diff options
-rw-r--r-- | fs/btrfs/backref.c | 6 | ||||
-rw-r--r-- | fs/btrfs/backref.h | 3 | ||||
-rw-r--r-- | fs/btrfs/delayed-ref.c | 4 | ||||
-rw-r--r-- | fs/btrfs/qgroup.c | 38 | ||||
-rw-r--r-- | fs/btrfs/qgroup.h | 2 | ||||
-rw-r--r-- | fs/btrfs/tests/qgroup-tests.c | 20 |
6 files changed, 48 insertions, 25 deletions
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index 7a8a2fc19533..78b202d198b8 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -1488,15 +1488,15 @@ static int btrfs_find_all_roots_safe(struct btrfs_trans_handle *trans, int btrfs_find_all_roots(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, u64 bytenr, u64 time_seq, struct ulist **roots, - bool ignore_offset) + bool ignore_offset, bool skip_commit_root_sem) { int ret; - if (!trans) + if (!trans && !skip_commit_root_sem) down_read(&fs_info->commit_root_sem); ret = btrfs_find_all_roots_safe(trans, fs_info, bytenr, time_seq, roots, ignore_offset); - if (!trans) + if (!trans && !skip_commit_root_sem) up_read(&fs_info->commit_root_sem); return ret; } diff --git a/fs/btrfs/backref.h b/fs/btrfs/backref.h index 17abde7f794c..ff5f07f9940b 100644 --- a/fs/btrfs/backref.h +++ b/fs/btrfs/backref.h @@ -47,7 +47,8 @@ int btrfs_find_all_leafs(struct btrfs_trans_handle *trans, const u64 *extent_item_pos, bool ignore_offset); int btrfs_find_all_roots(struct btrfs_trans_handle *trans, struct btrfs_fs_info *fs_info, u64 bytenr, - u64 time_seq, struct ulist **roots, bool ignore_offset); + u64 time_seq, struct ulist **roots, bool ignore_offset, + bool skip_commit_root_sem); char *btrfs_ref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path, u32 name_len, unsigned long name_off, struct extent_buffer *eb_in, u64 parent, diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c index 06bc842ecdb3..ca848b183474 100644 --- a/fs/btrfs/delayed-ref.c +++ b/fs/btrfs/delayed-ref.c @@ -974,7 +974,7 @@ int btrfs_add_delayed_tree_ref(struct btrfs_trans_handle *trans, kmem_cache_free(btrfs_delayed_tree_ref_cachep, ref); if (qrecord_inserted) - btrfs_qgroup_trace_extent_post(fs_info, record); + btrfs_qgroup_trace_extent_post(trans, record); return 0; } @@ -1069,7 +1069,7 @@ int btrfs_add_delayed_data_ref(struct btrfs_trans_handle *trans, if (qrecord_inserted) - return btrfs_qgroup_trace_extent_post(fs_info, record); + return btrfs_qgroup_trace_extent_post(trans, record); return 0; } diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c index 07ec06d4e972..0fa121171ca1 100644 --- a/fs/btrfs/qgroup.c +++ b/fs/btrfs/qgroup.c @@ -1704,17 +1704,39 @@ int btrfs_qgroup_trace_extent_nolock(struct btrfs_fs_info *fs_info, return 0; } -int btrfs_qgroup_trace_extent_post(struct btrfs_fs_info *fs_info, +int btrfs_qgroup_trace_extent_post(struct btrfs_trans_handle *trans, struct btrfs_qgroup_extent_record *qrecord) { struct ulist *old_root; u64 bytenr = qrecord->bytenr; int ret; - ret = btrfs_find_all_roots(NULL, fs_info, bytenr, 0, &old_root, false); + /* + * We are always called in a context where we are already holding a + * transaction handle. Often we are called when adding a data delayed + * reference from btrfs_truncate_inode_items() (truncating or unlinking), + * in which case we will be holding a write lock on extent buffer from a + * subvolume tree. In this case we can't allow btrfs_find_all_roots() to + * acquire fs_info->commit_root_sem, because that is a higher level lock + * that must be acquired before locking any extent buffers. + * + * So we want btrfs_find_all_roots() to not acquire the commit_root_sem + * but we can't pass it a non-NULL transaction handle, because otherwise + * it would not use commit roots and would lock extent buffers, causing + * a deadlock if it ends up trying to read lock the same extent buffer + * that was previously write locked at btrfs_truncate_inode_items(). + * + * So pass a NULL transaction handle to btrfs_find_all_roots() and + * explicitly tell it to not acquire the commit_root_sem - if we are + * holding a transaction handle we don't need its protection. + */ + ASSERT(trans != NULL); + + ret = btrfs_find_all_roots(NULL, trans->fs_info, bytenr, 0, &old_root, + false, true); if (ret < 0) { - fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT; - btrfs_warn(fs_info, + trans->fs_info->qgroup_flags |= BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT; + btrfs_warn(trans->fs_info, "error accounting new delayed refs extent (err code: %d), quota