25 files changed, 883 insertions, 172 deletions

diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig
index 34a8c60a254a..9b6fbf044fd8 100644
--- a/drivers/md/Kconfig
+++ b/drivers/md/Kconfig
@@ -267,6 +267,12 @@ config DM_MULTIPATH_RDAC
         ---help---
           Multipath support for LSI/Engenio RDAC.
 
+config DM_MULTIPATH_HP
+        tristate "HP MSA multipath support (EXPERIMENTAL)"
+        depends on DM_MULTIPATH && BLK_DEV_DM && EXPERIMENTAL
+        ---help---
+          Multipath support for HP MSA (Active/Passive) series hardware.
+
 config DM_DELAY
         tristate "I/O delaying target (EXPERIMENTAL)"
         depends on BLK_DEV_DM && EXPERIMENTAL
@@ -276,4 +282,10 @@ config DM_DELAY
 
         If unsure, say N.
 
+config DM_UEVENT
+        bool "DM uevents (EXPERIMENTAL)"
+        depends on BLK_DEV_DM && EXPERIMENTAL
+        ---help---
+        Generate udev events for DM events.
+
 endif # MD
diff --git a/drivers/md/Makefile b/drivers/md/Makefile
index c49366cdc05d..d9aa7edb8780 100644
--- a/drivers/md/Makefile
+++ b/drivers/md/Makefile
@@ -8,6 +8,7 @@ dm-multipath-objs := dm-hw-handler.o dm-path-selector.o dm-mpath.o
 dm-snapshot-objs := dm-snap.o dm-exception-store.o
 dm-mirror-objs  := dm-log.o dm-raid1.o
 dm-rdac-objs    := dm-mpath-rdac.o
+dm-hp-sw-objs   := dm-mpath-hp-sw.o
 md-mod-objs     := md.o bitmap.o
 raid456-objs    := raid5.o raid6algos.o raid6recov.o raid6tables.o \
                    raid6int1.o raid6int2.o raid6int4.o \
@@ -35,6 +36,7 @@ obj-$(CONFIG_DM_CRYPT)		+= dm-crypt.o
 obj-$(CONFIG_DM_DELAY)          += dm-delay.o
 obj-$(CONFIG_DM_MULTIPATH)      += dm-multipath.o dm-round-robin.o
 obj-$(CONFIG_DM_MULTIPATH_EMC)  += dm-emc.o
+obj-$(CONFIG_DM_MULTIPATH_HP)   += dm-hp-sw.o
 obj-$(CONFIG_DM_MULTIPATH_RDAC) += dm-rdac.o
 obj-$(CONFIG_DM_SNAPSHOT)       += dm-snapshot.o
 obj-$(CONFIG_DM_MIRROR)         += dm-mirror.o
@@ -48,6 +50,10 @@ ifeq ($(CONFIG_ALTIVEC),y)
 altivec_flags := -maltivec -mabi=altivec
 endif
 
+ifeq ($(CONFIG_DM_UEVENT),y)
+dm-mod-objs                     += dm-uevent.o
+endif
+
 targets += raid6int1.c
 $(obj)/raid6int1.c:   UNROLL := 1
 $(obj)/raid6int1.c:   $(src)/raid6int.uc $(src)/unroll.pl FORCE
diff --git a/drivers/md/dm-bio-list.h b/drivers/md/dm-bio-list.h
index 3f7b827649e3..d4509be0fe67 100644
--- a/drivers/md/dm-bio-list.h
+++ b/drivers/md/dm-bio-list.h
@@ -21,11 +21,6 @@ static inline int bio_list_empty(const struct bio_list *bl)
         return bl->head == NULL;
 }
 
-#define BIO_LIST_INIT { .head = NULL, .tail = NULL }
-
-#define BIO_LIST(bl) \
-        struct bio_list bl = BIO_LIST_INIT
-
 static inline void bio_list_init(struct bio_list *bl)
 {
         bl->head = bl->tail = NULL;
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 64fee90bb68b..0eb5416798bd 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -36,7 +36,6 @@ struct dm_crypt_io {
         struct work_struct work;
         atomic_t pending;
         int error;
-        int post_process;
 };
 
 /*
@@ -57,7 +56,7 @@ struct crypt_config;
 
 struct crypt_iv_operations {
         int (*ctr)(struct crypt_config *cc, struct dm_target *ti,
-                   const char *opts);
+                   const char *opts);
         void (*dtr)(struct crypt_config *cc);
         const char *(*status)(struct crypt_config *cc);
         int (*generator)(struct crypt_config *cc, u8 *iv, sector_t sector);
@@ -80,6 +79,8 @@ struct crypt_config {
         mempool_t *page_pool;
         struct bio_set *bs;
 
+        struct workqueue_struct *io_queue;
+        struct workqueue_struct *crypt_queue;
         /*
          * crypto related data
          */
@@ -112,7 +113,7 @@ static void clone_init(struct dm_crypt_io *, struct bio *);
  * Different IV generation algorithms:
  *
  * plain: the initial vector is the 32-bit little-endian version of the sector
- *        number, padded with zeros if neccessary.
+ *        number, padded with zeros if necessary.
  *
  * essiv: "encrypted sector|salt initial vector", the sector number is
  *        encrypted with the bulk cipher using a salt as key. The salt
@@ -137,7 +138,7 @@ static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, sector_t sector)
 }
 
 static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
-                              const char *opts)
+                              const char *opts)
 {
         struct crypto_cipher *essiv_tfm;
         struct crypto_hash *hash_tfm;
@@ -175,6 +176,7 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
 
         if (err) {
                 ti->error = "Error calculating hash in ESSIV";
+                kfree(salt);
                 return err;
         }
 
@@ -188,7 +190,7 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
         if (crypto_cipher_blocksize(essiv_tfm) !=
             crypto_blkcipher_ivsize(cc->tfm)) {
                 ti->error = "Block size of ESSIV cipher does "
-                                "not match IV size of block cipher";
+                            "not match IV size of block cipher";
                 crypto_free_cipher(essiv_tfm);
                 kfree(salt);
                 return -EINVAL;
@@ -319,10 +321,10 @@ crypt_convert_scatterlist(struct crypt_config *cc, struct scatterlist *out,
         return r;
 }
 
-static void
-crypt_convert_init(struct crypt_config *cc, struct convert_context *ctx,
-                   struct bio *bio_out, struct bio *bio_in,
-                   sector_t sector, int write)
+static void crypt_convert_init(struct crypt_config *cc,
+                               struct convert_context *ctx,
+                               struct bio *bio_out, struct bio *bio_in,
+                               sector_t sector, int write)
 {
         ctx->bio_in = bio_in;
         ctx->bio_out = bio_out;
@@ -338,7 +340,7 @@ crypt_convert_init(struct crypt_config *cc, struct convert_context *ctx,
  * Encrypt / decrypt data from one bio to another one (can be the same one)
  */
 static int crypt_convert(struct crypt_config *cc,
-                         struct convert_context *ctx)
+                         struct convert_context *ctx)
 {
         int r = 0;
 
@@ -370,7 +372,7 @@ static int crypt_convert(struct crypt_config *cc,
                 }
 
                 r = crypt_convert_scatterlist(cc, &sg_out, &sg_in, sg_in.length,
-                                              ctx->write, ctx->sector);
+                                              ctx->write, ctx->sector);
                 if (r < 0)
                         break;
 
@@ -380,13 +382,13 @@ static int crypt_convert(struct crypt_config *cc,
         return r;
 }
 
- static void dm_crypt_bio_destructor(struct bio *bio)
- {
+static void dm_crypt_bio_destructor(struct bio *bio)
+{
         struct dm_crypt_io *io = bio->bi_private;
         struct crypt_config *cc = io->target->private;
 
         bio_free(bio, cc->bs);
- }
+}
 
 /*
  * Generate a new unfragmented bio with the given size
@@ -458,7 +460,7 @@ static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone)
  * One of the bios was finished. Check for completion of
  * the whole request and correctly clean up the buffer.
  */
-static void dec_pending(struct dm_crypt_io *io, int error)
+static void crypt_dec_pending(struct dm_crypt_io *io, int error)
 {
         struct crypt_config *cc = (struct crypt_config *) io->target->private;
 
@@ -474,18 +476,36 @@ static void dec_pending(struct dm_crypt_io *io, int error)
 }
 
