Add find/open/close_blockdriver()

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@796 42af7a65-404d-4744-a932-0658087f49c3

fs/Makefile

@@ -52,6 +52,7 @@ CSRCS		+= fs_open.c fs_close.c fs_read.c fs_write.c fs_ioctl.c fs_lseek.c \
 		   fs_inodeaddref.c fs_inoderelease.c
 ifneq ($(CONFIG_DISABLE_MOUNTPOINT),y)
 CSRCS		+= fs_registerblockdriver.c fs_unregisterblockdriver.c \
+		   fs_findblockdriver.c fs_openblockdriver.c fs_closeblockdriver.c \
 		   fs_mount.c fs_umount.c \
 		   fs_fsync.c fs_unlink.c fs_rename.c \
 		   fs_mkdir.c fs_rmdir.c

fs/fs_closeblockdriver.c

+/****************************************************************************
+ * fs/fs_closeblockdriver.c
+ *
+ *   Copyright (C) 2008 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in pathname and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of pathname code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ * 3. Neither the name NuttX 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.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <debug.h>
+#include <errno.h>
+#include <nuttx/fs.h>
+
+#include "fs_internal.h"
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: close_blockdriver
+ *
+ * Description:
+ *   Call the close method and release the inode
+ *
+ * Inputs:
+ *   inode - reference to the inode of a block driver opened by open_blockdriver
+ *
+ * Return:
+ *   Returns zero on success or a negated errno on failure:
+ *
+ *   EINVAL  - inode is NULL
+ *   ENOTBLK - The inode is not a block driver
+ *
+ ****************************************************************************/
+
+int close_blockdriver(FAR struct inode *inode)
+{
+  int ret = 0; /* Assume success */
+
+  /* Sanity checks */
+
+  if (!inode || !inode->u.i_bops)
+    {
+      ret = -EINVAL;
+      goto errout;
+    }
+
+  /* Verify that the inode is a block driver. */
+
+  if (!INODE_IS_BLOCK(inode))
+    { 
+      fdbg("%s is not a block driver\n", pathname);
+      ret = -ENOTBLK;
+      goto errout;
+   }
+
+  /* Close the block driver.  Not that no mutually exclusive access
+   * to the driver is enforced here.  That must be done in the driver
+   * if needed.
+   */
+
+  if (inode->u.i_bops->close)
+    {
+      ret = inode->u.i_bops->close(inode);
+    }
+
+  /* Then release the reference on the inode */
+
+  inode_release(inode);
+errout:
+  return ret;
+}

fs/fs_findblockdriver.c

+/****************************************************************************
+ * fs/fs_openblockdriver.c
+ *
+ *   Copyright (C) 2008 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in pathname and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of pathname code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ * 3. Neither the name NuttX 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.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <sys/mount.h>
+#include <debug.h>
+#include <errno.h>
+#include <nuttx/fs.h>
+
+#include "fs_internal.h"
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: find_blockdriver
+ *
+ * Description:
+ *   Return the inode of the block driver specified by 'pathname'
+ *
+ * Inputs:
+ *   pathname - the full path to the block driver to be located
+ *   mountflags - if MS_RDONLY is set, then driver must support write
+ *     operations (see include/sys/mount.h)
+ *   ppinode - address of the location to return the inode reference
+ *
+ * Return:
+ *   Returns zero on success or a negated errno on failure:
+ *
+ *   EINVAL  - pathname or pinode is NULL
+ *   ENOENT  - No block driver of this name is registered
+ *   ENOTBLK - The inode associated with the pathname is not a block driver
+ *   EACCESS - The MS_RDONLY option was not set but this driver does not
+ *     support write access
+ *
+ ****************************************************************************/
+
+int find_blockdriver(FAR const char *pathname, int mountflags, FAR struct inode **ppinode)
+{
+  FAR struct inode *inode;
+  int ret = 0; /* Assume success */
+
+  /* Sanity checks */
+
+  if (!pathname || !ppinode)
+    {
+      ret = -EINVAL;
+      goto errout;
+    }
+
+  /* Find the inode registered with this pathname */
+
+  inode = inode_find(pathname, NULL);
+  if (!inode)
+    {
+      fdbg("Failed to find %s\n", pathname);
+      ret = -ENOENT;
+      goto errout;
+    }
+
+  /* Verify that the inode is a block driver. */
+
+  if (!INODE_IS_BLOCK(inode))
+    { 
+      fdbg("%s is not a block driver\n", pathname);
+      ret = -ENOTBLK;
+      goto errout_with_inode;
+   }
+
+  /* Make sure that the inode supports the requested access */
+
+  if (!inode->u.i_bops || !inode->u.i_bops->read ||
+      (!inode->u.i_bops->write && (mountflags & MS_RDONLY) == 0))
+    {
+      fdbg("%s does not support requested access\n", pathname);
+      ret = -EACCES;
+      goto errout_with_inode;
+    }
+
+  *ppinode = inode;
+  return OK;
+
+errout_with_inode:
+  inode_release(inode);
+errout:
+  return ret;
+}

