Add support for posted writes on remote devices
Signed-off-by: Elena Ufimtseva <elena.ufimts...@oracle.com>
Signed-off-by: John G Johnson <john.g.john...@oracle.com>
Signed-off-by: Jagannathan Raman <jag.ra...@oracle.com>
---
hw/vfio/common.c | 10 +++-
hw/vfio/pci.c | 9 +++-
hw/vfio/pci.h | 1 +
hw/vfio/user-protocol.h | 12 +++++
hw/vfio/user.c | 109 ++++++++++++++++++++++++++++++++++++++++++
hw/vfio/user.h | 1 +
include/hw/vfio/vfio-common.h | 7 +--
7 files changed, 143 insertions(+), 6 deletions(-)
diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 87400b3..87cd1d1 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -214,6 +214,7 @@ void vfio_region_write(void *opaque, hwaddr addr,
uint32_t dword;
uint64_t qword;
} buf;
+ bool post = region->post_wr;
int ret;
switch (size) {
@@ -234,7 +235,11 @@ void vfio_region_write(void *opaque, hwaddr addr,
break;
}
- ret = VDEV_REGION_WRITE(vbasedev, region->nr, addr, size, &buf);
+ /* read-after-write hazard if guest can directly access region */
+ if (region->nr_mmaps) {
+ post = false;
+ }
+ ret = VDEV_REGION_WRITE(vbasedev, region->nr, addr, size, &buf, post);
if (ret != size) {
const char *err = ret < 0 ? strerror(-ret) : "short write";
@@ -1587,6 +1592,7 @@ int vfio_region_setup(Object *obj, VFIODevice *vbasedev,
VFIORegion *region,
region->size = info->size;
region->fd_offset = info->offset;
region->nr = index;
+ region->post_wr = false;
if (vbasedev->regfds != NULL) {
region->fd = vbasedev->regfds[index];
} else {
@@ -2721,7 +2727,7 @@ static int vfio_io_region_read(VFIODevice *vbasedev,
uint8_t index, off_t off,
}
static int vfio_io_region_write(VFIODevice *vbasedev, uint8_t index, off_t off,
- uint32_t size, void *data)
+ uint32_t size, void *data, bool post)
{
struct vfio_region_info *info = vbasedev->regions[index];
int ret;
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 2e0e41d..027f9d5 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -51,7 +51,7 @@
(size), (data))
#define VDEV_CONFIG_WRITE(vbasedev, off, size, data) \
VDEV_REGION_WRITE((vbasedev), VFIO_PCI_CONFIG_REGION_INDEX, (off), \
- (size), (data))
+ (size), (data), false)
#define TYPE_VFIO_PCI_NOHOTPLUG "vfio-pci-nohotplug"
@@ -1704,6 +1704,9 @@ static void vfio_bar_prepare(VFIOPCIDevice *vdev, int nr)
bar->type = pci_bar & (bar->ioport ? ~PCI_BASE_ADDRESS_IO_MASK :
~PCI_BASE_ADDRESS_MEM_MASK);
bar->size = bar->region.size;
+
+ /* IO regions are sync, memory can be async */
+ bar->region.post_wr = (bar->ioport == 0);
}
static void vfio_bars_prepare(VFIOPCIDevice *vdev)
@@ -3494,6 +3497,9 @@ static void vfio_user_pci_realize(PCIDevice *pdev, Error
**errp)
if (udev->send_queued) {
proxy->flags |= VFIO_PROXY_FORCE_QUEUED;
}
+ if (udev->no_post) {
+ proxy->flags |= VFIO_PROXY_NO_POST;
+ }
vfio_user_validate_version(proxy, &err);
if (err != NULL) {
@@ -3540,6 +3546,7 @@ static void vfio_user_instance_finalize(Object *obj)
static Property vfio_user_pci_dev_properties[] = {
DEFINE_PROP_STRING("socket", VFIOUserPCIDevice, sock_name),
DEFINE_PROP_BOOL("x-send-queued", VFIOUserPCIDevice, send_queued, false),
+ DEFINE_PROP_BOOL("x-no-posted-writes", VFIOUserPCIDevice, no_post, false),
