Commit cf6d1aa4 authored by Boris Burkov's avatar Boris Burkov Committed by David Sterba
Browse files

btrfs: add function to create and return an ordered extent 



Currently, btrfs_add_ordered_extent allocates a new ordered extent, adds
it to the rb_tree, but doesn't return a referenced pointer to the
caller. There are cases where it is useful for the creator of a new
ordered_extent to hang on to such a pointer, so add a new function
btrfs_alloc_ordered_extent which is the same as
btrfs_add_ordered_extent, except it takes an additional reference count
and returns a pointer to the ordered_extent. Implement
btrfs_add_ordered_extent as btrfs_alloc_ordered_extent followed by
dropping the new reference and handling the IS_ERR case.

The type of flags in btrfs_alloc_ordered_extent and
btrfs_add_ordered_extent is changed from unsigned int to unsigned long
so it's unified with the other ordered extent functions.

Reviewed-by: default avatarFilipe Manana <fdmanana@suse.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarNaohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: default avatarJosef Bacik <josef@toxicpanda.com>
Tested-by: default avatarJohannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: default avatarBoris Burkov <boris@bur.io>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent cf32e41f

fs/btrfs/ordered-data.c

+37 −9
Original line number Diff line number Diff line
@@ -160,13 +160,15 @@ static inline struct rb_node *tree_search(struct btrfs_ordered_inode_tree *tree, 
 * @compress_type:   Compression algorithm used for data.

 *

 * Most of these parameters correspond to &struct btrfs_file_extent_item. The

 * tree is given a single reference on the ordered extent that was inserted.

 * tree is given a single reference on the ordered extent that was inserted, and

 * the returned pointer is given a second reference.

 *

 * Return: 0 or -ENOMEM.

 * Return: the new ordered extent or error pointer.

 */

int btrfs_add_ordered_extent(struct btrfs_inode *inode, u64 file_offset,

struct btrfs_ordered_extent *btrfs_alloc_ordered_extent(

			struct btrfs_inode *inode, u64 file_offset,

			u64 num_bytes, u64 ram_bytes, u64 disk_bytenr,

			     u64 disk_num_bytes, u64 offset, unsigned flags,

			u64 disk_num_bytes, u64 offset, unsigned long flags,

			int compress_type)

{

	struct btrfs_root *root = inode->root;
@@ -181,7 +183,7 @@ int btrfs_add_ordered_extent(struct btrfs_inode *inode, u64 file_offset, 
		/* For nocow write, we can release the qgroup rsv right now */

		ret = btrfs_qgroup_free_data(inode, NULL, file_offset, num_bytes);

		if (ret < 0)

			return ret;

			return ERR_PTR(ret);

		ret = 0;

	} else {

		/*
@@ -190,11 +192,11 @@ int btrfs_add_ordered_extent(struct btrfs_inode *inode, u64 file_offset, 
		 */

		ret = btrfs_qgroup_release_data(inode, file_offset, num_bytes);

		if (ret < 0)

			return ret;

			return ERR_PTR(ret);

	}

	entry = kmem_cache_zalloc(btrfs_ordered_extent_cache, GFP_NOFS);

	if (!entry)

		return -ENOMEM;

		return ERR_PTR(-ENOMEM);



	entry->file_offset = file_offset;

	entry->num_bytes = num_bytes;
@@ -256,6 +258,32 @@ int btrfs_add_ordered_extent(struct btrfs_inode *inode, u64 file_offset, 
	btrfs_mod_outstanding_extents(inode, 1);

	spin_unlock(&inode->lock);



	/* One ref for the returned entry to match semantics of lookup. */

	refcount_inc(&entry->refs);



	return entry;

}



/*

 * Add a new btrfs_ordered_extent for the range, but drop the reference instead

 * of returning it to the caller.

 */

int btrfs_add_ordered_extent(struct btrfs_inode *inode, u64 file_offset,

			     u64 num_bytes, u64 ram_bytes, u64 disk_bytenr,

			     u64 disk_num_bytes, u64 offset, unsigned flags,

			     int compress_type)

{

	struct btrfs_ordered_extent *ordered;



	ordered = btrfs_alloc_ordered_extent(inode, file_offset, num_bytes,

					     ram_bytes, disk_bytenr,

					     disk_num_bytes, offset, flags,

					     compress_type);



	if (IS_ERR(ordered))

		return PTR_ERR(ordered);

	btrfs_put_ordered_extent(ordered);



	return 0;

}

fs/btrfs/ordered-data.h

+5 −0
Original line number Diff line number Diff line
@@ -178,6 +178,11 @@ void btrfs_mark_ordered_io_finished(struct btrfs_inode *inode, 
bool btrfs_dec_test_ordered_pending(struct btrfs_inode *inode,

				    struct btrfs_ordered_extent **cached,

				    u64 file_offset, u64 io_size);

struct btrfs_ordered_extent *btrfs_alloc_ordered_extent(

			struct btrfs_inode *inode, u64 file_offset,

			u64 num_bytes, u64 ram_bytes, u64 disk_bytenr,

			u64 disk_num_bytes, u64 offset, unsigned long flags,

			int compress_type);

int btrfs_add_ordered_extent(struct btrfs_inode *inode, u64 file_offset,

			     u64 num_bytes, u64 ram_bytes, u64 disk_bytenr,

			     u64 disk_num_bytes, u64 offset, unsigned flags,