- Update to 3.4-rc7.
[linux-flexiantxendom0-3.2.10.git] / drivers / md / dm-mpath.c
index 52f0de3..6195bff 100644 (file)
 #include <linux/time.h>
 #include <linux/workqueue.h>
 #include <scsi/scsi_dh.h>
-#include <asm/atomic.h>
+#include <linux/atomic.h>
 
 #define DM_MSG_PREFIX "multipath"
-#define MESG_STR(x) x, sizeof(x)
 #define DM_PG_INIT_DELAY_MSECS 2000
 #define DM_PG_INIT_DELAY_DEFAULT ((unsigned) -1)
 
@@ -57,6 +56,8 @@ struct priority_group {
        struct list_head pgpaths;
 };
 
+#define FEATURE_NO_PARTITIONS 1
+
 /* Multipath context */
 struct multipath {
        struct list_head list;
@@ -88,6 +89,7 @@ struct multipath {
        unsigned pg_init_retries;       /* Number of times to retry pg_init */
        unsigned pg_init_count;         /* Number of times pg_init called */
        unsigned pg_init_delay_msecs;   /* Number of msecs before pg_init retry */
+       unsigned features;              /* Additional selected features */
 
        struct work_struct process_queued_ios;
        struct list_head queued_ios;
@@ -160,12 +162,9 @@ static struct priority_group *alloc_priority_group(void)
 static void free_pgpaths(struct list_head *pgpaths, struct dm_target *ti)
 {
        struct pgpath *pgpath, *tmp;
-       struct multipath *m = ti->private;
 
        list_for_each_entry_safe(pgpath, tmp, pgpaths, list) {
                list_del(&pgpath->list);
-               if (m->hw_handler_name)
-                       scsi_dh_detach(bdev_get_queue(pgpath->path.dev->bdev));
                dm_put_device(ti, pgpath->path.dev);
                free_pgpath(pgpath);
        }
@@ -227,6 +226,27 @@ static void free_multipath(struct multipath *m)
        kfree(m);
 }
 
+static int set_mapinfo(struct multipath *m, union map_info *info)
+{
+       struct dm_mpath_io *mpio;
+
+       mpio = mempool_alloc(m->mpio_pool, GFP_ATOMIC);
+       if (!mpio)
+               return -ENOMEM;
+
+       memset(mpio, 0, sizeof(*mpio));
+       info->ptr = mpio;
+
+       return 0;
+}
+
+static void clear_mapinfo(struct multipath *m, union map_info *info)
+{
+       struct dm_mpath_io *mpio = info->ptr;
+
+       info->ptr = NULL;
+       mempool_free(mpio, m->mpio_pool);
+}
 
 /*-----------------------------------------------
  * Path selection
@@ -279,6 +299,11 @@ static int __choose_path_in_pg(struct multipath *m, struct priority_group *pg,
 
        m->current_pgpath = path_to_pgpath(path);
 
+       if (!m->current_pgpath->path.dev) {
+               m->current_pgpath = NULL;
+               return -ENODEV;
+       }
+
        if (m->current_pg != pg)
                __switch_pg(m, m->current_pgpath);
 
@@ -342,13 +367,14 @@ static int __must_push_back(struct multipath *m)
 }
 
 static int map_io(struct multipath *m, struct request *clone,
-                 struct dm_mpath_io *mpio, unsigned was_queued)
+                 union map_info *map_context, unsigned was_queued)
 {
        int r = DM_MAPIO_REMAPPED;
        size_t nr_bytes = blk_rq_bytes(clone);
        unsigned long flags;
        struct pgpath *pgpath;
        struct block_device *bdev;
+       struct dm_mpath_io *mpio = map_context->ptr;
 
        spin_lock_irqsave(&m->lock, flags);
 