 /*
- * kcryptd:
+ * kcryptd/kcryptd_io:
  *
  * Needed because it would be very unwise to do decryption in an
  * interrupt context.
+ *
+ * kcryptd performs the actual encryption or decryption.
+ *
+ * kcryptd_io performs the IO submission.
+ *
+ * They must be separated as otherwise the final stages could be
+ * starved by new requests which can block in the first stages due
+ * to memory allocation.
  */
-static struct workqueue_struct *_kcryptd_workqueue;
 static void kcryptd_do_work(struct work_struct *work);
+static void kcryptd_do_crypt(struct work_struct *work);
 
 static void kcryptd_queue_io(struct dm_crypt_io *io)
 {
+        struct crypt_config *cc = io->target->private;
+
         INIT_WORK(&io->work, kcryptd_do_work);
-        queue_work(_kcryptd_workqueue, &io->work);
+        queue_work(cc->io_queue, &io->work);
+}
+
+static void kcryptd_queue_crypt(struct dm_crypt_io *io)
+{
+        struct crypt_config *cc = io->target->private;
+
+        INIT_WORK(&io->work, kcryptd_do_crypt);
+        queue_work(cc->crypt_queue, &io->work);
 }
 
 static void crypt_endio(struct bio *clone, int error)
@@ -508,13 +528,12 @@ static void crypt_endio(struct bio *clone, int error)
         }
 
         bio_put(clone);
-        io->post_process = 1;
-        kcryptd_queue_io(io);
+        kcryptd_queue_crypt(io);
         return;
 
 out:
         bio_put(clone);
-        dec_pending(io, error);
+        crypt_dec_pending(io, error);
 }
 
 static void clone_init(struct dm_crypt_io *io, struct bio *clone)
@@ -544,7 +563,7 @@ static void process_read(struct dm_crypt_io *io)
          */
         clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs);
         if (unlikely(!clone)) {
-                dec_pending(io, -ENOMEM);
+                crypt_dec_pending(io, -ENOMEM);
                 return;
         }
 
@@ -579,7 +598,7 @@ static void process_write(struct dm_crypt_io *io)
         while (remaining) {
                 clone = crypt_alloc_buffer(io, remaining);
                 if (unlikely(!clone)) {
-                        dec_pending(io, -ENOMEM);
+                        crypt_dec_pending(io, -ENOMEM);
                         return;
                 }
 
@@ -589,7 +608,7 @@ static void process_write(struct dm_crypt_io *io)
                 if (unlikely(crypt_convert(cc, &ctx) < 0)) {
                         crypt_free_buffer_pages(cc, clone);
                         bio_put(clone);
-                        dec_pending(io, -EIO);
+                        crypt_dec_pending(io, -EIO);
                         return;
                 }
 
@@ -624,17 +643,23 @@ static void process_read_endio(struct dm_crypt_io *io)
         crypt_convert_init(cc, &ctx, io->base_bio, io->base_bio,
                            io->base_bio->bi_sector - io->target->begin, 0);
 
-        dec_pending(io, crypt_convert(cc, &ctx));
+        crypt_dec_pending(io, crypt_convert(cc, &ctx));
 }
 
 static void kcryptd_do_work(struct work_struct *work)
 {
         struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
 
-        if (io->post_process)
-                process_read_endio(io);
-        else if (bio_data_dir(io->base_bio) == READ)
+        if (bio_data_dir(io->base_bio) == READ)
                 process_read(io);
+}
+
+static void kcryptd_do_crypt(struct work_struct *work)
+{
+        struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
+
+        if (bio_data_dir(io->base_bio) == READ)
+                process_read_endio(io);
         else
                 process_write(io);
 }
@@ -690,7 +715,7 @@ static int crypt_set_key(struct crypt_config *cc, char *key)
         cc->key_size = key_size; /* initial settings */
 
         if ((!key_size && strcmp(key, "-")) ||
-            (key_size && crypt_decode_key(cc->key, key, key_size) < 0))
+           (key_size && crypt_decode_key(cc->key, key, key_size) < 0))
                 return -EINVAL;
 
         set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
@@ -746,7 +771,7 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 
         if (crypt_set_key(cc, argv[1])) {
                 ti->error = "Error decoding key";
-                goto bad1;
+                goto bad_cipher;
         }
 
         /* Compatiblity mode for old dm-crypt cipher strings */
@@ -757,19 +782,19 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 
         if (strcmp(chainmode, "ecb") && !ivmode) {
                 ti->error = "This chaining mode requires an IV mechanism";
-                goto bad1;
+                goto bad_cipher;
         }
 
-        if (snprintf(cc->cipher, CRYPTO_MAX_ALG_NAME, "%s(%s)", chainmode, 
-                     cipher) >= CRYPTO_MAX_ALG_NAME) {
+        if (snprintf(cc->cipher, CRYPTO_MAX_ALG_NAME, "%s(%s)",
+                     chainmode, cipher) >= CRYPTO_MAX_ALG_NAME) {
                 ti->error = "Chain mode + cipher name is too long";
-                goto bad1;
+                goto bad_cipher;
         }
 
         tfm = crypto_alloc_blkcipher(cc->cipher, 0, CRYPTO_ALG_ASYNC);
         if (IS_ERR(tfm)) {
                 ti->error = "Error allocating crypto tfm";
-                goto bad1;
+                goto bad_cipher;
         }
 
         strcpy(cc->cipher, cipher);
@@ -793,18 +818,18 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
                 cc->iv_gen_ops = &crypt_iv_null_ops;
         else {
                 ti->error = "Invalid IV mode";
-                goto bad2;
+                goto bad_ivmode;
         }
 
         if (cc->iv_gen_ops && cc->iv_gen_ops->ctr &&
             cc->iv_gen_ops->ctr(cc, ti, ivopts) < 0)
-                goto bad2;
+                goto bad_ivmode;
 
         cc->iv_size = crypto_blkcipher_ivsize(tfm);
         if (cc->iv_size)
                 /* at least a 64 bit sector number should fit in our buffer */
                 cc->iv_size = max(cc->iv_size,
-                                  (unsigned int)(sizeof(u64) / sizeof(u8)));
+                                  (unsigned int)(sizeof(u64) / sizeof(u8)));
         else {
                 if (cc->iv_gen_ops) {
                         DMWARN("Selected cipher does not support IVs");
@@ -817,13 +842,13 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
         cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool);
         if (!cc->io_pool) {
                 ti->error = "Cannot allocate crypt io mempool";
-                goto bad3;
+                goto bad_slab_pool;
         }
 
         cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0);
         if (!cc->page_pool) {
                 ti->error = "Cannot allocate page mempool";
-                goto bad4;
+                goto bad_page_pool;
         }
 
         cc->bs = bioset_create(MIN_IOS, MIN_IOS);
@@ -834,25 +859,25 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 
         if (crypto_blkcipher_setkey(tfm, cc->key, key_size) < 0) {
                 ti->error = "Error setting key";
-                goto bad5;
+                goto bad_device;
         }
 
         if (sscanf(argv[2], "%llu", &tmpll) != 1) {
                 ti->error = "Invalid iv_offset sector";
-                goto bad5;
+                goto bad_device;
         }
         cc->iv_offset = tmpll;
 
         if (sscanf(argv[4], "%llu", &tmpll) != 1) {
                 ti->error = "Invalid device sector";
-                goto bad5;
+                goto bad_device;
         }
         cc->start = tmpll;
 
         if (dm_get_device(ti, argv[3], cc->start, ti->len,
-                          dm_table_get_mode(ti->table), &cc->dev)) {
+                          dm_table_get_mode(ti->table), &cc->dev)) {
                 ti->error = "Device lookup failed";
-                goto bad5;
+                goto bad_device;
         }
 
         if (ivmode && cc->iv_gen_ops) {
@@ -861,27 +886,45 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
                 cc->iv_mode = kmalloc(strlen(ivmode) + 1, GFP_KERNEL);
                 if (!cc->iv_mode) {
                         ti->error = "Error kmallocing iv_mode string";
-                        goto bad5;
+                        goto bad_ivmode_string;
                 }
                 strcpy(cc->iv_mode, ivmode);
         } else
                 cc->iv_mode = NULL;
 
+        cc->io_queue = create_singlethread_workqueue("kcryptd_io");
+        if (!cc->io_queue) {
+                ti->error = "Couldn't create kcryptd io queue";
+                goto bad_io_queue;
+        }
+
+        cc->crypt_queue = create_singlethread_workqueue("kcryptd");
+        if (!cc->crypt_queue) {
+                ti->error = "Couldn't create kcryptd queue";
+                goto bad_crypt_queue;
+        }
+
         ti->private = cc;
         return 0;
 
-bad5:
+bad_crypt_queue:
+        destroy_workqueue(cc->io_queue);
+bad_io_queue:
+        kfree(cc->iv_mode);
+bad_ivmode_string:
+        dm_put_device(ti, cc->dev);
+bad_device:
         bioset_free(cc->bs);
 bad_bs:
         mempool_destroy(cc->page_pool);
-bad4:
+bad_page_pool:
         mempool_destroy(cc->io_pool);
-bad3:
+bad_slab_pool:
         if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
                 cc->iv_gen_ops->dtr(cc);
-bad2:
+bad_ivmode:
         crypto_free_blkcipher(tfm);
-bad1:
+bad_cipher:
         /* Must zero key material before freeing */
         memset(cc, 0, sizeof(*cc) + cc->key_size * sizeof(u8));
         kfree(cc);
@@ -892,7 +935,8 @@ static void crypt_dtr(struct dm_target *ti)
 {
         struct crypt_config *cc = (struct crypt_config *) ti->private;
 
