diff options
| -rw-r--r-- | fs/btrfs/disk-io.c | 20 | ||||
| -rw-r--r-- | fs/btrfs/extent_io.c | 2 | ||||
| -rw-r--r-- | fs/btrfs/extent_io.h | 1 | ||||
| -rw-r--r-- | fs/btrfs/send.c | 2 | ||||
| -rw-r--r-- | fs/btrfs/transaction.c | 3 | ||||
| -rw-r--r-- | fs/btrfs/transaction.h | 2 |
6 files changed, 27 insertions, 3 deletions
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index d9698fda2d12..98fe70193397 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -329,6 +329,8 @@ static int verify_parent_transid(struct extent_io_tree *io_tree, { struct extent_state *cached_state = NULL; int ret; + bool need_lock = (current->journal_info == + (void *)BTRFS_SEND_TRANS_STUB); if (!parent_transid || btrfs_header_generation(eb) == parent_transid) return 0; @@ -336,6 +338,11 @@ static int verify_parent_transid(struct extent_io_tree *io_tree, if (atomic) return -EAGAIN; + if (need_lock) { + btrfs_tree_read_lock(eb); + btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK); + } + lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1, 0, &cached_state); if (extent_buffer_uptodate(eb) && @@ -347,10 +354,21 @@ static int verify_parent_transid(struct extent_io_tree *io_tree, "found %llu\n", eb->start, parent_transid, btrfs_header_generation(eb)); ret = 1; - clear_extent_buffer_uptodate(eb); + + /* + * Things reading via commit roots that don't have normal protection, + * like send, can have a really old block in cache that may point at a + * block that has been free'd and re-allocated. So don't clear uptodate + * if we find an eb that is under IO (dirty/writeback) because we could + * end up reading in the stale data and then writing it back out and + * making everybody very sad. + */ + if (!extent_buffer_under_io(eb)) + clear_extent_buffer_uptodate(eb); out: unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1, &cached_state, GFP_NOFS); + btrfs_tree_read_unlock_blocking(eb); return ret; } diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index fd78c84821c8..d35a3ca15fb5 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -4315,7 +4315,7 @@ static void __free_extent_buffer(struct extent_buffer *eb) kmem_cache_free(extent_buffer_cache, eb); } -static int extent_buffer_under_io(struct extent_buffer *eb) +int extent_buffer_under_io(struct extent_buffer *eb) { return (atomic_read(&eb->io_pages) || test_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags) || diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h index 58b27e5ab521..c488b45237bf 100644 --- a/fs/btrfs/extent_io.h +++ b/fs/btrfs/extent_io.h @@ -320,6 +320,7 @@ int set_extent_buffer_dirty(struct extent_buffer *eb); int set_extent_buffer_uptodate(struct extent_buffer *eb); int clear_extent_buffer_uptodate(struct extent_buffer *eb); int extent_buffer_uptodate(struct extent_buffer *eb); +int extent_buffer_under_io(struct extent_buffer *eb); int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset, unsigned long min_len, char **map, unsigned long *map_start, diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c index 9b6da9d55f9a..d00534b78382 100644 --- a/fs/btrfs/send.c +++ b/fs/btrfs/send.c @@ -5718,7 +5718,9 @@ long btrfs_ioctl_send(struct file *mnt_file, void __user *arg_) NULL); sort_clone_roots = 1; + current->journal_info = (void *)BTRFS_SEND_TRANS_STUB; ret = send_subvol(sctx); + current->journal_info = NULL; if (ret < 0) goto out; diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index a04707f740d6..038177cfabbb 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -375,7 +375,8 @@ start_transaction(struct btrfs_root *root, u64 num_items, unsigned int type, if (test_bit(BTRFS_FS_STATE_ERROR, &root->fs_info->fs_state)) return ERR_PTR(-EROFS); - if (current->journal_info) { + if (current->journal_info && + current->journal_info != (void *)BTRFS_SEND_TRANS_STUB) { WARN_ON(type & TRANS_EXTWRITERS); h = current->journal_info; h->use_count++; diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h index 6ac037e9f9f0..2bcba89d952e 100644 --- a/fs/btrfs/transaction.h +++ b/fs/btrfs/transaction.h @@ -78,6 +78,8 @@ struct btrfs_transaction { #define TRANS_EXTWRITERS (__TRANS_USERSPACE | __TRANS_START | \ __TRANS_ATTACH) +#define BTRFS_SEND_TRANS_STUB 1 + struct btrfs_trans_handle { u64 transid; u64 bytes_reserved; |