* [PATCH v2 1/5] btrfs: unify the ro checking for mount options
2020-09-28 18:34 [PATCH v2 0/5] New rescue mount options Josef Bacik
@ 2020-09-28 18:34 ` Josef Bacik
2020-09-28 18:34 ` [PATCH v2 2/5] btrfs: push the NODATASUM check into btrfs_lookup_bio_sums Josef Bacik
` (4 subsequent siblings)
5 siblings, 0 replies; 9+ messages in thread
From: Josef Bacik @ 2020-09-28 18:34 UTC (permalink / raw)
To: linux-btrfs, kernel-team; +Cc: Qu Wenruo
We're going to be adding more options that require RDONLY, so add a
helper to do the check and error out if we don't have RDONLY set.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
fs/btrfs/super.c | 23 ++++++++++++++++-------
1 file changed, 16 insertions(+), 7 deletions(-)
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 8840a4fa81eb..f99e89ec46b2 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -458,6 +458,17 @@ static const match_table_t rescue_tokens = {
{Opt_err, NULL},
};
+static bool check_ro_option(struct btrfs_fs_info *fs_info, unsigned long opt,
+ const char *opt_name)
+{
+ if (fs_info->mount_opt & opt) {
+ btrfs_err(fs_info, "%s must be used with ro mount option",
+ opt_name);
+ return true;
+ }
+ return false;
+}
+
static int parse_rescue_options(struct btrfs_fs_info *info, const char *options)
{
char *opts;
@@ -968,14 +979,12 @@ int btrfs_parse_options(struct btrfs_fs_info *info, char *options,
}
}
check:
- /*
- * Extra check for current option against current flag
- */
- if (btrfs_test_opt(info, NOLOGREPLAY) && !(new_flags & SB_RDONLY)) {
- btrfs_err(info,
- "nologreplay must be used with ro mount option");
+ /* We're read-only, don't have to check. */
+ if (new_flags & SB_RDONLY)
+ goto out;
+
+ if (check_ro_option(info, BTRFS_MOUNT_NOLOGREPLAY, "nologreplay"))
ret = -EINVAL;
- }
out:
if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE) &&
!btrfs_test_opt(info, FREE_SPACE_TREE) &&
--
2.26.2
^ permalink raw reply related [flat|nested] 9+ messages in thread* [PATCH v2 2/5] btrfs: push the NODATASUM check into btrfs_lookup_bio_sums
2020-09-28 18:34 [PATCH v2 0/5] New rescue mount options Josef Bacik
2020-09-28 18:34 ` [PATCH v2 1/5] btrfs: unify the ro checking for " Josef Bacik
@ 2020-09-28 18:34 ` Josef Bacik
2020-09-28 18:34 ` [PATCH v2 3/5] btrfs: introduce rescue=ignorebadroots Josef Bacik
` (3 subsequent siblings)
5 siblings, 0 replies; 9+ messages in thread
From: Josef Bacik @ 2020-09-28 18:34 UTC (permalink / raw)
To: linux-btrfs, kernel-team; +Cc: Qu Wenruo
When we move to being able to handle NULL csum_roots it'll be cleaner to
just check in btrfs_lookup_bio_sums instead of at all of the caller
locations, so push the NODATASUM check into it as well so it's unified.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
fs/btrfs/compression.c | 14 +++++---------
fs/btrfs/file-item.c | 3 +++
fs/btrfs/inode.c | 12 +++++++++---
3 files changed, 17 insertions(+), 12 deletions(-)
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index eeface30facd..7e1eb57b923c 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -722,11 +722,9 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
*/
refcount_inc(&cb->pending_bios);
- if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
- ret = btrfs_lookup_bio_sums(inode, comp_bio,
- (u64)-1, sums);
- BUG_ON(ret); /* -ENOMEM */
- }
+ ret = btrfs_lookup_bio_sums(inode, comp_bio, (u64)-1,
+ sums);
+ BUG_ON(ret); /* -ENOMEM */
nr_sectors = DIV_ROUND_UP(comp_bio->bi_iter.bi_size,
fs_info->sectorsize);
@@ -751,10 +749,8 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio,
ret = btrfs_bio_wq_end_io(fs_info, comp_bio, BTRFS_WQ_ENDIO_DATA);
BUG_ON(ret); /* -ENOMEM */
- if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
- ret = btrfs_lookup_bio_sums(inode, comp_bio, (u64)-1, sums);
- BUG_ON(ret); /* -ENOMEM */
- }
+ ret = btrfs_lookup_bio_sums(inode, comp_bio, (u64)-1, sums);
+ BUG_ON(ret); /* -ENOMEM */
ret = btrfs_map_bio(fs_info, comp_bio, mirror_num);
if (ret) {
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index 8f4f2bd6d9b9..8083d71d6af6 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -272,6 +272,9 @@ blk_status_t btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio,
int count = 0;
u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+ if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
+ return BLK_STS_OK;
+
path = btrfs_alloc_path();
if (!path)
return BLK_STS_RESOURCE;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index d526833b5ec0..d262944c4297 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2202,7 +2202,12 @@ blk_status_t btrfs_submit_data_bio(struct inode *inode, struct bio *bio,
mirror_num,
bio_flags);
goto out;
- } else if (!skip_sum) {
+ } else {
+ /*
+ * Lookup bio sums does extra checks around whether we
+ * need to csum or not, which is why we ignore skip_sum
+ * here.
