5 files changed, 69 insertions, 14 deletions

diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index 5432d07c074d..11108165e264 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -479,9 +479,12 @@ static int bitmap_read_sb(struct bitmap *bitmap)
         int err = -EINVAL;
 
         /* page 0 is the superblock, read it... */
-        if (bitmap->file)
-                bitmap->sb_page = read_page(bitmap->file, 0, bitmap, PAGE_SIZE);
-        else {
+        if (bitmap->file) {
+                loff_t isize = i_size_read(bitmap->file->f_mapping->host);
+                int bytes = isize > PAGE_SIZE ? PAGE_SIZE : isize;
+
+                bitmap->sb_page = read_page(bitmap->file, 0, bitmap, bytes);
+        } else {
                 bitmap->sb_page = read_sb_page(bitmap->mddev, bitmap->offset, 0);
         }
         if (IS_ERR(bitmap->sb_page)) {
@@ -877,7 +880,8 @@ static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
                         int count;
                         /* unmap the old page, we're done with it */
                         if (index == num_pages-1)
-                                count = bytes - index * PAGE_SIZE;
+                                count = bytes + sizeof(bitmap_super_t)
+                                        - index * PAGE_SIZE;
                         else
                                 count = PAGE_SIZE;
                         if (index == 0) {
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index fe7c56e10435..3668b170ea68 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1116,7 +1116,8 @@ static int __bind(struct mapped_device *md, struct dm_table *t)
         if (size != get_capacity(md->disk))
                 memset(&md->geometry, 0, sizeof(md->geometry));
 
-        __set_size(md, size);
+        if (md->suspended_bdev)
+                __set_size(md, size);
         if (size == 0)
                 return 0;
 
@@ -1264,6 +1265,11 @@ int dm_swap_table(struct mapped_device *md, struct dm_table *table)
         if (!dm_suspended(md))
                 goto out;
 
+        /* without bdev, the device size cannot be changed */
+        if (!md->suspended_bdev)
+                if (get_capacity(md->disk) != dm_table_get_size(table))
+                        goto out;
+
         __unbind(md);
         r = __bind(md, table);
 
@@ -1341,11 +1347,14 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
         /* This does not get reverted if there's an error later. */
         dm_table_presuspend_targets(map);
 
-        md->suspended_bdev = bdget_disk(md->disk, 0);
-        if (!md->suspended_bdev) {
-                DMWARN("bdget failed in dm_suspend");
-                r = -ENOMEM;
-                goto flush_and_out;
+        /* bdget() can stall if the pending I/Os are not flushed */
+        if (!noflush) {
+                md->suspended_bdev = bdget_disk(md->disk, 0);
+                if (!md->suspended_bdev) {
+                        DMWARN("bdget failed in dm_suspend");
+                        r = -ENOMEM;
+                        goto flush_and_out;
+                }
         }
 
         /*
@@ -1473,8 +1482,10 @@ int dm_resume(struct mapped_device *md)
 
         unlock_fs(md);
 
-        bdput(md->suspended_bdev);
-        md->suspended_bdev = NULL;
+        if (md->suspended_bdev) {
+                bdput(md->suspended_bdev);
+                md->suspended_bdev = NULL;
+        }
 
         clear_bit(DMF_SUSPENDED, &md->flags);
 
diff --git a/drivers/md/md.c b/drivers/md/md.c
index d1cb45f6d6a9..e8807ea5377d 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1633,7 +1633,8 @@ repeat:
          * and 'events' is odd, we can roll back to the previous clean state */
         if (nospares
             && (mddev->in_sync && mddev->recovery_cp == MaxSector)
-            && (mddev->events & 1))
+            && (mddev->events & 1)
+            && mddev->events != 1)
                 mddev->events--;
         else {
                 /* otherwise we have to go forward and ... */
@@ -3563,6 +3564,8 @@ static int get_bitmap_file(mddev_t * mddev, void __user * arg)
         char *ptr, *buf = NULL;
         int err = -ENOMEM;
 
+        md_allow_write(mddev);
+
         file = kmalloc(sizeof(*file), GFP_KERNEL);
         if (!file)
                 goto out;
@@ -5031,6 +5034,33 @@ void md_write_end(mddev_t *mddev)
         }
 }
 
+/* md_allow_write(mddev)
+ * Calling this ensures that the array is marked 'active' so that writes
+ * may proceed without blocking.  It is important to call this before
+ * attempting a GFP_KERNEL allocation while holding the mddev lock.
+ * Must be called with mddev_lock held.
+ */
+void md_allow_write(mddev_t *mddev)
+{
+        if (!mddev->pers)
+                return;
+        if (mddev->ro)
+                return;
+
+        spin_lock_irq(&mddev->write_lock);
+        if (mddev->in_sync) {
+                mddev->in_sync = 0;
+                set_bit(MD_CHANGE_CLEAN, &mddev->flags);
+                if (mddev->safemode_delay &&
+                    mddev->safemode == 0)
+                        mddev->safemode = 1;
+                spin_unlock_irq(&mddev->write_lock);
+                md_update_sb(mddev, 0);
+        } else
+                spin_unlock_irq(&mddev->write_lock);
+}
+EXPORT_SYMBOL_GPL(md_allow_write);
+
 static DECLARE_WAIT_QUEUE_HEAD(resync_wait);
 
 #define SYNC_MARKS      10
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 164b25dca101..97ee870b265d 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1266,6 +1266,11 @@ static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio)
                                         sbio->bi_sector = r1_bio->sector +
                                                 conf->mirrors[i].rdev->data_offset;
                                         sbio->bi_bdev = conf->mirrors[i].rdev->bdev;
+                                        for (j = 0; j < vcnt ; j++)
+                                                memcpy(page_address(sbio->bi_io_vec[j].bv_page),
+                                                       page_address(pbio->bi_io_vec[j].bv_page),
+                                                       PAGE_SIZE);
+
                                 }
                         }
         }
@@ -2099,6 +2104,8 @@ static int raid1_reshape(mddev_t *mddev)
                 return -EINVAL;
         }
 
+        md_allow_write(mddev);
+
         raid_disks = mddev->raid_disks + mddev->delta_disks;
 
         if (raid_disks < conf->raid_disks) {
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index be008f034ada..467c16982d02 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -405,6 +405,8 @@ static int resize_stripes(raid5_conf_t *conf, int newsize)
         if (newsize <= conf->pool_size)
                 return 0; /* never bother to shrink */
 
+        md_allow_write(conf->mddev);
+
         /* Step 1 */
         sc = kmem_cache_create(conf->cache_name[1-conf->active_name],
                                sizeof(struct stripe_head)+(newsize-1)*sizeof(struct r5dev),
@@ -2678,7 +2680,7 @@ static int chunk_aligned_read(request_queue_t *q, struct bio * raid_bio)
         mdk_rdev_t *rdev;
 
         if (!in_chunk_boundary(mddev, raid_bio)) {
-                printk("chunk_aligned_read : non aligned\n");
+                PRINTK("chunk_aligned_read : non aligned\n");
                 return 0;
         }
         /*
@@ -3250,6 +3252,7 @@ raid5_store_stripe_cache_size(mddev_t *mddev, const char *page, size_t len)
                 else
                         break;
         }
+        md_allow_write(mddev);
         while (new > conf->max_nr_stripes) {
                 if (grow_one_stripe(conf))
                         conf->max_nr_stripes++;