BTRFS uses bio->bi_vcnt to figure out page numbers, this
way becomes not correct once we start to enable multipage
bvec.

So use bio_for_each_segment_all() to do that instead.

Cc: Chris Mason <c...@fb.com>
Cc: Josef Bacik <jba...@fb.com>
Cc: David Sterba <dste...@suse.com>
Cc: linux-bt...@vger.kernel.org
Acked-by: David Sterba <dste...@suse.com>
Signed-off-by: Ming Lei <ming....@redhat.com>
---
 fs/btrfs/extent_io.c | 20 ++++++++++++++++----
 fs/btrfs/extent_io.h |  2 +-
 2 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 0aff9b278c19..0e7367817b92 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2258,7 +2258,7 @@ int btrfs_get_io_failure_record(struct inode *inode, u64 
start, u64 end,
        return 0;
 }
 
-bool btrfs_check_repairable(struct inode *inode, struct bio *failed_bio,
+bool btrfs_check_repairable(struct inode *inode, unsigned failed_bio_pages,
                           struct io_failure_record *failrec, int failed_mirror)
 {
        struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
@@ -2282,7 +2282,7 @@ bool btrfs_check_repairable(struct inode *inode, struct 
bio *failed_bio,
         *      a) deliver good data to the caller
         *      b) correct the bad sectors on disk
         */
-       if (failed_bio->bi_vcnt > 1) {
+       if (failed_bio_pages > 1) {
                /*
                 * to fulfill b), we need to know the exact failing sectors, as
                 * we don't want to rewrite any more than the failed ones. thus,
@@ -2355,6 +2355,17 @@ struct bio *btrfs_create_repair_bio(struct inode *inode, 
struct bio *failed_bio,
        return bio;
 }
 
+static unsigned int get_bio_pages(struct bio *bio)
+{
+       unsigned i;
+       struct bio_vec *bv;
+
+       bio_for_each_segment_all(bv, bio, i)
+               ;
+
+       return i;
+}
+
 /*
  * this is a generic handler for readpage errors (default
  * readpage_io_failed_hook). if other copies exist, read those and write back
@@ -2375,6 +2386,7 @@ static int bio_readpage_error(struct bio *failed_bio, u64 
phy_offset,
        int read_mode = 0;
        blk_status_t status;
        int ret;
+       unsigned failed_bio_pages = get_bio_pages(failed_bio);
 
        BUG_ON(bio_op(failed_bio) == REQ_OP_WRITE);
 
@@ -2382,13 +2394,13 @@ static int bio_readpage_error(struct bio *failed_bio, 
u64 phy_offset,
        if (ret)
                return ret;
 
-       if (!btrfs_check_repairable(inode, failed_bio, failrec,
+       if (!btrfs_check_repairable(inode, failed_bio_pages, failrec,
                                    failed_mirror)) {
                free_io_failure(failure_tree, tree, failrec);
                return -EIO;
        }
 
-       if (failed_bio->bi_vcnt > 1)
+       if (failed_bio_pages > 1)
                read_mode |= REQ_FAILFAST_DEV;
 
        phy_offset >>= inode->i_sb->s_blocksize_bits;
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 4f030912f3ef..300ee10f39f2 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -539,7 +539,7 @@ void btrfs_free_io_failure_record(struct btrfs_inode 
*inode, u64 start,
                u64 end);
 int btrfs_get_io_failure_record(struct inode *inode, u64 start, u64 end,
                                struct io_failure_record **failrec_ret);
-bool btrfs_check_repairable(struct inode *inode, struct bio *failed_bio,
+bool btrfs_check_repairable(struct inode *inode, unsigned failed_bio_pages,
                            struct io_failure_record *failrec, int fail_mirror);
 struct bio *btrfs_create_repair_bio(struct inode *inode, struct bio 
*failed_bio,
                                    struct io_failure_record *failrec,
-- 
2.9.4

Reply via email to