DEFINE_PROP_END_OF_LIST(),
};
diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
index c47d2f8..ec17f2e 100644
--- a/hw/vfio/pci.h
+++ b/hw/vfio/pci.h
@@ -196,6 +196,7 @@ struct VFIOUserPCIDevice {
VFIOPCIDevice device;
char *sock_name;
bool send_queued; /* all sends are queued */
+ bool no_post; /* all regions write are sync */
};
/* Use uin32_t for vendor & device so PCI_ANY_ID expands and cannot match hw */
diff --git a/hw/vfio/user-protocol.h b/hw/vfio/user-protocol.h
index a1b64fe..124340c 100644
--- a/hw/vfio/user-protocol.h
+++ b/hw/vfio/user-protocol.h
@@ -140,4 +140,16 @@ typedef struct {
uint64_t offset;
} VFIOUserRegionInfo;
+/*
+ * VFIO_USER_REGION_READ
+ * VFIO_USER_REGION_WRITE
+ */
+typedef struct {
+ VFIOUserHdr hdr;
+ uint64_t offset;
+ uint32_t region;
+ uint32_t count;
+ char data[];
+} VFIOUserRegionRW;
+
#endif /* VFIO_USER_PROTOCOL_H */
diff --git a/hw/vfio/user.c b/hw/vfio/user.c
index 69b0fed..1453bb5 100644
--- a/hw/vfio/user.c
+++ b/hw/vfio/user.c
@@ -57,6 +57,8 @@ static void vfio_user_cb(void *opaque);
static void vfio_user_request(void *opaque);
static int vfio_user_send_queued(VFIOProxy *proxy, VFIOUserMsg *msg);
+static void vfio_user_send_async(VFIOProxy *proxy, VFIOUserHdr *hdr,
+ VFIOUserFDs *fds);
static void vfio_user_send_wait(VFIOProxy *proxy, VFIOUserHdr *hdr,
VFIOUserFDs *fds, int rsize, bool nobql);
static void vfio_user_request_msg(VFIOUserHdr *hdr, uint16_t cmd,
@@ -618,6 +620,33 @@ static int vfio_user_send_queued(VFIOProxy *proxy,
VFIOUserMsg *msg)
return 0;
}
+/*
+ * async send - msg can be queued, but will be freed when sent
+ */
+static void vfio_user_send_async(VFIOProxy *proxy, VFIOUserHdr *hdr,
+ VFIOUserFDs *fds)
+{
+ VFIOUserMsg *msg;
+ int ret;
+
+ if (!(hdr->flags & (VFIO_USER_NO_REPLY | VFIO_USER_REPLY))) {
+ error_printf("vfio_user_send_async on sync message\n");
+ return;
+ }
+
+ QEMU_LOCK_GUARD(&proxy->lock);
+
+ msg = vfio_user_getmsg(proxy, hdr, fds);
+ msg->id = hdr->id;
+ msg->rsize = 0;
+ msg->type = VFIO_MSG_ASYNC;
+
+ ret = vfio_user_send_queued(proxy, msg);
+ if (ret < 0) {
+ vfio_user_recycle(proxy, msg);
+ }
+}
+
static void vfio_user_send_wait(VFIOProxy *proxy, VFIOUserHdr *hdr,
VFIOUserFDs *fds, int rsize, bool nobql)
{
@@ -1135,6 +1164,70 @@ static int vfio_user_get_region_info(VFIOProxy *proxy,
return 0;
}
+static int vfio_user_region_read(VFIOProxy *proxy, uint8_t index, off_t offset,
+ uint32_t count, void *data)
+{
+ g_autofree VFIOUserRegionRW *msgp = NULL;
+ int size = sizeof(*msgp) + count;
+
+ if (count > proxy->max_xfer_size) {
+ return -EINVAL;
+ }
+
+ msgp = g_malloc0(size);
+ vfio_user_request_msg(&msgp->hdr, VFIO_USER_REGION_READ, sizeof(*msgp), 0);
+ msgp->offset = offset;
+ msgp->region = index;
+ msgp->count = count;
+
+ vfio_user_send_wait(proxy, &msgp->hdr, NULL, size, false);
+ if (msgp->hdr.flags & VFIO_USER_ERROR) {
+ return -msgp->hdr.error_reply;
+ } else if (msgp->count > count) {
+ return -E2BIG;
+ } else {
+ memcpy(data, &msgp->data, msgp->count);
+ }
+
+ return msgp->count;
+}
+
+static int vfio_user_region_write(VFIOProxy *proxy, uint8_t index, off_t
offset,
