Commit 152e283f authored by FUJITA Tomonori's avatar FUJITA Tomonori Committed by Jens Axboe
Browse files

block: introduce struct rq_map_data to use reserved pages 



This patch introduces struct rq_map_data to enable bio_copy_use_iov()
use reserved pages.

Currently, bio_copy_user_iov allocates bounce pages but
drivers/scsi/sg.c wants to allocate pages by itself and use
them. struct rq_map_data can be used to pass allocated pages to
bio_copy_user_iov.

The current users of bio_copy_user_iov simply passes NULL (they don't
want to use pre-allocated pages).

Signed-off-by: default avatarFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Douglas Gilbert <dougg@torque.net>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
parent a3bce90e

block/blk-map.c

+16 −10
Original line number Diff line number Diff line
@@ -41,8 +41,8 @@ static int __blk_rq_unmap_user(struct bio *bio) 
}



static int __blk_rq_map_user(struct request_queue *q, struct request *rq,

			     void __user *ubuf, unsigned int len,

			     gfp_t gfp_mask)

			     struct rq_map_data *map_data, void __user *ubuf,

			     unsigned int len, gfp_t gfp_mask)

{

	unsigned long uaddr;

	unsigned int alignment;
@@ -57,10 +57,10 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq, 
	 */

	uaddr = (unsigned long) ubuf;

	alignment = queue_dma_alignment(q) | q->dma_pad_mask;

	if (!(uaddr & alignment) && !(len & alignment))

	if (!(uaddr & alignment) && !(len & alignment) && !map_data)

		bio = bio_map_user(q, NULL, uaddr, len, reading, gfp_mask);

	else

		bio = bio_copy_user(q, uaddr, len, reading, gfp_mask);

		bio = bio_copy_user(q, map_data, uaddr, len, reading, gfp_mask);



	if (IS_ERR(bio))

		return PTR_ERR(bio);
@@ -89,6 +89,7 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq, 
 * blk_rq_map_user - map user data to a request, for REQ_TYPE_BLOCK_PC usage

 * @q:		request queue where request should be inserted

 * @rq:		request structure to fill

 * @map_data:   pointer to the rq_map_data holding pages (if necessary)

 * @ubuf:	the user buffer

 * @len:	length of user data

 * @gfp_mask:	memory allocation flags
@@ -107,7 +108,8 @@ static int __blk_rq_map_user(struct request_queue *q, struct request *rq, 
 *    unmapping.

 */

int blk_rq_map_user(struct request_queue *q, struct request *rq,

		    void __user *ubuf, unsigned long len, gfp_t gfp_mask)

		    struct rq_map_data *map_data, void __user *ubuf,

		    unsigned long len, gfp_t gfp_mask)

{

	unsigned long bytes_read = 0;

	struct bio *bio = NULL;
@@ -134,7 +136,8 @@ int blk_rq_map_user(struct request_queue *q, struct request *rq, 
		if (end - start > BIO_MAX_PAGES)

			map_len -= PAGE_SIZE;



		ret = __blk_rq_map_user(q, rq, ubuf, map_len, gfp_mask);

		ret = __blk_rq_map_user(q, rq, map_data, ubuf, map_len,

					gfp_mask);

		if (ret < 0)

			goto unmap_rq;

		if (!bio)
@@ -159,6 +162,7 @@ EXPORT_SYMBOL(blk_rq_map_user); 
 * blk_rq_map_user_iov - map user data to a request, for REQ_TYPE_BLOCK_PC usage

 * @q:		request queue where request should be inserted

 * @rq:		request to map data to

 * @map_data:   pointer to the rq_map_data holding pages (if necessary)

 * @iov:	pointer to the iovec

 * @iov_count:	number of elements in the iovec

 * @len:	I/O byte count
@@ -178,8 +182,8 @@ EXPORT_SYMBOL(blk_rq_map_user); 
 *    unmapping.

