* [Qemu-devel] [PATCH v2] virtio dataplane: adapt dataplane for virtio Version 1
@ 2015-08-26 13:24 Pierre Morel
2015-08-26 14:09 ` Greg Kurz
` (3 more replies)
0 siblings, 4 replies; 5+ messages in thread
From: Pierre Morel @ 2015-08-26 13:24 UTC (permalink / raw)
To: qemu-devel; +Cc: cornelia.huck, mst, pmorel, stefanha, gkurz
Let dataplane allocate different region for the desc/avail/used
ring regions.
Signed-off-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Acked-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Tested-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
---
hw/virtio/dataplane/vring.c | 48 ++++++++++++++++++++++++++-----------
include/hw/virtio/dataplane/vring.h | 4 +++-
2 files changed, 37 insertions(+), 15 deletions(-)
diff --git a/hw/virtio/dataplane/vring.c b/hw/virtio/dataplane/vring.c
index 07fd69c..ad86be5 100644
--- a/hw/virtio/dataplane/vring.c
+++ b/hw/virtio/dataplane/vring.c
@@ -65,24 +65,34 @@ static void vring_unmap(void *buffer, bool is_write)
}
/* Map the guest's vring to host memory */
+
+#define MAP_VRING_DESCRIPTOR(d) { \
+ hwaddr addr; \
+ hwaddr size; \
+ void *ptr; \
+ \
+ addr = virtio_queue_get_##d##_addr(vdev, n); \
+ size = virtio_queue_get_##d## _size(vdev, n); \
+ ptr = vring_map(&vring->mr_##d, addr, size, true); \
+ if (!ptr) { \
+ error_report("Failed to map vring "#d" " \
+ "addr %#" HWADDR_PRIx " size %" HWADDR_PRIu, \
+ addr, size); \
+ goto out_err_##d; \
+ } \
+ vr->d = ptr; \
+ }
+
bool vring_setup(Vring *vring, VirtIODevice *vdev, int n)
{
- hwaddr vring_addr = virtio_queue_get_ring_addr(vdev, n);
- hwaddr vring_size = virtio_queue_get_ring_size(vdev, n);
- void *vring_ptr;
+ struct vring *vr = &vring->vr;
vring->broken = false;
+ vr->num = virtio_queue_get_num(vdev, n);
- vring_ptr = vring_map(&vring->mr, vring_addr, vring_size, true);
- if (!vring_ptr) {
- error_report("Failed to map vring "
- "addr %#" HWADDR_PRIx " size %" HWADDR_PRIu,
- vring_addr, vring_size);
- vring->broken = true;
- return false;
- }
-
- vring_init(&vring->vr, virtio_queue_get_num(vdev, n), vring_ptr, 4096);
+ MAP_VRING_DESCRIPTOR(desc);
+ MAP_VRING_DESCRIPTOR(avail);
+ MAP_VRING_DESCRIPTOR(used);
vring->last_avail_idx = virtio_queue_get_last_avail_idx(vdev, n);
vring->last_used_idx = vring_get_used_idx(vdev, vring);
@@ -92,6 +102,14 @@ bool vring_setup(Vring *vring, VirtIODevice *vdev, int n)
trace_vring_setup(virtio_queue_get_ring_addr(vdev, n),
vring->vr.desc, vring->vr.avail, vring->vr.used);
return true;
+
+out_err_used:
+ memory_region_unref(vring->mr_avail);
+out_err_avail:
+ memory_region_unref(vring->mr_desc);
+out_err_desc:
+ vring->broken = true;
+ return false;
}
void vring_teardown(Vring *vring, VirtIODevice *vdev, int n)
@@ -99,7 +117,9 @@ void vring_teardown(Vring *vring, VirtIODevice *vdev, int n)
virtio_queue_set_last_avail_idx(vdev, n, vring->last_avail_idx);
virtio_queue_invalidate_signalled_used(vdev, n);
- memory_region_unref(vring->mr);
+ memory_region_unref(vring->mr_desc);
+ memory_region_unref(vring->mr_avail);
+ memory_region_unref(vring->mr_used);
}
/* Disable guest->host notifies */
diff --git a/include/hw/virtio/dataplane/vring.h b/include/hw/virtio/dataplane/vring.h
index 8d97db9..a596e4c 100644
--- a/include/hw/virtio/dataplane/vring.h
