mirror of
https://github.com/team-infusion-developers/android_kernel_samsung_msm8976.git
synced 2024-11-01 02:21:16 +00:00
Allow devices that hold metadata for the device-mapper thin
provisioning target to be extended easily; allow WRITE SAME on multipath devices; an assortment of little fixes and clean-ups. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQIcBAABAgAGBQJRjPh5AAoJEK2W1qbAHj1nznsP/idIXjHebZbyp0DHLIHcOyR9 R7wj641TCE72qtIvlxPkpqrFdPQF5alilerS3OpWfrOR5clswQhI8aZOfdXRtvCe 3QQ2yLpi1aZxm/TjJXo4vlfm+JJQZVsytG+5ou5cNPVt0/rAAhaMS3n2OvSNBiMO krtksMZk8oD0LV33M6FLnieV5gZIsEpy1VrPu8eLfTT7cSE28k7h0wsN8MzRlRKq uKThwPkA332N9adPZoxr3diRL7USSn6VYo9ygheJfAj5o6UGDxwZZu2BnO0vsaEj 6q9yt+W6wFa96knBI7pVb19OEtNYvF7fjsYuAu0DRvEZ8cPeU40Mi/fNnN8TAg+Q tFZkZ+rlvQCBylIsGEhLZkOjTf9cl2H9I3BfVLQ2givwANLvUjunGtcxPENbsKSq kKBwlXyDs2bgUIk1ltTTyenGZxVA7ADOPNbvYMOKWzeh8gsKgQN+34ggzhHYgNQr jkljEt3ToPDQ+rqWmz5+NGNTzH6I0FuK/rF9C9TAaFnBgCAuXvfNEUYBR0VnXgp+ LxijQ+q1CFDNC7pnrlVrKz2UAlpn2dDVJsREMUXZQQr4r06x3TgmMaLcGpUgNK0Q iZ1vHPkHMmFTeCyJYJpe62wKRDQotevhjcgyQAEJBiPFOyVcfAn/WqPRz6U/IP00 A1QR9eBvCWKrcZnYOet9 =YXMj -----END PGP SIGNATURE----- Merge tag 'dm-3.10-changes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm Pull device-mapper updates from Alasdair Kergon: "Allow devices that hold metadata for the device-mapper thin provisioning target to be extended easily; allow WRITE SAME on multipath devices; an assortment of little fixes and clean-ups." * tag 'dm-3.10-changes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm: (21 commits) dm cache: set config value dm cache: move config fns dm thin: generate event when metadata threshold passed dm persistent metadata: add space map threshold callback dm persistent data: add threshold callback to space map dm thin: detect metadata device resizing dm persistent data: support space map resizing dm thin: open dev read only when possible dm thin: refactor data dev resize dm cache: replace memcpy with struct assignment dm cache: fix typos in comments dm cache policy: fix description of lookup fn dm: document iterate_devices dm persistent data: fix error message typos dm cache: tune migration throttling dm mpath: enable WRITE SAME support dm table: fix write same support dm bufio: avoid a possible __vmalloc deadlock dm snapshot: fix error return code in snapshot_ctr dm cache: fix error return code in cache_create ...
This commit is contained in:
Linus Torvalds
commit
ec6671589a
15 changed files with 445 additions and 119 deletions
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|
@ -319,6 +319,9 @@ static void __cache_size_refresh(void)
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static void *alloc_buffer_data(struct dm_bufio_client *c, gfp_t gfp_mask,
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enum data_mode *data_mode)
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{
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unsigned noio_flag;
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void *ptr;
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if (c->block_size <= DM_BUFIO_BLOCK_SIZE_SLAB_LIMIT) {
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*data_mode = DATA_MODE_SLAB;
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return kmem_cache_alloc(DM_BUFIO_CACHE(c), gfp_mask);
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@ -332,7 +335,26 @@ static void *alloc_buffer_data(struct dm_bufio_client *c, gfp_t gfp_mask,
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}
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*data_mode = DATA_MODE_VMALLOC;
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return __vmalloc(c->block_size, gfp_mask, PAGE_KERNEL);
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/*
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* __vmalloc allocates the data pages and auxiliary structures with
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* gfp_flags that were specified, but pagetables are always allocated
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* with GFP_KERNEL, no matter what was specified as gfp_mask.
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*
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* Consequently, we must set per-process flag PF_MEMALLOC_NOIO so that
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* all allocations done by this process (including pagetables) are done
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* as if GFP_NOIO was specified.
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*/
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if (gfp_mask & __GFP_NORETRY)
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noio_flag = memalloc_noio_save();
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ptr = __vmalloc(c->block_size, gfp_mask, PAGE_KERNEL);
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if (gfp_mask & __GFP_NORETRY)
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memalloc_noio_restore(noio_flag);
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return ptr;
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}
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/*
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@ -1044,7 +1044,7 @@ void dm_cache_metadata_get_stats(struct dm_cache_metadata *cmd,
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struct dm_cache_statistics *stats)
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{
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down_read(&cmd->root_lock);
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memcpy(stats, &cmd->stats, sizeof(*stats));
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*stats = cmd->stats;
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up_read(&cmd->root_lock);
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}
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@ -1052,7 +1052,7 @@ void dm_cache_metadata_set_stats(struct dm_cache_metadata *cmd,
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struct dm_cache_statistics *stats)
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{
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down_write(&cmd->root_lock);
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memcpy(&cmd->stats, stats, sizeof(*stats));
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cmd->stats = *stats;
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up_write(&cmd->root_lock);
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}
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@ -130,8 +130,8 @@ struct dm_cache_policy {
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*
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* Must not block.
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*
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* Returns 1 iff in cache, 0 iff not, < 0 on error (-EWOULDBLOCK
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* would be typical).
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* Returns 0 if in cache, -ENOENT if not, < 0 for other errors
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* (-EWOULDBLOCK would be typical).
