Force remote process to use DMA r/w messages instead
of directly mapping guest memory.
Signed-off-by: John G Johnson <john.g.johnson@oracle.com>
Signed-off-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>
Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
---
hw/vfio/user.h | 1 +
hw/vfio/user-pci.c | 5 +++++
hw/vfio/user.c | 2 +-
3 files changed, 7 insertions(+), 1 deletion(-)
diff --git a/hw/vfio/user.h b/hw/vfio/user.h
index b89e5ca..fe0115b 100644
--- a/hw/vfio/user.h
+++ b/hw/vfio/user.h
@@ -83,6 +83,7 @@ typedef struct VFIOUserProxy {
/* VFIOProxy flags */
#define VFIO_PROXY_CLIENT 0x1
+#define VFIO_PROXY_NO_MMAP 0x2
#define VFIO_PROXY_FORCE_QUEUED 0x4
#define VFIO_PROXY_NO_POST 0x8
diff --git a/hw/vfio/user-pci.c b/hw/vfio/user-pci.c
index a0aa320..bf84d7c 100644
--- a/hw/vfio/user-pci.c
+++ b/hw/vfio/user-pci.c
@@ -40,6 +40,7 @@ OBJECT_DECLARE_SIMPLE_TYPE(VFIOUserPCIDevice, VFIO_USER_PCI)
struct VFIOUserPCIDevice {
VFIOPCIDevice device;
char *sock_name;
+ bool no_direct_dma; /* disable shared mem for DMA */
bool send_queued; /* all sends are queued */
bool no_post; /* all regions write are sync */
};
@@ -160,6 +161,9 @@ static void vfio_user_pci_realize(PCIDevice *pdev, Error **errp)
vbasedev->proxy = proxy;
vfio_user_set_handler(vbasedev, vfio_user_pci_process_req, vdev);
+ if (udev->no_direct_dma) {
+ proxy->flags |= VFIO_PROXY_NO_MMAP;
+ }
if (udev->send_queued) {
proxy->flags |= VFIO_PROXY_FORCE_QUEUED;
}
@@ -269,6 +273,7 @@ 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("no-direct-dma", VFIOUserPCIDevice, no_direct_dma, false),
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/user.c b/hw/vfio/user.c
index fe6e476..0a7b354 100644
--- a/hw/vfio/user.c
+++ b/hw/vfio/user.c
@@ -1806,7 +1806,7 @@ static int vfio_user_io_dma_map(VFIOContainer *container, MemoryRegion *mr,
* map->vaddr enters as a QEMU process address
* make it either a file offset for mapped areas or 0
*/
- if (fd != -1) {
+ if (fd != -1 && (container->proxy->flags & VFIO_PROXY_NO_MMAP) == 0) {
void *addr = (void *)(uintptr_t)map->vaddr;
map->vaddr = qemu_ram_block_host_offset(mr->ram_block, addr);
--
1.9.4