Merge tag 'dm-3.15-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:
 "A dm-crypt fix for a cpu hotplug crash that switches from using
  per-cpu data to a mempool allocation (which offers allocation with cpu
  locality, and there is no inter-cpu communication on slab allocation).

  A couple dm-thinp stable fixes to address "out-of-data-space" issues.

  A dm-multipath fix for a LOCKDEP warning introduced in 3.15-rc1"

* tag 'dm-3.15-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm mpath: fix lock order inconsistency in multipath_ioctl
  dm thin: add timeout to stop out-of-data-space mode holding IO forever
  dm thin: allow metadata commit if pool is in PM_OUT_OF_DATA_SPACE mode
  dm crypt: fix cpu hotplug crash by removing per-cpu structure

3 files changed, 35 insertions, 51 deletions

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 784695d22fde..53b213226c01 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -19,7 +19,6 @@
 #include <linux/crypto.h>
 #include <linux/workqueue.h>
 #include <linux/backing-dev.h>
-#include <linux/percpu.h>
 #include <linux/atomic.h>
 #include <linux/scatterlist.h>
 #include <asm/page.h>
@@ -43,6 +42,7 @@ struct convert_context {
         struct bvec_iter iter_out;
         sector_t cc_sector;
         atomic_t cc_pending;
+        struct ablkcipher_request *req;
 };
 
 /*
@@ -111,15 +111,7 @@ struct iv_tcw_private {
 enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID };
 
 /*
- * Duplicated per-CPU state for cipher.
- */
-struct crypt_cpu {
-        struct ablkcipher_request *req;
-};
-
-/*
- * The fields in here must be read only after initialization,
- * changing state should be in crypt_cpu.
+ * The fields in here must be read only after initialization.
  */
 struct crypt_config {
         struct dm_dev *dev;
@@ -150,12 +142,6 @@ struct crypt_config {
         sector_t iv_offset;
         unsigned int iv_size;
 
-        /*
-         * Duplicated per cpu state. Access through
-         * per_cpu_ptr() only.
-         */
-        struct crypt_cpu __percpu *cpu;
-
         /* ESSIV: struct crypto_cipher *essiv_tfm */
         void *iv_private;
         struct crypto_ablkcipher **tfms;
@@ -192,11 +178,6 @@ static void clone_init(struct dm_crypt_io *, struct bio *);
 static void kcryptd_queue_crypt(struct dm_crypt_io *io);
 static u8 *iv_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq);
 
-static struct crypt_cpu *this_crypt_config(struct crypt_config *cc)
-{
-        return this_cpu_ptr(cc->cpu);
-}
-
 /*
  * Use this to access cipher attributes that are the same for each CPU.
  */
@@ -903,16 +884,15 @@ static void kcryptd_async_done(struct crypto_async_request *async_req,
 static void crypt_alloc_req(struct crypt_config *cc,
                             struct convert_context *ctx)
 {
-        struct crypt_cpu *this_cc = this_crypt_config(cc);
         unsigned key_index = ctx->cc_sector & (cc->tfms_count - 1);
 
-        if (!this_cc->req)
-                this_cc->req = mempool_alloc(cc->req_pool, GFP_NOIO);
+        if (!ctx->req)
+                ctx->req = mempool_alloc(cc->req_pool, GFP_NOIO);
 
-        ablkcipher_request_set_tfm(this_cc->req, cc->tfms[key_index]);
-        ablkcipher_request_set_callback(this_cc->req,
+        ablkcipher_request_set_tfm(ctx->req, cc->tfms[key_index]);
+        ablkcipher_request_set_callback(ctx->req,
             CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
-            kcryptd_async_done, dmreq_of_req(cc, this_cc->req));
+            kcryptd_async_done, dmreq_of_req(cc, ctx->req));
 }
 
 /*
@@ -921,7 +901,6 @@ static void crypt_alloc_req(struct crypt_config *cc,
 static int crypt_convert(struct crypt_config *cc,
                          struct convert_context *ctx)
 {
-        struct crypt_cpu *this_cc = this_crypt_config(cc);
         int r;
 
         atomic_set(&ctx->cc_pending, 1);
@@ -932,7 +911,7 @@ static int crypt_convert(struct crypt_config *cc,
 
                 atomic_inc(&ctx->cc_pending);
 
-                r = crypt_convert_block(cc, ctx, this_cc->req);
+                r = crypt_convert_block(cc, ctx, ctx->req);
 
                 switch (r) {
                 /* async */
@@ -941,7 +920,7 @@ static int crypt_convert(struct crypt_config *cc,
                         reinit_completion(&ctx->restart);
                         /* fall through*/
                 case -EINPROGRESS:
-                        this_cc->req = NULL;
+                        ctx->req = NULL;
                         ctx->cc_sector++;
                         continue;
 
@@ -1040,6 +1019,7 @@ static struct dm_crypt_io *crypt_io_alloc(struct crypt_config *cc,
         io->sector = sector;
         io->error = 0;
         io->base_io = NULL;
+        io->ctx.req = NULL;
         atomic_set(&io->io_pending, 0);
 
         return io;
@@ -1065,6 +1045,8 @@ static void crypt_dec_pending(struct dm_crypt_io *io)
         if (!atomic_dec_and_test(&io->io_pending))
                 return;
 
+        if (io->ctx.req)
+                mempool_free(io->ctx.req, cc->req_pool);
         mempool_free(io, cc->io_pool);
 
         if (likely(!base_io))
@@ -1492,8 +1474,6 @@ static int crypt_wipe_key(struct crypt_config *cc)
 static void crypt_dtr(struct dm_target *ti)
 {
         struct crypt_config *cc = ti->private;
-        struct crypt_cpu *cpu_cc;
-        int cpu;
 
         ti->private = NULL;
 
