bdev: Separate the module header from the public header

Bdev modules need a separate interface than public
consumers of the blockdevs.

Change-Id: I581ee493570c114f7e96b31a425bc077a791c71e
Signed-off-by: Ben Walker <benjamin.walker@intel.com>

include/spdk/bdev.h

@@ -56,40 +56,6 @@
 
 struct spdk_bdev_io;
 
-/** \page block_backend_modules Block Device Backend Modules
-
-To implement a backend block device driver, a number of functions
-dictated by struct spdk_bdev_fn_table must be provided.
-
-The module should register itself using SPDK_BDEV_MODULE_REGISTER or
-SPDK_VBDEV_MODULE_REGISTER to define the parameters for the module.
-
-Use SPDK_BDEV_MODULE_REGISTER for all block backends that are real disks.
-Any virtual backends such as RAID, partitioning, etc. should use
-SPDK_VBDEV_MODULE_REGISTER.
-
-<hr>
-
-In the module initialization code, the config file sections can be parsed to
-acquire custom configuration parameters. For example, if the config file has
-a section such as below:
-<blockquote><pre>
-[MyBE]
-  MyParam 1234
-</pre></blockquote>
-
-The value can be extracted as the example below:
-<blockquote><pre>
-struct spdk_conf_section *sp = spdk_conf_find_section(NULL, "MyBe");
-int my_param = spdk_conf_section_get_intval(sp, "MyParam");
-</pre></blockquote>
-
-The backend initialization routine also need to create "disks". A virtual
-representation of each LUN must be constructed. Mainly a struct spdk_bdev
-must be passed to the bdev database via spdk_bdev_register().
-
-*/
-
 /**
  * \brief SPDK block device.
  *
@@ -320,53 +286,8 @@ struct spdk_bdev_io {
 	/* No members may be added after driver_ctx! */
 };
 
-/** Block device module */
-struct spdk_bdev_module_if {
-	/**
-	 * Initialization function for the module.  Called by the spdk
-	 * application during startup.
-	 *
-	 * Modules are required to define this function.
-	 */
-	int (*module_init)(void);
-
-	/**
-	 * Finish function for the module.  Called by the spdk application
-	 * before the spdk application exits to perform any necessary cleanup.
-	 *
-	 * Modules are not required to define this function.
-	 */
-	void (*module_fini)(void);
-
-	/**
-	 * Function called to return a text string representing the
-	 * module's configuration options for inclusion in a configuration file.
-	 */
-	void (*config_text)(FILE *fp);
-
-	/** Name for the modules being defined. */
-	const char *module_name;
-
-	/**
-	 * Returns the allocation size required for the backend for uses such as local
-	 * command structs, local SGL, iovecs, or other user context.
-	 */
-	int (*get_ctx_size)(void);
-
-	TAILQ_ENTRY(spdk_bdev_module_if) tailq;
-};
-
-/* The blockdev API has two distinct parts. The first portion of the API
- * is to be used by the layer above the blockdev in order to communicate
- * with it. The second portion of the API is to be used by the blockdev
- * modules themselves to perform operations like completing I/O.
- */
-
-/* The following functions are intended to be called from the upper layer
- * that is using the blockdev layer.
- */
-
 struct spdk_bdev *spdk_bdev_get_by_name(const char *bdev_name);
+void spdk_bdev_unregister(struct spdk_bdev *bdev);
 
 struct spdk_bdev *spdk_bdev_first(void);
 struct spdk_bdev *spdk_bdev_next(struct spdk_bdev *prev);
@@ -392,55 +313,8 @@ struct spdk_bdev_io *spdk_bdev_flush(struct spdk_bdev *bdev,
 				     spdk_bdev_io_completion_cb cb, void *cb_arg);
 int spdk_bdev_io_submit(struct spdk_bdev_io *bdev_io);
 void spdk_bdev_do_work(void *ctx);
-int spdk_bdev_reset(struct spdk_bdev *bdev, enum spdk_bdev_reset_type reset_type,
+int spdk_bdev_free_io(struct spdk_bdev_io *bdev_io);
+int spdk_bdev_reset(struct spdk_bdev *bdev, enum spdk_bdev_reset_type,
 		    spdk_bdev_io_completion_cb cb, void *cb_arg);
 
