block: set the bounce_pfn to the actual DMA limit rather than to max memory

[linux-2.6-block.git] / block / blk-settings.c

diff --git a/block/blk-settings.c b/block/blk-settings.c
index f5ed5a1187ba8564527b70f682328b31eea4549a..a3600a7ab8bb7cede0bddfefe92180617045d525 100644 (file)
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -36,6 +36,23 @@ void blk_queue_prep_rq(struct request_queue *q, prep_rq_fn *pfn)
 }
 EXPORT_SYMBOL(blk_queue_prep_rq);
 
+/**
+ * blk_queue_unprep_rq - set an unprepare_request function for queue
+ * @q:         queue
+ * @ufn:       unprepare_request function
+ *
+ * It's possible for a queue to register an unprepare_request callback
+ * which is invoked before the request is finally completed. The goal
+ * of the function is to deallocate any data that was allocated in the
+ * prepare_request callback.
+ *
+ */
+void blk_queue_unprep_rq(struct request_queue *q, unprep_rq_fn *ufn)
+{
+       q->unprep_rq_fn = ufn;
+}
+EXPORT_SYMBOL(blk_queue_unprep_rq);
+
 /**
  * blk_queue_merge_bvec - set a merge_bvec function for queue
  * @q:         queue
@@ -94,6 +111,7 @@ EXPORT_SYMBOL_GPL(blk_queue_lld_busy);
 void blk_set_default_limits(struct queue_limits *lim)
 {
        lim->max_segments = BLK_MAX_SEGMENTS;
+       lim->max_integrity_segments = 0;
        lim->seg_boundary_mask = BLK_SEG_BOUNDARY_MASK;
        lim->max_segment_size = BLK_MAX_SEGMENT_SIZE;
        lim->max_sectors = BLK_DEF_MAX_SECTORS;
@@ -196,7 +214,7 @@ void blk_queue_bounce_limit(struct request_queue *q, u64 dma_mask)
         */
        if (b_pfn < (min_t(u64, 0xffffffffUL, BLK_BOUNCE_HIGH) >> PAGE_SHIFT))
                dma = 1;
-       q->limits.bounce_pfn = max_low_pfn;
+       q->limits.bounce_pfn = max(max_low_pfn, b_pfn);
 #else
        if (b_pfn < blk_max_low_pfn)
                dma = 1;
@@ -438,11 +456,6 @@ void blk_queue_io_opt(struct request_queue *q, unsigned int opt)
 }
 EXPORT_SYMBOL(blk_queue_io_opt);
 
-/*
- * Returns the minimum that is _not_ zero, unless both are zero.
- */
-#define min_not_zero(l, r) (l == 0) ? r : ((r == 0) ? l : min(l, r))
-
 /**
  * blk_queue_stack_limits - inherit underlying queue limits for stacked drivers
  * @t: the stacking driver (top)
@@ -497,6 +510,8 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
                                            b->seg_boundary_mask);
 
        t->max_segments = min_not_zero(t->max_segments, b->max_segments);
+       t->max_integrity_segments = min_not_zero(t->max_integrity_segments,
+                                                b->max_integrity_segments);
 
        t->max_segment_size = min_not_zero(t->max_segment_size,
                                           b->max_segment_size);