Add fs/mmap

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3576 42af7a65-404d-4744-a932-0658087f49c3

fs/Makefile

@@ -46,14 +46,16 @@ endif
 else
 CSRCS		+= fs_open.c fs_close.c fs_read.c fs_write.c fs_ioctl.c \
 		   fs_poll.c fs_select.c fs_lseek.c fs_dup.c fs_filedup.c \
-		   fs_dup2.c fs_fcntl.c fs_filedup2.c fs_mmap.c fs_opendir.c \
+		   fs_dup2.c fs_fcntl.c fs_filedup2.c fs_opendir.c fs_closedir.c \
-		   fs_closedir.c fs_stat.c fs_readdir.c fs_seekdir.c fs_rewinddir.c \
+		   fs_stat.c fs_readdir.c fs_seekdir.c fs_rewinddir.c fs_files.c \
-		   fs_files.c fs_inode.c fs_inodefind.c fs_inodereserve.c  \
+		   fs_inode.c fs_inodefind.c fs_inodereserve.c  fs_statfs.c \
-		   fs_statfs.c fs_inoderemove.c fs_registerdriver.c fs_unregisterdriver.c \
+		   fs_inoderemove.c fs_registerdriver.c fs_unregisterdriver.c \
 		   fs_inodeaddref.c fs_inoderelease.c
 CSRCS		+= fs_registerblockdriver.c fs_unregisterblockdriver.c \
 		   fs_findblockdriver.c fs_openblockdriver.c fs_closeblockdriver.c
 
+include mmap/Make.defs
+
 ifneq ($(CONFIG_NFILE_STREAMS),0)
 CSRCS		+= fs_fdopen.c 
 endif
@@ -74,8 +76,8 @@ OBJS		= $(AOBJS) $(COBJS)
 
 BIN		= libfs$(LIBEXT)
 
-SUBDIRS		= fat romfs nxffs
+SUBDIRS		= mmap fat romfs nxffs
-VPATH		= fat:romfs:nxffs
+VPATH		= mmap:fat:romfs:nxffs
 
 all:	$(BIN)
 
@@ -91,7 +93,7 @@ $(BIN):	$(OBJS)
 	done ; )
 
 .depend: Makefile $(SRCS)
-	@$(MKDEP) --dep-path . $(FATDEPPATH) $(ROMFSDEPPATH) $(NXFFSDEPPATH) \
+	@$(MKDEP) --dep-path . $(MMAPDEPPATH) $(FATDEPPATH) $(ROMFSDEPPATH) $(NXFFSDEPPATH) \
 		$(CC) -- $(CFLAGS) -- $(SRCS) >Make.dep
 	@touch $@
 

fs/mmap/Make.defs

@@ -0,0 +1,43 @@
+############################################################################
+# fs/mmap/Make.defs
+#
+#   Copyright (C) 2011 Gregory Nutt. All rights reserved.
+#   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+# 1. Redistributions of source 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.
+#
+############################################################################
+
+ASRCS +=
+CSRCS += fs_mmap.c
+
+ifeq ($(CONFIG_FS_RAMMAP),y)
+CSRCS += fs_munmap.c fs_rammap.c
+endif
+
+MMAPDEPPATH = --dep-path mmap