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*/
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int (*lookup)(struct dm_cache_policy *p, dm_oblock_t oblock, dm_cblock_t *cblock);
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@ -205,7 +205,7 @@ struct per_bio_data {
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/*
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* writethrough fields. These MUST remain at the end of this
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* structure and the 'cache' member must be the first as it
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* is used to determine the offsetof the writethrough fields.
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* is used to determine the offset of the writethrough fields.
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*/
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struct cache *cache;
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dm_cblock_t cblock;
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@ -393,7 +393,7 @@ static int get_cell(struct cache *cache,
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return r;
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}
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/*----------------------------------------------------------------*/
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/*----------------------------------------------------------------*/
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static bool is_dirty(struct cache *cache, dm_cblock_t b)
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{
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@ -419,6 +419,7 @@ static void clear_dirty(struct cache *cache, dm_oblock_t oblock, dm_cblock_t cbl
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}
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/*----------------------------------------------------------------*/
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static bool block_size_is_power_of_two(struct cache *cache)
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{
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return cache->sectors_per_block_shift >= 0;
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@ -667,7 +668,7 @@ static void writethrough_endio(struct bio *bio, int err)
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/*
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* We can't issue this bio directly, since we're in interrupt
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* context. So it get's put on a bio list for processing by the
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* context. So it gets put on a bio list for processing by the
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* worker thread.
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*/
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defer_writethrough_bio(pb->cache, bio);
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@ -1445,6 +1446,7 @@ static void do_worker(struct work_struct *ws)
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static void do_waker(struct work_struct *ws)
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{
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struct cache *cache = container_of(to_delayed_work(ws), struct cache, waker);
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policy_tick(cache->policy);
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wake_worker(cache);
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queue_delayed_work(cache->wq, &cache->waker, COMMIT_PERIOD);
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}
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@ -1809,7 +1811,37 @@ static int parse_cache_args(struct cache_args *ca, int argc, char **argv,
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static struct kmem_cache *migration_cache;
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static int set_config_values(struct dm_cache_policy *p, int argc, const char **argv)
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#define NOT_CORE_OPTION 1
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static int process_config_option(struct cache *cache, const char *key, const char *value)
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{
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unsigned long tmp;
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if (!strcasecmp(key, "migration_threshold")) {
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if (kstrtoul(value, 10, &tmp))
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return -EINVAL;
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cache->migration_threshold = tmp;
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return 0;
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}
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return NOT_CORE_OPTION;
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}
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static int set_config_value(struct cache *cache, const char *key, const char *value)
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{
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int r = process_config_option(cache, key, value);
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if (r == NOT_CORE_OPTION)
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r = policy_set_config_value(cache->policy, key, value);
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if (r)
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DMWARN("bad config value for %s: %s", key, value);
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return r;
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}
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static int set_config_values(struct cache *cache, int argc, const char **argv)
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{
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int r = 0;
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@ -1819,12 +1851,9 @@ static int set_config_values(struct dm_cache_policy *p, int argc, const char **a
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}
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while (argc) {
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r = policy_set_config_value(p, argv[0], argv[1]);
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if (r) {
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DMWARN("policy_set_config_value failed: key = '%s', value = '%s'",
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argv[0], argv[1]);
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return r;
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}
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r = set_config_value(cache, argv[0], argv[1]);
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if (r)
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break;
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argc -= 2;
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argv += 2;
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@ -1836,8 +1865,6 @@ static int set_config_values(struct dm_cache_policy *p, int argc, const char **a
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static int create_cache_policy(struct cache *cache, struct cache_args *ca,
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char **error)
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{
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int r;
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cache->policy = dm_cache_policy_create(ca->policy_name,
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cache->cache_size,
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cache->origin_sectors,
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@ -1847,14 +1874,7 @@ static int create_cache_policy(struct cache *cache, struct cache_args *ca,
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return -ENOMEM;
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}
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r = set_config_values(cache->policy, ca->policy_argc, ca->policy_argv);
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if (r) {
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*error = "Error setting cache policy's config values";
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dm_cache_policy_destroy(cache->policy);
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cache->policy = NULL;
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}
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return r;
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return 0;
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}
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/*
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@ -1886,7 +1906,7 @@ static sector_t calculate_discard_block_size(sector_t cache_block_size,
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return discard_block_size;
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}
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#define DEFAULT_MIGRATION_THRESHOLD (2048 * 100)
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#define DEFAULT_MIGRATION_THRESHOLD 2048
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static int cache_create(struct cache_args *ca, struct cache **result)
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{
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@ -1911,7 +1931,7 @@ static int cache_create(struct cache_args *ca, struct cache **result)
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ti->discards_supported = true;
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ti->discard_zeroes_data_unsupported = true;
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memcpy(&cache->features, &ca->features, sizeof(cache->features));
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cache->features = ca->features;
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ti->per_bio_data_size = get_per_bio_data_size(cache);
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cache->callbacks.congested_fn = cache_is_congested;
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@ -1948,7 +1968,15 @@ static int cache_create(struct cache_args *ca, struct cache **result)
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r = create_cache_policy(cache, ca, error);
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if (r)
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goto bad;
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cache->policy_nr_args = ca->policy_argc;
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cache->migration_threshold = DEFAULT_MIGRATION_THRESHOLD;
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r = set_config_values(cache, ca->policy_argc, ca->policy_argv);
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if (r) {
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*error = "Error setting cache policy's config values";
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goto bad;
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}
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cmd = dm_cache_metadata_open(cache->metadata_dev->bdev,
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ca->block_size, may_format,
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@ -1967,10 +1995,10 @@ static int cache_create(struct cache_args *ca, struct cache **result)
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INIT_LIST_HEAD(&cache->quiesced_migrations);
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INIT_LIST_HEAD(&cache->completed_migrations);
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INIT_LIST_HEAD(&cache->need_commit_migrations);
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cache->migration_threshold = DEFAULT_MIGRATION_THRESHOLD;
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atomic_set(&cache->nr_migrations, 0);
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init_waitqueue_head(&cache->migration_wait);
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r = -ENOMEM;
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cache->nr_dirty = 0;
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cache->dirty_bitset = alloc_bitset(from_cblock(cache->cache_size));
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if (!cache->dirty_bitset) {
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@ -2517,23 +2545,6 @@ err:
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DMEMIT("Error");
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}
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#define NOT_CORE_OPTION 1
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static int process_config_option(struct cache *cache, char **argv)
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{
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unsigned long tmp;
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if (!strcasecmp(argv[0], "migration_threshold")) {
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if (kstrtoul(argv[1], 10, &tmp))
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return -EINVAL;
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cache->migration_threshold = tmp;
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return 0;
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}
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return NOT_CORE_OPTION;
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}
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/*
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* Supports <key> <value>.
