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>

arch/um/drivers/ubd_kern.c

@@ -849,7 +849,7 @@ static int ubd_add(int n, char **error_out)
 	}
 	ubd_dev->queue->queuedata = ubd_dev;
 
-	blk_queue_max_hw_segments(ubd_dev->queue, MAX_SG);
+	blk_queue_max_segments(ubd_dev->queue, MAX_SG);
 	err = ubd_disk_register(UBD_MAJOR, ubd_dev->size, n, &ubd_gendisk[n]);
 	if(err){
 		*error_out = "Failed to register device";

block/blk-core.c

@@ -1614,8 +1614,7 @@ int blk_rq_check_limits(struct request_queue *q, struct request *rq)
 	 * 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;
 	}

block/blk-merge.c

@@ -206,8 +206,7 @@ static inline int ll_new_hw_segment(struct request_queue *q,
 {
 	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 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req,
 		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... */

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;
@@ -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;

drivers/ata/sata_nv.c

@@ -772,7 +772,7 @@ static int nv_adma_slave_config(struct scsi_device *sdev)
 	}
 
 	blk_queue_segment_boundary(sdev->request_queue, segment_boundary);
-	blk_queue_max_hw_segments(sdev->request_queue, sg_tablesize);
+	blk_queue_max_segments(sdev->request_queue, sg_tablesize);
 	ata_port_printk(ap, KERN_INFO,
 		"DMA mask 0x%llX, segment boundary 0x%lX, hw segs %hu\n",
 		(unsigned long long)*ap->host->dev->dma_mask,

drivers/block/DAC960.c

@@ -2534,7 +2534,7 @@ static bool DAC960_RegisterBlockDevice(DAC960_Controller_T *Controller)
   	blk_queue_bounce_limit(RequestQueue, Controller->BounceBufferLimit);
   	RequestQueue->queuedata = Controller;
   	blk_queue_max_hw_segments(RequestQueue, Controller->DriverScatterGatherLimit);
-	blk_queue_max_phys_segments(RequestQueue, Controller->DriverScatterGatherLimit);
+	blk_queue_max_segments(RequestQueue, Controller->DriverScatterGatherLimit);
 	blk_queue_max_hw_sectors(RequestQueue, Controller->MaxBlocksPerCommand);
 	disk->queue = RequestQueue;
 	sprintf(disk->disk_name, "rd/c%dd%d", Controller->ControllerNumber, n);

drivers/block/cciss.c

@@ -1797,10 +1797,7 @@ static int cciss_add_disk(ctlr_info_t *h, struct gendisk *disk,
 	blk_queue_bounce_limit(disk->queue, h->pdev->dma_mask);
 
 	/* This is a hardware imposed limit. */
-	blk_queue_max_hw_segments(disk->queue, h->maxsgentries);
-
-	/* This is a limit in the driver and could be eliminated. */
-	blk_queue_max_phys_segments(disk->queue, h->maxsgentries);
+	blk_queue_max_segments(disk->queue, h->maxsgentries);
 
 	blk_queue_max_hw_sectors(disk->queue, h->cciss_max_sectors);
 

drivers/block/cpqarray.c

@@ -448,11 +448,8 @@ static int __init cpqarray_register_ctlr( int i, struct pci_dev *pdev)
 		blk_queue_bounce_limit(q, hba[i]->pci_dev->dma_mask);
 
 	/* This is a hardware imposed limit. */
-	blk_queue_max_hw_segments(q, SG_MAX);
+	blk_queue_max_segments(q, SG_MAX);
 
-	/* This is a driver limit and could be eliminated. */
-	blk_queue_max_phys_segments(q, SG_MAX);
-	
 	init_timer(&hba[i]->timer);
 	hba[i]->timer.expires = jiffies + IDA_TIMER;
 	hba[i]->timer.data = (unsigned long)hba[i];

drivers/block/drbd/drbd_nl.c

@@ -710,8 +710,7 @@ void drbd_setup_queue_param(struct drbd_conf *mdev, unsigned int max_seg_s) __mu
 	max_seg_s = min(queue_max_sectors(b) * queue_logical_block_size(b), max_seg_s);
 
 	blk_queue_max_hw_sectors(q, max_seg_s >> 9);
-	blk_queue_max_phys_segments(q, max_segments ? max_segments : MAX_PHYS_SEGMENTS);
-	blk_queue_max_hw_segments(q, max_segments ? max_segments : MAX_HW_SEGMENTS);
+	blk_queue_max_segments(q, max_segments ? max_segments : BLK_MAX_SEGMENTS);
 	blk_queue_max_segment_size(q, max_seg_s);
 	blk_queue_logical_block_size(q, 512);
 	blk_queue_segment_boundary(q, PAGE_SIZE-1);

drivers/block/paride/pf.c

@@ -956,8 +956,7 @@ static int __init pf_init(void)
 		return -ENOMEM;
 	}
 
-	blk_queue_max_phys_segments(pf_queue, cluster);
-	blk_queue_max_hw_segments(pf_queue, cluster);
+	blk_queue_max_segments(pf_queue, cluster);
 
 	for (pf = units, unit = 0; unit < PF_UNITS; pf++, unit++) {
 		struct gendisk *disk = pf->disk;

drivers/block/pktcdvd.c

@@ -950,14 +950,14 @@ static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
 {
 	if ((pd->settings.size << 9) / CD_FRAMESIZE
-	    <= queue_max_phys_segments(q)) {
+	    <= queue_max_segments(q)) {
 		/*
 		 * The cdrom device can handle one segment/frame
 		 */
 		clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 		return 0;
 	} else if ((pd->settings.size << 9) / PAGE_SIZE
-		   <= queue_max_phys_segments(q)) {
+		   <= queue_max_segments(q)) {
 		/*
 		 * We can handle this case at the expense of some extra memory
 		 * copies during write operations

drivers/block/ps3disk.c

@@ -482,8 +482,7 @@ static int __devinit ps3disk_probe(struct ps3_system_bus_device *_dev)
 	blk_queue_ordered(queue, QUEUE_ORDERED_DRAIN_FLUSH,
 			  ps3disk_prepare_flush);
 
