summaryrefslogtreecommitdiff
path: root/drivers/md/raid5.c
diff options
context:
space:
mode:
authorArtur Paszkiewicz <artur.paszkiewicz@intel.com>2017-03-09 10:00:03 +0100
committerShaohua Li <shli@fb.com>2017-03-16 16:55:56 -0700
commitba903a3ea465bd2f2bb9316054b295e79a7a518e (patch)
tree9eae9199e526deaa23791d7477bffcd910dbe463 /drivers/md/raid5.c
parent6358c239d88c751a9f14152a8d4ad2b69f5be48f (diff)
raid5-ppl: runtime PPL enabling or disabling
Allow writing to 'consistency_policy' attribute when the array is active. Add a new function 'change_consistency_policy' to the md_personality operations structure to handle the change in the personality code. Values "ppl" and "resync" are accepted and turn PPL on and off respectively. When enabling PPL its location and size should first be set using 'ppl_sector' and 'ppl_size' attributes and a valid PPL header should be written at this location on each member device. Enabling or disabling PPL is performed under a suspended array. The raid5_reset_stripe_cache function frees the stripe cache and allocates it again in order to allocate or free the ppl_pages for the stripes in the stripe cache. Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com> Signed-off-by: Shaohua Li <shli@fb.com>
Diffstat (limited to 'drivers/md/raid5.c')
-rw-r--r--drivers/md/raid5.c53
1 files changed, 53 insertions, 0 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 6760af251864..88cc8981bd49 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -8334,6 +8334,58 @@ static void *raid6_takeover(struct mddev *mddev)
return setup_conf(mddev);
}
+static void raid5_reset_stripe_cache(struct mddev *mddev)
+{
+ struct r5conf *conf = mddev->private;
+
+ mutex_lock(&conf->cache_size_mutex);
+ while (conf->max_nr_stripes &&
+ drop_one_stripe(conf))
+ ;
+ while (conf->min_nr_stripes > conf->max_nr_stripes &&
+ grow_one_stripe(conf, GFP_KERNEL))
+ ;
+ mutex_unlock(&conf->cache_size_mutex);
+}
+
+static int raid5_change_consistency_policy(struct mddev *mddev, const char *buf)
+{
+ struct r5conf *conf;
+ int err;
+
+ err = mddev_lock(mddev);
+ if (err)
+ return err;
+ conf = mddev->private;
+ if (!conf) {
+ mddev_unlock(mddev);
+ return -ENODEV;
+ }
+
+ if (strncmp(buf, "ppl", 3) == 0 && !raid5_has_ppl(conf)) {
+ mddev_suspend(mddev);
+ set_bit(MD_HAS_PPL, &mddev->flags);
+ err = log_init(conf, NULL);
+ if (!err)
+ raid5_reset_stripe_cache(mddev);
+ mddev_resume(mddev);
+ } else if (strncmp(buf, "resync", 6) == 0 && raid5_has_ppl(conf)) {
+ mddev_suspend(mddev);
+ log_exit(conf);
+ raid5_reset_stripe_cache(mddev);
+ mddev_resume(mddev);
+ } else {
+ err = -EINVAL;
+ }
+
+ if (!err)
+ md_update_sb(mddev, 1);
+
+ mddev_unlock(mddev);
+
+ return err;
+}
+
static struct md_personality raid6_personality =
{
.name = "raid6",
@@ -8379,6 +8431,7 @@ static struct md_personality raid5_personality =
.quiesce = raid5_quiesce,
.takeover = raid5_takeover,
.congested = raid5_congested,
+ .change_consistency_policy = raid5_change_consistency_policy,
};
static struct md_personality raid4_personality =