diff options
| author | James Bottomley <James.Bottomley@SteelEye.com> | 2005-06-20 14:06:52 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@suse.de> | 2005-06-20 14:06:52 +0200 |
| commit | f1970baf6d74e03bd32072ab453f2fc01bc1b8d3 (patch) | |
| tree | 559898cdf83bd0f93b8a72248c6423a6548fb604 /drivers/block/scsi_ioctl.c | |
| parent | dd1cab95f356f1395278633565f198463cf6bd24 (diff) | |
| download | lwn-f1970baf6d74e03bd32072ab453f2fc01bc1b8d3.tar.gz lwn-f1970baf6d74e03bd32072ab453f2fc01bc1b8d3.zip | |
[PATCH] Add scatter-gather support for the block layer SG_IO
Signed-off-by: Jens Axboe <axboe@suse.de>
Diffstat (limited to 'drivers/block/scsi_ioctl.c')
| -rw-r--r-- | drivers/block/scsi_ioctl.c | 34 |
1 files changed, 23 insertions, 11 deletions
diff --git a/drivers/block/scsi_ioctl.c b/drivers/block/scsi_ioctl.c index 93c4ca874be3..09a7e73a0812 100644 --- a/drivers/block/scsi_ioctl.c +++ b/drivers/block/scsi_ioctl.c @@ -231,17 +231,11 @@ static int sg_io(struct file *file, request_queue_t *q, if (verify_command(file, cmd)) return -EPERM; - /* - * we'll do that later - */ - if (hdr->iovec_count) - return -EOPNOTSUPP; - if (hdr->dxfer_len > (q->max_sectors << 9)) return -EIO; reading = writing = 0; - if (hdr->dxfer_len) { + if (hdr->dxfer_len) switch (hdr->dxfer_direction) { default: return -EINVAL; @@ -261,11 +255,29 @@ static int sg_io(struct file *file, request_queue_t *q, if (!rq) return -ENOMEM; - if (reading || writing) { - ret = blk_rq_map_user(q, rq, hdr->dxferp, hdr->dxfer_len); - if (ret) + if (hdr->iovec_count) { + const int size = sizeof(struct sg_iovec) * hdr->iovec_count; + struct sg_iovec *iov; + + iov = kmalloc(size, GFP_KERNEL); + if (!iov) { + ret = -ENOMEM; goto out; - } + } + + if (copy_from_user(iov, hdr->dxferp, size)) { + kfree(iov); + ret = -EFAULT; + goto out; + } + + ret = blk_rq_map_user_iov(q, rq, iov, hdr->iovec_count); + kfree(iov); + } else if (hdr->dxfer_len) + ret = blk_rq_map_user(q, rq, hdr->dxferp, hdr->dxfer_len); + + if (ret) + goto out; /* * fill in request structure |