Merge tag 'for-6.11-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

torvalds · torvalds · commit e4fc196f5ba3 · 2024-07-30T19:28:36.000-07:00
Pull btrfs fixes from David Sterba:

 - fix regression in extent map rework when handling insertion of
   overlapping compressed extent

 - fix unexpected file length when appending to a file using direct io
   and buffer not faulted in

 - in zoned mode, fix accounting of unusable space when flipping
   read-only block group back to read-write

 - fix page locking when COWing an inline range, assertion failure found
   by syzbot

 - fix calculation of space info in debugging print

 - tree-checker, add validation of data reference item

 - fix a few -Wmaybe-uninitialized build warnings

* tag 'for-6.11-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: initialize location to fix -Wmaybe-uninitialized in btrfs_lookup_dentry()
  btrfs: fix corruption after buffer fault in during direct IO append write
  btrfs: zoned: fix zone_unusable accounting on making block group read-write again
  btrfs: do not subtract delalloc from avail bytes
  btrfs: make cow_file_range_inline() honor locked_page on error
  btrfs: fix corrupt read due to bad offset of a compressed extent map
  btrfs: tree-checker: validate dref root and objectid
diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
@@ -1223,8 +1223,8 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 	block_group->space_info->total_bytes -= block_group->length;
 	block_group->space_info->bytes_readonly -=
 		(block_group->length - block_group->zone_unusable);
-	block_group->space_info->bytes_zone_unusable -=
-		block_group->zone_unusable;
+	btrfs_space_info_update_bytes_zone_unusable(fs_info, block_group->space_info,
+						    -block_group->zone_unusable);
 	block_group->space_info->disk_total -= block_group->length * factor;
 
 	spin_unlock(&block_group->space_info->lock);
@@ -1396,7 +1396,8 @@ static int inc_block_group_ro(struct btrfs_block_group *cache, int force)
 		if (btrfs_is_zoned(cache->fs_info)) {
 			/* Migrate zone_unusable bytes to readonly */
 			sinfo->bytes_readonly += cache->zone_unusable;
-			sinfo->bytes_zone_unusable -= cache->zone_unusable;
+			btrfs_space_info_update_bytes_zone_unusable(cache->fs_info, sinfo,
+								    -cache->zone_unusable);
 			cache->zone_unusable = 0;
 		}
 		cache->ro++;
@@ -3056,9 +3057,11 @@ void btrfs_dec_block_group_ro(struct btrfs_block_group *cache)
 		if (btrfs_is_zoned(cache->fs_info)) {
 			/* Migrate zone_unusable bytes back */
 			cache->zone_unusable =
-				(cache->alloc_offset - cache->used) +
+				(cache->alloc_offset - cache->used - cache->pinned -
+				 cache->reserved) +
 				(cache->length - cache->zone_capacity);
-			sinfo->bytes_zone_unusable += cache->zone_unusable;
+			btrfs_space_info_update_bytes_zone_unusable(cache->fs_info, sinfo,
+								    cache->zone_unusable);
 			sinfo->bytes_readonly -= cache->zone_unusable;
 		}
 		num_bytes = cache->length - cache->reserved -
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
@@ -459,6 +459,7 @@ struct btrfs_file_private {
 	void *filldir_buf;
 	u64 last_index;
 	struct extent_state *llseek_cached_state;
+	bool fsync_skip_inode_lock;
 };
 
 static inline u32 BTRFS_LEAF_DATA_SIZE(const struct btrfs_fs_info *info)
diff --git a/fs/btrfs/direct-io.c b/fs/btrfs/direct-io.c
@@ -856,21 +856,37 @@ ssize_t btrfs_direct_write(struct kiocb *iocb, struct iov_iter *from)
 	 * So here we disable page faults in the iov_iter and then retry if we
 	 * got -EFAULT, faulting in the pages before the retry.
 	 */
+again:
 	from->nofault = true;
 	dio = btrfs_dio_write(iocb, from, written);
 	from->nofault = false;
 
-	/*
-	 * iomap_dio_complete() will call btrfs_sync_file() if we have a dsync
-	 * iocb, and that needs to lock the inode. So unlock it before calling
-	 * iomap_dio_complete() to avoid a deadlock.
-	 */
-	btrfs_inode_unlock(BTRFS_I(inode), ilock_flags);
-
-	if (IS_ERR_OR_NULL(dio))
+	if (IS_ERR_OR_NULL(dio)) {
 		ret = PTR_ERR_OR_ZERO(dio);
-	else
+	} else {
+		struct btrfs_file_private stack_private = { 0 };
+		struct btrfs_file_private *private;
+		const bool have_private = (file->private_data != NULL);
+
+		if (!have_private)
+			file->private_data = &stack_private;
+
+		/*
+		 * If we have a synchronous write, we must make sure the fsync
+		 * triggered by the iomap_dio_complete() call below doesn't
+		 * deadlock on the inode lock - we are already holding it and we
+		 * can't call it after unlocking because we may need to complete
+		 * partial writes due to the input buffer (or parts of it) not
+		 * being already faulted in.
+		 */
+		private = file->private_data;
+		private->fsync_skip_inode_lock = true;
 		ret = iomap_dio_complete(dio);
+		private->fsync_skip_inode_lock = false;
+
+		if (!have_private)
+			file->private_data = NULL;
+	}
 