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*
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@ -2541,17 +2552,12 @@ static int process_config_option(struct cache *cache, char **argv)
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*/
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static int cache_message(struct dm_target *ti, unsigned argc, char **argv)
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{
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int r;
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struct cache *cache = ti->private;
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if (argc != 2)
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return -EINVAL;
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r = process_config_option(cache, argv);
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if (r == NOT_CORE_OPTION)
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return policy_set_config_value(cache->policy, argv[0], argv[1]);
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return r;
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return set_config_value(cache, argv[0], argv[1]);
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}
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static int cache_iterate_devices(struct dm_target *ti,
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@ -2609,7 +2615,7 @@ static void cache_io_hints(struct dm_target *ti, struct queue_limits *limits)
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static struct target_type cache_target = {
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.name = "cache",
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.version = {1, 1, 0},
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.version = {1, 1, 1},
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.module = THIS_MODULE,
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.ctr = cache_ctr,
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.dtr = cache_dtr,
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|
|
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@ -907,6 +907,7 @@ static int multipath_ctr(struct dm_target *ti, unsigned int argc,
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ti->num_flush_bios = 1;
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ti->num_discard_bios = 1;
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ti->num_write_same_bios = 1;
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return 0;
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|
|
|
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|
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@ -1121,6 +1121,7 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv)
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s->pending_pool = mempool_create_slab_pool(MIN_IOS, pending_cache);
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if (!s->pending_pool) {
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ti->error = "Could not allocate mempool for pending exceptions";
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r = -ENOMEM;
|
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goto bad_pending_pool;
|
||||
}
|
||||
|
||||
|
|
|
|||
|
|
@ -94,7 +94,7 @@ static int get_stripe(struct dm_target *ti, struct stripe_c *sc,
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|||
static int stripe_ctr(struct dm_target *ti, unsigned int argc, char **argv)
|
||||
{
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||||
struct stripe_c *sc;
|
||||
sector_t width;
|
||||
sector_t width, tmp_len;
|
||||
uint32_t stripes;
|
||||
uint32_t chunk_size;
|
||||
int r;
|
||||
|
|
@ -116,18 +116,19 @@ static int stripe_ctr(struct dm_target *ti, unsigned int argc, char **argv)
|
|||
}
|
||||
|
||||
width = ti->len;
|
||||
if (sector_div(width, chunk_size)) {
|
||||
ti->error = "Target length not divisible by "
|
||||
"chunk size";
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
if (sector_div(width, stripes)) {
|
||||
ti->error = "Target length not divisible by "
|
||||
"number of stripes";
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
tmp_len = width;
|
||||
if (sector_div(tmp_len, chunk_size)) {
|
||||
ti->error = "Target length not divisible by "
|
||||
"chunk size";
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
/*
|
||||
* Do we have enough arguments for that many stripes ?
|
||||
*/
|
||||
|
|
|
|||
|
|
@ -1442,7 +1442,7 @@ static bool dm_table_supports_write_same(struct dm_table *t)
|
|||
return false;
|
||||
|
||||
if (!ti->type->iterate_devices ||
|
||||
!ti->type->iterate_devices(ti, device_not_write_same_capable, NULL))
|
||||
ti->type->iterate_devices(ti, device_not_write_same_capable, NULL))
|
||||
return false;
|
||||
}
|
||||
|
||||
|
|
|
|||
|
|
@ -1645,12 +1645,12 @@ int dm_thin_get_highest_mapped_block(struct dm_thin_device *td,
|
|||
return r;
|
||||
}
|
||||
|
||||
static int __resize_data_dev(struct dm_pool_metadata *pmd, dm_block_t new_count)
|
||||
static int __resize_space_map(struct dm_space_map *sm, dm_block_t new_count)
|
||||
{
|
||||
int r;
|
||||
dm_block_t old_count;
|
||||
|
||||
r = dm_sm_get_nr_blocks(pmd->data_sm, &old_count);
|
||||
r = dm_sm_get_nr_blocks(sm, &old_count);
|
||||
if (r)
|
||||
return r;
|
||||
|
||||
|
|
