fs/coda/pioctl.c

   1 /*
   2  * Pioctl operations for Coda.
   3  * Original version: (C) 1996 Peter Braam
   4  * Rewritten for Linux 2.1: (C) 1997 Carnegie Mellon University
   5  *
   6  * Carnegie Mellon encourages users of this code to contribute improvements
   7  * to the Coda project. Contact Peter Braam <coda@cs.cmu.edu>.
   8  */
   9
  10 #include <linux/types.h>
  11 #include <linux/kernel.h>
  12 #include <linux/sched.h>
  13 #include <linux/fs.h>
  14 #include <linux/stat.h>
  15 #include <linux/errno.h>
  16 #include <linux/locks.h>
  17 #include <asm/segment.h>
  18 #include <linux/string.h>
  19 #include <asm/uaccess.h>
  20
  21 #include <linux/coda.h>
  22 #include <linux/coda_linux.h>
  23 #include <linux/coda_fs_i.h>
  24 #include <linux/coda_cache.h>
  25 #include <linux/coda_psdev.h>
  26
  27 /* pioctl ops */
  28 static int coda_ioctl_permission(struct inode *inode, int mask);
  29 static int coda_ioctl_open(struct inode *i, struct file *f);
  30 static int coda_ioctl_release(struct inode *i, struct file *f);
  31 static int coda_pioctl(struct inode * inode, struct file * filp,
  32                        unsigned int cmd, unsigned long arg);
  33
  34 /* exported from this file */
  35 struct inode_operations coda_ioctl_inode_operations =
  36 {
  37         &coda_ioctl_operations,
  38         NULL,                   /* create */
  39         NULL,                   /* lookup */
  40         NULL,                   /* link */
  41         NULL,                   /* unlink */
  42         NULL,                   /* symlink */
  43         NULL,                   /* mkdir */
  44         NULL,                   /* rmdir */
  45         NULL,                   /* mknod */
  46         NULL,                   /* rename */
  47         NULL,                   /* readlink */
  48         NULL,                   /* follow_link */
  49         NULL,                   /* get_block */
  50         NULL,                   /* readpage */
  51         NULL,                   /* writepage */
  52         NULL,                   /* flushpage */
  53         NULL,                   /* truncate */
  54         coda_ioctl_permission,  /* permission */
  55         NULL,                   /* smap */
  56         NULL                    /* revalidate */
  57 };
  58
  59 struct file_operations coda_ioctl_operations = {
  60         NULL,                   /* lseek - default should work for coda */
  61         NULL,                   /* read */
  62         NULL,                   /* write */
  63         NULL,                   /* readdir */
  64         NULL,                   /* select - default */
  65         coda_pioctl,            /* ioctl */
  66         NULL,                   /* mmap */
  67         coda_ioctl_open,        /* open */
  68         NULL,
  69         coda_ioctl_release,     /* release */
  70         NULL,                   /* fsync */
  71 };
  72
  73 /* the coda pioctl inode ops */
  74 static int coda_ioctl_permission(struct inode *inode, int mask)
  75 {
  76         ENTRY;
  77
  78         return 0;
  79 }
  80
  81 /* The pioctl file ops*/
  82 int coda_ioctl_open(struct inode *i, struct file *f)
  83 {
  84
  85         ENTRY;
  86
  87         CDEBUG(D_PIOCTL, "File inode number: %ld\n",
  88                f->f_dentry->d_inode->i_ino);
  89
  90         EXIT;
  91         return 0;
  92 }
  93
  94 int coda_ioctl_release(struct inode *i, struct file *f)
  95 {
  96         return 0;
  97 }
  98
  99
 100 static int coda_pioctl(struct inode * inode, struct file * filp,
 101                        unsigned int cmd, unsigned long user_data)
 102 {
 103         struct dentry *target_de;
 104         int error;
 105         struct PioctlData data;
 106         struct inode *target_inode = NULL;
 107         struct coda_inode_info *cnp;
 108
 109         ENTRY;
 110         /* get the Pioctl data arguments from user space */
 111         if (copy_from_user(&data, (int *)user_data, sizeof(data))) {
 112             return -EINVAL;
 113         }
 114
 115         /*
 116          * Look up the pathname. Note that the pathname is in
 117          * user memory, and namei takes care of this
 118          */
 119         CDEBUG(D_PIOCTL, "namei, data.follow = %d\n",
 120                data.follow);
 121         if ( data.follow ) {
 122                 target_de = namei(data.path);
 123         } else {
 124                 target_de = lnamei(data.path);
 125         }
 126
 127         if ( IS_ERR(target_de) ) {
 128                 CDEBUG(D_PIOCTL, "error: lookup fails.\n");
 129                 return PTR_ERR(target_de);
 130         } else {
 131                 target_inode = target_de->d_inode;
 132         }
 133
 134         CDEBUG(D_PIOCTL, "target ino: 0x%ld, dev: 0x%d\n",
 135                target_inode->i_ino, target_inode->i_dev);
 136
 137         /* return if it is not a Coda inode */
 138         if ( target_inode->i_sb != inode->i_sb ) {
 139                 if ( target_de )
 140                         dput(target_de);
 141                 return  -EINVAL;
 142         }
 143
 144         /* now proceed to make the upcall */
 145         cnp = ITOC(target_inode);
 146
 147         error = venus_pioctl(inode->i_sb, &(cnp->c_fid), cmd, &data);
 148
 149         CDEBUG(D_PIOCTL, "ioctl on inode %ld\n", target_inode->i_ino);
 150         CDEBUG(D_DOWNCALL, "dput on ino: %ld, icount %d, dcount %d\n", target_inode->i_ino,
 151                target_inode->i_count, target_de->d_count);
 152         if ( target_de )
 153                 dput(target_de);
 154         return error;
 155 }
 156