vhost: refactor postcopy region registration

This patch moves the registration of memory regions to
userfaultfd to a dedicated function, with the goal of
simplifying VHOST_USER_SET_MEM_TABLE request handling
function.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Chenbo Xia <chenbo.xia@intel.com>

diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
index 6e94a9b..5b61eef 100644 (file)
--- a/lib/librte_vhost/vhost_user.c
+++ b/lib/librte_vhost/vhost_user.c
@@ -998,6 +998,49 @@ vhost_memory_changed(struct VhostUserMemory *new,
        return false;
 }
 
+#ifdef RTE_LIBRTE_VHOST_POSTCOPY
+static int
+vhost_user_postcopy_region_register(struct virtio_net *dev,
+               struct rte_vhost_mem_region *reg)
+{
+       struct uffdio_register reg_struct;
+
+       /*
+        * Let's register all the mmap'ed area to ensure
+        * alignment on page boundary.
+        */
+       reg_struct.range.start = (uint64_t)(uintptr_t)reg->mmap_addr;
+       reg_struct.range.len = reg->mmap_size;
+       reg_struct.mode = UFFDIO_REGISTER_MODE_MISSING;
+
+       if (ioctl(dev->postcopy_ufd, UFFDIO_REGISTER,
+                               &reg_struct)) {
+               VHOST_LOG_CONFIG(ERR, "Failed to register ufd for region "
+                               "%" PRIx64 " - %" PRIx64 " (ufd = %d) %s\n",
+                               (uint64_t)reg_struct.range.start,
+                               (uint64_t)reg_struct.range.start +
+                               (uint64_t)reg_struct.range.len - 1,
+                               dev->postcopy_ufd,
+                               strerror(errno));
+               return -1;
+       }
+
+       VHOST_LOG_CONFIG(INFO, "\t userfaultfd registered for range : %" PRIx64 " - %" PRIx64 "\n",
+                       (uint64_t)reg_struct.range.start,
+                       (uint64_t)reg_struct.range.start +
+                       (uint64_t)reg_struct.range.len - 1);
+
+       return 0;
+}
+#else
+static int
+vhost_user_postcopy_region_register(struct virtio_net *dev __rte_unused,
+               struct rte_vhost_mem_region *reg __rte_unused)
+{
+       return -1;
+}
+#endif
+
 static int
 vhost_user_set_mem_table(struct virtio_net **pdev, struct VhostUserMsg *msg,
                        int main_fd)
@@ -1209,38 +1252,10 @@ vhost_user_set_mem_table(struct virtio_net **pdev, struct VhostUserMsg *msg,
                }
 
                /* Now userfault register and we can use the memory */
-               for (i = 0; i < memory->nregions; i++) {
-#ifdef RTE_LIBRTE_VHOST_POSTCOPY
-                       reg = &dev->mem->regions[i];
-                       struct uffdio_register reg_struct;
-
-                       /*
-                        * Let's register all the mmap'ed area to ensure
-                        * alignment on page boundary.
-                        */
-                       reg_struct.range.start =
-                               (uint64_t)(uintptr_t)reg->mmap_addr;
-                       reg_struct.range.len = reg->mmap_size;
-                       reg_struct.mode = UFFDIO_REGISTER_MODE_MISSING;
-
-                       if (ioctl(dev->postcopy_ufd, UFFDIO_REGISTER,
-                                               &reg_struct)) {
-                               VHOST_LOG_CONFIG(ERR,
-                                       "Failed to register ufd for region %d: (ufd = %d) %s\n",
-                                       i, dev->postcopy_ufd,
-                                       strerror(errno));
+               for (i = 0; i < memory->nregions; i++)
+                       if (vhost_user_postcopy_region_register(dev,
+                                               &dev->mem->regions[i]) < 0)
                                goto free_mem_table;
-                       }
-                       VHOST_LOG_CONFIG(INFO,
-                               "\t userfaultfd registered for range : "
-                               "%" PRIx64 " - %" PRIx64 "\n",
-                               (uint64_t)reg_struct.range.start,
-                               (uint64_t)reg_struct.range.start +
-                               (uint64_t)reg_struct.range.len - 1);
-#else
-                       goto free_mem_table;
-#endif
-               }
        }
 
        for (i = 0; i < dev->nr_vring; i++) {