fs/fs_internal.h

@@ -205,13 +205,27 @@ EXTERN void inode_addref(FAR struct inode *inode);
 
 EXTERN void inode_release(FAR struct inode *inode);
 
-/* fs_files.c ***************************************************************/
+/* fs_files.c ****************************************************************/
 
 EXTERN void weak_function files_initialize(void);
 EXTERN int  files_allocate(FAR struct inode *inode, int oflags, off_t pos);
 EXTERN int  files_close(int filedes);
 EXTERN void files_release(int filedes);
 
+/* fs_findblockdriver.c ******************************************************/
+
+EXTERN int find_blockdriver(FAR const char *pathname, int mountflags,
+                            FAR struct inode **ppinode);
+
+/* fs_openblockdriver.c ******************************************************/
+
+EXTERN int open_blockdriver(FAR const char *pathname, int mountflags,
+                            FAR struct inode **ppinode);
+
+/* fs_closeblockdriver.c *****************************************************/
+
+EXTERN int close_blockdriver(FAR struct inode *inode);
+
 #undef EXTERN
 #if defined(__cplusplus)
 }

fs/fs_mount.c

@@ -41,8 +41,10 @@
 #include <sys/types.h>
 #include <sys/mount.h>
 #include <string.h>
+#include <debug.h>
 #include <errno.h>
 #include <nuttx/fs.h>
+
 #include "fs_internal.h"
 
 /* At least one filesystem must be defined, or this file will not compile.
@@ -160,37 +162,23 @@ int mount(const char *source, const char *target,
     }
 
   /* Find the specified filesystem */
+
   mops = mount_findfs(filesystemtype);
   if (!mops)
     {
+      fdbg("Failed to find filsystem %s\n", filesystemtype);
       errcode = ENODEV;
       goto errout;
     }
 
-  /* Find the block driver */
-
-  blkdrvr_inode = inode_find(source, NULL);
-  if (!blkdrvr_inode)
-    {
-      errcode = ENOENT;
-      goto errout;
-    }
-
-  /* Verify that the inode is a block driver. */
-
-  if (!INODE_IS_BLOCK(blkdrvr_inode))
-    { 
-      errcode = ENOTBLK;
-      goto errout_with_blkdrvr;
-   }
-
-  /* Make sure that the inode supports the requested access */
+  /* Find the inode of the block driver indentified by 'source' */
 
-  if (!blkdrvr_inode->u.i_bops->read ||
-      (!blkdrvr_inode->u.i_bops->write && (mountflags & MS_RDONLY) == 0))
+  status = find_blockdriver(source, mountflags, &blkdrvr_inode);
+  if (status < 0)
     {
-      errcode = EACCES;
-      goto errout_with_blkdrvr;
+       fdbg("Failed to find block driver %s\n", source);
+       errcode = -status;
+       goto errout;
     }
 
   /* Insert a dummy node -- we need to hold the inode semaphore
@@ -205,6 +193,7 @@ int mount(const char *source, const char *target,
        * one is that the inode already exists.
        */
 
+      fdbg("Failed to reserve inode\n");
       errcode = EBUSY;
       goto errout_with_semaphore;
     }
@@ -218,6 +207,7 @@ int mount(const char *source, const char *target,
     {
       /* The filesystem does not support the bind operation ??? */
 
+      fdbg("Filesystem does not support bind\n");
       errcode = EINVAL;
       goto errout_with_mountpt;
     }
@@ -233,8 +223,9 @@ int mount(const char *source, const char *target,
   {
       /* The inode is unhappy with the blkdrvr for some reason */
 