-        flush_workqueue(_kcryptd_workqueue);
+        destroy_workqueue(cc->io_queue);
+        destroy_workqueue(cc->crypt_queue);
 
         bioset_free(cc->bs);
         mempool_destroy(cc->page_pool);
@@ -918,9 +962,13 @@ static int crypt_map(struct dm_target *ti, struct bio *bio,
         io = mempool_alloc(cc->io_pool, GFP_NOIO);
         io->target = ti;
         io->base_bio = bio;
-        io->error = io->post_process = 0;
+        io->error = 0;
         atomic_set(&io->pending, 0);
-        kcryptd_queue_io(io);
+
+        if (bio_data_dir(io->base_bio) == READ)
+                kcryptd_queue_io(io);
+        else
+                kcryptd_queue_crypt(io);
 
         return DM_MAPIO_SUBMITTED;
 }
@@ -1037,25 +1085,12 @@ static int __init dm_crypt_init(void)
         if (!_crypt_io_pool)
                 return -ENOMEM;
 
-        _kcryptd_workqueue = create_workqueue("kcryptd");
-        if (!_kcryptd_workqueue) {
-                r = -ENOMEM;
-                DMERR("couldn't create kcryptd");
-                goto bad1;
-        }
-
         r = dm_register_target(&crypt_target);
         if (r < 0) {
                 DMERR("register failed %d", r);
-                goto bad2;
+                kmem_cache_destroy(_crypt_io_pool);
         }
 
-        return 0;
-
-bad2:
-        destroy_workqueue(_kcryptd_workqueue);
-bad1:
-        kmem_cache_destroy(_crypt_io_pool);
         return r;
 }
 
@@ -1066,7 +1101,6 @@ static void __exit dm_crypt_exit(void)
         if (r < 0)
                 DMERR("unregister failed %d", r);
 
-        destroy_workqueue(_kcryptd_workqueue);
         kmem_cache_destroy(_crypt_io_pool);
 }
 
diff --git a/drivers/md/dm-delay.c b/drivers/md/dm-delay.c
index 6928c136d3c5..bdd37f881c42 100644
--- a/drivers/md/dm-delay.c
+++ b/drivers/md/dm-delay.c
@@ -83,7 +83,7 @@ static struct bio *flush_delayed_bios(struct delay_c *dc, int flush_all)
         struct dm_delay_info *delayed, *next;
         unsigned long next_expires = 0;
         int start_timer = 0;
-        BIO_LIST(flush_bios);
+        struct bio_list flush_bios = { };
 
         mutex_lock(&delayed_bios_lock);
         list_for_each_entry_safe(delayed, next, &dc->delayed_bios, list) {
@@ -163,34 +163,32 @@ static int delay_ctr(struct dm_target *ti, unsigned int argc, char **argv)
                 goto bad;
         }
 
-        if (argc == 3) {
-                dc->dev_write = NULL;
+        dc->dev_write = NULL;
+        if (argc == 3)
                 goto out;
-        }
 
         if (sscanf(argv[4], "%llu", &tmpll) != 1) {
                 ti->error = "Invalid write device sector";
-                goto bad;
+                goto bad_dev_read;
         }
         dc->start_write = tmpll;
 
         if (sscanf(argv[5], "%u", &dc->write_delay) != 1) {
                 ti->error = "Invalid write delay";
-                goto bad;
+                goto bad_dev_read;
         }
 
         if (dm_get_device(ti, argv[3], dc->start_write, ti->len,
                           dm_table_get_mode(ti->table), &dc->dev_write)) {
                 ti->error = "Write device lookup failed";
-                dm_put_device(ti, dc->dev_read);
-                goto bad;
+                goto bad_dev_read;
         }
 
 out:
         dc->delayed_pool = mempool_create_slab_pool(128, delayed_cache);
         if (!dc->delayed_pool) {
                 DMERR("Couldn't create delayed bio pool.");
-                goto bad;
+                goto bad_dev_write;
         }
 
         setup_timer(&dc->delay_timer, handle_delayed_timer, (unsigned long)dc);
@@ -203,6 +201,11 @@ out:
         ti->private = dc;
         return 0;
 
+bad_dev_write:
+        if (dc->dev_write)
+                dm_put_device(ti, dc->dev_write);
+bad_dev_read:
+        dm_put_device(ti, dc->dev_read);
 bad:
         kfree(dc);
         return -EINVAL;
@@ -305,7 +308,7 @@ static int delay_status(struct dm_target *ti, status_type_t type,
                        (unsigned long long) dc->start_read,
                        dc->read_delay);
                 if (dc->dev_write)
-                        DMEMIT("%s %llu %u", dc->dev_write->name,
+                        DMEMIT(" %s %llu %u", dc->dev_write->name,
                                (unsigned long long) dc->start_write,
                                dc->write_delay);
                 break;
diff --git a/drivers/md/dm-emc.c b/drivers/md/dm-emc.c
index 342517261ece..6b91b9ab1d41 100644
--- a/drivers/md/dm-emc.c
+++ b/drivers/md/dm-emc.c
@@ -81,7 +81,7 @@ static struct bio *get_failover_bio(struct dm_path *path, unsigned data_size)
         }
 
         if (bio_add_page(bio, page, data_size, 0) != data_size) {
-                DMERR("get_failover_bio: alloc_page() failed.");
+                DMERR("get_failover_bio: bio_add_page() failed.");
                 __free_page(page);
                 bio_put(bio);
                 return NULL;
@@ -211,12 +211,10 @@ fail_path:
 
 static struct emc_handler *alloc_emc_handler(void)
 {
-        struct emc_handler *h = kmalloc(sizeof(*h), GFP_KERNEL);
+        struct emc_handler *h = kzalloc(sizeof(*h), GFP_KERNEL);
 
-        if (h) {
-                memset(h, 0, sizeof(*h));
+        if (h)
                 spin_lock_init(&h->lock);
-        }
 
         return h;
 }
diff --git a/drivers/md/dm-hw-handler.c b/drivers/md/dm-hw-handler.c
index baafaaba4d4b..2ee84d8aa0bf 100644
--- a/drivers/md/dm-hw-handler.c
+++ b/drivers/md/dm-hw-handler.c
@@ -91,12 +91,10 @@ void dm_put_hw_handler(struct hw_handler_type *hwht)
 
 static struct hwh_internal *_alloc_hw_handler(struct hw_handler_type *hwht)
 {
-        struct hwh_internal *hwhi = kmalloc(sizeof(*hwhi), GFP_KERNEL);
+        struct hwh_internal *hwhi = kzalloc(sizeof(*hwhi), GFP_KERNEL);
 
-        if (hwhi) {
-                memset(hwhi, 0, sizeof(*hwhi));
+        if (hwhi)
                 hwhi->hwht = *hwht;
-        }
 
         return hwhi;
 }
diff --git a/drivers/md/dm-hw-handler.h b/drivers/md/dm-hw-handler.h
index e0832e6fcf36..46809dcb121a 100644
--- a/drivers/md/dm-hw-handler.h
+++ b/drivers/md/dm-hw-handler.h
@@ -58,5 +58,6 @@ unsigned dm_scsi_err_handler(struct hw_handler *hwh, struct bio *bio);
 #define MP_FAIL_PATH 1
 #define MP_BYPASS_PG 2
 #define MP_ERROR_IO  4  /* Don't retry this I/O */
+#define MP_RETRY 8
 
 #endif
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index b441d82c338a..138200bf5e0b 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -700,7 +700,7 @@ static int dev_rename(struct dm_ioctl *param, size_t param_size)
         int r;
         char *new_name = (char *) param + param->data_start;
 
-        if (new_name < (char *) (param + 1) ||
+        if (new_name < (char *) param->data ||
             invalid_str(new_name, (void *) param + param_size)) {
                 DMWARN("Invalid new logical volume name supplied.");
                 return -EINVAL;
@@ -726,7 +726,7 @@ static int dev_set_geometry(struct dm_ioctl *param, size_t param_size)
         if (!md)
                 return -ENXIO;
 
-        if (geostr < (char *) (param + 1) ||
+        if (geostr < (char *) param->data ||
             invalid_str(geostr, (void *) param + param_size)) {
                 DMWARN("Invalid geometry supplied.");
                 goto out;
@@ -1233,7 +1233,7 @@ static int target_message(struct dm_ioctl *param, size_t param_size)
         if (r)
                 goto out;
 
