Add structures to manage block drivers

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@207 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 103 insertions, 43 deletions

diff --git a/nuttx/include/nuttx/fs.h b/nuttx/include/nuttx/fs.h
index 7e0eb8980..af9fd924b 100644
--- a/nuttx/include/nuttx/fs.h
+++ b/nuttx/include/nuttx/fs.h
@@ -1,5 +1,5 @@
-/************************************************************
- * fs.h
+/****************************************************************************
+ * nutts/fs.h
  *
  *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
@@ -31,63 +31,108 @@
  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  *
- ************************************************************/
+ ****************************************************************************/
 
-#ifndef __FS_H
-#define __FS_H
+#ifndef __NUTTX_FS_H
+#define __NUTTX_FS_H
 
-/************************************************************
+/****************************************************************************
  * Included Files
- ************************************************************/
+ ****************************************************************************/
 
 #include <sys/types.h>
 #include <semaphore.h>
 #include <nuttx/compiler.h>
 
-/************************************************************
+/****************************************************************************
  * Definitions
- ************************************************************/
+ ****************************************************************************/
 
-/************************************************************
+/****************************************************************************
  * Type Definitions
- ************************************************************/
+ ****************************************************************************/
 
-/* This structure is provided by filesystems when they are
- * registered with the system.  It is used to call back to
- * perform fs/device specific operations.
+/* This structure is provided by devices when they are registered with the
+ * system.  It is used to call back to perform device specific operations.
  */
 
 struct file;
 struct file_operations
 {
-  int     (*open)(FAR struct file *);
-  int     (*close)(FAR struct file *);
-  ssize_t (*read)(FAR struct file *, char *, size_t);
-  ssize_t (*write)(FAR struct file *, const char *, size_t);
+  int     (*open)(FAR struct file *filp);
+  int     (*close)(FAR struct file *filp);
+  ssize_t (*read)(FAR struct file *filp, char *buffer, size_t buflen);
+  ssize_t (*write)(FAR struct file *filp, const char *buffer, size_t buflen);
+  off_t   (*seek)(FAR struct file *filp, off_t offset, int whence);
+  int     (*ioctl)(FAR struct file *filp, int cmd, unsigned long arg);
+};
+
+/* This structure provides information about the state of a block driver */
+
+struct geometry
+{
+  boolean geo_available;  /* False if the device is not available */
+  size_t  geo_nsectors;   /* Number of sectors on the device */
+  size_t  geo_sectorsize; /* Size of one sector */
+};
+
+/* This structure is provided by block devices when they register with the
+ * system.  It is used by file systems to perform filesystem transfers.
+ */
+
+struct block_operations
+{
+  int     (*open)(FAR struct file *filp);
+  int     (*close)(FAR struct file *filp);
+  ssize_t (*read)(FAR struct file *filp, char *buffer,
+                  size_t start_sector, size_t nsectors);
+  ssize_t (*write)(FAR struct file *filp, const char *buffer,
+                   size_t start_sector, size_t nsectors);
+  size_t  (*geometry)(FAR struct file *filp, struct geometry *geometry);
   int     (*ioctl)(FAR struct file *, int, unsigned long);
 };
 
+/* This structure is provided by a filesystem to describe a mount point.
+ * Note that this structure differs from file_operations ONLY in the form of
+ * the open method.  Once the file is opened, it can be accessed either as a
+ * struct file_operations or struct mountpt_operations
+ */
+
+struct mountpt_operations
+{
+  int     (*open)(FAR struct file *filp, const char *rel_path);
+  int     (*close)(FAR struct file *filp);
+  ssize_t (*read)(FAR struct file *filp, char *buffer, size_t buflen);
+  ssize_t (*write)(FAR struct file *filp, const char *buffer, size_t buflen);
+  off_t   (*seek)(FAR struct file *filp, off_t offset, int whence);
+  int     (*ioctl)(FAR struct file *filp, int cmd, unsigned long arg);
+};
+
 /* This structure represents one inode in the Nuttx psuedo-file system */
 
