From 2c9ecdf40af0554ee9a2b1cbbbbdbc77f90a40e1 Mon Sep 17 00:00:00 2001 From: FUJITA Tomonori Date: Mon, 16 Jul 2007 08:52:15 +0200 Subject: bsg: add bidi support bsg uses the rq->next_rq pointer for a bidi request. Signed-off-by: FUJITA Tomonori Signed-off-by: Jens Axboe --- block/bsg.c | 74 ++++++++++++++++++++++++++++++++++++++++--------------------- 1 file changed, 49 insertions(+), 25 deletions(-) (limited to 'block') diff --git a/block/bsg.c b/block/bsg.c index 5f4abc902a0..13ecc951a4c 100644 --- a/block/bsg.c +++ b/block/bsg.c @@ -95,6 +95,7 @@ struct bsg_command { struct list_head list; struct request *rq; struct bio *bio; + struct bio *bidi_bio; int err; struct sg_io_v4 hdr; struct sg_io_v4 __user *uhdr; @@ -243,16 +244,6 @@ bsg_validate_sgv4_hdr(request_queue_t *q, struct sg_io_v4 *hdr, int *rw) if (hdr->protocol || hdr->subprotocol) return -EINVAL; - /* - * looks sane, if no data then it should be fine from our POV - */ - if (!hdr->dout_xfer_len && !hdr->din_xfer_len) - return 0; - - /* not supported currently */ - if (hdr->dout_xfer_len && hdr->din_xfer_len) - return -EINVAL; - *rw = hdr->dout_xfer_len ? WRITE : READ; return 0; @@ -265,7 +256,7 @@ static struct request * bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr) { request_queue_t *q = bd->queue; - struct request *rq; + struct request *rq, *next_rq = NULL; int ret, rw = 0; /* shut up gcc */ unsigned int dxfer_len; void *dxferp = NULL; @@ -282,11 +273,30 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr) * map scatter-gather elements seperately and string them to request */ rq = blk_get_request(q, rw, GFP_KERNEL); + if (!rq) + return ERR_PTR(-ENOMEM); ret = blk_fill_sgv4_hdr_rq(q, rq, hdr, test_bit(BSG_F_WRITE_PERM, &bd->flags)); - if (ret) { - blk_put_request(rq); - return ERR_PTR(ret); + if (ret) + goto out; + + if (rw == WRITE && hdr->din_xfer_len) { + if (!test_bit(QUEUE_FLAG_BIDI, &q->queue_flags)) { + ret = -EOPNOTSUPP; + goto out; + } + + next_rq = blk_get_request(q, READ, GFP_KERNEL); + if (!next_rq) { + ret = -ENOMEM; + goto out; + } + rq->next_rq = next_rq; + + dxferp = (void*)(unsigned long)hdr->din_xferp; + ret = blk_rq_map_user(q, next_rq, dxferp, hdr->din_xfer_len); + if (ret) + goto out; } if (hdr->dout_xfer_len) { @@ -300,14 +310,17 @@ bsg_map_hdr(struct bsg_device *bd, struct sg_io_v4 *hdr) if (dxfer_len) { ret = blk_rq_map_user(q, rq, dxferp, dxfer_len); - if (ret) { - dprintk("failed map at %d\n", ret); - blk_put_request(rq); - rq = ERR_PTR(ret); - } + if (ret) + goto out; } - return rq; +out: + blk_put_request(rq); + if (next_rq) { + blk_rq_unmap_user(next_rq->bio); + blk_put_request(next_rq); + } + return ERR_PTR(ret); } /* @@ -346,6 +359,8 @@ static void bsg_add_command(struct bsg_device *bd, request_queue_t *q, */ bc->rq = rq; bc->bio = rq->bio; + if (rq->next_rq) + bc->bidi_bio = rq->next_rq->bio; bc->hdr.duration = jiffies; spin_lock_irq(&bd->lock); list_add_tail(&bc->list, &bd->busy_list); @@ -402,7 +417,7 @@ static struct bsg_command *bsg_get_done_cmd(struct bsg_device *bd) } static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr, - struct bio *bio) + struct bio *bio, struct bio *bidi_bio) { int ret = 0; @@ -431,6 +446,11 @@ static int blk_complete_sgv4_hdr_rq(struct request *rq, struct sg_io_v4 *hdr, ret = -EFAULT; } + if (rq->next_rq) { + blk_rq_unmap_user(bidi_bio); + blk_put_request(rq->next_rq); + } + blk_rq_unmap_user(bio); blk_put_request(rq); @@ -477,7 +497,8 @@ static int bsg_complete_all_commands(struct bsg_device *bd) if (IS_ERR(bc)) break; - tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio); + tret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio, + bc->bidi_bio); if (!ret) ret = tret; @@ -511,7 +532,8 @@ __bsg_read(char __user *buf, size_t count, struct bsg_device *bd, * after completing the request. so do that here, * bsg_complete_work() cannot do that for us */ - ret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio); + ret = blk_complete_sgv4_hdr_rq(bc->rq, &bc->hdr, bc->bio, + bc->bidi_bio); if (copy_to_user(buf, (char *) &bc->hdr, sizeof(bc->hdr))) ret = -EFAULT; @@ -868,7 +890,7 @@ bsg_ioctl(struct inode *inode, struct file *file, unsigned int cmd, } case SG_IO: { struct request *rq; - struct bio *bio; + struct bio *bio, *bidi_bio = NULL; struct sg_io_v4 hdr; if (copy_from_user(&hdr, uarg, sizeof(hdr))) @@ -879,8 +901,10 @@ bsg_ioctl(struct inode *inode, struct file *file, unsigned int cmd, return PTR_ERR(rq); bio = rq->bio; + if (rq->next_rq) + bidi_bio = rq->next_rq->bio; blk_execute_rq(bd->queue, NULL, rq, 0); - blk_complete_sgv4_hdr_rq(rq, &hdr, bio); + blk_complete_sgv4_hdr_rq(rq, &hdr, bio, bidi_bio); if (copy_to_user(uarg, &hdr, sizeof(hdr))) return -EFAULT; -- cgit v1.2.3