md: improve partition detection in md array

[linux-2.6-block.git] / drivers / md / md.c

diff --git a/drivers/md/md.c b/drivers/md/md.c
index bad324171cad49dc1b247199f88bca6537d1de69..2901d0c0ee9ec4f166e8a6b5c8a080449e571c20 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -274,6 +274,7 @@ static mddev_t * mddev_find(dev_t unit)
        atomic_set(&new->active, 1);
        spin_lock_init(&new->write_lock);
        init_waitqueue_head(&new->sb_wait);
+       new->reshape_position = MaxSector;
 
        new->queue = blk_alloc_queue(GFP_KERNEL);
        if (!new->queue) {
@@ -2242,6 +2243,10 @@ static ssize_t
 layout_show(mddev_t *mddev, char *page)
 {
        /* just a number, not meaningful for all levels */
+       if (mddev->reshape_position != MaxSector &&
+           mddev->layout != mddev->new_layout)
+               return sprintf(page, "%d (%d)\n",
+                              mddev->new_layout, mddev->layout);
        return sprintf(page, "%d\n", mddev->layout);
 }
 
@@ -2250,13 +2255,16 @@ layout_store(mddev_t *mddev, const char *buf, size_t len)
 {
        char *e;
        unsigned long n = simple_strtoul(buf, &e, 10);
-       if (mddev->pers)
-               return -EBUSY;
 
        if (!*buf || (*e && *e != '\n'))
                return -EINVAL;
 
-       mddev->layout = n;
+       if (mddev->pers)
+               return -EBUSY;
+       if (mddev->reshape_position != MaxSector)
+               mddev->new_layout = n;
+       else
+               mddev->layout = n;
        return len;
 }
 static struct md_sysfs_entry md_layout =
@@ -2268,6 +2276,10 @@ raid_disks_show(mddev_t *mddev, char *page)
 {
        if (mddev->raid_disks == 0)
                return 0;
+       if (mddev->reshape_position != MaxSector &&
+           mddev->delta_disks != 0)
+               return sprintf(page, "%d (%d)\n", mddev->raid_disks,
+                              mddev->raid_disks - mddev->delta_disks);
        return sprintf(page, "%d\n", mddev->raid_disks);
 }
 
@@ -2285,7 +2297,11 @@ raid_disks_store(mddev_t *mddev, const char *buf, size_t len)
 
        if (mddev->pers)
                rv = update_raid_disks(mddev, n);
-       else
+       else if (mddev->reshape_position != MaxSector) {
+               int olddisks = mddev->raid_disks - mddev->delta_disks;
+               mddev->delta_disks = n - olddisks;
+               mddev->raid_disks = n;
+       } else
                mddev->raid_disks = n;
        return rv ? rv : len;
 }
@@ -2295,6 +2311,10 @@ __ATTR(raid_disks, S_IRUGO|S_IWUSR, raid_disks_show, raid_disks_store);
 static ssize_t
 chunk_size_show(mddev_t *mddev, char *page)
 {
+       if (mddev->reshape_position != MaxSector &&
+           mddev->chunk_size != mddev->new_chunk)
+               return sprintf(page, "%d (%d)\n", mddev->new_chunk,
+                              mddev->chunk_size);
        return sprintf(page, "%d\n", mddev->chunk_size);
 }
 
@@ -2305,12 +2325,15 @@ chunk_size_store(mddev_t *mddev, const char *buf, size_t len)
        char *e;
        unsigned long n = simple_strtoul(buf, &e, 10);
 
-       if (mddev->pers)
-               return -EBUSY;
        if (!*buf || (*e && *e != '\n'))
                return -EINVAL;
 
-       mddev->chunk_size = n;
+       if (mddev->pers)
+               return -EBUSY;
+       else if (mddev->reshape_position != MaxSector)
+               mddev->new_chunk = n;
+       else
+               mddev->chunk_size = n;
        return len;
 }
 static struct md_sysfs_entry md_chunk_size =
@@ -2896,6 +2919,37 @@ suspend_hi_store(mddev_t *mddev, const char *buf, size_t len)
 static struct md_sysfs_entry md_suspend_hi =
 __ATTR(suspend_hi, S_IRUGO|S_IWUSR, suspend_hi_show, suspend_hi_store);
 