-/* The remaining functions are intended to be called from within
- * blockdev modules.
- */
-void spdk_bdev_register(struct spdk_bdev *bdev);
-void spdk_bdev_unregister(struct spdk_bdev *bdev);
-int spdk_bdev_free_io(struct spdk_bdev_io *bdev_io);
-void spdk_bdev_io_get_rbuf(struct spdk_bdev_io *bdev_io, spdk_bdev_io_get_rbuf_cb cb);
-struct spdk_bdev_io *spdk_bdev_get_io(void);
-struct spdk_bdev_io *spdk_bdev_get_child_io(struct spdk_bdev_io *parent,
-		struct spdk_bdev *bdev,
-		spdk_bdev_io_completion_cb cb,
-		void *cb_arg);
-void spdk_bdev_io_complete(struct spdk_bdev_io *bdev_io,
-			   enum spdk_bdev_io_status status);
-void spdk_bdev_module_list_add(struct spdk_bdev_module_if *bdev_module);
-void spdk_vbdev_module_list_add(struct spdk_bdev_module_if *vbdev_module);
-
-static inline struct spdk_bdev_io *
-spdk_bdev_io_from_ctx(void *ctx)
-{
-	return (struct spdk_bdev_io *)
-	       ((uintptr_t)ctx - offsetof(struct spdk_bdev_io, driver_ctx));
-}
-
-#define SPDK_BDEV_MODULE_REGISTER(init_fn, fini_fn, config_fn, ctx_size_fn)			\
-	static struct spdk_bdev_module_if init_fn ## _if = {					\
-	.module_init 	= init_fn,								\
-	.module_fini	= fini_fn,								\
-	.config_text	= config_fn,								\
-	.get_ctx_size	= ctx_size_fn,                                				\
-	};  											\
-	__attribute__((constructor)) static void init_fn ## _init(void)  			\
-	{                                                           				\
-	    spdk_bdev_module_list_add(&init_fn ## _if);                  			\
-	}
-
-#define SPDK_VBDEV_MODULE_REGISTER(init_fn, fini_fn, config_fn, ctx_size_fn)			\
-	static struct spdk_bdev_module_if init_fn ## _if = {					\
-	.module_init 	= init_fn,								\
-	.module_fini	= fini_fn,								\
-	.config_text	= config_fn,								\
-	.get_ctx_size	= ctx_size_fn,                                				\
-	};  											\
-	__attribute__((constructor)) static void init_fn ## _init(void)  			\
-	{                                                           				\
-	    spdk_vbdev_module_list_add(&init_fn ## _if);                  			\
-	}
-
 #endif /* SPDK_BDEV_H_ */

lib/bdev/Makefile

@@ -34,7 +34,7 @@
 SPDK_ROOT_DIR := $(abspath $(CURDIR)/../..)
 include $(SPDK_ROOT_DIR)/mk/spdk.common.mk
 
-CFLAGS += $(DPDK_INC)
+CFLAGS += $(DPDK_INC) -I.
 C_SRCS = bdev.c
 LIBNAME = bdev
 

lib/bdev/aio/Makefile

@@ -34,6 +34,7 @@
 SPDK_ROOT_DIR := $(abspath $(CURDIR)/../../..)
 include $(SPDK_ROOT_DIR)/mk/spdk.common.mk
 
+CFLAGS += -I$(SPDK_ROOT_DIR)/lib/bdev/
 C_SRCS = blockdev_aio.c blockdev_aio_rpc.c
 LIBNAME = bdev_aio
 

lib/bdev/aio/blockdev_aio.h

@@ -40,6 +40,8 @@
 #include "spdk/queue.h"
 #include "spdk/bdev.h"
 
