libblock: Change bdbuf API

The functions
 o rtems_bdbuf_get(),
 o rtems_bdbuf_read(),
 o rtems_bdbuf_syncdev(), and
 o rtems_bdbuf_purge_dev(),
use now the disk device instead of the device identifier.  This makes
bdbuf independent of rtems_disk_obtain() and rtems_disk_release().  It
is the responsiblity of the file system to obtain the disk device.  This
also reduces the overhead to get a buffer.

The key for the AVL tree uses now the disk device instead of the device
identifier.  The pointer is interpreted as an unsigned integer.  This
reduces the memory overhead and makes the comparison operation a bit
faster.

Removed function rtems_bdbuf_purge_major().  This function was too
destructive and could have unpredictable side effects.

1 files changed, 19 insertions, 16 deletions

diff --git a/cpukit/libfs/src/rfs/rtems-rfs-buffer.c b/cpukit/libfs/src/rfs/rtems-rfs-buffer.c
index ea5cbb3fb3..60f9deae32 100644
--- a/cpukit/libfs/src/rfs/rtems-rfs-buffer.c
+++ b/cpukit/libfs/src/rfs/rtems-rfs-buffer.c
@@ -20,8 +20,10 @@
 #include "config.h"
 #endif
 
+#include <sys/stat.h>
 #include <inttypes.h>
 #include <errno.h>
+#include <fcntl.h>
 
 #include <rtems/rfs/rtems-rfs-buffer.h>
 #include <rtems/rfs/rtems-rfs-file-system.h>
@@ -285,16 +287,27 @@ int
 rtems_rfs_buffer_open (const char* name, rtems_rfs_file_system* fs)
 {
   struct stat st;
+#if RTEMS_RFS_USE_LIBBLOCK
+  int rv;
+#endif
 
   if (rtems_rfs_trace (RTEMS_RFS_TRACE_BUFFER_SYNC))
     printf ("rtems-rfs: buffer-open: opening: %s\n", name);
 
-  if (stat (name, &st) < 0)
+  fs->device = open (name, O_RDWR);
+  if (fs->device < 0)
+  {
+    if (rtems_rfs_trace (RTEMS_RFS_TRACE_BUFFER_OPEN))
+      printf ("rtems-rfs: buffer-open: cannot open file\n");
+    return ENXIO;
+  }
+
+  if (fstat (fs->device, &st) < 0)
   {
     if (rtems_rfs_trace (RTEMS_RFS_TRACE_BUFFER_OPEN))
       printf ("rtems-rfs: buffer-open: stat '%s' failed: %s\n",
               name, strerror (errno));
-    return ENOENT;
+    return ENXIO;
   }
 
 #if RTEMS_RFS_USE_LIBBLOCK
@@ -305,26 +318,20 @@ rtems_rfs_buffer_open (const char* name, rtems_rfs_file_system* fs)
   {
     if (rtems_rfs_trace (RTEMS_RFS_TRACE_BUFFER_OPEN))
       printf ("rtems-rfs: buffer-open: '%s' is not a block device\n", name);
-    return EIO;
+    return ENXIO;
   }
 
   /*
    * Check that device is registred as a block device and lock it.
    */
-  fs->disk = rtems_disk_obtain (st.st_rdev);
-  if (!fs->disk)
+  rv = rtems_disk_fd_get_disk_device (fs->device, &fs->disk);
+  if (rv != 0)
   {
     if (rtems_rfs_trace (RTEMS_RFS_TRACE_BUFFER_OPEN))
       printf ("rtems-rfs: buffer-open: cannot obtain the disk\n");
-    return EIO;
+    return ENXIO;
   }
 #else
-  fs->device = open (name, O_RDWR);
-  if (fs->device < 0)
-  {
-    if (rtems_rfs_trace (RTEMS_RFS_TRACE_BUFFER_OPEN))
-      printf ("rtems-rfs: buffer-open: cannot open file\n");
-  }
   fs->media_size = st.st_size;
   strcat (fs->name, name);
 #endif
@@ -355,9 +362,6 @@ rtems_rfs_buffer_close (rtems_rfs_file_system* fs)
     printf ("rtems-rfs: buffer-close: set media block size failed: %d: %s\n",
             rc, strerror (rc));
 
-#if RTEMS_RFS_USE_LIBBLOCK
-  rtems_disk_release (fs->disk);
-#else
   if (close (fs->device) < 0)
   {
     rc = errno;
@@ -365,7 +369,6 @@ rtems_rfs_buffer_close (rtems_rfs_file_system* fs)
       printf ("rtems-rfs: buffer-close: file close failed: %d: %s\n",
               rc, strerror (rc));
   }
-#endif
 
   return rc;
 }