Commit 4824f1f4 authored by Wang Xiaoguang's avatar Wang Xiaoguang Committed by Chris Mason
Browse files

btrfs: divide btrfs_update_reserved_bytes() into two functions 



This patch divides btrfs_update_reserved_bytes() into
btrfs_add_reserved_bytes() and btrfs_free_reserved_bytes(), and
next patch will extend btrfs_add_reserved_bytes（）to fix some
false ENOSPC error, please see later patch for detailed info.

Signed-off-by: default avatarWang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: default avatarJosef Bacik <jbacik@fb.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarChris Mason <clm@fb.com>
parent dcb40c19

fs/btrfs/extent-tree.c

+57 −40
Original line number Diff line number Diff line
@@ -104,9 +104,10 @@ static int find_next_key(struct btrfs_path *path, int level, 
			 struct btrfs_key *key);

static void dump_space_info(struct btrfs_space_info *info, u64 bytes,

			    int dump_block_groups);

static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,

				       u64 num_bytes, int reserve,

				       int delalloc);

static int btrfs_add_reserved_bytes(struct btrfs_block_group_cache *cache,

				    u64 num_bytes, int reserve, int delalloc);

static int btrfs_free_reserved_bytes(struct btrfs_block_group_cache *cache,

				     u64 num_bytes, int delalloc);

static int block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv,

			       u64 num_bytes);

int btrfs_pin_extent(struct btrfs_root *root,
@@ -6497,19 +6498,14 @@ void btrfs_wait_block_group_reservations(struct btrfs_block_group_cache *bg) 
}



/**

 * btrfs_update_reserved_bytes - update the block_group and space info counters

 * btrfs_add_reserved_bytes - update the block_group and space info counters

 * @cache:	The cache we are manipulating

 * @num_bytes:	The number of bytes in question

 * @reserve:	One of the reservation enums

 * @delalloc:   The blocks are allocated for the delalloc write

 *

 * This is called by the allocator when it reserves space, or by somebody who is

 * freeing space that was never actually used on disk.  For example if you

 * reserve some space for a new leaf in transaction A and before transaction A

 * commits you free that leaf, you call this with reserve set to 0 in order to

 * clear the reservation.

 *

 * Metadata reservations should be called with RESERVE_ALLOC so we do the proper

 * This is called by the allocator when it reserves space. Metadata

 * reservations should be called with RESERVE_ALLOC so we do the proper

 * ENOSPC accounting.  For data we handle the reservation through clearing the

 * delalloc bits in the io_tree.  We have to do this since we could end up

 * allocating less disk space for the amount of data we have reserved in the
@@ -6519,7 +6515,7 @@ void btrfs_wait_block_group_reservations(struct btrfs_block_group_cache *bg) 
 * make the reservation and return -EAGAIN, otherwise this function always

 * succeeds.

 */

static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,

static int btrfs_add_reserved_bytes(struct btrfs_block_group_cache *cache,

				    u64 num_bytes, int reserve, int delalloc)

{

	struct btrfs_space_info *space_info = cache->space_info;
@@ -6527,7 +6523,6 @@ static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache, 


	spin_lock(&space_info->lock);

	spin_lock(&cache->lock);

	if (reserve != RESERVE_FREE) {

	if (cache->ro) {

		ret = -EAGAIN;

	} else {
@@ -6543,7 +6538,31 @@ static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache, 
		if (delalloc)

			cache->delalloc_bytes += num_bytes;

	}

	} else {

	spin_unlock(&cache->lock);

	spin_unlock(&space_info->lock);

	return ret;

}



/**

 * btrfs_free_reserved_bytes - update the block_group and space info counters

 * @cache:      The cache we are manipulating

 * @num_bytes:  The number of bytes in question

 * @delalloc:   The blocks are allocated for the delalloc write

 *

 * This is called by somebody who is freeing space that was never actually used

 * on disk.  For example if you reserve some space for a new leaf in transaction

 * A and before transaction A commits you free that leaf, you call this with

 * reserve set to 0 in order to clear the reservation.

 */



static int btrfs_free_reserved_bytes(struct btrfs_block_group_cache *cache,

				     u64 num_bytes, int delalloc)

{

	struct btrfs_space_info *space_info = cache->space_info;

	int ret = 0;



	spin_lock(&space_info->lock);

	spin_lock(&cache->lock);

	if (cache->ro)

		space_info->bytes_readonly += num_bytes;

	cache->reserved -= num_bytes;
@@ -6551,12 +6570,10 @@ static int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache, 


	if (delalloc)

		cache->delalloc_bytes -= num_bytes;

	}

	spin_unlock(&cache->lock);

	spin_unlock(&space_info->lock);

	return ret;

}



void btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,

				struct btrfs_root *root)

{
@@ -7191,7 +7208,7 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans, 
		WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));



		btrfs_add_free_space(cache, buf->start, buf->len);

		btrfs_update_reserved_bytes(cache, buf->len, RESERVE_FREE, 0);

		btrfs_free_reserved_bytes(cache, buf->len, 0);

		btrfs_put_block_group(cache);

		trace_btrfs_reserved_extent_free(root, buf->start, buf->len);

		pin = 0;
@@ -7763,7 +7780,7 @@ static noinline int find_free_extent(struct btrfs_root *orig_root, 
					     search_start - offset);

		BUG_ON(offset > search_start);



		ret = btrfs_update_reserved_bytes(block_group, num_bytes,

		ret = btrfs_add_reserved_bytes(block_group, num_bytes,

				alloc_type, delalloc);

		if (ret == -EAGAIN) {

			btrfs_add_free_space(block_group, offset, num_bytes);
@@ -7995,7 +8012,7 @@ static int __btrfs_free_reserved_extent(struct btrfs_root *root, 
		if (btrfs_test_opt(root->fs_info, DISCARD))

			ret = btrfs_discard_extent(root, start, len, NULL);

		btrfs_add_free_space(cache, start, len);

		btrfs_update_reserved_bytes(cache, len, RESERVE_FREE, delalloc);

		btrfs_free_reserved_bytes(cache, len, delalloc);

		trace_btrfs_reserved_extent_free(root, start, len);

	}
@@ -8223,7 +8240,7 @@ int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans, 
	if (!block_group)

		return -EINVAL;



	ret = btrfs_update_reserved_bytes(block_group, ins->offset,

	ret = btrfs_add_reserved_bytes(block_group, ins->offset,

			RESERVE_ALLOC_NO_ACCOUNT, 0);

	BUG_ON(ret); /* logic error */

	ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,