+++ b/include/hw/virtio/dataplane/vring.h
@@ -22,7 +22,9 @@
#include "hw/virtio/virtio.h"
typedef struct {
- MemoryRegion *mr; /* memory region containing the vring */
+ MemoryRegion *mr_desc; /* memory region for the vring desc */
+ MemoryRegion *mr_avail; /* memory region for the vring avail */
+ MemoryRegion *mr_used; /* memory region for the vring used */
struct vring vr; /* virtqueue vring mapped to host memory */
uint16_t last_avail_idx; /* last processed avail ring index */
uint16_t last_used_idx; /* last processed used ring index */
--
2.3.0
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [Qemu-devel] [PATCH v2] virtio dataplane: adapt dataplane for virtio Version 1
2015-08-26 13:24 [Qemu-devel] [PATCH v2] virtio dataplane: adapt dataplane for virtio Version 1 Pierre Morel
@ 2015-08-26 14:09 ` Greg Kurz
2015-08-26 14:57 ` Cornelia Huck
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Greg Kurz @ 2015-08-26 14:09 UTC (permalink / raw)
To: stefanha; +Cc: cornelia.huck, Pierre Morel, qemu-devel, mst
On Wed, 26 Aug 2015 15:24:42 +0200
Pierre Morel <pmorel@linux.vnet.ibm.com> wrote:
> Let dataplane allocate different region for the desc/avail/used
> ring regions.
>
> Signed-off-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
> Acked-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Stefan,
In case SoB is more appropriate, here it is:
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Cheers.
--
Greg
> Tested-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
> ---
> hw/virtio/dataplane/vring.c | 48 ++++++++++++++++++++++++++-----------
> include/hw/virtio/dataplane/vring.h | 4 +++-
> 2 files changed, 37 insertions(+), 15 deletions(-)
>
> diff --git a/hw/virtio/dataplane/vring.c b/hw/virtio/dataplane/vring.c
> index 07fd69c..ad86be5 100644
> --- a/hw/virtio/dataplane/vring.c
> +++ b/hw/virtio/dataplane/vring.c
> @@ -65,24 +65,34 @@ static void vring_unmap(void *buffer, bool is_write)
> }
>
> /* Map the guest's vring to host memory */
> +
> +#define MAP_VRING_DESCRIPTOR(d) { \
> + hwaddr addr; \
> + hwaddr size; \
> + void *ptr; \
> + \
> + addr = virtio_queue_get_##d##_addr(vdev, n); \
> + size = virtio_queue_get_##d## _size(vdev, n); \
> + ptr = vring_map(&vring->mr_##d, addr, size, true); \
> + if (!ptr) { \
> + error_report("Failed to map vring "#d" " \
> + "addr %#" HWADDR_PRIx " size %" HWADDR_PRIu, \
> + addr, size); \
> + goto out_err_##d; \
> + } \
> + vr->d = ptr; \
> + }
> +
> bool vring_setup(Vring *vring, VirtIODevice *vdev, int n)
> {
> - hwaddr vring_addr = virtio_queue_get_ring_addr(vdev, n);
> - hwaddr vring_size = virtio_queue_get_ring_size(vdev, n);
> - void *vring_ptr;
> + struct vring *vr = &vring->vr;
>
> vring->broken = false;
> + vr->num = virtio_queue_get_num(vdev, n);
>
> - vring_ptr = vring_map(&vring->mr, vring_addr, vring_size, true);
> - if (!vring_ptr) {
> - error_report("Failed to map vring "
> - "addr %#" HWADDR_PRIx " size %" HWADDR_PRIu,
> - vring_addr, vring_size);
> - vring->broken = true;
> - return false;
> - }
> -
> - vring_init(&vring->vr, virtio_queue_get_num(vdev, n), vring_ptr, 4096);
> + MAP_VRING_DESCRIPTOR(desc);
> + MAP_VRING_DESCRIPTOR(avail);
> + MAP_VRING_DESCRIPTOR(used);
>
> vring->last_avail_idx = virtio_queue_get_last_avail_idx(vdev, n);
> vring->last_used_idx = vring_get_used_idx(vdev, vring);