@@ -424,7 +450,6 @@ static void dispatch_queued_ios(struct multipath *m)
 {
        int r;
        unsigned long flags;
-       struct dm_mpath_io *mpio;
        union map_info *info;
        struct request *clone, *n;
        LIST_HEAD(cl);
@@ -437,16 +462,15 @@ static void dispatch_queued_ios(struct multipath *m)
                list_del_init(&clone->queuelist);
 
                info = dm_get_rq_mapinfo(clone);
-               mpio = info->ptr;
 
-               r = map_io(m, clone, mpio, 1);
+               r = map_io(m, clone, info, 1);
                if (r < 0) {
-                       mempool_free(mpio, m->mpio_pool);
+                       clear_mapinfo(m, info);
                        dm_kill_unmapped_request(clone, r);
                } else if (r == DM_MAPIO_REMAPPED)
                        dm_dispatch_request(clone);
                else if (r == DM_MAPIO_REQUEUE) {
-                       mempool_free(mpio, m->mpio_pool);
+                       clear_mapinfo(m, info);
                        dm_requeue_unmapped_request(clone);
                }
        }
@@ -505,80 +529,29 @@ static void trigger_event(struct work_struct *work)
  *      <#paths> <#per-path selector args>
  *         [<path> [<arg>]* ]+ ]+
  *---------------------------------------------------------------*/
-struct param {
-       unsigned min;
-       unsigned max;
-       char *error;
-};
-
-static int read_param(struct param *param, char *str, unsigned *v, char **error)
-{
-       if (!str ||
-           (sscanf(str, "%u", v) != 1) ||
-           (*v < param->min) ||
-           (*v > param->max)) {
-               *error = param->error;
-               return -EINVAL;
-       }
-
-       return 0;
-}
-
-struct arg_set {
-       unsigned argc;
-       char **argv;
-};
-
-static char *shift(struct arg_set *as)
-{
-       char *r;
-
-       if (as->argc) {
-               as->argc--;
-               r = *as->argv;
-               as->argv++;
-               return r;
-       }
-
-       return NULL;
-}
-
-static void consume(struct arg_set *as, unsigned n)
-{
-       BUG_ON (as->argc < n);
-       as->argc -= n;
-       as->argv += n;
-}
-
-static int parse_path_selector(struct arg_set *as, struct priority_group *pg,
+static int parse_path_selector(struct dm_arg_set *as, struct priority_group *pg,
                               struct dm_target *ti)
 {
        int r;
        struct path_selector_type *pst;
        unsigned ps_argc;
 
-       static struct param _params[] = {
+       static struct dm_arg _args[] = {
                {0, 1024, "invalid number of path selector args"},
        };
 
-       pst = dm_get_path_selector(shift(as));
+       pst = dm_get_path_selector(dm_shift_arg(as));
        if (!pst) {
                ti->error = "unknown path selector type";
                return -EINVAL;
        }
 
-       r = read_param(_params, shift(as), &ps_argc, &ti->error);
+       r = dm_read_arg_group(_args, as, &ps_argc, &ti->error);
        if (r) {
                dm_put_path_selector(pst);
                return -EINVAL;
        }
 
-       if (ps_argc > as->argc) {
-               dm_put_path_selector(pst);
-               ti->error = "not enough arguments for path selector";
-               return -EINVAL;
-       }
-
        r = pst->create(&pg->ps, ps_argc, as->argv);
        if (r) {
                dm_put_path_selector(pst);
@@ -587,16 +560,17 @@ static int parse_path_selector(struct arg_set *as, struct priority_group *pg,
        }
 
        pg->ps.type = pst;
-       consume(as, ps_argc);
+       dm_consume_args(as, ps_argc);
 
        return 0;
 }
 
-static struct pgpath *parse_path(struct arg_set *as, struct path_selector *ps,
+static struct pgpath *parse_path(struct dm_arg_set *as, struct path_selector *ps,
                               struct dm_target *ti)
 {
        int r;
        struct pgpath *p;
+       char *path;
        struct multipath *m = ti->private;
 
