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_sendpage(struct file *file, struct page *page,
 118                         int off, size_t len, loff_t *pos, int more)
 119 {
 120         return -EIO;
 121 }
 122
 123 static unsigned long bad_file_get_unmapped_area(struct file *file,
 124                                 unsigned long addr, unsigned long len,
 125                                 unsigned long pgoff, unsigned long flags)
 126 {
 127         return -EIO;
 128 }
 129
 130 static int bad_file_check_flags(int flags)
 131 {
 132         return -EIO;
 133 }
 134
 135 static int bad_file_dir_notify(struct file *file, unsigned long arg)
 136 {
 137         return -EIO;
 138 }
 139
 140 static int bad_file_flock(struct file *filp, int cmd, struct file_lock *fl)
 141 {
 142         return -EIO;
 143 }
 144
 145 static ssize_t bad_file_splice_write(struct pipe_inode_info *pipe,
 146                         struct file *out, loff_t *ppos, size_t len,
 147                         unsigned int flags)
 148 {
 149         return -EIO;
 150 }
 151
 152 static ssize_t bad_file_splice_read(struct file *in, loff_t *ppos,
 153                         struct pipe_inode_info *pipe, size_t len,
 154                         unsigned int flags)
 155 {
 156         return -EIO;
 157 }
 158
 159 static const struct file_operations bad_file_ops =
 160 {
 161         .llseek         = bad_file_llseek,
 162         .read           = bad_file_read,
 163         .write          = bad_file_write,
 164         .aio_read       = bad_file_aio_read,
 165         .aio_write      = bad_file_aio_write,
 166         .readdir        = bad_file_readdir,
 167         .poll           = bad_file_poll,
 168         .ioctl          = bad_file_ioctl,
 169         .unlocked_ioctl = bad_file_unlocked_ioctl,
 170         .compat_ioctl   = bad_file_compat_ioctl,
 171         .mmap           = bad_file_mmap,
 172         .open           = bad_file_open,
 173         .flush          = bad_file_flush,
 174         .release        = bad_file_release,
 175         .fsync          = bad_file_fsync,
 176         .aio_fsync      = bad_file_aio_fsync,
 177         .fasync         = bad_file_fasync,
 178         .lock           = bad_file_lock,
 179         .sendpage       = bad_file_sendpage,
 180         .get_unmapped_area = bad_file_get_unmapped_area,
 181         .check_flags    = bad_file_check_flags,
 182         .dir_notify     = bad_file_dir_notify,
 183         .flock          = bad_file_flock,
 184         .splice_write   = bad_file_splice_write,
 185         .splice_read    = bad_file_splice_read,
 186 };
 187
 188 static int bad_inode_create (struct inode *dir, struct dentry *dentry,
 189                 int mode, struct nameidata *nd)
 190 {
 191         return -EIO;
 192 }
 193
 194 static struct dentry *bad_inode_lookup(struct inode *dir,
 195                         struct dentry *dentry, struct nameidata *nd)
 196 {
 197         return ERR_PTR(-EIO);
 198 }
 199
 200 static int bad_inode_link (struct dentry *old_dentry, struct inode *dir,
 201                 struct dentry *dentry)
 202 {
 203         return -EIO;
 204 }
 205
 206 static int bad_inode_unlink(struct inode *dir, struct dentry *dentry)
 207 {
 208         return -EIO;
 209 }
 210
 211 static int bad_inode_symlink (struct inode *dir, struct dentry *dentry,
 212                 const char *symname)
 213 {
 214         return -EIO;
 215 }
 216
 217 static int bad_inode_mkdir(struct inode *dir, struct dentry *dentry,
 218                         int mode)
 219 {
 220         return -EIO;
 221 }
 222
 223 static int bad_inode_rmdir (struct inode *dir, struct dentry *dentry)
 224 {
 225         return -EIO;
 226 }
 227
 228 static int bad_inode_mknod (struct inode *dir, struct dentry *dentry,
 229                         int mode, dev_t rdev)
 230 {
 231         return -EIO;
 232 }
 233
 234 static int bad_inode_rename (struct inode *old_dir, struct dentry *old_dentry,
 235                 struct inode *new_dir, struct dentry *new_dentry)
 236 {
 237         return -EIO;
 238 }
 239
