More NXFFS logic

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3537 42af7a65-404d-4744-a932-0658087f49c3

11 files changed, 1144 insertions, 51 deletions

diff --git a/apps/namedapp/binfs.c b/apps/namedapp/binfs.c
index a2f14dd75..106c1444c 100644
--- a/apps/namedapp/binfs.c
+++ b/apps/namedapp/binfs.c
@@ -4,8 +4,6 @@
  *   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:
@@ -388,11 +386,10 @@ static int binfs_readdir(struct inode *mountpt, struct fs_dirent_s *dir)
       index++;
 
       /* Set up the next directory entry offset.  NOTE that we could use the
-       * standard fr_curroffset instead of our own private fr_curroffset.
+       * standard f_pos instead of our own private fb_index.
        */
 
       dir->u.binfs.fb_index      = index;
-      dir->u.romfs.fr_curroffset = index;
       ret                        = OK;
     }
 
@@ -423,7 +420,6 @@ static int binfs_rewinddir(struct inode *mountpt, struct fs_dirent_s *dir)
   binfs_semtake(bm);
 
   dir->u.binfs.fb_index      = 0;
-  dir->u.romfs.fr_curroffset = 0;
 
   binfs_semgive(bm);
   return OK;
diff --git a/nuttx/fs/nxffs/Make.defs b/nuttx/fs/nxffs/Make.defs
index 23e9d3ec2..558fd6be6 100644
--- a/nuttx/fs/nxffs/Make.defs
+++ b/nuttx/fs/nxffs/Make.defs
@@ -36,7 +36,8 @@
 ifeq ($(CONFIG_FS_NXFFS),y)
 ASRCS +=
 CSRCS += nxffs_block.c nxffs_blockstats.c nxffs_cache.c \
-		nxffs_initialize.c nxffs_inode.c nxffs_reformat.c nxffs_util.c
+		 nxffs_initialize.c nxffs_inode.c nxffs_open.c nxffs_reformat.c \
+		 nxffs_stat.c nxffs_unlink.c nxffs_util.c
 
 # Argument for dependency checking
 
diff --git a/nuttx/fs/nxffs/nxffs.h b/nuttx/fs/nxffs/nxffs.h
index 13f93644e..091260552 100644
--- a/nuttx/fs/nxffs/nxffs.h
+++ b/nuttx/fs/nxffs/nxffs.h
@@ -169,14 +169,6 @@
 #define NXFFS_MAGICSIZE	          4
 
 /* Internal definitions *****************************************************/
-/* Values for volume flags */
-
-#define VOL_FLAGS_WRITER          (1 << 0) /* Only one writer of the volune */
-
-#define VOL_FLAGS_SET(p,f)        ((p)->flags &= ~(f))
-#define VOL_FLAGS_CLEAR(p,f)      ((p)->flags |= (f))
-#define VOL_FLAGS_TEST(p,f)       (((p)->flags & (f)) == 0)
-
 /* If we encounter this number of erased bytes, we assume that all of the
  * flash beyond this point is erased.
  */
@@ -309,10 +301,6 @@ struct nxffs_blkstats_s
  * Public Variables
  ****************************************************************************/
 
-/* A singly-linked list of open files */
-
-extern struct nxffs_ofile_s *g_ofiles;
-
 /* The magic number that appears that the beginning of each NXFFS (logical)
  * block
  */
@@ -420,6 +408,28 @@ extern int nxffs_rdcache(FAR struct nxffs_volume_s *volume, off_t block,
                          uint8_t nblocks);
 
 /****************************************************************************
+ * Name: nxffs_wrcache
+ *
+ * Description:
+ *   Write one or more logical blocks from the volume cache memory.
+ *
+ * Input Parameters:
+ *   volume - Describes the current volume
+ *   block  - The first logical block to write
+ *   nblocks - The number of logical blocks to be write.
+ *
+ * Returned Value:
+ *   Negated errnos are returned only in the case of MTD reported failures.
+ *   Nothing in the volume data itself will generate errors.
+ *
+ * Defined in nxffs_cache.c
+ *
+ ****************************************************************************/
+
+extern int nxffs_wrcache(FAR struct nxffs_volume_s *volume, off_t block,
+                         uint8_t nblocks);
+
+/****************************************************************************
  * Name: nxffs_ioseek
  *
  * Description:
@@ -553,7 +563,7 @@ extern int nxffs_nextentry(FAR struct nxffs_volume_s *volume, off_t offset,
 
 extern int nxffs_findinode(FAR struct nxffs_volume_s *volume,
                            FAR const char *name,
-                           struct nxffs_entry_s *entry);
+                           FAR struct nxffs_entry_s *entry);
 
 /****************************************************************************
  * Name: nxffs_verifyblock
@@ -645,6 +655,46 @@ extern int nxffs_blockstats(FAR struct nxffs_volume_s *volume,
 extern int nxffs_reformat(FAR struct nxffs_volume_s *volume);
 
