Commit e183eaed authored by NeilBrown's avatar NeilBrown
Browse files

md/raid5: prepare for allowing reshape to change layout 



Add prev_algo to raid5_conf_t along the same lines as prev_chunk
and previous_raid_disks.

Signed-off-by: default avatarNeilBrown <neilb@suse.de>
parent 784052ec

drivers/md/raid5.c

+19 −13
Original line number Diff line number Diff line
@@ -1273,6 +1273,8 @@ static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector, 
	int pd_idx, qd_idx;

	int ddf_layout = 0;

	sector_t new_sector;

	int algorithm = previous ? conf->prev_algo

				 : conf->algorithm;

	int sectors_per_chunk = previous ? (conf->prev_chunk >> 9)

					 : (conf->chunk_size >> 9);

	int raid_disks = previous ? conf->previous_raid_disks
@@ -1307,7 +1309,7 @@ static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector, 
		pd_idx = data_disks;

		break;

	case 5:

		switch (conf->algorithm) {

		switch (algorithm) {

		case ALGORITHM_LEFT_ASYMMETRIC:

			pd_idx = data_disks - stripe % raid_disks;

			if (*dd_idx >= pd_idx)
@@ -1335,13 +1337,13 @@ static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector, 
			break;

		default:

			printk(KERN_ERR "raid5: unsupported algorithm %d\n",

				conf->algorithm);

				algorithm);

			BUG();

		}

		break;

	case 6:



		switch (conf->algorithm) {

		switch (algorithm) {

		case ALGORITHM_LEFT_ASYMMETRIC:

			pd_idx = raid_disks - 1 - (stripe % raid_disks);

			qd_idx = pd_idx + 1;
@@ -1454,7 +1456,7 @@ static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector, 


		default:

			printk(KERN_CRIT "raid6: unsupported algorithm %d\n",

			       conf->algorithm);

			       algorithm);

			BUG();

		}

		break;
@@ -1481,6 +1483,8 @@ static sector_t compute_blocknr(struct stripe_head *sh, int i, int previous) 
	sector_t new_sector = sh->sector, check;

	int sectors_per_chunk = previous ? (conf->prev_chunk >> 9)

					 : (conf->chunk_size >> 9);

	int algorithm = previous ? conf->prev_algo

				 : conf->algorithm;

	sector_t stripe;

	int chunk_offset;

	int chunk_number, dummy1, dd_idx = i;
@@ -1497,7 +1501,7 @@ static sector_t compute_blocknr(struct stripe_head *sh, int i, int previous) 
	switch(conf->level) {

	case 4: break;

	case 5:

		switch (conf->algorithm) {

		switch (algorithm) {

		case ALGORITHM_LEFT_ASYMMETRIC:

		case ALGORITHM_RIGHT_ASYMMETRIC:

			if (i > sh->pd_idx)
@@ -1516,14 +1520,14 @@ static sector_t compute_blocknr(struct stripe_head *sh, int i, int previous) 
			break;

		default:

			printk(KERN_ERR "raid5: unsupported algorithm %d\n",

			       conf->algorithm);

			       algorithm);

			BUG();

		}

		break;

	case 6:

		if (i == sh->qd_idx)

			return 0; /* It is the Q disk */

		switch (conf->algorithm) {

		switch (algorithm) {

		case ALGORITHM_LEFT_ASYMMETRIC:

		case ALGORITHM_RIGHT_ASYMMETRIC:

		case ALGORITHM_ROTATING_ZERO_RESTART:
@@ -1571,7 +1575,7 @@ static sector_t compute_blocknr(struct stripe_head *sh, int i, int previous) 
			break;

		default:

			printk(KERN_CRIT "raid6: unsupported algorithm %d\n",

			       conf->algorithm);

			       algorithm);

			BUG();

		}

		break;
@@ -4330,8 +4334,10 @@ static raid5_conf_t *setup_conf(mddev_t *mddev) 
	conf->algorithm = mddev->new_layout;

	conf->max_nr_stripes = NR_STRIPES;

	conf->reshape_progress = mddev->reshape_position;

	if (conf->reshape_progress != MaxSector)

	if (conf->reshape_progress != MaxSector) {

		conf->prev_chunk = mddev->chunk_size;

		conf->prev_algo = mddev->layout;

	}



	memory = conf->max_nr_stripes * (sizeof(struct stripe_head) +

		 conf->raid_disks * ((sizeof(struct bio) + PAGE_SIZE))) / 1024;
@@ -4474,12 +4480,12 @@ static int run(mddev_t *mddev) 
		printk("raid5: raid level %d set %s active with %d out of %d"

		       " devices, algorithm %d\n", conf->level, mdname(mddev),

		       mddev->raid_disks-mddev->degraded, mddev->raid_disks,

			conf->algorithm);

		       mddev->new_layout);

	else

		printk(KERN_ALERT "raid5: raid level %d set %s active with %d"

			" out of %d devices, algorithm %d\n", conf->level,

			mdname(mddev), mddev->raid_disks - mddev->degraded,

			mddev->raid_disks, conf->algorithm);

			mddev->raid_disks, mddev->new_layout);



	print_raid5_conf(conf);

drivers/md/raid5.h

+1 −1
Original line number Diff line number Diff line
@@ -350,7 +350,7 @@ struct raid5_private_data { 
	 */

	sector_t		reshape_safe;

	int			previous_raid_disks;

	int			prev_chunk;

	int			prev_chunk, prev_algo;

	short			generation; /* increments with every reshape */



	struct list_head	handle_list; /* stripes needing handling */