bdev/rpc: Add descriptive error messages for malloc bdevs

Provide more error codes and/or messages then just a
generic "32602 invalid parameters" error.

Change-Id: I1777f454faef336b10af24dda50a2d5b5e73727f
Signed-off-by: Karol Latecki <karol.latecki@intel.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/459948
Reviewed-by: Vitaliy Mysak <vitaliy.mysak@intel.com>
Reviewed-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>

lib/bdev/malloc/bdev_malloc.c

@@ -390,21 +390,22 @@ static const struct spdk_bdev_fn_table malloc_fn_table = {
 	.write_config_json	= bdev_malloc_write_json_config,
 };
 
-struct spdk_bdev *create_malloc_disk(const char *name, const struct spdk_uuid *uuid,
+int
-				     uint64_t num_blocks, uint32_t block_size)
+create_malloc_disk(struct spdk_bdev **bdev, const char *name, const struct spdk_uuid *uuid,
+		   uint64_t num_blocks, uint32_t block_size)
 {
 	struct malloc_disk	*mdisk;
-	int			rc;
+	int rc;
 
 	if (num_blocks == 0) {
-		SPDK_ERRLOG("Disk must be more than 0 blocks\n");
+		SPDK_ERRLOG("Disk num_blocks must be greater than 0");
-		return NULL;
+		return -EINVAL;
 	}
 
 	mdisk = calloc(1, sizeof(*mdisk));
 	if (!mdisk) {
 		SPDK_ERRLOG("mdisk calloc() failed\n");
-		return NULL;
+		return -ENOMEM;
 	}
 
 	/*
@@ -418,7 +419,7 @@ struct spdk_bdev *create_malloc_disk(const char *name, const struct spdk_uuid *u
 	if (!mdisk->malloc_buf) {
 		SPDK_ERRLOG("malloc_buf spdk_zmalloc() failed\n");
 		malloc_disk_free(mdisk);
-		return NULL;
+		return -ENOMEM;
 	}
 
 	if (name) {
@@ -430,7 +431,7 @@ struct spdk_bdev *create_malloc_disk(const char *name, const struct spdk_uuid *u
 	}
 	if (!mdisk->disk.name) {
 		malloc_disk_free(mdisk);
-		return NULL;
+		return -ENOMEM;
 	}
 	mdisk->disk.product_name = "Malloc disk";
 
@@ -450,12 +451,14 @@ struct spdk_bdev *create_malloc_disk(const char *name, const struct spdk_uuid *u
 	rc = spdk_bdev_register(&mdisk->disk);
 	if (rc) {
 		malloc_disk_free(mdisk);
-		return NULL;
+		return rc;
 	}
 
+	*bdev = &(mdisk->disk);
+
 	TAILQ_INSERT_TAIL(&g_malloc_disks, mdisk, link);
 
-	return &mdisk->disk;
+	return rc;
 }
 
 void
@@ -490,10 +493,9 @@ static int bdev_malloc_initialize(void)
 		}
 		size = (uint64_t)LunSizeInMB * 1024 * 1024;
 		for (i = 0; i < NumberOfLuns; i++) {
-			bdev = create_malloc_disk(NULL, NULL, size / BlockSize, BlockSize);
+			rc = create_malloc_disk(&bdev, NULL, NULL, size / BlockSize, BlockSize);
-			if (bdev == NULL) {
+			if (rc) {
 				SPDK_ERRLOG("Could not create malloc disk\n");
-				rc = EINVAL;
 				goto end;
 			}
 		}

lib/bdev/malloc/bdev_malloc.h

@@ -40,8 +40,8 @@
 
 typedef void (*spdk_delete_malloc_complete)(void *cb_arg, int bdeverrno);
 