> @@ -92,6 +102,14 @@ bool vring_setup(Vring *vring, VirtIODevice *vdev, int n)
> trace_vring_setup(virtio_queue_get_ring_addr(vdev, n),
> vring->vr.desc, vring->vr.avail, vring->vr.used);
> return true;
> +
> +out_err_used:
> + memory_region_unref(vring->mr_avail);
> +out_err_avail:
> + memory_region_unref(vring->mr_desc);
> +out_err_desc:
> + vring->broken = true;
> + return false;
> }
>
> void vring_teardown(Vring *vring, VirtIODevice *vdev, int n)
> @@ -99,7 +117,9 @@ void vring_teardown(Vring *vring, VirtIODevice *vdev, int n)
> virtio_queue_set_last_avail_idx(vdev, n, vring->last_avail_idx);
> virtio_queue_invalidate_signalled_used(vdev, n);
>
> - memory_region_unref(vring->mr);
> + memory_region_unref(vring->mr_desc);
> + memory_region_unref(vring->mr_avail);
> + memory_region_unref(vring->mr_used);
> }
>
> /* Disable guest->host notifies */
> diff --git a/include/hw/virtio/dataplane/vring.h b/include/hw/virtio/dataplane/vring.h
> index 8d97db9..a596e4c 100644
> --- a/include/hw/virtio/dataplane/vring.h
> +++ b/include/hw/virtio/dataplane/vring.h
> @@ -22,7 +22,9 @@
> #include "hw/virtio/virtio.h"
>
> typedef struct {
> - MemoryRegion *mr; /* memory region containing the vring */
> + MemoryRegion *mr_desc; /* memory region for the vring desc */
> + MemoryRegion *mr_avail; /* memory region for the vring avail */
> + MemoryRegion *mr_used; /* memory region for the vring used */
> struct vring vr; /* virtqueue vring mapped to host memory */
> uint16_t last_avail_idx; /* last processed avail ring index */
> uint16_t last_used_idx; /* last processed used ring index */
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [Qemu-devel] [PATCH v2] virtio dataplane: adapt dataplane for virtio Version 1
2015-08-26 13:24 [Qemu-devel] [PATCH v2] virtio dataplane: adapt dataplane for virtio Version 1 Pierre Morel
2015-08-26 14:09 ` Greg Kurz
@ 2015-08-26 14:57 ` Cornelia Huck
2015-08-27 11:14 ` Michael S. Tsirkin
2015-09-01 14:08 ` Stefan Hajnoczi
3 siblings, 0 replies; 5+ messages in thread
From: Cornelia Huck @ 2015-08-26 14:57 UTC (permalink / raw)
To: Pierre Morel; +Cc: mst, qemu-devel, stefanha, gkurz
On Wed, 26 Aug 2015 15:24:42 +0200
Pierre Morel <pmorel@linux.vnet.ibm.com> wrote:
> Let dataplane allocate different region for the desc/avail/used
s/region/regions/
> ring regions.
>
> Signed-off-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
> Acked-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
> Tested-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
> ---
> hw/virtio/dataplane/vring.c | 48 ++++++++++++++++++++++++++-----------
> include/hw/virtio/dataplane/vring.h | 4 +++-
> 2 files changed, 37 insertions(+), 15 deletions(-)
>
> diff --git a/hw/virtio/dataplane/vring.c b/hw/virtio/dataplane/vring.c
> index 07fd69c..ad86be5 100644
> --- a/hw/virtio/dataplane/vring.c
> +++ b/hw/virtio/dataplane/vring.c
> @@ -65,24 +65,34 @@ static void vring_unmap(void *buffer, bool is_write)
> }
>
> /* Map the guest's vring to host memory */
> +
> +#define MAP_VRING_DESCRIPTOR(d) { \
> + hwaddr addr; \
> + hwaddr size; \
> + void *ptr; \
> + \
> + addr = virtio_queue_get_##d##_addr(vdev, n); \
> + size = virtio_queue_get_##d## _size(vdev, n); \
Inconsistent spacing (but probably can be fixed when applying).
