virtio: de-structify virtio_block status byte
Ron Minnich points out that a struct containing a char is not always
sizeof(char); simplest to remove the structure to avoid confusion.
Cc: "ron minnich" <rminnich@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/Documentation/lguest/lguest.c b/Documentation/lguest/lguest.c
index 4c1fc65..5cd705c 100644
--- a/Documentation/lguest/lguest.c
+++ b/Documentation/lguest/lguest.c
@@ -1398,7 +1398,7 @@
struct vblk_info *vblk = dev->priv;
unsigned int head, out_num, in_num, wlen;
int ret;
- struct virtio_blk_inhdr *in;
+ u8 *in;
struct virtio_blk_outhdr *out;
struct iovec iov[dev->vq->vring.num];
off64_t off;
@@ -1416,7 +1416,7 @@
head, out_num, in_num);
out = convert(&iov[0], struct virtio_blk_outhdr);
- in = convert(&iov[out_num+in_num-1], struct virtio_blk_inhdr);
+ in = convert(&iov[out_num+in_num-1], u8);
off = out->sector * 512;
/* The block device implements "barriers", where the Guest indicates
@@ -1430,7 +1430,7 @@
* It'd be nice if we supported eject, for example, but we don't. */
if (out->type & VIRTIO_BLK_T_SCSI_CMD) {
fprintf(stderr, "Scsi commands unsupported\n");
- in->status = VIRTIO_BLK_S_UNSUPP;
+ *in = VIRTIO_BLK_S_UNSUPP;
wlen = sizeof(*in);
} else if (out->type & VIRTIO_BLK_T_OUT) {
/* Write */
@@ -1453,7 +1453,7 @@
errx(1, "Write past end %llu+%u", off, ret);
}
wlen = sizeof(*in);
- in->status = (ret >= 0 ? VIRTIO_BLK_S_OK : VIRTIO_BLK_S_IOERR);
+ *in = (ret >= 0 ? VIRTIO_BLK_S_OK : VIRTIO_BLK_S_IOERR);
} else {
/* Read */
@@ -1466,10 +1466,10 @@
verbose("READ from sector %llu: %i\n", out->sector, ret);
if (ret >= 0) {
wlen = sizeof(*in) + ret;
- in->status = VIRTIO_BLK_S_OK;
+ *in = VIRTIO_BLK_S_OK;
} else {
wlen = sizeof(*in);
- in->status = VIRTIO_BLK_S_IOERR;
+ *in = VIRTIO_BLK_S_IOERR;
}
}
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 0cfbe8c..fb283af 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -35,7 +35,7 @@
struct list_head list;
struct request *req;
struct virtio_blk_outhdr out_hdr;
- struct virtio_blk_inhdr in_hdr;
+ u8 status;
};
static void blk_done(struct virtqueue *vq)
@@ -48,7 +48,7 @@
spin_lock_irqsave(&vblk->lock, flags);
while ((vbr = vblk->vq->vq_ops->get_buf(vblk->vq, &len)) != NULL) {
int uptodate;
- switch (vbr->in_hdr.status) {
+ switch (vbr->status) {
case VIRTIO_BLK_S_OK:
uptodate = 1;
break;
@@ -101,7 +101,7 @@
sg_init_table(vblk->sg, VIRTIO_MAX_SG);
sg_set_buf(&vblk->sg[0], &vbr->out_hdr, sizeof(vbr->out_hdr));
num = blk_rq_map_sg(q, vbr->req, vblk->sg+1);
- sg_set_buf(&vblk->sg[num+1], &vbr->in_hdr, sizeof(vbr->in_hdr));
+ sg_set_buf(&vblk->sg[num+1], &vbr->status, sizeof(vbr->status));
if (rq_data_dir(vbr->req) == WRITE) {
vbr->out_hdr.type |= VIRTIO_BLK_T_OUT;
diff --git a/include/linux/virtio_blk.h b/include/linux/virtio_blk.h
index bca0b10..c75a9e8 100644
--- a/include/linux/virtio_blk.h
+++ b/include/linux/virtio_blk.h
@@ -41,13 +41,8 @@
__u64 sector;
};
+/* And this is the final byte of the write scatter-gather list. */
#define VIRTIO_BLK_S_OK 0
#define VIRTIO_BLK_S_IOERR 1
#define VIRTIO_BLK_S_UNSUPP 2
-
-/* This is the first element of the write scatter-gather list */
-struct virtio_blk_inhdr
-{
- unsigned char status;
-};
#endif /* _LINUX_VIRTIO_BLK_H */