        /* we need at least a path arg */
@@ -609,30 +583,57 @@ static struct pgpath *parse_path(struct arg_set *as, struct path_selector *ps,
        if (!p)
                return ERR_PTR(-ENOMEM);
 
-       r = dm_get_device(ti, shift(as), dm_table_get_mode(ti->table),
+       path = dm_shift_arg(as);
+       r = dm_get_device(ti, path, dm_table_get_mode(ti->table),
                          &p->path.dev);
        if (r) {
-               ti->error = "error getting device";
-               goto bad;
+               unsigned major, minor;
+
+               /* Try to add a failed device */
+               if (r == -ENXIO && sscanf(path, "%u:%u", &major, &minor) == 2) {
+                       dev_t dev;
+
+                       /* Extract the major/minor numbers */
+                       dev = MKDEV(major, minor);
+                       if (MAJOR(dev) != major || MINOR(dev) != minor) {
+                               /* Nice try, didn't work */
+                               DMWARN("Invalid device path %s", path);
+                               ti->error = "error converting devnum";
+                               goto bad;
+                       }
+                       DMWARN("adding disabled device %d:%d", major, minor);
+                       p->path.dev = NULL;
+                       format_dev_t(p->path.pdev, dev);
+                       p->is_active = 0;
+               } else {
+                       ti->error = "error getting device";
+                       goto bad;
+               }
+       } else {
+               memcpy(p->path.pdev, p->path.dev->name, 16);
        }
 
-       if (m->hw_handler_name) {
+       if (p->path.dev) {
                struct request_queue *q = bdev_get_queue(p->path.dev->bdev);
 
-               r = scsi_dh_attach(q, m->hw_handler_name);
-               if (r == -EBUSY) {
-                       /*
-                        * Already attached to different hw_handler,
-                        * try to reattach with correct one.
-                        */
-                       scsi_dh_detach(q);
+               if (m->hw_handler_name) {
                        r = scsi_dh_attach(q, m->hw_handler_name);
-               }
-
-               if (r < 0) {
-                       ti->error = "error attaching hardware handler";
-                       dm_put_device(ti, p->path.dev);
-                       goto bad;
+                       if (r == -EBUSY) {
+                               /*
+                                * Already attached to different hw_handler,
+                                * try to reattach with correct one.
+                                */
+                               scsi_dh_detach(q);
+                               r = scsi_dh_attach(q, m->hw_handler_name);
+                       }
+                       if (r < 0) {
+                               ti->error = "error attaching hardware handler";
+                               dm_put_device(ti, p->path.dev);
+                               goto bad;
+                       }
+               } else {
+                       /* Play safe and detach hardware handler */
+                       scsi_dh_detach(q);
                }
 
                if (m->hw_handler_params) {
@@ -653,6 +654,11 @@ static struct pgpath *parse_path(struct arg_set *as, struct path_selector *ps,
                goto bad;
        }
 
+       if (!p->is_active) {
+               ps->type->fail_path(ps, &p->path);
+               p->fail_count++;
+               m->nr_valid_paths--;
+       }
        return p;
 
  bad:
@@ -660,16 +666,16 @@ static struct pgpath *parse_path(struct arg_set *as, struct path_selector *ps,
        return ERR_PTR(r);
 }
 
-static struct priority_group *parse_priority_group(struct arg_set *as,
+static struct priority_group *parse_priority_group(struct dm_arg_set *as,
                                                   struct multipath *m)
 {
-       static struct param _params[] = {
+       static struct dm_arg _args[] = {
                {1, 1024, "invalid number of paths"},
                {0, 1024, "invalid number of selector args"}
        };
 
        int r;
-       unsigned i, nr_selector_args, nr_params;
+       unsigned i, nr_selector_args, nr_args;
        struct priority_group *pg;
        struct dm_target *ti = m->ti;
 