 /****************************************************************************
+ * Name: nxffs_findofile
+ *
+ * Description:
+ *   Search the list of already opened files to see if the inode of this
+ *   name is one of the opened files.
+ *
+ * Input Parameters:
+ *   name - The name of the inode to check.
+ *
+ * Returned Value:
+ *   If an inode of this name is found in the list of opened inodes, then
+ *   a reference to the open file structure is returned.  NULL is returned
+ *   otherwise.
+ *
+ * Defined in nxffs_open.c
+ *
+ ****************************************************************************/
+
+extern FAR struct nxffs_ofile_s *nxffs_findofile(FAR const char *name);
+
+/****************************************************************************
+ * Name: nxffs_rminode
+ *
+ * Description:
+ *   Remove an inode from FLASH.  This is the internal implementation of
+ *   the file system unlinke operation.
+ *
+ * Input Parameters:
+ *   volume - Describes the NXFFS volume.
+ *   name - the name of the inode to be deleted.
+ *
+ * Returned Value:
+ *   Zero is returned if the inode is successfully deleted.  Otherwise, a
+ *   negated errno value is returned indicating the nature of the failure.
+ *
+ ****************************************************************************/
+
+extern int nxffs_rminode(FAR struct nxffs_volume_s *volume, FAR const char *name);
+
+/****************************************************************************
  * Standard mountpoint operation methods
  *
  * Description:
diff --git a/nuttx/fs/nxffs/nxffs_cache.c b/nuttx/fs/nxffs/nxffs_cache.c
index 0e7cff256..a2774ddfd 100644
--- a/nuttx/fs/nxffs/nxffs_cache.c
+++ b/nuttx/fs/nxffs/nxffs_cache.c
@@ -116,6 +116,32 @@ int nxffs_rdcache(FAR struct nxffs_volume_s *volume, off_t block,
 }
 
 /****************************************************************************
+ * Name: nxffs_wrcache
+ *
+ * Description:
+ *   Write one or more logical blocks from the volume cache memory.
+ *
+ * Input Parameters:
+ *   volume - Describes the current volume
+ *   block  - The first logical block to write
+ *   nblocks - The number of logical blocks to be write.
+ *
+ * Returned Value:
+ *   Negated errnos are returned only in the case of MTD reported failures.
+ *   Nothing in the volume data itself will generate errors.
+ *
+ * Defined in nxffs_cache.c
+ *
+ ****************************************************************************/
+
+int nxffs_wrcache(FAR struct nxffs_volume_s *volume, off_t block,
+                  uint8_t nblocks)
+{
+#warning "Missing logic"
+  return OK;
+}
+
+/****************************************************************************
  * Name: nxffs_ioseek
  *
  * Description:
diff --git a/nuttx/fs/nxffs/nxffs_initialize.c b/nuttx/fs/nxffs/nxffs_initialize.c
index f473d55c5..8d96ffa15 100644
--- a/nuttx/fs/nxffs/nxffs_initialize.c
+++ b/nuttx/fs/nxffs/nxffs_initialize.c
@@ -103,10 +103,6 @@ const struct mountpt_operations nxffs_operations =
  * Public Variables
  ****************************************************************************/
 
-/* A singly-linked list of open files */
-
-struct nxffs_ofile_s *g_ofiles;
-
 /* The magic number that appears that the beginning of each NXFFS (logical)
  * block
  */
@@ -229,9 +225,14 @@ int nxffs_initialize(FAR struct mtd_dev_s *mtd, off_t start, off_t nblocks)
 #endif
     }
 
-  /* Return success */
+  /* Get the file system limits */
 
-  return OK;
+  ret = nxffs_limits(volume);
+  if (ret == OK)
+    {
+      return OK;
+    }
+  fdbg("Failed to calculate file system limits: %d\n", -ret);
 
 errout_with_iobuffer:
   kfree(volume->cache);
@@ -267,6 +268,135 @@ errout:
 
