cfq-iosched: requests "in flight" vs "in driver" clarification

[safe/jmp/linux-2.6] / block / blk-settings.c

diff --git a/block/blk-settings.c b/block/blk-settings.c
index 3c53b0b..31e7a93 100644 (file)
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -91,8 +91,7 @@ EXPORT_SYMBOL_GPL(blk_queue_lld_busy);
  */
 void blk_set_default_limits(struct queue_limits *lim)
 {
-       lim->max_phys_segments = MAX_PHYS_SEGMENTS;
-       lim->max_hw_segments = MAX_HW_SEGMENTS;
+       lim->max_segments = BLK_MAX_SEGMENTS;
        lim->seg_boundary_mask = BLK_SEG_BOUNDARY_MASK;
        lim->max_segment_size = BLK_MAX_SEGMENT_SIZE;
        lim->max_sectors = BLK_DEF_MAX_SECTORS;
@@ -154,7 +153,7 @@ void blk_queue_make_request(struct request_queue *q, make_request_fn *mfn)
        q->unplug_timer.data = (unsigned long)q;
 
        blk_set_default_limits(&q->limits);
-       blk_queue_max_sectors(q, BLK_SAFE_MAX_SECTORS);
+       blk_queue_max_hw_sectors(q, BLK_SAFE_MAX_SECTORS);
 
        /*
         * If the caller didn't supply a lock, fall back to our embedded
@@ -210,7 +209,7 @@ void blk_queue_bounce_limit(struct request_queue *q, u64 dma_mask)
 EXPORT_SYMBOL(blk_queue_bounce_limit);
 
 /**
- * blk_queue_max_sectors - set max sectors for a request for this queue
+ * blk_queue_max_hw_sectors - set max sectors for a request for this queue
  * @q:  the request queue for the device
  * @max_hw_sectors:  max hardware sectors in the usual 512b unit
  *
@@ -225,7 +224,7 @@ EXPORT_SYMBOL(blk_queue_bounce_limit);
  *    per-device basis in /sys/block/<device>/queue/max_sectors_kb.
  *    The soft limit can not exceed max_hw_sectors.
  **/
-void blk_queue_max_sectors(struct request_queue *q, unsigned int max_hw_sectors)
+void blk_queue_max_hw_sectors(struct request_queue *q, unsigned int max_hw_sectors)
 {
        if ((max_hw_sectors << 9) < PAGE_CACHE_SIZE) {
                max_hw_sectors = 1 << (PAGE_CACHE_SHIFT - 9);
@@ -237,7 +236,7 @@ void blk_queue_max_sectors(struct request_queue *q, unsigned int max_hw_sectors)
        q->limits.max_sectors = min_t(unsigned int, max_hw_sectors,
                                      BLK_DEF_MAX_SECTORS);
 }
-EXPORT_SYMBOL(blk_queue_max_sectors);
+EXPORT_SYMBOL(blk_queue_max_hw_sectors);
 
 /**
  * blk_queue_max_discard_sectors - set max sectors for a single discard
@@ -252,17 +251,15 @@ void blk_queue_max_discard_sectors(struct request_queue *q,
 EXPORT_SYMBOL(blk_queue_max_discard_sectors);
 
 /**
- * blk_queue_max_phys_segments - set max phys segments for a request for this queue
+ * blk_queue_max_segments - set max hw segments for a request for this queue
  * @q:  the request queue for the device
  * @max_segments:  max number of segments
  *
  * Description:
  *    Enables a low level driver to set an upper limit on the number of
- *    physical data segments in a request.  This would be the largest sized
- *    scatter list the driver could handle.
+ *    hw data segments in a request.
  **/
-void blk_queue_max_phys_segments(struct request_queue *q,
-                                unsigned short max_segments)
+void blk_queue_max_segments(struct request_queue *q, unsigned short max_segments)
 {
        if (!max_segments) {
                max_segments = 1;
@@ -270,33 +267,9 @@ void blk_queue_max_phys_segments(struct request_queue *q,
                       __func__, max_segments);
        }
 
-       q->limits.max_phys_segments = max_segments;
+       q->limits.max_segments = max_segments;
 }
-EXPORT_SYMBOL(blk_queue_max_phys_segments);
-
-/**
- * blk_queue_max_hw_segments - set max hw segments for a request for this queue
- * @q:  the request queue for the device
- * @max_segments:  max number of segments
- *
- * Description:
- *    Enables a low level driver to set an upper limit on the number of
- *    hw data segments in a request.  This would be the largest number of
- *    address/length pairs the host adapter can actually give at once
- *    to the device.
- **/
-void blk_queue_max_hw_segments(struct request_queue *q,
-                              unsigned short max_segments)
-{
-       if (!max_segments) {
-               max_segments = 1;
-               printk(KERN_INFO "%s: set to minimum %d\n",
-                      __func__, max_segments);
-       }
-
-       q->limits.max_hw_segments = max_segments;
-}
-EXPORT_SYMBOL(blk_queue_max_hw_segments);
+EXPORT_SYMBOL(blk_queue_max_segments);
 
 /**
  * blk_queue_max_segment_size - set max segment size for blk_rq_map_sg
@@ -531,11 +504,7 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
        t->seg_boundary_mask = min_not_zero(t->seg_boundary_mask,
                                            b->seg_boundary_mask);
 
-       t->max_phys_segments = min_not_zero(t->max_phys_segments,
-                                           b->max_phys_segments);
-
-       t->max_hw_segments = min_not_zero(t->max_hw_segments,
-                                         b->max_hw_segments);
+       t->max_segments = min_not_zero(t->max_segments, b->max_segments);
 
        t->max_segment_size = min_not_zero(t->max_segment_size,
                                           b->max_segment_size);
@@ -739,22 +708,19 @@ EXPORT_SYMBOL(blk_queue_update_dma_pad);
  * does is adjust the queue so that the buf is always appended
  * silently to the scatterlist.
  *
- * Note: This routine adjusts max_hw_segments to make room for
- * appending the drain buffer.  If you call
- * blk_queue_max_hw_segments() or blk_queue_max_phys_segments() after
- * calling this routine, you must set the limit to one fewer than your
- * device can support otherwise there won't be room for the drain
- * buffer.
+ * Note: This routine adjusts max_hw_segments to make room for appending
+ * the drain buffer.  If you call blk_queue_max_segments() after calling
+ * this routine, you must set the limit to one fewer than your device
+ * can support otherwise there won't be room for the drain buffer.
  */
 int blk_queue_dma_drain(struct request_queue *q,
                               dma_drain_needed_fn *dma_drain_needed,
                               void *buf, unsigned int size)
 {
-       if (queue_max_hw_segments(q) < 2 || queue_max_phys_segments(q) < 2)
+       if (queue_max_segments(q) < 2)
                return -EINVAL;
        /* make room for appending the drain */
-       blk_queue_max_hw_segments(q, queue_max_hw_segments(q) - 1);
-       blk_queue_max_phys_segments(q, queue_max_phys_segments(q) - 1);
+       blk_queue_max_segments(q, queue_max_segments(q) - 1);
        q->dma_drain_needed = dma_drain_needed;
        q->dma_drain_buffer = buf;
        q->dma_drain_size = size;