From: Qu Wenruo wqu@suse.com
[ Upstream commit 975a6a8855f45729a0fbfe2a8f2df2d3faef2a97 ]
All the error handling bugs I hit so far are all -ENOSPC from either:
- cow_file_range() - run_delalloc_nocow() - submit_uncompressed_range()
Previously when those functions failed, there was no error message at all, making the debugging much harder.
So here we introduce extra error messages for:
- cow_file_range() - run_delalloc_nocow() - submit_uncompressed_range() - writepage_delalloc() when btrfs_run_delalloc_range() failed - extent_writepage() when extent_writepage_io() failed
One example of the new debug error messages is the following one:
run fstests generic/750 at 2024-12-08 12:41:41 BTRFS: device fsid 461b25f5-e240-4543-8deb-e7c2bd01a6d3 devid 1 transid 8 /dev/mapper/test-scratch1 (253:4) scanned by mount (2436600) BTRFS info (device dm-4): first mount of filesystem 461b25f5-e240-4543-8deb-e7c2bd01a6d3 BTRFS info (device dm-4): using crc32c (crc32c-arm64) checksum algorithm BTRFS info (device dm-4): forcing free space tree for sector size 4096 with page size 65536 BTRFS info (device dm-4): using free-space-tree BTRFS warning (device dm-4): read-write for sector size 4096 with page size 65536 is experimental BTRFS info (device dm-4): checking UUID tree BTRFS error (device dm-4): cow_file_range failed, root=363 inode=412 start=503808 len=98304: -28 BTRFS error (device dm-4): run_delalloc_nocow failed, root=363 inode=412 start=503808 len=98304: -28 BTRFS error (device dm-4): failed to run delalloc range, root=363 ino=412 folio=458752 submit_bitmap=11-15 start=503808 len=98304: -28
Which shows an error from cow_file_range() which is called inside a nocow write attempt, along with the extra bitmap from writepage_delalloc().
Reviewed-by: Boris Burkov boris@bur.io Signed-off-by: Qu Wenruo wqu@suse.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Stable-dep-of: e9e3b22ddfa7 ("btrfs: fix beyond-EOF write handling") Signed-off-by: Sasha Levin sashal@kernel.org --- fs/btrfs/extent_io.c | 15 +++++++++++++++ fs/btrfs/inode.c | 12 ++++++++++++ 2 files changed, 27 insertions(+)
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index d8d9f4c95c7ab..4c5288251f78f 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -1322,6 +1322,15 @@ static noinline_for_stack int writepage_delalloc(struct btrfs_inode *inode, wbc); if (ret >= 0) last_finished_delalloc_end = found_start + found_len; + if (unlikely(ret < 0)) + btrfs_err_rl(fs_info, +"failed to run delalloc range, root=%lld ino=%llu folio=%llu submit_bitmap=%*pbl start=%llu len=%u: %d", + btrfs_root_id(inode->root), + btrfs_ino(inode), + folio_pos(folio), + fs_info->sectors_per_page, + &bio_ctrl->submit_bitmap, + found_start, found_len, ret); } else { /* * We've hit an error during previous delalloc range, @@ -1621,6 +1630,12 @@ static int extent_writepage(struct folio *folio, struct btrfs_bio_ctrl *bio_ctrl PAGE_SIZE, bio_ctrl, i_size); if (ret == 1) return 0; + if (ret < 0) + btrfs_err_rl(fs_info, +"failed to submit blocks, root=%lld inode=%llu folio=%llu submit_bitmap=%*pbl: %d", + btrfs_root_id(inode->root), btrfs_ino(inode), + folio_pos(folio), fs_info->sectors_per_page, + &bio_ctrl->submit_bitmap, ret);
bio_ctrl->wbc->nr_to_write--;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 38323620b819e..b1d450459f736 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -1163,6 +1163,10 @@ static void submit_uncompressed_range(struct btrfs_inode *inode, if (locked_folio) btrfs_folio_end_lock(inode->root->fs_info, locked_folio, start, async_extent->ram_size); + btrfs_err_rl(inode->root->fs_info, + "%s failed, root=%llu inode=%llu start=%llu len=%llu: %d", + __func__, btrfs_root_id(inode->root), + btrfs_ino(inode), start, async_extent->ram_size, ret); } }
@@ -1623,6 +1627,10 @@ static noinline int cow_file_range(struct btrfs_inode *inode, &cached, clear_bits, page_ops); btrfs_qgroup_free_data(inode, NULL, start, end - start + 1, NULL); } + btrfs_err_rl(fs_info, + "%s failed, root=%llu inode=%llu start=%llu len=%llu: %d", + __func__, btrfs_root_id(inode->root), + btrfs_ino(inode), orig_start, end + 1 - orig_start, ret); return ret; }
@@ -2373,6 +2381,10 @@ static noinline int run_delalloc_nocow(struct btrfs_inode *inode, btrfs_qgroup_free_data(inode, NULL, cur_offset, end - cur_offset + 1, NULL); } btrfs_free_path(path); + btrfs_err_rl(fs_info, + "%s failed, root=%llu inode=%llu start=%llu len=%llu: %d", + __func__, btrfs_root_id(inode->root), + btrfs_ino(inode), start, end + 1 - start, ret); return ret; }