 int nxffs_limits(FAR struct nxffs_volume_s *volume)
 {
-#warning "Missing Logic"
+  FAR struct nxffs_entry_s entry;
+  off_t block;
+  off_t offset;
+  bool noinodes = false;
+  int nerased;
+  int ret;
+
+  /* Get the offset to the first valid block on the FLASH */
+
+  block = 0;
+  ret = nxffs_validblock(volume, &block);
+  if (ret < 0)
+    {
+      fdbg("Failed to find a valid block: %d\n", -ret);
+      return ret;
+    }
+
+  /* Then find the first valid inode in or beyond the first valid block */
+
+  offset = block * volume->geo.blocksize;
+  ret = nxffs_nextentry(volume, offset, &entry);
+  if (ret < 0)
+    {
+      /* The value -ENOENT is special.  This simply means that the FLASH
+       * was searched to the end and no valid inode was found... the file
+       * system is empty (or, in more perverse cases, all inodes are
+       * deleted or corrupted).
+       */
+
+      if (ret != -ENOENT)
+        {
+          fdbg("nxffs_nextentry failed: %d\n", -ret);
+          return ret;
+        }
+
+      /* Set a flag the just indicates that no inodes were found.  Later,
+       * we will set the location of the first inode to be the same as
+       * the location of the free FLASH region.
+       */
+
+      fvdbg("No inodes found\n");
+      noinodes = true;
+    }
+  else
+    {
+      /* Save the offset to the first inode */
+
+      volume->inoffset = entry.hoffset;
+      fvdbg("First inode at offset %d\n", volume->inoffset);
+
+      /* Discard this entry and set the next offset using the rw data
+       * length as the offset increment.  This is, of course, not accurate
+       * because it does not account for the data headers that enclose the
+       * data.  But it is guaranteed to be less than or equal to the
+       * correct offset and, hence, better then searching byte-for-byte.
+       */
+
+      offset = entry.doffset + entry.datlen;
+      nxffs_freeentry(&entry);
+    }
+
+  /* Now, search for the last valid entry */
+
+  if (!noinodes)
+    {
+      while ((ret = nxffs_nextentry(volume, offset, &entry)) == OK)
+        {
+          /* Discard the entry and guess the next offset (see comments above). */
+
+          offset = entry.doffset + entry.datlen;
+          nxffs_freeentry(&entry);    
+        }
+      fvdbg("Last inode before offset %d\n", offset);
+    }
+
+  /* No inodes were found after this offset.  Now search for a block of
+   * erased flash.
+   */
+
+  nxffs_ioseek(volume, offset);
+  nerased = 0;
+  for (;;)
+    {
+      int ch = nxffs_getc(volume);
+      if (ch < 0)
+        {
+          /* Failed to read the next byte... this could mean that the FLASH
+           * is full?
+           */
+
+          fvdbg("nxffs_getc failed: %d\n", -ch);
+          return ch;
+        }
+
+      /* Check for another erased byte */
+
+      else if (ch == CONFIG_NXFFS_ERASEDSTATE)
+        {
+          /* If we have encountered NXFFS_NERASED number of consecutive
+           * erased bytes, then presume we have reached the end of valid
+           * data.
+           */
+
+          if (++nerased >= NXFFS_NERASED)
+            {
+              /* Okay.. we have a long stretch of erased FLASH in a valid
+               * FLASH block.  Let's say that this is the beginning of
+               * the free FLASH region.
+               */
+
+              volume->froffset = offset;
+              fvdbg("Free FLASH region begins at offset: %d\n", volume->froffset);
+              if (noinodes)
+                {
+                  volume->inoffset = offset;
+                  fvdbg("First inode at offset %d\n", volume->inoffset);
+                }
+              return OK;
+            }
+        }
+      else
+        {
+          offset += nerased + 1;
+          nerased = 0;
+        }
+    }
+
+  /* Won't get here */
+
+  return OK;
 }
 
diff --git a/nuttx/fs/nxffs/nxffs_inode.c b/nuttx/fs/nxffs/nxffs_inode.c
index a0b2fc0ef..ae61c9d24 100644
--- a/nuttx/fs/nxffs/nxffs_inode.c
+++ b/nuttx/fs/nxffs/nxffs_inode.c
@@ -325,7 +325,7 @@ int nxffs_nextentry(FAR struct nxffs_volume_s *volume, off_t offset,
  ****************************************************************************/
 
 int nxffs_findinode(FAR struct nxffs_volume_s *volume, FAR const char *name,
-                    struct nxffs_entry_s *entry)
+                    FAR struct nxffs_entry_s *entry)
 {
   off_t offset;
   int ret;
@@ -364,9 +364,9 @@ int nxffs_findinode(FAR struct nxffs_volume_s *volume, FAR const char *name,
       /* Discard this entry and try the next one.  Here we set the
        * next offset using the raw data length as the offset
        * increment.  This is, of course, not accurate because it
-       * does not account for the data headers that inclose the
+       * does not account for the data headers that enclose the
        * data.  But it is guaranteed to be less than or equal to
-       * the correct offset and, hence, better then seraching
+       * the correct offset and, hence, better then searching
        * byte-for-byte.
        */
 