+static ssize_t
+reshape_position_show(mddev_t *mddev, char *page)
+{
+       if (mddev->reshape_position != MaxSector)
+               return sprintf(page, "%llu\n",
+                              (unsigned long long)mddev->reshape_position);
+       strcpy(page, "none\n");
+       return 5;
+}
+
+static ssize_t
+reshape_position_store(mddev_t *mddev, const char *buf, size_t len)
+{
+       char *e;
+       unsigned long long new = simple_strtoull(buf, &e, 10);
+       if (mddev->pers)
+               return -EBUSY;
+       if (buf == e || (*e && *e != '\n'))
+               return -EINVAL;
+       mddev->reshape_position = new;
+       mddev->delta_disks = 0;
+       mddev->new_level = mddev->level;
+       mddev->new_layout = mddev->layout;
+       mddev->new_chunk = mddev->chunk_size;
+       return len;
+}
+
+static struct md_sysfs_entry md_reshape_position =
+__ATTR(reshape_position, S_IRUGO|S_IWUSR, reshape_position_show,
+       reshape_position_store);
+
 
 static struct attribute *md_default_attrs[] = {
        &md_level.attr,
@@ -2908,6 +2962,7 @@ static struct attribute *md_default_attrs[] = {
        &md_new_device.attr,
        &md_safe_delay.attr,
        &md_array_state.attr,
+       &md_reshape_position.attr,
        NULL,
 };
 
@@ -3049,6 +3104,7 @@ static int do_md_run(mddev_t * mddev)
        struct gendisk *disk;
        struct mdk_personality *pers;
        char b[BDEVNAME_SIZE];
+       struct block_device *bdev;
 
        if (list_empty(&mddev->disks))
                /* cannot run an array with no devices.. */
@@ -3276,7 +3332,13 @@ static int do_md_run(mddev_t * mddev)
        md_wakeup_thread(mddev->thread);
        md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
 
-       mddev->changed = 1;
+       bdev = bdget_disk(mddev->gendisk, 0);
+       if (bdev) {
+               bd_set_size(bdev, mddev->array_size << 1);
+               blkdev_ioctl(bdev->bd_inode, NULL, BLKRRPART, 0);
+               bdput(bdev);
+       }
+
        md_new_event(mddev);
        kobject_uevent(&mddev->gendisk->kobj, KOBJ_CHANGE);
        return 0;
@@ -3398,7 +3460,6 @@ static int do_md_stop(mddev_t * mddev, int mode)
                        mddev->pers = NULL;
 
                        set_capacity(disk, 0);
-                       mddev->changed = 1;
 
                        if (mddev->ro)
                                mddev->ro = 0;
@@ -3446,6 +3507,7 @@ static int do_md_stop(mddev_t * mddev, int mode)
                mddev->size = 0;
                mddev->raid_disks = 0;
                mddev->recovery_cp = 0;
+               mddev->reshape_position = MaxSector;
 
        } else if (mddev->pers)
                printk(KERN_INFO "md: %s switched to read-only mode.\n",
@@ -4537,20 +4599,6 @@ static int md_release(struct inode *inode, struct file * file)
        return 0;
 }
 
-static int md_media_changed(struct gendisk *disk)
-{
-       mddev_t *mddev = disk->private_data;
-
-       return mddev->changed;
-}
-
-static int md_revalidate(struct gendisk *disk)
-{
-       mddev_t *mddev = disk->private_data;
-
-       mddev->changed = 0;
-       return 0;
-}
 static struct block_device_operations md_fops =
 {
        .owner          = THIS_MODULE,
@@ -4558,8 +4606,6 @@ static struct block_device_operations md_fops =
        .release        = md_release,
        .ioctl          = md_ioctl,
        .getgeo         = md_getgeo,
-       .media_changed  = md_media_changed,
-       .revalidate_disk= md_revalidate,
 };
 
 static int md_thread(void * arg)