Commit 3eeb3226 authored by Josef Bacik's avatar Josef Bacik Committed by David Sterba
Browse files

btrfs: migrate nocow and reservation helpers 



These are relatively straightforward as well.

Signed-off-by: default avatarJosef Bacik <josef@toxicpanda.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 3cad1284

fs/btrfs/block-group.c

+82 −0
Original line number Diff line number Diff line
@@ -2,6 +2,7 @@ 


#include "ctree.h"

#include "block-group.h"

#include "space-info.h"



void btrfs_get_block_group(struct btrfs_block_group_cache *cache)

{
@@ -118,3 +119,84 @@ struct btrfs_block_group_cache *btrfs_next_block_group( 
	spin_unlock(&fs_info->block_group_cache_lock);

	return cache;

}



bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr)

{

	struct btrfs_block_group_cache *bg;

	bool ret = true;



	bg = btrfs_lookup_block_group(fs_info, bytenr);

	if (!bg)

		return false;



	spin_lock(&bg->lock);

	if (bg->ro)

		ret = false;

	else

		atomic_inc(&bg->nocow_writers);

	spin_unlock(&bg->lock);



	/* No put on block group, done by btrfs_dec_nocow_writers */

	if (!ret)

		btrfs_put_block_group(bg);



	return ret;

}



void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr)

{

	struct btrfs_block_group_cache *bg;



	bg = btrfs_lookup_block_group(fs_info, bytenr);

	ASSERT(bg);

	if (atomic_dec_and_test(&bg->nocow_writers))

		wake_up_var(&bg->nocow_writers);

	/*

	 * Once for our lookup and once for the lookup done by a previous call

	 * to btrfs_inc_nocow_writers()

	 */

	btrfs_put_block_group(bg);

	btrfs_put_block_group(bg);

}



void btrfs_wait_nocow_writers(struct btrfs_block_group_cache *bg)

{

	wait_var_event(&bg->nocow_writers, !atomic_read(&bg->nocow_writers));

}



void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,

					const u64 start)

{

	struct btrfs_block_group_cache *bg;



	bg = btrfs_lookup_block_group(fs_info, start);

	ASSERT(bg);

	if (atomic_dec_and_test(&bg->reservations))

		wake_up_var(&bg->reservations);

	btrfs_put_block_group(bg);

}



void btrfs_wait_block_group_reservations(struct btrfs_block_group_cache *bg)

{

	struct btrfs_space_info *space_info = bg->space_info;



	ASSERT(bg->ro);



	if (!(bg->flags & BTRFS_BLOCK_GROUP_DATA))

		return;



	/*

	 * Our block group is read only but before we set it to read only,

	 * some task might have had allocated an extent from it already, but it

	 * has not yet created a respective ordered extent (and added it to a

	 * root's list of ordered extents).

	 * Therefore wait for any task currently allocating extents, since the

	 * block group's reservations counter is incremented while a read lock

	 * on the groups' semaphore is held and decremented after releasing

	 * the read access on that semaphore and creating the ordered extent.

	 */

	down_write(&space_info->groups_sem);

	up_write(&space_info->groups_sem);



	wait_var_event(&bg->reservations, !atomic_read(&bg->reservations));

}

fs/btrfs/block-group.h

+6 −0
Original line number Diff line number Diff line
@@ -159,5 +159,11 @@ struct btrfs_block_group_cache *btrfs_next_block_group( 
		struct btrfs_block_group_cache *cache);

void btrfs_get_block_group(struct btrfs_block_group_cache *cache);

void btrfs_put_block_group(struct btrfs_block_group_cache *cache);

void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,

					const u64 start);

void btrfs_wait_block_group_reservations(struct btrfs_block_group_cache *bg);

bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr);

void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr);

void btrfs_wait_nocow_writers(struct btrfs_block_group_cache *bg);



