From 152e283fdfea0cd11e297d982378b55937842dde Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Thu, 28 Aug 2008 16:17:06 +0900 Subject: 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: FUJITA Tomonori Cc: Jens Axboe Cc: Douglas Gilbert Cc: Mike Christie Cc: James Bottomley Signed-off-by: Jens Axboe --- block/blk-map.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) (limited to 'block/blk-map.c') diff --git a/block/blk-map.c b/block/blk-map.c index ac21b7397e15..dad6a2907835 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -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 -- cgit v1.2.3-58-ga151