@@ -693,26 +699,26 @@ static struct priority_group *parse_priority_group(struct arg_set *as,
        /*
         * read the paths
         */
-       r = read_param(_params, shift(as), &pg->nr_pgpaths, &ti->error);
+       r = dm_read_arg(_args, as, &pg->nr_pgpaths, &ti->error);
        if (r)
                goto bad;
 
-       r = read_param(_params + 1, shift(as), &nr_selector_args, &ti->error);
+       r = dm_read_arg(_args + 1, as, &nr_selector_args, &ti->error);
        if (r)
                goto bad;
 
-       nr_params = 1 + nr_selector_args;
+       nr_args = 1 + nr_selector_args;
        for (i = 0; i < pg->nr_pgpaths; i++) {
                struct pgpath *pgpath;
-               struct arg_set path_args;
+               struct dm_arg_set path_args;
 
-               if (as->argc < nr_params) {
+               if (as->argc < nr_args) {
                        ti->error = "not enough path parameters";
                        r = -EINVAL;
                        goto bad;
                }
 
-               path_args.argc = nr_params;
+               path_args.argc = nr_args;
                path_args.argv = as->argv;
 
                pgpath = parse_path(&path_args, &pg->ps, ti);
@@ -723,7 +729,7 @@ static struct priority_group *parse_priority_group(struct arg_set *as,
 
                pgpath->pg = pg;
                list_add_tail(&pgpath->list, &pg->pgpaths);
-               consume(as, nr_params);
+               dm_consume_args(as, nr_args);
        }
 
        return pg;
@@ -733,30 +739,25 @@ static struct priority_group *parse_priority_group(struct arg_set *as,
        return ERR_PTR(r);
 }
 
-static int parse_hw_handler(struct arg_set *as, struct multipath *m)
+static int parse_hw_handler(struct dm_arg_set *as, struct multipath *m)
 {
        unsigned hw_argc;
        int ret;
        struct dm_target *ti = m->ti;
 
-       static struct param _params[] = {
+       static struct dm_arg _args[] = {
                {0, 1024, "invalid number of hardware handler args"},
        };
 
-       if (read_param(_params, shift(as), &hw_argc, &ti->error))
+       if (dm_read_arg_group(_args, as, &hw_argc, &ti->error))
                return -EINVAL;
 
        if (!hw_argc)
                return 0;
 
-       if (hw_argc > as->argc) {
-               ti->error = "not enough arguments for hardware handler";
-               return -EINVAL;
-       }
-
-       m->hw_handler_name = kstrdup(shift(as), GFP_KERNEL);
-       request_module("scsi_dh_%s", m->hw_handler_name);
-       if (scsi_dh_handler_exist(m->hw_handler_name) == 0) {
+       m->hw_handler_name = kstrdup(dm_shift_arg(as), GFP_KERNEL);
+       if (!try_then_request_module(scsi_dh_handler_exist(m->hw_handler_name),
+                                    "scsi_dh_%s", m->hw_handler_name)) {
                ti->error = "unknown hardware handler type";
                ret = -EINVAL;
                goto fail;
@@ -778,7 +779,7 @@ static int parse_hw_handler(struct arg_set *as, struct multipath *m)
                for (i = 0, p+=j+1; i <= hw_argc - 2; i++, p+=j+1)
                        j = sprintf(p, "%s", as->argv[i]);
        }
-       consume(as, hw_argc - 1);
+       dm_consume_args(as, hw_argc - 1);
 
        return 0;
 fail:
@@ -787,20 +788,20 @@ fail:
        return ret;
 }
 
-static int parse_features(struct arg_set *as, struct multipath *m)
+static int parse_features(struct dm_arg_set *as, struct multipath *m)
 {
        int r;
        unsigned argc;
        struct dm_target *ti = m->ti;
-       const char *param_name;
+       const char *arg_name;
 
-       static struct param _params[] = {
+       static struct dm_arg _args[] = {
                {0, 5, "invalid number of feature args"},
                {1, 50, "pg_init_retries must be between 1 and 50"},
                {0, 60000, "pg_init_delay_msecs must be between 0 and 60000"},
        };
 