diff --git a/nuttx/fs/nxffs/nxffs_open.c b/nuttx/fs/nxffs/nxffs_open.c
new file mode 100644
index 000000000..a7caebca5
--- /dev/null
+++ b/nuttx/fs/nxffs/nxffs_open.c
@@ -0,0 +1,521 @@
+/****************************************************************************
+ * fs/nxffs/nxffs_open.c
+ *
+ *   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.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <string.h>
+#include <fcntl.h>
+#include <assert.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <nuttx/kmalloc.h>
+#include <nuttx/fs.h>
+#include <nuttx/mtd.h>
+
+#include "nxffs.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/* A singly-linked list of open files */
+
+static struct nxffs_ofile_s *g_ofiles;
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: nxffs_create
+ *
+ * Description:
+ *   Create a file:  Verify the sufficient space exists at the end of the
+ *   FLASH.  If so, then write then update entry in preparation for writing.
+ *
+ ****************************************************************************/
+
+static inline int nxffs_create(FAR struct nxffs_volume_s *volume,
+                               FAR const char *name, mode_t mode,
+                               FAR struct nxffs_ofile_s **ppofile)
+{
+#warning "Check if too close to end of block for whole header"
+  return OK;
+}
+
+/****************************************************************************
+ * Name: nxffs_wropen
+ *
+ * Description:
+ *   Handle opening for writing.  Only a single writer is permitted and only
+ *   file creation is supported.
+ *
+ ****************************************************************************/
+
+static inline int nxffs_wropen(FAR struct nxffs_volume_s *volume,
+                               FAR const char *name, mode_t mode,
+                               FAR struct nxffs_ofile_s **ppofile)
+{
+  FAR struct nxffs_wrfile_s *wrfile;
+  FAR struct nxffs_entry_s entry;
+  int ret;
+
+  /* Limitation: Only a single writer is permitted.  Writing may involve
+   * extension of the file system in FLASH.  Since files are contiguous
+   * in FLASH, only a single file may be extending the FLASH region.
+   */
+
+  if (volume->wrbusy)
+    {
+      fdbg("There is already a file writer\n");
+      return -ENOSYS;
+    }
+
+  /* Check if the file exists */
+
+  ret = nxffs_findinode(volume, name, &entry);
+  if (ret == OK)
+    {
+      /* It exists.  It would be an error if we are asked to create it
+       * exclusively.
+       */
+
+      if ((mode & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL))
+        {
+          fdbg("File exists, can't create O_EXCL\n");
+          return -EEXIST;
+        }
+
+      /* Were we asked to truncate the file?  NOTE: Don't truncate the
+       * file if we were not also asked to created it.  See below...
+       * we will not re-create the file unless O_CREAT is also specified.
+       */
+
+      else if ((mode & (O_CREAT|O_TRUNC)) == (O_CREAT|O_TRUNC))
+        {
+          /* Just remove the file and fall through to re-create it */
+#warning "Should defer file removal until new file successfully written"
+
+          ret = nxffs_rminode(volume, name);
+          if (ret < 0)
+            {
+              fdbg("nxffs_rminode failed: %d\n", -ret);
+              return ret;
+            }
+        }
+
+      /* The file exists and we were not asked to truncate (and recreate) it.
+       * Limitation: Cannot write to existing files.
+       */
+
+      else
+        {
+          fdbg("File %s exists and we were not asked to truncate it\n");
+          return -ENOSYS;
+        }
+    }
+
+  /* Okay, the file is not open and does not exists (maybe because we deleted
+   * it).  Now, make sure that we were asked to created it.
+   */
+
+  if ((mode & O_CREAT) == 0)
+    {
+      fdbg("Not asked to create the file\n");
+      return -ENOENT;
+    }
+
+  /* Yes.. Create a new structure that will describe the state of this open
+   * file.  NOTE that a special variant of the open file structure is used
+   * that includes additional information to support the write operation.
+   */
+
+  wrfile = (FAR struct nxffs_wrfile_s *)kzalloc(sizeof(struct nxffs_wrfile_s));
+  if (!wrfile)
+    {
+      return -ENOMEM;
+    }
+
+  /* Initialize the open file state structure */
+
+  wrfile->ofile.crefs  = 1;
+
+  /* Allocate FLASH memory for the file and set up for the write */
+
+#warning "Missing Logic"
+
+  /* Add the open file structure to the head of the list of open files */
+
+  wrfile->ofile.flink = g_ofiles;
+  g_ofiles            = &wrfile->ofile;
+
+  /* Indicate that the volume is open for writing and return the open file
+   * instance.
+   */
+
+  volume->wrbusy = 1;
+  *ppofile = &wrfile->ofile;
+  return OK;
+}
+
+/****************************************************************************
+ * Name: nxffs_rdopen
+ *
