1 files changed, 15 insertions, 1 deletions

diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index e298d8d11f24..47818d8249cb 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -99,6 +99,9 @@ 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);
 
@@ -189,8 +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;
@@ -564,6 +569,9 @@ 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);
@@ -701,6 +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)
@@ -867,6 +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)
 {
@@ -896,6 +909,7 @@ 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)