minix/lib/libsffs/misc.c

   1 /* This file contains miscellaneous file system call handlers.
   2  *
   3  * The entry points into this file are:
   4  *   do_statvfs         perform the STATVFS file system call
   5  *
   6  * Created:
   7  *   April 2009 (D.C. van Moolenbroek)
   8  */
   9
  10 #include "inc.h"
  11
  12 #include <sys/statvfs.h>
  13
  14 /*===========================================================================*
  15  *                              do_statvfs                                   *
  16  *===========================================================================*/
  17 int do_statvfs(struct statvfs *st)
  18 {
  19 /* Retrieve file system statistics.
  20  */
  21   struct inode *ino;
  22   char path[PATH_MAX];
  23   u64_t bfree, btotal;
  24   int r;
  25
  26   /* Unfortunately, we cannot be any more specific than this, because we are
  27    * not given an inode number. Statistics of individual shared folders can
  28    * only be obtained by making sure that the root of the file system is an
  29    * actual share, and not a list of available shares.
  30    */
  31   if ((ino = find_inode(ROOT_INODE_NR)) == NULL)
  32         return EINVAL;
  33
  34   if ((r = verify_inode(ino, path, NULL)) != OK)
  35         return r;
  36
  37   if ((r = sffs_table->t_queryvol(path, &bfree, &btotal)) != OK)
  38         return r;
  39
  40   /* Returning zero for unknown values seems to be the convention. However, we
  41    * do have to use a nonzero block size, even though it is entirely arbitrary.
  42    */
  43   st->f_flag = ST_NOTRUNC;
  44   st->f_bsize = BLOCK_SIZE;
  45   st->f_frsize = BLOCK_SIZE;
  46   st->f_iosize = BLOCK_SIZE;
  47   st->f_blocks = (fsblkcnt_t)(btotal / BLOCK_SIZE);
  48   st->f_bfree = (fsblkcnt_t)(bfree / BLOCK_SIZE);
  49   st->f_bavail = st->f_bfree;
  50   st->f_namemax = NAME_MAX;
  51
  52   return OK;
  53 }