Commit cff82672 authored by David Sterba's avatar David Sterba
Browse files

btrfs: read number of data stripes from map only once 



There are several places that call nr_data_stripes, but this value does
not change.

Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 72ad8131

fs/btrfs/scrub.c

+4 −4
Original line number Diff line number Diff line
@@ -2660,18 +2660,18 @@ static int get_raid56_logic_offset(u64 physical, int num, 
	u64 last_offset;

	u32 stripe_index;

	u32 rot;

	const int data_stripes = nr_data_stripes(map);



	last_offset = (physical - map->stripes[num].physical) *

		      nr_data_stripes(map);

	last_offset = (physical - map->stripes[num].physical) * data_stripes;

	if (stripe_start)

		*stripe_start = last_offset;



	*offset = last_offset;

	for (i = 0; i < nr_data_stripes(map); i++) {

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

		*offset = last_offset + i * map->stripe_len;



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

		stripe_nr = div_u64(stripe_nr, nr_data_stripes(map));

		stripe_nr = div_u64(stripe_nr, data_stripes);



		/* Work out the disk rotation on this stripe-set */

		stripe_nr = div_u64_rem(stripe_nr, map->num_stripes, &rot);

fs/btrfs/volumes.c

+9 −8
Original line number Diff line number Diff line
@@ -5918,6 +5918,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, 
	u64 stripe_nr;

	u64 stripe_len;

	u32 stripe_index;

	int data_stripes;

	int i;

	int ret = 0;

	int num_stripes;
@@ -5949,6 +5950,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, 
	 * to get to this block

	 */

	stripe_nr = div64_u64(stripe_nr, stripe_len);

	data_stripes = nr_data_stripes(map);



	stripe_offset = stripe_nr * stripe_len;

	if (offset < stripe_offset) {
@@ -5965,7 +5967,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, 


	/* if we're here for raid56, we need to know the stripe aligned start */

	if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {

		unsigned long full_stripe_len = stripe_len * nr_data_stripes(map);

		unsigned long full_stripe_len = stripe_len * data_stripes;

		raid56_full_stripe_start = offset;



		/* allow a write of a full stripe, but make sure we don't
@@ -5983,7 +5985,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, 
		   stripe (on a single disk). */

		if ((map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) &&

		    (op == BTRFS_MAP_WRITE)) {

			max_len = stripe_len * nr_data_stripes(map) -

			max_len = stripe_len * data_stripes -

				(offset - raid56_full_stripe_start);

		} else {

			/* we limit the length of each bio to what fits in a stripe */
@@ -6073,7 +6075,7 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, 
		if (need_raid_map && (need_full_stripe(op) || mirror_num > 1)) {

			/* push stripe_nr back to the start of the full stripe */

			stripe_nr = div64_u64(raid56_full_stripe_start,

					stripe_len * nr_data_stripes(map));

					stripe_len * data_stripes);



			/* RAID[56] write or recovery. Return all stripes */

			num_stripes = map->num_stripes;
@@ -6089,10 +6091,9 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, 
			 * Mirror #3 is RAID6 Q block.

			 */

			stripe_nr = div_u64_rem(stripe_nr,

					nr_data_stripes(map), &stripe_index);

					data_stripes, &stripe_index);

			if (mirror_num > 1)

				stripe_index = nr_data_stripes(map) +

						mirror_num - 2;

				stripe_index = data_stripes + mirror_num - 2;



			/* We distribute the parity blocks across stripes */

			div_u64_rem(stripe_nr + stripe_index, map->num_stripes,
@@ -6150,8 +6151,8 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, 
		div_u64_rem(stripe_nr, num_stripes, &rot);



		/* Fill in the logical address of each stripe */

		tmp = stripe_nr * nr_data_stripes(map);

		for (i = 0; i < nr_data_stripes(map); i++)

		tmp = stripe_nr * data_stripes;

		for (i = 0; i < data_stripes; i++)

			bbio->raid_map[(i+rot) % num_stripes] =

				em->start + (tmp + i) * map->stripe_len;