From 152e283fdfea0cd11e297d982378b55937842dde Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Thu, 28 Aug 2008 16:17:06 +0900 Subject: [PATCH] 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 ++++++++++------- block/bsg.c | 7 +++-- block/scsi_ioctl.c | 4 +-- drivers/cdrom/cdrom.c | 2 +- drivers/scsi/scsi_tgt_lib.c | 2 +- fs/bio.c | 58 ++++++++++++++++++++++++++----------- include/linux/bio.h | 8 +++-- include/linux/blkdev.h | 12 ++++++-- 8 files changed, 80 insertions(+), 39 deletions(-) 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 diff --git a/block/bsg.c b/block/bsg.c index e7a142e9916c..56cb343c76d8 100644 --- a/block/bsg.c +++ b/block/bsg.c @@ -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; } diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c index f49d6a11a69e..c34272a348fe 100644 --- a/block/scsi_ioctl.c +++ b/block/scsi_ioctl.c @@ -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) diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c index e861d24a6d32..d47f2f80accd 100644 --- a/drivers/cdrom/cdrom.c +++ b/drivers/cdrom/cdrom.c @@ -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; diff --git a/drivers/scsi/scsi_tgt_lib.c b/drivers/scsi/scsi_tgt_lib.c index 2a4fd820d616..3117bb106b5d 100644 --- a/drivers/scsi/scsi_tgt_lib.c +++ b/drivers/scsi/scsi_tgt_lib.c @@ -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, diff --git a/fs/bio.c b/fs/bio.c index 3d2e9ad24728..a2f072647cdf 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -439,16 +439,19 @@ int bio_add_page(struct bio *bio, struct page *page, unsigned int len, struct bio_map_data { struct bio_vec *iovecs; - int nr_sgvecs; struct sg_iovec *sgvecs; + int nr_sgvecs; + int is_our_pages; }; static void bio_set_map_data(struct bio_map_data *bmd, struct bio *bio, - struct sg_iovec *iov, int iov_count) + struct sg_iovec *iov, int iov_count, + int is_our_pages) { memcpy(bmd->iovecs, bio->bi_io_vec, sizeof(struct bio_vec) * bio->bi_vcnt); memcpy(bmd->sgvecs, iov, sizeof(struct sg_iovec) * iov_count); bmd->nr_sgvecs = iov_count; + bmd->is_our_pages = is_our_pages; bio->bi_private = bmd; } @@ -483,7 +486,8 @@ static struct bio_map_data *bio_alloc_map_data(int nr_segs, int iov_count, } static int __bio_copy_iov(struct bio *bio, struct bio_vec *iovecs, - struct sg_iovec *iov, int iov_count, int uncopy) + struct sg_iovec *iov, int iov_count, int uncopy, + int do_free_page) { int ret = 0, i; struct bio_vec *bvec; @@ -526,7 +530,7 @@ static int __bio_copy_iov(struct bio *bio, struct bio_vec *iovecs, } } - if (uncopy) + if (do_free_page) __free_page(bvec->bv_page); } @@ -545,7 +549,8 @@ int bio_uncopy_user(struct bio *bio) struct bio_map_data *bmd = bio->bi_private; int ret; - ret = __bio_copy_iov(bio, bmd->iovecs, bmd->sgvecs, bmd->nr_sgvecs, 1); + ret = __bio_copy_iov(bio, bmd->iovecs, bmd->sgvecs, bmd->nr_sgvecs, 1, + bmd->is_our_pages); bio_free_map_data(bmd); bio_put(bio); @@ -555,6 +560,7 @@ int bio_uncopy_user(struct bio *bio) /** * bio_copy_user_iov - copy user data to bio * @q: destination block queue + * @map_data: pointer to the rq_map_data holding pages (if necessary) * @iov: the iovec. * @iov_count: number of elements in the iovec * @write_to_vm: bool indicating writing to pages or not @@ -564,8 +570,10 @@ int bio_uncopy_user(struct bio *bio) * to/from kernel pages as necessary. Must be paired with * call bio_uncopy_user() on io completion. */ -struct bio *bio_copy_user_iov(struct request_queue *q, struct sg_iovec *iov, - int iov_count, int write_to_vm, gfp_t gfp_mask) +struct bio *bio_copy_user_iov(struct request_queue *q, + struct rq_map_data *map_data, + struct sg_iovec *iov, int iov_count, + int write_to_vm, gfp_t gfp_mask) { struct bio_map_data *bmd; struct bio_vec *bvec; @@ -600,13 +608,26 @@ struct bio *bio_copy_user_iov(struct request_queue *q, struct sg_iovec *iov, bio->bi_rw |= (!write_to_vm << BIO_RW); ret = 0; + i = 0; while (len) { - unsigned int bytes = PAGE_SIZE; + unsigned int bytes; + + if (map_data) + bytes = 1U << (PAGE_SHIFT + map_data->page_order); + else + bytes = PAGE_SIZE; if (bytes > len) bytes = len; - page = alloc_page(q->bounce_gfp | gfp_mask); + if (map_data) { + if (i == map_data->nr_entries) { + ret = -ENOMEM; + break; + } + page = map_data->pages[i++]; + } else + page = alloc_page(q->bounce_gfp | gfp_mask); if (!page) { ret = -ENOMEM; break; @@ -625,16 +646,17 @@ struct bio *bio_copy_user_iov(struct request_queue *q, struct sg_iovec *iov, * success */ if (!write_to_vm) { - ret = __bio_copy_iov(bio, bio->bi_io_vec, iov, iov_count, 0); + ret = __bio_copy_iov(bio, bio->bi_io_vec, iov, iov_count, 0, 0); if (ret) goto cleanup; } - bio_set_map_data(bmd, bio, iov, iov_count); + bio_set_map_data(bmd, bio, iov, iov_count, map_data ? 