+#include "bdev_module.h"
+
 struct blockdev_aio_task {
 	struct iocb			iocb;
 	uint64_t			len;

lib/bdev/bdev.c

@@ -49,6 +49,8 @@
 #include "spdk/log.h"
 #include "spdk/queue.h"
 
+#include "bdev_module.h"
+
 #define SPDK_BDEV_IO_POOL_SIZE	(64 * 1024)
 #define RBUF_SMALL_POOL_SIZE	8192
 #define RBUF_LARGE_POOL_SIZE	1024

lib/bdev/bdev_module.h

@@ -0,0 +1,167 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright (C) 2008-2012 Daisuke Aoyama <aoyama@peach.ne.jp>.
+ *   Copyright (c) Intel Corporation.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/** \file
+ * Block Device Module Interface
+ */
+
+#ifndef SPDK_BDEV_MODULE_H_
+#define SPDK_BDEV_MODULE_H_
+
+#include <inttypes.h>
+#include <unistd.h>
+#include <stddef.h>  /* for offsetof */
+#include <sys/uio.h> /* for struct iovec */
+#include <stdbool.h>
+
+#include "spdk/bdev.h"
+#include "spdk/event.h"
+#include "spdk/queue.h"
+#include "spdk/scsi_spec.h"
+
+/** \page block_backend_modules Block Device Backend Modules
+
+To implement a backend block device driver, a number of functions
+dictated by struct spdk_bdev_fn_table must be provided.
+
+The module should register itself using SPDK_BDEV_MODULE_REGISTER or
+SPDK_VBDEV_MODULE_REGISTER to define the parameters for the module.
+
+Use SPDK_BDEV_MODULE_REGISTER for all block backends that are real disks.
+Any virtual backends such as RAID, partitioning, etc. should use
+SPDK_VBDEV_MODULE_REGISTER.
+
+<hr>
+
+In the module initialization code, the config file sections can be parsed to
+acquire custom configuration parameters. For example, if the config file has
+a section such as below:
+<blockquote><pre>
+[MyBE]
+  MyParam 1234
+</pre></blockquote>
+
+The value can be extracted as the example below:
+<blockquote><pre>
+struct spdk_conf_section *sp = spdk_conf_find_section(NULL, "MyBe");
+int my_param = spdk_conf_section_get_intval(sp, "MyParam");
+</pre></blockquote>
+
+The backend initialization routine also need to create "disks". A virtual
+representation of each LUN must be constructed. Mainly a struct spdk_bdev
+must be passed to the bdev database via spdk_bdev_register().
+
+*/
+
+/** Block device module */
+struct spdk_bdev_module_if {
+	/**
+	 * Initialization function for the module.  Called by the spdk
+	 * application during startup.
+	 *
+	 * Modules are required to define this function.
+	 */
+	int (*module_init)(void);
+
+	/**
+	 * Finish function for the module.  Called by the spdk application
+	 * before the spdk application exits to perform any necessary cleanup.
+	 *
+	 * Modules are not required to define this function.
+	 */
+	void (*module_fini)(void);
+
+	/**
+	 * Function called to return a text string representing the
+	 * module's configuration options for inclusion in a configuration file.
+	 */
+	void (*config_text)(FILE *fp);
+
+	/** Name for the modules being defined. */
+	const char *module_name;
+
+	/**
+	 * Returns the allocation size required for the backend for uses such as local
+	 * command structs, local SGL, iovecs, or other user context.
+	 */
+	int (*get_ctx_size)(void);
+
+	TAILQ_ENTRY(spdk_bdev_module_if) tailq;
+};
+
+
+void spdk_bdev_register(struct spdk_bdev *bdev);
+void spdk_bdev_io_get_rbuf(struct spdk_bdev_io *bdev_io, spdk_bdev_io_get_rbuf_cb cb);
+struct spdk_bdev_io *spdk_bdev_get_io(void);
+struct spdk_bdev_io *spdk_bdev_get_child_io(struct spdk_bdev_io *parent,
+		struct spdk_bdev *bdev,
+		spdk_bdev_io_completion_cb cb,
+		void *cb_arg);
+void spdk_bdev_io_complete(struct spdk_bdev_io *bdev_io,
+			   enum spdk_bdev_io_status status);
+void spdk_bdev_module_list_add(struct spdk_bdev_module_if *bdev_module);
+void spdk_vbdev_module_list_add(struct spdk_bdev_module_if *vbdev_module);
+
+static inline struct spdk_bdev_io *
+spdk_bdev_io_from_ctx(void *ctx)
+{
+	return (struct spdk_bdev_io *)
+	       ((uintptr_t)ctx - offsetof(struct spdk_bdev_io, driver_ctx));
+}
+
+#define SPDK_BDEV_MODULE_REGISTER(init_fn, fini_fn, config_fn, ctx_size_fn)			\
+	static struct spdk_bdev_module_if init_fn ## _if = {					\
+	.module_init 	= init_fn,								\
+	.module_fini	= fini_fn,								\
+	.config_text	= config_fn,								\
+	.get_ctx_size	= ctx_size_fn,                                				\
+	};  											\
+	__attribute__((constructor)) static void init_fn ## _init(void)  			\
+	{                                                           				\
+	    spdk_bdev_module_list_add(&init_fn ## _if);                  			\
+	}
+
+#define SPDK_VBDEV_MODULE_REGISTER(init_fn, fini_fn, config_fn, ctx_size_fn)			\
+	static struct spdk_bdev_module_if init_fn ## _if = {					\
+	.module_init 	= init_fn,								\
+	.module_fini	= fini_fn,								\
+	.config_text	= config_fn,								\
+	.get_ctx_size	= ctx_size_fn,                                				\
+	};  											\
+	__attribute__((constructor)) static void init_fn ## _init(void)  			\
+	{                                                           				\
+	    spdk_vbdev_module_list_add(&init_fn ## _if);                  			\
+	}
+
+#endif /* SPDK_BDEV_MODULE_H_ */

