1 files changed, 51 insertions, 13 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 6862cd7e21a9..7ba1218b1630 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -650,12 +650,18 @@ cont:
 						     page_error_op |
 						     PAGE_END_WRITEBACK);
 
-			for (i = 0; i < nr_pages; i++) {
-				WARN_ON(pages[i]->mapping);
-				put_page(pages[i]);
+			/*
+			 * Ensure we only free the compressed pages if we have
+			 * them allocated, as we can still reach here with
+			 * inode_need_compress() == false.
+			 */
+			if (pages) {
+				for (i = 0; i < nr_pages; i++) {
+					WARN_ON(pages[i]->mapping);
+					put_page(pages[i]);
+				}
+				kfree(pages);
 			}
-			kfree(pages);
-
 			return 0;
 		}
 	}
@@ -4041,6 +4047,8 @@ int btrfs_delete_subvolume(struct inode *dir, struct dentry *dentry)
 		}
 	}
 
+	free_anon_bdev(dest->anon_dev);
+	dest->anon_dev = 0;
 out_end_trans:
 	trans->block_rsv = NULL;
 	trans->bytes_reserved = 0;
@@ -4511,11 +4519,13 @@ int btrfs_truncate_block(struct inode *inode, loff_t from, loff_t len,
 	struct extent_state *cached_state = NULL;
 	struct extent_changeset *data_reserved = NULL;
 	char *kaddr;
+	bool only_release_metadata = false;
 	u32 blocksize = fs_info->sectorsize;
 	pgoff_t index = from >> PAGE_SHIFT;
 	unsigned offset = from & (blocksize - 1);
 	struct page *page;
 	gfp_t mask = btrfs_alloc_write_mask(mapping);
+	size_t write_bytes = blocksize;
 	int ret = 0;
 	u64 block_start;
 	u64 block_end;
@@ -4527,11 +4537,27 @@ int btrfs_truncate_block(struct inode *inode, loff_t from, loff_t len,
 	block_start = round_down(from, blocksize);
 	block_end = block_start + blocksize - 1;
 
-	ret = btrfs_delalloc_reserve_space(inode, &data_reserved,
-					   block_start, blocksize);
-	if (ret)
-		goto out;
 
+	ret = btrfs_check_data_free_space(inode, &data_reserved, block_start,
+					  blocksize);
+	if (ret < 0) {
+		if ((BTRFS_I(inode)->flags & (BTRFS_INODE_NODATACOW |
+					      BTRFS_INODE_PREALLOC)) &&
+		    btrfs_check_can_nocow(BTRFS_I(inode), block_start,
+					  &write_bytes, false) > 0) {
+			/* For nocow case, no need to reserve data space */
+			only_release_metadata = true;
+		} else {
+			goto out;
+		}
+	}
+	ret = btrfs_delalloc_reserve_metadata(BTRFS_I(inode), blocksize);
+	if (ret < 0) {
+		if (!only_release_metadata)
+			btrfs_free_reserved_data_space(inode, data_reserved,
+					block_start, blocksize);
+		goto out;
+	}
 again:
 	page = find_or_create_page(mapping, index, mask);
 	if (!page) {
@@ -4600,14 +4626,26 @@ again:
 	set_page_dirty(page);
 	unlock_extent_cached(io_tree, block_start, block_end, &cached_state);
 
+	if (only_release_metadata)
+		set_extent_bit(&BTRFS_I(inode)->io_tree, block_start,
+				block_end, EXTENT_NORESERVE, NULL, NULL,
+				GFP_NOFS);
+
 out_unlock:
-	if (ret)
-		btrfs_delalloc_release_space(inode, data_reserved, block_start,
-					     blocksize, true);
+	if (ret) {
+		if (only_release_metadata)
+			btrfs_delalloc_release_metadata(BTRFS_I(inode),
+					blocksize, true);
+		else
+			btrfs_delalloc_release_space(inode, data_reserved,
+					block_start, blocksize, true);
+	}
 	btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize);
 	unlock_page(page);
 	put_page(page);
 out:
+	if (only_release_metadata)
+		btrfs_drew_write_unlock(&BTRFS_I(inode)->root->snapshot_lock);
 	extent_changeset_free(data_reserved);
 	return ret;
 }
@@ -6595,7 +6633,7 @@ struct extent_map *btrfs_get_extent(struct btrfs_inode *inode,
 	    extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
 		/* Only regular file could have regular/prealloc extent */
 		if (!S_ISREG(inode->vfs_inode.i_mode)) {
-			ret = -EUCLEAN;
+			err = -EUCLEAN;
 			btrfs_crit(fs_info,
 		"regular/prealloc extent found for non-regular inode %llu",
 				   btrfs_ino(inode));