### Comments for ChangeSet
Remove concept of 'spare' drive for multipath.
Multipath now treats all working devices as
active and does io to to first working one.
----------- Diffstat output ------------
./drivers/md/multipath.c | 287 ++-------------------------------------
./include/linux/raid/multipath.h | 1
2 files changed, 20 insertions(+), 268 deletions(-)
--- ./drivers/md/multipath.c 2002/07/18 12:02:01 1.9
+++ ./drivers/md/multipath.c 2002/07/18 12:02:21 1.10
@@ -55,8 +55,6 @@ static mdk_personality_t multipath_perso
static spinlock_t retry_list_lock = SPIN_LOCK_UNLOCKED;
struct multipath_bh *multipath_retry_list = NULL, **multipath_retry_tail;
-static int multipath_spare_write(mddev_t *, int);
-static int multipath_spare_active(mddev_t *mddev, mdp_disk_t **d);
static void *mp_pool_alloc(int gfp_flags, void *data)
{
@@ -155,7 +153,7 @@ static int multipath_read_balance (multi
{
int disk;
- for (disk = 0; disk < conf->raid_disks; disk++)
+ for (disk = 0; disk < MD_SB_DISKS; disk++)
if (conf->multipaths[disk].operational)
return disk;
BUG();
@@ -239,20 +237,10 @@ static int multipath_error (mddev_t *mdd
multipath_conf_t *conf = mddev_to_conf(mddev);
struct multipath_info * multipaths = conf->multipaths;
int disks = MD_SB_DISKS;
- int other_paths = 1;
int i;
- if (conf->working_disks == 1) {
- other_paths = 0;
- for (i = 0; i < disks; i++) {
- if (multipaths[i].spare) {
- other_paths = 1;
- break;
- }
- }
- }
- if (!other_paths) {
+ if (conf->working_disks <= 1) {
/*
* Uh oh, we can do nothing if this is our last path, but
* first check if this is a queued request for a device
@@ -263,6 +251,7 @@ static int multipath_error (mddev_t *mdd
return 0;
}
printk (LAST_DISK);
+ return 1; /* leave it active... it's all we have */
} else {
/*
* Mark disk as unusable
@@ -273,24 +262,6 @@ static int multipath_error (mddev_t *mdd
break;
}
}
- if (!conf->working_disks) {
- int err = 1;
- mdp_disk_t *spare;
- mdp_super_t *sb = mddev->sb;
-
- spare = get_spare(mddev);
- if (spare) {
- err = multipath_spare_write(mddev, spare->number);
- printk("got DISKOP_SPARE_WRITE err: %d. (spare_faulty(): %d)\n", err, disk_faulty(spare));
- }
- if (!err && !disk_faulty(spare)) {
- multipath_spare_active(mddev, &spare);
- mark_disk_sync(spare);
- mark_disk_active(spare);
- sb->active_disks++;
- sb->spare_disks--;
- }
- }
}
return 0;
}
@@ -315,183 +286,15 @@ static void print_multipath_conf (multip
for (i = 0; i < MD_SB_DISKS; i++) {
tmp = conf->multipaths + i;
- if (tmp->spare || tmp->operational || tmp->number ||
+ if (tmp->operational || tmp->number ||
tmp->raid_disk || tmp->used_slot)
- printk(" disk%d, s:%d, o:%d, n:%d rd:%d us:%d dev:%s\n",
- i, tmp->spare,tmp->operational,
+ printk(" disk%d, o:%d, n:%d rd:%d us:%d dev:%s\n",
+ i,tmp->operational,
tmp->number,tmp->raid_disk,tmp->used_slot,
bdev_partition_name(tmp->bdev));
}
}
-/*
- * Find the spare disk ... (can only be in the 'high' area of the array)
- */
-static struct multipath_info *find_spare(mddev_t *mddev, int number)
-{
- multipath_conf_t *conf = mddev->private;
- int i;
- for (i = conf->raid_disks; i < MD_SB_DISKS; i++) {
- struct multipath_info *p = conf->multipaths + i;
- if (p->spare && p->number == number)
- return p;
- }
- return NULL;
-}
-
-static int multipath_spare_inactive(mddev_t *mddev)
-{
- multipath_conf_t *conf = mddev->private;
- struct multipath_info *p;
- int err = 0;
-
- print_multipath_conf(conf);
- spin_lock_irq(&conf->device_lock);
- p = find_spare(mddev, mddev->spare->number);
- if (p) {
- p->operational = 0;
- } else {
- MD_BUG();
- err = 1;
- }
- spin_unlock_irq(&conf->device_lock);
-
- print_multipath_conf(conf);
- return err;
-}
-
-static int multipath_spare_write(mddev_t *mddev, int number)
-{
- multipath_conf_t *conf = mddev->private;
- struct multipath_info *p;
- int err = 0;
-
- print_multipath_conf(conf);
- spin_lock_irq(&conf->device_lock);
- p = find_spare(mddev, number);
- if (p) {
- p->operational = 1;
- } else {
- MD_BUG();
- err = 1;
- }
- spin_unlock_irq(&conf->device_lock);
-
- print_multipath_conf(conf);
- return err;
-}
-
-static int multipath_spare_active(mddev_t *mddev, mdp_disk_t **d)
-{
- int err = 0;
- int i, failed_disk=-1, spare_disk=-1;
- multipath_conf_t *conf = mddev->private;
- struct multipath_info *tmp, *sdisk, *fdisk;
- mdp_super_t *sb = mddev->sb;
- mdp_disk_t *failed_desc, *spare_desc;
- mdk_rdev_t *spare_rdev, *failed_rdev;
-
- print_multipath_conf(conf);
- spin_lock_irq(&conf->device_lock);
- /*
- * Find the failed disk within the MULTIPATH configuration ...