-        if (tmsg < (struct dm_target_msg *) (param + 1) ||
+        if (tmsg < (struct dm_target_msg *) param->data ||
             invalid_str(tmsg->message, (void *) param + param_size)) {
                 DMWARN("Invalid target message parameters.");
                 r = -EINVAL;
@@ -1358,7 +1358,7 @@ static int copy_params(struct dm_ioctl __user *user, struct dm_ioctl **param)
         if (tmp.data_size < sizeof(tmp))
                 return -EINVAL;
 
-        dmi = (struct dm_ioctl *) vmalloc(tmp.data_size);
+        dmi = vmalloc(tmp.data_size);
         if (!dmi)
                 return -ENOMEM;
 
@@ -1515,3 +1515,35 @@ void dm_interface_exit(void)
 
         dm_hash_exit();
 }
+
+/**
+ * dm_copy_name_and_uuid - Copy mapped device name & uuid into supplied buffers
+ * @md: Pointer to mapped_device
+ * @name: Buffer (size DM_NAME_LEN) for name
+ * @uuid: Buffer (size DM_UUID_LEN) for uuid or empty string if uuid not defined
+ */
+int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid)
+{
+        int r = 0;
+        struct hash_cell *hc;
+
+        if (!md)
+                return -ENXIO;
+
+        dm_get(md);
+        down_read(&_hash_lock);
+        hc = dm_get_mdptr(md);
+        if (!hc || hc->md != md) {
+                r = -ENXIO;
+                goto out;
+        }
+
+        strcpy(name, hc->name);
+        strcpy(uuid, hc->uuid ? : "");
+
+out:
+        up_read(&_hash_lock);
+        dm_put(md);
+
+        return r;
+}
diff --git a/drivers/md/dm-log.c b/drivers/md/dm-log.c
index a66428d860fe..072ee4353eab 100644
--- a/drivers/md/dm-log.c
+++ b/drivers/md/dm-log.c
@@ -696,7 +696,7 @@ static struct dirty_log_type _disk_type = {
         .module = THIS_MODULE,
         .ctr = disk_ctr,
         .dtr = disk_dtr,
-        .suspend = disk_flush,
+        .postsuspend = disk_flush,
         .resume = disk_resume,
         .get_region_size = core_get_region_size,
         .is_clean = core_is_clean,
diff --git a/drivers/md/dm-log.h b/drivers/md/dm-log.h
index 86a301c8daf1..3fae87eb5963 100644
--- a/drivers/md/dm-log.h
+++ b/drivers/md/dm-log.h
@@ -32,7 +32,8 @@ struct dirty_log_type {
          * There are times when we don't want the log to touch
          * the disk.
          */
-        int (*suspend)(struct dirty_log *log);
+        int (*presuspend)(struct dirty_log *log);
+        int (*postsuspend)(struct dirty_log *log);
         int (*resume)(struct dirty_log *log);
 
         /*
diff --git a/drivers/md/dm-mpath-hp-sw.c b/drivers/md/dm-mpath-hp-sw.c
new file mode 100644
index 000000000000..204bf42c9449
--- /dev/null
+++ b/drivers/md/dm-mpath-hp-sw.c
@@ -0,0 +1,248 @@
+/*
+ * Copyright (C) 2005 Mike Christie, All rights reserved.
+ * Copyright (C) 2007 Red Hat, Inc. All rights reserved.
+ * Authors: Mike Christie
+ *          Dave Wysochanski
+ *
+ * This file is released under the GPL.
+ *
+ * This module implements the specific path activation code for
+ * HP StorageWorks and FSC FibreCat Asymmetric (Active/Passive)
+ * storage arrays.
+ * These storage arrays have controller-based failover, not
+ * LUN-based failover.  However, LUN-based failover is the design
+ * of dm-multipath. Thus, this module is written for LUN-based failover.
+ */
+#include <linux/blkdev.h>
+#include <linux/list.h>
+#include <linux/types.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_dbg.h>
+
+#include "dm.h"
+#include "dm-hw-handler.h"
+
+#define DM_MSG_PREFIX "multipath hp-sw"
+#define DM_HP_HWH_NAME "hp-sw"
+#define DM_HP_HWH_VER "1.0.0"
+
+struct hp_sw_context {
+        unsigned char sense[SCSI_SENSE_BUFFERSIZE];
+};
+
+/*
+ * hp_sw_error_is_retryable - Is an HP-specific check condition retryable?
+ * @req: path activation request
+ *
+ * Examine error codes of request and determine whether the error is retryable.
+ * Some error codes are already retried by scsi-ml (see
+ * scsi_decide_disposition), but some HP specific codes are not.
+ * The intent of this routine is to supply the logic for the HP specific
+ * check conditions.
+ *
+ * Returns:
+ *  1 - command completed with retryable error
+ *  0 - command completed with non-retryable error
+ *
+ * Possible optimizations
+ * 1. More hardware-specific error codes
+ */
+static int hp_sw_error_is_retryable(struct request *req)
+{
+        /*
+         * NOT_READY is known to be retryable
+         * For now we just dump out the sense data and call it retryable
+         */
+        if (status_byte(req->errors) == CHECK_CONDITION)
+                __scsi_print_sense(DM_HP_HWH_NAME, req->sense, req->sense_len);
+
+        /*
+         * At this point we don't have complete information about all the error
+         * codes from this hardware, so we are just conservative and retry
+         * when in doubt.
+         */
+        return 1;
+}
+
+/*
+ * hp_sw_end_io - Completion handler for HP path activation.
+ * @req: path activation request
+ * @error: scsi-ml error
+ *
+ *  Check sense data, free request structure, and notify dm that
+ *  pg initialization has completed.
+ *
+ * Context: scsi-ml softirq
+ *
+ */
+static void hp_sw_end_io(struct request *req, int error)
+{
+        struct dm_path *path = req->end_io_data;
+        unsigned err_flags = 0;
+
+        if (!error) {
+                DMDEBUG("%s path activation command - success",
+                        path->dev->name);
+                goto out;
+        }
+
+        if (hp_sw_error_is_retryable(req)) {
+                DMDEBUG("%s path activation command - retry",
+                        path->dev->name);
+                err_flags = MP_RETRY;
+                goto out;
+        }
+
+        DMWARN("%s path activation fail - error=0x%x",
+               path->dev->name, error);
+        err_flags = MP_FAIL_PATH;
+
+out:
+        req->end_io_data = NULL;
+        __blk_put_request(req->q, req);
+        dm_pg_init_complete(path, err_flags);
+}
+
+/*
+ * hp_sw_get_request - Allocate an HP specific path activation request
+ * @path: path on which request will be sent (needed for request queue)
+ *
+ * The START command is used for path activation request.
+ * These arrays are controller-based failover, not LUN based.
+ * One START command issued to a single path will fail over all
+ * LUNs for the same controller.
+ *
+ * Possible optimizations
+ * 1. Make timeout configurable
+ * 2. Preallocate request
+ */
+static struct request *hp_sw_get_request(struct dm_path *path)
+{
+        struct request *req;
+        struct block_device *bdev = path->dev->bdev;
+        struct request_queue *q = bdev_get_queue(bdev);
+        struct hp_sw_context *h = path->hwhcontext;
+
+        req = blk_get_request(q, WRITE, GFP_NOIO);
+        if (!req)
+                goto out;
+
+        req->timeout = 60 * HZ;
+
+        req->errors = 0;
+        req->cmd_type = REQ_TYPE_BLOCK_PC;
+        req->cmd_flags |= REQ_FAILFAST | REQ_NOMERGE;
+        req->end_io_data = path;
+        req->sense = h->sense;
+        memset(req->sense, 0, SCSI_SENSE_BUFFERSIZE);
+
+        memset(&req->cmd, 0, BLK_MAX_CDB);
+        req->cmd[0] = START_STOP;
+        req->cmd[4] = 1;
+        req->cmd_len = COMMAND_SIZE(req->cmd[0]);
+
+out:
+        return req;
+}
+
+/*
+ * hp_sw_pg_init - HP path activation implementation.
+ * @hwh: hardware handler specific data
+ * @bypassed: unused; is the path group bypassed? (see dm-mpath.c)
+ * @path: path to send initialization command
+ *
+ * Send an HP-specific path activation command on 'path'.
+ * Do not try to optimize in any way, just send the activation command.
+ * More than one path activation command may be sent to the same controller.
+ * This seems to work fine for basic failover support.
+ *
+ * Possible optimizations
+ * 1. Detect an in-progress activation request and avoid submitting another one
+ * 2. Model the controller and only send a single activation request at a time
+ * 3. Determine the state of a path before sending an activation request
+ *
+ * Context: kmpathd (see process_queued_ios() in dm-mpath.c)
+ */
+static void hp_sw_pg_init(struct hw_handler *hwh, unsigned bypassed,
+                          struct dm_path *path)
+{
+        struct request *req;
+        struct hp_sw_context *h;
+
+        path->hwhcontext = hwh->context;
+        h = hwh->context;
+
+        req = hp_sw_get_request(path);
+        if (!req) {
+                DMERR("%s path activation command - allocation fail",
+                      path->dev->name);
+                goto retry;
+        }
+
+        DMDEBUG("%s path activation command - sent", path->dev->name);
+
+        blk_execute_rq_nowait(req->q, NULL, req, 1, hp_sw_end_io);
+        return;
+
+retry:
+        dm_pg_init_complete(path, MP_RETRY);
+}
+
+static int hp_sw_create(struct hw_handler *hwh, unsigned argc, char **argv)
+{
+        struct hp_sw_context *h;
+
+        h = kmalloc(sizeof(*h), GFP_KERNEL);
+        if (!h)
+                return -ENOMEM;
+
+        hwh->context = h;
+
+        return 0;
+}
+
+static void hp_sw_destroy(struct hw_handler *hwh)
+{
+        struct hp_sw_context *h = hwh->context;
+
+        kfree(h);
+}
+
+static struct hw_handler_type hp_sw_hwh = {
+        .name = DM_HP_HWH_NAME,
+        .module = THIS_MODULE,
+        .create = hp_sw_create,
+        .destroy = hp_sw_destroy,
+        .pg_init = hp_sw_pg_init,
+};
+
+static int __init hp_sw_init(void)
+{
+        int r;
+
+        r = dm_register_hw_handler(&hp_sw_hwh);
+        if (r < 0)
+                DMERR("register failed %d", r);
+        else
+                DMINFO("version " DM_HP_HWH_VER " loaded");
+
+        return r;
+}
+
+static void __exit hp_sw_exit(void)
+{
+        int r;
+
+        r = dm_unregister_hw_handler(&hp_sw_hwh);
+        if (r < 0)
+                DMERR("unregister failed %d", r);
+}
+
+module_init(hp_sw_init);
+module_exit(hp_sw_exit);
+
+MODULE_DESCRIPTION("DM Multipath HP StorageWorks / FSC FibreCat (A/P) support");
+MODULE_AUTHOR("Mike Christie, Dave Wysochanski <dm-devel@redhat.com>");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DM_HP_HWH_VER);
diff --git a/drivers/md/dm-mpath-rdac.c b/drivers/md/dm-mpath-rdac.c
index 16b161345775..e04eb5c697fb 100644
--- a/drivers/md/dm-mpath-rdac.c
+++ b/drivers/md/dm-mpath-rdac.c
@@ -664,20 +664,21 @@ static struct hw_handler_type rdac_handler = {
 