lib/bdev/malloc/Makefile

@@ -34,7 +34,7 @@
 SPDK_ROOT_DIR := $(abspath $(CURDIR)/../../..)
 include $(SPDK_ROOT_DIR)/mk/spdk.common.mk
 
-CFLAGS += $(DPDK_INC)
+CFLAGS += $(DPDK_INC) -I$(SPDK_ROOT_DIR)/lib/bdev/
 C_SRCS = blockdev_malloc.c blockdev_malloc_rpc.c
 LIBNAME = bdev_malloc
 

lib/bdev/malloc/blockdev_malloc.c

@@ -44,6 +44,8 @@
 #include "spdk/log.h"
 #include "spdk/copy_engine.h"
 
+#include "bdev_module.h"
+
 struct malloc_disk {
 	struct spdk_bdev	disk;	/* this must be the first element */
 	void 			*malloc_buf;

lib/bdev/nvme/Makefile

@@ -34,7 +34,7 @@
 SPDK_ROOT_DIR := $(abspath $(CURDIR)/../../..)
 include $(SPDK_ROOT_DIR)/mk/spdk.common.mk
 
-CFLAGS += $(DPDK_INC)
+CFLAGS += $(DPDK_INC) -I$(SPDK_ROOT_DIR)/lib/bdev/
 C_SRCS = blockdev_nvme.c
 LIBNAME = bdev_nvme
 

lib/bdev/nvme/blockdev_nvme.c

@@ -53,6 +53,8 @@
 #include "spdk/bdev.h"
 #include "spdk/nvme.h"
 
+#include "bdev_module.h"
+
 #define MAX_NVME_NAME_LENGTH 64
 
 void init_request_mempool(void);