md: allow a maximum extent to be set for resyncing

[linux-2.6-omap-h63xx.git] / drivers / md / md.c

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 00788c56276ff1f5db5b2250faf0abeadabb16c1..79eb63fdb4b3a37ad6707d696f434bddef463873 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -275,6 +275,7 @@ static mddev_t * mddev_find(dev_t unit)
        spin_lock_init(&new->write_lock);
        init_waitqueue_head(&new->sb_wait);
        new->reshape_position = MaxSector;
+       new->resync_max = MaxSector;
 
        new->queue = blk_alloc_queue(GFP_KERNEL);
        if (!new->queue) {
@@ -2920,6 +2921,43 @@ sync_completed_show(mddev_t *mddev, char *page)
 
 static struct md_sysfs_entry md_sync_completed = __ATTR_RO(sync_completed);
 
+static ssize_t
+max_sync_show(mddev_t *mddev, char *page)
+{
+       if (mddev->resync_max == MaxSector)
+               return sprintf(page, "max\n");
+       else
+               return sprintf(page, "%llu\n",
+                              (unsigned long long)mddev->resync_max);
+}
+static ssize_t
+max_sync_store(mddev_t *mddev, const char *buf, size_t len)
+{
+       if (strncmp(buf, "max", 3) == 0)
+               mddev->resync_max = MaxSector;
+       else {
+               char *ep;
+               unsigned long long max = simple_strtoull(buf, &ep, 10);
+               if (ep == buf || (*ep != 0 && *ep != '\n'))
+                       return -EINVAL;
+               if (max < mddev->resync_max &&
+                   test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
+                       return -EBUSY;
+
+               /* Must be a multiple of chunk_size */
+               if (mddev->chunk_size) {
+                       if (max & (sector_t)((mddev->chunk_size>>9)-1))
+                               return -EINVAL;
+               }
+               mddev->resync_max = max;
+       }
+       wake_up(&mddev->recovery_wait);
+       return len;
+}
+
+static struct md_sysfs_entry md_max_sync =
+__ATTR(sync_max, S_IRUGO|S_IWUSR, max_sync_show, max_sync_store);
+
 static ssize_t
 suspend_lo_show(mddev_t *mddev, char *page)
 {
@@ -3030,6 +3068,7 @@ static struct attribute *md_redundancy_attrs[] = {
        &md_sync_max.attr,
        &md_sync_speed.attr,
        &md_sync_completed.attr,
+       &md_max_sync.attr,
        &md_suspend_lo.attr,
        &md_suspend_hi.attr,
        &md_bitmap.attr,
@@ -3579,6 +3618,7 @@ static int do_md_stop(mddev_t * mddev, int mode)
                mddev->size = 0;
                mddev->raid_disks = 0;
                mddev->recovery_cp = 0;
+               mddev->resync_max = MaxSector;
                mddev->reshape_position = MaxSector;
                mddev->external = 0;
 
@@ -5443,8 +5483,16 @@ void md_do_sync(mddev_t *mddev)
                sector_t sectors;
 
                skipped = 0;
+               if (j >= mddev->resync_max) {
+                       sysfs_notify(&mddev->kobj, NULL, "sync_completed");
+                       wait_event(mddev->recovery_wait,
+                                  mddev->resync_max > j
+                                  || kthread_should_stop());
+               }
+               if (kthread_should_stop())
+                       goto interrupted;
                sectors = mddev->pers->sync_request(mddev, j, &skipped,
-                                           currspeed < speed_min(mddev));
+                                                 currspeed < speed_min(mddev));
                if (sectors == 0) {
                        set_bit(MD_RECOVERY_ERR, &mddev->recovery);
                        goto out;
@@ -5486,15 +5534,9 @@ void md_do_sync(mddev_t *mddev)
                }
 
 
-               if (kthread_should_stop()) {
-                       /*
-                        * got a signal, exit.
-                        */
-                       printk(KERN_INFO 
-                               "md: md_do_sync() got signal ... exiting\n");
-                       set_bit(MD_RECOVERY_INTR, &mddev->recovery);
-                       goto out;
-               }
+               if (kthread_should_stop())
+                       goto interrupted;
+
 
                /*
                 * this loop exits only if either when we are slower than
@@ -5558,9 +5600,22 @@ void md_do_sync(mddev_t *mddev)
 
  skip:
        mddev->curr_resync = 0;
+       mddev->resync_max = MaxSector;
+       sysfs_notify(&mddev->kobj, NULL, "sync_completed");
        wake_up(&resync_wait);
        set_bit(MD_RECOVERY_DONE, &mddev->recovery);
        md_wakeup_thread(mddev->thread);
+       return;
+
+ interrupted:
+       /*
+        * got a signal, exit.
+        */
+       printk(KERN_INFO
+              "md: md_do_sync() got signal ... exiting\n");
+       set_bit(MD_RECOVERY_INTR, &mddev->recovery);
+       goto out;
+
 }
 EXPORT_SYMBOL_GPL(md_do_sync);