fs/bad_inode.c

   1 /*
   2  *  linux/fs/bad_inode.c
   3  *
   4  *  Copyright (C) 1997, Stephen Tweedie
   5  *
   6  *  Provide stub functions for unreadable inodes
   7  *
   8  *  Fabian Frederick : August 2003 - All file operations assigned to EIO
   9  */
  10
  11 #include <linux/fs.h>
  12 #include <linux/module.h>
  13 #include <linux/stat.h>
  14 #include <linux/time.h>
  15 #include <linux/namei.h>
  16 #include <linux/poll.h>
  17
  18
  19 static loff_t bad_file_llseek(struct file *file, loff_t offset, int origin)
  20 {
  21         return -EIO;
  22 }
  23
  24 static ssize_t bad_file_read(struct file *filp, char __user *buf,
  25                         size_t size, loff_t *ppos)
  26 {
  27         return -EIO;
  28 }
  29
  30 static ssize_t bad_file_write(struct file *filp, const char __user *buf,
  31                         size_t siz, loff_t *ppos)
  32 {
  33         return -EIO;
  34 }
  35
  36 static ssize_t bad_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
  37                         unsigned long nr_segs, loff_t pos)
  38 {
  39         return -EIO;
  40 }
  41
  42 static ssize_t bad_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
  43                         unsigned long nr_segs, loff_t pos)
  44 {
  45         return -EIO;
  46 }
  47
  48 static int bad_file_readdir(struct file *filp, void *dirent, filldir_t filldir)
  49 {
  50         return -EIO;
  51 }
  52
  53 static unsigned int bad_file_poll(struct file *filp, poll_table *wait)
  54 {
  55         return POLLERR;
  56 }
  57
  58 static int bad_file_ioctl (struct inode *inode, struct file *filp,
  59                         unsigned int cmd, unsigned long arg)
  60 {
  61         return -EIO;
  62 }
  63
  64 static long bad_file_unlocked_ioctl(struct file *file, unsigned cmd,
  65                         unsigned long arg)
  66 {
  67         return -EIO;
  68 }
  69
  70 static long bad_file_compat_ioctl(struct file *file, unsigned int cmd,
  71                         unsigned long arg)
  72 {
  73         return -EIO;
  74 }
  75
  76 static int bad_file_mmap(struct file *file, struct vm_area_struct *vma)
  77 {
  78         return -EIO;
  79 }
  80
  81 static int bad_file_open(struct inode *inode, struct file *filp)
  82 {
  83         return -EIO;
  84 }
  85
  86 static int bad_file_flush(struct file *file, fl_owner_t id)
  87 {
  88         return -EIO;
  89 }
  90
  91 static int bad_file_release(struct inode *inode, struct file *filp)
  92 {
  93         return -EIO;
  94 }
  95
  96 static int bad_file_fsync(struct file *file, struct dentry *dentry,
  97                         int datasync)
  98 {
  99         return -EIO;
 100 }
 101
 102 static int bad_file_aio_fsync(struct kiocb *iocb, int datasync)
 103 {
 104         return -EIO;
 105 }
 106
 107 static int bad_file_fasync(int fd, struct file *filp, int on)
 108 {
 109         return -EIO;
 110 }
 111
 112 static int bad_file_lock(struct file *file, int cmd, struct file_lock *fl)
 113 {
 114         return -EIO;
 115 }
 116
 117 static ssize_t bad_file_sendfile(struct file *in_file, loff_t *ppos,
 118                         size_t count, read_actor_t actor, void *target)
 119 {
 120         return -EIO;
 121 }
 122
 123 static ssize_t bad_file_sendpage(struct file *file, struct page *page,
 124                         int off, size_t len, loff_t *pos, int more)
 125 {
 126         return -EIO;
 127 }
 128
 129 static unsigned long bad_file_get_unmapped_area(struct file *file,
 130                                 unsigned long addr, unsigned long len,
 131                                 unsigned long pgoff, unsigned long flags)
 132 {
 133         return -EIO;
 134 }
 135
 136 static int bad_file_check_flags(int flags)
 137 {
 138         return -EIO;
 139 }
 140
