block: remove support for bio remapping from ->make_request

There is very little benefit in allowing to let a ->make_request instance update the bios device and sector and loop around it in __generic_make_request when we can archive the same through calling generic_make_request from the driver and letting the loop in generic_make_request handle it. Note that various drivers got the return value from ->make_request and returned non-zero values for errors. Signed-off-by: Christoph Hellwig <[email protected]> Acked-by: NeilBrown <[email protected]> Signed-off-by: Jens Axboe <[email protected]>
rtvt123 · Sep 12, 2011 · 5a7bbad · 5a7bbad
1 parent c20e8de
commit 5a7bbad
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Showing 25 changed files with 151 additions and 215 deletions.
diff --git a/arch/m68k/emu/nfblock.c b/arch/m68k/emu/nfblock.c
@@ -59,7 +59,7 @@ struct nfhd_device {
 	struct gendisk *disk;
 };
 
-static int nfhd_make_request(struct request_queue *queue, struct bio *bio)
+static void nfhd_make_request(struct request_queue *queue, struct bio *bio)
 {
 	struct nfhd_device *dev = queue->queuedata;
 	struct bio_vec *bvec;
@@ -76,7 +76,6 @@ static int nfhd_make_request(struct request_queue *queue, struct bio *bio)
 		sec += len;
 	}
 	bio_endio(bio, 0);
-	return 0;
 }
 
 static int nfhd_getgeo(struct block_device *bdev, struct hd_geometry *geo)

diff --git a/arch/powerpc/sysdev/axonram.c b/arch/powerpc/sysdev/axonram.c
@@ -104,7 +104,7 @@ axon_ram_irq_handler(int irq, void *dev)
  * axon_ram_make_request - make_request() method for block device
  * @queue, @bio: see blk_queue_make_request()
  */
-static int
+static void
 axon_ram_make_request(struct request_queue *queue, struct bio *bio)
 {
 	struct axon_ram_bank *bank = bio->bi_bdev->bd_disk->private_data;
@@ -113,16 +113,14 @@ axon_ram_make_request(struct request_queue *queue, struct bio *bio)
 	struct bio_vec *vec;
 	unsigned int transfered;
 	unsigned short idx;
-	int rc = 0;
 
 	phys_mem = bank->io_addr + (bio->bi_sector << AXON_RAM_SECTOR_SHIFT);
 	phys_end = bank->io_addr + bank->size;
 	transfered = 0;
 	bio_for_each_segment(vec, bio, idx) {
 		if (unlikely(phys_mem + vec->bv_len > phys_end)) {
 			bio_io_error(bio);
-			rc = -ERANGE;
-			break;
+			return;
 		}
 
 		user_mem = page_address(vec->bv_page) + vec->bv_offset;
@@ -135,8 +133,6 @@ axon_ram_make_request(struct request_queue *queue, struct bio *bio)
 		transfered += vec->bv_len;
 	}
 	bio_endio(bio, 0);
-
-	return rc;
 }
 
 /**

diff --git a/block/blk-core.c b/block/blk-core.c
@@ -1211,7 +1211,7 @@ void init_request_from_bio(struct request *req, struct bio *bio)
 	blk_rq_bio_prep(req->q, req, bio);
 }
 
-int blk_queue_bio(struct request_queue *q, struct bio *bio)
+void blk_queue_bio(struct request_queue *q, struct bio *bio)
 {
 	const bool sync = !!(bio->bi_rw & REQ_SYNC);
 	struct blk_plug *plug;
@@ -1236,7 +1236,7 @@ int blk_queue_bio(struct request_queue *q, struct bio *bio)
 	 * any locks.
 	 */
 	if (attempt_plug_merge(current, q, bio))
-		goto out;
+		return;
 
 	spin_lock_irq(q->queue_lock);
 
@@ -1312,8 +1312,6 @@ int blk_queue_bio(struct request_queue *q, struct bio *bio)
 out_unlock:
 		spin_unlock_irq(q->queue_lock);
 	}
-out:
-	return 0;
 }
 EXPORT_SYMBOL_GPL(blk_queue_bio);	/* for device mapper only */
 