0 : 1); return bio; cleanup: - bio_for_each_segment(bvec, bio, i) - __free_page(bvec->bv_page); + if (!map_data) + bio_for_each_segment(bvec, bio, i) + __free_page(bvec->bv_page); bio_put(bio); out_bmd: @@ -645,6 +667,7 @@ out_bmd: /** * bio_copy_user - copy user data to bio * @q: destination block queue + * @map_data: pointer to the rq_map_data holding pages (if necessary) * @uaddr: start of user address * @len: length in bytes * @write_to_vm: bool indicating writing to pages or not @@ -654,15 +677,16 @@ out_bmd: * to/from kernel pages as necessary. Must be paired with * call bio_uncopy_user() on io completion. */ -struct bio *bio_copy_user(struct request_queue *q, unsigned long uaddr, - unsigned int len, int write_to_vm, gfp_t gfp_mask) +struct bio *bio_copy_user(struct request_queue *q, struct rq_map_data *map_data, + unsigned long uaddr, unsigned int len, + int write_to_vm, gfp_t gfp_mask) { struct sg_iovec iov; iov.iov_base = (void __user *)uaddr; iov.iov_len = len; - return bio_copy_user_iov(q, &iov, 1, write_to_vm, gfp_mask); + return bio_copy_user_iov(q, map_data, &iov, 1, write_to_vm, gfp_mask); } static struct bio *__bio_map_user_iov(struct request_queue *q, @@ -1028,7 +1052,7 @@ struct bio *bio_copy_kern(struct request_queue *q, void *data, unsigned int len, bio->bi_private = bmd; bio->bi_end_io = bio_copy_kern_endio; - bio_set_map_data(bmd, bio, &iov, 1); + bio_set_map_data(bmd, bio, &iov, 1, 1); return bio; cleanup: bio_for_each_segment(bvec, bio, i) diff --git a/include/linux/bio.h b/include/linux/bio.h index 200b185c3e83..bc386cd5e996 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -327,6 +327,7 @@ extern int bio_get_nr_vecs(struct block_device *); extern struct bio *bio_map_user(struct request_queue *, struct block_device *, unsigned long, unsigned int, int, gfp_t); struct sg_iovec; +struct rq_map_data; extern struct bio *bio_map_user_iov(struct request_queue *, struct block_device *, struct sg_iovec *, int, int, gfp_t); @@ -337,9 +338,10 @@ extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int, gfp_t, int); extern void bio_set_pages_dirty(struct bio *bio); extern void bio_check_pages_dirty(struct bio *bio); -extern struct bio *bio_copy_user(struct request_queue *, unsigned long, - unsigned int, int, gfp_t); -extern struct bio *bio_copy_user_iov(struct request_queue *, struct sg_iovec *, +extern struct bio *bio_copy_user(struct request_queue *, struct rq_map_data *, + unsigned long, unsigned int, int, gfp_t); +extern struct bio *bio_copy_user_iov(struct request_queue *, + struct rq_map_data *, struct sg_iovec *, int, int, gfp_t); extern int bio_uncopy_user(struct bio *); void zero_fill_bio(struct bio *bio); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 00e388d0e221..358ac423ed2f 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -642,6 +642,12 @@ static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) } #endif /* CONFIG_MMU */ +struct rq_map_data { + struct page **pages; + int page_order; + int nr_entries; +}; + struct req_iterator { int i; struct bio *bio; @@ -711,11 +717,13 @@ extern void __blk_run_queue(struct request_queue *); extern void blk_run_queue(struct request_queue *); extern void blk_start_queueing(struct request_queue *); extern int blk_rq_map_user(struct request_queue *, struct request *, - void __user *, unsigned long, gfp_t); + struct rq_map_data *, void __user *, unsigned long, + gfp_t); extern int blk_rq_unmap_user(struct bio *); extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); extern int blk_rq_map_user_iov(struct request_queue *, struct request *, - struct sg_iovec *, int, unsigned int, gfp_t); + struct rq_map_data *, struct sg_iovec *, int, + unsigned int, gfp_t); extern int blk_execute_rq(struct request_queue *, struct gendisk *, struct request *, int); extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,