+ */
ret = btrfs_lookup_bio_sums(inode, bio, (u64)-1, NULL);
if (ret)
goto out;
@@ -7781,7 +7786,6 @@ static blk_qc_t btrfs_submit_direct(struct inode *inode, struct iomap *iomap,
struct bio *dio_bio, loff_t file_offset)
{
const bool write = (bio_op(dio_bio) == REQ_OP_WRITE);
- const bool csum = !(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM);
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
const bool raid56 = (btrfs_data_alloc_profile(fs_info) &
BTRFS_BLOCK_GROUP_RAID56_MASK);
@@ -7808,10 +7812,12 @@ static blk_qc_t btrfs_submit_direct(struct inode *inode, struct iomap *iomap,
return BLK_QC_T_NONE;
}
- if (!write && csum) {
+ if (!write) {
/*
* Load the csums up front to reduce csum tree searches and
* contention when submitting bios.
+ *
+ * If we have csums disabled this will do nothing.
*/
status = btrfs_lookup_bio_sums(inode, dio_bio, file_offset,
dip->csums);
--
2.26.2
^ permalink raw reply related [flat|nested] 9+ messages in thread* [PATCH v2 3/5] btrfs: introduce rescue=ignorebadroots
2020-09-28 18:34 [PATCH v2 0/5] New rescue mount options Josef Bacik
2020-09-28 18:34 ` [PATCH v2 1/5] btrfs: unify the ro checking for " Josef Bacik
2020-09-28 18:34 ` [PATCH v2 2/5] btrfs: push the NODATASUM check into btrfs_lookup_bio_sums Josef Bacik
@ 2020-09-28 18:34 ` Josef Bacik
2020-09-28 18:34 ` [PATCH v2 4/5] btrfs: introduce rescue=ignoredatacsums Josef Bacik
` (2 subsequent siblings)
5 siblings, 0 replies; 9+ messages in thread
From: Josef Bacik @ 2020-09-28 18:34 UTC (permalink / raw)
To: linux-btrfs, kernel-team
In the face of extent root corruption, or any other core fs wide root
corruption we will fail to mount the file system. This makes recovery
kind of a pain, because you need to fall back to userspace tools to
scrape off data. Instead provide a mechanism to gracefully handle bad
roots, so we can at least mount read-only and possibly recover data from
the file system.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
fs/btrfs/block-group.c | 48 +++++++++++++++++++++++++++++++
fs/btrfs/block-rsv.c | 8 ++++++
fs/btrfs/compression.c | 3 +-
fs/btrfs/ctree.h | 1 +
fs/btrfs/disk-io.c | 65 ++++++++++++++++++++++++++----------------
fs/btrfs/file-item.c | 3 +-
fs/btrfs/inode.c | 6 +++-
fs/btrfs/super.c | 11 ++++++-
fs/btrfs/volumes.c | 13 +++++++++
9 files changed, 130 insertions(+), 28 deletions(-)
diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index c0f1d6818df7..7e32f7820543 100644
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -1985,6 +1985,51 @@ static int read_one_block_group(struct btrfs_fs_info *info,
return ret;
}
+static int fill_dummy_bgs(struct btrfs_fs_info *fs_info)
+{
+ struct extent_map_tree *em_tree = &fs_info->mapping_tree;
+ struct extent_map *em;
+ struct map_lookup *map;
+ struct btrfs_block_group *bg;
+ struct btrfs_space_info *space_info;
+ struct rb_node *node;
+ int ret = 0;
+
+ for (node = rb_first_cached(&em_tree->map); node;
+ node = rb_next(node)) {
+ em = rb_entry(node, struct extent_map, rb_node);
+ map = em->map_lookup;
+ bg = btrfs_create_block_group_cache(fs_info, em->start);
+ if (!bg) {
+ ret = -ENOMEM;
+ break;
+ }
+
+ /* Fill dummy cache as FULL */
+ bg->length = em->len;
+ bg->flags = map->type;
+ bg->last_byte_to_unpin = (u64)-1;
+ bg->cached = BTRFS_CACHE_FINISHED;
+ bg->used = em->len;
+ bg->flags = map->type;
+ ret = btrfs_add_block_group_cache(fs_info, bg);
+ if (ret) {
+ btrfs_remove_free_space_cache(bg);
+ btrfs_put_block_group(bg);
+ break;
+ }
+ btrfs_update_space_info(fs_info, bg->flags, em->len, em->len,
+ 0, &space_info);
+ bg->space_info = space_info;
+ link_block_group(bg);
+
+ set_avail_alloc_bits(fs_info, bg->flags);
+ }
+ if (!ret)
+ btrfs_init_global_block_rsv(fs_info);
+ return ret;
+}
+
int btrfs_read_block_groups(struct btrfs_fs_info *info)
{
struct btrfs_path *path;
@@ -1995,6 +2040,9 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info)
int need_clear = 0;
u64 cache_gen;
+ if (!info->extent_root)
+ return fill_dummy_bgs(info);
+
key.objectid = 0;
key.offset = 0;
key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
diff --git a/fs/btrfs/block-rsv.c b/fs/btrfs/block-rsv.c
index 7e1549a84fcc..58b38912498d 100644