 141 static int bad_file_dir_notify(struct file *file, unsigned long arg)
 142 {
 143         return -EIO;
 144 }
 145
 146 static int bad_file_flock(struct file *filp, int cmd, struct file_lock *fl)
 147 {
 148         return -EIO;
 149 }
 150
 151 static ssize_t bad_file_splice_write(struct pipe_inode_info *pipe,
 152                         struct file *out, loff_t *ppos, size_t len,
 153                         unsigned int flags)
 154 {
 155         return -EIO;
 156 }
 157
 158 static ssize_t bad_file_splice_read(struct file *in, loff_t *ppos,
 159                         struct pipe_inode_info *pipe, size_t len,
 160                         unsigned int flags)
 161 {
 162         return -EIO;
 163 }
 164
 165 static const struct file_operations bad_file_ops =
 166 {
 167         .llseek         = bad_file_llseek,
 168         .read           = bad_file_read,
 169         .write          = bad_file_write,
 170         .aio_read       = bad_file_aio_read,
 171         .aio_write      = bad_file_aio_write,
 172         .readdir        = bad_file_readdir,
 173         .poll           = bad_file_poll,
 174         .ioctl          = bad_file_ioctl,
 175         .unlocked_ioctl = bad_file_unlocked_ioctl,
 176         .compat_ioctl   = bad_file_compat_ioctl,
 177         .mmap           = bad_file_mmap,
 178         .open           = bad_file_open,
 179         .flush          = bad_file_flush,
 180         .release        = bad_file_release,
 181         .fsync          = bad_file_fsync,
 182         .aio_fsync      = bad_file_aio_fsync,
 183         .fasync         = bad_file_fasync,
 184         .lock           = bad_file_lock,
 185         .sendfile       = bad_file_sendfile,
 186         .sendpage       = bad_file_sendpage,
 187         .get_unmapped_area = bad_file_get_unmapped_area,
 188         .check_flags    = bad_file_check_flags,
 189         .dir_notify     = bad_file_dir_notify,
 190         .flock          = bad_file_flock,
 191         .splice_write   = bad_file_splice_write,
 192         .splice_read    = bad_file_splice_read,
 193 };
 194
 195 static int bad_inode_create (struct inode *dir, struct dentry *dentry,
 196                 int mode, struct nameidata *nd)
 197 {
 198         return -EIO;
 199 }
 200
 201 static struct dentry *bad_inode_lookup(struct inode *dir,
 202                         struct dentry *dentry, struct nameidata *nd)
 203 {
 204         return ERR_PTR(-EIO);
 205 }
 206
 207 static int bad_inode_link (struct dentry *old_dentry, struct inode *dir,
 208                 struct dentry *dentry)
 209 {
 210         return -EIO;
 211 }
 212
 213 static int bad_inode_unlink(struct inode *dir, struct dentry *dentry)
 214 {
 215         return -EIO;
 216 }
 217
 218 static int bad_inode_symlink (struct inode *dir, struct dentry *dentry,
 219                 const char *symname)
 220 {
 221         return -EIO;
 222 }
 223
 224 static int bad_inode_mkdir(struct inode *dir, struct dentry *dentry,
 225                         int mode)
 226 {
 227         return -EIO;
 228 }
 229
 230 static int bad_inode_rmdir (struct inode *dir, struct dentry *dentry)
 231 {
 232         return -EIO;
 233 }
 234
 235 static int bad_inode_mknod (struct inode *dir, struct dentry *dentry,
 236                         int mode, dev_t rdev)
 237 {
 238         return -EIO;
 239 }
 240
 241 static int bad_inode_rename (struct inode *old_dir, struct dentry *old_dentry,
 242                 struct inode *new_dir, struct dentry *new_dentry)
 243 {
 244         return -EIO;
 245 }
 246
 247 static int bad_inode_readlink(struct dentry *dentry, char __user *buffer,
 248                 int buflen)
 249 {
 250         return -EIO;
 251 }
 252
 253 static int bad_inode_permission(struct inode *inode, int mask,
 254                         struct nameidata *nd)