 */

int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,

			struct sg_iovec *iov, int iov_count, unsigned int len,

			gfp_t gfp_mask)

			struct rq_map_data *map_data, struct sg_iovec *iov,

			int iov_count, unsigned int len, gfp_t gfp_mask)

{

	struct bio *bio;

	int i, read = rq_data_dir(rq) == READ;
@@ -197,8 +201,9 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq, 
		}

	}



	if (unaligned || (q->dma_pad_mask & len))

		bio = bio_copy_user_iov(q, iov, iov_count, read, gfp_mask);

	if (unaligned || (q->dma_pad_mask & len) || map_data)

		bio = bio_copy_user_iov(q, map_data, iov, iov_count, read,

					gfp_mask);

	else

		bio = bio_map_user_iov(q, NULL, iov, iov_count, read, gfp_mask);
@@ -220,6 +225,7 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq, 
	rq->buffer = rq->data = NULL;

	return 0;

}

EXPORT_SYMBOL(blk_rq_map_user_iov);



/**

 * blk_rq_unmap_user - unmap a request with user data

block/bsg.c

+4 −3
Original line number Diff line number Diff line
@@ -283,8 +283,8 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, int has_write_perm) 
		next_rq->cmd_type = rq->cmd_type;



		dxferp = (void*)(unsigned long)hdr->din_xferp;

		ret =  blk_rq_map_user(q, next_rq, dxferp, hdr->din_xfer_len,

				       GFP_KERNEL);

		ret =  blk_rq_map_user(q, next_rq, NULL, dxferp,

				       hdr->din_xfer_len, GFP_KERNEL);

		if (ret)

			goto out;

	}
@@ -299,7 +299,8 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr, int has_write_perm) 
		dxfer_len = 0;



	if (dxfer_len) {

		ret = blk_rq_map_user(q, rq, dxferp, dxfer_len, GFP_KERNEL);

		ret = blk_rq_map_user(q, rq, NULL, dxferp, dxfer_len,

				      GFP_KERNEL);

		if (ret)

			goto out;

	}

block/scsi_ioctl.c

+2 −2
Original line number Diff line number Diff line
@@ -314,11 +314,11 @@ static int sg_io(struct file *file, struct request_queue *q, 
			goto out;

		}



		ret = blk_rq_map_user_iov(q, rq, iov, hdr->iovec_count,

		ret = blk_rq_map_user_iov(q, rq, NULL, iov, hdr->iovec_count,

					  hdr->dxfer_len, GFP_KERNEL);

		kfree(iov);

	} else if (hdr->dxfer_len)

		ret = blk_rq_map_user(q, rq, hdr->dxferp, hdr->dxfer_len,

		ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len,

				      GFP_KERNEL);



	if (ret)

drivers/cdrom/cdrom.c

+1 −1
Original line number Diff line number Diff line
@@ -2097,7 +2097,7 @@ static int cdrom_read_cdda_bpc(struct cdrom_device_info *cdi, __u8 __user *ubuf, 


		len = nr * CD_FRAMESIZE_RAW;



		ret = blk_rq_map_user(q, rq, ubuf, len, GFP_KERNEL);

		ret = blk_rq_map_user(q, rq, NULL, ubuf, len, GFP_KERNEL);

		if (ret)

			break;

drivers/scsi/scsi_tgt_lib.c

+1 −1
Original line number Diff line number Diff line
@@ -362,7 +362,7 @@ static int scsi_map_user_pages(struct scsi_tgt_cmd *tcmd, struct scsi_cmnd *cmd, 
	int err;



	dprintk("%lx %u\n", uaddr, len);

	err = blk_rq_map_user(q, rq, (void *)uaddr, len, GFP_KERNEL);

	err = blk_rq_map_user(q, rq, NULL, (void *)uaddr, len, GFP_KERNEL);

	if (err) {

		/*

		 * TODO: need to fixup sg_tablesize, max_segment_size,

CRA Git | Maintained and supported by SUSTech CRA and CCSE