+ * Description:
+ *   Open an existing file for reading.
+ *
+ ****************************************************************************/
+
+static inline int nxffs_rdopen(FAR struct nxffs_volume_s *volume,
+                               FAR const char *name,
+                               FAR struct nxffs_ofile_s **ppofile)
+{
+  FAR struct nxffs_ofile_s *ofile;
+  int ret;
+
+  /* Check if the file has already been opened (for reading) */
+
+  ofile = nxffs_findofile(name);
+  if (ofile)
+    {
+      /* The file is already open.
+       * Limitation:  Files cannot be open both for reading and writing.
+       */
+
+      if ((ofile->mode & O_WROK) != 0)
+        {
+          fdbg("File is open for writing\n");
+          return -ENOSYS;
+        }
+
+      /* Just increment the reference count on the ofile */
+
+      ofile->crefs++;
+      fdbg("crefs: %d\n", ofile->crefs);
+    }
+
+  /* The file has not yet been opened.
+   * Limitation: The file must exist.  We do not support creation of files
+   * read-only.
+   */
+
+  else
+    {
+      /* Not already open.. create a new open structure */
+ 
+      ofile = (FAR struct nxffs_ofile_s *)kzalloc(sizeof(struct nxffs_ofile_s));
+      if (!ofile)
+        {
+          fdbg("ofile allocation failed\n");
+          return -ENOMEM;
+        }
+
+      /* Initialize the open file state structure */
+
+      ofile->crefs  = 1;
+
+      /* Find the file on this volume associated with this file name */
+
+      ret = nxffs_findinode(volume, name, &ofile->entry);
+      if (ret != OK)
+        {
+          fdbg("Inode '%s' not found: %d\n", name, -ret);
+          kfree(ofile);
+          return ret;
+        }
+
+      /* Add the open file structure to the head of the list of open files */
+
+      ofile->flink = g_ofiles;
+      g_ofiles     = ofile;
+    }
+
+  /* Return the open file state structure */
+
+  *ppofile = ofile;
+  return OK;
+}
+
+/****************************************************************************
+ * Name: nxffs_freeofile
+ ****************************************************************************/
+
+static inline void nxffs_freeofile(FAR struct nxffs_ofile_s *ofile)
+{
+  FAR struct nxffs_ofile_s *prev;
+  FAR struct nxffs_ofile_s *curr;
+
+  /* Find the open file structure to be removed */
+
+  for (prev = NULL, curr = g_ofiles;
+       curr && curr != ofile;
+       prev = curr, curr = curr->flink);
+
+  /* Was it found? */
+
+  if (curr)
+    {
+      /* Yes.. at the head of the list? */
+
+      if (prev)
+        {
+          prev->flink = ofile->flink;
+        }
+      else
+        {
+          g_ofiles = ofile->flink;
+        }
+
+      /* Then free the open file */
+
+      nxffs_freeentry(&ofile->entry);
+      kfree(ofile);
+    }
+  else
+    {
+      fdbg("ERROR: Open inode %p not found\n", ofile);
+    }
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: nxffs_findofile
+ *
+ * Description:
+ *   Search the list of already opened files to see if the inode of this
+ *   name is one of the opened files.
+ *
+ * Input Parameters:
+ *   name - The name of the inode to check.
+ *
+ * Returned Value:
+ *   If an inode of this name is found in the list of opened inodes, then
+ *   a reference to the open file structure is returned.  NULL is returned
+ *   otherwise.
+ *
+ ****************************************************************************/
+
+FAR struct nxffs_ofile_s *nxffs_findofile(FAR const char *name)
+{
+  FAR struct nxffs_ofile_s *ofile;
+
+  /* Check every open file.  Note that the volume exclsem protects the
+   * list of open files.
+   */
+
+  for (ofile = g_ofiles; ofile; ofile = ofile->flink)
+    {
+      /* Check for a name match */
+
+      if (strcmp(name, ofile->entry.name) == 0)
+        {
+          return ofile;
+        }
+    }
+
+  return NULL;
+}
+
+/****************************************************************************
+ * Name: nxffs_open
+ *
+ * Description:
+ *   This is the standard mountpoint open method.
+ *
+ ****************************************************************************/
+
+int nxffs_open(FAR struct file *filep, FAR const char *relpath,
+               int oflags, mode_t mode)
+{
+  FAR struct nxffs_volume_s *volume;
+  FAR struct nxffs_ofile_s *ofile = NULL;
+  int ret;
+
+  fvdbg("Open '%s'\n", relpath);
+
+  /* Sanity checks */
+
+  DEBUGASSERT(filep->f_priv == NULL && filep->f_inode != NULL);
+
+  /* Get the mountpoint private data from the NuttX inode reference in the
+   * file structure
+   */
+
+  volume = (FAR struct nxffs_volume_s*)filep->f_inode->i_private;
+  DEBUGASSERT(volume != NULL);
+
+  /* Get exclusive access to the volume.  Note that the volume exclsem
+   * protects the open file list.
+   */
+
+  ret = sem_wait(&volume->exclsem);
+  if (ret != OK)
+    {
+      ret = -errno;
+      fdbg("sem_wait failed: %d\n", ret);
+      goto errout;