- * (this can only be in the first conf->working_disks part)
- */
- for (i = 0; i < conf->raid_disks; i++) {
- tmp = conf->multipaths + i;
- if ((!tmp->operational && !tmp->spare) ||
- !tmp->used_slot) {
- failed_disk = i;
- break;
- }
- }
- /*
- * When we activate a spare disk we _must_ have a disk in
- * the lower (active) part of the array to replace.
- */
- if (failed_disk == -1) {
- MD_BUG();
- err = 1;
- goto abort;
- }
- /*
- * Find the spare disk ... (can only be in the 'high'
- * area of the array)
- */
- for (i = conf->raid_disks; i < MD_SB_DISKS; i++) {
- tmp = conf->multipaths + i;
- if (tmp->spare && tmp->number == (*d)->number) {
- spare_disk = i;
- break;
- }
- }
- if (spare_disk == -1) {
- MD_BUG();
- err = 1;
- goto abort;
- }
-
- sdisk = conf->multipaths + spare_disk;
- fdisk = conf->multipaths + failed_disk;
-
- spare_desc = &sb->disks[sdisk->number];
- failed_desc = &sb->disks[fdisk->number];
-
- if (spare_desc != *d || spare_desc->raid_disk != sdisk->raid_disk ||
- sdisk->raid_disk != spare_disk || fdisk->raid_disk != failed_disk ||
- failed_desc->raid_disk != fdisk->raid_disk) {
- MD_BUG();
- err = 1;
- goto abort;
- }
-
- /*
- * do the switch finally
- */
- spare_rdev = find_rdev_nr(mddev, spare_desc->number);
- failed_rdev = find_rdev_nr(mddev, failed_desc->number);
- xchg_values(spare_rdev->desc_nr, failed_rdev->desc_nr);
- spare_rdev->alias_device = 0;
- failed_rdev->alias_device = 1;
-
- xchg_values(*spare_desc, *failed_desc);
- xchg_values(*fdisk, *sdisk);
-
- /*
- * (careful, 'failed' and 'spare' are switched from now on)
- *
- * we want to preserve linear numbering and we want to
- * give the proper raid_disk number to the now activated
- * disk. (this means we switch back these values)
- */
-
- xchg_values(spare_desc->raid_disk, failed_desc->raid_disk);
- xchg_values(sdisk->raid_disk, fdisk->raid_disk);
- xchg_values(spare_desc->number, failed_desc->number);
- xchg_values(sdisk->number, fdisk->number);
-
- *d = failed_desc;
-
- if (!sdisk->bdev)
- sdisk->used_slot = 0;
- /*
- * this really activates the spare.
- */
- fdisk->spare = 0;
-
- /*
- * if we activate a spare, we definitely replace a
- * non-operational disk slot in the 'low' area of
- * the disk array.
