Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6

[pandora-kernel.git] / drivers / md / dm-mpath.c

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 217615b..d754e0b 100644 (file)
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -114,12 +114,10 @@ static void trigger_event(void *data);
 
 static struct pgpath *alloc_pgpath(void)
 {
-       struct pgpath *pgpath = kmalloc(sizeof(*pgpath), GFP_KERNEL);
+       struct pgpath *pgpath = kzalloc(sizeof(*pgpath), GFP_KERNEL);
 
-       if (pgpath) {
-               memset(pgpath, 0, sizeof(*pgpath));
+       if (pgpath)
                pgpath->path.is_active = 1;
-       }
 
        return pgpath;
 }
@@ -133,12 +131,10 @@ static struct priority_group *alloc_priority_group(void)
 {
        struct priority_group *pg;
 
-       pg = kmalloc(sizeof(*pg), GFP_KERNEL);
-       if (!pg)
-               return NULL;
+       pg = kzalloc(sizeof(*pg), GFP_KERNEL);
 
-       memset(pg, 0, sizeof(*pg));
-       INIT_LIST_HEAD(&pg->pgpaths);
+       if (pg)
+               INIT_LIST_HEAD(&pg->pgpaths);
 
        return pg;
 }
@@ -168,13 +164,12 @@ static void free_priority_group(struct priority_group *pg,
        kfree(pg);
 }
 
-static struct multipath *alloc_multipath(void)
+static struct multipath *alloc_multipath(struct dm_target *ti)
 {
        struct multipath *m;
 
-       m = kmalloc(sizeof(*m), GFP_KERNEL);
+       m = kzalloc(sizeof(*m), GFP_KERNEL);
        if (m) {
-               memset(m, 0, sizeof(*m));
                INIT_LIST_HEAD(&m->priority_groups);
                spin_lock_init(&m->lock);
                m->queue_io = 1;
@@ -185,6 +180,8 @@ static struct multipath *alloc_multipath(void)
                        kfree(m);
                        return NULL;
                }
+               m->ti = ti;
+               ti->private = m;
        }
 
        return m;
@@ -557,8 +554,7 @@ static struct pgpath *parse_path(struct arg_set *as, struct path_selector *ps,
 }
 
 static struct priority_group *parse_priority_group(struct arg_set *as,
-                                                  struct multipath *m,
-                                                  struct dm_target *ti)
+                                                  struct multipath *m)
 {
        static struct param _params[] = {
                {1, 1024, "invalid number of paths"},
@@ -568,6 +564,7 @@ static struct priority_group *parse_priority_group(struct arg_set *as,
        int r;
        unsigned i, nr_selector_args, nr_params;
        struct priority_group *pg;
+       struct dm_target *ti = m->ti;
 
        if (as->argc < 2) {
                as->argc = 0;
@@ -624,12 +621,12 @@ static struct priority_group *parse_priority_group(struct arg_set *as,
        return NULL;
 }
 
-static int parse_hw_handler(struct arg_set *as, struct multipath *m,
-                           struct dm_target *ti)
+static int parse_hw_handler(struct arg_set *as, struct multipath *m)
 {
        int r;
        struct hw_handler_type *hwht;
        unsigned hw_argc;
+       struct dm_target *ti = m->ti;
 
        static struct param _params[] = {
                {0, 1024, "invalid number of hardware handler args"},
@@ -661,11 +658,11 @@ static int parse_hw_handler(struct arg_set *as, struct multipath *m,
        return 0;
 }
 
-static int parse_features(struct arg_set *as, struct multipath *m,
-                         struct dm_target *ti)
+static int parse_features(struct arg_set *as, struct multipath *m)
 {
        int r;
        unsigned argc;
+       struct dm_target *ti = m->ti;
 
        static struct param _params[] = {
                {0, 1, "invalid number of feature args"},
@@ -704,17 +701,17 @@ static int multipath_ctr(struct dm_target *ti, unsigned int argc,
        as.argc = argc;
        as.argv = argv;
 
-       m = alloc_multipath();
+       m = alloc_multipath(ti);
        if (!m) {
                ti->error = "can't allocate multipath";
                return -EINVAL;
        }
 
-       r = parse_features(&as, m, ti);
+       r = parse_features(&as, m);
        if (r)
                goto bad;
 
-       r = parse_hw_handler(&as, m, ti);
+       r = parse_hw_handler(&as, m);
        if (r)
                goto bad;
 
@@ -730,7 +727,7 @@ static int multipath_ctr(struct dm_target *ti, unsigned int argc,
        while (as.argc) {
                struct priority_group *pg;
 
-               pg = parse_priority_group(&as, m, ti);
+               pg = parse_priority_group(&as, m);
                if (!pg) {
                        r = -EINVAL;
                        goto bad;
@@ -750,9 +747,6 @@ static int multipath_ctr(struct dm_target *ti, unsigned int argc,
                goto bad;
        }
 
-       ti->private = m;
-       m->ti = ti;
-
        return 0;
 
  bad:
@@ -1265,12 +1259,47 @@ error:
        return -EINVAL;
 }
 
+static int multipath_ioctl(struct dm_target *ti, struct inode *inode,
+                          struct file *filp, unsigned int cmd,
+                          unsigned long arg)
+{
+       struct multipath *m = (struct multipath *) ti->private;
+       struct block_device *bdev = NULL;
+       unsigned long flags;
+       struct file fake_file = {};
+       struct dentry fake_dentry = {};
+       int r = 0;
+
+       fake_file.f_dentry = &fake_dentry;
+
+       spin_lock_irqsave(&m->lock, flags);
+
+       if (!m->current_pgpath)
+               __choose_pgpath(m);
+
+       if (m->current_pgpath) {
+               bdev = m->current_pgpath->path.dev->bdev;
+               fake_dentry.d_inode = bdev->bd_inode;
+               fake_file.f_mode = m->current_pgpath->path.dev->mode;
+       }
+
+       if (m->queue_io)
+               r = -EAGAIN;
+       else if (!bdev)
+               r = -EIO;
+
+       spin_unlock_irqrestore(&m->lock, flags);
+
+       return r ? : blkdev_driver_ioctl(bdev->bd_inode, &fake_file,
+                                        bdev->bd_disk, cmd, arg);
+}
+
 /*-----------------------------------------------------------------
  * Module setup
  *---------------------------------------------------------------*/
 static struct target_type multipath_target = {
        .name = "multipath",
-       .version = {1, 0, 4},
+       .version = {1, 0, 5},
        .module = THIS_MODULE,
        .ctr = multipath_ctr,
        .dtr = multipath_dtr,
@@ -1280,6 +1309,7 @@ static struct target_type multipath_target = {
        .resume = multipath_resume,
        .status = multipath_status,
        .message = multipath_message,
+       .ioctl  = multipath_ioctl,
 };
 
 static int __init dm_multipath_init(void)