-       r = read_param(_params, shift(as), &argc, &ti->error);
+       r = dm_read_arg_group(_args, as, &argc, &ti->error);
        if (r)
                return -EINVAL;
 
@@ -808,26 +809,28 @@ static int parse_features(struct arg_set *as, struct multipath *m)
                return 0;
 
        do {
-               param_name = shift(as);
+               arg_name = dm_shift_arg(as);
                argc--;
 
-               if (!strnicmp(param_name, MESG_STR("queue_if_no_path"))) {
+               if (!strcasecmp(arg_name, "queue_if_no_path")) {
                        r = queue_if_no_path(m, 1, 0);
                        continue;
                }
 
-               if (!strnicmp(param_name, MESG_STR("pg_init_retries")) &&
+               if (!strcasecmp(arg_name, "no_partitions")) {
+                       m->features |= FEATURE_NO_PARTITIONS;
+                       continue;
+               }
+               if (!strcasecmp(arg_name, "pg_init_retries") &&
                    (argc >= 1)) {
-                       r = read_param(_params + 1, shift(as),
-                                      &m->pg_init_retries, &ti->error);
+                       r = dm_read_arg(_args + 1, as, &m->pg_init_retries, &ti->error);
                        argc--;
                        continue;
                }
 
-               if (!strnicmp(param_name, MESG_STR("pg_init_delay_msecs")) &&
+               if (!strcasecmp(arg_name, "pg_init_delay_msecs") &&
                    (argc >= 1)) {
-                       r = read_param(_params + 2, shift(as),
-                                      &m->pg_init_delay_msecs, &ti->error);
+                       r = dm_read_arg(_args + 2, as, &m->pg_init_delay_msecs, &ti->error);
                        argc--;
                        continue;
                }
@@ -842,15 +845,15 @@ static int parse_features(struct arg_set *as, struct multipath *m)
 static int multipath_ctr(struct dm_target *ti, unsigned int argc,
                         char **argv)
 {
-       /* target parameters */
-       static struct param _params[] = {
-               {1, 1024, "invalid number of priority groups"},
-               {1, 1024, "invalid initial priority group number"},
+       /* target arguments */
+       static struct dm_arg _args[] = {
+               {0, 1024, "invalid number of priority groups"},
+               {0, 1024, "invalid initial priority group number"},
        };
 
        int r;
        struct multipath *m;
-       struct arg_set as;
+       struct dm_arg_set as;
        unsigned pg_count = 0;
        unsigned next_pg_num;
 
@@ -871,14 +874,21 @@ static int multipath_ctr(struct dm_target *ti, unsigned int argc,
        if (r)
                goto bad;
 
-       r = read_param(_params, shift(&as), &m->nr_priority_groups, &ti->error);
+       r = dm_read_arg(_args, &as, &m->nr_priority_groups, &ti->error);
        if (r)
                goto bad;
 
-       r = read_param(_params + 1, shift(&as), &next_pg_num, &ti->error);
+       r = dm_read_arg(_args + 1, &as, &next_pg_num, &ti->error);
        if (r)
                goto bad;
 
+       if ((!m->nr_priority_groups && next_pg_num) ||
+           (m->nr_priority_groups && !next_pg_num)) {
+               ti->error = "invalid initial priority group";
+               r = -EINVAL;
+               goto bad;
+       }
+
        /* parse the priority groups */
        while (as.argc) {
                struct priority_group *pg;
@@ -960,20 +970,16 @@ static int multipath_map(struct dm_target *ti, struct request *clone,
                         union map_info *map_context)
 {
        int r;
-       struct dm_mpath_io *mpio;
        struct multipath *m = (struct multipath *) ti->private;
 
-       mpio = mempool_alloc(m->mpio_pool, GFP_ATOMIC);
-       if (!mpio)
+       if (set_mapinfo(m, map_context) < 0)
                /* ENOMEM, requeue */
                return DM_MAPIO_REQUEUE;
-       memset(mpio, 0, sizeof(*mpio));
 