 	/* No increment (+=) because iomap returns a cumulative value. */
 	if (ret > 0)
@@ -897,10 +913,12 @@ ssize_t btrfs_direct_write(struct kiocb *iocb, struct iov_iter *from)
 		} else {
 			fault_in_iov_iter_readable(from, left);
 			prev_left = left;
-			goto relock;
+			goto again;
 		}
 	}
 
+	btrfs_inode_unlock(BTRFS_I(inode), ilock_flags);
+
 	/*
 	 * If 'ret' is -ENOTBLK or we have not written all data, then it means
 	 * we must fallback to buffered IO.
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
@@ -2793,7 +2793,8 @@ static int unpin_extent_range(struct btrfs_fs_info *fs_info,
 			readonly = true;
 		} else if (btrfs_is_zoned(fs_info)) {
 			/* Need reset before reusing in a zoned block group */
-			space_info->bytes_zone_unusable += len;
+			btrfs_space_info_update_bytes_zone_unusable(fs_info, space_info,
+								    len);
 			readonly = true;
 		}
 		spin_unlock(&cache->lock);
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
@@ -664,7 +664,7 @@ static noinline int merge_extent_mapping(struct btrfs_inode *inode,
 	start_diff = start - em->start;
 	em->start = start;
 	em->len = end - start;
-	if (em->disk_bytenr < EXTENT_MAP_LAST_BYTE && !extent_map_is_compressed(em))
+	if (em->disk_bytenr < EXTENT_MAP_LAST_BYTE)
 		em->offset += start_diff;
 	return add_extent_mapping(inode, em, 0);
 }
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
@@ -1603,6 +1603,7 @@ static inline bool skip_inode_logging(const struct btrfs_log_ctx *ctx)
  */
 int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 {
+	struct btrfs_file_private *private = file->private_data;
 	struct dentry *dentry = file_dentry(file);
 	struct btrfs_inode *inode = BTRFS_I(d_inode(dentry));
 	struct btrfs_root *root = inode->root;
@@ -1612,6 +1613,7 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 	int ret = 0, err;
 	u64 len;
 	bool full_sync;
+	const bool skip_ilock = (private ? private->fsync_skip_inode_lock : false);
 
 	trace_btrfs_sync_file(file, datasync);
 
@@ -1639,7 +1641,10 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 	if (ret)
 		goto out;
 
-	btrfs_inode_lock(inode, BTRFS_ILOCK_MMAP);
+	if (skip_ilock)
+		down_write(&inode->i_mmap_lock);
+	else
+		btrfs_inode_lock(inode, BTRFS_ILOCK_MMAP);
 
 	atomic_inc(&root->log_batch);
 
@@ -1663,7 +1668,10 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 	 */
 	ret = start_ordered_ops(inode, start, end);
 	if (ret) {
-		btrfs_inode_unlock(inode, BTRFS_ILOCK_MMAP);
+		if (skip_ilock)
+			up_write(&inode->i_mmap_lock);
+		else
+			btrfs_inode_unlock(inode, BTRFS_ILOCK_MMAP);
 		goto out;
 	}
 
@@ -1788,7 +1796,10 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 	 * file again, but that will end up using the synchronization
 	 * inside btrfs_sync_log to keep things safe.
 	 */
-	btrfs_inode_unlock(inode, BTRFS_ILOCK_MMAP);
+	if (skip_ilock)
+		up_write(&inode->i_mmap_lock);
+	else
+		btrfs_inode_unlock(inode, BTRFS_ILOCK_MMAP);
 
 	if (ret == BTRFS_NO_LOG_SYNC) {
 		ret = btrfs_end_transaction(trans);
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
@@ -2723,8 +2723,10 @@ static int __btrfs_add_free_space_zoned(struct btrfs_block_group *block_group,
 	 * If the block group is read-only, we should account freed space into
 	 * bytes_readonly.
 	 */
-	if (!block_group->ro)
+	if (!block_group->ro) {
 		block_group->zone_unusable += to_unusable;
+		WARN_ON(block_group->zone_unusable > block_group->length);
+	}
 	spin_unlock(&ctl->tree_lock);
 	if (!used) {
 		spin_lock(&block_group->lock);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
@@ -714,8 +714,9 @@ static noinline int __cow_file_range_inline(struct btrfs_inode *inode, u64 offse
 	return ret;
 }
 