+      fdbg("Bind method failed: %d\n", status);
       errcode = -status;
-      goto errout_with_blkdrvr2;
+      goto errout_with_blkdrvr;
   }
 
   /* We have it, now populate it with driver specific information. */
@@ -259,20 +250,15 @@ int mount(const char *source, const char *target,
 
   /* A lot of goto's!  But they make the error handling much simpler */
 
- errout_with_blkdrvr2:
+errout_with_blkdrvr:
   inode_release(blkdrvr_inode);
-
- errout_with_mountpt:
+errout_with_mountpt:
   inode_release(mountpt_inode);
-
- errout_with_semaphore:
+errout_with_semaphore:
   inode_semgive();
-
- errout_with_blkdrvr:
   inode_release(blkdrvr_inode);
-
- errout:
-  *get_errno_ptr() = errcode;
+errout:
+  errno = errcode;
   return ERROR;
 }
 

fs/fs_openblockdriver.c

+/****************************************************************************
+ * fs/fs_openblockdriver.c
+ *
+ *   Copyright (C) 2008 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in pathname and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of pathname code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ * 3. Neither the name NuttX 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.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <debug.h>
+#include <errno.h>
+#include <nuttx/fs.h>
+
+#include "fs_internal.h"
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: open_blockdriver
+ *
+ * Description:
+ *   Return the inode of the block driver specified by 'pathname'
+ *
+ * Inputs:
+ *   pathname - the full path to the block driver to be opened
+ *   mountflags - if MS_RDONLY is set, then driver must support write
+ *     operations (see include/sys/mount.h)
+ *   ppinode - address of the location to return the inode reference
+ *
+ * Return:
+ *   Returns zero on success or a negated errno on failure:
+ *
+ *   EINVAL  - pathname or pinode is NULL
+ *   ENOENT  - No block driver of this name is registered
+ *   ENOTBLK - The inode associated with the pathname is not a block driver
+ *   EACCESS - The MS_RDONLY option was not set but this driver does not
+ *     support write access
+ *
+ ****************************************************************************/
+
+int open_blockdriver(FAR const char *pathname, int mountflags, FAR struct inode **ppinode)
+{
+  FAR struct inode *inode;
+  int ret;
+
+  /* Minimal sanity checks */
+
+  if (!ppinode)
+    {
+      ret = -EINVAL;
+      goto errout;
+    }
+
+  /* Find the inode associated with this block driver name.  find_blockdriver
+   * will perform all additional error checking.
+   */
+
+  ret = find_blockdriver(pathname, mountflags, &inode);
+  if (ret < 0)
+    {
+      fdbg("Failed to file %s block driver\n", pathname);
+      goto errout;
+    }
+
+  /* Open the block driver.  Note that no mutually exclusive access
+   * to the driver is enforced here.  That must be done in the driver
+   * if needed.
+   */
+
+  if (inode->u.i_bops->open)
+    {
+      ret = inode->u.i_bops->open(inode);
+      if (ret < 0)
+        {
+          fdbg("%s driver open failed\n", pathname);
+          goto errout_with_inode;
+        }
+    }
+
+  *ppinode = inode;
+  return OK;
+
+errout_with_inode:
+  inode_release(inode);
+errout:
+  return ret;
+}

fs/fs_telldir.c

-/************************************************************
- * fs_telldir.c
+/****************************************************************************
+ * fs/fs_telldir.c
  *
- *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007, 2008 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -14,7 +14,7 @@
  *    notice, this list of conditions and the following disclaimer in
  *    the documentation and/or other materials provided with the
  *    distribution.
- * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ * 3. Neither the name NuttX nor the names of its contributors may be
  *    used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
@@ -31,11 +31,11 @@
  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  *
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Included Files
- ************************************************************/
+ ****************************************************************************/
 
 #include <nuttx/config.h>
 #include <sys/types.h>
@@ -44,15 +44,15 @@
 #include <nuttx/fs.h>
 #include "fs_internal.h"
 
-/************************************************************
+/****************************************************************************
  * Private Functions
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Public Functions
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Name: telldir
  *
  * Description:
@@ -70,7 +70,7 @@
  *
  *   EBADF - Invalid directory stream descriptor dir
  *
- ************************************************************/
+ ****************************************************************************/
 
 off_t telldir(FAR DIR *dirp)
 {