zero out
> + * @len: bytes to zero out

Should document that 'len' must be a multiple of the filesystem block
size

> diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> index 945613c95ffa..675ef741cb30 100644
> --- a/fs/ext4/inode.c
> +++ b/fs/ext4/inode.c
> @@ -406,7 +406,8 @@ int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk, ext4_fsblk_t pblk,
>  
>  	if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode))
>  		return fscrypt_zeroout_range(inode,
> -				(loff_t)lblk << inode->i_blkbits, pblk, len);
> +				(loff_t)lblk << inode->i_blkbits, pblk,
> +				len << inode->i_blkbits);
>  
>  	ret = sb_issue_zeroout(inode->i_sb, pblk, len, GFP_NOFS);
>  	if (ret > 0)
> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> index 239c2666ceb5..5b7013f7f6a1 100644
> --- a/fs/f2fs/file.c
> +++ b/fs/f2fs/file.c
> @@ -4164,7 +4164,7 @@ static int f2fs_secure_erase(struct block_device *bdev, struct inode *inode,
>  		if (IS_ENCRYPTED(inode))
>  			ret = fscrypt_zeroout_range(inode,
>  					(loff_t)off << inode->i_blkbits, block,
> -					len);
> +					len << inode->i_blkbits);

The two callers should cast len to u64 before shifting it by i_blkbits.

- Eric

[PATCH 13/14] fscrypt: pass a real sector_t to fscrypt_zeroout_range

[Christoph Hellwig]

While the pblk argument to fscrypt_zeroout_range is declared as a
sector_t, it actually is interpreted as a logical block size unit, which
is highly unusual.  Switch to passing the 512 byte units that sector_t is
defined for.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/crypto/bio.c         | 5 ++---
 fs/ext4/inode.c         | 3 ++-
 fs/f2fs/file.c          | 2 +-
 include/linux/fscrypt.h | 6 +++---
 4 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/fs/crypto/bio.c b/fs/crypto/bio.c
index 7d57ffb1e8c6..4a45bd28e0da 100644
--- a/fs/crypto/bio.c
+++ b/fs/crypto/bio.c
@@ -114,7 +114,7 @@ static int fscrypt_zeroout_range_inline_crypt(const struct inode *inode,
  * fscrypt_zeroout_range() - zero out a range of blocks in an encrypted file
  * @inode: the file's inode
  * @pos: the first file position (in bytes) to zero out
- * @pblk: the first filesystem physical block to zero out
+ * @sector: the first sector to zero out
  * @len: bytes to zero out
  *
  * Zero out filesystem blocks in an encrypted regular file on-disk, i.e. write
@@ -128,7 +128,7 @@ static int fscrypt_zeroout_range_inline_crypt(const struct inode *inode,
  * Return: 0 on success; -errno on failure.
  */
 int fscrypt_zeroout_range(const struct inode *inode, loff_t pos,
-			  sector_t pblk, u64 len)
+			  sector_t sector, u64 len)
 {
 	const struct fscrypt_inode_info *ci = fscrypt_get_inode_info_raw(inode);
 	const unsigned int du_bits = ci->ci_data_unit_bits;
@@ -137,7 +137,6 @@ int fscrypt_zeroout_range(const struct inode *inode, loff_t pos,
 	const unsigned int du_per_page = 1U << du_per_page_bits;
 	u64 du_index = pos >> du_bits;
 	u64 du_remaining = len >> du_bits;
-	sector_t sector = pblk << (inode->i_blkbits - SECTOR_SHIFT);
 	struct page *pages[16]; /* write up to 16 pages at a time */
 	unsigned int nr_pages;
 	unsigned int i;
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 675ef741cb30..d0028d6d3de1 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -406,7 +406,8 @@ int ext4_issue_zeroout(struct inode *inode, ext4_lblk_t lblk, ext4_fsblk_t pblk,
 