-static noinline int cow_file_range_inline(struct btrfs_inode *inode, u64 offset,
-					  u64 end,
+static noinline int cow_file_range_inline(struct btrfs_inode *inode,
+					  struct page *locked_page,
+					  u64 offset, u64 end,
 					  size_t compressed_size,
 					  int compress_type,
 					  struct folio *compressed_folio,
@@ -739,7 +740,10 @@ static noinline int cow_file_range_inline(struct btrfs_inode *inode, u64 offset,
 		return ret;
 	}
 
-	extent_clear_unlock_delalloc(inode, offset, end, NULL, &cached,
+	if (ret == 0)
+		locked_page = NULL;
+
+	extent_clear_unlock_delalloc(inode, offset, end, locked_page, &cached,
 				     clear_flags,
 				     PAGE_UNLOCK | PAGE_START_WRITEBACK |
 				     PAGE_END_WRITEBACK);
@@ -1043,10 +1047,10 @@ static void compress_file_range(struct btrfs_work *work)
 	 * extent for the subpage case.
 	 */
 	if (total_in < actual_end)
-		ret = cow_file_range_inline(inode, start, end, 0,
+		ret = cow_file_range_inline(inode, NULL, start, end, 0,
 					    BTRFS_COMPRESS_NONE, NULL, false);
 	else
-		ret = cow_file_range_inline(inode, start, end, total_compressed,
+		ret = cow_file_range_inline(inode, NULL, start, end, total_compressed,
 					    compress_type, folios[0], false);
 	if (ret <= 0) {
 		if (ret < 0)
@@ -1359,7 +1363,7 @@ static noinline int cow_file_range(struct btrfs_inode *inode,
 
 	if (!no_inline) {
 		/* lets try to make an inline extent */
-		ret = cow_file_range_inline(inode, start, end, 0,
+		ret = cow_file_range_inline(inode, locked_page, start, end, 0,
 					    BTRFS_COMPRESS_NONE, NULL, false);
 		if (ret <= 0) {
 			/*
@@ -5660,7 +5664,7 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
 	struct inode *inode;
 	struct btrfs_root *root = BTRFS_I(dir)->root;
 	struct btrfs_root *sub_root = root;
-	struct btrfs_key location;
+	struct btrfs_key location = { 0 };
 	u8 di_type = 0;
 	int ret = 0;
 
diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
@@ -316,7 +316,7 @@ void btrfs_add_bg_to_space_info(struct btrfs_fs_info *info,
 	found->bytes_used += block_group->used;
 	found->disk_used += block_group->used * factor;
 	found->bytes_readonly += block_group->bytes_super;
-	found->bytes_zone_unusable += block_group->zone_unusable;
+	btrfs_space_info_update_bytes_zone_unusable(info, found, block_group->zone_unusable);
 	if (block_group->length > 0)
 		found->full = 0;
 	btrfs_try_granting_tickets(info, found);
@@ -583,8 +583,7 @@ void btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
 
 		spin_lock(&cache->lock);
 		avail = cache->length - cache->used - cache->pinned -
-			cache->reserved - cache->delalloc_bytes -
-			cache->bytes_super - cache->zone_unusable;
+			cache->reserved - cache->bytes_super - cache->zone_unusable;
 		btrfs_info(fs_info,
 "block group %llu has %llu bytes, %llu used %llu pinned %llu reserved %llu delalloc %llu super %llu zone_unusable (%llu bytes available) %s",
 			   cache->start, cache->length, cache->used, cache->pinned,
diff --git a/fs/btrfs/space-info.h b/fs/btrfs/space-info.h
@@ -249,6 +249,7 @@ btrfs_space_info_update_##name(struct btrfs_fs_info *fs_info,		\
 
 DECLARE_SPACE_INFO_UPDATE(bytes_may_use, "space_info");
 DECLARE_SPACE_INFO_UPDATE(bytes_pinned, "pinned");
+DECLARE_SPACE_INFO_UPDATE(bytes_zone_unusable, "zone_unusable");
 
 int btrfs_init_space_info(struct btrfs_fs_info *fs_info);
 void btrfs_add_bg_to_space_info(struct btrfs_fs_info *info,
diff --git a/fs/btrfs/tests/extent-map-tests.c b/fs/btrfs/tests/extent-map-tests.c
@@ -900,6 +900,102 @@ static int test_case_7(struct btrfs_fs_info *fs_info, struct btrfs_inode *inode)
 	return ret;
 }
 