#endif /* BTRFS_BLOCK_GROUP_H */

fs/btrfs/ctree.h

+0 −6
Original line number Diff line number Diff line
@@ -2473,12 +2473,6 @@ static inline u64 btrfs_calc_trunc_metadata_size(struct btrfs_fs_info *fs_info, 
	return (u64)fs_info->nodesize * BTRFS_MAX_LEVEL * num_items;

}



void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,

					 const u64 start);

void btrfs_wait_block_group_reservations(struct btrfs_block_group_cache *bg);

bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr);

void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr);

void btrfs_wait_nocow_writers(struct btrfs_block_group_cache *bg);

int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,

			   unsigned long count);

void btrfs_cleanup_ref_head_accounting(struct btrfs_fs_info *fs_info,

fs/btrfs/extent-tree.c

+0 −82
Original line number Diff line number Diff line
@@ -3561,51 +3561,6 @@ int btrfs_extent_readonly(struct btrfs_fs_info *fs_info, u64 bytenr) 
	return readonly;

}



bool btrfs_inc_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr)

{

	struct btrfs_block_group_cache *bg;

	bool ret = true;



	bg = btrfs_lookup_block_group(fs_info, bytenr);

	if (!bg)

		return false;



	spin_lock(&bg->lock);

	if (bg->ro)

		ret = false;

	else

		atomic_inc(&bg->nocow_writers);

	spin_unlock(&bg->lock);



	/* no put on block group, done by btrfs_dec_nocow_writers */

	if (!ret)

		btrfs_put_block_group(bg);



	return ret;



}



void btrfs_dec_nocow_writers(struct btrfs_fs_info *fs_info, u64 bytenr)

{

	struct btrfs_block_group_cache *bg;



	bg = btrfs_lookup_block_group(fs_info, bytenr);

	ASSERT(bg);

	if (atomic_dec_and_test(&bg->nocow_writers))

		wake_up_var(&bg->nocow_writers);

	/*

	 * Once for our lookup and once for the lookup done by a previous call

	 * to btrfs_inc_nocow_writers()

	 */

	btrfs_put_block_group(bg);

	btrfs_put_block_group(bg);

}



void btrfs_wait_nocow_writers(struct btrfs_block_group_cache *bg)

{

	wait_var_event(&bg->nocow_writers, !atomic_read(&bg->nocow_writers));

}



static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)

{

	u64 extra_flags = chunk_to_extended(flags) &
@@ -4277,43 +4232,6 @@ btrfs_inc_block_group_reservations(struct btrfs_block_group_cache *bg) 
	atomic_inc(&bg->reservations);

}



void btrfs_dec_block_group_reservations(struct btrfs_fs_info *fs_info,

					const u64 start)

{

	struct btrfs_block_group_cache *bg;



	bg = btrfs_lookup_block_group(fs_info, start);

	ASSERT(bg);

	if (atomic_dec_and_test(&bg->reservations))

		wake_up_var(&bg->reservations);

	btrfs_put_block_group(bg);

}



void btrfs_wait_block_group_reservations(struct btrfs_block_group_cache *bg)

{

	struct btrfs_space_info *space_info = bg->space_info;



	ASSERT(bg->ro);



	if (!(bg->flags & BTRFS_BLOCK_GROUP_DATA))

		return;



	/*

	 * Our block group is read only but before we set it to read only,

	 * some task might have had allocated an extent from it already, but it

	 * has not yet created a respective ordered extent (and added it to a

	 * root's list of ordered extents).

	 * Therefore wait for any task currently allocating extents, since the

	 * block group's reservations counter is incremented while a read lock

	 * on the groups' semaphore is held and decremented after releasing

	 * the read access on that semaphore and creating the ordered extent.

	 */

	down_write(&space_info->groups_sem);

	up_write(&space_info->groups_sem);



	wait_var_event(&bg->reservations, !atomic_read(&bg->reservations));

}



/**

 * btrfs_add_reserved_bytes - update the block_group and space info counters

 * @cache:	The cache we are manipulating