nvme: move probe context as a internal data structure

Users should not access the internal probe context fields when
using the asynchronous probe API, so change spdk_nvme_probe_async()
to let it can only return the probe context pointer.

Change-Id: I0413c2d8db6cbe4539ad80919ed34dd621a9df70
Signed-off-by: Changpeng Liu <changpeng.liu@intel.com>
Reviewed-on: https://review.gerrithub.io/c/445870
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>

CHANGELOG.md

@@ -4,8 +4,8 @@
 
 ### nvme
 
-Added asynchronous probe support.  New APIs spdk_nvme_probe_ctx_init(), spdk_nvme_probe_async()
-and spdk_nvme_probe_poll_async() were added to enable this feature.
+Added asynchronous probe support.  New APIs spdk_nvme_probe_async() and
+spdk_nvme_probe_poll_async() were added to enable this feature.
 
 ### raid
 

include/spdk/nvme.h

@@ -566,19 +566,14 @@ struct spdk_nvme_ctrlr *spdk_nvme_connect(const struct spdk_nvme_transport_id *t
 		const struct spdk_nvme_ctrlr_opts *opts,
 		size_t opts_size);
 
-struct spdk_nvme_probe_ctx {
-	struct spdk_nvme_transport_id		trid;
-	void					*cb_ctx;
-	spdk_nvme_probe_cb			probe_cb;
-	spdk_nvme_attach_cb			attach_cb;
-	spdk_nvme_remove_cb			remove_cb;
-	TAILQ_HEAD(, spdk_nvme_ctrlr)		init_ctrlrs;
-};
+struct spdk_nvme_probe_ctx;
 
 /**
- * Initialize a context to track the probe result based on transport ID.
+ * Probe and add controllers to the probe context list.
+ *
+ * Users must call spdk_nvme_probe_poll_async() to initialize
+ * controllers in the probe context list to the READY state.
  *
- * \param probe_ctx Context used to track probe actions.
  * \param trid The transport ID indicating which bus to enumerate. If the trtype
  * is PCIe or trid is NULL, this will scan the local PCIe bus. If the trtype is
  * RDMA, the traddr and trsvcid must point at the location of an NVMe-oF discovery
@@ -592,25 +587,13 @@ struct spdk_nvme_probe_ctx {
  * spdk_nvme_probe() call but are no longer attached to the system. Optional;
  * specify NULL if removal notices are not desired.
  *
+ * \return probe context on success, NULL on failure.
  */
-void spdk_nvme_probe_ctx_init(struct spdk_nvme_probe_ctx *probe_ctx,
-			      const struct spdk_nvme_transport_id *trid,
-			      void *cb_ctx,
-			      spdk_nvme_probe_cb probe_cb,
-			      spdk_nvme_attach_cb attach_cb,
-			      spdk_nvme_remove_cb remove_cb);
-
-/**
- * Probe and add controllers to the probe context list.
- *
- * Users must call spdk_nvme_probe_poll_async() to initialize
- * controllers in the probe context list to the READY state.
- *
- * \param probe_ctx Context used to track probe actions.
- *
- * \return 0 on success, -1 on failure.
- */
-int spdk_nvme_probe_async(struct spdk_nvme_probe_ctx *probe_ctx);
+struct spdk_nvme_probe_ctx *spdk_nvme_probe_async(const struct spdk_nvme_transport_id *trid,
+		void *cb_ctx,
+		spdk_nvme_probe_cb probe_cb,
+		spdk_nvme_attach_cb attach_cb,
+		spdk_nvme_remove_cb remove_cb);
 
 /**
  * Start controllers in the context list.

lib/nvme/nvme.c

@@ -585,6 +585,22 @@ spdk_nvme_probe_internal(struct spdk_nvme_probe_ctx *probe_ctx,
 	return 0;
 }
 
+static void
+spdk_nvme_probe_ctx_init(struct spdk_nvme_probe_ctx *probe_ctx,
+			 const struct spdk_nvme_transport_id *trid,
+			 void *cb_ctx,
+			 spdk_nvme_probe_cb probe_cb,
+			 spdk_nvme_attach_cb attach_cb,
+			 spdk_nvme_remove_cb remove_cb)
+{
+	probe_ctx->trid = *trid;
+	probe_ctx->cb_ctx = cb_ctx;
+	probe_ctx->probe_cb = probe_cb;
+	probe_ctx->attach_cb = attach_cb;
+	probe_ctx->remove_cb = remove_cb;
+	TAILQ_INIT(&probe_ctx->init_ctrlrs);
+}
+
 int
 spdk_nvme_probe(const struct spdk_nvme_transport_id *trid, void *cb_ctx,
 		spdk_nvme_probe_cb probe_cb, spdk_nvme_attach_cb attach_cb,
@@ -1046,33 +1062,34 @@ spdk_nvme_prchk_flags_str(uint32_t prchk_flags)
 	}
 }
 
-void
-spdk_nvme_probe_ctx_init(struct spdk_nvme_probe_ctx *probe_ctx,
-			 const struct spdk_nvme_transport_id *trid,
-			 void *cb_ctx,
-			 spdk_nvme_probe_cb probe_cb,
-			 spdk_nvme_attach_cb attach_cb,
-			 spdk_nvme_remove_cb remove_cb)
-{
-	probe_ctx->trid = *trid;
-	probe_ctx->cb_ctx = cb_ctx;
-	probe_ctx->probe_cb = probe_cb;
-	probe_ctx->attach_cb = attach_cb;
-	probe_ctx->remove_cb = remove_cb;
-	TAILQ_INIT(&probe_ctx->init_ctrlrs);
-}
-
-int
-spdk_nvme_probe_async(struct spdk_nvme_probe_ctx *probe_ctx)
+struct spdk_nvme_probe_ctx *
+spdk_nvme_probe_async(const struct spdk_nvme_transport_id *trid,
+		      void *cb_ctx,
+		      spdk_nvme_probe_cb probe_cb,
+		      spdk_nvme_attach_cb attach_cb,
+		      spdk_nvme_remove_cb remove_cb)
 {
 	int rc;
+	struct spdk_nvme_probe_ctx *probe_ctx;
 
 	rc = nvme_driver_init();
 	if (rc != 0) {
-		return rc;
+		return NULL;
 	}
 
-	return spdk_nvme_probe_internal(probe_ctx, false);
+	probe_ctx = calloc(1, sizeof(*probe_ctx));
+	if (!probe_ctx) {
+		return NULL;
+	}
+
+	spdk_nvme_probe_ctx_init(probe_ctx, trid, cb_ctx, probe_cb, attach_cb, remove_cb);
+	rc = spdk_nvme_probe_internal(probe_ctx, false);
+	if (rc != 0) {
+		free(probe_ctx);
+		return NULL;
+	}
+
+	return probe_ctx;
 }
 
 bool

lib/nvme/nvme_internal.h

@@ -691,6 +691,15 @@ struct spdk_nvme_ctrlr {
 	uint32_t			outstanding_aborts;
 };
 
+struct spdk_nvme_probe_ctx {
+	struct spdk_nvme_transport_id		trid;
+	void					*cb_ctx;
+	spdk_nvme_probe_cb			probe_cb;
+	spdk_nvme_attach_cb			attach_cb;
+	spdk_nvme_remove_cb			remove_cb;
+	TAILQ_HEAD(, spdk_nvme_ctrlr)		init_ctrlrs;
+};
+
 struct nvme_driver {
 	pthread_mutex_t			lock;