nvme: add cuse support for RESCAN IOCTL

Nvme-cli submits a RESCAN IOCTL after a format command to
update any information that may have changed during the
format, such as LBA Format.  This patch adds support
for RESCAN by executing nvme_ctrlr_update_namespaces to
update the controller information.

Fixes: #1964

Change-Id: I9f03e00a7f39339947ff02390f69ce806e1cfa0e
Signed-off-by: Curt Bruns <curt.e.bruns@gmail.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/8146
Community-CI: Mellanox Build Bot
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Ziye Yang <ziye.yang@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>

lib/nvme/nvme_ctrlr.c

@@ -2533,7 +2533,7 @@ nvme_ctrlr_destruct_namespaces(struct spdk_nvme_ctrlr *ctrlr)
 	}
 }
 
-static void
+void
 nvme_ctrlr_update_namespaces(struct spdk_nvme_ctrlr *ctrlr)
 {
 	uint32_t i, nn = ctrlr->cdata.nn;

lib/nvme/nvme_cuse.c

@@ -313,6 +313,36 @@ cuse_nvme_reset(fuse_req_t req, int cmd, void *arg,
 	}
 }
 
+static void
+cuse_nvme_rescan_execute(struct spdk_nvme_ctrlr *ctrlr, uint32_t nsid, void *arg)
+{
+	fuse_req_t req = arg;
+
+	nvme_ctrlr_update_namespaces(ctrlr);
+	fuse_reply_ioctl_iov(req, 0, NULL, 0);
+}
+
+static void
+cuse_nvme_rescan(fuse_req_t req, int cmd, void *arg,
+		 struct fuse_file_info *fi, unsigned flags,
+		 const void *in_buf, size_t in_bufsz, size_t out_bufsz)
+{
+	int rv;
+	struct cuse_device *cuse_device = fuse_req_userdata(req);
+
+	if (cuse_device->nsid) {
+		SPDK_ERRLOG("Namespace rescan not supported\n");
+		fuse_reply_err(req, EINVAL);
+		return;
+	}
+
+	rv = nvme_io_msg_send(cuse_device->ctrlr, cuse_device->nsid, cuse_nvme_rescan_execute, (void *)req);
+	if (rv) {
+		SPDK_ERRLOG("Cannot send rescan\n");
+		fuse_reply_err(req, EINVAL);
+	}
+}
+
 /*****************************************************************************
  * Namespace IO requests
  */
@@ -615,6 +645,11 @@ cuse_ctrlr_ioctl(fuse_req_t req, int cmd, void *arg,
 		cuse_nvme_reset(req, cmd, arg, fi, flags, in_buf, in_bufsz, out_bufsz);
 		break;
 
+	case NVME_IOCTL_RESCAN:
+		SPDK_DEBUGLOG(nvme_cuse, "NVME_IOCTL_RESCAN\n");
+		cuse_nvme_rescan(req, cmd, arg, fi, flags, in_buf, in_bufsz, out_bufsz);
+		break;
+
 	default:
 		SPDK_ERRLOG("Unsupported IOCTL 0x%X.\n", cmd);
 		fuse_reply_err(req, EINVAL);

lib/nvme/nvme_internal.h

@@ -1318,6 +1318,7 @@ const struct spdk_nvme_transport *nvme_get_transport(const char *transport_name)
 const struct spdk_nvme_transport *nvme_get_first_transport(void);
 const struct spdk_nvme_transport *nvme_get_next_transport(const struct spdk_nvme_transport
 		*transport);
+void  nvme_ctrlr_update_namespaces(struct spdk_nvme_ctrlr *ctrlr);
 
 /* Transport specific functions */
 struct spdk_nvme_ctrlr *nvme_transport_ctrlr_construct(const struct spdk_nvme_transport_id *trid,

test/nvme/cuse/cuse.c

@@ -91,6 +91,8 @@ DEFINE_STUB(nvme_io_msg_ctrlr_register, int,
 DEFINE_STUB_V(nvme_io_msg_ctrlr_unregister,
 	      (struct spdk_nvme_ctrlr *ctrlr, struct nvme_io_msg_producer *io_msg_producer));
 
+DEFINE_STUB_V(nvme_ctrlr_update_namespaces, (struct spdk_nvme_ctrlr *ctrlr));
+
 static bool
 wait_for_file(char *filename, bool exists)
 {

test/unit/lib/nvme/nvme_cuse.c/nvme_cuse_ut.c

@@ -81,6 +81,8 @@ DEFINE_STUB(spdk_nvme_ctrlr_is_active_ns, bool,
 
 DEFINE_STUB(fuse_reply_err, int, (fuse_req_t req, int err), 0);
 
+DEFINE_STUB_V(nvme_ctrlr_update_namespaces, (struct spdk_nvme_ctrlr *ctrlr));
+
 struct cuse_io_ctx *g_ut_ctx;
 struct spdk_nvme_ctrlr *g_ut_ctrlr;
 uint32_t g_ut_nsid;