--- a/fs/btrfs/block-rsv.c
+++ b/fs/btrfs/block-rsv.c
@@ -426,6 +426,14 @@ void btrfs_init_global_block_rsv(struct btrfs_fs_info *fs_info)
fs_info->delayed_block_rsv.space_info = space_info;
fs_info->delayed_refs_rsv.space_info = space_info;
+ /*
+ * Our various recovery options can leave us with NULL roots, so check
+ * here and just bail before we go deref'ing NULLS everywhere.
+ */
+ if (!fs_info->extent_root || !fs_info->csum_root ||
+ !fs_info->dev_root || !fs_info->chunk_root || !fs_info->tree_root)
+ return;
+
fs_info->extent_root->block_rsv = &fs_info->delayed_refs_rsv;
fs_info->csum_root->block_rsv = &fs_info->delayed_refs_rsv;
fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 7e1eb57b923c..46dc621f599d 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -150,7 +150,8 @@ static int check_compressed_csum(struct btrfs_inode *inode, struct bio *bio,
struct compressed_bio *cb = bio->bi_private;
u8 *cb_sum = cb->sums;
- if (inode->flags & BTRFS_INODE_NODATASUM)
+ if (!fs_info->csum_root ||
+ inode->flags & BTRFS_INODE_NODATASUM)
return 0;
shash->tfm = fs_info->csum_shash;
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index aac3d6f4e35b..fb3cfd0aaf1e 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1295,6 +1295,7 @@ static inline u32 BTRFS_MAX_XATTR_SIZE(const struct btrfs_fs_info *info)
#define BTRFS_MOUNT_NOLOGREPLAY (1 << 27)
#define BTRFS_MOUNT_REF_VERIFY (1 << 28)
#define BTRFS_MOUNT_DISCARD_ASYNC (1 << 29)
+#define BTRFS_MOUNT_IGNOREBADROOTS (1 << 30)
#define BTRFS_DEFAULT_COMMIT_INTERVAL (30)
#define BTRFS_DEFAULT_MAX_INLINE (2048)
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 3d39f5d47ad3..5deedfb0e5c7 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2247,30 +2247,39 @@ static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
root = btrfs_read_tree_root(tree_root, &location);
if (IS_ERR(root)) {
- ret = PTR_ERR(root);
- goto out;
+ if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
+ ret = PTR_ERR(root);
+ goto out;
+ }
+ } else {
+ set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
+ fs_info->extent_root = root;
}
- set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
- fs_info->extent_root = root;
location.objectid = BTRFS_DEV_TREE_OBJECTID;
root = btrfs_read_tree_root(tree_root, &location);
if (IS_ERR(root)) {
- ret = PTR_ERR(root);
- goto out;
+ if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
+ ret = PTR_ERR(root);
+ goto out;
+ }
+ } else {
+ set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
+ fs_info->dev_root = root;
+ btrfs_init_devices_late(fs_info);
}
- set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
- fs_info->dev_root = root;
- btrfs_init_devices_late(fs_info);
location.objectid = BTRFS_CSUM_TREE_OBJECTID;
root = btrfs_read_tree_root(tree_root, &location);
if (IS_ERR(root)) {
- ret = PTR_ERR(root);
- goto out;
+ if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
+ ret = PTR_ERR(root);
+ goto out;
+ }
+ } else {
+ set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
+ fs_info->csum_root = root;
}
- set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
- fs_info->csum_root = root;
/*
* This tree can share blocks with some other fs tree during relocation
@@ -2279,11 +2288,14 @@ static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
root = btrfs_get_fs_root(tree_root->fs_info,
BTRFS_DATA_RELOC_TREE_OBJECTID, true);
if (IS_ERR(root)) {
- ret = PTR_ERR(root);
- goto out;
+ if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
+ ret = PTR_ERR(root);
+ goto out;
+ }
+ } else {
+ set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
+ fs_info->data_reloc_root = root;
}
- set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
- fs_info->data_reloc_root = root;
location.objectid = BTRFS_QUOTA_TREE_OBJECTID;
root = btrfs_read_tree_root(tree_root, &location);
@@ -2296,9 +2308,11 @@ static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
location.objectid = BTRFS_UUID_TREE_OBJECTID;
root = btrfs_read_tree_root(tree_root, &location);
if (IS_ERR(root)) {
- ret = PTR_ERR(root);
- if (ret != -ENOENT)
- goto out;
+ if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
+ ret = PTR_ERR(root);
+ if (ret != -ENOENT)