-       map_context->ptr = mpio;
        clone->cmd_flags |= REQ_FAILFAST_TRANSPORT;
-       r = map_io(m, clone, mpio, 0);
+       r = map_io(m, clone, map_context, 0);
        if (r < 0 || r == DM_MAPIO_REQUEUE)
-               mempool_free(mpio, m->mpio_pool);
+               clear_mapinfo(m, map_context);
 
        return r;
 }
@@ -991,7 +997,7 @@ static int fail_path(struct pgpath *pgpath)
        if (!pgpath->is_active)
                goto out;
 
-       DMWARN("Failing path %s.", pgpath->path.dev->name);
+       DMWARN("Failing path %s.", pgpath->path.pdev);
 
        pgpath->pg->ps.type->fail_path(&pgpath->pg->ps, &pgpath->path);
        pgpath->is_active = 0;
@@ -1003,7 +1009,7 @@ static int fail_path(struct pgpath *pgpath)
                m->current_pgpath = NULL;
 
        dm_path_uevent(DM_UEVENT_PATH_FAILED, m->ti,
-                     pgpath->path.dev->name, m->nr_valid_paths);
+                      pgpath->path.pdev, m->nr_valid_paths);
 
        schedule_work(&m->trigger_event);
 
@@ -1027,6 +1033,12 @@ static int reinstate_path(struct pgpath *pgpath)
        if (pgpath->is_active)
                goto out;
 
+       if (!pgpath->path.dev) {
+               DMWARN("Cannot reinstate disabled path %s", pgpath->path.pdev);
+               r = -ENODEV;
+               goto out;
+       }
+
        if (!pgpath->pg->ps.type->reinstate_path) {
                DMWARN("Reinstate path not supported by path selector %s",
                       pgpath->pg->ps.type->name);
@@ -1049,7 +1061,7 @@ static int reinstate_path(struct pgpath *pgpath)
        }
 
        dm_path_uevent(DM_UEVENT_PATH_REINSTATED, m->ti,
-                     pgpath->path.dev->name, m->nr_valid_paths);
+                      pgpath->path.pdev, m->nr_valid_paths);
 
        schedule_work(&m->trigger_event);
 
@@ -1069,6 +1081,9 @@ static int action_dev(struct multipath *m, struct dm_dev *dev,
        struct pgpath *pgpath;
        struct priority_group *pg;
 
+       if (!dev)
+               return 0;
+
        list_for_each_entry(pg, &m->priority_groups, list) {
                list_for_each_entry(pgpath, &pg->pgpaths, list) {
                        if (pgpath->path.dev == dev)
@@ -1106,8 +1121,9 @@ static int switch_pg_num(struct multipath *m, const char *pgstr)
        struct priority_group *pg;
        unsigned pgnum;
        unsigned long flags;
+       char dummy;
 
-       if (!pgstr || (sscanf(pgstr, "%u", &pgnum) != 1) || !pgnum ||
+       if (!pgstr || (sscanf(pgstr, "%u%c", &pgnum, &dummy) != 1) || !pgnum ||
            (pgnum > m->nr_priority_groups)) {
                DMWARN("invalid PG number supplied to switch_pg_num");
                return -EINVAL;
@@ -1137,8 +1153,9 @@ static int bypass_pg_num(struct multipath *m, const char *pgstr, int bypassed)
 {
        struct priority_group *pg;
        unsigned pgnum;
+       char dummy;
 