 static int __init rdac_init(void)
 {
-        int r = dm_register_hw_handler(&rdac_handler);
-
-        if (r < 0) {
-                DMERR("%s: register failed %d", RDAC_DM_HWH_NAME, r);
-                return r;
-        }
+        int r;
 
         rdac_wkqd = create_singlethread_workqueue("rdac_wkqd");
         if (!rdac_wkqd) {
                 DMERR("Failed to create workqueue rdac_wkqd.");
-                dm_unregister_hw_handler(&rdac_handler);
                 return -ENOMEM;
         }
 
+        r = dm_register_hw_handler(&rdac_handler);
+        if (r < 0) {
+                DMERR("%s: register failed %d", RDAC_DM_HWH_NAME, r);
+                destroy_workqueue(rdac_wkqd);
+                return r;
+        }
+
         DMINFO("%s: version %s loaded", RDAC_DM_HWH_NAME, RDAC_DM_HWH_VER);
         return 0;
 }
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 31056abca89d..24b2b1e32fae 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -10,6 +10,7 @@
 #include "dm-hw-handler.h"
 #include "dm-bio-list.h"
 #include "dm-bio-record.h"
+#include "dm-uevent.h"
 
 #include <linux/ctype.h>
 #include <linux/init.h>
@@ -75,6 +76,8 @@ struct multipath {
         unsigned queue_io;              /* Must we queue all I/O? */
         unsigned queue_if_no_path;      /* Queue I/O if last path fails? */
         unsigned saved_queue_if_no_path;/* Saved state during suspension */
+        unsigned pg_init_retries;       /* Number of times to retry pg_init */
+        unsigned pg_init_count;         /* Number of times pg_init called */
 
         struct work_struct process_queued_ios;
         struct bio_list queued_ios;
@@ -225,6 +228,8 @@ static void __switch_pg(struct multipath *m, struct pgpath *pgpath)
                 m->pg_init_required = 0;
                 m->queue_io = 0;
         }
+
+        m->pg_init_count = 0;
 }
 
 static int __choose_path_in_pg(struct multipath *m, struct priority_group *pg)
@@ -424,6 +429,7 @@ static void process_queued_ios(struct work_struct *work)
                 must_queue = 0;
 
         if (m->pg_init_required && !m->pg_init_in_progress) {
+                m->pg_init_count++;
                 m->pg_init_required = 0;
                 m->pg_init_in_progress = 1;
                 init_required = 1;
@@ -689,9 +695,11 @@ static int parse_features(struct arg_set *as, struct multipath *m)
         int r;
         unsigned argc;
         struct dm_target *ti = m->ti;
+        const char *param_name;
 
         static struct param _params[] = {
-                {0, 1, "invalid number of feature args"},
+                {0, 3, "invalid number of feature args"},
+                {1, 50, "pg_init_retries must be between 1 and 50"},
         };
 
         r = read_param(_params, shift(as), &argc, &ti->error);
@@ -701,12 +709,28 @@ static int parse_features(struct arg_set *as, struct multipath *m)
         if (!argc)
                 return 0;
 
-        if (!strnicmp(shift(as), MESG_STR("queue_if_no_path")))
-                return queue_if_no_path(m, 1, 0);
-        else {
+        do {
+                param_name = shift(as);
+                argc--;
+
+                if (!strnicmp(param_name, MESG_STR("queue_if_no_path"))) {
+                        r = queue_if_no_path(m, 1, 0);
+                        continue;
+                }
+
+                if (!strnicmp(param_name, MESG_STR("pg_init_retries")) &&
+                    (argc >= 1)) {
+                        r = read_param(_params + 1, shift(as),
+                                       &m->pg_init_retries, &ti->error);
+                        argc--;
+                        continue;
+                }
+
                 ti->error = "Unrecognised multipath feature request";
-                return -EINVAL;
-        }
+                r = -EINVAL;
+        } while (argc && !r);
+
+        return r;
 }
 
 static int multipath_ctr(struct dm_target *ti, unsigned int argc,
@@ -834,6 +858,9 @@ static int fail_path(struct pgpath *pgpath)
         if (pgpath == m->current_pgpath)
                 m->current_pgpath = NULL;
 
+        dm_path_uevent(DM_UEVENT_PATH_FAILED, m->ti,
+                      pgpath->path.dev->name, m->nr_valid_paths);
+
         queue_work(kmultipathd, &m->trigger_event);
 
 out:
@@ -873,6 +900,9 @@ static int reinstate_path(struct pgpath *pgpath)
         if (!m->nr_valid_paths++ && m->queue_size)
                 queue_work(kmultipathd, &m->process_queued_ios);
 
+        dm_path_uevent(DM_UEVENT_PATH_REINSTATED, m->ti,
+                      pgpath->path.dev->name, m->nr_valid_paths);
+
         queue_work(kmultipathd, &m->trigger_event);
 
 out:
@@ -976,6 +1006,26 @@ static int bypass_pg_num(struct multipath *m, const char *pgstr, int bypassed)
 }
 
 /*
+ * Should we retry pg_init immediately?
+ */
+static int pg_init_limit_reached(struct multipath *m, struct pgpath *pgpath)
+{
+        unsigned long flags;
+        int limit_reached = 0;
+
+        spin_lock_irqsave(&m->lock, flags);
+
+        if (m->pg_init_count <= m->pg_init_retries)
+                m->pg_init_required = 1;
+        else
+                limit_reached = 1;
+
+        spin_unlock_irqrestore(&m->lock, flags);
+
+        return limit_reached;
+}
+
+/*
  * pg_init must call this when it has completed its initialisation
  */
 void dm_pg_init_complete(struct dm_path *path, unsigned err_flags)
@@ -985,8 +1035,14 @@ void dm_pg_init_complete(struct dm_path *path, unsigned err_flags)
         struct multipath *m = pg->m;
         unsigned long flags;
 