fs/mmap/fs_mmap.c

@@ -1,7 +1,7 @@
 /****************************************************************************
- * fs/fs_mmap.c
+ * fs/mmap/fs_mmap.c
  *
- *   Copyright (C) 2008-2009 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2008-2009, 2011 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -57,25 +57,30 @@
  *
  * Description:
  *   NuttX operates in a flat open address space.  Therefore, it generally
- *   does not require mmap() functionality.  There is one one exception:
+ *   does not require mmap() functionality.  There are two exceptions:
- *   mmap() is the API that is used to support direct access to random
+ *
+ *   1. mmap() is the API that is used to support direct access to random
  *     access media under the following very restrictive conditions:
  *
- *   1. The filesystem supports the FIOC_MMAP ioctl command.  Any file system
+ *     a. The filesystem supports the FIOC_MMAP ioctl command.  Any file
- *      that maps files contiguously on the media should support this ioctl.
+ *        system that maps files contiguously on the media should support
- *      (vs. file system that scatter files over the media in non-contiguous
+ *        this ioctl. (vs. file system that scatter files over the media
- *      sectors).  As of this writing, ROMFS is the only file system that
+ *        in non-contiguous sectors).  As of this writing, ROMFS is the
- *      meets this requirement.
+ *        only file system that meets this requirement.
- *   2. The underly block driver supports the BIOC_XIPBASE ioctl command
+ *     b. The underlying block driver supports the BIOC_XIPBASE ioctl
- *      that maps the underlying media to a randomly accessible address. At
+ *        command that maps the underlying media to a randomly accessible
- *      present, only the RAM/ROM disk driver does this.
+ *        address. At  present, only the RAM/ROM disk driver does this.
+ *
+ *   2. If CONFIG_FS_RAMMAP is defined in the configuration, then mmap() will
+ *      support simulation of memory mapped files by copying files whole
+ *      into RAM.
  *
  * Parameters:
  *   start   A hint at where to map the memory -- ignored.  The address
- *           of the underlying media is fixed and cannot be re-mapped withou
+ *           of the underlying media is fixed and cannot be re-mapped without
  *           MMU support.
- *   length  The length of the mapping -- ignored.  The entire underlying
+ *   length  The length of the mapping.  For exception #1 above, this length
- *           media is always accessible.
+ *           ignored:  The entire underlying media is always accessible.
  *   prot    See the PROT_* definitions in sys/mman.h.
  *           PROT_NONE      - Will cause an error
  *           PROT_READ      - PROT_WRITE and PROT_EXEC also assumed
@@ -98,9 +103,9 @@
  *   fd      file descriptor of the backing file -- required.
  *   offset  The offset into the file to map
  *
- * Return:
+ * Returned Value:
- *   On success, mmap() returns a pointer to the mapped area. 
+ *   On success, mmap() returns a pointer to the mapped area. On error, the
- *   On error, the value MAP_FAILED is returned, and errno is set appropriately.
+ *   value MAP_FAILED is returned, and errno is set appropriately.
  *
  *     ENOSYS
  *       Returned if any of the unsupported mmap() features are attempted
@@ -155,9 +160,15 @@ FAR void *mmap(FAR void *start, size_t length, int prot, int flags,
   ret = ioctl(fd, FIOC_MMAP, (unsigned long)((uintptr_t)&addr));
   if (ret < 0)
     {
+#ifdef CONFIG_FS_RAMMAP
+      ret = rammap(fd, length, offset, &addr);
+      if (ret < 0)
+#endif
+        {
           fdbg("ioctl(FIOC_MMAP) failed: %d\n", errno);
           goto errout;
         }
+    }
 
   /* Return the offset address */
 
@@ -171,4 +182,3 @@ errout_with_ret:
 errout:
   return MAP_FAILED;
 }
-

fs/mmap/fs_munmap.c

@@ -0,0 +1,114 @@
+/****************************************************************************
+ * fs/mmap/fs_munmap.c
+ *
+ *   Copyright (C) 2011 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source 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/mman.h>
+
+#include <stdint.h>
+#include <errno.h>
+#include <debug.h>
+
+#include "fs_internal.h"
+
+#ifdef CONFIG_FS_RAMMAP
+
+/****************************************************************************
+ * Global Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: munmap
+ *
+ * Description:
+ *
+ *   munmap() system call deletes mappings for the specified address range.
+ *   The region is also automatically unmapped when the process is terminated.
+ *   On the other hand, closing the file descriptor does not unmap the region.
+ *
+ *   NuttX operates in a flat open address space.  Therefore, it generally
+ *   does not require mmap() and, hence, munmap functionality.  There are
+ *   two exceptions where mmap() is available:
+ *
+ *   1. mmap() is the API that is used to support direct access to random
+ *     access media under the following very restrictive conditions:
+ *
+ *     a. The filesystem supports the FIOC_MMAP ioctl command.  Any file
+ *        system that maps files contiguously on the media should support
+ *        this ioctl. (vs. file system that scatter files over the media
+ *        in non-contiguous sectors).  As of this writing, ROMFS is the
+ *        only file system that meets this requirement.
+ *     b. The underlying block driver supports the BIOC_XIPBASE ioctl
+ *        command that maps the underlying media to a randomly accessible
+ *        address. At  present, only the RAM/ROM disk driver does this.
+ *
+ *     munmap() is still not required in this first case.  In this first
+ *     The mapped address is a static address in the MCUs address space
+ *     does not need to be munmapped.  Support for munmap() in this case
+ *     provided by the simple definition in sys/mman.h:
+ *
+ *        #define munmap(start, length)
+ *
+ *   2. If CONFIG_FS_RAMMAP is defined in the configuration, then mmap() will
+ *      support simulation of memory mapped files by copying files whole
+ *      into RAM.  munmap() is required in this case to free the allocated
+ *      memory holding the shared copy of the file.
+ *
+ * Parameters:
+ *   start   The start address of the mapping to delete.  For this
+ *           simplified munmap() implementation, the *must* be the start
+ *           address of the memory region (the same address returned by
+ *           mmap()).
+ *   length  The length region to be umapped.  Ignored.  The entire underlying
+ *           media is always freed.
+ *
+ * Returned Value:
+ *   On success, munmap() returns 0, on failure -1, and errno is set
+ *   (probably to EINVAL).
+ *
+ ****************************************************************************/
+
+int munmap(FART void *start, size_t length)
+{
+#warning "Missing logic"
+  return MAP_FAILED;
+}
+
+#endif /* CONFIG_FS_RAMMAP */

