net/virtio: use memseg contig walk instead of iteration

Reduce dependency on internal details of EAL memory subsystem, and
simplify code.

Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Tested-by: Santosh Shukla <santosh.shukla@caviumnetworks.com>
Tested-by: Hemant Agrawal <hemant.agrawal@nxp.com>
Tested-by: Gowrishankar Muthukrishnan <gowrishankar.m@linux.vnet.ibm.com>

diff --git a/drivers/net/virtio/virtio_user/vhost_kernel.c b/drivers/net/virtio/virtio_user/vhost_kernel.c
index 1711ead..93d7efe 100644 (file)
--- a/drivers/net/virtio/virtio_user/vhost_kernel.c
+++ b/drivers/net/virtio/virtio_user/vhost_kernel.c
@@ -70,6 +70,32 @@ static uint64_t vhost_req_user_to_kernel[] = {
        [VHOST_USER_SET_MEM_TABLE] = VHOST_SET_MEM_TABLE,
 };
 
+struct walk_arg {
+       struct vhost_memory_kernel *vm;
+       uint32_t region_nr;
+};
+static int
+add_memory_region(const struct rte_memseg *ms, size_t len, void *arg)
+{
+       struct walk_arg *wa = arg;
+       struct vhost_memory_region *mr;
+       void *start_addr;
+
+       if (wa->region_nr >= max_regions)
+               return -1;
+
+       mr = &wa->vm->regions[wa->region_nr++];
+       start_addr = ms->addr;
+
+       mr->guest_phys_addr = (uint64_t)(uintptr_t)start_addr;
+       mr->userspace_addr = (uint64_t)(uintptr_t)start_addr;
+       mr->memory_size = len;
+       mr->mmap_offset = 0;
+
+       return 0;
+}
+
+
 /* By default, vhost kernel module allows 64 regions, but DPDK allows
  * 256 segments. As a relief, below function merges those virtually
  * adjacent memsegs into one region.
@@ -77,63 +103,24 @@ static uint64_t vhost_req_user_to_kernel[] = {
 static struct vhost_memory_kernel *
 prepare_vhost_memory_kernel(void)
 {
-       uint32_t i, j, k = 0;
-       struct rte_memseg *seg;
-       struct vhost_memory_region *mr;
        struct vhost_memory_kernel *vm;
+       struct walk_arg wa;
 
        vm = malloc(sizeof(struct vhost_memory_kernel) +
-                   max_regions *
-                   sizeof(struct vhost_memory_region));
+                       max_regions *
+                       sizeof(struct vhost_memory_region));
        if (!vm)
                return NULL;
 
-       for (i = 0; i < RTE_MAX_MEMSEG; ++i) {
-               seg = &rte_eal_get_configuration()->mem_config->memseg[i];
-               if (!seg->addr)
-                       break;
-
-               int new_region = 1;
-
-               for (j = 0; j < k; ++j) {
-                       mr = &vm->regions[j];
+       wa.region_nr = 0;
+       wa.vm = vm;
 
-                       if (mr->userspace_addr + mr->memory_size ==
-                           (uint64_t)(uintptr_t)seg->addr) {
-                               mr->memory_size += seg->len;
-                               new_region = 0;
-                               break;
-                       }
-
-                       if ((uint64_t)(uintptr_t)seg->addr + seg->len ==
-                           mr->userspace_addr) {
-                               mr->guest_phys_addr =
-                                       (uint64_t)(uintptr_t)seg->addr;
-                               mr->userspace_addr =
-                                       (uint64_t)(uintptr_t)seg->addr;
-                               mr->memory_size += seg->len;
-                               new_region = 0;
-                               break;
-                       }
-               }
-
-               if (new_region == 0)
-                       continue;
-
-               mr = &vm->regions[k++];
-               /* use vaddr here! */
-               mr->guest_phys_addr = (uint64_t)(uintptr_t)seg->addr;
-               mr->userspace_addr = (uint64_t)(uintptr_t)seg->addr;
-               mr->memory_size = seg->len;
-               mr->mmap_offset = 0;
-
-               if (k >= max_regions) {
-                       free(vm);
-                       return NULL;
-               }
+       if (rte_memseg_contig_walk(add_memory_region, &wa) < 0) {
+               free(vm);
+               return NULL;
        }
 
-       vm->nregions = k;
+       vm->nregions = wa.region_nr;
        vm->padding = 0;
        return vm;
 }