+ goto out;
+ }
} else {
set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
fs_info->uuid_root = root;
@@ -2308,11 +2322,14 @@ static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
location.objectid = BTRFS_FREE_SPACE_TREE_OBJECTID;
root = btrfs_read_tree_root(tree_root, &location);
if (IS_ERR(root)) {
- ret = PTR_ERR(root);
- goto out;
+ if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
+ ret = PTR_ERR(root);
+ goto out;
+ }
+ } else {
+ set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
+ fs_info->free_space_root = root;
}
- set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
- fs_info->free_space_root = root;
}
return 0;
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index 8083d71d6af6..90c728652033 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -272,7 +272,8 @@ blk_status_t btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio,
int count = 0;
u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
- if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
+ if (!fs_info->csum_root ||
+ BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
return BLK_STS_OK;
path = btrfs_alloc_path();
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index d262944c4297..27752c66dec4 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2187,7 +2187,8 @@ blk_status_t btrfs_submit_data_bio(struct inode *inode, struct bio *bio,
int skip_sum;
int async = !atomic_read(&BTRFS_I(inode)->sync_writers);
- skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
+ skip_sum = (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM) ||
+ !fs_info->csum_root;
if (btrfs_is_free_space_inode(BTRFS_I(inode)))
metadata = BTRFS_WQ_ENDIO_FREE_SPACE;
@@ -2844,6 +2845,9 @@ int btrfs_verify_data_csum(struct btrfs_io_bio *io_bio, u64 phy_offset,
if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)
return 0;
+ if (!root->fs_info->csum_root)
+ return 0;
+
if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID &&
test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) {
clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM);
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index f99e89ec46b2..7cc7a9233f5e 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -360,6 +360,7 @@ enum {
Opt_rescue,
Opt_usebackuproot,
Opt_nologreplay,
+ Opt_ignorebadroots,
/* Deprecated options */
Opt_recovery,
@@ -455,6 +456,7 @@ static const match_table_t tokens = {
static const match_table_t rescue_tokens = {
{Opt_usebackuproot, "usebackuproot"},
{Opt_nologreplay, "nologreplay"},
+ {Opt_ignorebadroots, "ignorebadroots"},
{Opt_err, NULL},
};
@@ -498,6 +500,10 @@ static int parse_rescue_options(struct btrfs_fs_info *info, const char *options)
btrfs_set_and_info(info, NOLOGREPLAY,
"disabling log replay at mount time");
break;
+ case Opt_ignorebadroots:
+ btrfs_set_and_info(info, IGNOREBADROOTS,
+ "ignoring bad roots");
+ break;
case Opt_err:
btrfs_info(info, "unrecognized rescue option '%s'", p);
ret = -EINVAL;
@@ -983,7 +989,8 @@ int btrfs_parse_options(struct btrfs_fs_info *info, char *options,
if (new_flags & SB_RDONLY)
goto out;
- if (check_ro_option(info, BTRFS_MOUNT_NOLOGREPLAY, "nologreplay"))
+ if (check_ro_option(info, BTRFS_MOUNT_NOLOGREPLAY, "nologreplay") ||
+ check_ro_option(info, BTRFS_MOUNT_IGNOREBADROOTS, "ignorebadroots"))
ret = -EINVAL;
out:
if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE) &&
@@ -1430,6 +1437,8 @@ static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry)
seq_puts(seq, ",notreelog");
if (btrfs_test_opt(info, NOLOGREPLAY))
seq_puts(seq, ",rescue=nologreplay");
+ if (btrfs_test_opt(info, IGNOREBADROOTS))
+ seq_puts(seq, ",rescue=ignorebadroots");
if (btrfs_test_opt(info, FLUSHONCOMMIT))
seq_puts(seq, ",flushoncommit");
if (btrfs_test_opt(info, DISCARD_SYNC))
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 46f4efd58652..f0e6f43a4166 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -7656,6 +7656,19 @@ int btrfs_verify_dev_extents(struct btrfs_fs_info *fs_info)
u64 prev_dev_ext_end = 0;
int ret = 0;
+ /*
+ * We don't have a dev_root because we mounted with ignorebadroots and
+ * failed to load the root, so we want to skip the verification in this
+ * case for sure.
