Commit e93dd910 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'dm-3.12-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm 

Pull device-mapper fixes from Mike Snitzer:
 "A few fixes for dm-snapshot, a 32 bit fix for dm-stats, a couple error
  handling fixes for dm-multipath.  A fix for the thin provisioning
  target to not expose non-zero discard limits if discards are disabled.

  Lastly, add two DM module parameters which allow users to tune the
  emergency memory reserves that DM mainatins per device -- this helps
  fix a long-standing issue for dm-multipath.  The conservative default
  reserve for request-based dm-multipath devices (256) has proven
  problematic for users with many multipathed SCSI devices but
  relatively little memory.  To responsibly select a smaller value users
  should use the new nr_bios tracepoint info (via commit 75afb352
  "block: Add nr_bios to block_rq_remap tracepoint") to determine the
  peak number of bios their workloads create"

* tag 'dm-3.12-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm: add reserved_bio_based_ios module parameter
  dm: add reserved_rq_based_ios module parameter
  dm: lower bio-based mempool reservation
  dm thin: do not expose non-zero discard limits if discards disabled
  dm mpath: disable WRITE SAME if it fails
  dm-snapshot: fix performance degradation due to small hash size
  dm snapshot: workaround for a false positive lockdep warning
  dm stats: fix possible counter corruption on 32-bit systems
  dm mpath: do not fail path on -ENOSPC
parents b4820416 e8603136

drivers/md/dm-io.c

+3 −4
Original line number Diff line number Diff line
@@ -19,8 +19,6 @@ 
#define DM_MSG_PREFIX "io"



#define DM_IO_MAX_REGIONS	BITS_PER_LONG

#define MIN_IOS		16

#define MIN_BIOS	16



struct dm_io_client {

	mempool_t *pool;
@@ -50,16 +48,17 @@ static struct kmem_cache *_dm_io_cache; 
struct dm_io_client *dm_io_client_create(void)

{

	struct dm_io_client *client;

	unsigned min_ios = dm_get_reserved_bio_based_ios();



	client = kmalloc(sizeof(*client), GFP_KERNEL);

	if (!client)

		return ERR_PTR(-ENOMEM);



	client->pool = mempool_create_slab_pool(MIN_IOS, _dm_io_cache);

	client->pool = mempool_create_slab_pool(min_ios, _dm_io_cache);

	if (!client->pool)

		goto bad;



	client->bios = bioset_create(MIN_BIOS, 0);

	client->bios = bioset_create(min_ios, 0);

	if (!client->bios)

		goto bad;

drivers/md/dm-mpath.c

+14 −4
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ 


#include <linux/device-mapper.h>



#include "dm.h"

#include "dm-path-selector.h"

#include "dm-uevent.h"
@@ -116,8 +117,6 @@ struct dm_mpath_io { 


typedef int (*action_fn) (struct pgpath *pgpath);



#define MIN_IOS 256	/* Mempool size */



static struct kmem_cache *_mpio_cache;



static struct workqueue_struct *kmultipathd, *kmpath_handlerd;
@@ -190,6 +189,7 @@ static void free_priority_group(struct priority_group *pg, 
static struct multipath *alloc_multipath(struct dm_target *ti)

{

	struct multipath *m;

	unsigned min_ios = dm_get_reserved_rq_based_ios();



	m = kzalloc(sizeof(*m), GFP_KERNEL);

	if (m) {
@@ -202,7 +202,7 @@ static struct multipath *alloc_multipath(struct dm_target *ti) 
		INIT_WORK(&m->trigger_event, trigger_event);

		init_waitqueue_head(&m->pg_init_wait);

		mutex_init(&m->work_mutex);

		m->mpio_pool = mempool_create_slab_pool(MIN_IOS, _mpio_cache);

		m->mpio_pool = mempool_create_slab_pool(min_ios, _mpio_cache);

		if (!m->mpio_pool) {

			kfree(m);

			return NULL;
@@ -1268,6 +1268,7 @@ static int noretry_error(int error) 
	case -EREMOTEIO:

	case -EILSEQ:

	case -ENODATA:

	case -ENOSPC:

		return 1;