@@ -1505,13 +1485,6 @@ static void crypt_dtr(struct dm_target *ti)
         if (cc->crypt_queue)
                 destroy_workqueue(cc->crypt_queue);
 
-        if (cc->cpu)
-                for_each_possible_cpu(cpu) {
-                        cpu_cc = per_cpu_ptr(cc->cpu, cpu);
-                        if (cpu_cc->req)
-                                mempool_free(cpu_cc->req, cc->req_pool);
-                }
-
         crypt_free_tfms(cc);
 
         if (cc->bs)
@@ -1530,9 +1503,6 @@ static void crypt_dtr(struct dm_target *ti)
         if (cc->dev)
                 dm_put_device(ti, cc->dev);
 
-        if (cc->cpu)
-                free_percpu(cc->cpu);
-
         kzfree(cc->cipher);
         kzfree(cc->cipher_string);
 
@@ -1588,13 +1558,6 @@ static int crypt_ctr_cipher(struct dm_target *ti,
         if (tmp)
                 DMWARN("Ignoring unexpected additional cipher options");
 
-        cc->cpu = __alloc_percpu(sizeof(*(cc->cpu)),
-                                 __alignof__(struct crypt_cpu));
-        if (!cc->cpu) {
-                ti->error = "Cannot allocate per cpu state";
-                goto bad_mem;
-        }
-
         /*
          * For compatibility with the original dm-crypt mapping format, if
          * only the cipher name is supplied, use cbc-plain.
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index aa009e865871..fa0f6cbd6a41 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -1566,8 +1566,8 @@ static int multipath_ioctl(struct dm_target *ti, unsigned int cmd,
                 }
                 if (m->pg_init_required)
                         __pg_init_all_paths(m);
-                spin_unlock_irqrestore(&m->lock, flags);
                 dm_table_run_md_queue_async(m->ti->table);
+                spin_unlock_irqrestore(&m->lock, flags);
         }
 
         return r ? : __blkdev_driver_ioctl(bdev, mode, cmd, arg);
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 13abade76ad9..2e71de8e0048 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -27,6 +27,7 @@
 #define MAPPING_POOL_SIZE 1024
 #define PRISON_CELLS 1024
 #define COMMIT_PERIOD HZ
+#define NO_SPACE_TIMEOUT (HZ * 60)
 
 DECLARE_DM_KCOPYD_THROTTLE_WITH_MODULE_PARM(snapshot_copy_throttle,
                 "A percentage of time allocated for copy on write");
@@ -175,6 +176,7 @@ struct pool {
         struct workqueue_struct *wq;
         struct work_struct worker;
         struct delayed_work waker;
+        struct delayed_work no_space_timeout;
 
         unsigned long last_commit_jiffies;
         unsigned ref_count;
@@ -935,7 +937,7 @@ static int commit(struct pool *pool)
 {
         int r;
 
-        if (get_pool_mode(pool) != PM_WRITE)
+        if (get_pool_mode(pool) >= PM_READ_ONLY)
                 return -EINVAL;
 
         r = dm_pool_commit_metadata(pool->pmd);
@@ -1590,6 +1592,20 @@ static void do_waker(struct work_struct *ws)
         queue_delayed_work(pool->wq, &pool->waker, COMMIT_PERIOD);
 }
 
+/*
+ * We're holding onto IO to allow userland time to react.  After the
+ * timeout either the pool will have been resized (and thus back in
+ * PM_WRITE mode), or we degrade to PM_READ_ONLY and start erroring IO.
+ */
+static void do_no_space_timeout(struct work_struct *ws)
+{
+        struct pool *pool = container_of(to_delayed_work(ws), struct pool,
+                                         no_space_timeout);
+
+        if (get_pool_mode(pool) == PM_OUT_OF_DATA_SPACE && !pool->pf.error_if_no_space)
+                set_pool_mode(pool, PM_READ_ONLY);
+}
+
 /*----------------------------------------------------------------*/
 
 struct noflush_work {
@@ -1715,6 +1731,9 @@ static void set_pool_mode(struct pool *pool, enum pool_mode new_mode)
                 pool->process_discard = process_discard;
                 pool->process_prepared_mapping = process_prepared_mapping;
                 pool->process_prepared_discard = process_prepared_discard_passdown;
+
+                if (!pool->pf.error_if_no_space)
+                        queue_delayed_work(pool->wq, &pool->no_space_timeout, NO_SPACE_TIMEOUT);
                 break;
 
         case PM_WRITE:
@@ -2100,6 +2119,7 @@ static struct pool *pool_create(struct mapped_device *pool_md,
 
         INIT_WORK(&pool->worker, do_worker);
         INIT_DELAYED_WORK(&pool->waker, do_waker);
+        INIT_DELAYED_WORK(&pool->no_space_timeout, do_no_space_timeout);
         spin_lock_init(&pool->lock);
         bio_list_init(&pool->deferred_flush_bios);
         INIT_LIST_HEAD(&pool->prepared_mappings);
@@ -2662,6 +2682,7 @@ static void pool_postsuspend(struct dm_target *ti)
         struct pool *pool = pt->pool;
 
         cancel_delayed_work(&pool->waker);
+        cancel_delayed_work(&pool->no_space_timeout);
         flush_workqueue(pool->wq);
         (void) commit(pool);
 }