Replace the repeated pattern:
be_ipl() ? x : bswapN(x)
with helpers that conditionally byte-swap based on the virtio transport
endianness.
While only the 16-bit helper is used immediately, the 32-bit and 64-bit
variants are added here for later use.
Signed-off-by: Zhuoying Cai <[email protected]>
Reviewed-by: Jason J. Herne <[email protected]>
Reviewed-by: Matthew Rosato <[email protected]>
---
pc-bios/s390-ccw/virtio.c | 27 +++++++++++++++++++++------
pc-bios/s390-ccw/virtio.h | 4 ++++
2 files changed, 25 insertions(+), 6 deletions(-)
diff --git a/pc-bios/s390-ccw/virtio.c b/pc-bios/s390-ccw/virtio.c
index a0d249db24..037c00a3e1 100644
--- a/pc-bios/s390-ccw/virtio.c
+++ b/pc-bios/s390-ccw/virtio.c
@@ -97,7 +97,7 @@ void vring_init(VRing *vr, VqInfo *info)
vr->avail->idx = 0;
/* We're running with interrupts off anyways, so don't bother */
- vr->used->flags = be_ipl() ? VRING_USED_F_NO_NOTIFY :
bswap16(VRING_USED_F_NO_NOTIFY);
+ vr->used->flags = virtio_tswap16(VRING_USED_F_NO_NOTIFY);
vr->used->idx = 0;
vr->used_idx = 0;
vr->next_idx = 0;
@@ -140,6 +140,22 @@ bool be_ipl(void)
}
}
+/* Conditionally byte-swap between virtio-endian and s390x native big-endian.
*/
+uint16_t virtio_tswap16(uint16_t x)
+{
+ return be_ipl() ? x : bswap16(x);
+}
+
+uint32_t virtio_tswap32(uint32_t x)
+{
+ return be_ipl() ? x : bswap32(x);
+}
+
+uint64_t virtio_tswap64(uint64_t x)
+{
+ return be_ipl() ? x : bswap64(x);
+}
+
/*
* Format the virtio ring descriptor endianness
* Return the available index increment in the appropriate endianness
@@ -156,12 +172,11 @@ void vring_send_buf(VRing *vr, void *p, int len, int
flags)
{
uint16_t avail_idx;
- avail_idx = be_ipl() ? vr->avail->idx : bswap16(vr->avail->idx);
+ avail_idx = virtio_tswap16(vr->avail->idx);
/* For follow-up chains we need to keep the first entry point */
if (!(flags & VRING_HIDDEN_IS_CHAIN)) {
- vr->avail->ring[avail_idx % vr->num] = be_ipl() ? vr->next_idx :
-
bswap16(vr->next_idx);
+ vr->avail->ring[avail_idx % vr->num] = virtio_tswap16(vr->next_idx);
}
vr->desc[vr->next_idx].addr = (unsigned long)p;
@@ -179,7 +194,7 @@ void vring_send_buf(VRing *vr, void *p, int len, int flags)
/* Chains only have a single ID */
if (!(flags & VRING_DESC_F_NEXT)) {
avail_idx++;
- vr->avail->idx = be_ipl() ? avail_idx : bswap16(avail_idx);
+ vr->avail->idx = virtio_tswap16(avail_idx);
}
}
@@ -187,7 +202,7 @@ int vr_poll(VRing *vr)
{
uint16_t used_idx;
- used_idx = be_ipl() ? vr->used->idx : bswap16(vr->used->idx);
+ used_idx = virtio_tswap16(vr->used->idx);
if (used_idx == vr->used_idx) {
vring_notify(vr);
yield();
diff --git a/pc-bios/s390-ccw/virtio.h b/pc-bios/s390-ccw/virtio.h
index aa307025e0..645dc288b1 100644
--- a/pc-bios/s390-ccw/virtio.h
+++ b/pc-bios/s390-ccw/virtio.h
@@ -287,6 +287,10 @@ int virtio_run(VDev *vdev, int vqid, VirtioCmd *cmd);
int virtio_reset(VDev *vdev);
int virtio_setup_ccw(VDev *vdev);
+uint16_t virtio_tswap16(uint16_t x);
+uint32_t virtio_tswap32(uint32_t x);
+uint64_t virtio_tswap64(uint64_t x);
+
/* virtio-net.c */
int virtio_net_init(void *mac_addr);
void virtio_net_deinit(void);
--
2.55.0