-struct spdk_bdev *create_malloc_disk(const char *name, const struct spdk_uuid *uuid,
+int create_malloc_disk(struct spdk_bdev **bdev, const char *name, const struct spdk_uuid *uuid,
-				     uint64_t num_blocks, uint32_t block_size);
+		       uint64_t num_blocks, uint32_t block_size);
 
 void delete_malloc_disk(struct spdk_bdev *bdev, spdk_delete_malloc_complete cb_fn, void *cb_arg);
 

lib/bdev/malloc/bdev_malloc_rpc.c

@@ -68,24 +68,36 @@ spdk_rpc_construct_malloc_bdev(struct spdk_jsonrpc_request *request,
 	struct spdk_uuid *uuid = NULL;
 	struct spdk_uuid decoded_uuid;
 	struct spdk_bdev *bdev;
+	int rc = 0;
 
 	if (spdk_json_decode_object(params, rpc_construct_malloc_decoders,
 				    SPDK_COUNTOF(rpc_construct_malloc_decoders),
 				    &req)) {
 		SPDK_DEBUGLOG(SPDK_LOG_BDEV_MALLOC, "spdk_json_decode_object failed\n");
-		goto invalid;
+		spdk_jsonrpc_send_error_response(request, SPDK_JSONRPC_ERROR_INTERNAL_ERROR,
+						 "spdk_json_decode_object failed");
+		goto cleanup;
+	}
+
+	if (req.num_blocks == 0) {
+		spdk_jsonrpc_send_error_response(request, -EINVAL,
+						 "Disk num_blocks must be greater than 0");
+		goto cleanup;
 	}
 
 	if (req.uuid) {
 		if (spdk_uuid_parse(&decoded_uuid, req.uuid)) {
-			goto invalid;
+			spdk_jsonrpc_send_error_response(request, -EINVAL,
+							 "Failed to parse bdev UUID");
+			goto cleanup;
 		}
 		uuid = &decoded_uuid;
 	}
 
-	bdev = create_malloc_disk(req.name, uuid, req.num_blocks, req.block_size);
+	rc = create_malloc_disk(&bdev, req.name, uuid, req.num_blocks, req.block_size);
-	if (bdev == NULL) {
+	if (rc) {
-		goto invalid;
+		spdk_jsonrpc_send_error_response(request, rc, spdk_strerror(-rc));
+		goto cleanup;
 	}
 
 	free_rpc_construct_malloc(&req);
@@ -99,9 +111,8 @@ spdk_rpc_construct_malloc_bdev(struct spdk_jsonrpc_request *request,
 	spdk_jsonrpc_end_result(request, w);
 	return;
 
-invalid:
+cleanup:
 	free_rpc_construct_malloc(&req);
-	spdk_jsonrpc_send_error_response(request, SPDK_JSONRPC_ERROR_INVALID_PARAMS, "Invalid parameters");
 }
 SPDK_RPC_REGISTER("construct_malloc_bdev", spdk_rpc_construct_malloc_bdev, SPDK_RPC_RUNTIME)
 
@@ -140,21 +151,21 @@ spdk_rpc_delete_malloc_bdev(struct spdk_jsonrpc_request *request,
 {
 	struct rpc_delete_malloc req = {NULL};
 	struct spdk_bdev *bdev;
-	int rc;
 
 	if (spdk_json_decode_object(params, rpc_delete_malloc_decoders,
 				    SPDK_COUNTOF(rpc_delete_malloc_decoders),
 				    &req)) {
 		SPDK_DEBUGLOG(SPDK_LOG_BDEV_MALLOC, "spdk_json_decode_object failed\n");
-		rc = -EINVAL;
+		spdk_jsonrpc_send_error_response(request, SPDK_JSONRPC_ERROR_INTERNAL_ERROR,
-		goto invalid;
+						 "spdk_json_decode_object failed");
+		goto cleanup;
 	}
 
 	bdev = spdk_bdev_get_by_name(req.name);
 	if (bdev == NULL) {
 		SPDK_INFOLOG(SPDK_LOG_BDEV_MALLOC, "bdev '%s' does not exist\n", req.name);
-		rc = -ENODEV;
+		spdk_jsonrpc_send_error_response(request, -ENODEV, spdk_strerror(ENODEV));
-		goto invalid;
+		goto cleanup;
 	}
 
 	delete_malloc_disk(bdev, _spdk_rpc_delete_malloc_bdev_cb, request);
@@ -163,8 +174,7 @@ spdk_rpc_delete_malloc_bdev(struct spdk_jsonrpc_request *request,
 
 	return;
 
-invalid:
+cleanup:
 	free_rpc_delete_malloc(&req);
-	spdk_jsonrpc_send_error_response(request, SPDK_JSONRPC_ERROR_INVALID_PARAMS, spdk_strerror(-rc));
 }
 SPDK_RPC_REGISTER("delete_malloc_bdev", spdk_rpc_delete_malloc_bdev, SPDK_RPC_RUNTIME)