@@ -1441,112 +1439,85 @@ static inline int bio_check_eod(struct bio *bio, unsigned int nr_sectors)
 static inline void __generic_make_request(struct bio *bio)
 {
 	struct request_queue *q;
-	sector_t old_sector;
-	int ret, nr_sectors = bio_sectors(bio);
-	dev_t old_dev;
+	int nr_sectors = bio_sectors(bio);
 	int err = -EIO;
+	char b[BDEVNAME_SIZE];
+	struct hd_struct *part;
 
 	might_sleep();
 
 	if (bio_check_eod(bio, nr_sectors))
 		goto end_io;
 
-	/*
-	 * Resolve the mapping until finished. (drivers are
-	 * still free to implement/resolve their own stacking
-	 * by explicitly returning 0)
-	 *
-	 * NOTE: we don't repeat the blk_size check for each new device.
-	 * Stacking drivers are expected to know what they are doing.
-	 */
-	old_sector = -1;
-	old_dev = 0;
-	do {
-		char b[BDEVNAME_SIZE];
-		struct hd_struct *part;
-
-		q = bdev_get_queue(bio->bi_bdev);
-		if (unlikely(!q)) {
-			printk(KERN_ERR
-			       "generic_make_request: Trying to access "
-				"nonexistent block-device %s (%Lu)\n",
-				bdevname(bio->bi_bdev, b),
-				(long long) bio->bi_sector);
-			goto end_io;
-		}
-
-		if (unlikely(!(bio->bi_rw & REQ_DISCARD) &&
-			     nr_sectors > queue_max_hw_sectors(q))) {
-			printk(KERN_ERR "bio too big device %s (%u > %u)\n",
-			       bdevname(bio->bi_bdev, b),
-			       bio_sectors(bio),
-			       queue_max_hw_sectors(q));
-			goto end_io;
-		}
-
-		if (unlikely(test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)))
-			goto end_io;
-
-		part = bio->bi_bdev->bd_part;
-		if (should_fail_request(part, bio->bi_size) ||
-		    should_fail_request(&part_to_disk(part)->part0,
-					bio->bi_size))
-			goto end_io;
+	q = bdev_get_queue(bio->bi_bdev);
+	if (unlikely(!q)) {
+		printk(KERN_ERR
+		       "generic_make_request: Trying to access "
+			"nonexistent block-device %s (%Lu)\n",
+			bdevname(bio->bi_bdev, b),
+			(long long) bio->bi_sector);
+		goto end_io;
+	}
 
-		/*
-		 * If this device has partitions, remap block n
-		 * of partition p to block n+start(p) of the disk.
-		 */
-		blk_partition_remap(bio);
+	if (unlikely(!(bio->bi_rw & REQ_DISCARD) &&
+		     nr_sectors > queue_max_hw_sectors(q))) {
+		printk(KERN_ERR "bio too big device %s (%u > %u)\n",
+		       bdevname(bio->bi_bdev, b),
+		       bio_sectors(bio),
+		       queue_max_hw_sectors(q));
+		goto end_io;
+	}
 
-		if (bio_integrity_enabled(bio) && bio_integrity_prep(bio))
-			goto end_io;
+	if (unlikely(test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)))
+		goto end_io;
 
-		if (old_sector != -1)
-			trace_block_bio_remap(q, bio, old_dev, old_sector);
+	part = bio->bi_bdev->bd_part;
+	if (should_fail_request(part, bio->bi_size) ||
+	    should_fail_request(&part_to_disk(part)->part0,
+				bio->bi_size))
+		goto end_io;
 
-		old_sector = bio->bi_sector;
-		old_dev = bio->bi_bdev->bd_dev;
+	/*
+	 * If this device has partitions, remap block n
+	 * of partition p to block n+start(p) of the disk.
+	 */
+	blk_partition_remap(bio);
 
-		if (bio_check_eod(bio, nr_sectors))
-			goto end_io;
+	if (bio_integrity_enabled(bio) && bio_integrity_prep(bio))
+		goto end_io;
 