 255 {
 256         return -EIO;
 257 }
 258
 259 static int bad_inode_getattr(struct vfsmount *mnt, struct dentry *dentry,
 260                         struct kstat *stat)
 261 {
 262         return -EIO;
 263 }
 264
 265 static int bad_inode_setattr(struct dentry *direntry, struct iattr *attrs)
 266 {
 267         return -EIO;
 268 }
 269
 270 static int bad_inode_setxattr(struct dentry *dentry, const char *name,
 271                 const void *value, size_t size, int flags)
 272 {
 273         return -EIO;
 274 }
 275
 276 static ssize_t bad_inode_getxattr(struct dentry *dentry, const char *name,
 277                         void *buffer, size_t size)
 278 {
 279         return -EIO;
 280 }
 281
 282 static ssize_t bad_inode_listxattr(struct dentry *dentry, char *buffer,
 283                         size_t buffer_size)
 284 {
 285         return -EIO;
 286 }
 287
 288 static int bad_inode_removexattr(struct dentry *dentry, const char *name)
 289 {
 290         return -EIO;
 291 }
 292
 293 static const struct inode_operations bad_inode_ops =
 294 {
 295         .create         = bad_inode_create,
 296         .lookup         = bad_inode_lookup,
 297         .link           = bad_inode_link,
 298         .unlink         = bad_inode_unlink,
 299         .symlink        = bad_inode_symlink,
 300         .mkdir          = bad_inode_mkdir,
 301         .rmdir          = bad_inode_rmdir,
 302         .mknod          = bad_inode_mknod,
 303         .rename         = bad_inode_rename,
 304         .readlink       = bad_inode_readlink,
 305         /* follow_link must be no-op, otherwise unmounting this inode
 306            won't work */
 307         /* put_link returns void */
 308         /* truncate returns void */
 309         .permission     = bad_inode_permission,
 310         .getattr        = bad_inode_getattr,
 311         .setattr        = bad_inode_setattr,
 312         .setxattr       = bad_inode_setxattr,
 313         .getxattr       = bad_inode_getxattr,
 314         .listxattr      = bad_inode_listxattr,
 315         .removexattr    = bad_inode_removexattr,
 316         /* truncate_range returns void */
 317 };
 318
 319
 320 /*
 321  * When a filesystem is unable to read an inode due to an I/O error in
 322  * its read_inode() function, it can call make_bad_inode() to return a
 323  * set of stubs which will return EIO errors as required.
 324  *
 325  * We only need to do limited initialisation: all other fields are
 326  * preinitialised to zero automatically.
 327  */
 328
 329 /**
 330  *      make_bad_inode - mark an inode bad due to an I/O error
 331  *      @inode: Inode to mark bad
 332  *
 333  *      When an inode cannot be read due to a media or remote network
 334  *      failure this function makes the inode "bad" and causes I/O operations
 335  *      on it to fail from this point on.
 336  */
 337
 338 void make_bad_inode(struct inode *inode)
 339 {
 340         remove_inode_hash(inode);
 341
 342         inode->i_mode = S_IFREG;
 343         inode->i_atime = inode->i_mtime = inode->i_ctime =
 344                 current_fs_time(inode->i_sb);
 345         inode->i_op = &bad_inode_ops;
 346         inode->i_fop = &bad_file_ops;
 347 }
 348 EXPORT_SYMBOL(make_bad_inode);
 349
 350 /*
 351  * This tests whether an inode has been flagged as bad. The test uses
 352  * &bad_inode_ops to cover the case of invalidated inodes as well as
 353  * those created by make_bad_inode() above.
 354  */
 355
 356 /**
 357  *      is_bad_inode - is an inode errored
 358  *      @inode: inode to test
 359  *
 360  *      Returns true if the inode in question has been marked as bad.
 361  */
 362
 363 int is_bad_inode(struct inode *inode)
 364 {
 365         return (inode->i_op == &bad_inode_ops);
 366 }
 367
 368 EXPORT_SYMBOL(is_bad_inode);