fs/cifs/ioctl.c

   1 /*
   2  *   fs/cifs/ioctl.c
   3  *
   4  *   vfs operations that deal with io control
   5  *
   6  *   Copyright (C) International Business Machines  Corp., 2005,2013
   7  *   Author(s): Steve French (sfrench@us.ibm.com)
   8  *
   9  *   This library is free software; you can redistribute it and/or modify
  10  *   it under the terms of the GNU Lesser General Public License as published
  11  *   by the Free Software Foundation; either version 2.1 of the License, or
  12  *   (at your option) any later version.
  13  *
  14  *   This library is distributed in the hope that it will be useful,
  15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  17  *   the GNU Lesser General Public License for more details.
  18  *
  19  *   You should have received a copy of the GNU Lesser General Public License
  20  *   along with this library; if not, write to the Free Software
  21  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  22  */
  23
  24 #include <linux/fs.h>
  25 #include <linux/file.h>
  26 #include <linux/mount.h>
  27 #include <linux/mm.h>
  28 #include <linux/pagemap.h>
  29 #include "cifspdu.h"
  30 #include "cifsglob.h"
  31 #include "cifsproto.h"
  32 #include "cifs_debug.h"
  33 #include "cifsfs.h"
  34
  35 #define CIFS_IOCTL_MAGIC        0xCF
  36 #define CIFS_IOC_COPYCHUNK_FILE _IOW(CIFS_IOCTL_MAGIC, 3, int)
  37
  38 static long cifs_ioctl_clone(unsigned int xid, struct file *dst_file,
  39                         unsigned long srcfd, u64 off, u64 len, u64 destoff)
  40 {
  41         int rc;
  42         struct cifsFileInfo *smb_file_target = dst_file->private_data;
  43         struct inode *target_inode = file_inode(dst_file);
  44         struct cifs_tcon *target_tcon;
  45         struct fd src_file;
  46         struct cifsFileInfo *smb_file_src;
  47         struct inode *src_inode;
  48         struct cifs_tcon *src_tcon;
  49
  50         cifs_dbg(FYI, "ioctl clone range\n");
  51         /* the destination must be opened for writing */
  52         if (!(dst_file->f_mode & FMODE_WRITE)) {
  53                 cifs_dbg(FYI, "file target not open for write\n");
  54                 return -EINVAL;
  55         }
  56
  57         /* check if target volume is readonly and take reference */
  58         rc = mnt_want_write_file(dst_file);
  59         if (rc) {
  60                 cifs_dbg(FYI, "mnt_want_write failed with rc %d\n", rc);
  61                 return rc;
  62         }
  63
  64         src_file = fdget(srcfd);
  65         if (!src_file.file) {
  66                 rc = -EBADF;
  67                 goto out_drop_write;
  68         }
  69
  70         if (src_file.file->f_op->unlocked_ioctl != cifs_ioctl) {
  71                 rc = -EBADF;
  72                 cifs_dbg(VFS, "src file seems to be from a different filesystem type\n");
  73                 goto out_fput;
  74         }
  75
  76         if ((!src_file.file->private_data) || (!dst_file->private_data)) {
  77                 rc = -EBADF;
  78                 cifs_dbg(VFS, "missing cifsFileInfo on copy range src file\n");
  79                 goto out_fput;
  80         }
  81
  82         rc = -EXDEV;
  83         smb_file_target = dst_file->private_data;
  84         smb_file_src = src_file.file->private_data;
  85         src_tcon = tlink_tcon(smb_file_src->tlink);
  86         target_tcon = tlink_tcon(smb_file_target->tlink);
  87
  88         /* check if source and target are on same tree connection */
  89         if (src_tcon != target_tcon) {
  90                 cifs_dbg(VFS, "file copy src and target on different volume\n");
  91                 goto out_fput;
  92         }
  93
  94         src_inode = file_inode(src_file.file);
  95         rc = -EINVAL;
  96         if (S_ISDIR(src_inode->i_mode))
  97                 goto out_fput;
  98
  99         /*
 100          * Note: cifs case is easier than btrfs since server responsible for
 101          * checks for proper open modes and file type and if it wants
 102          * server could even support copy of range where source = target
 103          */
 104         lock_two_nondirectories(target_inode, src_inode);
 105
 106         /* determine range to clone */
 107         rc = -EINVAL;
 108         if (off + len > src_inode->i_size || off + len < off)
 109                 goto out_unlock;
 110         if (len == 0)
 111                 len = src_inode->i_size - off;
 112
 113         cifs_dbg(FYI, "about to flush pages\n");
 114         /* should we flush first and last page first */
 115         truncate_inode_pages_range(&target_inode->i_data, destoff,
 116                                    PAGE_CACHE_ALIGN(destoff + len)-1);
 117
 118         if (target_tcon->ses->server->ops->clone_range)
 119                 rc = target_tcon->ses->server->ops->clone_range(xid,
 120                         smb_file_src, smb_file_target, off, len, destoff);
