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 #include <linux/btrfs.h>
  35
  36 #define CIFS_IOCTL_MAGIC        0xCF
  37 #define CIFS_IOC_COPYCHUNK_FILE _IOW(CIFS_IOCTL_MAGIC, 3, int)
  38 #define CIFS_IOC_SET_INTEGRITY  _IO(CIFS_IOCTL_MAGIC, 4)
  39
  40 static long cifs_ioctl_clone(unsigned int xid, struct file *dst_file,
  41                         unsigned long srcfd, u64 off, u64 len, u64 destoff,
  42                         bool dup_extents)
  43 {
  44         int rc;
  45         struct cifsFileInfo *smb_file_target = dst_file->private_data;
  46         struct inode *target_inode = file_inode(dst_file);
  47         struct cifs_tcon *target_tcon;
  48         struct fd src_file;
  49         struct cifsFileInfo *smb_file_src;
  50         struct inode *src_inode;
  51         struct cifs_tcon *src_tcon;
  52
  53         cifs_dbg(FYI, "ioctl clone range\n");
  54         /* the destination must be opened for writing */
  55         if (!(dst_file->f_mode & FMODE_WRITE)) {
  56                 cifs_dbg(FYI, "file target not open for write\n");
  57                 return -EINVAL;
  58         }
  59
  60         /* check if target volume is readonly and take reference */
  61         rc = mnt_want_write_file(dst_file);
  62         if (rc) {
  63                 cifs_dbg(FYI, "mnt_want_write failed with rc %d\n", rc);
  64                 return rc;
  65         }
  66
  67         src_file = fdget(srcfd);
  68         if (!src_file.file) {
  69                 rc = -EBADF;
  70                 goto out_drop_write;
  71         }
  72
  73         if ((!src_file.file->private_data) || (!dst_file->private_data)) {
  74                 rc = -EBADF;
  75                 cifs_dbg(VFS, "missing cifsFileInfo on copy range src file\n");
  76                 goto out_fput;
  77         }
  78
  79         rc = -EXDEV;
  80         smb_file_target = dst_file->private_data;
  81         smb_file_src = src_file.file->private_data;
  82         src_tcon = tlink_tcon(smb_file_src->tlink);
  83         target_tcon = tlink_tcon(smb_file_target->tlink);
  84
  85         /* check if source and target are on same tree connection */
  86         if (src_tcon != target_tcon) {
  87                 cifs_dbg(VFS, "file copy src and target on different volume\n");
  88                 goto out_fput;
  89         }
  90
  91         src_inode = file_inode(src_file.file);
  92         rc = -EINVAL;
  93         if (S_ISDIR(src_inode->i_mode))
  94                 goto out_fput;
  95
  96         /*
  97          * Note: cifs case is easier than btrfs since server responsible for
  98          * checks for proper open modes and file type and if it wants
  99          * server could even support copy of range where source = target
 100          */
 101         lock_two_nondirectories(target_inode, src_inode);
 102
 103         /* determine range to clone */
 104         rc = -EINVAL;
 105         if (off + len > src_inode->i_size || off + len < off)
 106                 goto out_unlock;
 107         if (len == 0)
 108                 len = src_inode->i_size - off;
 109
 110         cifs_dbg(FYI, "about to flush pages\n");
 111         /* should we flush first and last page first */
 112         truncate_inode_pages_range(&target_inode->i_data, destoff,
 113                                    PAGE_CACHE_ALIGN(destoff + len)-1);
 114
 115         if (dup_extents && target_tcon->ses->server->ops->duplicate_extents)
 116                 rc = target_tcon->ses->server->ops->duplicate_extents(xid,
 117                         smb_file_src, smb_file_target, off, len, destoff);
 118         else if (!dup_extents && 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         else
 122                 rc = -EOPNOTSUPP;
 123
 124         /* force revalidate of size and timestamps of target file now
 125            that target is updated on the server */
 126         CIFS_I(target_inode)->time = 0;
 127 out_unlock:
 128         /* although unlocking in the reverse order from locking is not
 129            strictly necessary here it is a little cleaner to be consistent */
 130         unlock_two_nondirectories(src_inode, target_inode);
 131 out_fput:
 132         fdput(src_file);
 133 out_drop_write:
 134         mnt_drop_write_file(dst_file);
 135         return rc;
 136 }
 137
 138 long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
 139 {
 140         struct inode *inode = file_inode(filep);
 141         int rc = -ENOTTY; /* strange error - but the precedent */
 142         unsigned int xid;
 143         struct cifs_sb_info *cifs_sb;
 144         struct cifsFileInfo *pSMBFile = filep->private_data;