-       if (!pgstr || (sscanf(pgstr, "%u", &pgnum) != 1) || !pgnum ||
+       if (!pgstr || (sscanf(pgstr, "%u%c", &pgnum, &dummy) != 1) || !pgnum ||
            (pgnum > m->nr_priority_groups)) {
                DMWARN("invalid PG number supplied to bypass_pg");
                return -EINVAL;
@@ -1190,8 +1207,9 @@ static void pg_init_done(void *data, int errors)
                        errors = 0;
                        break;
                }
-               DMERR("Could not failover the device: Handler scsi_dh_%s "
-                     "Error %d.", m->hw_handler_name, errors);
+               DMERR("Count not failover device %s: Handler scsi_dh_%s "
+                     "was not loaded.", pgpath->path.dev->name,
+                     m->hw_handler_name);
                /*
                 * Fail path for now, so we do not ping pong
                 */
@@ -1204,6 +1222,10 @@ static void pg_init_done(void *data, int errors)
                 */
                bypass_pg(m, pg, 1);
                break;
+       case SCSI_DH_DEV_OFFLINED:
+               DMWARN("Device %s offlined.", pgpath->path.dev->name);
+               errors = 0;
+               break;
        case SCSI_DH_RETRY:
                /* Wait before retrying. */
                delay_retry = 1;
@@ -1225,7 +1247,8 @@ static void pg_init_done(void *data, int errors)
        spin_lock_irqsave(&m->lock, flags);
        if (errors) {
                if (pgpath == m->current_pgpath) {
-                       DMERR("Could not failover device. Error %d.", errors);
+                       DMERR("Could not failover device %s, error %d.",
+                             pgpath->path.dev->name, errors);
                        m->current_pgpath = NULL;
                        m->current_pg = NULL;
                }
@@ -1256,8 +1279,9 @@ static void activate_path(struct work_struct *work)
        struct pgpath *pgpath =
                container_of(work, struct pgpath, activate_path.work);
 
-       scsi_dh_activate(bdev_get_queue(pgpath->path.dev->bdev),
-                               pg_init_done, pgpath);
+       if (pgpath->path.dev)
+               scsi_dh_activate(bdev_get_queue(pgpath->path.dev->bdev),
+                                pg_init_done, pgpath);
 }
 
 /*
@@ -1283,7 +1307,7 @@ static int do_end_io(struct multipath *m, struct request *clone,
        if (!error && !clone->errors)
                return 0;       /* I/O complete */
 
-       if (error == -EOPNOTSUPP || error == -EREMOTEIO)
+       if (error == -EOPNOTSUPP || error == -EREMOTEIO || error == -EILSEQ)
                return error;
 
        if (mpio->pgpath)
@@ -1313,13 +1337,15 @@ static int multipath_end_io(struct dm_target *ti, struct request *clone,
        struct path_selector *ps;
        int r;
 
+       BUG_ON(!mpio);
+
        r  = do_end_io(m, clone, error, mpio);
        if (pgpath) {
                ps = &pgpath->pg->ps;
                if (ps->type->end_io)
                        ps->type->end_io(ps, &pgpath->path, mpio->nr_bytes);
        }
-       mempool_free(mpio, m->mpio_pool);
+       clear_mapinfo(m, map_context);
 
        return r;
 }
@@ -1394,11 +1420,14 @@ static int multipath_status(struct dm_target *ti, status_type_t type,
        else {
                DMEMIT("%u ", m->queue_if_no_path +
                              (m->pg_init_retries > 0) * 2 +
-                             (m->pg_init_delay_msecs != DM_PG_INIT_DELAY_DEFAULT) * 2);
+                             (m->pg_init_delay_msecs != DM_PG_INIT_DELAY_DEFAULT) * 2 +
+                             (m->features & FEATURE_NO_PARTITIONS));
                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 (m->features & FEATURE_NO_PARTITIONS)
+                       DMEMIT("no_partitions ");
                if (m->pg_init_delay_msecs != DM_PG_INIT_DELAY_DEFAULT)
                        DMEMIT("pg_init_delay_msecs %u ", m->pg_init_delay_msecs);
        }
@@ -1415,7 +1444,7 @@ static int multipath_status(struct dm_target *ti, status_type_t type,
        else if (m->current_pg)
                pg_num = m->current_pg->pg_num;
        else
-                       pg_num = 1;
+               pg_num = (m->nr_priority_groups ? 1 : 0);
 