 	if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode))
 		return fscrypt_zeroout_range(inode,
-				(loff_t)lblk << inode->i_blkbits, pblk,
+				(loff_t)lblk << inode->i_blkbits,
+				pblk << (inode->i_blkbits - SECTOR_SHIFT),
 				len << inode->i_blkbits);
 
 	ret = sb_issue_zeroout(inode->i_sb, pblk, len, GFP_NOFS);
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 5b7013f7f6a1..ad435dea656a 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -4163,7 +4163,7 @@ static int f2fs_secure_erase(struct block_device *bdev, struct inode *inode,
 	if (!ret && (flags & F2FS_TRIM_FILE_ZEROOUT)) {
 		if (IS_ENCRYPTED(inode))
 			ret = fscrypt_zeroout_range(inode,
-					(loff_t)off << inode->i_blkbits, block,
+					(loff_t)off << inode->i_blkbits, sector,
 					len << inode->i_blkbits);
 		else
 			ret = blkdev_issue_zeroout(bdev, sector, nr_sects,
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 90ac62fda926..54712ec61ffb 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -450,8 +450,8 @@ u64 fscrypt_fname_siphash(const struct inode *dir, const struct qstr *name);
 
 /* bio.c */
 bool fscrypt_decrypt_bio(struct bio *bio);
-int fscrypt_zeroout_range(const struct inode *inode, loff_t pos, sector_t pblk,
-			  u64 len);
+int fscrypt_zeroout_range(const struct inode *inode, loff_t pos,
+			  sector_t sector, u64 len);
 
 /* hooks.c */
 int fscrypt_file_open(struct inode *inode, struct file *filp);
@@ -756,7 +756,7 @@ static inline bool fscrypt_decrypt_bio(struct bio *bio)
 }
 
 static inline int fscrypt_zeroout_range(const struct inode *inode, loff_t pos,
-					sector_t pblk, u64 len)
+					sector_t sector, u64 len)
 {
 	return -EOPNOTSUPP;
 }
-- 
2.47.3

[PATCH 14/14] ext4: use a byte granularity cursor in ext4_mpage_readpages

[Christoph Hellwig]

Replace the next_block variable that is in units of file system blocks
and incorretly uses the sector_t type with a byte offset, as that is
what both users want.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/ext4/readpage.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/fs/ext4/readpage.c b/fs/ext4/readpage.c
index fbfa4d830d9a..c94240c91282 100644
--- a/fs/ext4/readpage.c
+++ b/fs/ext4/readpage.c
@@ -215,11 +215,11 @@ static int ext4_mpage_readpages(struct inode *inode, struct fsverity_info *vi,
 	sector_t last_block_in_bio = 0;
 	const unsigned blkbits = inode->i_blkbits;
 	const unsigned blocksize = 1 << blkbits;
-	sector_t next_block;
 	sector_t block_in_file;
 	sector_t last_block;
 	sector_t last_block_in_file;
 	sector_t first_block;
+	loff_t pos;
 	unsigned page_block;
 	struct block_device *bdev = inode->i_sb->s_bdev;
 	int length;
@@ -249,7 +249,8 @@ static int ext4_mpage_readpages(struct inode *inode, struct fsverity_info *vi,
 
 		blocks_per_folio = folio_size(folio) >> blkbits;
 		first_hole = blocks_per_folio;
-		block_in_file = next_block = EXT4_PG_TO_LBLK(inode, folio->index);
+		block_in_file = EXT4_PG_TO_LBLK(inode, folio->index);
+		pos = (loff_t)block_in_file << blkbits;
 		last_block = EXT4_PG_TO_LBLK(inode, folio->index + nr_pages);
 		last_block_in_file = (ext4_readpage_limit(inode) +
 				      blocksize - 1) >> blkbits;
@@ -342,8 +343,7 @@ static int ext4_mpage_readpages(struct inode *inode, struct fsverity_info *vi,
 		 * BIO off first?
 		 */
 		if (bio && (last_block_in_bio != first_block - 1 ||
-			    !fscrypt_mergeable_bio(bio, inode,
-				(loff_t)next_block << blkbits))) {
+			    !fscrypt_mergeable_bio(bio, inode, pos))) {
 		submit_and_realloc:
 			blk_crypto_submit_bio(bio);
 			bio = NULL;
@@ -355,8 +355,7 @@ static int ext4_mpage_readpages(struct inode *inode, struct fsverity_info *vi,
 			 */
 			bio = bio_alloc(bdev, bio_max_segs(nr_pages),
 					REQ_OP_READ, GFP_KERNEL);
-			fscrypt_set_bio_crypt_ctx(bio, inode,
-					(loff_t)next_block << blkbits, GFP_KERNEL);
+			fscrypt_set_bio_crypt_ctx(bio, inode, pos, GFP_KERNEL);
 			ext4_set_bio_post_read_ctx(bio, inode, vi);
 			bio->bi_iter.bi_sector = first_block << (blkbits - 9);
 			bio->bi_end_io = mpage_end_io;
-- 
2.47.3