+    }
+
+#ifdef CONFIG_FILE_MODE
+#  warning "Missing check for privileges based on inode->i_mode"
+#endif
+
+  /* Limitation:  A file must be opened for reading or writing, but not both.
+   * There is no general for extending the size of of a file.  Extending the
+   * file size of possible if the file to be extended is the last in the
+   * sequence on FLASH, but since that case is not the general case, no file
+   * extension is supported.
+   */
+
+   switch (mode & (O_WROK|O_RDOK))
+     {
+       case 0:
+       default:
+         fdbg("One of O_WRONLY/O_RDONLY must be provided\n");
+         ret = -EINVAL;
+         goto errout_with_semaphore;
+
+       case O_WROK:
+         ret = nxffs_wropen(volume, relpath, mode, &ofile);
+         break;
+
+       case O_RDOK:
+         ret = nxffs_rdopen(volume, relpath, &ofile);
+         break;
+
+       case O_WROK|O_RDOK:
+         fdbg("O_RDWR is not supported\n");
+         ret = -ENOSYS;
+         goto errout_with_semaphore;
+     }
+
+  /* Save open-specific state in filep->f_priv */
+
+  filep->f_priv = ofile;
+  ret = OK;
+
+errout_with_semaphore:
+  sem_post(&volume->exclsem);
+errout:
+  return ret;
+}
+
+/****************************************************************************
+ * Name: nxffs_close
+ *
+ * Description:
+ *   This is the standard mountpoint close method.
+ *
+ ****************************************************************************/
+
+int nxffs_close(FAR struct file *filep)
+{
+  FAR struct nxffs_volume_s *volume;
+  FAR struct nxffs_ofile_s *ofile;
+  int ret = -ENOSYS;
+
+  fvdbg("Closing\n");
+
+  /* Sanity checks */
+
+  DEBUGASSERT(filep->f_priv != NULL && filep->f_inode != NULL);
+
+  /* Recover the open file state from the struct file instance */
+
+  ofile = (FAR struct nxffs_ofile_s *)filep->f_priv;
+
+  /* Recover the volume state from the open file */
+
+  volume = (FAR struct nxffs_volume_s *)filep->f_inode->i_private;
+  DEBUGASSERT(volume != NULL);
+
+  /* Get exclusive access to the volume.  Note that the volume exclsem
+   * protects the open file list.
+   */
+
+  ret = sem_wait(&volume->exclsem);
+  if (ret != OK)
+    {
+      ret = -errno;
+      fdbg("sem_wait failed: %d\n", ret);
+      goto errout;
+    }
+
+  /* Decrement the reference count on the open file */
+
+  if (ofile->crefs == 1)
+    {
+      /* Decrementing the reference count would take it zero.  Time to
+       * delete the open file state.
+       */
+
+      nxffs_freeofile(ofile);
+    }
+  else
+    {
+      /* Just decrement the reference count */
+
+      ofile->crefs--;
+    }
+
+  filep->f_priv = NULL;
+  ret = OK;
+
+  sem_post(&volume->exclsem);
+errout:
+  return ret;
+}
diff --git a/nuttx/fs/nxffs/nxffs_stat.c b/nuttx/fs/nxffs/nxffs_stat.c
new file mode 100644
index 000000000..57649dacc
--- /dev/null
+++ b/nuttx/fs/nxffs/nxffs_stat.c
@@ -0,0 +1,186 @@
+/****************************************************************************
+ * fs/nxffs/nxffs_stat.c
+ *
+ *   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.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/stat.h>
+#include <sys/statfs.h>
+
+#include <string.h>
+#include <fcntl.h>
+#include <assert.h>
+#include <debug.h>
+
+#include <nuttx/fs.h>
+#include <nuttx/mtd.h>
+
+#include "nxffs.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: nxffs_statfs
+ *
+ * Description: Return filesystem statistics
+ *
+ ****************************************************************************/
+
+int nxffs_statfs(FAR struct inode *mountpt, FAR struct statfs *buf)
+{
+  FAR struct nxffs_volume_s *volume;
+  int ret;
+
+  fvdbg("Entry\n");
+
+  /* Sanity checks */
+
+  DEBUGASSERT(mountpt && mountpt->i_private);
+
+  /* Get the mountpoint private data from the NuttX inode structure */
+
+  volume = mountpt->i_private;
+  ret = sem_wait(&volume->exclsem);
+  if (ret != OK)
+    {
+      goto errout;
+    }
+
+  /* Fill in the statfs info */
+#warning "Need f_bfree, f_bavail, f_files, f_ffree calculation"
+
+  memset(buf, 0, sizeof(struct statfs));
+  buf->f_type    = NXFFS_MAGIC;
+  buf->f_bsize   = volume->geo.blocksize;
+  buf->f_blocks  = volume->geo.neraseblocks * volume->blkper;
+  buf->f_namelen = volume->geo.blocksize - SIZEOF_NXFFS_BLOCK_HDR - SIZEOF_NXFFS_INODE_HDR;
+  ret            = OK;
+
+  sem_post(&volume->exclsem);
+errout:
+  return ret;
+}
+
+/****************************************************************************
+ * Name: nxffs_stat
+ *
+ * Description: Return information about a file or directory
+ *
+ ****************************************************************************/
+
+int nxffs_stat(FAR struct inode *mountpt, FAR const char *relpath,
+               FAR struct stat *buf)
+{
+  FAR struct nxffs_volume_s *volume;
+  struct nxffs_entry_s entry;
+  int ret;
+
+  fvdbg("Entry\n");
+
+  /* Sanity checks */
+
