Commit 8f8e57ab authored by K. Y. Srinivasan's avatar K. Y. Srinivasan Committed by Greg Kroah-Hartman
Browse files

Staging: hv: Get rid of the forward declaration for blkvsc_do_request() 



Get rid of the forward declaration for blkvsc_do_request() by moving the
code around.

Signed-off-by: default avatarK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: default avatarHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: default avatarAbhishek Kane <v-abkane@microsoft.com>
Signed-off-by: default avatarHank Janssen <hjanssen@microsoft.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 2c77407a

drivers/staging/hv/blkvsc_drv.c

+193 −177
Original line number Diff line number Diff line
@@ -118,6 +118,12 @@ static const struct hv_guid g_blk_device_type = { 
	}

};



/*

 * There is a circular dependency involving blkvsc_request_completion()

 * and blkvsc_do_request().

 */

static void blkvsc_request_completion(struct hv_storvsc_request *request);



static int blk_vsc_on_device_add(struct hv_device *device,

				void *additional_info)

{
@@ -947,12 +953,196 @@ static int blkvsc_do_inquiry(struct block_device_context *blkdev) 
	return 0;

}





/*

 * We break the request into 1 or more blkvsc_requests and submit

 * them.  If we cant submit them all, we put them on the

 * pending_list. The blkvsc_request() will work on the pending_list.

 */

static int blkvsc_do_request(struct block_device_context *blkdev,

			     struct request *req)

{

	struct bio *bio = NULL;

	struct bio_vec *bvec = NULL;

	struct bio_vec *prev_bvec = NULL;

	struct blkvsc_request *blkvsc_req = NULL;

	struct blkvsc_request *tmp;

	int databuf_idx = 0;

	int seg_idx = 0;

	sector_t start_sector;

	unsigned long num_sectors = 0;

	int ret = 0;

	int pending = 0;

	struct blkvsc_request_group *group = NULL;



	DPRINT_DBG(BLKVSC_DRV, "blkdev %p req %p sect %lu\n", blkdev, req,

		  (unsigned long)blk_rq_pos(req));



	/* Create a group to tie req to list of blkvsc_reqs */

	group = kmem_cache_zalloc(blkdev->request_pool, GFP_ATOMIC);

	if (!group)

		return -ENOMEM;



	INIT_LIST_HEAD(&group->blkvsc_req_list);

	group->outstanding = group->status = 0;



	start_sector = blk_rq_pos(req);



	/* foreach bio in the request */

	if (req->bio) {

		for (bio = req->bio; bio; bio = bio->bi_next) {

			/*

			 * Map this bio into an existing or new storvsc request

			 */

			bio_for_each_segment(bvec, bio, seg_idx) {

				DPRINT_DBG(BLKVSC_DRV, "bio_for_each_segment() "

					   "- req %p bio %p bvec %p seg_idx %d "

					   "databuf_idx %d\n", req, bio, bvec,

					   seg_idx, databuf_idx);



				/* Get a new storvsc request */

				/* 1st-time */

				if ((!blkvsc_req) ||

				    (databuf_idx >= MAX_MULTIPAGE_BUFFER_COUNT)

				    /* hole at the begin of page */

				    || (bvec->bv_offset != 0) ||

				    /* hold at the end of page */

				    (prev_bvec &&

				     (prev_bvec->bv_len != PAGE_SIZE))) {

					/* submit the prev one */

					if (blkvsc_req) {

						blkvsc_req->sector_start =

						start_sector;

						sector_div(

						blkvsc_req->sector_start,

						(blkdev->sector_size >> 9));



						blkvsc_req->sector_count =

						num_sectors /

						(blkdev->sector_size >> 9);

						blkvsc_init_rw(blkvsc_req);

					}



					/*

					 * Create new blkvsc_req to represent

					 * the current bvec

					 */

					blkvsc_req =

					kmem_cache_zalloc(

					blkdev->request_pool, GFP_ATOMIC);

					if (!blkvsc_req) {

						/* free up everything */

						list_for_each_entry_safe(

							blkvsc_req, tmp,

							&group->blkvsc_req_list,

							req_entry) {

							list_del(

							&blkvsc_req->req_entry);

							kmem_cache_free(

							blkdev->request_pool,

							blkvsc_req);

						}



						kmem_cache_free(

						blkdev->request_pool, group);

						return -ENOMEM;

					}



					memset(blkvsc_req, 0,

					       sizeof(struct blkvsc_request));



					blkvsc_req->dev = blkdev;

					blkvsc_req->req = req;

					blkvsc_req->request.

					data_buffer.offset

					= bvec->bv_offset;

					blkvsc_req->request.

					data_buffer.len = 0;



