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-rw-r--r--drivers/block/ll_rw_blk.c64
-rw-r--r--drivers/block/scsi_ioctl.c34
2 files changed, 81 insertions, 17 deletions
diff --git a/drivers/block/ll_rw_blk.c b/drivers/block/ll_rw_blk.c
index 42c4f3651cf8..874e46fc3748 100644
--- a/drivers/block/ll_rw_blk.c
+++ b/drivers/block/ll_rw_blk.c
@@ -2149,6 +2149,50 @@ int blk_rq_map_user(request_queue_t *q, struct request *rq, void __user *ubuf,
EXPORT_SYMBOL(blk_rq_map_user);
/**
+ * blk_rq_map_user_iov - map user data to a request, for REQ_BLOCK_PC usage
+ * @q: request queue where request should be inserted
+ * @rq: request to map data to
+ * @iov: pointer to the iovec
+ * @iov_count: number of elements in the iovec
+ *
+ * Description:
+ * Data will be mapped directly for zero copy io, if possible. Otherwise
+ * a kernel bounce buffer is used.
+ *
+ * A matching blk_rq_unmap_user() must be issued at the end of io, while
+ * still in process context.
+ *
+ * Note: The mapped bio may need to be bounced through blk_queue_bounce()
+ * before being submitted to the device, as pages mapped may be out of
+ * reach. It's the callers responsibility to make sure this happens. The
+ * original bio must be passed back in to blk_rq_unmap_user() for proper
+ * unmapping.
+ */
+int blk_rq_map_user_iov(request_queue_t *q, struct request *rq,
+ struct sg_iovec *iov, int iov_count)
+{
+ struct bio *bio;
+
+ if (!iov || iov_count <= 0)
+ return -EINVAL;
+
+ /* we don't allow misaligned data like bio_map_user() does. If the
+ * user is using sg, they're expected to know the alignment constraints
+ * and respect them accordingly */
+ bio = bio_map_user_iov(q, NULL, iov, iov_count, rq_data_dir(rq)== READ);
+ if (IS_ERR(bio))
+ return PTR_ERR(bio);
+
+ rq->bio = rq->biotail = bio;
+ blk_rq_bio_prep(q, rq, bio);
+ rq->buffer = rq->data = NULL;
+ rq->data_len = bio->bi_size;
+ return 0;
+}
+
+EXPORT_SYMBOL(blk_rq_map_user_iov);
+
+/**
* blk_rq_unmap_user - unmap a request with user data
* @rq: request to be unmapped
* @bio: bio for the request
@@ -2207,6 +2251,19 @@ int blk_rq_map_kern(request_queue_t *q, struct request *rq, void *kbuf,
EXPORT_SYMBOL(blk_rq_map_kern);
+void blk_execute_rq_nowait(request_queue_t *q, struct gendisk *bd_disk,
+ struct request *rq, int at_head,
+ void (*done)(struct request *))
+{
+ int where = at_head ? ELEVATOR_INSERT_FRONT : ELEVATOR_INSERT_BACK;
+
+ rq->rq_disk = bd_disk;
+ rq->flags |= REQ_NOMERGE;
+ rq->end_io = done;
+ elv_add_request(q, rq, where, 1);
+ generic_unplug_device(q);
+}
+
/**
* blk_execute_rq - insert a request into queue for execution
* @q: queue to insert the request in
@@ -2224,8 +2281,6 @@ int blk_execute_rq(request_queue_t *q, struct gendisk *bd_disk,
char sense[SCSI_SENSE_BUFFERSIZE];
int err = 0;
- rq->rq_disk = bd_disk;
-
/*
* we need an extra reference to the request, so we can look at
* it after io completion
@@ -2238,11 +2293,8 @@ int blk_execute_rq(request_queue_t *q, struct gendisk *bd_disk,
rq->sense_len = 0;
}
- rq->flags |= REQ_NOMERGE;
rq->waiting = &wait;
- rq->end_io = blk_end_sync_rq;
- elv_add_request(q, rq, ELEVATOR_INSERT_BACK, 1);
- generic_unplug_device(q);
+ blk_execute_rq_nowait(q, bd_disk, rq, 0, blk_end_sync_rq);
wait_for_completion(&wait);
rq->waiting = NULL;
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