+  DEBUGASSERT(mountpt && mountpt->i_private && buf);
+
+  /* Get the mountpoint private data from the NuttX inode structure */
+
+  volume = mountpt->i_private;
+  ret = sem_wait(&volume->exclsem);
+  if (ret != OK)
+    {
+      goto errout;
+    }
+
+  /* Initialize the return stat instance */
+
+  memset(buf, 0, sizeof(struct stat));
+  buf->st_blksize = volume->geo.blocksize;
+  buf->st_blocks  = entry.datlen / (volume->geo.blocksize - SIZEOF_NXFFS_BLOCK_HDR);
+
+  /* The requested directory must be the volume-relative "root" directory */
+
+  if (relpath && relpath[0] != '\0')
+    {
+      /* Not the top directory.. find the NXFFS inode with this name */
+
+      ret = nxffs_findinode(volume, relpath, &entry);
+      if (ret < 0)
+        {
+          fdbg("Inode '%s' not found: %d\n", -ret);
+          goto errout_with_semaphore;
+        }
+
+      buf->st_mode    = S_IFREG|S_IXOTH|S_IXGRP|S_IXUSR;
+      buf->st_size    = entry.datlen;
+      buf->st_atime   = entry.utc;
+      buf->st_mtime   = entry.utc;
+      buf->st_ctime   = entry.utc;
+    }
+  else
+    {
+      /* It's a read/execute-only directory name */
+
+      buf->st_mode   = S_IFDIR|S_IROTH|S_IRGRP|S_IRUSR|S_IXOTH|S_IXGRP|S_IXUSR;
+    }
+
+  ret = OK;
+
+errout_with_semaphore:
+  sem_post(&volume->exclsem);
+errout:
+  return ret;
+}
diff --git a/nuttx/fs/nxffs/nxffs_unlink.c b/nuttx/fs/nxffs/nxffs_unlink.c
new file mode 100644
index 000000000..46037a1b0
--- /dev/null
+++ b/nuttx/fs/nxffs/nxffs_unlink.c
@@ -0,0 +1,184 @@
+/****************************************************************************
+ * fs/nxffs/nxffs_unlink.c
+ *
+ *   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.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <string.h>
+#include <errno.h>
+#include <assert.h>
+#include <debug.h>
+
+#include <nuttx/fs.h>
+#include <nuttx/mtd.h>
+
+#include "nxffs.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Types
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: nxffs_rminode
+ *
+ * Description:
+ *   Remove an inode from FLASH.  This is the internal implementation of
+ *   the file system unlinke operation.
+ *
+ * Input Parameters:
+ *   volume - Describes the NXFFS volume.
+ *   name - the name of the inode to be deleted.
+ *
+ * Returned Value:
+ *   Zero is returned if the inode is successfully deleted.  Otherwise, a
+ *   negated errno value is returned indicating the nature of the failure.
+ *
+ ****************************************************************************/
+
+int nxffs_rminode(FAR struct nxffs_volume_s *volume, FAR const char *name)
+{
+  FAR struct nxffs_ofile_s *ofile;
+  FAR struct nxffs_inode_s *inode;
+  struct nxffs_entry_s entry;
+  int ret;
+
+  /* Check if the file is open */
+
+  ofile = nxffs_findofile(name);
+  if (ofile)
+    {
+      /* We can't remove the inode if it is open */
+
+      fdbg("Inode is open\n");
+      return -EBUSY;
+    }
+
+  /* Find the NXFFS inode */
+
+  ret = nxffs_findinode(volume, name, &entry);
+  if (ret < 0)
+    {
+      fdbg("Inode '%s' not found\n");
+      return ret;
+    }
+
+  /* Set the position to the FLASH offset of the file header (nxffs_findinode
+   * should have left the block in the cache).
+   */
+
+  nxffs_ioseek(volume, entry.hoffset);
+
+  /* Make sure the the block is in the cache */
+
+  ret = nxffs_rdcache(volume, volume->ioblock, 1);
+  if (ret < 0)
+    {
+      fdbg("Failed to read data into cache: %d\n", ret);
+      return ret;
+    }
+
+  /* Change the file status... it is no longer valid */
+
+  inode = (FAR struct nxffs_inode_s *)&volume->cache[volume->iooffset];
+  inode->state = INODE_STATE_DELETED;
+
+  /* Then write the cached block back to FLASH */
+
+  ret = nxffs_wrcache(volume, volume->ioblock, 1);
+  if (ret < 0)
+    {
+      fdbg("Failed to read data into cache: %d\n", ret);
+      return ret;
+    }
+
+  return OK;
+}
+
+/****************************************************************************
+ * Name: nxffs_unlink
+ *
+ * Description: Remove a file
+ *
+ ****************************************************************************/
+
+int nxffs_unlink(FAR struct inode *mountpt, FAR const char *relpath)
+{
+  FAR struct nxffs_volume_s *volume;
+  int ret;
+
+  fvdbg("Entry\n");
+
+  /* Sanity checks */
+
+  DEBUGASSERT(mountpt && mountpt->i_private);
+
+  /* Get the mountpoint private data from the NuttX inode structure */
+
+  volume = mountpt->i_private;
+  ret = sem_wait(&volume->exclsem);
+  if (ret != OK)
+    {
+      goto errout;
+    }
+
+  /* Then remove the NXFFS inode */
+
+  ret = nxffs_rminode(volume, relpath);
+  
+  sem_post(&volume->exclsem);
+errout:
+  return ret;
+}
diff --git a/nuttx/fs/nxffs/nxffs_util.c b/nuttx/fs/nxffs/nxffs_util.c
index 9eea32243..5217fe09e 100644
--- a/nuttx/fs/nxffs/nxffs_util.c
+++ b/nuttx/fs/nxffs/nxffs_util.c
@@ -42,11 +42,6 @@
 #include <nuttx/config.h>
 