					/* Add to the group */

					blkvsc_req->group = group;

					blkvsc_req->group->outstanding++;

					list_add_tail(&blkvsc_req->req_entry,

					&blkvsc_req->group->blkvsc_req_list);



					start_sector += num_sectors;

					num_sectors = 0;

					databuf_idx = 0;

				}



				/*

				 * Add the curr bvec/segment to the curr

				 * blkvsc_req

				 */

				blkvsc_req->request.data_buffer.

					pfn_array[databuf_idx]

						= page_to_pfn(bvec->bv_page);

				blkvsc_req->request.data_buffer.len

					+= bvec->bv_len;



				prev_bvec = bvec;



				databuf_idx++;

				num_sectors += bvec->bv_len >> 9;



			} /* bio_for_each_segment */



		} /* rq_for_each_bio */

	}



	/* Handle the last one */

	if (blkvsc_req) {

		DPRINT_DBG(BLKVSC_DRV, "blkdev %p req %p group %p count %d\n",

			   blkdev, req, blkvsc_req->group,

			   blkvsc_req->group->outstanding);



		blkvsc_req->sector_start = start_sector;

		sector_div(blkvsc_req->sector_start,

			   (blkdev->sector_size >> 9));



		blkvsc_req->sector_count = num_sectors /

					   (blkdev->sector_size >> 9);



		blkvsc_init_rw(blkvsc_req);

	}



	list_for_each_entry(blkvsc_req, &group->blkvsc_req_list, req_entry) {

		if (pending) {

			DPRINT_DBG(BLKVSC_DRV, "adding blkvsc_req to "

				   "pending_list - blkvsc_req %p start_sect %lu"

				   " sect_count %ld (%lu %ld)\n", blkvsc_req,

				   (unsigned long)blkvsc_req->sector_start,

				   blkvsc_req->sector_count,

				   (unsigned long)start_sector,

				   (unsigned long)num_sectors);



			list_add_tail(&blkvsc_req->pend_entry,

				      &blkdev->pending_list);

		} else {

			ret = blkvsc_submit_request(blkvsc_req,

						    blkvsc_request_completion);

			if (ret == -1) {

				pending = 1;

				list_add_tail(&blkvsc_req->pend_entry,

					      &blkdev->pending_list);

			}



			DPRINT_DBG(BLKVSC_DRV, "submitted blkvsc_req %p "

				   "start_sect %lu sect_count %ld (%lu %ld) "

				   "ret %d\n", blkvsc_req,

				   (unsigned long)blkvsc_req->sector_start,

				   blkvsc_req->sector_count,

				   (unsigned long)start_sector,

				   num_sectors, ret);

		}

	}



	return pending;

}



/* Static decl */

static int blkvsc_probe(struct device *dev);

static void blkvsc_request(struct request_queue *queue);

static void blkvsc_request_completion(struct hv_storvsc_request *request);

static int blkvsc_do_request(struct block_device_context *blkdev,

			     struct request *req);

static int blkvsc_do_pending_reqs(struct block_device_context *blkdev);



static int blkvsc_ringbuffer_size = BLKVSC_RING_BUFFER_SIZE;
@@ -1207,180 +1397,6 @@ static int blkvsc_probe(struct device *device) 
	return ret;

}



/*

 * We break the request into 1 or more blkvsc_requests and submit

 * them.  If we can't submit them all, we put them on the

 * pending_list. The blkvsc_request() will work on the pending_list.

 */

static int blkvsc_do_request(struct block_device_context *blkdev,

			     struct request *req)

{

	struct bio *bio = NULL;

	struct bio_vec *bvec = NULL;

	struct bio_vec *prev_bvec = NULL;

	struct blkvsc_request *blkvsc_req = NULL;

	struct blkvsc_request *tmp;

	int databuf_idx = 0;

	int seg_idx = 0;

	sector_t start_sector;

	unsigned long num_sectors = 0;

	int ret = 0;

	int pending = 0;

	struct blkvsc_request_group *group = NULL;



	DPRINT_DBG(BLKVSC_DRV, "blkdev %p req %p sect %lu\n", blkdev, req,

		  (unsigned long)blk_rq_pos(req));



	/* Create a group to tie req to list of blkvsc_reqs */

	group = kmem_cache_zalloc(blkdev->request_pool, GFP_ATOMIC);

	if (!group)

		return -ENOMEM;



	INIT_LIST_HEAD(&group->blkvsc_req_list);

	group->outstanding = group->status = 0;



	start_sector = blk_rq_pos(req);



	/* foreach bio in the request */

	if (req->bio) {

		for (bio = req->bio; bio; bio = bio->bi_next) {

			/*

			 * Map this bio into an existing or new storvsc request

			 */

			bio_for_each_segment(bvec, bio, seg_idx) {

				DPRINT_DBG(BLKVSC_DRV, "bio_for_each_segment() "