-        /* We insist on failing the path if the PG is already bypassed. */
-        if (err_flags && pg->bypassed)
+        /*
+         * If requested, retry pg_init until maximum number of retries exceeded.
+         * If retry not requested and PG already bypassed, always fail the path.
+         */
+        if (err_flags & MP_RETRY) {
+                if (pg_init_limit_reached(m, pgpath))
+                        err_flags |= MP_FAIL_PATH;
+        } else if (err_flags && pg->bypassed)
                 err_flags |= MP_FAIL_PATH;
 
         if (err_flags & MP_FAIL_PATH)
@@ -996,7 +1052,7 @@ void dm_pg_init_complete(struct dm_path *path, unsigned err_flags)
                 bypass_pg(m, pg, 1);
 
         spin_lock_irqsave(&m->lock, flags);
-        if (err_flags) {
+        if (err_flags & ~MP_RETRY) {
                 m->current_pgpath = NULL;
                 m->current_pg = NULL;
         } else if (!m->pg_init_required)
@@ -1148,11 +1204,15 @@ static int multipath_status(struct dm_target *ti, status_type_t type,
 
         /* Features */
         if (type == STATUSTYPE_INFO)
-                DMEMIT("1 %u ", m->queue_size);
-        else if (m->queue_if_no_path)
-                DMEMIT("1 queue_if_no_path ");
-        else
-                DMEMIT("0 ");
+                DMEMIT("2 %u %u ", m->queue_size, m->pg_init_count);
+        else {
+                DMEMIT("%u ", m->queue_if_no_path +
+                              (m->pg_init_retries > 0) * 2);
+                if (m->queue_if_no_path)
+                        DMEMIT("queue_if_no_path ");
+                if (m->pg_init_retries)
+                        DMEMIT("pg_init_retries %u ", m->pg_init_retries);
+        }
 
         if (hwh->type && hwh->type->status)
                 sz += hwh->type->status(hwh, type, result + sz, maxlen - sz);
diff --git a/drivers/md/dm-path-selector.c b/drivers/md/dm-path-selector.c
index f10a0c89b3f4..ca1bb636a3e4 100644
--- a/drivers/md/dm-path-selector.c
+++ b/drivers/md/dm-path-selector.c
@@ -94,12 +94,10 @@ out:
 
 static struct ps_internal *_alloc_path_selector(struct path_selector_type *pst)
 {
-        struct ps_internal *psi = kmalloc(sizeof(*psi), GFP_KERNEL);
+        struct ps_internal *psi = kzalloc(sizeof(*psi), GFP_KERNEL);
 
-        if (psi) {
-                memset(psi, 0, sizeof(*psi));
+        if (psi)
                 psi->pst = *pst;
-        }
 
         return psi;
 }
diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c
index d09ff15490a5..31123d4a6b9c 100644
--- a/drivers/md/dm-raid1.c
+++ b/drivers/md/dm-raid1.c
@@ -19,6 +19,7 @@
 #include <linux/time.h>
 #include <linux/vmalloc.h>
 #include <linux/workqueue.h>
+#include <linux/log2.h>
 
 #define DM_MSG_PREFIX "raid1"
 #define DM_IO_PAGES 64
@@ -113,6 +114,7 @@ struct region {
  * Mirror set structures.
  *---------------------------------------------------------------*/
 struct mirror {
+        struct mirror_set *ms;
         atomic_t error_count;
         struct dm_dev *dev;
         sector_t offset;
@@ -974,6 +976,7 @@ static struct mirror_set *alloc_context(unsigned int nr_mirrors,
 
         if (rh_init(&ms->rh, ms, dl, region_size, ms->nr_regions)) {
                 ti->error = "Error creating dirty region hash";
+                dm_io_client_destroy(ms->io_client);
                 kfree(ms);
                 return NULL;
         }
@@ -994,7 +997,7 @@ static void free_context(struct mirror_set *ms, struct dm_target *ti,
 
 static inline int _check_region_size(struct dm_target *ti, uint32_t size)
 {
-        return !(size % (PAGE_SIZE >> 9) || (size & (size - 1)) ||
+        return !(size % (PAGE_SIZE >> 9) || !is_power_of_2(size) ||
                  size > ti->len);
 }
 
@@ -1015,6 +1018,7 @@ static int get_mirror(struct mirror_set *ms, struct dm_target *ti,
                 return -ENXIO;
         }
 
+        ms->mirror[mirror].ms = ms;
         ms->mirror[mirror].offset = offset;
 
         return 0;
@@ -1163,16 +1167,14 @@ static int mirror_ctr(struct dm_target *ti, unsigned int argc, char **argv)
         ms->kmirrord_wq = create_singlethread_workqueue("kmirrord");
         if (!ms->kmirrord_wq) {
                 DMERR("couldn't start kmirrord");
-                free_context(ms, ti, m);
-                return -ENOMEM;
+                r = -ENOMEM;
+                goto err_free_context;
         }
         INIT_WORK(&ms->kmirrord_work, do_mirror);
 
         r = parse_features(ms, argc, argv, &args_used);
-        if (r) {
-                free_context(ms, ti, ms->nr_mirrors);
-                return r;
-        }
+        if (r)
+                goto err_destroy_wq;
 
         argv += args_used;
         argc -= args_used;
@@ -1188,19 +1190,22 @@ static int mirror_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 
         if (argc) {
                 ti->error = "Too many mirror arguments";
-                free_context(ms, ti, ms->nr_mirrors);
-                return -EINVAL;
+                r = -EINVAL;
+                goto err_destroy_wq;
         }
 
         r = kcopyd_client_create(DM_IO_PAGES, &ms->kcopyd_client);
-        if (r) {
-                destroy_workqueue(ms->kmirrord_wq);
-                free_context(ms, ti, ms->nr_mirrors);
-                return r;
-        }
+        if (r)
+                goto err_destroy_wq;
 
         wake(ms);
         return 0;
+
+err_destroy_wq:
+        destroy_workqueue(ms->kmirrord_wq);
+err_free_context:
+        free_context(ms, ti, ms->nr_mirrors);
+        return r;
 }
 
 static void mirror_dtr(struct dm_target *ti)
@@ -1302,7 +1307,7 @@ static void mirror_postsuspend(struct dm_target *ti)
         wait_event(_kmirrord_recovery_stopped,
                    !atomic_read(&ms->rh.recovery_in_flight));
 
-        if (log->type->suspend && log->type->suspend(log))
+        if (log->type->postsuspend && log->type->postsuspend(log))
                 /* FIXME: need better error handling */
                 DMWARN("log suspend failed");
 }
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index 98a633f3d6b0..cee16fadd9ee 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -17,6 +17,7 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/vmalloc.h>
+#include <linux/log2.h>
 
 #include "dm-snap.h"
 #include "dm-bio-list.h"
@@ -415,7 +416,7 @@ static int set_chunk_size(struct dm_snapshot *s, const char *chunk_size_arg,
         chunk_size = round_up(chunk_size, PAGE_SIZE >> 9);
 
         /* Check chunk_size is a power of 2 */
-        if (chunk_size & (chunk_size - 1)) {
+        if (!is_power_of_2(chunk_size)) {
                 *error = "Chunk size is not a power of 2";
                 return -EINVAL;
         }
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index 51f5e0760012..969944a8aba2 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -11,6 +11,7 @@
 #include <linux/blkdev.h>
 #include <linux/bio.h>
 #include <linux/slab.h>
+#include <linux/log2.h>
 
 #define DM_MSG_PREFIX "striped"
 
@@ -99,7 +100,7 @@ static int stripe_ctr(struct dm_target *ti, unsigned int argc, char **argv)
         /*
          * chunk_size is a power of two
          */
-        if (!chunk_size || (chunk_size & (chunk_size - 1)) ||
+        if (!is_power_of_2(chunk_size) ||
             (chunk_size < (PAGE_SIZE >> SECTOR_SHIFT))) {
                 ti->error = "Invalid chunk size";
                 return -EINVAL;
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index fbe477bb2c68..8939e6105088 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -213,12 +213,11 @@ static int alloc_targets(struct dm_table *t, unsigned int num)
 int dm_table_create(struct dm_table **result, int mode,
                     unsigned num_targets, struct mapped_device *md)
 {
-        struct dm_table *t = kmalloc(sizeof(*t), GFP_KERNEL);
+        struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL);
 
         if (!t)
                 return -ENOMEM;
 
-        memset(t, 0, sizeof(*t));
         INIT_LIST_HEAD(&t->devices);
         atomic_set(&t->holders, 1);
 
diff --git a/drivers/md/dm-target.c b/drivers/md/dm-target.c
index 477a041a41cf..835cf95b857f 100644
--- a/drivers/md/dm-target.c
+++ b/drivers/md/dm-target.c
@@ -88,12 +88,10 @@ void dm_put_target_type(struct target_type *t)
 
 static struct tt_internal *alloc_target(struct target_type *t)
 {
-        struct tt_internal *ti = kmalloc(sizeof(*ti), GFP_KERNEL);
+        struct tt_internal *ti = kzalloc(sizeof(*ti), GFP_KERNEL);
 
