Commit 7c7546cc authored by NeilBrown's avatar NeilBrown Committed by Linus Torvalds

[PATCH] md: allow a linear array to have drives added while active

Signed-off-by: default avatarNeil Brown <neilb@suse.de>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 5fd6c1dc
......@@ -111,7 +111,7 @@ static int linear_issue_flush(request_queue_t *q, struct gendisk *disk,
return ret;
}
static int linear_run (mddev_t *mddev)
static linear_conf_t *linear_conf(mddev_t *mddev, int raid_disks)
{
linear_conf_t *conf;
dev_info_t **table;
......@@ -121,20 +121,21 @@ static int linear_run (mddev_t *mddev)
sector_t curr_offset;
struct list_head *tmp;
conf = kzalloc (sizeof (*conf) + mddev->raid_disks*sizeof(dev_info_t),
conf = kzalloc (sizeof (*conf) + raid_disks*sizeof(dev_info_t),
GFP_KERNEL);
if (!conf)
goto out;
return NULL;
mddev->private = conf;
cnt = 0;
mddev->array_size = 0;
conf->array_size = 0;
ITERATE_RDEV(mddev,rdev,tmp) {
int j = rdev->raid_disk;
dev_info_t *disk = conf->disks + j;
if (j < 0 || j > mddev->raid_disks || disk->rdev) {
if (j < 0 || j > raid_disks || disk->rdev) {
printk("linear: disk numbering problem. Aborting!\n");
goto out;
}
......@@ -152,11 +153,11 @@ static int linear_run (mddev_t *mddev)
blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
disk->size = rdev->size;
mddev->array_size += rdev->size;
conf->array_size += rdev->size;
cnt++;
}
if (cnt != mddev->raid_disks) {
if (cnt != raid_disks) {
printk("linear: not enough drives present. Aborting!\n");
goto out;
}
......@@ -200,7 +201,7 @@ static int linear_run (mddev_t *mddev)
unsigned round;
unsigned long base;
sz = mddev->array_size >> conf->preshift;
sz = conf->array_size >> conf->preshift;
sz += 1; /* force round-up */
base = conf->hash_spacing >> conf->preshift;
round = sector_div(sz, base);
......@@ -247,14 +248,56 @@ static int linear_run (mddev_t *mddev)
BUG_ON(table - conf->hash_table > nb_zone);
return conf;
out:
kfree(conf);
return NULL;
}
static int linear_run (mddev_t *mddev)
{
linear_conf_t *conf;
conf = linear_conf(mddev, mddev->raid_disks);
if (!conf)
return 1;
mddev->private = conf;
mddev->array_size = conf->array_size;
blk_queue_merge_bvec(mddev->queue, linear_mergeable_bvec);
mddev->queue->unplug_fn = linear_unplug;
mddev->queue->issue_flush_fn = linear_issue_flush;
return 0;
}
out:
kfree(conf);
return 1;
static int linear_add(mddev_t *mddev, mdk_rdev_t *rdev)
{
/* Adding a drive to a linear array allows the array to grow.
* It is permitted if the new drive has a matching superblock
* already on it, with raid_disk equal to raid_disks.
* It is achieved by creating a new linear_private_data structure
* and swapping it in in-place of the current one.
* The current one is never freed until the array is stopped.
* This avoids races.
*/
linear_conf_t *newconf;
if (rdev->raid_disk != mddev->raid_disks)
return -EINVAL;
newconf = linear_conf(mddev,mddev->raid_disks+1);
if (!newconf)
return -ENOMEM;
newconf->prev = mddev_to_conf(mddev);
mddev->private = newconf;
mddev->raid_disks++;
mddev->array_size = newconf->array_size;
set_capacity(mddev->gendisk, mddev->array_size << 1);
return 0;
}
static int linear_stop (mddev_t *mddev)
......@@ -262,8 +305,12 @@ static int linear_stop (mddev_t *mddev)
linear_conf_t *conf = mddev_to_conf(mddev);
blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/
kfree(conf->hash_table);
kfree(conf);
do {
linear_conf_t *t = conf->prev;
kfree(conf->hash_table);
kfree(conf);
conf = t;
} while (conf);
return 0;
}
......@@ -360,6 +407,7 @@ static struct mdk_personality linear_personality =
.run = linear_run,
.stop = linear_stop,
.status = linear_status,
.hot_add_disk = linear_add,
};
static int __init linear_init (void)
......
......@@ -817,8 +817,8 @@ static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev)
if (desc->state & (1<<MD_DISK_FAULTY))
set_bit(Faulty, &rdev->flags);
else if (desc->state & (1<<MD_DISK_SYNC) &&
desc->raid_disk < mddev->raid_disks) {
else if (desc->state & (1<<MD_DISK_SYNC) /* &&
desc->raid_disk < mddev->raid_disks */) {
set_bit(In_sync, &rdev->flags);
rdev->raid_disk = desc->raid_disk;
}
......@@ -3359,6 +3359,17 @@ static int add_new_disk(mddev_t * mddev, mdu_disk_info_t *info)
rdev->raid_disk = -1;
err = bind_rdev_to_array(rdev, mddev);
if (!err && !mddev->pers->hot_remove_disk) {
/* If there is hot_add_disk but no hot_remove_disk
* then added disks for geometry changes,
* and should be added immediately.
*/
super_types[mddev->major_version].
validate_super(mddev, rdev);
err = mddev->pers->hot_add_disk(mddev, rdev);
if (err)
unbind_rdev_from_array(rdev);
}
if (err)
export_rdev(rdev);
......
......@@ -13,8 +13,10 @@ typedef struct dev_info dev_info_t;
struct linear_private_data
{
struct linear_private_data *prev; /* earlier version */
dev_info_t **hash_table;
sector_t hash_spacing;
sector_t array_size;
int preshift; /* shift before dividing by hash_spacing */
dev_info_t disks[0];
};
......
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