support VFIO_USER_REGION_WRITE_MULTI

FIXME: needs work Signed-off-by: John Levon <john.levon@nutanix.com>
nutanix · Aug 16, 2022 · aa183f9 · aa183f9
1 parent d307dbc
commit aa183f9
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Showing 3 changed files with 104 additions and 5 deletions.
diff --git a/include/vfio-user.h b/include/vfio-user.h
@@ -67,6 +67,7 @@ enum vfio_user_command {
  VFIO_USER_DMA_WRITE = 12,
  VFIO_USER_DEVICE_RESET = 13,
  VFIO_USER_DIRTY_PAGES = 14,
+ VFIO_USER_REGION_WRITE_MULTI = 15,
  VFIO_USER_MAX,
 };
 
@@ -226,6 +227,21 @@ struct vfio_user_bitmap_range {
 
 #endif /* VFIO_REGION_TYPE_MIGRATION */
 
+#define VFIO_USER_MULTI_DATA 8
+#define VFIO_USER_MULTI_MAX 200
+
+struct vfio_user_write_multi_data {
+ uint64_t offset;
+ uint32_t region;
+ uint32_t count;
+ char data[VFIO_USER_MULTI_DATA];
+} __attribute__((packed));
+
+struct vfio_user_write_multi {
+ uint64_t wr_cnt;
+ struct vfio_user_write_multi_data wrs[VFIO_USER_MULTI_MAX];
+} __attribute__((packed));
+
 #ifdef __cplusplus
 }
 #endif

diff --git a/lib/libvfio-user.c b/lib/libvfio-user.c
@@ -264,10 +264,27 @@ is_valid_region_access(vfu_ctx_t *vfu_ctx, size_t size, uint16_t cmd,
  return false;
  }
 
- if (cmd == VFIO_USER_REGION_WRITE && size - sizeof(*ra) != ra->count) {
- vfu_log(vfu_ctx, LOG_ERR, "region write count too small: "
- "expected %lu, got %u", size - sizeof(*ra), ra->count);
- return false;
+ switch (cmd) {
+ case VFIO_USER_REGION_WRITE:
+ if (size - sizeof(*ra) != ra->count) {
+ vfu_log(vfu_ctx, LOG_ERR, "region write count too small: "
+ "expected %lu, got %u", size - sizeof(*ra), ra->count);
+ return false;
+ }
+
+ break;
+
+ case VFIO_USER_REGION_WRITE_MULTI:
+ if (ra->count > VFIO_USER_MULTI_DATA) {
+ vfu_log(vfu_ctx, LOG_ERR, "region write count too large: "
+ "expected %lu, got %u", size - sizeof(*ra), ra->count);
+ return false;
+ }
+
+ break;
+
+ default:
+ break;
  }
 
  index = ra->region;
@@ -350,6 +367,61 @@ handle_region_access(vfu_ctx_t *vfu_ctx, vfu_msg_t *msg)
  return 0;
 }
 
+static int
+handle_region_write_multi(vfu_ctx_t *vfu_ctx, vfu_msg_t *msg)
+{
+ struct vfio_user_write_multi *wm = msg->in.iov.iov_base;
+ ssize_t ret;
+ char *buf;
+
+ assert(vfu_ctx != NULL);
+ assert(msg != NULL);
+
+ // FIXME: validate properly (?)
+
+ if (msg->in.iov.iov_len < sizeof(*wm)) {
+ return ERROR_INT(EINVAL);
+ }
+
+ if (wm->wr_cnt > VFIO_USER_MULTI_MAX) {
+ return ERROR_INT(EINVAL);
+ }
+
+ for (size_t i = 0; i < wm->wr_cnt; i++) {
+ struct vfio_user_region_access *in_ra;
+
+ /* Re-use the very similar type. */
+ in_ra = (struct vfio_user_region_access *)&wm->wrs[i];
+
+ /*
+ * We already checked total length so can be sure each entry is at least
+ * big enough.
+ */
+ if (!is_valid_region_access(vfu_ctx, sizeof(wm->wrs[i]),
+ msg->hdr.cmd, in_ra)) {
+ return ERROR_INT(EINVAL);
+ }
+
+ if (in_ra->count == 0) {
+ continue;
+ }
+
+ buf = (char *)(&in_ra->data);
+
+ ret = region_access(vfu_ctx, in_ra->region, buf, in_ra->count,
+ in_ra->offset, true);
+ if (ret != in_ra->count) {
+ /* FIXME we should return whatever has been accessed, not an error */
+ if (ret >= 0) {
+ ret = ERROR_INT(EINVAL);
+ }
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
 static int
 handle_device_get_info(vfu_ctx_t *vfu_ctx, vfu_msg_t *msg)
 {
@@ -1146,6 +1218,11 @@ handle_request(vfu_ctx_t *vfu_ctx, vfu_msg_t *msg)
  ret = handle_region_access(vfu_ctx, msg);
  break;
 
+ case VFIO_USER_REGION_WRITE_MULTI:
+ ret = handle_region_write_multi(vfu_ctx, msg);
+ break;
+
+
  case VFIO_USER_DEVICE_RESET:
  vfu_log(vfu_ctx, LOG_INFO, "device reset by client");
  ret = handle_device_reset(vfu_ctx, VFU_RESET_DEVICE);
@@ -1334,6 +1411,10 @@ command_needs_quiesce(vfu_ctx_t *vfu_ctx, const vfu_msg_t *msg)
  return true;
  }
  break;
+
+ case VFIO_USER_REGION_WRITE_MULTI:
+ /* FIXME */
+ return false;
  }
 
  return false;

diff --git a/test/py/libvfio_user.py b/test/py/libvfio_user.py
@@ -158,7 +158,9 @@
 VFIO_USER_DMA_WRITE = 12
 VFIO_USER_DEVICE_RESET = 13
 VFIO_USER_DIRTY_PAGES = 14
-VFIO_USER_MAX = 15
+# FIXME: need tests
+VFIO_USER_REGION_WRITE_MULTI = 15
+VFIO_USER_MAX = 16
 
 VFIO_USER_F_TYPE_COMMAND = 0
 VFIO_USER_F_TYPE_REPLY = 1