vhost: replace SMP with thread fence for control path

[dpdk.git] / lib / librte_vhost / vhost_user.c

diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
index 8a8726f..6e94a9b 100644 (file)
--- a/lib/librte_vhost/vhost_user.c
+++ b/lib/librte_vhost/vhost_user.c
@@ -99,8 +99,15 @@ close_msg_fds(struct VhostUserMsg *msg)
 {
        int i;
 
-       for (i = 0; i < msg->fd_num; i++)
-               close(msg->fds[i]);
+       for (i = 0; i < msg->fd_num; i++) {
+               int fd = msg->fds[i];
+
+               if (fd == -1)
+                       continue;
+
+               msg->fds[i] = -1;
+               close(fd);
+       }
 }
 
 /*
@@ -1004,7 +1011,6 @@ vhost_user_set_mem_table(struct virtio_net **pdev, struct VhostUserMsg *msg,
        uint64_t alignment;
        uint32_t i;
        int populate;
-       int fd;
 
        if (validate_msg_fds(msg, memory->nregions) != 0)
                return RTE_VHOST_MSG_RESULT_ERR;
@@ -1012,7 +1018,7 @@ vhost_user_set_mem_table(struct virtio_net **pdev, struct VhostUserMsg *msg,
        if (memory->nregions > VHOST_MEMORY_MAX_NREGIONS) {
                VHOST_LOG_CONFIG(ERR,
                        "too many memory regions (%u)\n", memory->nregions);
-               return RTE_VHOST_MSG_RESULT_ERR;
+               goto close_msg_fds;
        }
 
        if (dev->mem && !vhost_memory_changed(memory, dev->mem)) {
@@ -1054,7 +1060,7 @@ vhost_user_set_mem_table(struct virtio_net **pdev, struct VhostUserMsg *msg,
                                "(%d) failed to allocate memory "
                                "for dev->guest_pages\n",
                                dev->vid);
-                       return RTE_VHOST_MSG_RESULT_ERR;
+                       goto close_msg_fds;
                }
        }
 
@@ -1064,18 +1070,23 @@ vhost_user_set_mem_table(struct virtio_net **pdev, struct VhostUserMsg *msg,
                VHOST_LOG_CONFIG(ERR,
                        "(%d) failed to allocate memory for dev->mem\n",
                        dev->vid);
-               return RTE_VHOST_MSG_RESULT_ERR;
+               goto free_guest_pages;
        }
        dev->mem->nregions = memory->nregions;
 
        for (i = 0; i < memory->nregions; i++) {
-               fd  = msg->fds[i];
                reg = &dev->mem->regions[i];
 
                reg->guest_phys_addr = memory->regions[i].guest_phys_addr;
                reg->guest_user_addr = memory->regions[i].userspace_addr;
                reg->size            = memory->regions[i].memory_size;
-               reg->fd              = fd;
+               reg->fd              = msg->fds[i];
+
+               /*
+                * Assign invalid file descriptor value to avoid double
+                * closing on error path.
+                */
+               msg->fds[i] = -1;
 
                mmap_offset = memory->regions[i].mmap_offset;
 
@@ -1085,7 +1096,7 @@ vhost_user_set_mem_table(struct virtio_net **pdev, struct VhostUserMsg *msg,
                                "mmap_offset (%#"PRIx64") and memory_size "
                                "(%#"PRIx64") overflow\n",
                                mmap_offset, reg->size);
-                       goto err_mmap;
+                       goto free_mem_table;
                }
 
                mmap_size = reg->size + mmap_offset;
@@ -1098,11 +1109,11 @@ vhost_user_set_mem_table(struct virtio_net **pdev, struct VhostUserMsg *msg,
                 * to avoid failure, make sure in caller to keep length
                 * aligned.
                 */
-               alignment = get_blk_size(fd);
+               alignment = get_blk_size(reg->fd);
                if (alignment == (uint64_t)-1) {
                        VHOST_LOG_CONFIG(ERR,
                                "couldn't get hugepage size through fstat\n");
-                       goto err_mmap;
+                       goto free_mem_table;
                }
                mmap_size = RTE_ALIGN_CEIL(mmap_size, alignment);
                if (mmap_size == 0) {
@@ -1118,17 +1129,17 @@ vhost_user_set_mem_table(struct virtio_net **pdev, struct VhostUserMsg *msg,
                        VHOST_LOG_CONFIG(ERR, "mmap size (0x%" PRIx64 ") "
                                        "or alignment (0x%" PRIx64 ") is invalid\n",
                                        reg->size + mmap_offset, alignment);
-                       goto err_mmap;
+                       goto free_mem_table;
                }
 
                populate = dev->async_copy ? MAP_POPULATE : 0;
                mmap_addr = mmap(NULL, mmap_size, PROT_READ | PROT_WRITE,
-                                MAP_SHARED | populate, fd, 0);
+                                MAP_SHARED | populate, reg->fd, 0);
 
                if (mmap_addr == MAP_FAILED) {
                        VHOST_LOG_CONFIG(ERR,
                                "mmap region %u failed.\n", i);
-                       goto err_mmap;
+                       goto free_mem_table;
                }
 
                reg->mmap_addr = mmap_addr;
@@ -1141,7 +1152,7 @@ vhost_user_set_mem_table(struct virtio_net **pdev, struct VhostUserMsg *msg,
                                VHOST_LOG_CONFIG(ERR,
                                        "adding guest pages to region %u failed.\n",
                                        i);
-                               goto err_mmap;
+                               goto free_mem_table;
                        }
 