@ -1658,11 +1658,11 @@ static int __resize_data_dev(struct dm_pool_metadata *pmd, dm_block_t new_count)
|
|||
return 0;
|
||||
|
||||
if (new_count < old_count) {
|
||||
DMERR("cannot reduce size of data device");
|
||||
DMERR("cannot reduce size of space map");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
return dm_sm_extend(pmd->data_sm, new_count - old_count);
|
||||
return dm_sm_extend(sm, new_count - old_count);
|
||||
}
|
||||
|
||||
int dm_pool_resize_data_dev(struct dm_pool_metadata *pmd, dm_block_t new_count)
|
||||
|
|
@ -1671,7 +1671,19 @@ int dm_pool_resize_data_dev(struct dm_pool_metadata *pmd, dm_block_t new_count)
|
|||
|
||||
down_write(&pmd->root_lock);
|
||||
if (!pmd->fail_io)
|
||||
r = __resize_data_dev(pmd, new_count);
|
||||
r = __resize_space_map(pmd->data_sm, new_count);
|
||||
up_write(&pmd->root_lock);
|
||||
|
||||
return r;
|
||||
}
|
||||
|
||||
int dm_pool_resize_metadata_dev(struct dm_pool_metadata *pmd, dm_block_t new_count)
|
||||
{
|
||||
int r = -EINVAL;
|
||||
|
||||
down_write(&pmd->root_lock);
|
||||
if (!pmd->fail_io)
|
||||
r = __resize_space_map(pmd->metadata_sm, new_count);
|
||||
up_write(&pmd->root_lock);
|
||||
|
||||
return r;
|
||||
|
|
@ -1684,3 +1696,17 @@ void dm_pool_metadata_read_only(struct dm_pool_metadata *pmd)
|
|||
dm_bm_set_read_only(pmd->bm);
|
||||
up_write(&pmd->root_lock);
|
||||
}
|
||||
|
||||
int dm_pool_register_metadata_threshold(struct dm_pool_metadata *pmd,
|
||||
dm_block_t threshold,
|
||||
dm_sm_threshold_fn fn,
|
||||
void *context)
|
||||
{
|
||||
int r;
|
||||
|
||||
down_write(&pmd->root_lock);
|
||||
r = dm_sm_register_threshold_callback(pmd->metadata_sm, threshold, fn, context);
|
||||
up_write(&pmd->root_lock);
|
||||
|
||||
return r;
|
||||
}
|
||||
|
|
|
|||
|
|
@ -8,6 +8,7 @@
|
|||
#define DM_THIN_METADATA_H
|
||||
|
||||
#include "persistent-data/dm-block-manager.h"
|
||||
#include "persistent-data/dm-space-map.h"
|
||||
|
||||
#define THIN_METADATA_BLOCK_SIZE 4096
|
||||
|
||||
|
|
@ -185,6 +186,7 @@ int dm_pool_get_data_dev_size(struct dm_pool_metadata *pmd, dm_block_t *result);
|
|||
* blocks would be lost.
|
||||
*/
|
||||
int dm_pool_resize_data_dev(struct dm_pool_metadata *pmd, dm_block_t new_size);
|
||||
int dm_pool_resize_metadata_dev(struct dm_pool_metadata *pmd, dm_block_t new_size);
|
||||
|
||||
/*
|
||||
* Flicks the underlying block manager into read only mode, so you know
|
||||
|
|
@ -192,6 +194,11 @@ int dm_pool_resize_data_dev(struct dm_pool_metadata *pmd, dm_block_t new_size);
|
|||
*/
|
||||
void dm_pool_metadata_read_only(struct dm_pool_metadata *pmd);
|
||||
|
||||
int dm_pool_register_metadata_threshold(struct dm_pool_metadata *pmd,
|
||||
dm_block_t threshold,
|
||||
dm_sm_threshold_fn fn,
|
||||
void *context);
|
||||
|
||||
/*----------------------------------------------------------------*/
|
||||
|
||||
#endif
|
||||
|
|
|
|||
|
|
@ -922,7 +922,7 @@ static int alloc_data_block(struct thin_c *tc, dm_block_t *result)
|
|||
return r;
|
||||
|
||||
if (free_blocks <= pool->low_water_blocks && !pool->low_water_triggered) {
|
||||
DMWARN("%s: reached low water mark, sending event.",
|
||||
DMWARN("%s: reached low water mark for data device: sending event.",
|
||||
dm_device_name(pool->pool_md));
|
||||
spin_lock_irqsave(&pool->lock, flags);
|
||||
pool->low_water_triggered = 1;
|
||||
|
|
@ -1281,6 +1281,10 @@ static void process_bio_fail(struct thin_c *tc, struct bio *bio)
|
|||
bio_io_error(bio);
|
||||
}
|
||||
|
||||
/*
|
||||
* FIXME: should we also commit due to size of transaction, measured in
|
||||
* metadata blocks?
|
||||
*/
|
||||
static int need_commit_due_to_time(struct pool *pool)
|
||||
{
|
||||
return jiffies < pool->last_commit_jiffies ||
|
||||
|
|
@ -1909,6 +1913,56 @@ static int parse_pool_features(struct dm_arg_set *as, struct pool_features *pf,
|
|||
return r;
|
||||
}
|
||||
|
||||
static void metadata_low_callback(void *context)
|
||||
{
|
||||
struct pool *pool = context;
|
||||
|
||||
DMWARN("%s: reached low water mark for metadata device: sending event.",
|
||||
dm_device_name(pool->pool_md));
|
||||
|
||||
dm_table_event(pool->ti->table);
|
||||
}
|
||||
|
||||
static sector_t get_metadata_dev_size(struct block_device *bdev)
|
||||
{
|
||||
sector_t metadata_dev_size = i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
|
||||
char buffer[BDEVNAME_SIZE];
|
||||
|
||||
if (metadata_dev_size > THIN_METADATA_MAX_SECTORS_WARNING) {
|
||||
DMWARN("Metadata device %s is larger than %u sectors: excess space will not be used.",
|
||||
bdevname(bdev, buffer), THIN_METADATA_MAX_SECTORS);
|
||||
metadata_dev_size = THIN_METADATA_MAX_SECTORS_WARNING;
|
||||
}
|
||||
|
||||
return metadata_dev_size;
|
||||
}
|
||||
|
||||
static dm_block_t get_metadata_dev_size_in_blocks(struct block_device *bdev)
|
||||
{
|
||||
sector_t metadata_dev_size = get_metadata_dev_size(bdev);
|
||||
|
||||
sector_div(metadata_dev_size, THIN_METADATA_BLOCK_SIZE >> SECTOR_SHIFT);
|
||||
|
||||
return metadata_dev_size;
|
||||
}
|
||||
|
||||
/*
|
||||
* When a metadata threshold is crossed a dm event is triggered, and
|
||||
* userland should respond by growing the metadata device. We could let
|
||||
* userland set the threshold, like we do with the data threshold, but I'm
|
||||
* not sure they know enough to do this well.