-        if (ti) {
-                memset(ti, 0, sizeof(*ti));
+        if (ti)
                 ti->tt = *t;
-        }
 
         return ti;
 }
diff --git a/drivers/md/dm-uevent.c b/drivers/md/dm-uevent.c
new file mode 100644
index 000000000000..50377e5dc2a3
--- /dev/null
+++ b/drivers/md/dm-uevent.c
@@ -0,0 +1,222 @@
+/*
+ * Device Mapper Uevent Support (dm-uevent)
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright IBM Corporation, 2007
+ *      Author: Mike Anderson <andmike@linux.vnet.ibm.com>
+ */
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/kobject.h>
+#include <linux/dm-ioctl.h>
+
+#include "dm.h"
+#include "dm-uevent.h"
+
+#define DM_MSG_PREFIX "uevent"
+
+static const struct {
+        enum dm_uevent_type type;
+        enum kobject_action action;
+        char *name;
+} _dm_uevent_type_names[] = {
+        {DM_UEVENT_PATH_FAILED, KOBJ_CHANGE, "PATH_FAILED"},
+        {DM_UEVENT_PATH_REINSTATED, KOBJ_CHANGE, "PATH_REINSTATED"},
+};
+
+static struct kmem_cache *_dm_event_cache;
+
+struct dm_uevent {
+        struct mapped_device *md;
+        enum kobject_action action;
+        struct kobj_uevent_env ku_env;
+        struct list_head elist;
+        char name[DM_NAME_LEN];
+        char uuid[DM_UUID_LEN];
+};
+
+static void dm_uevent_free(struct dm_uevent *event)
+{
+        kmem_cache_free(_dm_event_cache, event);
+}
+
+static struct dm_uevent *dm_uevent_alloc(struct mapped_device *md)
+{
+        struct dm_uevent *event;
+
+        event = kmem_cache_zalloc(_dm_event_cache, GFP_ATOMIC);
+        if (!event)
+                return NULL;
+
+        INIT_LIST_HEAD(&event->elist);
+        event->md = md;
+
+        return event;
+}
+
+static struct dm_uevent *dm_build_path_uevent(struct mapped_device *md,
+                                              struct dm_target *ti,
+                                              enum kobject_action action,
+                                              const char *dm_action,
+                                              const char *path,
+                                              unsigned nr_valid_paths)
+{
+        struct dm_uevent *event;
+
+        event = dm_uevent_alloc(md);
+        if (!event) {
+                DMERR("%s: dm_uevent_alloc() failed", __FUNCTION__);
+                goto err_nomem;
+        }
+
+        event->action = action;
+
+        if (add_uevent_var(&event->ku_env, "DM_TARGET=%s", ti->type->name)) {
+                DMERR("%s: add_uevent_var() for DM_TARGET failed",
+                      __FUNCTION__);
+                goto err_add;
+        }
+
+        if (add_uevent_var(&event->ku_env, "DM_ACTION=%s", dm_action)) {
+                DMERR("%s: add_uevent_var() for DM_ACTION failed",
+                      __FUNCTION__);
+                goto err_add;
+        }
+
+        if (add_uevent_var(&event->ku_env, "DM_SEQNUM=%u",
+                           dm_next_uevent_seq(md))) {
+                DMERR("%s: add_uevent_var() for DM_SEQNUM failed",
+                      __FUNCTION__);
+                goto err_add;
+        }
+
+        if (add_uevent_var(&event->ku_env, "DM_PATH=%s", path)) {
+                DMERR("%s: add_uevent_var() for DM_PATH failed", __FUNCTION__);
+                goto err_add;
+        }
+
+        if (add_uevent_var(&event->ku_env, "DM_NR_VALID_PATHS=%d",
+                           nr_valid_paths)) {
+                DMERR("%s: add_uevent_var() for DM_NR_VALID_PATHS failed",
+                      __FUNCTION__);
+                goto err_add;
+        }
+
+        return event;
+
+err_add:
+        dm_uevent_free(event);
+err_nomem:
+        return ERR_PTR(-ENOMEM);
+}
+
+/**
+ * dm_send_uevents - send uevents for given list
+ *
+ * @events:     list of events to send
+ * @kobj:       kobject generating event
+ *
+ */
+void dm_send_uevents(struct list_head *events, struct kobject *kobj)
+{
+        int r;
+        struct dm_uevent *event, *next;
+
+        list_for_each_entry_safe(event, next, events, elist) {
+                list_del_init(&event->elist);
+
+                /*
+                 * Need to call dm_copy_name_and_uuid from here for now.
+                 * Context of previous var adds and locking used for
+                 * hash_cell not compatable.
+                 */
+                if (dm_copy_name_and_uuid(event->md, event->name,
+                                          event->uuid)) {
+                        DMERR("%s: dm_copy_name_and_uuid() failed",
+                              __FUNCTION__);
+                        goto uevent_free;
+                }
+
+                if (add_uevent_var(&event->ku_env, "DM_NAME=%s", event->name)) {
+                        DMERR("%s: add_uevent_var() for DM_NAME failed",
+                              __FUNCTION__);
+                        goto uevent_free;
+                }
+
+                if (add_uevent_var(&event->ku_env, "DM_UUID=%s", event->uuid)) {
+                        DMERR("%s: add_uevent_var() for DM_UUID failed",
+                              __FUNCTION__);
+                        goto uevent_free;
+                }
+
+                r = kobject_uevent_env(kobj, event->action, event->ku_env.envp);
+                if (r)
+                        DMERR("%s: kobject_uevent_env failed", __FUNCTION__);
+uevent_free:
+                dm_uevent_free(event);
+        }
+}
+EXPORT_SYMBOL_GPL(dm_send_uevents);
+
+/**
+ * dm_path_uevent - called to create a new path event and queue it
+ *
+ * @event_type: path event type enum
+ * @ti:                 pointer to a dm_target
+ * @path:               string containing pathname
+ * @nr_valid_paths:     number of valid paths remaining
+ *
+ */
+void dm_path_uevent(enum dm_uevent_type event_type, struct dm_target *ti,
+                   const char *path, unsigned nr_valid_paths)
+{
+        struct mapped_device *md = dm_table_get_md(ti->table);
+        struct dm_uevent *event;
+
+        if (event_type >= ARRAY_SIZE(_dm_uevent_type_names)) {
+                DMERR("%s: Invalid event_type %d", __FUNCTION__, event_type);
+                goto out;
+        }
+
+        event = dm_build_path_uevent(md, ti,
+                                     _dm_uevent_type_names[event_type].action,
+                                     _dm_uevent_type_names[event_type].name,
+                                     path, nr_valid_paths);
+        if (IS_ERR(event))
+                goto out;
+
+        dm_uevent_add(md, &event->elist);
+
+out:
+        dm_put(md);
+}
+EXPORT_SYMBOL_GPL(dm_path_uevent);
+
+int dm_uevent_init(void)
+{
+        _dm_event_cache = KMEM_CACHE(dm_uevent, 0);
+        if (!_dm_event_cache)
+                return -ENOMEM;
+
+        DMINFO("version 1.0.3");
+
+        return 0;
+}
+
+void dm_uevent_exit(void)
+{
+        kmem_cache_destroy(_dm_event_cache);
+}
diff --git a/drivers/md/dm-uevent.h b/drivers/md/dm-uevent.h
new file mode 100644
index 000000000000..2eccc8bd671a
--- /dev/null
+++ b/drivers/md/dm-uevent.h
@@ -0,0 +1,59 @@
+/*
+ * Device Mapper Uevent Support
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright IBM Corporation, 2007
+ *      Author: Mike Anderson <andmike@linux.vnet.ibm.com>
+ */
+#ifndef DM_UEVENT_H
+#define DM_UEVENT_H
+
+enum dm_uevent_type {
+        DM_UEVENT_PATH_FAILED,
+        DM_UEVENT_PATH_REINSTATED,
+};
+
+#ifdef CONFIG_DM_UEVENT
+
+extern int dm_uevent_init(void);
+extern void dm_uevent_exit(void);
+extern void dm_send_uevents(struct list_head *events, struct kobject *kobj);
+extern void dm_path_uevent(enum dm_uevent_type event_type,
+                           struct dm_target *ti, const char *path,
+                           unsigned nr_valid_paths);
+
+#else
+
+static inline int dm_uevent_init(void)
+{
+        return 0;
+}
+static inline void dm_uevent_exit(void)
+{
+}
+static inline void dm_send_uevents(struct list_head *events,
+                                   struct kobject *kobj)
+{
+}
+static inline void dm_path_uevent(enum dm_uevent_type event_type,
+                                  struct dm_target *ti, const char *path,
+                                  unsigned nr_valid_paths)
+{
+}
+
+#endif  /* CONFIG_DM_UEVENT */
+
+#endif  /* DM_UEVENT_H */
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index d837d37f6209..07cbbb8eb3e0 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -7,6 +7,7 @@
 
