md/raid1: Allocate spare to store replacement devices and their bios.

In RAID1, a replacement is much like a normal device, so we just
double the size of the relevant arrays and look at all possible
devices for reads and writes.

Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index ab8113cff7c9f853cfc4b1a9fec9b86e6756fd48..97d5ff648eb4fbc6b7436eb8304ae037720c3b86 100644 (file)
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -135,7 +135,7 @@ out_free_pages:
                        put_page(r1_bio->bios[j]->bi_io_vec[i].bv_page);
        j = -1;
 out_free_bio:
-       while ( ++j < pi->raid_disks )
+       while (++j < pi->raid_disks)
                bio_put(r1_bio->bios[j]);
        r1bio_pool_free(r1_bio, data);
        return NULL;
@@ -164,7 +164,7 @@ static void put_all_bios(struct r1conf *conf, struct r1bio *r1_bio)
 {
        int i;
 
-       for (i = 0; i < conf->raid_disks; i++) {
+       for (i = 0; i < conf->raid_disks * 2; i++) {
                struct bio **bio = r1_bio->bios + i;
                if (!BIO_SPECIAL(*bio))
                        bio_put(*bio);
@@ -185,7 +185,7 @@ static void put_buf(struct r1bio *r1_bio)
        struct r1conf *conf = r1_bio->mddev->private;
        int i;
 
-       for (i=0; i<conf->raid_disks; i++) {
+       for (i = 0; i < conf->raid_disks * 2; i++) {
                struct bio *bio = r1_bio->bios[i];
                if (bio->bi_end_io)
                        rdev_dec_pending(conf->mirrors[i].rdev, r1_bio->mddev);
@@ -280,11 +280,11 @@ static int find_bio_disk(struct r1bio *r1_bio, struct bio *bio)
        struct r1conf *conf = r1_bio->mddev->private;
        int raid_disks = conf->raid_disks;
 
-       for (mirror = 0; mirror < raid_disks; mirror++)
+       for (mirror = 0; mirror < raid_disks * 2; mirror++)
                if (r1_bio->bios[mirror] == bio)
                        break;
 
-       BUG_ON(mirror == raid_disks);
+       BUG_ON(mirror == raid_disks * 2);
        update_head_pos(mirror, r1_bio);
 
        return mirror;
@@ -506,7 +506,7 @@ static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sect
                start_disk = conf->last_used;
        }
 
-       for (i = 0 ; i < conf->raid_disks ; i++) {
+       for (i = 0 ; i < conf->raid_disks * 2 ; i++) {
                sector_t dist;
                sector_t first_bad;
                int bad_sectors;
@@ -975,7 +975,7 @@ read_again:
         */
        plugged = mddev_check_plugged(mddev);
 
-       disks = conf->raid_disks;
+       disks = conf->raid_disks * 2;
  retry_write:
        blocked_rdev = NULL;
        rcu_read_lock();
@@ -1493,7 +1493,7 @@ static int fix_sync_read_error(struct r1bio *r1_bio)
                                }
                        }
                        d++;
-                       if (d == conf->raid_disks)
+                       if (d == conf->raid_disks * 2)
                                d = 0;
                } while (!success && d != r1_bio->read_disk);
 
@@ -1510,7 +1510,7 @@ static int fix_sync_read_error(struct r1bio *r1_bio)
                               mdname(mddev),
                               bdevname(bio->bi_bdev, b),
                               (unsigned long long)r1_bio->sector);
-                       for (d = 0; d < conf->raid_disks; d++) {
+                       for (d = 0; d < conf->raid_disks * 2; d++) {
                                rdev = conf->mirrors[d].rdev;
                                if (!rdev || test_bit(Faulty, &rdev->flags))
                                        continue;
@@ -1536,7 +1536,7 @@ static int fix_sync_read_error(struct r1bio *r1_bio)
                /* write it back and re-read */
                while (d != r1_bio->read_disk) {
                        if (d == 0)
-                               d = conf->raid_disks;
+                               d = conf->raid_disks * 2;
                        d--;
                        if (r1_bio->bios[d]->bi_end_io != end_sync_read)
                                continue;
@@ -1551,7 +1551,7 @@ static int fix_sync_read_error(struct r1bio *r1_bio)
                d = start;
                while (d != r1_bio->read_disk) {
                        if (d == 0)
-                               d = conf->raid_disks;
+                               d = conf->raid_disks * 2;
                        d--;
                        if (r1_bio->bios[d]->bi_end_io != end_sync_read)
                                continue;
@@ -1584,7 +1584,7 @@ static int process_checks(struct r1bio *r1_bio)
        int primary;
        int i;
 