|
||||
*/
|
||||
static dm_block_t calc_metadata_threshold(struct pool_c *pt)
|
||||
{
|
||||
/*
|
||||
* 4M is ample for all ops with the possible exception of thin
|
||||
* device deletion which is harmless if it fails (just retry the
|
||||
* delete after you've grown the device).
|
||||
*/
|
||||
dm_block_t quarter = get_metadata_dev_size_in_blocks(pt->metadata_dev->bdev) / 4;
|
||||
return min((dm_block_t)1024ULL /* 4M */, quarter);
|
||||
}
|
||||
|
||||
/*
|
||||
* thin-pool <metadata dev> <data dev>
|
||||
* <data block size (sectors)>
|
||||
|
|
@ -1931,8 +1985,7 @@ static int pool_ctr(struct dm_target *ti, unsigned argc, char **argv)
|
|||
unsigned long block_size;
|
||||
dm_block_t low_water_blocks;
|
||||
struct dm_dev *metadata_dev;
|
||||
sector_t metadata_dev_size;
|
||||
char b[BDEVNAME_SIZE];
|
||||
fmode_t metadata_mode;
|
||||
|
||||
/*
|
||||
* FIXME Remove validation from scope of lock.
|
||||
|
|
@ -1944,19 +1997,32 @@ static int pool_ctr(struct dm_target *ti, unsigned argc, char **argv)
|
|||
r = -EINVAL;
|
||||
goto out_unlock;
|
||||
}
|
||||
|
||||
as.argc = argc;
|
||||
as.argv = argv;
|
||||
|
||||
r = dm_get_device(ti, argv[0], FMODE_READ | FMODE_WRITE, &metadata_dev);
|
||||
/*
|
||||
* Set default pool features.
|
||||
*/
|
||||
pool_features_init(&pf);
|
||||
|
||||
dm_consume_args(&as, 4);
|
||||
r = parse_pool_features(&as, &pf, ti);
|
||||
if (r)
|
||||
goto out_unlock;
|
||||
|
||||
metadata_mode = FMODE_READ | ((pf.mode == PM_READ_ONLY) ? 0 : FMODE_WRITE);
|
||||
r = dm_get_device(ti, argv[0], metadata_mode, &metadata_dev);
|
||||
if (r) {
|
||||
ti->error = "Error opening metadata block device";
|
||||
goto out_unlock;
|
||||
}
|
||||
|
||||
metadata_dev_size = i_size_read(metadata_dev->bdev->bd_inode) >> SECTOR_SHIFT;
|
||||
if (metadata_dev_size > THIN_METADATA_MAX_SECTORS_WARNING)
|
||||
DMWARN("Metadata device %s is larger than %u sectors: excess space will not be used.",
|
||||
bdevname(metadata_dev->bdev, b), THIN_METADATA_MAX_SECTORS);
|
||||
/*
|
||||
* Run for the side-effect of possibly issuing a warning if the
|
||||
* device is too big.
|
||||
*/
|
||||
(void) get_metadata_dev_size(metadata_dev->bdev);
|
||||
|
||||
r = dm_get_device(ti, argv[1], FMODE_READ | FMODE_WRITE, &data_dev);
|
||||
if (r) {
|
||||
|
|
@ -1979,16 +2045,6 @@ static int pool_ctr(struct dm_target *ti, unsigned argc, char **argv)
|
|||
goto out;
|
||||
}
|
||||
|
||||
/*
|
||||
* Set default pool features.
|
||||
*/
|
||||
pool_features_init(&pf);
|
||||
|
||||
dm_consume_args(&as, 4);
|
||||
r = parse_pool_features(&as, &pf, ti);
|
||||
if (r)
|
||||
goto out;
|
||||
|
||||
pt = kzalloc(sizeof(*pt), GFP_KERNEL);
|
||||
if (!pt) {
|
||||
r = -ENOMEM;
|
||||
|
|
@ -2040,6 +2096,13 @@ static int pool_ctr(struct dm_target *ti, unsigned argc, char **argv)
|
|||
}
|
||||
ti->private = pt;
|
||||
|
||||
r = dm_pool_register_metadata_threshold(pt->pool->pmd,
|
||||
calc_metadata_threshold(pt),
|
||||
metadata_low_callback,
|
||||
pool);
|
||||
if (r)
|
||||
goto out_free_pt;
|
||||
|
||||
pt->callbacks.congested_fn = pool_is_congested;
|
||||
dm_table_add_target_callbacks(ti->table, &pt->callbacks);
|
||||
|
||||
|
|
@ -2079,6 +2142,78 @@ static int pool_map(struct dm_target *ti, struct bio *bio)
|
|||
return r;
|
||||
}
|
||||
|
||||
static int maybe_resize_data_dev(struct dm_target *ti, bool *need_commit)
|
||||
{
|
||||
int r;
|
||||
struct pool_c *pt = ti->private;
|
||||
struct pool *pool = pt->pool;
|
||||
sector_t data_size = ti->len;
|
||||
dm_block_t sb_data_size;
|
||||
|
||||
*need_commit = false;
|
||||
|
||||
(void) sector_div(data_size, pool->sectors_per_block);
|
||||
|
||||
r = dm_pool_get_data_dev_size(pool->pmd, &sb_data_size);
|
||||
if (r) {
|
||||
DMERR("failed to retrieve data device size");
|
||||
return r;
|
||||
}
|
||||
|
||||
if (data_size < sb_data_size) {
|
||||
DMERR("pool target (%llu blocks) too small: expected %llu",
|
||||
(unsigned long long)data_size, sb_data_size);
|
||||
return -EINVAL;
|
||||
|
||||
} else if (data_size > sb_data_size) {
|
||||
r = dm_pool_resize_data_dev(pool->pmd, data_size);
|
||||
if (r) {
|
||||
DMERR("failed to resize data device");
|
||||
set_pool_mode(pool, PM_READ_ONLY);
|
||||
return r;
|
||||
}
|
||||
|
||||
*need_commit = true;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int maybe_resize_metadata_dev(struct dm_target *ti, bool *need_commit)
|
||||
{
|
||||
int r;
|
||||
struct pool_c *pt = ti->private;
|
||||
struct pool *pool = pt->pool;
|
||||
dm_block_t metadata_dev_size, sb_metadata_dev_size;
|
||||
|
||||
*need_commit = false;
|
||||
|
||||
metadata_dev_size = get_metadata_dev_size(pool->md_dev);