 struct inode
 {
-  FAR struct inode           *i_peer;    /* Pointer to inode at same level */
-  FAR struct inode           *i_child;   /* Pointer to inode at lower level */
-  struct file_operations     *i_ops;     /* Driver file operations for inode */
-  sint16                      i_crefs;   /* References to inode */
-  uint16                      i_flags;   /* flags for inode */
+  FAR struct inode            *i_peer;       /* Pointer to same level inode */
+  FAR struct inode            *i_child;      /* Pointer to lower level inode */
+  sint16                       i_crefs;      /* References to inode */
+  uint16                       i_flags;      /* flags for inode */
+  union
+  {
+    const struct file_operations    *i_ops;  /* Driver operations for inode */
+    const struct block_operations   *i_bops; /* Block driver operations */
+    const struct mountpt_operations *i_mops; /* Operations on a mountpoint */
+  } u;
 #ifdef CONFIG_FILE_MODE
-  mode_t                      i_mode;    /* Access mode flags */
+  mode_t                       i_mode;       /* Access mode flags */
 #endif
-  FAR void                   *i_private; /* Driver private data */
-  char                        i_name[1]; /* Name of inode (variable length) */
+  FAR void                    *i_private;    /* Driver private data */
+  char                         i_name[1];    /* Name of inode (variable) */
 };
 #define FSNODE_SIZE(n) (sizeof(struct inode) + (n))
 
-/* This is the underlying representation of a ropen file.
- * A file descriptor is an index into an array of such types.
- * The type associates the file descriptor to the file state
- * and to a set of inode operations.
+/* This is the underlying representation of an open file.  A file
+ * descriptor is an index into an array of such types. The type associates
+ * the file descriptor to the file state and to a set of inode operations.
  */
 
 struct file
@@ -95,6 +140,7 @@ struct file
   int               f_oflags; /* Open mode flags */
   off_t             f_pos;    /* File position */
   FAR struct inode *f_inode;  /* Driver interface */
+  void             *f_priv;   /* Per file driver private data */
 };
 
 /* This defines a list of files indexed by the file descriptor */
@@ -142,9 +188,9 @@ struct streamlist
 };
 #endif /* CONFIG_NFILE_STREAMS */
 
-/************************************************************
+/****************************************************************************
  * Global Function Prototypes
- ************************************************************/
+ ****************************************************************************/
 
 #undef EXTERN
 #if defined(__cplusplus)
@@ -154,23 +200,37 @@ extern "C" {
 #define EXTERN extern
 #endif
 
-/* fs_inode.c ***********************************************/
+/* fs_inode.c ***************************************************************/
 
 /* These interfaces are used by drivers to register their
  * inodes in the inode tree.
  */
 
 EXTERN void   weak_function fs_initialize(void);
-EXTERN STATUS register_inode(const char *path,
-                             struct file_operations *fops,
-                             mode_t mode, void *private);
-EXTERN STATUS unregister_inode(const char *path);
 
-/* fs_open.c ************************************************/
+/* fs_registerdriver.c ******************************************************/
+
+EXTERN STATUS register_driver(const char *path,
+                              const struct file_operations *fops,
+                              mode_t mode, void *private);
+
+/* fs_registerdriver.c ******************************************************/
+
+EXTERN STATUS register_blockdriver(const char *path,
+                                   const struct block_operations *bops,
+                                   mode_t mode, void *private);
+
+/* fs_inoderemove.c *********************************************************/
+
+EXTERN STATUS inode_remove(const char *path);
+#define unregister_driver(p) inode_remove(p)
+#define unregister_blockdriver(p) inode_remove(p)
+
+/* fs_open.c ****************************************************************/
 
 EXTERN int   inode_checkflags(FAR struct inode *inode, int oflags);
 
-/* fs_files.c ***********************************************/
+/* fs_files.c ***************************************************************/
 
 #if CONFIG_NFILE_DESCRIPTORS >0
 EXTERN FAR struct filelist *files_alloclist(void);
@@ -179,7 +239,7 @@ EXTERN int files_releaselist(FAR struct filelist *list);
 EXTERN int files_dup(FAR struct file *filep1, FAR struct file *filep2);
 #endif
 
-/* lib_fopen.c **********************************************/
+/* lib_fopen.c **************************************************************/
 
 /* Used by the OS to clone stdin, stdout, stderr */
 
@@ -190,13 +250,13 @@ EXTERN FAR struct file_struct *lib_fdopen(int fd,
                                           FAR struct streamlist *slist);
 #endif
 
-/* lib_fflush.c *********************************************/
+/* lib_fflush.c *************************************************************/
 
 #if CONFIG_NFILE_STREAMS > 0
 EXTERN void lib_flushall(FAR struct streamlist *list);
 #endif
 
-/* drivers **************************************************/
+/* drivers ******************************************************************/
 
 /* Call in of these to register the corresponding default 
  * default drivers in the drivers/ subdirectory
@@ -210,4 +270,4 @@ EXTERN void devnull_register(void);
 }
 #endif
 
-#endif /* __FS_H */
+#endif /* __NUTTX_FS_H */