 121
 122         /* force revalidate of size and timestamps of target file now
 123            that target is updated on the server */
 124         CIFS_I(target_inode)->time = 0;
 125 out_unlock:
 126         /* although unlocking in the reverse order from locking is not
 127            strictly necessary here it is a little cleaner to be consistent */
 128         unlock_two_nondirectories(src_inode, target_inode);
 129 out_fput:
 130         fdput(src_file);
 131 out_drop_write:
 132         mnt_drop_write_file(dst_file);
 133         return rc;
 134 }
 135
 136 long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
 137 {
 138         struct inode *inode = file_inode(filep);
 139         int rc = -ENOTTY; /* strange error - but the precedent */
 140         unsigned int xid;
 141         struct cifs_sb_info *cifs_sb;
 142         struct cifsFileInfo *pSMBFile = filep->private_data;
 143         struct cifs_tcon *tcon;
 144         __u64   ExtAttrBits = 0;
 145         __u64   caps;
 146
 147         xid = get_xid();
 148
 149         cifs_dbg(FYI, "ioctl file %p  cmd %u  arg %lu\n", filep, command, arg);
 150
 151         cifs_sb = CIFS_SB(inode->i_sb);
 152
 153         switch (command) {
 154                 case FS_IOC_GETFLAGS:
 155                         if (pSMBFile == NULL)
 156                                 break;
 157                         tcon = tlink_tcon(pSMBFile->tlink);
 158                         caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
 159 #ifdef CONFIG_CIFS_POSIX
 160                         if (CIFS_UNIX_EXTATTR_CAP & caps) {
 161                                 __u64   ExtAttrMask = 0;
 162                                 rc = CIFSGetExtAttr(xid, tcon,
 163                                                     pSMBFile->fid.netfid,
 164                                                     &ExtAttrBits, &ExtAttrMask);
 165                                 if (rc == 0)
 166                                         rc = put_user(ExtAttrBits &
 167                                                 FS_FL_USER_VISIBLE,
 168                                                 (int __user *)arg);
 169                                 if (rc != EOPNOTSUPP)
 170                                         break;
 171                         }
 172 #endif /* CONFIG_CIFS_POSIX */
 173                         rc = 0;
 174                         if (CIFS_I(inode)->cifsAttrs & ATTR_COMPRESSED) {
 175                                 /* add in the compressed bit */
 176                                 ExtAttrBits = FS_COMPR_FL;
 177                                 rc = put_user(ExtAttrBits & FS_FL_USER_VISIBLE,
 178                                               (int __user *)arg);
 179                         }
 180                         break;
 181                 case FS_IOC_SETFLAGS:
 182                         if (pSMBFile == NULL)
 183                                 break;
 184                         tcon = tlink_tcon(pSMBFile->tlink);
 185                         caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
 186
 187                         if (get_user(ExtAttrBits, (int __user *)arg)) {
 188                                 rc = -EFAULT;
 189                                 break;
 190                         }
 191
 192                         /*
 193                          * if (CIFS_UNIX_EXTATTR_CAP & caps)
 194                          *      rc = CIFSSetExtAttr(xid, tcon,
 195                          *                     pSMBFile->fid.netfid,
 196                          *                     extAttrBits,
 197                          *                     &ExtAttrMask);
 198                          * if (rc != EOPNOTSUPP)
 199                          *      break;
 200                          */
 201
 202                         /* Currently only flag we can set is compressed flag */
 203                         if ((ExtAttrBits & FS_COMPR_FL) == 0)
 204                                 break;
 205
 206                         /* Try to set compress flag */
 207                         if (tcon->ses->server->ops->set_compression) {
 208                                 rc = tcon->ses->server->ops->set_compression(
 209                                                         xid, tcon, pSMBFile);
 210                                 cifs_dbg(FYI, "set compress flag rc %d\n", rc);
 211                         }
 212                         break;
 213                 case CIFS_IOC_COPYCHUNK_FILE:
 214                         rc = cifs_ioctl_clone(xid, filep, arg, 0, 0, 0);
 215                         break;
 216                 default:
 217                         cifs_dbg(FYI, "unsupported ioctl\n");
 218                         break;
 219         }
 220
 221         free_xid(xid);
 222         return rc;
 223 }