+ uint32_t count, void *data, bool post)
+{
+ VFIOUserRegionRW *msgp = NULL;
+ int flags = post ? VFIO_USER_NO_REPLY : 0;
+ int size = sizeof(*msgp) + count;
+ int ret;
+
+ if (count > proxy->max_xfer_size) {
+ return -EINVAL;
+ }
+
+ msgp = g_malloc0(size);
+ vfio_user_request_msg(&msgp->hdr, VFIO_USER_REGION_WRITE, size, flags);
+ msgp->offset = offset;
+ msgp->region = index;
+ msgp->count = count;
+ memcpy(&msgp->data, data, count);
+
+ /* async send will free msg after it's sent */
+ if (post && !(proxy->flags & VFIO_PROXY_NO_POST)) {
+ vfio_user_send_async(proxy, &msgp->hdr, NULL);
+ return count;
+ }
+
+ vfio_user_send_wait(proxy, &msgp->hdr, NULL, 0, false);
+ if (msgp->hdr.flags & VFIO_USER_ERROR) {
+ ret = -msgp->hdr.error_reply;
+ } else {
+ ret = count;
+ }
+
+ g_free(msgp);
+ return ret;
+}
+
/*
* Socket-based io_ops
@@ -1184,8 +1277,24 @@ static int vfio_user_io_get_region_info(VFIODevice
*vbasedev,
return 0;
}
+static int vfio_user_io_region_read(VFIODevice *vbasedev, uint8_t index,
+ off_t off, uint32_t size, void *data)
+{
+ return vfio_user_region_read(vbasedev->proxy, index, off, size, data);
+}
+
+static int vfio_user_io_region_write(VFIODevice *vbasedev, uint8_t index,
+ off_t off, unsigned size, void *data,
+ bool post)
+{
+ return vfio_user_region_write(vbasedev->proxy, index, off, size, data,
+ post);
+}
+
VFIODevIO vfio_dev_io_sock = {
.get_info = vfio_user_io_get_info,
.get_region_info = vfio_user_io_get_region_info,
+ .region_read = vfio_user_io_region_read,
+ .region_write = vfio_user_io_region_write,
};
diff --git a/hw/vfio/user.h b/hw/vfio/user.h
index 2547cf6..359a029 100644
--- a/hw/vfio/user.h
+++ b/hw/vfio/user.h
@@ -84,6 +84,7 @@ typedef struct VFIOProxy {
/* VFIOProxy flags */
#define VFIO_PROXY_CLIENT 0x1
#define VFIO_PROXY_FORCE_QUEUED 0x4
+#define VFIO_PROXY_NO_POST 0x8
VFIOProxy *vfio_user_connect_dev(SocketAddress *addr, Error **errp);
void vfio_user_disconnect(VFIOProxy *proxy);
diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index 3406e6a..6324132 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -57,6 +57,7 @@ typedef struct VFIORegion {
VFIOMmap *mmaps;
uint8_t nr; /* cache the region number for debug */
int fd; /* fd to mmap() region */
+ bool post_wr; /* writes can be posted */
} VFIORegion;
typedef struct VFIOMigration {
@@ -180,7 +181,7 @@ struct VFIODevIO {
int (*region_read)(VFIODevice *vdev, uint8_t nr, off_t off, uint32_t size,
void *data);
int (*region_write)(VFIODevice *vdev, uint8_t nr, off_t off, uint32_t size,
- void *data);
+ void *data, bool post);
};
#define VDEV_GET_INFO(vdev, info) \
@@ -193,8 +194,8 @@ struct VFIODevIO {
((vdev)->io_ops->set_irqs((vdev), (irqs)))
#define VDEV_REGION_READ(vdev, nr, off, size, data) \
((vdev)->io_ops->region_read((vdev), (nr), (off), (size), (data)))
-#define VDEV_REGION_WRITE(vdev, nr, off, size, data) \
- ((vdev)->io_ops->region_write((vdev), (nr), (off), (size), (data)))
+#define VDEV_REGION_WRITE(vdev, nr, off, size, data, post) \
+ ((vdev)->io_ops->region_write((vdev), (nr), (off), (size), (data), (post)))
struct VFIOContIO {
int (*dma_map)(VFIOContainer *container,
--
1.8.3.1