|
||||
|
||||
r = dm_pool_get_metadata_dev_size(pool->pmd, &sb_metadata_dev_size);
|
||||
if (r) {
|
||||
DMERR("failed to retrieve data device size");
|
||||
return r;
|
||||
}
|
||||
|
||||
if (metadata_dev_size < sb_metadata_dev_size) {
|
||||
DMERR("metadata device (%llu sectors) too small: expected %llu",
|
||||
metadata_dev_size, sb_metadata_dev_size);
|
||||
return -EINVAL;
|
||||
|
||||
} else if (metadata_dev_size > sb_metadata_dev_size) {
|
||||
r = dm_pool_resize_metadata_dev(pool->pmd, metadata_dev_size);
|
||||
if (r) {
|
||||
DMERR("failed to resize metadata device");
|
||||
return r;
|
||||
}
|
||||
|
||||
*need_commit = true;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Retrieves the number of blocks of the data device from
|
||||
* the superblock and compares it to the actual device size,
|
||||
|
|
@ -2093,10 +2228,9 @@ static int pool_map(struct dm_target *ti, struct bio *bio)
|
|||
static int pool_preresume(struct dm_target *ti)
|
||||
{
|
||||
int r;
|
||||
bool need_commit1, need_commit2;
|
||||
struct pool_c *pt = ti->private;
|
||||
struct pool *pool = pt->pool;
|
||||
sector_t data_size = ti->len;
|
||||
dm_block_t sb_data_size;
|
||||
|
||||
/*
|
||||
* Take control of the pool object.
|
||||
|
|
@ -2105,30 +2239,16 @@ static int pool_preresume(struct dm_target *ti)
|
|||
if (r)
|
||||
return r;
|
||||
|
||||
(void) sector_div(data_size, pool->sectors_per_block);
|
||||
|
||||
r = dm_pool_get_data_dev_size(pool->pmd, &sb_data_size);
|
||||
if (r) {
|
||||
DMERR("failed to retrieve data device size");
|
||||
r = maybe_resize_data_dev(ti, &need_commit1);
|
||||
if (r)
|
||||
return r;
|
||||
}
|
||||
|
||||
if (data_size < sb_data_size) {
|
||||
DMERR("pool target too small, is %llu blocks (expected %llu)",
|
||||
(unsigned long long)data_size, sb_data_size);
|
||||
return -EINVAL;
|
||||
|
||||
} else if (data_size > sb_data_size) {
|
||||
r = dm_pool_resize_data_dev(pool->pmd, data_size);
|
||||
if (r) {
|
||||
DMERR("failed to resize data device");
|
||||
/* FIXME Stricter than necessary: Rollback transaction instead here */
|
||||
set_pool_mode(pool, PM_READ_ONLY);
|
||||
return r;
|
||||
}
|
||||
r = maybe_resize_metadata_dev(ti, &need_commit2);
|
||||
if (r)
|
||||
return r;
|
||||
|
||||
if (need_commit1 || need_commit2)
|
||||
(void) commit_or_fallback(pool);
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
|
@ -2549,7 +2669,7 @@ static struct target_type pool_target = {
|
|||
.name = "thin-pool",
|
||||
.features = DM_TARGET_SINGLETON | DM_TARGET_ALWAYS_WRITEABLE |
|
||||
DM_TARGET_IMMUTABLE,
|
||||
.version = {1, 7, 0},
|
||||
.version = {1, 8, 0},
|
||||
.module = THIS_MODULE,
|
||||
.ctr = pool_ctr,
|
||||
.dtr = pool_dtr,
|
||||
|
|
|
|||
|
|
@ -248,7 +248,8 @@ static struct dm_space_map ops = {
|
|||
.new_block = sm_disk_new_block,
|
||||
.commit = sm_disk_commit,
|
||||
.root_size = sm_disk_root_size,
|
||||
.copy_root = sm_disk_copy_root
|
||||
.copy_root = sm_disk_copy_root,
|
||||
.register_threshold_callback = NULL
|
||||
};
|
||||
|
||||
struct dm_space_map *dm_sm_disk_create(struct dm_transaction_manager *tm,
|
||||
|
|
|
|||
|
|
@ -16,6 +16,55 @@
|
|||
|
||||
/*----------------------------------------------------------------*/
|
||||
|
||||
/*
|
||||
* An edge triggered threshold.
|
||||
*/
|
||||
struct threshold {
|
||||
bool threshold_set;
|
||||
bool value_set;
|
||||
dm_block_t threshold;
|
||||
dm_block_t current_value;
|
||||
dm_sm_threshold_fn fn;
|
||||
void *context;
|
||||
};
|
||||
|
||||
static void threshold_init(struct threshold *t)
|
||||
{
|
||||
t->threshold_set = false;
|
||||
t->value_set = false;
|
||||
}
|
||||
|
||||
static void set_threshold(struct threshold *t, dm_block_t value,
|
||||
dm_sm_threshold_fn fn, void *context)
|
||||
{
|
||||
t->threshold_set = true;
|
||||
t->threshold = value;
|
||||
t->fn = fn;
|
||||
t->context = context;
|
||||
}
|
||||
|
||||
static bool below_threshold(struct threshold *t, dm_block_t value)
|
||||
{
|
||||
return t->threshold_set && value <= t->threshold;
|
||||
}
|
||||
|
||||
static bool threshold_already_triggered(struct threshold *t)
|
||||
{
|
||||
return t->value_set && below_threshold(t, t->current_value);
|
||||
}
|
||||
|
||||
static void check_threshold(struct threshold *t, dm_block_t value)
|
||||
{
|
||||
if (below_threshold(t, value) &&
|
||||
!threshold_already_triggered(t))
|
||||
t->fn(t->context);
|
||||
|
||||
t->value_set = true;
|
||||
t->current_value = value;
|
||||
}
|
||||
|
||||
/*----------------------------------------------------------------*/
|
||||
|
||||
/*
|
||||
* Space map interface.