-       for (primary = 0; primary < conf->raid_disks; primary++)
+       for (primary = 0; primary < conf->raid_disks * 2; primary++)
                if (r1_bio->bios[primary]->bi_end_io == end_sync_read &&
                    test_bit(BIO_UPTODATE, &r1_bio->bios[primary]->bi_flags)) {
                        r1_bio->bios[primary]->bi_end_io = NULL;
@@ -1592,7 +1592,7 @@ static int process_checks(struct r1bio *r1_bio)
                        break;
                }
        r1_bio->read_disk = primary;
-       for (i = 0; i < conf->raid_disks; i++) {
+       for (i = 0; i < conf->raid_disks * 2; i++) {
                int j;
                int vcnt = r1_bio->sectors >> (PAGE_SHIFT- 9);
                struct bio *pbio = r1_bio->bios[primary];
@@ -1656,7 +1656,7 @@ static void sync_request_write(struct mddev *mddev, struct r1bio *r1_bio)
 {
        struct r1conf *conf = mddev->private;
        int i;
-       int disks = conf->raid_disks;
+       int disks = conf->raid_disks * 2;
        struct bio *bio, *wbio;
 
        bio = r1_bio->bios[r1_bio->read_disk];
@@ -1737,7 +1737,7 @@ static void fix_read_error(struct r1conf *conf, int read_disk,
                                success = 1;
                        else {
                                d++;
-                               if (d == conf->raid_disks)
+                               if (d == conf->raid_disks * 2)
                                        d = 0;
                        }
                } while (!success && d != read_disk);
@@ -1753,7 +1753,7 @@ static void fix_read_error(struct r1conf *conf, int read_disk,
                start = d;
                while (d != read_disk) {
                        if (d==0)
-                               d = conf->raid_disks;
+                               d = conf->raid_disks * 2;
                        d--;
                        rdev = conf->mirrors[d].rdev;
                        if (rdev &&
@@ -1765,7 +1765,7 @@ static void fix_read_error(struct r1conf *conf, int read_disk,
                while (d != read_disk) {
                        char b[BDEVNAME_SIZE];
                        if (d==0)
-                               d = conf->raid_disks;
+                               d = conf->raid_disks * 2;
                        d--;
                        rdev = conf->mirrors[d].rdev;
                        if (rdev &&
@@ -1887,7 +1887,7 @@ static void handle_sync_write_finished(struct r1conf *conf, struct r1bio *r1_bio
 {
        int m;
        int s = r1_bio->sectors;
-       for (m = 0; m < conf->raid_disks ; m++) {
+       for (m = 0; m < conf->raid_disks * 2 ; m++) {
                struct md_rdev *rdev = conf->mirrors[m].rdev;
                struct bio *bio = r1_bio->bios[m];
                if (bio->bi_end_io == NULL)
@@ -1909,7 +1909,7 @@ static void handle_sync_write_finished(struct r1conf *conf, struct r1bio *r1_bio
 static void handle_write_finished(struct r1conf *conf, struct r1bio *r1_bio)
 {
        int m;
-       for (m = 0; m < conf->raid_disks ; m++)
+       for (m = 0; m < conf->raid_disks * 2 ; m++)
                if (r1_bio->bios[m] == IO_MADE_GOOD) {
                        struct md_rdev *rdev = conf->mirrors[m].rdev;
                        rdev_clear_badblocks(rdev,
@@ -2184,7 +2184,7 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr, int *skipp
        r1_bio->state = 0;
        set_bit(R1BIO_IsSync, &r1_bio->state);
 
-       for (i=0; i < conf->raid_disks; i++) {
+       for (i = 0; i < conf->raid_disks * 2; i++) {
                struct md_rdev *rdev;
                bio = r1_bio->bios[i];
 
@@ -2254,7 +2254,7 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr, int *skipp
                 * need to mark them bad on all write targets
                 */
                int ok = 1;
-               for (i = 0 ; i < conf->raid_disks ; i++)
+               for (i = 0 ; i < conf->raid_disks * 2 ; i++)
                        if (r1_bio->bios[i]->bi_end_io == end_sync_write) {
                                struct md_rdev *rdev =
                                        rcu_dereference(conf->mirrors[i].rdev);
@@ -2323,7 +2323,7 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr, int *skipp
                                len = sync_blocks<<9;
                }
 