- */
-
- conf->working_disks++;
-abort:
- spin_unlock_irq(&conf->device_lock);
-
- print_multipath_conf(conf);
- return err;
-}
static int multipath_add_disk(mddev_t *mddev, mdp_disk_t *added_desc,
mdk_rdev_t *rdev)
@@ -502,7 +305,7 @@ static int multipath_add_disk(mddev_t *m
print_multipath_conf(conf);
spin_lock_irq(&conf->device_lock);
- for (i = conf->raid_disks; i < MD_SB_DISKS; i++) {
+ for (i = 0; i < MD_SB_DISKS; i++) {
struct multipath_info *p = conf->multipaths + i;
if (!p->used_slot) {
if (added_desc->number != i)
@@ -510,10 +313,10 @@ static int multipath_add_disk(mddev_t *m
p->number = added_desc->number;
p->raid_disk = added_desc->raid_disk;
p->bdev = rdev->bdev;
- p->operational = 0;
- p->spare = 1;
+ p->operational = 1;
p->used_slot = 1;
conf->nr_disks++;
+ conf->working_disks++;
err = 0;
break;
}
@@ -543,8 +346,6 @@ static int multipath_remove_disk(mddev_t
err = -EBUSY;
goto abort;
}
- if (p->spare && i < conf->raid_disks)
- break;
p->bdev = NULL;
p->used_slot = 0;
conf->nr_disks--;
@@ -655,10 +456,10 @@ static int multipath_run (mddev_t *mddev
{
multipath_conf_t *conf;
int i, j, disk_idx;
- struct multipath_info *disk, *disk2;
+ struct multipath_info *disk;
mdp_super_t *sb = mddev->sb;
- mdp_disk_t *desc, *desc2;
- mdk_rdev_t *rdev, *def_rdev = NULL;
+ mdp_disk_t *desc;
+ mdk_rdev_t *rdev;
struct list_head *tmp;
int num_rdevs = 0;
@@ -709,69 +510,24 @@ static int multipath_run (mddev_t *mddev
printk(NOT_IN_SYNC, bdev_partition_name(rdev->bdev));
/*
- * Mark all disks as spare to start with, then pick our
- * active disk. If we have a disk that is marked active
- * in the sb, then use it, else use the first rdev.
+ * Mark all disks as active to start with, there are no
+ * spares. multipath_read_balance deals with choose
+ * the "best" operational device.
*/
disk->number = desc->number;
disk->raid_disk = desc->raid_disk;
disk->bdev = rdev->bdev;
- disk->operational = 0;
- disk->spare = 1;
+ disk->operational = 1;
disk->used_slot = 1;
mark_disk_sync(desc);
-
- if (disk_active(desc)) {
- if(!conf->working_disks) {
- printk(OPERATIONAL, bdev_partition_name(rdev->bdev),
- desc->raid_disk);
- disk->operational = 1;
- disk->spare = 0;
- conf->working_disks++;
- def_rdev = rdev;
- } else {
- mark_disk_spare(desc);
- }
- } else
- mark_disk_spare(desc);
-
- if(!num_rdevs++) def_rdev = rdev;
- }
- if(!conf->working_disks && num_rdevs) {
- desc = &sb->disks[def_rdev->desc_nr];
- disk = conf->multipaths + desc->raid_disk;
- printk(OPERATIONAL, bdev_partition_name(def_rdev->bdev),
- disk->raid_disk);
- disk->operational = 1;
- disk->spare = 0;
- conf->working_disks++;
mark_disk_active(desc);
+ num_rdevs++;
}
- /*
- * Make sure our active path is in desc spot 0
- */
- if(def_rdev->desc_nr != 0) {
- rdev = find_rdev_nr(mddev, 0);
- desc = &sb->disks[def_rdev->desc_nr];
- desc2 = sb->disks;
- disk = conf->multipaths + desc->raid_disk;
- disk2 = conf->multipaths + desc2->raid_disk;
- xchg_values(*desc2,*desc);
- xchg_values(*disk2,*disk);
- xchg_values(desc2->number, desc->number);
- xchg_values(disk2->number, disk->number);
- xchg_values(desc2->raid_disk, desc->raid_disk);
- xchg_values(disk2->raid_disk, disk->raid_disk);
- if(rdev) {
- xchg_values(def_rdev->desc_nr,rdev->desc_nr);
- } else {
- def_rdev->desc_nr = 0;
- }
- }
- conf->raid_disks = sb->raid_disks = sb->active_disks = 1;
+
+ conf->raid_disks = sb->raid_disks = sb->active_disks = num_rdevs;
conf->nr_disks = sb->nr_disks = sb->working_disks = num_rdevs;
sb->failed_disks = 0;
- sb->spare_disks = num_rdevs - 1;
+ sb->spare_disks = 0;
mddev->sb_dirty = 1;
conf->mddev = mddev;
conf->device_lock = SPIN_LOCK_UNLOCKED;
@@ -862,9 +618,6 @@ static mdk_personality_t multipath_perso
error_handler: multipath_error,
hot_add_disk: multipath_add_disk,
hot_remove_disk:multipath_remove_disk,
- spare_inactive: multipath_spare_inactive,
- spare_active: multipath_spare_active,
- spare_write: multipath_spare_write,
};
static int __init multipath_init (void)
--- ./include/linux/raid/multipath.h 2002/07/18 12:00:58 1.5
+++ ./include/linux/raid/multipath.h 2002/07/18 12:02:21 1.6
@@ -13,7 +13,6 @@ struct multipath_info {
* State bits:
*/
int operational;
- int spare;
int used_slot;
};
-
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