 #include <string.h>
-#include <errno.h>
-#include <assert.h>
-#include <debug.h>
-
-#include <nuttx/mtd.h>
 
 #include "nxffs.h"
 
diff --git a/nuttx/include/sys/statfs.h b/nuttx/include/sys/statfs.h
index 9c7ee26e5..7f80902d6 100644
--- a/nuttx/include/sys/statfs.h
+++ b/nuttx/include/sys/statfs.h
@@ -1,7 +1,7 @@
 /****************************************************************************
  * include/sys/statfs.h
  *
- *   Copyright (C) 2007-2009 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2009, 2011 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -52,27 +52,27 @@
 /* struct statfs file system types. */
 
 #define ADFS_SUPER_MAGIC      0xadf5
-#define AFFS_SUPER_MAGIC      0xADFF
+#define AFFS_SUPER_MAGIC      0xadff
 #define BEFS_SUPER_MAGIC      0x42465331
-#define BFS_MAGIC             0x1BADFACE
-#define CIFS_MAGIC_NUMBER     0xFF534D42
+#define BFS_MAGIC             0x1badface
+#define CIFS_MAGIC_NUMBER     0xff534d42
 #define CODA_SUPER_MAGIC      0x73757245
-#define COH_SUPER_MAGIC       0x012FF7B7
+#define COH_SUPER_MAGIC       0x012ff7b7
 #define CRAMFS_MAGIC          0x28cd3d45
 #define DEVFS_SUPER_MAGIC     0x1373
-#define EFS_SUPER_MAGIC       0x00414A53
-#define EXT_SUPER_MAGIC       0x137D
-#define EXT2_OLD_SUPER_MAGIC  0xEF51
-#define EXT2_SUPER_MAGIC      0xEF53
-#define EXT3_SUPER_MAGIC      0xEF53
+#define EFS_SUPER_MAGIC       0x00414a53
+#define EXT_SUPER_MAGIC       0x137d
+#define EXT2_OLD_SUPER_MAGIC  0xef51
+#define EXT2_SUPER_MAGIC      0xef53
+#define EXT3_SUPER_MAGIC      0xef53
 #define HFS_SUPER_MAGIC       0x4244
-#define HPFS_SUPER_MAGIC      0xF995E849
+#define HPFS_SUPER_MAGIC      0xf995e849
 #define HUGETLBFS_MAGIC       0x958458f6
 #define ISOFS_SUPER_MAGIC     0x9660
 #define JFFS2_SUPER_MAGIC     0x72b6
 #define JFS_SUPER_MAGIC       0x3153464a
-#define MINIX_SUPER_MAGIC     0x137F /* orig. minix */
-#define MINIX_SUPER_MAGIC2    0x138F /* 30 char minix */
+#define MINIX_SUPER_MAGIC     0x137f /* orig. minix */
+#define MINIX_SUPER_MAGIC2    0x138f /* 30 char minix */
 #define MINIX2_SUPER_MAGIC    0x2468 /* minix V2 */
 #define MINIX2_SUPER_MAGIC2   0x2478 /* minix V2, 30 char names */
 #define MSDOS_SUPER_MAGIC     0x4d44
@@ -85,17 +85,21 @@
 #define REISERFS_SUPER_MAGIC  0x52654973
 #define ROMFS_MAGIC           0x7275
 #define SMB_SUPER_MAGIC       0x517B
-#define SYSV2_SUPER_MAGIC     0x012FF7B6
+#define SYSV2_SUPER_MAGIC     0x012ff7b6
 #define SYSV4_SUPER_MAGIC     0x012FF7B5
 #define TMPFS_MAGIC           0x01021994
 #define UDF_SUPER_MAGIC       0x15013346
 #define UFS_MAGIC             0x00011954
 #define USBDEVICE_SUPER_MAGIC 0x9fa2
-#define VXFS_SUPER_MAGIC      0xa501FCF5
-#define XENIX_SUPER_MAGIC     0x012FF7B4
+#define VXFS_SUPER_MAGIC      0xa501fcf5
+#define XENIX_SUPER_MAGIC     0x012ff7b4
 #define XFS_SUPER_MAGIC       0x58465342
-#define _XIAFS_SUPER_MAGIC    0x012FD16D
+#define _XIAFS_SUPER_MAGIC    0x012fd16d
+
+/* NuttX specific file-systems */
+
 #define BINFS_MAGIC           0x4242
+#define NXFFS_MAGIC           0x4747
 
 /****************************************************************************
  * Type Definitions