vhost currently merges regions with contiguious virtual and physical
addresses. This breaks for vhost-user since that also needs fds to
match.
Add a vhost_ops entry to compare the fds for vhost-user only.
Cc: qemu-sta...@nongnu.org
Cc: Victor Kaplansky <vict...@redhat.com>
Signed-off-by: Michael S. Tsirkin <m...@redhat.com>
---
include/hw/virtio/vhost-backend.h | 4 ++++
hw/virtio/vhost-user.c | 20 ++++++++++++++++++++
hw/virtio/vhost.c | 7 +++++++
3 files changed, 31 insertions(+)
diff --git a/include/hw/virtio/vhost-backend.h
b/include/hw/virtio/vhost-backend.h
index c59cc81..a6e5c97 100644
--- a/include/hw/virtio/vhost-backend.h
+++ b/include/hw/virtio/vhost-backend.h
@@ -70,6 +70,9 @@ typedef int (*vhost_set_vring_enable_op)(struct vhost_dev
*dev,
typedef bool (*vhost_requires_shm_log_op)(struct vhost_dev *dev);
typedef int (*vhost_migration_done_op)(struct vhost_dev *dev,
char *mac_addr);
+typedef bool (*vhost_backend_can_merge_op)(struct vhost_dev *dev,
+ uint64_t start1, uint64_t size1,
+ uint64_t start2, uint64_t size2);
typedef struct VhostOps {
VhostBackendType backend_type;
@@ -97,6 +100,7 @@ typedef struct VhostOps {
vhost_set_vring_enable_op vhost_set_vring_enable;
vhost_requires_shm_log_op vhost_requires_shm_log;
vhost_migration_done_op vhost_migration_done;
+ vhost_backend_can_merge_op vhost_backend_can_merge;
} VhostOps;
extern const VhostOps user_ops;
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index 7fde137..7ed3dd9 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -611,6 +611,25 @@ static int vhost_user_migration_done(struct vhost_dev
*dev, char* mac_addr)
return -1;
}
+static bool vhost_user_can_merge(struct vhost_dev *dev,
+ uint64_t start1, uint64_t size1,
+ uint64_t start2, uint64_t size2)
+{
+ ram_addr_t ram_addr;
+ int mfd, rfd;
+ MemoryRegion *mr;
+
+ mr = qemu_ram_addr_from_host((void *)(uintptr_t)start1, &ram_addr);
+ assert(mr);
+ mfd = qemu_get_ram_fd(ram_addr);
+
+ mr = qemu_ram_addr_from_host((void *)(uintptr_t)start2, &ram_addr);
+ assert(mr);
+ rfd = qemu_get_ram_fd(ram_addr);
+
+ return mfd == rfd;
+}
+
const VhostOps user_ops = {
.backend_type = VHOST_BACKEND_TYPE_USER,
.vhost_backend_init = vhost_user_init,
@@ -633,4 +652,5 @@ const VhostOps user_ops = {
.vhost_set_vring_enable = vhost_user_set_vring_enable,
.vhost_requires_shm_log = vhost_user_requires_shm_log,
.vhost_migration_done = vhost_user_migration_done,
+ .vhost_backend_can_merge = vhost_user_can_merge,
};
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index 72d0c9e..392d848 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -260,6 +260,13 @@ static void vhost_dev_assign_memory(struct vhost_dev *dev,
continue;
}
+ if (dev->vhost_ops->vhost_backend_can_merge &&
+ !dev->vhost_ops->vhost_backend_can_merge(dev, uaddr, size,
+ reg->userspace_addr,
+ reg->memory_size)) {
+ continue;
+ }
+
if (merged) {
--to;
assert(to >= 0);
--
MST
