diff options
| author | Kent Overstreet <kent.overstreet@linux.dev> | 2025-03-24 11:51:01 -0400 |
|---|---|---|
| committer | Kent Overstreet <kent.overstreet@linux.dev> | 2025-03-25 11:49:16 -0400 |
| commit | 3ba0240a8789f8c059990b81c6f34c29769a5a49 (patch) | |
| tree | 56cd7536228392bcc3bfc70916e24e9bb73e01eb | |
| parent | 5af61dbd96275e184adcfe615507b0f04ed7b328 (diff) | |
bcachefs: Fix silent short reads in data read retry path
__bch2_read, before calling __bch2_read_extent(), sets bvec_iter.bi_size
to "the size we can read from the current extent" with a swap, and
restores it to "the size for the total read" after the read_extent call
with another swap.
But we neglected to do the restore before the "if (ret) goto err;" -
which is a problem if we're retrying those errors.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
| -rw-r--r-- | fs/bcachefs/fs-io-buffered.c | 2 | ||||
| -rw-r--r-- | fs/bcachefs/io_read.c | 3 | ||||
| -rw-r--r-- | fs/bcachefs/io_read.h | 6 |
3 files changed, 7 insertions, 4 deletions
diff --git a/fs/bcachefs/fs-io-buffered.c b/fs/bcachefs/fs-io-buffered.c index 5ab1c73c8d4c..a03e2c780cba 100644 --- a/fs/bcachefs/fs-io-buffered.c +++ b/fs/bcachefs/fs-io-buffered.c @@ -225,11 +225,11 @@ static void bchfs_read(struct btree_trans *trans, bch2_read_extent(trans, rbio, iter.pos, data_btree, k, offset_into_extent, flags); + swap(rbio->bio.bi_iter.bi_size, bytes); if (flags & BCH_READ_last_fragment) break; - swap(rbio->bio.bi_iter.bi_size, bytes); bio_advance(&rbio->bio, bytes); err: if (ret && diff --git a/fs/bcachefs/io_read.c b/fs/bcachefs/io_read.c index f1503df57dc7..fafd00a3d6c9 100644 --- a/fs/bcachefs/io_read.c +++ b/fs/bcachefs/io_read.c @@ -1322,13 +1322,14 @@ int __bch2_read(struct btree_trans *trans, struct bch_read_bio *rbio, ret = __bch2_read_extent(trans, rbio, bvec_iter, iter.pos, data_btree, k, offset_into_extent, failed, flags, -1); + swap(bvec_iter.bi_size, bytes); + if (ret) goto err; if (flags & BCH_READ_last_fragment) break; - swap(bvec_iter.bi_size, bytes); bio_advance_iter(&rbio->bio, &bvec_iter, bytes); err: if (ret == -BCH_ERR_data_read_retry_csum_err_maybe_userspace) diff --git a/fs/bcachefs/io_read.h b/fs/bcachefs/io_read.h index cd21950417f6..c78025d863e0 100644 --- a/fs/bcachefs/io_read.h +++ b/fs/bcachefs/io_read.h @@ -137,8 +137,10 @@ static inline void bch2_read_extent(struct btree_trans *trans, enum btree_id data_btree, struct bkey_s_c k, unsigned offset_into_extent, unsigned flags) { - __bch2_read_extent(trans, rbio, rbio->bio.bi_iter, read_pos, - data_btree, k, offset_into_extent, NULL, flags, -1); + int ret = __bch2_read_extent(trans, rbio, rbio->bio.bi_iter, read_pos, + data_btree, k, offset_into_extent, NULL, flags, -1); + /* __bch2_read_extent only returns errors if BCH_READ_in_retry is set */ + WARN(ret, "unhandled error from __bch2_read_extent()"); } int __bch2_read(struct btree_trans *, struct bch_read_bio *, struct bvec_iter, |