> + ptr = vring_map(&vring->mr_##d, addr, size, true); \
> + if (!ptr) { \
> + error_report("Failed to map vring "#d" " \
> + "addr %#" HWADDR_PRIx " size %" HWADDR_PRIu, \
> + addr, size); \
> + goto out_err_##d; \
> + } \
> + vr->d = ptr; \
> + }
> +
> bool vring_setup(Vring *vring, VirtIODevice *vdev, int n)
> {
> - hwaddr vring_addr = virtio_queue_get_ring_addr(vdev, n);
> - hwaddr vring_size = virtio_queue_get_ring_size(vdev, n);
> - void *vring_ptr;
> + struct vring *vr = &vring->vr;
>
> vring->broken = false;
> + vr->num = virtio_queue_get_num(vdev, n);
>
> - vring_ptr = vring_map(&vring->mr, vring_addr, vring_size, true);
> - if (!vring_ptr) {
> - error_report("Failed to map vring "
> - "addr %#" HWADDR_PRIx " size %" HWADDR_PRIu,
> - vring_addr, vring_size);
> - vring->broken = true;
> - return false;
> - }
> -
> - vring_init(&vring->vr, virtio_queue_get_num(vdev, n), vring_ptr, 4096);
> + MAP_VRING_DESCRIPTOR(desc);
> + MAP_VRING_DESCRIPTOR(avail);
> + MAP_VRING_DESCRIPTOR(used);
>
> vring->last_avail_idx = virtio_queue_get_last_avail_idx(vdev, n);
> vring->last_used_idx = vring_get_used_idx(vdev, vring);
> @@ -92,6 +102,14 @@ bool vring_setup(Vring *vring, VirtIODevice *vdev, int n)
> trace_vring_setup(virtio_queue_get_ring_addr(vdev, n),
> vring->vr.desc, vring->vr.avail, vring->vr.used);
> return true;
> +
> +out_err_used:
> + memory_region_unref(vring->mr_avail);
> +out_err_avail:
> + memory_region_unref(vring->mr_desc);
> +out_err_desc:
> + vring->broken = true;
> + return false;
My only worry is that this might be a bit hard to parse as the gotos
are hidden in the macro. But in the end, both this and the original
version are basically fine.
> }
>
> void vring_teardown(Vring *vring, VirtIODevice *vdev, int n)
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [Qemu-devel] [PATCH v2] virtio dataplane: adapt dataplane for virtio Version 1
2015-08-26 13:24 [Qemu-devel] [PATCH v2] virtio dataplane: adapt dataplane for virtio Version 1 Pierre Morel
2015-08-26 14:09 ` Greg Kurz
2015-08-26 14:57 ` Cornelia Huck
@ 2015-08-27 11:14 ` Michael S. Tsirkin
2015-09-01 14:08 ` Stefan Hajnoczi
3 siblings, 0 replies; 5+ messages in thread
From: Michael S. Tsirkin @ 2015-08-27 11:14 UTC (permalink / raw)
To: Pierre Morel; +Cc: cornelia.huck, qemu-devel, stefanha, gkurz
On Wed, Aug 26, 2015 at 03:24:42PM +0200, Pierre Morel wrote:
> Let dataplane allocate different region for the desc/avail/used
> ring regions.
>
> Signed-off-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
> Acked-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
> Tested-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Also need to Cc stable on this.
