servers/iso9660fs/mount.c

   1 #include "inc.h"
   2 #include <string.h>
   3 #include <minix/com.h>
   4 #include <minix/vfsif.h>
   5 #include <minix/ds.h>
   6 #include "const.h"
   7 #include "glo.h"
   8
   9
  10 /*===========================================================================*
  11  *                              fs_readsuper                                 *
  12  *===========================================================================*/
  13 PUBLIC int fs_readsuper() {
  14
  15   cp_grant_id_t label_gid;
  16   size_t label_len;
  17   int r = OK;
  18   unsigned long tasknr;
  19   endpoint_t driver_e;
  20   int readonly;
  21
  22   fs_dev    = fs_m_in.REQ_DEV;
  23   label_gid = fs_m_in.REQ_GRANT;
  24   label_len = fs_m_in.REQ_PATH_LEN;
  25   readonly  = 1;                        /* Always mount devices read only. */
  26
  27   if (label_len > sizeof(fs_dev_label))
  28         return(EINVAL);
  29
  30   r = sys_safecopyfrom(fs_m_in.m_source, label_gid, 0, (vir_bytes)fs_dev_label,
  31                        label_len, D);
  32   if (r != OK) {
  33         printf("ISOFS %s:%d safecopyfrom failed: %d\n", __FILE__, __LINE__, r);
  34         return(EINVAL);
  35   }
  36
  37   r = ds_retrieve_label_num(fs_dev_label, &tasknr);
  38   if (r != OK) {
  39         printf("ISOFS %s:%d ds_retrieve_label_num failed for '%s': %d\n",
  40                 __FILE__, __LINE__, fs_dev_label, r);
  41         return(EINVAL);
  42   }
  43
  44   driver_e = tasknr;
  45
  46   /* Map the driver endpoint for this major */
  47   driver_endpoints[(fs_dev >> MAJOR) & BYTE].driver_e =  driver_e;
  48
  49   /* Open the device the file system lives on */
  50   if (dev_open(driver_e, fs_dev, driver_e,
  51         readonly ? R_BIT : (R_BIT|W_BIT)) != OK) {
  52         return(EINVAL);
  53   }
  54
  55   /* Read the superblock */
  56   r = read_vds(&v_pri, fs_dev);
  57   if (r != OK)
  58         return(r);
  59
  60   /* Return some root inode properties */
  61   fs_m_out.RES_INODE_NR = ID_DIR_RECORD(v_pri.dir_rec_root);
  62   fs_m_out.RES_MODE = v_pri.dir_rec_root->d_mode;
  63   fs_m_out.RES_FILE_SIZE_LO = v_pri.dir_rec_root->d_file_size;
  64   fs_m_out.RES_UID = SYS_UID; /* Always root */
  65   fs_m_out.RES_GID = SYS_GID; /* operator */
  66
  67   return(r);
  68 }
  69
  70
  71 /*===========================================================================*
  72  *                              fs_mountpoint                                *
  73  *===========================================================================*/
  74 PUBLIC int fs_mountpoint() {
  75 /* This function looks up the mount point, it checks the condition whether
  76  * the partition can be mounted on the inode or not.
  77  */
  78
  79   register struct dir_record *rip;
  80   int r = OK;
  81   mode_t bits;
  82
  83   /* Temporarily open the file. */
  84   if ((rip = get_dir_record(fs_m_in.REQ_INODE_NR)) == NULL)
  85         return(EINVAL);
  86
  87   if (rip->d_mountpoint)
  88         r = EBUSY;
  89
  90   /* If the inode is not a dir returns error */
  91   if ((rip->d_mode & I_TYPE) != I_DIRECTORY)
  92         r = ENOTDIR;
  93
  94   release_dir_record(rip);
  95
  96   if (r == OK)
  97         rip->d_mountpoint = TRUE;
  98
  99   return(r);
 100 }
 101
 102
 103 /*===========================================================================*
 104  *                              fs_unmount                                   *
 105  *===========================================================================*/
 106 PUBLIC int fs_unmount(void) {
 107   release_v_pri(&v_pri);        /* Release the super block */
 108   dev_close(driver_endpoints[(fs_dev >> MAJOR) & BYTE].driver_e, fs_dev);
 109   return(OK);
 110 }
 111