+ *
+ * However if the dev root is fine, but the tree itself is corrupt we'd
+ * still fail to mount. This verification is only to make sure writes
+ * can happen safely, so instead just bypass this check completely in
+ * the case of IGNOREBADROOTS.
+ */
+ if (btrfs_test_opt(fs_info, IGNOREBADROOTS))
+ return 0;
+
key.objectid = 1;
key.type = BTRFS_DEV_EXTENT_KEY;
key.offset = 0;
--
2.26.2
^ permalink raw reply related [flat|nested] 9+ messages in thread* [PATCH v2 4/5] btrfs: introduce rescue=ignoredatacsums
2020-09-28 18:34 [PATCH v2 0/5] New rescue mount options Josef Bacik
` (2 preceding siblings ...)
2020-09-28 18:34 ` [PATCH v2 3/5] btrfs: introduce rescue=ignorebadroots Josef Bacik
@ 2020-09-28 18:34 ` Josef Bacik
2020-09-29 14:57 ` David Sterba
2020-09-28 18:34 ` [PATCH v2 5/5] btrfs: introduce rescue=all Josef Bacik
2020-09-29 15:06 ` [PATCH v2 0/5] New rescue mount options David Sterba
5 siblings, 1 reply; 9+ messages in thread
From: Josef Bacik @ 2020-09-28 18:34 UTC (permalink / raw)
To: linux-btrfs, kernel-team; +Cc: Qu Wenruo
There are cases where you can end up with bad data csums because of
misbehaving applications. This happens when an application modifies a
buffer in-flight when doing an O_DIRECT write. In order to recover the
file we need a way to turn off data checksums so you can copy the file
off, and then you can delete the file and restore it properly later.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
fs/btrfs/ctree.h | 1 +
fs/btrfs/disk-io.c | 21 ++++++++++++---------
fs/btrfs/super.c | 11 ++++++++++-
3 files changed, 23 insertions(+), 10 deletions(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index fb3cfd0aaf1e..397f5f6b88a4 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1296,6 +1296,7 @@ static inline u32 BTRFS_MAX_XATTR_SIZE(const struct btrfs_fs_info *info)
#define BTRFS_MOUNT_REF_VERIFY (1 << 28)
#define BTRFS_MOUNT_DISCARD_ASYNC (1 << 29)
#define BTRFS_MOUNT_IGNOREBADROOTS (1 << 30)
+#define BTRFS_MOUNT_IGNOREDATACSUMS (1 << 31)
#define BTRFS_DEFAULT_COMMIT_INTERVAL (30)
#define BTRFS_DEFAULT_MAX_INLINE (2048)
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 5deedfb0e5c7..6f9d37567a10 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2269,16 +2269,19 @@ static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
btrfs_init_devices_late(fs_info);
}
- location.objectid = BTRFS_CSUM_TREE_OBJECTID;
- root = btrfs_read_tree_root(tree_root, &location);
- if (IS_ERR(root)) {
- if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
- ret = PTR_ERR(root);
- goto out;
+ /* If IGNOREDATASCUMS is set don't bother reading the csum root. */
+ if (!btrfs_test_opt(fs_info, IGNOREDATACSUMS)) {
+ location.objectid = BTRFS_CSUM_TREE_OBJECTID;
+ root = btrfs_read_tree_root(tree_root, &location);
+ if (IS_ERR(root)) {
+ if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
+ ret = PTR_ERR(root);
+ goto out;
+ }
+ } else {
+ set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
+ fs_info->csum_root = root;
}
- } else {
- set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
- fs_info->csum_root = root;
}
/*
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 7cc7a9233f5e..2282f0240c1d 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -361,6 +361,7 @@ enum {
Opt_usebackuproot,
Opt_nologreplay,
Opt_ignorebadroots,
+ Opt_ignoredatacsums,
/* Deprecated options */
Opt_recovery,
@@ -457,6 +458,7 @@ static const match_table_t rescue_tokens = {
{Opt_usebackuproot, "usebackuproot"},
{Opt_nologreplay, "nologreplay"},
{Opt_ignorebadroots, "ignorebadroots"},
+ {Opt_ignoredatacsums, "ignoredatacsums"},
{Opt_err, NULL},
};
@@ -504,6 +506,10 @@ static int parse_rescue_options(struct btrfs_fs_info *info, const char *options)
btrfs_set_and_info(info, IGNOREBADROOTS,
"ignoring bad roots");
break;
+ case Opt_ignoredatacsums:
+ btrfs_set_and_info(info, IGNOREDATACSUMS,