                VHOST_LOG_CONFIG(INFO,
@@ -1184,17 +1195,17 @@ vhost_user_set_mem_table(struct virtio_net **pdev, struct VhostUserMsg *msg,
                if (read_vhost_message(main_fd, &ack_msg) <= 0) {
                        VHOST_LOG_CONFIG(ERR,
                                "Failed to read qemu ack on postcopy set-mem-table\n");
-                       goto err_mmap;
+                       goto free_mem_table;
                }
 
                if (validate_msg_fds(&ack_msg, 0) != 0)
-                       goto err_mmap;
+                       goto free_mem_table;
 
                if (ack_msg.request.master != VHOST_USER_SET_MEM_TABLE) {
                        VHOST_LOG_CONFIG(ERR,
                                "Bad qemu ack on postcopy set-mem-table (%d)\n",
                                ack_msg.request.master);
-                       goto err_mmap;
+                       goto free_mem_table;
                }
 
                /* Now userfault register and we can use the memory */
@@ -1218,7 +1229,7 @@ vhost_user_set_mem_table(struct virtio_net **pdev, struct VhostUserMsg *msg,
                                        "Failed to register ufd for region %d: (ufd = %d) %s\n",
                                        i, dev->postcopy_ufd,
                                        strerror(errno));
-                               goto err_mmap;
+                               goto free_mem_table;
                        }
                        VHOST_LOG_CONFIG(INFO,
                                "\t userfaultfd registered for range : "
@@ -1227,7 +1238,7 @@ vhost_user_set_mem_table(struct virtio_net **pdev, struct VhostUserMsg *msg,
                                (uint64_t)reg_struct.range.start +
                                (uint64_t)reg_struct.range.len - 1);
 #else
-                       goto err_mmap;
+                       goto free_mem_table;
 #endif
                }
        }
@@ -1249,7 +1260,7 @@ vhost_user_set_mem_table(struct virtio_net **pdev, struct VhostUserMsg *msg,
                        dev = translate_ring_addresses(dev, i);
                        if (!dev) {
                                dev = *pdev;
-                               goto err_mmap;
+                               goto free_mem_table;
                        }
 
                        *pdev = dev;
@@ -1260,10 +1271,15 @@ vhost_user_set_mem_table(struct virtio_net **pdev, struct VhostUserMsg *msg,
 
        return RTE_VHOST_MSG_RESULT_OK;
 
-err_mmap:
+free_mem_table:
        free_mem_region(dev);
        rte_free(dev->mem);
        dev->mem = NULL;
+free_guest_pages:
+       rte_free(dev->guest_pages);
+       dev->guest_pages = NULL;
+close_msg_fds:
+       close_msg_fds(msg);
        return RTE_VHOST_MSG_RESULT_ERR;
 }
 
@@ -1674,7 +1690,7 @@ vhost_check_queue_inflights_split(struct virtio_net *dev,
 
        if (inflight_split->used_idx != used->idx) {
                inflight_split->desc[last_io].inflight = 0;
-               rte_smp_mb();
+               rte_atomic_thread_fence(__ATOMIC_SEQ_CST);
                inflight_split->used_idx = used->idx;
        }
 
@@ -1842,8 +1858,12 @@ vhost_user_set_vring_kick(struct virtio_net **pdev, struct VhostUserMsg *msg,
 
        /* Interpret ring addresses only when ring is started. */
        dev = translate_ring_addresses(dev, file.index);
-       if (!dev)
+       if (!dev) {
+               if (file.fd != VIRTIO_INVALID_EVENTFD)
+                       close(file.fd);
+
                return RTE_VHOST_MSG_RESULT_ERR;
+       }
 
        *pdev = dev;
 
@@ -2070,7 +2090,7 @@ vhost_user_set_log_base(struct virtio_net **pdev, struct VhostUserMsg *msg,
                VHOST_LOG_CONFIG(ERR,
                        "invalid log base msg size: %"PRId32" != %d\n",
                        msg->size, (int)sizeof(VhostUserLog));
-               return RTE_VHOST_MSG_RESULT_ERR;
+               goto close_msg_fds;
        }
 
        size = msg->payload.log.mmap_size;
@@ -2081,7 +2101,7 @@ vhost_user_set_log_base(struct virtio_net **pdev, struct VhostUserMsg *msg,
                VHOST_LOG_CONFIG(ERR,
                        "log offset %#"PRIx64" and log size %#"PRIx64" overflow\n",
                        off, size);
-               return RTE_VHOST_MSG_RESULT_ERR;
+               goto close_msg_fds;
        }
 
        VHOST_LOG_CONFIG(INFO,
@@ -2118,6 +2138,10 @@ vhost_user_set_log_base(struct virtio_net **pdev, struct VhostUserMsg *msg,
        msg->fd_num = 0;
 
        return RTE_VHOST_MSG_RESULT_REPLY;
+
+close_msg_fds:
+       close_msg_fds(msg);
+       return RTE_VHOST_MSG_RESULT_ERR;
 }
 
 static int vhost_user_set_log_fd(struct virtio_net **pdev __rte_unused,