block: Consolidate phys_segment and hw_segment limits
Except for SCSI no device drivers distinguish between physical and
hardware segment limits. Consolidate the two into a single segment
limit.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/block/blk-core.c b/block/blk-core.c
index 36c0dee..9fe174d 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1614,8 +1614,7 @@
* limitation.
*/
blk_recalc_rq_segments(rq);
- if (rq->nr_phys_segments > queue_max_phys_segments(q) ||
- rq->nr_phys_segments > queue_max_hw_segments(q)) {
+ if (rq->nr_phys_segments > queue_max_segments(q)) {
printk(KERN_ERR "%s: over max segments limit.\n", __func__);
return -EIO;
}
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 99cb5cf..5e7dc99 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -206,8 +206,7 @@
{
int nr_phys_segs = bio_phys_segments(q, bio);
- if (req->nr_phys_segments + nr_phys_segs > queue_max_hw_segments(q) ||
- req->nr_phys_segments + nr_phys_segs > queue_max_phys_segments(q)) {
+ if (req->nr_phys_segments + nr_phys_segs > queue_max_segments(q)) {
req->cmd_flags |= REQ_NOMERGE;
if (req == q->last_merge)
q->last_merge = NULL;
@@ -300,10 +299,7 @@
total_phys_segments--;
}
- if (total_phys_segments > queue_max_phys_segments(q))
- return 0;
-
- if (total_phys_segments > queue_max_hw_segments(q))
+ if (total_phys_segments > queue_max_segments(q))
return 0;
/* Merge is OK... */
diff --git a/block/blk-settings.c b/block/blk-settings.c
index 61afae9..31e7a93 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -91,8 +91,7 @@
*/
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;
@@ -252,17 +251,15 @@
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 @@
__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 @@
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 @@
* 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;