-	blk_queue_max_phys_segments(queue, -1);
-	blk_queue_max_hw_segments(queue, -1);
+	blk_queue_max_segments(queue, -1);
 	blk_queue_max_segment_size(queue, dev->bounce_size);
 
 	gendisk = alloc_disk(PS3DISK_MINORS);

drivers/block/ps3vram.c

@@ -751,8 +751,7 @@ static int __devinit ps3vram_probe(struct ps3_system_bus_device *dev)
 	priv->queue = queue;
 	queue->queuedata = dev;
 	blk_queue_make_request(queue, ps3vram_make_request);
-	blk_queue_max_phys_segments(queue, MAX_PHYS_SEGMENTS);
-	blk_queue_max_hw_segments(queue, MAX_HW_SEGMENTS);
+	blk_queue_max_segments(queue, BLK_MAX_HW_SEGMENTS);
 	blk_queue_max_segment_size(queue, BLK_MAX_SEGMENT_SIZE);
 	blk_queue_max_hw_sectors(queue, BLK_SAFE_MAX_SECTORS);
 

drivers/block/sunvdc.c

@@ -691,8 +691,7 @@ static int probe_disk(struct vdc_port *port)
 
 	port->disk = g;
 
-	blk_queue_max_hw_segments(q, port->ring_cookies);
-	blk_queue_max_phys_segments(q, port->ring_cookies);
+	blk_queue_max_segments(q, port->ring_cookies);
 	blk_queue_max_hw_sectors(q, port->max_xfer_size);
 	g->major = vdc_major;
 	g->first_minor = port->vio.vdev->dev_no << PARTITION_SHIFT;

drivers/block/sx8.c

@@ -1518,8 +1518,7 @@ static int carm_init_disks(struct carm_host *host)
 			break;
 		}
 		disk->queue = q;
-		blk_queue_max_hw_segments(q, CARM_MAX_REQ_SG);
-		blk_queue_max_phys_segments(q, CARM_MAX_REQ_SG);
+		blk_queue_max_segments(q, CARM_MAX_REQ_SG);
 		blk_queue_segment_boundary(q, CARM_SG_BOUNDARY);
 
 		q->queuedata = port;

drivers/block/ub.c

@@ -2320,8 +2320,7 @@ static int ub_probe_lun(struct ub_dev *sc, int lnum)
 	disk->queue = q;
 
 	blk_queue_bounce_limit(q, BLK_BOUNCE_HIGH);
-	blk_queue_max_hw_segments(q, UB_MAX_REQ_SG);
-	blk_queue_max_phys_segments(q, UB_MAX_REQ_SG);
+	blk_queue_max_segments(q, UB_MAX_REQ_SG);
 	blk_queue_segment_boundary(q, 0xffffffff);	/* Dubious. */
 	blk_queue_max_hw_sectors(q, UB_MAX_SECTORS);
 	blk_queue_logical_block_size(q, lun->capacity.bsize);

drivers/block/viodasd.c

@@ -471,8 +471,7 @@ retry:
 	}
 
 	d->disk = g;
-	blk_queue_max_hw_segments(q, VIOMAXBLOCKDMA);
-	blk_queue_max_phys_segments(q, VIOMAXBLOCKDMA);
+	blk_queue_max_segments(q, VIOMAXBLOCKDMA);
 	blk_queue_max_hw_sectors(q, VIODASD_MAXSECTORS);
 	g->major = VIODASD_MAJOR;
 	g->first_minor = dev_no << PARTITION_SHIFT;

drivers/block/xen-blkfront.c

@@ -353,8 +353,7 @@ static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size)
 	blk_queue_max_segment_size(rq, PAGE_SIZE);
 
 	/* Ensure a merged request will fit in a single I/O ring slot. */
-	blk_queue_max_phys_segments(rq, BLKIF_MAX_SEGMENTS_PER_REQUEST);
-	blk_queue_max_hw_segments(rq, BLKIF_MAX_SEGMENTS_PER_REQUEST);
+	blk_queue_max_segments(rq, BLKIF_MAX_SEGMENTS_PER_REQUEST);
 
 	/* Make sure buffer addresses are sector-aligned. */
 	blk_queue_dma_alignment(rq, 511);

drivers/cdrom/gdrom.c

@@ -741,7 +741,7 @@ static int __devinit probe_gdrom_setupqueue(void)
 {
 	blk_queue_logical_block_size(gd.gdrom_rq, GDROM_HARD_SECTOR);
 	/* using DMA so memory will need to be contiguous */
-	blk_queue_max_hw_segments(gd.gdrom_rq, 1);
+	blk_queue_max_segments(gd.gdrom_rq, 1);
 	/* set a large max size to get most from DMA */
 	blk_queue_max_segment_size(gd.gdrom_rq, 0x40000);
 	gd.disk->queue = gd.gdrom_rq;

drivers/cdrom/viocd.c

@@ -616,8 +616,7 @@ static int viocd_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 	gendisk->first_minor = deviceno;
 	strncpy(gendisk->disk_name, c->name,
 			sizeof(gendisk->disk_name));
-	blk_queue_max_hw_segments(q, 1);
-	blk_queue_max_phys_segments(q, 1);
+	blk_queue_max_segments(q, 1);
 	blk_queue_max_hw_sectors(q, 4096 / 512);
 	gendisk->queue = q;
 	gendisk->fops = &viocd_fops;