-		/*
-		 * Filter flush bio's early so that make_request based
-		 * drivers without flush support don't have to worry
-		 * about them.
-		 */
-		if ((bio->bi_rw & (REQ_FLUSH | REQ_FUA)) && !q->flush_flags) {
-			bio->bi_rw &= ~(REQ_FLUSH | REQ_FUA);
-			if (!nr_sectors) {
-				err = 0;
-				goto end_io;
-			}
-		}
+	if (bio_check_eod(bio, nr_sectors))
+		goto end_io;
 
-		if ((bio->bi_rw & REQ_DISCARD) &&
-		    (!blk_queue_discard(q) ||
-		     ((bio->bi_rw & REQ_SECURE) &&
-		      !blk_queue_secdiscard(q)))) {
-			err = -EOPNOTSUPP;
+	/*
+	 * Filter flush bio's early so that make_request based
+	 * drivers without flush support don't have to worry
+	 * about them.
+	 */
+	if ((bio->bi_rw & (REQ_FLUSH | REQ_FUA)) && !q->flush_flags) {
+		bio->bi_rw &= ~(REQ_FLUSH | REQ_FUA);
+		if (!nr_sectors) {
+			err = 0;
 			goto end_io;
 		}
+	}
 
-		if (blk_throtl_bio(q, &bio))
-			goto end_io;
-
-		/*
-		 * If bio = NULL, bio has been throttled and will be submitted
-		 * later.
-		 */
-		if (!bio)
-			break;
-
-		trace_block_bio_queue(q, bio);
+	if ((bio->bi_rw & REQ_DISCARD) &&
+	    (!blk_queue_discard(q) ||
+	     ((bio->bi_rw & REQ_SECURE) &&
+	      !blk_queue_secdiscard(q)))) {
+		err = -EOPNOTSUPP;
+		goto end_io;
+	}
 
-		ret = q->make_request_fn(q, bio);
-	} while (ret);
+	if (blk_throtl_bio(q, &bio))
+		goto end_io;
 
+	/* if bio = NULL, bio has been throttled and will be submitted later. */
+	if (!bio)
+		return;
+	trace_block_bio_queue(q, bio);
+	q->make_request_fn(q, bio);
 	return;
 
 end_io:

diff --git a/drivers/block/aoe/aoeblk.c b/drivers/block/aoe/aoeblk.c
@@ -159,7 +159,7 @@ aoeblk_release(struct gendisk *disk, fmode_t mode)
 	return 0;
 }
 
-static int
+static void
 aoeblk_make_request(struct request_queue *q, struct bio *bio)
 {
 	struct sk_buff_head queue;
@@ -172,25 +172,25 @@ aoeblk_make_request(struct request_queue *q, struct bio *bio)
 	if (bio == NULL) {
 		printk(KERN_ERR "aoe: bio is NULL\n");
 		BUG();
-		return 0;
+		return;
 	}
 	d = bio->bi_bdev->bd_disk->private_data;
 	if (d == NULL) {
 		printk(KERN_ERR "aoe: bd_disk->private_data is NULL\n");
 		BUG();
 		bio_endio(bio, -ENXIO);
-		return 0;
+		return;
 	} else if (bio->bi_io_vec == NULL) {
 		printk(KERN_ERR "aoe: bi_io_vec is NULL\n");
 		BUG();
 		bio_endio(bio, -ENXIO);
-		return 0;
+		return;
 	}
 	buf = mempool_alloc(d->bufpool, GFP_NOIO);
 	if (buf == NULL) {
 		printk(KERN_INFO "aoe: buf allocation failure\n");
 		bio_endio(bio, -ENOMEM);
-		return 0;
+		return;
 	}
 	memset(buf, 0, sizeof(*buf));
 	INIT_LIST_HEAD(&buf->bufs);
@@ -211,7 +211,7 @@ aoeblk_make_request(struct request_queue *q, struct bio *bio)
 		spin_unlock_irqrestore(&d->lock, flags);
 		mempool_free(buf, d->bufpool);
 		bio_endio(bio, -ENXIO);
-		return 0;
+		return;
 	}
 
