Commit 138082f3 authored by Naohiro Aota's avatar Naohiro Aota Committed by David Sterba
Browse files

btrfs: extend btrfs_rmap_block for specifying a device 



btrfs_rmap_block currently reverse-maps the physical addresses on all
devices to the corresponding logical addresses.

Extend the function to match to a specified device. The old functionality
of querying all devices is left intact by specifying NULL as target
device.

A block_device instead of a btrfs_device is passed into btrfs_rmap_block,
as this function is intended to reverse-map the result of a bio, which
only has a block_device.

Also export the function for later use.

Reviewed-by: default avatarJosef Bacik <josef@toxicpanda.com>
Signed-off-by: default avatarNaohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent cacb2cea

fs/btrfs/block-group.c

+11 −5
Original line number Diff line number Diff line
@@ -1588,6 +1588,7 @@ static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags) 
 *

 * @fs_info:       the filesystem

 * @chunk_start:   logical address of block group

 * @bdev:	   physical device to resolve, can be NULL to indicate any device

 * @physical:	   physical address to map to logical addresses

 * @logical:	   return array of logical addresses which map to @physical

 * @naddrs:	   length of @logical
@@ -1597,9 +1598,9 @@ static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags) 
 * Used primarily to exclude those portions of a block group that contain super

 * block copies.

 */

EXPORT_FOR_TESTS

int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,

		     u64 physical, u64 **logical, int *naddrs, int *stripe_len)

		     struct block_device *bdev, u64 physical, u64 **logical,

		     int *naddrs, int *stripe_len)

{

	struct extent_map *em;

	struct map_lookup *map;
@@ -1617,6 +1618,7 @@ int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start, 
	map = em->map_lookup;

	data_stripe_length = em->orig_block_len;

	io_stripe_size = map->stripe_len;

	chunk_start = em->start;



	/* For RAID5/6 adjust to a full IO stripe length */

	if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
@@ -1631,14 +1633,18 @@ int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start, 
	for (i = 0; i < map->num_stripes; i++) {

		bool already_inserted = false;

		u64 stripe_nr;

		u64 offset;

		int j;



		if (!in_range(physical, map->stripes[i].physical,

			      data_stripe_length))

			continue;



		if (bdev && map->stripes[i].dev->bdev != bdev)

			continue;



		stripe_nr = physical - map->stripes[i].physical;

		stripe_nr = div64_u64(stripe_nr, map->stripe_len);

		stripe_nr = div64_u64_rem(stripe_nr, map->stripe_len, &offset);



		if (map->type & BTRFS_BLOCK_GROUP_RAID10) {

			stripe_nr = stripe_nr * map->num_stripes + i;
@@ -1652,7 +1658,7 @@ int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start, 
		 * instead of map->stripe_len

		 */



		bytenr = chunk_start + stripe_nr * io_stripe_size;

		bytenr = chunk_start + stripe_nr * io_stripe_size + offset;



		/* Ensure we don't add duplicate addresses */

		for (j = 0; j < nr; j++) {
@@ -1694,7 +1700,7 @@ static int exclude_super_stripes(struct btrfs_block_group *cache) 


	for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {

		bytenr = btrfs_sb_offset(i);

		ret = btrfs_rmap_block(fs_info, cache->start,

		ret = btrfs_rmap_block(fs_info, cache->start, NULL,

				       bytenr, &logical, &nr, &stripe_len);

		if (ret)

			return ret;

fs/btrfs/block-group.h

+3 −5
Original line number Diff line number Diff line
@@ -277,6 +277,9 @@ void btrfs_put_block_group_cache(struct btrfs_fs_info *info); 
int btrfs_free_block_groups(struct btrfs_fs_info *info);

void btrfs_wait_space_cache_v1_finished(struct btrfs_block_group *cache,

				struct btrfs_caching_control *caching_ctl);

int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,

		       struct block_device *bdev, u64 physical, u64 **logical,

		       int *naddrs, int *stripe_len);



static inline u64 btrfs_data_alloc_profile(struct btrfs_fs_info *fs_info)

{
@@ -303,9 +306,4 @@ static inline int btrfs_block_group_done(struct btrfs_block_group *cache) 
void btrfs_freeze_block_group(struct btrfs_block_group *cache);

void btrfs_unfreeze_block_group(struct btrfs_block_group *cache);



#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS

int btrfs_rmap_block(struct btrfs_fs_info *fs_info, u64 chunk_start,

		     u64 physical, u64 **logical, int *naddrs, int *stripe_len);

#endif



#endif /* BTRFS_BLOCK_GROUP_H */

fs/btrfs/tests/extent-map-tests.c

+1 −1
Original line number Diff line number Diff line
@@ -507,7 +507,7 @@ static int test_rmap_block(struct btrfs_fs_info *fs_info, 
		goto out_free;

	}



	ret = btrfs_rmap_block(fs_info, em->start, btrfs_sb_offset(1),

	ret = btrfs_rmap_block(fs_info, em->start, NULL, btrfs_sb_offset(1),

			       &logical, &out_ndaddrs, &out_stripe_len);

	if (ret || (out_ndaddrs == 0 && test->expected_mapped_addr)) {

		test_err("didn't rmap anything but expected %d",