Re: [PATCH 14/14] ext4: use a byte granularity cursor in ext4_mpage_readpages

[Eric Biggers]

On Thu, Feb 26, 2026 at 06:49:34AM -0800, Christoph Hellwig wrote:
> +		block_in_file = EXT4_PG_TO_LBLK(inode, folio->index);
> +		pos = (loff_t)block_in_file << blkbits;

The EXT4_PG_TO_LBLK() expands to:

        (((loff_t)(folio->index) << PAGE_SHIFT) >> (inode)->i_blkbits)

So it calculates the pos as an intermediate step, and we end up with the
redundant pos = (pos >> blkbits) << blkbits.

It probably would make more sense to calculate the pos first, similar to
what other places in this series do:

        pos = folio_pos(folio);                                          
        block_in_file = pos >> blkbits;

- Eric

fscrypt API cleanups v3

[Christoph Hellwig]

Hi all,

this series cleans up various fscrypt APIs to pass logical offsets in
and lengths in bytes, and on-disk sectors as 512-byte sector units,
like most of the VFS and block code.

Changes since v2:
 - use the local bio variable in io_submit_init_bio
 - use folio instead of io_folio (and actually test the noinline mode,
   which should have cought this for the last round)
 - add an extra IS_ENABLED(CONFIG_FS_ENCRYPTION) to safeguard
   against potentially stupid compilers
 - document the byte length needs to be a multiple of the block
   size
 - case to u64 when passing the byte length
 - move a hunk to an earlier patch
Changes since v1:
 - remove all buffer_head helpers, and do that before the API cleanups
   to simplify the series
 - fix a bisection hazard
 - spelling fixes in the commit logs
 - use "file position" to describe the byte offset into an inode
 - add another small ext4 cleanup at the end

Diffstat:
 fs/buffer.c                 |   18 ++++++++-
 fs/crypto/bio.c             |   40 +++++++++-----------
 fs/crypto/fscrypt_private.h |    3 -
 fs/crypto/inline_crypt.c    |   86 ++++----------------------------------------
 fs/crypto/keysetup.c        |    2 -
 fs/ext4/inode.c             |    5 ++
 fs/ext4/page-io.c           |   28 ++++++++++----
 fs/ext4/readpage.c          |   10 ++---
 fs/f2fs/data.c              |    7 ++-
 fs/f2fs/file.c              |    4 +-
 fs/iomap/direct-io.c        |    6 +--
 include/linux/fscrypt.h     |   37 ++++--------------
 12 files changed, 92 insertions(+), 154 deletions(-)

[PATCH 04/14] ext4, fscrypt: merge fscrypt_mergeable_bio_bh into io_submit_need_new_bio

