From 975a6a8855f45729a0fbfe2a8f2df2d3faef2a97 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Thu, 12 Dec 2024 16:44:02 +1030 Subject: [PATCH] btrfs: add extra error messages for delalloc range related errors 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 Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba --- 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 5014134b9aa2..d9f856358704 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -1255,6 +1255,15 @@ 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, @@ -1553,6 +1562,12 @@ 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 7aa178e728cf..57bd601cc736 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -1132,6 +1132,10 @@ 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); } } @@ -1576,6 +1580,10 @@ out_unlock: btrfs_qgroup_free_data(inode, NULL, start + cur_alloc_size, end - start - cur_alloc_size + 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; } @@ -2322,6 +2330,10 @@ error: 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; } -- 2.50.1