 	list_add_tail(&buf->bufs, &d->bufq);
@@ -222,8 +222,6 @@ aoeblk_make_request(struct request_queue *q, struct bio *bio)
 
 	spin_unlock_irqrestore(&d->lock, flags);
 	aoenet_xmit(&queue);
-
-	return 0;
 }
 
 static int

diff --git a/drivers/block/brd.c b/drivers/block/brd.c
@@ -323,7 +323,7 @@ static int brd_do_bvec(struct brd_device *brd, struct page *page,
 	return err;
 }
 
-static int brd_make_request(struct request_queue *q, struct bio *bio)
+static void brd_make_request(struct request_queue *q, struct bio *bio)
 {
 	struct block_device *bdev = bio->bi_bdev;
 	struct brd_device *brd = bdev->bd_disk->private_data;
@@ -359,8 +359,6 @@ static int brd_make_request(struct request_queue *q, struct bio *bio)
 
 out:
 	bio_endio(bio, err);
-
-	return 0;
 }
 
 #ifdef CONFIG_BLK_DEV_XIP

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
@@ -1507,7 +1507,7 @@ extern void drbd_free_mdev(struct drbd_conf *mdev);
 extern int proc_details;
 
 /* drbd_req */
-extern int drbd_make_request(struct request_queue *q, struct bio *bio);
+extern void drbd_make_request(struct request_queue *q, struct bio *bio);
 extern int drbd_read_remote(struct drbd_conf *mdev, struct drbd_request *req);
 extern int drbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bvm, struct bio_vec *bvec);
 extern int is_valid_ar_handle(struct drbd_request *, sector_t);

diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c
@@ -1073,15 +1073,15 @@ static int drbd_fail_request_early(struct drbd_conf *mdev, int is_write)
 	return 0;
 }
 
-int drbd_make_request(struct request_queue *q, struct bio *bio)
+void drbd_make_request(struct request_queue *q, struct bio *bio)
 {
 	unsigned int s_enr, e_enr;
 	struct drbd_conf *mdev = (struct drbd_conf *) q->queuedata;
 	unsigned long start_time;
 
 	if (drbd_fail_request_early(mdev, bio_data_dir(bio) & WRITE)) {
 		bio_endio(bio, -EPERM);
-		return 0;
+		return;
 	}
 
 	start_time = jiffies;
@@ -1100,7 +1100,8 @@ int drbd_make_request(struct request_queue *q, struct bio *bio)
 
 	if (likely(s_enr == e_enr)) {
 		inc_ap_bio(mdev, 1);
-		return drbd_make_request_common(mdev, bio, start_time);
+		drbd_make_request_common(mdev, bio, start_time);
+		return;
 	}
 
 	/* can this bio be split generically?
@@ -1148,7 +1149,6 @@ int drbd_make_request(struct request_queue *q, struct bio *bio)
 
 		bio_pair_release(bp);
 	}
-	return 0;
 }
 
 /* This is called by bio_add_page().  With this function we reduce

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
@@ -514,7 +514,7 @@ static struct bio *loop_get_bio(struct loop_device *lo)
 	return bio_list_pop(&lo->lo_bio_list);
 }
 
-static int loop_make_request(struct request_queue *q, struct bio *old_bio)
+static void loop_make_request(struct request_queue *q, struct bio *old_bio)
 {
 	struct loop_device *lo = q->queuedata;
 	int rw = bio_rw(old_bio);
@@ -532,12 +532,11 @@ static int loop_make_request(struct request_queue *q, struct bio *old_bio)
 	loop_add_bio(lo, old_bio);
 	wake_up(&lo->lo_event);
 	spin_unlock_irq(&lo->lo_lock);
-	return 0;
+	return;
 
 out:
 	spin_unlock_irq(&lo->lo_lock);
 	bio_io_error(old_bio);
-	return 0;
 }
 
 struct switch_request {