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