 240 static int bad_inode_readlink(struct dentry *dentry, char __user *buffer,
 241                 int buflen)
 242 {
 243         return -EIO;
 244 }
 245
 246 static int bad_inode_permission(struct inode *inode, int mask,
 247                         struct nameidata *nd)
 248 {
 249         return -EIO;
 250 }
 251
 252 static int bad_inode_getattr(struct vfsmount *mnt, struct dentry *dentry,
 253                         struct kstat *stat)
 254 {
 255         return -EIO;
 256 }
 257
 258 static int bad_inode_setattr(struct dentry *direntry, struct iattr *attrs)
 259 {
 260         return -EIO;
 261 }
 262
 263 static int bad_inode_setxattr(struct dentry *dentry, const char *name,
 264                 const void *value, size_t size, int flags)
 265 {
 266         return -EIO;
 267 }
 268
 269 static ssize_t bad_inode_getxattr(struct dentry *dentry, const char *name,
 270                         void *buffer, size_t size)
 271 {
 272         return -EIO;
 273 }
 274
 275 static ssize_t bad_inode_listxattr(struct dentry *dentry, char *buffer,
 276                         size_t buffer_size)
 277 {
 278         return -EIO;
 279 }
 280
 281 static int bad_inode_removexattr(struct dentry *dentry, const char *name)
 282 {
 283         return -EIO;
 284 }
 285
 286 static const struct inode_operations bad_inode_ops =
 287 {
 288         .create         = bad_inode_create,
 289         .lookup         = bad_inode_lookup,
 290         .link           = bad_inode_link,
 291         .unlink         = bad_inode_unlink,
 292         .symlink        = bad_inode_symlink,
 293         .mkdir          = bad_inode_mkdir,
 294         .rmdir          = bad_inode_rmdir,
 295         .mknod          = bad_inode_mknod,
 296         .rename         = bad_inode_rename,
 297         .readlink       = bad_inode_readlink,
 298         /* follow_link must be no-op, otherwise unmounting this inode
 299            won't work */
 300         /* put_link returns void */
 301         /* truncate returns void */
 302         .permission     = bad_inode_permission,
 303         .getattr        = bad_inode_getattr,
 304         .setattr        = bad_inode_setattr,
 305         .setxattr       = bad_inode_setxattr,
 306         .getxattr       = bad_inode_getxattr,
 307         .listxattr      = bad_inode_listxattr,
 308         .removexattr    = bad_inode_removexattr,
 309         /* truncate_range returns void */
 310 };
 311
 312
 313 /*
 314  * When a filesystem is unable to read an inode due to an I/O error in
 315  * its read_inode() function, it can call make_bad_inode() to return a
 316  * set of stubs which will return EIO errors as required.
 317  *
 318  * We only need to do limited initialisation: all other fields are
 319  * preinitialised to zero automatically.
 320  */
 321
 322 /**
 323  *      make_bad_inode - mark an inode bad due to an I/O error
 324  *      @inode: Inode to mark bad
 325  *
 326  *      When an inode cannot be read due to a media or remote network
 327  *      failure this function makes the inode "bad" and causes I/O operations
 328  *      on it to fail from this point on.
 329  */
 330
 331 void make_bad_inode(struct inode *inode)
 332 {
 333         remove_inode_hash(inode);
 334
 335         inode->i_mode = S_IFREG;
 336         inode->i_atime = inode->i_mtime = inode->i_ctime =
 337                 current_fs_time(inode->i_sb);
 338         inode->i_op = &bad_inode_ops;
 339         inode->i_fop = &bad_file_ops;
 340 }
 341 EXPORT_SYMBOL(make_bad_inode);
 342
 343 /*
 344  * This tests whether an inode has been flagged as bad. The test uses
 345  * &bad_inode_ops to cover the case of invalidated inodes as well as
 346  * those created by make_bad_inode() above.
 347  */
 348
 349 /**
 350  *      is_bad_inode - is an inode errored
 351  *      @inode: inode to test
 352  *
 353  *      Returns true if the inode in question has been marked as bad.
 354  */
 355
 356 int is_bad_inode(struct inode *inode)
 357 {
 358         return (inode->i_op == &bad_inode_ops);
 359 }
 360
 361 EXPORT_SYMBOL(is_bad_inode);