|
||||
*
|
||||
|
|
@ -54,6 +103,8 @@ struct sm_metadata {
|
|||
unsigned allocated_this_transaction;
|
||||
unsigned nr_uncommitted;
|
||||
struct block_op uncommitted[MAX_RECURSIVE_ALLOCATIONS];
|
||||
|
||||
struct threshold threshold;
|
||||
};
|
||||
|
||||
static int add_bop(struct sm_metadata *smm, enum block_op_type type, dm_block_t b)
|
||||
|
|
@ -144,12 +195,6 @@ static void sm_metadata_destroy(struct dm_space_map *sm)
|
|||
kfree(smm);
|
||||
}
|
||||
|
||||
static int sm_metadata_extend(struct dm_space_map *sm, dm_block_t extra_blocks)
|
||||
{
|
||||
DMERR("doesn't support extend");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
static int sm_metadata_get_nr_blocks(struct dm_space_map *sm, dm_block_t *count)
|
||||
{
|
||||
struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm);
|
||||
|
|
@ -335,9 +380,19 @@ static int sm_metadata_new_block_(struct dm_space_map *sm, dm_block_t *b)
|
|||
|
||||
static int sm_metadata_new_block(struct dm_space_map *sm, dm_block_t *b)
|
||||
{
|
||||
dm_block_t count;
|
||||
struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm);
|
||||
|
||||
int r = sm_metadata_new_block_(sm, b);
|
||||
if (r)
|
||||
DMERR("unable to allocate new metadata block");
|
||||
|
||||
r = sm_metadata_get_nr_free(sm, &count);
|
||||
if (r)
|
||||
DMERR("couldn't get free block count");
|
||||
|
||||
check_threshold(&smm->threshold, count);
|
||||
|
||||
return r;
|
||||
}
|
||||
|
||||
|
|
@ -357,6 +412,18 @@ static int sm_metadata_commit(struct dm_space_map *sm)
|
|||
return 0;
|
||||
}
|
||||
|
||||
static int sm_metadata_register_threshold_callback(struct dm_space_map *sm,
|
||||
dm_block_t threshold,
|
||||
dm_sm_threshold_fn fn,
|
||||
void *context)
|
||||
{
|
||||
struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm);
|
||||
|
||||
set_threshold(&smm->threshold, threshold, fn, context);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int sm_metadata_root_size(struct dm_space_map *sm, size_t *result)
|
||||
{
|
||||
*result = sizeof(struct disk_sm_root);
|
||||
|
|
@ -382,6 +449,8 @@ static int sm_metadata_copy_root(struct dm_space_map *sm, void *where_le, size_t
|
|||
return 0;
|
||||
}
|
||||
|
||||
static int sm_metadata_extend(struct dm_space_map *sm, dm_block_t extra_blocks);
|
||||
|
||||
static struct dm_space_map ops = {
|
||||
.destroy = sm_metadata_destroy,
|
||||
.extend = sm_metadata_extend,
|
||||
|
|
@ -395,7 +464,8 @@ static struct dm_space_map ops = {
|
|||
.new_block = sm_metadata_new_block,
|
||||
.commit = sm_metadata_commit,
|
||||
.root_size = sm_metadata_root_size,
|
||||
.copy_root = sm_metadata_copy_root
|
||||
.copy_root = sm_metadata_copy_root,
|
||||
.register_threshold_callback = sm_metadata_register_threshold_callback
|
||||
};
|
||||
|
||||
/*----------------------------------------------------------------*/
|
||||
|
|
@ -410,7 +480,7 @@ static void sm_bootstrap_destroy(struct dm_space_map *sm)
|
|||
|
||||
static int sm_bootstrap_extend(struct dm_space_map *sm, dm_block_t extra_blocks)
|
||||
{
|
||||
DMERR("boostrap doesn't support extend");
|
||||
DMERR("bootstrap doesn't support extend");
|
||||
|
||||
return -EINVAL;
|
||||
}
|
||||
|
|
@ -450,7 +520,7 @@ static int sm_bootstrap_count_is_more_than_one(struct dm_space_map *sm,
|
|||
static int sm_bootstrap_set_count(struct dm_space_map *sm, dm_block_t b,
|
||||
uint32_t count)
|
||||
{
|
||||
DMERR("boostrap doesn't support set_count");
|
||||
DMERR("bootstrap doesn't support set_count");
|
||||
|
||||
return -EINVAL;
|
||||
}
|
||||
|
|
@ -491,7 +561,7 @@ static int sm_bootstrap_commit(struct dm_space_map *sm)
|
|||
|
||||
static int sm_bootstrap_root_size(struct dm_space_map *sm, size_t *result)
|
||||
{
|
||||
DMERR("boostrap doesn't support root_size");
|
||||
DMERR("bootstrap doesn't support root_size");
|
||||
|
||||
return -EINVAL;
|
||||
}
|
||||
|
|
@ -499,7 +569,7 @@ static int sm_bootstrap_root_size(struct dm_space_map *sm, size_t *result)
|
|||
static int sm_bootstrap_copy_root(struct dm_space_map *sm, void *where,
|
||||
size_t max)
|
||||
{
|
||||
DMERR("boostrap doesn't support copy_root");
|
||||
DMERR("bootstrap doesn't support copy_root");
|
||||
|
||||
return -EINVAL;
|
||||
}
|
||||
|
|
@ -517,11 +587,42 @@ static struct dm_space_map bootstrap_ops = {
|
|||
.new_block = sm_bootstrap_new_block,
|
||||
.commit = sm_bootstrap_commit,
|
||||
.root_size = sm_bootstrap_root_size,
|
||||
.copy_root = sm_bootstrap_copy_root
|
||||
.copy_root = sm_bootstrap_copy_root,
|
||||
.register_threshold_callback = NULL
|
||||
};
|
||||
|
||||
/*----------------------------------------------------------------*/
|
||||
|
||||
static int sm_metadata_extend(struct dm_space_map *sm, dm_block_t extra_blocks)
|
||||
{
|
||||
int r, i;
|
||||
enum allocation_event ev;
|
||||
struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm);
|
||||
dm_block_t old_len = smm->ll.nr_blocks;
|
||||
|
||||
/*
|
||||
* Flick into a mode where all blocks get allocated in the new area.