					   "- req %p bio %p bvec %p seg_idx %d "

					   "databuf_idx %d\n", req, bio, bvec,

					   seg_idx, databuf_idx);



				/* Get a new storvsc request */

				/* 1st-time */

				if ((!blkvsc_req) ||

				    (databuf_idx >= MAX_MULTIPAGE_BUFFER_COUNT)

				    /* hole at the begin of page */

				    || (bvec->bv_offset != 0) ||

				    /* hold at the end of page */

				    (prev_bvec &&

				     (prev_bvec->bv_len != PAGE_SIZE))) {

					/* submit the prev one */

					if (blkvsc_req) {

						blkvsc_req->sector_start = start_sector;

						sector_div(blkvsc_req->sector_start, (blkdev->sector_size >> 9));



						blkvsc_req->sector_count = num_sectors / (blkdev->sector_size >> 9);

						blkvsc_init_rw(blkvsc_req);

					}



					/*

					 * Create new blkvsc_req to represent

					 * the current bvec

					 */

					blkvsc_req =

					kmem_cache_zalloc(

					blkdev->request_pool, GFP_ATOMIC);

					if (!blkvsc_req) {

						/* free up everything */

						list_for_each_entry_safe(

							blkvsc_req, tmp,

							&group->blkvsc_req_list,

							req_entry) {

							list_del(&blkvsc_req->req_entry);

							kmem_cache_free(blkdev->request_pool, blkvsc_req);

						}



						kmem_cache_free(blkdev->request_pool, group);

						return -ENOMEM;

					}



					memset(blkvsc_req, 0,

					       sizeof(struct blkvsc_request));



					blkvsc_req->dev = blkdev;

					blkvsc_req->req = req;

					blkvsc_req->request.

					data_buffer.offset

					= bvec->bv_offset;

					blkvsc_req->request.

					data_buffer.len = 0;



					/* Add to the group */

					blkvsc_req->group = group;

					blkvsc_req->group->outstanding++;

					list_add_tail(&blkvsc_req->req_entry,

						&blkvsc_req->group->blkvsc_req_list);



					start_sector += num_sectors;

					num_sectors = 0;

					databuf_idx = 0;

				}



				/* Add the curr bvec/segment to the curr blkvsc_req */

				blkvsc_req->request.data_buffer.

					pfn_array[databuf_idx]

						= page_to_pfn(bvec->bv_page);

				blkvsc_req->request.data_buffer.len

					+= bvec->bv_len;



				prev_bvec = bvec;



				databuf_idx++;

				num_sectors += bvec->bv_len >> 9;



			} /* bio_for_each_segment */



		} /* rq_for_each_bio */

	}



	/* Handle the last one */

	if (blkvsc_req) {

		DPRINT_DBG(BLKVSC_DRV, "blkdev %p req %p group %p count %d\n",

			   blkdev, req, blkvsc_req->group,

			   blkvsc_req->group->outstanding);



		blkvsc_req->sector_start = start_sector;

		sector_div(blkvsc_req->sector_start,

			   (blkdev->sector_size >> 9));



		blkvsc_req->sector_count = num_sectors /

					   (blkdev->sector_size >> 9);



		blkvsc_init_rw(blkvsc_req);

	}



	list_for_each_entry(blkvsc_req, &group->blkvsc_req_list, req_entry) {

		if (pending) {

			DPRINT_DBG(BLKVSC_DRV, "adding blkvsc_req to "

				   "pending_list - blkvsc_req %p start_sect %lu"

				   " sect_count %ld (%lu %ld)\n", blkvsc_req,

				   (unsigned long)blkvsc_req->sector_start,

				   blkvsc_req->sector_count,

				   (unsigned long)start_sector,

				   (unsigned long)num_sectors);



			list_add_tail(&blkvsc_req->pend_entry,

				      &blkdev->pending_list);

		} else {

			ret = blkvsc_submit_request(blkvsc_req,

						    blkvsc_request_completion);

			if (ret == -1) {

				pending = 1;

				list_add_tail(&blkvsc_req->pend_entry,

					      &blkdev->pending_list);

			}



			DPRINT_DBG(BLKVSC_DRV, "submitted blkvsc_req %p "

				   "start_sect %lu sect_count %ld (%lu %ld) "

				   "ret %d\n", blkvsc_req,

				   (unsigned long)blkvsc_req->sector_start,

				   blkvsc_req->sector_count,

				   (unsigned long)start_sector,

				   num_sectors, ret);

		}

	}



	return pending;

}



static void blkvsc_request_completion(struct hv_storvsc_request *request)

{

	struct blkvsc_request *blkvsc_req =