inconsistent", ret); return 0; @@ -1758,7 +1780,7 @@ int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans, u64 bytenr, kfree(record); return 0; } - return btrfs_qgroup_trace_extent_post(fs_info, record); + return btrfs_qgroup_trace_extent_post(trans, record); } int btrfs_qgroup_trace_leaf_items(struct btrfs_trans_handle *trans, @@ -2629,7 +2651,7 @@ int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans) /* Search commit root to find old_roots */ ret = btrfs_find_all_roots(NULL, fs_info, record->bytenr, 0, - &record->old_roots, false); + &record->old_roots, false, false); if (ret < 0) goto cleanup; } @@ -2645,7 +2667,7 @@ int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans) * current root. It's safe inside commit_transaction(). */ ret = btrfs_find_all_roots(trans, fs_info, - record->bytenr, BTRFS_SEQ_LAST, &new_roots, false); + record->bytenr, BTRFS_SEQ_LAST, &new_roots, false, false); if (ret < 0) goto cleanup; if (qgroup_to_skip) { @@ -3179,7 +3201,7 @@ static int qgroup_rescan_leaf(struct btrfs_trans_handle *trans, num_bytes = found.offset; ret = btrfs_find_all_roots(NULL, fs_info, found.objectid, 0, - &roots, false); + &roots, false, false); if (ret < 0) goto out; /* For rescan, just pass old_roots as NULL */ diff --git a/fs/btrfs/qgroup.h b/fs/btrfs/qgroup.h index 7283e4f549af..880e9df0dac1 100644 --- a/fs/btrfs/qgroup.h +++ b/fs/btrfs/qgroup.h @@ -298,7 +298,7 @@ int btrfs_qgroup_trace_extent_nolock( * using current root, then we can move all expensive backref walk out of * transaction committing, but not now as qgroup accounting will be wrong again. */ -int btrfs_qgroup_trace_extent_post(struct btrfs_fs_info *fs_info, +int btrfs_qgroup_trace_extent_post(struct btrfs_trans_handle *trans, struct btrfs_qgroup_extent_record *qrecord); /* diff --git a/fs/btrfs/tests/qgroup-tests.c b/fs/btrfs/tests/qgroup-tests.c index f3137285a9e2..98b5aaba46f1 100644 --- a/fs/btrfs/tests/qgroup-tests.c +++ b/fs/btrfs/tests/qgroup-tests.c @@ -224,7 +224,7 @@ static int test_no_shared_qgroup(struct btrfs_root *root, * quota. */ ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &old_roots, - false); + false, false); if (ret) { ulist_free(old_roots); test_err("couldn't find old roots: %d", ret); @@ -237,7 +237,7 @@ static int test_no_shared_qgroup(struct btrfs_root *root, return ret; ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &new_roots, - false); + false, false); if (ret) { ulist_free(old_roots); ulist_free(new_roots); @@ -261,7 +261,7 @@ static int test_no_shared_qgroup(struct btrfs_root *root, new_roots = NULL; ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &old_roots, - false); + false, false); if (ret) { ulist_free(old_roots); test_err("couldn't find old roots: %d", ret); @@ -273,7 +273,7 @@ static int test_no_shared_qgroup(struct btrfs_root *root, return -EINVAL; ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &new_roots, - false); + false, false); if (ret) { ulist_free(old_roots); ulist_free(new_roots); @@ -325,7 +325,7 @@ static int test_multiple_refs(struct btrfs_root *root, } ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &old_roots, - false); + false, false); if (ret) { ulist_free(old_roots); test_err("couldn't find old roots: %d", ret); @@ -338,7 +338,7 @@ static int test_multiple_refs(struct btrfs_root *root, return ret; ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &new_roots, - false); + false, false); if (ret) { ulist_free(old_roots); ulist_free(new_roots); @@ -360,7 +360,7 @@ static int test_multiple_refs(struct btrfs_root *root, } ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &old_roots, - false); + false, false); if (ret) { ulist_free(old_roots); test_err("couldn't find old roots: %d", ret); @@ -373,7 +373,7 @@ static int test_multiple_refs(struct btrfs_root *root, return ret; ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &new_roots, - false); + false, false); if (ret) { ulist_free(old_roots); ulist_free(new_roots); @@ -401,7 +401,7 @@ static int test_multiple_refs(struct btrfs_root *root, } ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &old_roots, - false); + false, false); if (ret) { ulist_free(old_roots); test_err("couldn't find old roots: %d", ret); @@ -414,7 +414,7 @@ static int test_multiple_refs(struct btrfs_root *root, return ret; ret = btrfs_find_all_roots(&trans, fs_info, nodesize, 0, &new_roots, - false); + false, false); if (ret) { ulist_free(old_roots); ulist_free(new_roots); |