 145         struct cifs_tcon *tcon;
 146         __u64   ExtAttrBits = 0;
 147         __u64   caps;
 148
 149         xid = get_xid();
 150
 151         cifs_dbg(FYI, "ioctl file %p  cmd %u  arg %lu\n", filep, command, arg);
 152
 153         cifs_sb = CIFS_SB(inode->i_sb);
 154
 155         switch (command) {
 156                 case FS_IOC_GETFLAGS:
 157                         if (pSMBFile == NULL)
 158                                 break;
 159                         tcon = tlink_tcon(pSMBFile->tlink);
 160                         caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
 161 #ifdef CONFIG_CIFS_POSIX
 162                         if (CIFS_UNIX_EXTATTR_CAP & caps) {
 163                                 __u64   ExtAttrMask = 0;
 164                                 rc = CIFSGetExtAttr(xid, tcon,
 165                                                     pSMBFile->fid.netfid,
 166                                                     &ExtAttrBits, &ExtAttrMask);
 167                                 if (rc == 0)
 168                                         rc = put_user(ExtAttrBits &
 169                                                 FS_FL_USER_VISIBLE,
 170                                                 (int __user *)arg);
 171                                 if (rc != EOPNOTSUPP)
 172                                         break;
 173                         }
 174 #endif /* CONFIG_CIFS_POSIX */
 175                         rc = 0;
 176                         if (CIFS_I(inode)->cifsAttrs & ATTR_COMPRESSED) {
 177                                 /* add in the compressed bit */
 178                                 ExtAttrBits = FS_COMPR_FL;
 179                                 rc = put_user(ExtAttrBits & FS_FL_USER_VISIBLE,
 180                                               (int __user *)arg);
 181                         }
 182                         break;
 183                 case FS_IOC_SETFLAGS:
 184                         if (pSMBFile == NULL)
 185                                 break;
 186                         tcon = tlink_tcon(pSMBFile->tlink);
 187                         caps = le64_to_cpu(tcon->fsUnixInfo.Capability);
 188
 189                         if (get_user(ExtAttrBits, (int __user *)arg)) {
 190                                 rc = -EFAULT;
 191                                 break;
 192                         }
 193
 194                         /*
 195                          * if (CIFS_UNIX_EXTATTR_CAP & caps)
 196                          *      rc = CIFSSetExtAttr(xid, tcon,
 197                          *                     pSMBFile->fid.netfid,
 198                          *                     extAttrBits,
 199                          *                     &ExtAttrMask);
 200                          * if (rc != EOPNOTSUPP)
 201                          *      break;
 202                          */
 203
 204                         /* Currently only flag we can set is compressed flag */
 205                         if ((ExtAttrBits & FS_COMPR_FL) == 0)
 206                                 break;
 207
 208                         /* Try to set compress flag */
 209                         if (tcon->ses->server->ops->set_compression) {
 210                                 rc = tcon->ses->server->ops->set_compression(
 211                                                         xid, tcon, pSMBFile);
 212                                 cifs_dbg(FYI, "set compress flag rc %d\n", rc);
 213                         }
 214                         break;
 215                 case CIFS_IOC_COPYCHUNK_FILE:
 216                         rc = cifs_ioctl_clone(xid, filep, arg, 0, 0, 0, false);
 217                         break;
 218                 case BTRFS_IOC_CLONE:
 219                         rc = cifs_ioctl_clone(xid, filep, arg, 0, 0, 0, true);
 220                         break;
 221                 case CIFS_IOC_SET_INTEGRITY:
 222                         if (pSMBFile == NULL)
 223                                 break;
 224                         tcon = tlink_tcon(pSMBFile->tlink);
 225                         if (tcon->ses->server->ops->set_integrity)
 226                                 rc = tcon->ses->server->ops->set_integrity(xid,
 227                                                 tcon, pSMBFile);
 228                         else
 229                                 rc = -EOPNOTSUPP;
 230                         break;
 231                 default:
 232                         cifs_dbg(FYI, "unsupported ioctl\n");
 233                         break;
 234         }
 235
 236         free_xid(xid);
 237         return rc;
 238 }