 #include "dm.h"
 #include "dm-bio-list.h"
+#include "dm-uevent.h"
 
 #include <linux/init.h>
 #include <linux/module.h>
@@ -112,6 +113,9 @@ struct mapped_device {
          */
         atomic_t event_nr;
         wait_queue_head_t eventq;
+        atomic_t uevent_seq;
+        struct list_head uevent_list;
+        spinlock_t uevent_lock; /* Protect access to uevent_list */
 
         /*
          * freeze/thaw support require holding onto a super block
@@ -143,11 +147,19 @@ static int __init local_init(void)
                 return -ENOMEM;
         }
 
+        r = dm_uevent_init();
+        if (r) {
+                kmem_cache_destroy(_tio_cache);
+                kmem_cache_destroy(_io_cache);
+                return r;
+        }
+
         _major = major;
         r = register_blkdev(_major, _name);
         if (r < 0) {
                 kmem_cache_destroy(_tio_cache);
                 kmem_cache_destroy(_io_cache);
+                dm_uevent_exit();
                 return r;
         }
 
@@ -162,6 +174,7 @@ static void local_exit(void)
         kmem_cache_destroy(_tio_cache);
         kmem_cache_destroy(_io_cache);
         unregister_blkdev(_major, _name);
+        dm_uevent_exit();
 
         _major = 0;
 
@@ -751,15 +764,13 @@ static void __clone_and_map(struct clone_info *ci)
 /*
  * Split the bio into several clones.
  */
-static void __split_bio(struct mapped_device *md, struct bio *bio)
+static int __split_bio(struct mapped_device *md, struct bio *bio)
 {
         struct clone_info ci;
 
         ci.map = dm_get_table(md);
-        if (!ci.map) {
-                bio_io_error(bio);
-                return;
-        }
+        if (unlikely(!ci.map))
+                return -EIO;
 
         ci.md = md;
         ci.bio = bio;
@@ -779,6 +790,8 @@ static void __split_bio(struct mapped_device *md, struct bio *bio)
         /* drop the extra reference count */
         dec_pending(ci.io, 0);
         dm_table_put(ci.map);
+
+        return 0;
 }
 /*-----------------------------------------------------------------
  * CRUD END
@@ -790,7 +803,7 @@ static void __split_bio(struct mapped_device *md, struct bio *bio)
  */
 static int dm_request(struct request_queue *q, struct bio *bio)
 {
-        int r;
+        int r = -EIO;
         int rw = bio_data_dir(bio);
         struct mapped_device *md = q->queuedata;
 
@@ -815,18 +828,11 @@ static int dm_request(struct request_queue *q, struct bio *bio)
         while (test_bit(DMF_BLOCK_IO, &md->flags)) {
                 up_read(&md->io_lock);
 
-                if (bio_rw(bio) == READA) {
-                        bio_io_error(bio);
-                        return 0;
-                }
-
-                r = queue_io(md, bio);
-                if (r < 0) {
-                        bio_io_error(bio);
-                        return 0;
+                if (bio_rw(bio) != READA)
+                        r = queue_io(md, bio);
 
-                } else if (r == 0)
-                        return 0;       /* deferred successfully */
+                if (r <= 0)
+                        goto out_req;
 
                 /*
                  * We're in a while loop, because someone could suspend
@@ -835,8 +841,13 @@ static int dm_request(struct request_queue *q, struct bio *bio)
                 down_read(&md->io_lock);
         }
 
-        __split_bio(md, bio);
+        r = __split_bio(md, bio);
         up_read(&md->io_lock);
+
+out_req:
+        if (r < 0)
+                bio_io_error(bio);
+
         return 0;
 }
 
@@ -977,6 +988,9 @@ static struct mapped_device *alloc_dev(int minor)
         atomic_set(&md->holders, 1);
         atomic_set(&md->open_count, 0);
         atomic_set(&md->event_nr, 0);
+        atomic_set(&md->uevent_seq, 0);
+        INIT_LIST_HEAD(&md->uevent_list);
+        spin_lock_init(&md->uevent_lock);
 
         md->queue = blk_alloc_queue(GFP_KERNEL);
         if (!md->queue)
@@ -1044,12 +1058,14 @@ static struct mapped_device *alloc_dev(int minor)
         return NULL;
 }
 
+static void unlock_fs(struct mapped_device *md);
+
 static void free_dev(struct mapped_device *md)
 {
         int minor = md->disk->first_minor;
 
         if (md->suspended_bdev) {
-                thaw_bdev(md->suspended_bdev, NULL);
+                unlock_fs(md);
                 bdput(md->suspended_bdev);
         }
         mempool_destroy(md->tio_pool);
@@ -1073,8 +1089,16 @@ static void free_dev(struct mapped_device *md)
  */
 static void event_callback(void *context)
 {
+        unsigned long flags;
+        LIST_HEAD(uevents);
         struct mapped_device *md = (struct mapped_device *) context;
 
+        spin_lock_irqsave(&md->uevent_lock, flags);
+        list_splice_init(&md->uevent_list, &uevents);
+        spin_unlock_irqrestore(&md->uevent_lock, flags);
+
+        dm_send_uevents(&uevents, &md->disk->kobj);
+
         atomic_inc(&md->event_nr);
         wake_up(&md->eventq);
 }
@@ -1233,7 +1257,8 @@ static void __flush_deferred_io(struct mapped_device *md, struct bio *c)
         while (c) {
                 n = c->bi_next;
                 c->bi_next = NULL;
-                __split_bio(md, c);
+                if (__split_bio(md, c))
+                        bio_io_error(c);
                 c = n;
         }
 }
@@ -1491,6 +1516,11 @@ out:
 /*-----------------------------------------------------------------
  * Event notification.
  *---------------------------------------------------------------*/
+uint32_t dm_next_uevent_seq(struct mapped_device *md)
+{
+        return atomic_add_return(1, &md->uevent_seq);
+}
+
 uint32_t dm_get_event_nr(struct mapped_device *md)
 {
         return atomic_read(&md->event_nr);
@@ -1502,6 +1532,15 @@ int dm_wait_event(struct mapped_device *md, int event_nr)
                         (event_nr != atomic_read(&md->event_nr)));
 }
 
+void dm_uevent_add(struct mapped_device *md, struct list_head *elist)
+{
+        unsigned long flags;
+
+        spin_lock_irqsave(&md->uevent_lock, flags);
+        list_add(elist, &md->uevent_list);
+        spin_unlock_irqrestore(&md->uevent_lock, flags);
+}
+
 /*
  * The gendisk is only valid as long as you have a reference
  * count on 'md'.
diff --git a/drivers/md/kcopyd.c b/drivers/md/kcopyd.c
index 7e052378c47e..f3831f31223e 100644
--- a/drivers/md/kcopyd.c
+++ b/drivers/md/kcopyd.c
@@ -198,7 +198,7 @@ struct kcopyd_job {
          * These fields are only used if the job has been split
          * into more manageable parts.
          */
-        struct semaphore lock;
+        struct mutex lock;
         atomic_t sub_jobs;
         sector_t progress;
 };
@@ -456,7 +456,7 @@ static void segment_complete(int read_err,
         sector_t count = 0;
         struct kcopyd_job *job = (struct kcopyd_job *) context;
 
-        down(&job->lock);
+        mutex_lock(&job->lock);
 
         /* update the error */
         if (read_err)
@@ -480,7 +480,7 @@ static void segment_complete(int read_err,
                         job->progress += count;
                 }
         }
-        up(&job->lock);
+        mutex_unlock(&job->lock);
 
         if (count) {
                 int i;
@@ -562,7 +562,7 @@ int kcopyd_copy(struct kcopyd_client *kc, struct io_region *from,
                 dispatch_job(job);
 
         else {
-                init_MUTEX(&job->lock);
+                mutex_init(&job->lock);
                 job->progress = 0;
                 split_job(job);
         }
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 16775a0df7f6..85478d6a9c1a 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -9,7 +9,7 @@
  *
  * Better read-balancing code written by Mika Kuoppala <miku@iki.fi>, 2000
  *
- * Fixes to reconstruction by Jakob Østergaard" <jakob@ostenfeld.dk>
+ * Fixes to reconstruction by Jakob Østergaard" <jakob@ostenfeld.dk>
  * Various fixes by Neil Brown <neilb@cse.unsw.edu.au>
  *
  * Changes by Peter T. Breuer <ptb@it.uc3m.es> 31/1/2003 to support