From 14543774bd67a64f616431e5c9d1472f58979841 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Tue, 24 Nov 2015 16:23:54 +0000 Subject: [PATCH] Btrfs: fix error path when failing to submit bio for direct IO write Commit 61de718fceb6 ("Btrfs: fix memory corruption on failure to submit bio for direct IO") fixed problems with the error handling code after we fail to submit a bio for direct IO. However there were 2 problems that it did not address when the failure is due to memory allocation failures for direct IO writes: 1) We considered that there could be only one ordered extent for the whole IO range, which is not always true, as we can have multiple; 2) It did not set the bit BTRFS_ORDERED_IO_DONE in the ordered extent, which can make other tasks running btrfs_wait_logged_extents() hang forever, since they wait for that bit to be set. The general assumption is that regardless of an error, the BTRFS_ORDERED_IO_DONE is always set and it precedes setting the bit BTRFS_ORDERED_COMPLETE. Fix these issues by moving part of the btrfs_endio_direct_write() handler into a new helper function and having that new helper function called when we fail to allocate memory to submit the bio (and its private object) for a direct IO write. Signed-off-by: Filipe Manana Reviewed-by: Liu Bo --- fs/btrfs/inode.c | 54 ++++++++++++++++++++++++------------------------ 1 file changed, 27 insertions(+), 27 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index f82d1f4460dd..66106b48b478 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -7995,22 +7995,22 @@ static void btrfs_endio_direct_read(struct bio *bio) bio_put(bio); } -static void btrfs_endio_direct_write(struct bio *bio) +static void btrfs_endio_direct_write_update_ordered(struct inode *inode, + const u64 offset, + const u64 bytes, + const int uptodate) { - struct btrfs_dio_private *dip = bio->bi_private; - struct inode *inode = dip->inode; struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_ordered_extent *ordered = NULL; - u64 ordered_offset = dip->logical_offset; - u64 ordered_bytes = dip->bytes; - struct bio *dio_bio; + u64 ordered_offset = offset; + u64 ordered_bytes = bytes; int ret; again: ret = btrfs_dec_test_first_ordered_pending(inode, &ordered, &ordered_offset, ordered_bytes, - !bio->bi_error); + uptodate); if (!ret) goto out_test; @@ -8023,13 +8023,22 @@ out_test: * our bio might span multiple ordered extents. If we haven't * completed the accounting for the whole dio, go back and try again */ - if (ordered_offset < dip->logical_offset + dip->bytes) { - ordered_bytes = dip->logical_offset + dip->bytes - - ordered_offset; + if (ordered_offset < offset + bytes) { + ordered_bytes = offset + bytes - ordered_offset; ordered = NULL; goto again; } - dio_bio = dip->dio_bio; +} + +static void btrfs_endio_direct_write(struct bio *bio) +{ + struct btrfs_dio_private *dip = bio->bi_private; + struct bio *dio_bio = dip->dio_bio; + + btrfs_endio_direct_write_update_ordered(dip->inode, + dip->logical_offset, + dip->bytes, + !bio->bi_error); kfree(dip); @@ -8365,24 +8374,15 @@ free_ordered: dip = NULL; io_bio = NULL; } else { - if (write) { - struct btrfs_ordered_extent *ordered; - - ordered = btrfs_lookup_ordered_extent(inode, - file_offset); - set_bit(BTRFS_ORDERED_IOERR, &ordered->flags); - /* - * Decrements our ref on the ordered extent and removes - * the ordered extent from the inode's ordered tree, - * doing all the proper resource cleanup such as for the - * reserved space and waking up any waiters for this - * ordered extent (through btrfs_remove_ordered_extent). - */ - btrfs_finish_ordered_io(ordered); - } else { + if (write) + btrfs_endio_direct_write_update_ordered(inode, + file_offset, + dio_bio->bi_iter.bi_size, + 0); + else unlock_extent(&BTRFS_I(inode)->io_tree, file_offset, file_offset + dio_bio->bi_iter.bi_size - 1); - } + dio_bio->bi_error = -EIO; /* * Releases and cleans up our dio_bio, no need to bio_put() -- 2.39.2