md: fix data corruption when a degraded raid5 array is reshaped

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

diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index fbe477bb2c68ca4005a7f606af18a715edbfc5f9..47818d8249cbf16f125328d39d2be54c0241130a 100644 (file)
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -99,9 +99,14 @@ static void combine_restrictions_low(struct io_restrictions *lhs,
        lhs->max_segment_size =
                min_not_zero(lhs->max_segment_size, rhs->max_segment_size);
 
+       lhs->max_hw_sectors =
+               min_not_zero(lhs->max_hw_sectors, rhs->max_hw_sectors);
+
        lhs->seg_boundary_mask =
                min_not_zero(lhs->seg_boundary_mask, rhs->seg_boundary_mask);
 
+       lhs->bounce_pfn = min_not_zero(lhs->bounce_pfn, rhs->bounce_pfn);
+
        lhs->no_cluster |= rhs->no_cluster;
 }
 
@@ -187,8 +192,10 @@ static int alloc_targets(struct dm_table *t, unsigned int num)
 
        /*
         * Allocate both the target array and offset array at once.
+        * Append an empty entry to catch sectors beyond the end of
+        * the device.
         */
-       n_highs = (sector_t *) dm_vcalloc(num, sizeof(struct dm_target) +
+       n_highs = (sector_t *) dm_vcalloc(num + 1, sizeof(struct dm_target) +
                                          sizeof(sector_t));
        if (!n_highs)
                return -ENOMEM;
@@ -213,12 +220,11 @@ static int alloc_targets(struct dm_table *t, unsigned int num)
 int dm_table_create(struct dm_table **result, int mode,
                    unsigned num_targets, struct mapped_device *md)
 {
-       struct dm_table *t = kmalloc(sizeof(*t), GFP_KERNEL);
+       struct dm_table *t = kzalloc(sizeof(*t), GFP_KERNEL);
 
        if (!t)
                return -ENOMEM;
 
-       memset(t, 0, sizeof(*t));
        INIT_LIST_HEAD(&t->devices);
        atomic_set(&t->holders, 1);
 
@@ -563,10 +569,15 @@ void dm_set_device_limits(struct dm_target *ti, struct block_device *bdev)
        rs->max_segment_size =
                min_not_zero(rs->max_segment_size, q->max_segment_size);
 
+       rs->max_hw_sectors =
+               min_not_zero(rs->max_hw_sectors, q->max_hw_sectors);
+
        rs->seg_boundary_mask =
                min_not_zero(rs->seg_boundary_mask,
                             q->seg_boundary_mask);
 
+       rs->bounce_pfn = min_not_zero(rs->bounce_pfn, q->bounce_pfn);
+
        rs->no_cluster |= !test_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags);
 }
 EXPORT_SYMBOL_GPL(dm_set_device_limits);
@@ -698,6 +709,8 @@ static void check_for_valid_limits(struct io_restrictions *rs)
 {
        if (!rs->max_sectors)
                rs->max_sectors = SAFE_MAX_SECTORS;
+       if (!rs->max_hw_sectors)
+               rs->max_hw_sectors = SAFE_MAX_SECTORS;
        if (!rs->max_phys_segments)
                rs->max_phys_segments = MAX_PHYS_SEGMENTS;
        if (!rs->max_hw_segments)
@@ -708,6 +721,8 @@ static void check_for_valid_limits(struct io_restrictions *rs)
                rs->max_segment_size = MAX_SEGMENT_SIZE;
        if (!rs->seg_boundary_mask)
                rs->seg_boundary_mask = -1;
+       if (!rs->bounce_pfn)
+               rs->bounce_pfn = -1;
 }
 
 int dm_table_add_target(struct dm_table *t, const char *type,
@@ -862,6 +877,9 @@ struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index)
 
 /*
  * Search the btree for the correct target.
+ *
+ * Caller should check returned pointer with dm_target_is_valid()
+ * to trap I/O beyond end of device.
  */
 struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector)
 {
@@ -891,7 +909,9 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q)
        q->max_hw_segments = t->limits.max_hw_segments;
        q->hardsect_size = t->limits.hardsect_size;
        q->max_segment_size = t->limits.max_segment_size;
+       q->max_hw_sectors = t->limits.max_hw_sectors;
        q->seg_boundary_mask = t->limits.seg_boundary_mask;
+       q->bounce_pfn = t->limits.bounce_pfn;
        if (t->limits.no_cluster)
                q->queue_flags &= ~(1 << QUEUE_FLAG_CLUSTER);
        else
@@ -994,8 +1014,7 @@ void dm_table_unplug_all(struct dm_table *t)
                struct dm_dev *dd = list_entry(d, struct dm_dev, list);
                struct request_queue *q = bdev_get_queue(dd->bdev);
 
-               if (q->unplug_fn)
-                       q->unplug_fn(q);
+               blk_unplug(q);
        }
 }