	}
@@ -1298,8 +1299,17 @@ static int do_end_io(struct multipath *m, struct request *clone, 
	if (!error && !clone->errors)

		return 0;	/* I/O complete */



	if (noretry_error(error))

	if (noretry_error(error)) {

		if ((clone->cmd_flags & REQ_WRITE_SAME) &&

		    !clone->q->limits.max_write_same_sectors) {

			struct queue_limits *limits;



			/* device doesn't really support WRITE SAME, disable it */

			limits = dm_get_queue_limits(dm_table_get_md(m->ti->table));

			limits->max_write_same_sectors = 0;

		}

		return error;

	}



	if (mpio->pgpath)

		fail_path(mpio->pgpath);

drivers/md/dm-snap-persistent.c

+1 −1
Original line number Diff line number Diff line
@@ -256,7 +256,7 @@ static int chunk_io(struct pstore *ps, void *area, chunk_t chunk, int rw, 
	 */

	INIT_WORK_ONSTACK(&req.work, do_metadata);

	queue_work(ps->metadata_wq, &req.work);

	flush_work(&req.work);

	flush_workqueue(ps->metadata_wq);



	return req.result;

}

drivers/md/dm-snap.c

+2 −3
Original line number Diff line number Diff line
@@ -725,17 +725,16 @@ static int calc_max_buckets(void) 
 */

static int init_hash_tables(struct dm_snapshot *s)

{

	sector_t hash_size, cow_dev_size, origin_dev_size, max_buckets;

	sector_t hash_size, cow_dev_size, max_buckets;



	/*

	 * Calculate based on the size of the original volume or

	 * the COW volume...

	 */

	cow_dev_size = get_dev_size(s->cow->bdev);

	origin_dev_size = get_dev_size(s->origin->bdev);

	max_buckets = calc_max_buckets();



	hash_size = min(origin_dev_size, cow_dev_size) >> s->store->chunk_shift;

	hash_size = cow_dev_size >> s->store->chunk_shift;

	hash_size = min(hash_size, max_buckets);



	if (hash_size < 64)

drivers/md/dm-stats.c

+17 −6
Original line number Diff line number Diff line
@@ -451,19 +451,26 @@ static void dm_stat_for_entry(struct dm_stat *s, size_t entry, 
	struct dm_stat_percpu *p;



	/*

	 * For strict correctness we should use local_irq_disable/enable

	 * For strict correctness we should use local_irq_save/restore

	 * instead of preempt_disable/enable.

	 *

	 * This is racy if the driver finishes bios from non-interrupt

	 * context as well as from interrupt context or from more different

	 * interrupts.

	 * preempt_disable/enable is racy if the driver finishes bios

	 * from non-interrupt context as well as from interrupt context

	 * or from more different interrupts.

	 *

	 * However, the race only results in not counting some events,

	 * so it is acceptable.

	 * On 64-bit architectures the race only results in not counting some

	 * events, so it is acceptable.  On 32-bit architectures the race could

	 * cause the counter going off by 2^32, so we need to do proper locking

	 * there.

	 *

	 * part_stat_lock()/part_stat_unlock() have this race too.

	 */

#if BITS_PER_LONG == 32

	unsigned long flags;

	local_irq_save(flags);

#else

	preempt_disable();

#endif

	p = &s->stat_percpu[smp_processor_id()][entry];



	if (!end) {
@@ -478,7 +485,11 @@ static void dm_stat_for_entry(struct dm_stat *s, size_t entry, 
		p->ticks[idx] += duration;

	}



#if BITS_PER_LONG == 32

	local_irq_restore(flags);

#else

	preempt_enable();

#endif

}



static void __dm_stat_bio(struct dm_stat *s, unsigned long bi_rw,

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