+ "ignoring data csums");
+ break;
case Opt_err:
btrfs_info(info, "unrecognized rescue option '%s'", p);
ret = -EINVAL;
@@ -990,7 +996,10 @@ int btrfs_parse_options(struct btrfs_fs_info *info, char *options,
goto out;
if (check_ro_option(info, BTRFS_MOUNT_NOLOGREPLAY, "nologreplay") ||
- check_ro_option(info, BTRFS_MOUNT_IGNOREBADROOTS, "ignorebadroots"))
+ check_ro_option(info, BTRFS_MOUNT_IGNOREBADROOTS,
+ "ignorebadroots") ||
+ check_ro_option(info, BTRFS_MOUNT_IGNOREDATACSUMS,
+ "ignoredatacsums"))
ret = -EINVAL;
out:
if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE) &&
--
2.26.2
^ permalink raw reply related [flat|nested] 9+ messages in thread* Re: [PATCH v2 4/5] btrfs: introduce rescue=ignoredatacsums
2020-09-28 18:34 ` [PATCH v2 4/5] btrfs: introduce rescue=ignoredatacsums Josef Bacik
@ 2020-09-29 14:57 ` David Sterba
0 siblings, 0 replies; 9+ messages in thread
From: David Sterba @ 2020-09-29 14:57 UTC (permalink / raw)
To: Josef Bacik; +Cc: linux-btrfs, kernel-team, Qu Wenruo
On Mon, Sep 28, 2020 at 02:34:56PM -0400, Josef Bacik wrote:
> There are cases where you can end up with bad data csums because of
> misbehaving applications. This happens when an application modifies a
> buffer in-flight when doing an O_DIRECT write. In order to recover the
> file we need a way to turn off data checksums so you can copy the file
> off, and then you can delete the file and restore it properly later.
>
> Reviewed-by: Qu Wenruo <wqu@suse.com>
> Signed-off-by: Josef Bacik <josef@toxicpanda.com>
> ---
> fs/btrfs/ctree.h | 1 +
> fs/btrfs/disk-io.c | 21 ++++++++++++---------
> fs/btrfs/super.c | 11 ++++++++++-
> 3 files changed, 23 insertions(+), 10 deletions(-)
>
> diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
> index fb3cfd0aaf1e..397f5f6b88a4 100644
> --- a/fs/btrfs/ctree.h
> +++ b/fs/btrfs/ctree.h
> @@ -1296,6 +1296,7 @@ static inline u32 BTRFS_MAX_XATTR_SIZE(const struct btrfs_fs_info *info)
> #define BTRFS_MOUNT_REF_VERIFY (1 << 28)
> #define BTRFS_MOUNT_DISCARD_ASYNC (1 << 29)
> #define BTRFS_MOUNT_IGNOREBADROOTS (1 << 30)
> +#define BTRFS_MOUNT_IGNOREDATACSUMS (1 << 31)
>
> #define BTRFS_DEFAULT_COMMIT_INTERVAL (30)
> #define BTRFS_DEFAULT_MAX_INLINE (2048)
> diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
> index 5deedfb0e5c7..6f9d37567a10 100644
> --- a/fs/btrfs/disk-io.c
> +++ b/fs/btrfs/disk-io.c
> @@ -2269,16 +2269,19 @@ static int btrfs_read_roots(struct btrfs_fs_info *fs_info)
> btrfs_init_devices_late(fs_info);
> }
>
> - location.objectid = BTRFS_CSUM_TREE_OBJECTID;
> - root = btrfs_read_tree_root(tree_root, &location);
> - if (IS_ERR(root)) {
> - if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
> - ret = PTR_ERR(root);
> - goto out;
> + /* If IGNOREDATASCUMS is set don't bother reading the csum root. */
> + if (!btrfs_test_opt(fs_info, IGNOREDATACSUMS)) {
> + location.objectid = BTRFS_CSUM_TREE_OBJECTID;
> + root = btrfs_read_tree_root(tree_root, &location);
> + if (IS_ERR(root)) {
> + if (!btrfs_test_opt(fs_info, IGNOREBADROOTS)) {
> + ret = PTR_ERR(root);
> + goto out;
> + }
> + } else {
> + set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
> + fs_info->csum_root = root;
> }
> - } else {
> - set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state);
> - fs_info->csum_root = root;
> }
>
> /*
> diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
> index 7cc7a9233f5e..2282f0240c1d 100644
> --- a/fs/btrfs/super.c
> +++ b/fs/btrfs/super.c
> @@ -361,6 +361,7 @@ enum {
> Opt_usebackuproot,
> Opt_nologreplay,
> Opt_ignorebadroots,
> + Opt_ignoredatacsums,
>
> /* Deprecated options */
> Opt_recovery,
> @@ -457,6 +458,7 @@ static const match_table_t rescue_tokens = {
> {Opt_usebackuproot, "usebackuproot"},
> {Opt_nologreplay, "nologreplay"},
> {Opt_ignorebadroots, "ignorebadroots"},
> + {Opt_ignoredatacsums, "ignoredatacsums"},
> {Opt_err, NULL},