> ---
> hw/virtio/dataplane/vring.c | 48 ++++++++++++++++++++++++++-----------
> include/hw/virtio/dataplane/vring.h | 4 +++-
> 2 files changed, 37 insertions(+), 15 deletions(-)
>
> diff --git a/hw/virtio/dataplane/vring.c b/hw/virtio/dataplane/vring.c
> index 07fd69c..ad86be5 100644
> --- a/hw/virtio/dataplane/vring.c
> +++ b/hw/virtio/dataplane/vring.c
> @@ -65,24 +65,34 @@ static void vring_unmap(void *buffer, bool is_write)
> }
>
> /* Map the guest's vring to host memory */
> +
> +#define MAP_VRING_DESCRIPTOR(d) { \
> + hwaddr addr; \
> + hwaddr size; \
> + void *ptr; \
> + \
> + addr = virtio_queue_get_##d##_addr(vdev, n); \
> + size = virtio_queue_get_##d## _size(vdev, n); \
> + ptr = vring_map(&vring->mr_##d, addr, size, true); \
> + if (!ptr) { \
> + error_report("Failed to map vring "#d" " \
> + "addr %#" HWADDR_PRIx " size %" HWADDR_PRIu, \
> + addr, size); \
> + goto out_err_##d; \
> + } \
> + vr->d = ptr; \
> + }
> +
> bool vring_setup(Vring *vring, VirtIODevice *vdev, int n)
> {
> - hwaddr vring_addr = virtio_queue_get_ring_addr(vdev, n);
> - hwaddr vring_size = virtio_queue_get_ring_size(vdev, n);
> - void *vring_ptr;
> + struct vring *vr = &vring->vr;
>
> vring->broken = false;
> + vr->num = virtio_queue_get_num(vdev, n);
>
> - vring_ptr = vring_map(&vring->mr, vring_addr, vring_size, true);
> - if (!vring_ptr) {
> - error_report("Failed to map vring "
> - "addr %#" HWADDR_PRIx " size %" HWADDR_PRIu,
> - vring_addr, vring_size);
> - vring->broken = true;
> - return false;
> - }
> -
> - vring_init(&vring->vr, virtio_queue_get_num(vdev, n), vring_ptr, 4096);
> + MAP_VRING_DESCRIPTOR(desc);
> + MAP_VRING_DESCRIPTOR(avail);
> + MAP_VRING_DESCRIPTOR(used);
>
> vring->last_avail_idx = virtio_queue_get_last_avail_idx(vdev, n);
> vring->last_used_idx = vring_get_used_idx(vdev, vring);
> @@ -92,6 +102,14 @@ bool vring_setup(Vring *vring, VirtIODevice *vdev, int n)
> trace_vring_setup(virtio_queue_get_ring_addr(vdev, n),
> vring->vr.desc, vring->vr.avail, vring->vr.used);
> return true;
> +
> +out_err_used:
> + memory_region_unref(vring->mr_avail);
> +out_err_avail:
> + memory_region_unref(vring->mr_desc);
> +out_err_desc:
> + vring->broken = true;
> + return false;
> }
>
> void vring_teardown(Vring *vring, VirtIODevice *vdev, int n)
> @@ -99,7 +117,9 @@ void vring_teardown(Vring *vring, VirtIODevice *vdev, int n)
> virtio_queue_set_last_avail_idx(vdev, n, vring->last_avail_idx);
> virtio_queue_invalidate_signalled_used(vdev, n);
>
> - memory_region_unref(vring->mr);
> + memory_region_unref(vring->mr_desc);
> + memory_region_unref(vring->mr_avail);
> + memory_region_unref(vring->mr_used);
> }
>
> /* Disable guest->host notifies */
> diff --git a/include/hw/virtio/dataplane/vring.h b/include/hw/virtio/dataplane/vring.h
> index 8d97db9..a596e4c 100644
> --- a/include/hw/virtio/dataplane/vring.h
> +++ b/include/hw/virtio/dataplane/vring.h
> @@ -22,7 +22,9 @@
> #include "hw/virtio/virtio.h"
>
> typedef struct {
> - MemoryRegion *mr; /* memory region containing the vring */
> + MemoryRegion *mr_desc; /* memory region for the vring desc */
> + MemoryRegion *mr_avail; /* memory region for the vring avail */
> + MemoryRegion *mr_used; /* memory region for the vring used */
> struct vring vr; /* virtqueue vring mapped to host memory */
> uint16_t last_avail_idx; /* last processed avail ring index */
> uint16_t last_used_idx; /* last processed used ring index */
> --
> 2.3.0
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [Qemu-devel] [PATCH v2] virtio dataplane: adapt dataplane for virtio Version 1
2015-08-26 13:24 [Qemu-devel] [PATCH v2] virtio dataplane: adapt dataplane for virtio Version 1 Pierre Morel
` (2 preceding siblings ...)