[Christoph Hellwig]

ext4 already has the inode and folio and can't have a NULL
folio->mapping in this path. Open code fscrypt_mergeable_bio_bh in
io_submit_need_new_bio based on these simplifying assumptions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/crypto/inline_crypt.c | 23 -----------------------
 fs/ext4/page-io.c        |  7 +++++--
 include/linux/fscrypt.h  |  9 ---------
 3 files changed, 5 insertions(+), 34 deletions(-)

diff --git a/fs/crypto/inline_crypt.c b/fs/crypto/inline_crypt.c
index c0852b920dbc..0da53956a9b1 100644
--- a/fs/crypto/inline_crypt.c
+++ b/fs/crypto/inline_crypt.c
@@ -406,29 +406,6 @@ bool fscrypt_mergeable_bio(struct bio *bio, const struct inode *inode,
 }
 EXPORT_SYMBOL_GPL(fscrypt_mergeable_bio);
 
-/**
- * fscrypt_mergeable_bio_bh() - test whether data can be added to a bio
- * @bio: the bio being built up
- * @next_bh: the next buffer_head for which I/O will be submitted
- *
- * Same as fscrypt_mergeable_bio(), except this takes a buffer_head instead of
- * an inode and block number directly.
- *
- * Return: true iff the I/O is mergeable
- */
-bool fscrypt_mergeable_bio_bh(struct bio *bio,
-			      const struct buffer_head *next_bh)
-{
-	const struct inode *inode;
-	u64 next_lblk;
-
-	if (!bh_get_inode_and_lblk_num(next_bh, &inode, &next_lblk))
-		return !bio->bi_crypt_context;
-
-	return fscrypt_mergeable_bio(bio, inode, next_lblk);
-}
-EXPORT_SYMBOL_GPL(fscrypt_mergeable_bio_bh);
-
 /**
  * fscrypt_dio_supported() - check whether DIO (direct I/O) is supported on an
  *			     inode, as far as encryption is concerned
diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c
index 58cdbd836fd6..293314d7f236 100644
--- a/fs/ext4/page-io.c
+++ b/fs/ext4/page-io.c
@@ -440,11 +440,14 @@ static void io_submit_init_bio(struct ext4_io_submit *io,
 }
 
 static bool io_submit_need_new_bio(struct ext4_io_submit *io,
+				   struct inode *inode,
+				   struct folio *folio,
 				   struct buffer_head *bh)
 {
 	if (bh->b_blocknr != io->io_next_block)
 		return true;
-	if (!fscrypt_mergeable_bio_bh(io->io_bio, bh))
+	if (!fscrypt_mergeable_bio(io->io_bio, inode,
+			(folio_pos(folio) + bh_offset(bh)) >> inode->i_blkbits))
 		return true;
 	return false;
 }
@@ -455,7 +458,7 @@ static void io_submit_add_bh(struct ext4_io_submit *io,
 			     struct folio *io_folio,
 			     struct buffer_head *bh)
 {
-	if (io->io_bio && io_submit_need_new_bio(io, bh)) {
+	if (io->io_bio && io_submit_need_new_bio(io, inode, folio, bh)) {
 submit_and_retry:
 		ext4_io_submit(io);
 	}
diff --git a/include/linux/fscrypt.h b/include/linux/fscrypt.h
index 516aba5b858b..6af3c1907adc 100644
--- a/include/linux/fscrypt.h
+++ b/include/linux/fscrypt.h
@@ -876,9 +876,6 @@ void fscrypt_set_bio_crypt_ctx_bh(struct bio *bio,
 bool fscrypt_mergeable_bio(struct bio *bio, const struct inode *inode,
 			   u64 next_lblk);
 
-bool fscrypt_mergeable_bio_bh(struct bio *bio,
-			      const struct buffer_head *next_bh);
-
 bool fscrypt_dio_supported(struct inode *inode);
 
 u64 fscrypt_limit_io_blocks(const struct inode *inode, u64 lblk, u64 nr_blocks);
@@ -906,12 +903,6 @@ static inline bool fscrypt_mergeable_bio(struct bio *bio,
 	return true;
 }
 
-static inline bool fscrypt_mergeable_bio_bh(struct bio *bio,
-					    const struct buffer_head *next_bh)
-{
-	return true;
-}
-
 static inline bool fscrypt_dio_supported(struct inode *inode)
 {
 	return !fscrypt_needs_contents_encryption(inode);
-- 
2.47.3