> };
>
> @@ -504,6 +506,10 @@ static int parse_rescue_options(struct btrfs_fs_info *info, const char *options)
> btrfs_set_and_info(info, IGNOREBADROOTS,
> "ignoring bad roots");
> break;
> + case Opt_ignoredatacsums:
> + btrfs_set_and_info(info, IGNOREDATACSUMS,
> + "ignoring data csums");
> + break;
> case Opt_err:
> btrfs_info(info, "unrecognized rescue option '%s'", p);
> ret = -EINVAL;
> @@ -990,7 +996,10 @@ int btrfs_parse_options(struct btrfs_fs_info *info, char *options,
> goto out;
>
> if (check_ro_option(info, BTRFS_MOUNT_NOLOGREPLAY, "nologreplay") ||
> - check_ro_option(info, BTRFS_MOUNT_IGNOREBADROOTS, "ignorebadroots"))
> + check_ro_option(info, BTRFS_MOUNT_IGNOREBADROOTS,
> + "ignorebadroots") ||
> + check_ro_option(info, BTRFS_MOUNT_IGNOREDATACSUMS,
> + "ignoredatacsums"))
> ret = -EINVAL;
> out:
> if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE) &&
This option is missing in the output of btrfs_show_options, but as there
are going to be several of them the compact format should be used (ie.
the option1:option2:option3).
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH v2 5/5] btrfs: introduce rescue=all
2020-09-28 18:34 [PATCH v2 0/5] New rescue mount options Josef Bacik
` (3 preceding siblings ...)
2020-09-28 18:34 ` [PATCH v2 4/5] btrfs: introduce rescue=ignoredatacsums Josef Bacik
@ 2020-09-28 18:34 ` Josef Bacik
2020-09-29 14:55 ` David Sterba
2020-09-29 15:06 ` [PATCH v2 0/5] New rescue mount options David Sterba
5 siblings, 1 reply; 9+ messages in thread
From: Josef Bacik @ 2020-09-28 18:34 UTC (permalink / raw)
To: linux-btrfs, kernel-team; +Cc: Qu Wenruo
Now that we have the building blocks for some better recovery options
with corrupted file systems, add a rescue=all option to enable all of
the relevant rescue options. This will allow distro's to simply default
to rescue=all for the "oh dear lord the world's on fire" recovery
without needing to know all the different options that we have and may
add in the future.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
fs/btrfs/super.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 2282f0240c1d..3412763a9a0d 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -362,6 +362,7 @@ enum {
Opt_nologreplay,
Opt_ignorebadroots,
Opt_ignoredatacsums,
+ Opt_all,
/* Deprecated options */
Opt_recovery,
@@ -459,6 +460,7 @@ static const match_table_t rescue_tokens = {
{Opt_nologreplay, "nologreplay"},
{Opt_ignorebadroots, "ignorebadroots"},
{Opt_ignoredatacsums, "ignoredatacsums"},
+ {Opt_all, "all"},
{Opt_err, NULL},
};
@@ -510,6 +512,12 @@ static int parse_rescue_options(struct btrfs_fs_info *info, const char *options)
btrfs_set_and_info(info, IGNOREDATACSUMS,
"ignoring data csums");
break;
+ case Opt_all:
+ btrfs_set_opt(info->mount_opt, IGNOREDATACSUMS);
+ btrfs_set_opt(info->mount_opt, IGNOREBADROOTS);
+ btrfs_set_opt(info->mount_opt, NOLOGREPLAY);
+ btrfs_info(info, "enabling all of the rescue options");
+ break;
case Opt_err:
btrfs_info(info, "unrecognized rescue option '%s'", p);
ret = -EINVAL;
--
2.26.2
^ permalink raw reply related [flat|nested] 9+ messages in thread* Re: [PATCH v2 5/5] btrfs: introduce rescue=all
2020-09-28 18:34 ` [PATCH v2 5/5] btrfs: introduce rescue=all Josef Bacik
@ 2020-09-29 14:55 ` David Sterba
0 siblings, 0 replies; 9+ messages in thread
From: David Sterba @ 2020-09-29 14:55 UTC (permalink / raw)
To: Josef Bacik; +Cc: linux-btrfs, kernel-team, Qu Wenruo
On Mon, Sep 28, 2020 at 02:34:57PM -0400, Josef Bacik wrote:
> Now that we have the building blocks for some better recovery options
> with corrupted file systems, add a rescue=all option to enable all of
> the relevant rescue options. This will allow distro's to simply default
> to rescue=all for the "oh dear lord the world's on fire" recovery
> without needing to know all the different options that we have and may
> add in the future.