fs/mmap/fs_rammap.c

@@ -0,0 +1,85 @@
+/****************************************************************************
+ * fs/mmap/fs_rammmap.c
+ *
+ *   Copyright (C) 2011 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source 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 <errno.h>
+#include <debug.h>
+
+#include "fs_internal.h"
+
+#ifdef CONFIG_FS_RAMMAP
+
+/****************************************************************************
+ * Global Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: rammmap
+ *
+ * Description:
+ *   Support simulation of memory mapped files by copying files into RAM.
+ *
+ * Parameters:
+ *   fd      file descriptor of the backing file -- required.
+ *   length  The length of the mapping.  For exception #1 above, this length
+ *           ignored:  The entire underlying media is always accessible.
+ *   offset  The offset into the file to map
+ *
+ * Returned Value:
+ *   On success, rammmap() returns a pointer to the mapped area. On error, the
+ *   value MAP_FAILED is returned, and errno is set  appropriately.
+ *
+ *     EBADF
+ *      'fd' is not a valid file descriptor.
+ *     EINVAL
+ *       'length' or 'offset' are invalid
+ *     ENOMEM
+ *       Insufficient memory is available to map the file.
+ *
+ ****************************************************************************/
+
+int rammap(int fd, size_t length, off_t offset, FAR void **addr)
+{
+#warning "Missing logic"
+  return -ENOSYS;
+}
+
+#endif /* CONFIG_FS_RAMMAP */

fs/mmap/fs_rammap.h

@@ -0,0 +1,109 @@
+/****************************************************************************
+ * fs/mmap/rammap.h
+ *
+ *   Copyright (C) 2011 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * References: Linux/Documentation/filesystems/romfs.txt
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source 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.
+ *
+ ****************************************************************************/
+
+#ifndef __FS_MMAP_RAMMAP_H
+#define __FS_MMAP_RAMMAP_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#ifdef CONFIG_FS_RAMMAP
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+/* This structure describes one file that has been copied to memory and
+ * managed as a share-able "memory mapped" file.  This functionality is
+ * intended to provide a substitute for memory mapped files for architectures
+ * that do not have MMUs and, hence, cannot support on demand paging of
+ * blocks of a file.
+ *
+ * This copied file has many of the properties of a standard memory mapped
+ * file except for all of the file must be present in memory.  This limits
+ * the size of files that may be memory mapped (especially on MCUs with
+ * no significant RAM resources).
+ */
+
+struct fs_rammap_s
+{
+};
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: rammmap
+ *
+ * Description:
+ *   Support simulation of memory mapped files by copying files into RAM.
+ *
+ * Parameters:
+ *   fd      file descriptor of the backing file -- required.
+ *   length  The length of the mapping.  For exception #1 above, this length
+ *           ignored:  The entire underlying media is always accessible.
+ *   offset  The offset into the file to map
+ *
+ * Returned Value:
+ *   On success, rammmap() returns a pointer to the mapped area. On error, the
+ *   value MAP_FAILED is returned, and errno is set  appropriately.
+ *
+ *     EBADF
+ *      'fd' is not a valid file descriptor.
+ *     EINVAL
+ *       'length' or 'offset' are invalid
+ *     ENOMEM
+ *       Insufficient memory is available to map the file.
+ *
+ ****************************************************************************/
+
+extern int rammap(int fd, size_t length, off_t offset, FAR void **addr);
+
+#endif /* CONFIG_FS_RAMMAP */
+#endif /* __FS_MMAP_RAMMAP_H */