|
||||
*/
|
||||
smm->begin = old_len;
|
||||
memcpy(&smm->sm, &bootstrap_ops, sizeof(smm->sm));
|
||||
|
||||
/*
|
||||
* Extend.
|
||||
*/
|
||||
r = sm_ll_extend(&smm->ll, extra_blocks);
|
||||
|
||||
/*
|
||||
* Switch back to normal behaviour.
|
||||
*/
|
||||
memcpy(&smm->sm, &ops, sizeof(smm->sm));
|
||||
for (i = old_len; !r && i < smm->begin; i++)
|
||||
r = sm_ll_inc(&smm->ll, i, &ev);
|
||||
|
||||
return r;
|
||||
}
|
||||
|
||||
/*----------------------------------------------------------------*/
|
||||
|
||||
struct dm_space_map *dm_sm_metadata_init(void)
|
||||
{
|
||||
struct sm_metadata *smm;
|
||||
|
|
@ -549,6 +650,7 @@ int dm_sm_metadata_create(struct dm_space_map *sm,
|
|||
smm->recursion_count = 0;
|
||||
smm->allocated_this_transaction = 0;
|
||||
smm->nr_uncommitted = 0;
|
||||
threshold_init(&smm->threshold);
|
||||
|
||||
memcpy(&smm->sm, &bootstrap_ops, sizeof(smm->sm));
|
||||
|
||||
|
|
@ -590,6 +692,7 @@ int dm_sm_metadata_open(struct dm_space_map *sm,
|
|||
smm->recursion_count = 0;
|
||||
smm->allocated_this_transaction = 0;
|
||||
smm->nr_uncommitted = 0;
|
||||
threshold_init(&smm->threshold);
|
||||
|
||||
memcpy(&smm->old_ll, &smm->ll, sizeof(smm->old_ll));
|
||||
return 0;
|
||||
|
|
|
|||
|
|
@ -9,6 +9,8 @@
|
|||
|
||||
#include "dm-block-manager.h"
|
||||
|
||||
typedef void (*dm_sm_threshold_fn)(void *context);
|
||||
|
||||
/*
|
||||
* struct dm_space_map keeps a record of how many times each block in a device
|
||||
* is referenced. It needs to be fixed on disk as part of the transaction.
|
||||
|
|
@ -59,6 +61,15 @@ struct dm_space_map {
|
|||
*/
|
||||
int (*root_size)(struct dm_space_map *sm, size_t *result);
|
||||
int (*copy_root)(struct dm_space_map *sm, void *copy_to_here_le, size_t len);
|
||||
|
||||
/*
|
||||
* You can register one threshold callback which is edge-triggered
|
||||
* when the free space in the space map drops below the threshold.
|
||||
*/
|
||||
int (*register_threshold_callback)(struct dm_space_map *sm,
|
||||
dm_block_t threshold,
|
||||
dm_sm_threshold_fn fn,
|
||||
void *context);
|
||||
};
|
||||
|
||||
/*----------------------------------------------------------------*/
|
||||
|
|
@ -131,4 +142,16 @@ static inline int dm_sm_copy_root(struct dm_space_map *sm, void *copy_to_here_le
|
|||
return sm->copy_root(sm, copy_to_here_le, len);
|
||||
}
|
||||
|
||||
static inline int dm_sm_register_threshold_callback(struct dm_space_map *sm,
|
||||
dm_block_t threshold,
|
||||
dm_sm_threshold_fn fn,
|
||||
void *context)
|
||||
{
|
||||
if (sm->register_threshold_callback)
|
||||
return sm->register_threshold_callback(sm, threshold, fn, context);
|
||||
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
|
||||
#endif /* _LINUX_DM_SPACE_MAP_H */
|
||||
|
|
|
|||
|
|
@ -79,11 +79,26 @@ typedef int (*dm_ioctl_fn) (struct dm_target *ti, unsigned int cmd,
|
|||
typedef int (*dm_merge_fn) (struct dm_target *ti, struct bvec_merge_data *bvm,
|
||||
struct bio_vec *biovec, int max_size);
|
||||
|
||||
/*
|
||||
* These iteration functions are typically used to check (and combine)
|
||||
* properties of underlying devices.
|
||||
* E.g. Does at least one underlying device support flush?
|
||||
* Does any underlying device not support WRITE_SAME?
|
||||
*
|
||||
* The callout function is called once for each contiguous section of
|
||||
* an underlying device. State can be maintained in *data.
|
||||
* Return non-zero to stop iterating through any further devices.
|
||||
*/
|
||||
typedef int (*iterate_devices_callout_fn) (struct dm_target *ti,
|
||||
struct dm_dev *dev,
|
||||
sector_t start, sector_t len,
|
||||
void *data);
|
||||
|
||||
/*
|
||||
* This function must iterate through each section of device used by the
|
||||
* target until it encounters a non-zero return code, which it then returns.
|
||||
* Returns zero if no callout returned non-zero.
|
||||
*/
|
||||
typedef int (*dm_iterate_devices_fn) (struct dm_target *ti,
|
||||
iterate_devices_callout_fn fn,
|
||||
void *data);
|
||||
|
|
|
|||
Loading…
Reference in a new issue