>
> Reviewed-by: Qu Wenruo <wqu@suse.com>
> Signed-off-by: Josef Bacik <josef@toxicpanda.com>
> ---
> fs/btrfs/super.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
> index 2282f0240c1d..3412763a9a0d 100644
> --- a/fs/btrfs/super.c
> +++ b/fs/btrfs/super.c
> @@ -362,6 +362,7 @@ enum {
> Opt_nologreplay,
> Opt_ignorebadroots,
> Opt_ignoredatacsums,
> + Opt_all,
>
> /* Deprecated options */
> Opt_recovery,
> @@ -459,6 +460,7 @@ static const match_table_t rescue_tokens = {
> {Opt_nologreplay, "nologreplay"},
> {Opt_ignorebadroots, "ignorebadroots"},
> {Opt_ignoredatacsums, "ignoredatacsums"},
> + {Opt_all, "all"},
> {Opt_err, NULL},
> };
>
> @@ -510,6 +512,12 @@ static int parse_rescue_options(struct btrfs_fs_info *info, const char *options)
> btrfs_set_and_info(info, IGNOREDATACSUMS,
> "ignoring data csums");
> break;
> + case Opt_all:
> + btrfs_set_opt(info->mount_opt, IGNOREDATACSUMS);
> + btrfs_set_opt(info->mount_opt, IGNOREBADROOTS);
> + btrfs_set_opt(info->mount_opt, NOLOGREPLAY);
> + btrfs_info(info, "enabling all of the rescue options");
As we're going to add more options in the future, this shoud be more
specific which ones are being enabled under 'all'.
btrfs_info(info, "enabling all default rescue options:");
btrfs_set_opt_and_info(info->mount_opt, IGNOREDATACSUMS, "descripton...");
btrfs_set_opt(info->mount_opt, IGNOREBADROOTS);
btrfs_set_opt(info->mount_opt, NOLOGREPLAY);
Also in sysfs/features we should export all supported rescue options and
which are enabled by all. That's just for user convenience so we don't
have to publish version + supported options separately.
> + break;
> case Opt_err:
> btrfs_info(info, "unrecognized rescue option '%s'", p);
> ret = -EINVAL;
> --
> 2.26.2
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v2 0/5] New rescue mount options
2020-09-28 18:34 [PATCH v2 0/5] New rescue mount options Josef Bacik
` (4 preceding siblings ...)
2020-09-28 18:34 ` [PATCH v2 5/5] btrfs: introduce rescue=all Josef Bacik
@ 2020-09-29 15:06 ` David Sterba
5 siblings, 0 replies; 9+ messages in thread
From: David Sterba @ 2020-09-29 15:06 UTC (permalink / raw)
To: Josef Bacik; +Cc: linux-btrfs, kernel-team
On Mon, Sep 28, 2020 at 02:34:52PM -0400, Josef Bacik wrote:
> And finally we have rescue=all, which simply enables ignoredatacsums,
> ignorebadroots, and notreelogreplay. We need an easy catch-all option for
> distros to fallback on to get users the highest probability of being able to
> recover their data, so we will use rescue=all to turn on all the fanciest rescue
> options that we have, and then use the discrete options for more fine grained
> recovery. Thanks,
>
> Josef
>
> Josef Bacik (5):
> btrfs: unify the ro checking for mount options
> btrfs: push the NODATASUM check into btrfs_lookup_bio_sums
> btrfs: introduce rescue=ignorebadroots
> btrfs: introduce rescue=ignoredatacsums
> btrfs: introduce rescue=all
About the naming, the option names are quite clear but long to type. We
could have shorter aliases, eg. 'ibadroots', where 'i' is short for
'ignore'.
For completeness, we may also want to the negated options or add an
operator that will drop the bit, like
mount -o rescue=all:^ignoredatacsums
mount -o rescue=all,rescue=^ignoredatacsums
^ permalink raw reply [flat|nested] 9+ messages in thread