Register a vmstate post_load handler to call IOMMU_IOAS_CHANGE_PROCESS and
update the virtual address of all DMA mappings after CPR.
Signed-off-by: Steve Sistare <steven.sist...@oracle.com>
---
backends/iommufd.c | 81 +++++++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 80 insertions(+), 1 deletion(-)
diff --git a/backends/iommufd.c b/backends/iommufd.c
index 86fd9db..2e72b6f 100644
--- a/backends/iommufd.c
+++ b/backends/iommufd.c
@@ -17,7 +17,9 @@
#include "qom/object_interfaces.h"
#include "qemu/error-report.h"
#include "migration/cpr.h"
+#include "migration/vmstate.h"
#include "monitor/monitor.h"
+#include "exec/ramblock.h"
#include "trace.h"
#include <sys/ioctl.h>
#include <linux/iommufd.h>
@@ -81,6 +83,83 @@ bool iommufd_change_process_capable(IOMMUFDBackend *be)
return (errno != ENOTTY);
}
+static int iommufd_change_process(IOMMUFDBackend *be,
+ struct iommu_ioas_change_process *args)
+{
+ int ret, fd = be->fd;
+
+ ret = ioctl(fd, IOMMU_IOAS_CHANGE_PROCESS, args);
+ if (ret) {
+ ret = -errno;
+ error_report("IOMMU_IOAS_CHANGE_PROCESS failed: %m");
+ }
+ return ret;
+}
+
+static int count_umap(RAMBlock *rb, void *opaque)
+{
+ if (qemu_ram_is_migratable(rb)) {
+ (*(int *)opaque)++;
+ }
+ return 0;
+}
+
+static int fill_umap(RAMBlock *rb, void *opaque)
+{
+ if (qemu_ram_is_migratable(rb)) {
+ struct iommu_ioas_change_process *args = opaque;
+ struct iommu_ioas_userspace_map *umap = (void *)args->umap;
+ int i = args->n_umap++;
+
+ assert(rb->host_old && rb->host);
+ umap[i].addr_old = (__u64)rb->host_old;
+ umap[i].addr_new = (__u64)rb->host;
+ umap[i].size = rb->max_length;
+ }
+ return 0;
+}
+
+static int cmp_umap(const void *elem1, const void *elem2)
+{
+ const struct iommu_ioas_userspace_map *e1 = elem1;
+ const struct iommu_ioas_userspace_map *e2 = elem2;
+
+ return (e1->addr_old < e2->addr_old) ? -1 :
+ (e1->addr_old > e2->addr_old);
+}
+
+static int iommufd_cpr_post_load(void *opaque, int version_id)
+{
+ IOMMUFDBackend *be = opaque;
+ struct iommu_ioas_change_process args = {
+ .size = sizeof(args),
+ .flags = 0,
+ .n_umap = 0,
+ .umap = 0,
+ };
+ int n = 0;
+ g_autofree struct iommu_ioas_userspace_map *umap = NULL;
+
+ RCU_READ_LOCK_GUARD();
+ qemu_ram_foreach_block(count_umap, &n);
+ umap = g_malloc_n(n, sizeof(*umap));
+ args.umap = (__u64)umap;
+ qemu_ram_foreach_block(fill_umap, &args);
+ qsort(umap, args.n_umap, sizeof(*umap), cmp_umap);
+ return iommufd_change_process(be, &args);
+}
+
+static const VMStateDescription iommufd_cpr_vmstate = {
+ .name = "iommufd",
+ .version_id = 0,
+ .minimum_version_id = 0,
+ .post_load = iommufd_cpr_post_load,
+ .needed = cpr_needed_for_reuse,
+ .fields = (VMStateField[]) {
+ VMSTATE_END_OF_LIST()
+ }
+};
+
bool iommufd_backend_connect(IOMMUFDBackend *be, const char *name, Error
**errp)
{
int fd;
@@ -100,7 +179,7 @@ bool iommufd_backend_connect(IOMMUFDBackend *be, const char
*name, Error **errp)
be->fd = fd;
}
be->users++;
-
+ vmstate_register(NULL, -1, &iommufd_cpr_vmstate, be);
trace_iommufd_backend_connect(be->fd, be->owned, be->users);
return true;
}
--
1.8.3.1