        DMEMIT("%u ", pg_num);
 
@@ -1442,7 +1471,7 @@ static int multipath_status(struct dm_target *ti, status_type_t type,
                               pg->ps.type->info_args);
 
                        list_for_each_entry(p, &pg->pgpaths, list) {
-                               DMEMIT("%s %s %u ", p->path.dev->name,
+                               DMEMIT("%s %s %u ", p->path.pdev,
                                       p->is_active ? "A" : "F",
                                       p->fail_count);
                                if (pg->ps.type->status)
@@ -1468,7 +1497,7 @@ static int multipath_status(struct dm_target *ti, status_type_t type,
                               pg->ps.type->table_args);
 
                        list_for_each_entry(p, &pg->pgpaths, list) {
-                               DMEMIT("%s ", p->path.dev->name);
+                               DMEMIT("%s ", p->path.pdev);
                                if (pg->ps.type->status)
                                        sz += pg->ps.type->status(&pg->ps,
                                              &p->path, type, result + sz,
@@ -1498,10 +1527,10 @@ static int multipath_message(struct dm_target *ti, unsigned argc, char **argv)
        }
 
        if (argc == 1) {
-               if (!strnicmp(argv[0], MESG_STR("queue_if_no_path"))) {
+               if (!strcasecmp(argv[0], "queue_if_no_path")) {
                        r = queue_if_no_path(m, 1, 0);
                        goto out;
-               } else if (!strnicmp(argv[0], MESG_STR("fail_if_no_path"))) {
+               } else if (!strcasecmp(argv[0], "fail_if_no_path")) {
                        r = queue_if_no_path(m, 0, 0);
                        goto out;
                }
@@ -1512,18 +1541,18 @@ static int multipath_message(struct dm_target *ti, unsigned argc, char **argv)
                goto out;
        }
 
-       if (!strnicmp(argv[0], MESG_STR("disable_group"))) {
+       if (!strcasecmp(argv[0], "disable_group")) {
                r = bypass_pg_num(m, argv[1], 1);
                goto out;
-       } else if (!strnicmp(argv[0], MESG_STR("enable_group"))) {
+       } else if (!strcasecmp(argv[0], "enable_group")) {
                r = bypass_pg_num(m, argv[1], 0);
                goto out;
-       } else if (!strnicmp(argv[0], MESG_STR("switch_group"))) {
+       } else if (!strcasecmp(argv[0], "switch_group")) {
                r = switch_pg_num(m, argv[1]);
                goto out;
-       } else if (!strnicmp(argv[0], MESG_STR("reinstate_path")))
+       } else if (!strcasecmp(argv[0], "reinstate_path"))
                action = reinstate_path;
-       else if (!strnicmp(argv[0], MESG_STR("fail_path")))
+       else if (!strcasecmp(argv[0], "fail_path"))
                action = fail_path;
        else {
                DMWARN("Unrecognised multipath message received.");
@@ -1560,7 +1589,7 @@ static int multipath_ioctl(struct dm_target *ti, unsigned int cmd,
        if (!m->current_pgpath)
                __choose_pgpath(m, 0);
 
-       if (m->current_pgpath) {
+       if (m->current_pgpath && m->current_pgpath->path.dev) {
                bdev = m->current_pgpath->path.dev->bdev;
                mode = m->current_pgpath->path.dev->mode;
        }
@@ -1572,6 +1601,12 @@ static int multipath_ioctl(struct dm_target *ti, unsigned int cmd,
 
        spin_unlock_irqrestore(&m->lock, flags);
 
+       /*
+        * Only pass ioctls through if the device sizes match exactly.
+        */
+       if (!r && ti->len != i_size_read(bdev->bd_inode) >> SECTOR_SHIFT)
+               r = scsi_verify_blk_ioctl(NULL, cmd);
+
        return r ? : __blkdev_driver_ioctl(bdev, mode, cmd, arg);
 }