+/*
+ * Test a regression for compressed extent map adjustment when we attempt to
+ * add an extent map that is partially overlapped by another existing extent
+ * map. The resulting extent map offset was left unchanged despite having
+ * incremented its start offset.
+ */
+static int test_case_8(struct btrfs_fs_info *fs_info, struct btrfs_inode *inode)
+{
+	struct extent_map_tree *em_tree = &inode->extent_tree;
+	struct extent_map *em;
+	int ret;
+	int ret2;
+
+	em = alloc_extent_map();
+	if (!em) {
+		test_std_err(TEST_ALLOC_EXTENT_MAP);
+		return -ENOMEM;
+	}
+
+	/* Compressed extent for the file range [120K, 128K). */
+	em->start = SZ_1K * 120;
+	em->len = SZ_8K;
+	em->disk_num_bytes = SZ_4K;
+	em->ram_bytes = SZ_8K;
+	em->flags |= EXTENT_FLAG_COMPRESS_ZLIB;
+	write_lock(&em_tree->lock);
+	ret = btrfs_add_extent_mapping(inode, &em, em->start, em->len);
+	write_unlock(&em_tree->lock);
+	free_extent_map(em);
+	if (ret < 0) {
+		test_err("couldn't add extent map for range [120K, 128K)");
+		goto out;
+	}
+
+	em = alloc_extent_map();
+	if (!em) {
+		test_std_err(TEST_ALLOC_EXTENT_MAP);
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	/*
+	 * Compressed extent for the file range [108K, 144K), which overlaps
+	 * with the [120K, 128K) we previously inserted.
+	 */
+	em->start = SZ_1K * 108;
+	em->len = SZ_1K * 36;
+	em->disk_num_bytes = SZ_4K;
+	em->ram_bytes = SZ_1K * 36;
+	em->flags |= EXTENT_FLAG_COMPRESS_ZLIB;
+
+	/*
+	 * Try to add the extent map but with a search range of [140K, 144K),
+	 * this should succeed and adjust the extent map to the range
+	 * [128K, 144K), with a length of 16K and an offset of 20K.
+	 *
+	 * This simulates a scenario where in the subvolume tree of an inode we
+	 * have a compressed file extent item for the range [108K, 144K) and we
+	 * have an overlapping compressed extent map for the range [120K, 128K),
+	 * which was created by an encoded write, but its ordered extent was not
+	 * yet completed, so the subvolume tree doesn't have yet the file extent
+	 * item for that range - we only have the extent map in the inode's
+	 * extent map tree.
+	 */
+	write_lock(&em_tree->lock);
+	ret = btrfs_add_extent_mapping(inode, &em, SZ_1K * 140, SZ_4K);
+	write_unlock(&em_tree->lock);
+	free_extent_map(em);
+	if (ret < 0) {
+		test_err("couldn't add extent map for range [108K, 144K)");
+		goto out;
+	}
+
+	if (em->start != SZ_128K) {
+		test_err("unexpected extent map start %llu (should be 128K)", em->start);
+		ret = -EINVAL;
+		goto out;
+	}
+	if (em->len != SZ_16K) {
+		test_err("unexpected extent map length %llu (should be 16K)", em->len);
+		ret = -EINVAL;
+		goto out;
+	}
+	if (em->offset != SZ_1K * 20) {
+		test_err("unexpected extent map offset %llu (should be 20K)", em->offset);
+		ret = -EINVAL;
+		goto out;
+	}
+out:
+	ret2 = free_extent_map_tree(inode);
+	if (ret == 0)
+		ret = ret2;
+
+	return ret;
+}
+
 struct rmap_test_vector {
 	u64 raid_type;
 	u64 physical_start;
@@ -1076,6 +1172,9 @@ int btrfs_test_extent_map(void)
 	if (ret)
 		goto out;
 	ret = test_case_7(fs_info, BTRFS_I(inode));
+	if (ret)
+		goto out;
+	ret = test_case_8(fs_info, BTRFS_I(inode));
 	if (ret)
 		goto out;
 
diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c
diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h

Original file line number	Diff line number	Diff line change
`@@ -664,7 +664,7 @@ static noinline int merge_extent_mapping(struct btrfs_inode *inode,`
`664`	`664`	`start_diff = start - em->start;`
`665`	`665`	`em->start = start;`
`666`	`666`	`em->len = end - start;`
`667`		`- if (em->disk_bytenr < EXTENT_MAP_LAST_BYTE && !extent_map_is_compressed(em))`
	`667`	`+ if (em->disk_bytenr < EXTENT_MAP_LAST_BYTE)`
`668`	`668`	`em->offset += start_diff;`
`669`	`669`	`return add_extent_mapping(inode, em, 0);`
`670`	`670`	`}`