2015-08-27 11:14 ` Michael S. Tsirkin
@ 2015-09-01 14:08 ` Stefan Hajnoczi
3 siblings, 0 replies; 5+ messages in thread
From: Stefan Hajnoczi @ 2015-09-01 14:08 UTC (permalink / raw)
To: Pierre Morel; +Cc: cornelia.huck, mst, qemu-devel, gkurz
On Wed, Aug 26, 2015 at 03:24:42PM +0200, Pierre Morel wrote:
> diff --git a/hw/virtio/dataplane/vring.c b/hw/virtio/dataplane/vring.c
> index 07fd69c..ad86be5 100644
> --- a/hw/virtio/dataplane/vring.c
> +++ b/hw/virtio/dataplane/vring.c
> @@ -65,24 +65,34 @@ static void vring_unmap(void *buffer, bool is_write)
> }
>
> /* Map the guest's vring to host memory */
> +
> +#define MAP_VRING_DESCRIPTOR(d) { \
> + hwaddr addr; \
> + hwaddr size; \
> + void *ptr; \
> + \
> + addr = virtio_queue_get_##d##_addr(vdev, n); \
> + size = virtio_queue_get_##d## _size(vdev, n); \
> + ptr = vring_map(&vring->mr_##d, addr, size, true); \
> + if (!ptr) { \
> + error_report("Failed to map vring "#d" " \
> + "addr %#" HWADDR_PRIx " size %" HWADDR_PRIu, \
> + addr, size); \
> + goto out_err_##d; \
> + } \
> + vr->d = ptr; \
> + }
Not a fan of the macro, IMO it just obfuscates the code.
Also, normally do ... while (0) is used for statement-like macros to
keep it a single statement instead of a compound statement (where the
trailing semicolon would break if, while, etc).
> +
> bool vring_setup(Vring *vring, VirtIODevice *vdev, int n)
> {
> - hwaddr vring_addr = virtio_queue_get_ring_addr(vdev, n);
> - hwaddr vring_size = virtio_queue_get_ring_size(vdev, n);
> - void *vring_ptr;
> + struct vring *vr = &vring->vr;
>
> vring->broken = false;
> + vr->num = virtio_queue_get_num(vdev, n);
>
> - vring_ptr = vring_map(&vring->mr, vring_addr, vring_size, true);
> - if (!vring_ptr) {
> - error_report("Failed to map vring "
> - "addr %#" HWADDR_PRIx " size %" HWADDR_PRIu,
> - vring_addr, vring_size);
> - vring->broken = true;
> - return false;
> - }
> -
> - vring_init(&vring->vr, virtio_queue_get_num(vdev, n), vring_ptr, 4096);
> + MAP_VRING_DESCRIPTOR(desc);
> + MAP_VRING_DESCRIPTOR(avail);
> + MAP_VRING_DESCRIPTOR(used);
This doesn't take VIRTIO_RING_F_EVENT_IDX into account, where we access
beyond the end of the rings. Please check that code path and map the
memory.
^ permalink raw reply [flat|nested] 5+ messages in thread
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2015-08-26 13:24 [Qemu-devel] [PATCH v2] virtio dataplane: adapt dataplane for virtio Version 1 Pierre Morel
2015-08-26 14:09 ` Greg Kurz
2015-08-26 14:57 ` Cornelia Huck
2015-08-27 11:14 ` Michael S. Tsirkin
2015-09-01 14:08 ` Stefan Hajnoczi
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