-               for (i=0 ; i < conf->raid_disks; i++) {
+               for (i = 0 ; i < conf->raid_disks * 2; i++) {
                        bio = r1_bio->bios[i];
                        if (bio->bi_end_io) {
                                page = bio->bi_io_vec[bio->bi_vcnt].bv_page;
@@ -2356,7 +2356,7 @@ static sector_t sync_request(struct mddev *mddev, sector_t sector_nr, int *skipp
         */
        if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
                atomic_set(&r1_bio->remaining, read_targets);
-               for (i=0; i<conf->raid_disks; i++) {
+               for (i = 0; i < conf->raid_disks * 2; i++) {
                        bio = r1_bio->bios[i];
                        if (bio->bi_end_io == end_sync_read) {
                                md_sync_acct(bio->bi_bdev, nr_sectors);
@@ -2393,7 +2393,8 @@ static struct r1conf *setup_conf(struct mddev *mddev)
        if (!conf)
                goto abort;
 
-       conf->mirrors = kzalloc(sizeof(struct mirror_info)*mddev->raid_disks,
+       conf->mirrors = kzalloc(sizeof(struct mirror_info)
+                               * mddev->raid_disks * 2,
                                 GFP_KERNEL);
        if (!conf->mirrors)
                goto abort;
@@ -2405,7 +2406,7 @@ static struct r1conf *setup_conf(struct mddev *mddev)
        conf->poolinfo = kzalloc(sizeof(*conf->poolinfo), GFP_KERNEL);
        if (!conf->poolinfo)
                goto abort;
-       conf->poolinfo->raid_disks = mddev->raid_disks;
+       conf->poolinfo->raid_disks = mddev->raid_disks * 2;
        conf->r1bio_pool = mempool_create(NR_RAID1_BIOS, r1bio_pool_alloc,
                                          r1bio_pool_free,
                                          conf->poolinfo);
@@ -2438,7 +2439,7 @@ static struct r1conf *setup_conf(struct mddev *mddev)
        conf->recovery_disabled = mddev->recovery_disabled - 1;
 
        conf->last_used = -1;
-       for (i = 0; i < conf->raid_disks; i++) {
+       for (i = 0; i < conf->raid_disks * 2; i++) {
 
                disk = conf->mirrors + i;
 
@@ -2665,7 +2666,7 @@ static int raid1_reshape(struct mddev *mddev)
        if (!newpoolinfo)
                return -ENOMEM;
        newpoolinfo->mddev = mddev;
-       newpoolinfo->raid_disks = raid_disks;
+       newpoolinfo->raid_disks = raid_disks * 2;
 
        newpool = mempool_create(NR_RAID1_BIOS, r1bio_pool_alloc,
                                 r1bio_pool_free, newpoolinfo);
@@ -2673,7 +2674,8 @@ static int raid1_reshape(struct mddev *mddev)
                kfree(newpoolinfo);
                return -ENOMEM;
        }
-       newmirrors = kzalloc(sizeof(struct mirror_info) * raid_disks, GFP_KERNEL);
+       newmirrors = kzalloc(sizeof(struct mirror_info) * raid_disks * 2,
+                            GFP_KERNEL);
        if (!newmirrors) {
                kfree(newpoolinfo);
                mempool_destroy(newpool);

diff --git a/drivers/md/raid1.h b/drivers/md/raid1.h
index c732b6cce935283a6adb826a641bb023accf081e..80ded139314cf8a649729ce8e22915ca11bbd17f 100644 (file)
--- a/drivers/md/raid1.h
+++ b/drivers/md/raid1.h
@@ -12,6 +12,9 @@ struct mirror_info {
  * pool was allocated for, so they know how much to allocate and free.
  * mddev->raid_disks cannot be used, as it can change while a pool is active
  * These two datums are stored in a kmalloced struct.
+ * The 'raid_disks' here is twice the raid_disks in r1conf.
+ * This allows space for each 'real' device can have a replacement in the
+ * second half of the array.
  */
 
 struct pool_info {
@@ -21,7 +24,9 @@ struct pool_info {
 
 struct r1conf {
        struct mddev            *mddev;
-       struct mirror_info              *mirrors;
+       struct mirror_info      *mirrors;       /* twice 'raid_disks' to
+                                                * allow for replacements.
+                                                */
        int                     raid_disks;
 
        /* When choose the best device for a read (read_balance())