diff options
Diffstat (limited to 'drivers/md/dm-cache-policy-smq.c')
| -rw-r--r-- | drivers/md/dm-cache-policy-smq.c | 92 |
1 files changed, 85 insertions, 7 deletions
diff --git a/drivers/md/dm-cache-policy-smq.c b/drivers/md/dm-cache-policy-smq.c index 28d458674..cf48a617a 100644 --- a/drivers/md/dm-cache-policy-smq.c +++ b/drivers/md/dm-cache-policy-smq.c @@ -1567,8 +1567,48 @@ static void smq_tick(struct dm_cache_policy *p, bool can_block) spin_unlock_irqrestore(&mq->lock, flags); } +/* + * smq has no config values, but the old mq policy did. To avoid breaking + * software we continue to accept these configurables for the mq policy, + * but they have no effect. + */ +static int mq_set_config_value(struct dm_cache_policy *p, + const char *key, const char *value) +{ + unsigned long tmp; + + if (kstrtoul(value, 10, &tmp)) + return -EINVAL; + + if (!strcasecmp(key, "random_threshold") || + !strcasecmp(key, "sequential_threshold") || + !strcasecmp(key, "discard_promote_adjustment") || + !strcasecmp(key, "read_promote_adjustment") || + !strcasecmp(key, "write_promote_adjustment")) { + DMWARN("tunable '%s' no longer has any effect, mq policy is now an alias for smq", key); + return 0; + } + + return -EINVAL; +} + +static int mq_emit_config_values(struct dm_cache_policy *p, char *result, + unsigned maxlen, ssize_t *sz_ptr) +{ + ssize_t sz = *sz_ptr; + + DMEMIT("10 random_threshold 0 " + "sequential_threshold 0 " + "discard_promote_adjustment 0 " + "read_promote_adjustment 0 " + "write_promote_adjustment 0 "); + + *sz_ptr = sz; + return 0; +} + /* Init the policy plugin interface function pointers. */ -static void init_policy_functions(struct smq_policy *mq) +static void init_policy_functions(struct smq_policy *mq, bool mimic_mq) { mq->policy.destroy = smq_destroy; mq->policy.map = smq_map; @@ -1583,6 +1623,11 @@ static void init_policy_functions(struct smq_policy *mq) mq->policy.force_mapping = smq_force_mapping; mq->policy.residency = smq_residency; mq->policy.tick = smq_tick; + + if (mimic_mq) { + mq->policy.set_config_value = mq_set_config_value; + mq->policy.emit_config_values = mq_emit_config_values; + } } static bool too_many_hotspot_blocks(sector_t origin_size, @@ -1606,9 +1651,10 @@ static void calc_hotspot_params(sector_t origin_size, *hotspot_block_size /= 2u; } -static struct dm_cache_policy *smq_create(dm_cblock_t cache_size, - sector_t origin_size, - sector_t cache_block_size) +static struct dm_cache_policy *__smq_create(dm_cblock_t cache_size, + sector_t origin_size, + sector_t cache_block_size, + bool mimic_mq) { unsigned i; unsigned nr_sentinels_per_queue = 2u * NR_CACHE_LEVELS; @@ -1618,7 +1664,7 @@ static struct dm_cache_policy *smq_create(dm_cblock_t cache_size, if (!mq) return NULL; - init_policy_functions(mq); + init_policy_functions(mq, mimic_mq); mq->cache_size = cache_size; mq->cache_block_size = cache_block_size; @@ -1706,19 +1752,41 @@ bad_pool_init: return NULL; } +static struct dm_cache_policy *smq_create(dm_cblock_t cache_size, + sector_t origin_size, + sector_t cache_block_size) +{ + return __smq_create(cache_size, origin_size, cache_block_size, false); +} + +static struct dm_cache_policy *mq_create(dm_cblock_t cache_size, + sector_t origin_size, + sector_t cache_block_size) +{ + return __smq_create(cache_size, origin_size, cache_block_size, true); +} + /*----------------------------------------------------------------*/ static struct dm_cache_policy_type smq_policy_type = { .name = "smq", - .version = {1, 0, 0}, + .version = {1, 5, 0}, .hint_size = 4, .owner = THIS_MODULE, .create = smq_create }; +static struct dm_cache_policy_type mq_policy_type = { + .name = "mq", + .version = {1, 5, 0}, + .hint_size = 4, + .owner = THIS_MODULE, + .create = mq_create, +}; + static struct dm_cache_policy_type default_policy_type = { .name = "default", - .version = {1, 4, 0}, + .version = {1, 5, 0}, .hint_size = 4, .owner = THIS_MODULE, .create = smq_create, @@ -1735,9 +1803,17 @@ static int __init smq_init(void) return -ENOMEM; } + r = dm_cache_policy_register(&mq_policy_type); + if (r) { + DMERR("register failed (as mq) %d", r); + dm_cache_policy_unregister(&smq_policy_type); + return -ENOMEM; + } + r = dm_cache_policy_register(&default_policy_type); if (r) { DMERR("register failed (as default) %d", r); + dm_cache_policy_unregister(&mq_policy_type); dm_cache_policy_unregister(&smq_policy_type); return -ENOMEM; } @@ -1748,6 +1824,7 @@ static int __init smq_init(void) static void __exit smq_exit(void) { dm_cache_policy_unregister(&smq_policy_type); + dm_cache_policy_unregister(&mq_policy_type); dm_cache_policy_unregister(&default_policy_type); } @@ -1759,3 +1836,4 @@ MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("smq cache policy"); MODULE_ALIAS("dm-cache-default"); +MODULE_ALIAS("dm-cache-mq"); |