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/export.h>
  13 #include <linux/stat.h>
  14 #include <linux/time.h>
  15 #include <linux/namei.h>
  16 #include <linux/poll.h>
  17
  18 static int bad_file_open(struct inode *inode, struct file *filp)
  19 {
  20         return -EIO;
  21 }
  22
  23 static const struct file_operations bad_file_ops =
  24 {
  25         .open           = bad_file_open,
  26 };
  27
  28 static int bad_inode_create (struct inode *dir, struct dentry *dentry,
  29                 umode_t mode, bool excl)
  30 {
  31         return -EIO;
  32 }
  33
  34 static struct dentry *bad_inode_lookup(struct inode *dir,
  35                         struct dentry *dentry, unsigned int flags)
  36 {
  37         return ERR_PTR(-EIO);
  38 }
  39
  40 static int bad_inode_link (struct dentry *old_dentry, struct inode *dir,
  41                 struct dentry *dentry)
  42 {
  43         return -EIO;
  44 }
  45
  46 static int bad_inode_unlink(struct inode *dir, struct dentry *dentry)
  47 {
  48         return -EIO;
  49 }
  50
  51 static int bad_inode_symlink (struct inode *dir, struct dentry *dentry,
  52                 const char *symname)
  53 {
  54         return -EIO;
  55 }
  56
  57 static int bad_inode_mkdir(struct inode *dir, struct dentry *dentry,
  58                         umode_t mode)
  59 {
  60         return -EIO;
  61 }
  62
  63 static int bad_inode_rmdir (struct inode *dir, struct dentry *dentry)
  64 {
  65         return -EIO;
  66 }
  67
  68 static int bad_inode_mknod (struct inode *dir, struct dentry *dentry,
  69                         umode_t mode, dev_t rdev)
  70 {
  71         return -EIO;
  72 }
  73
  74 static int bad_inode_rename2(struct inode *old_dir, struct dentry *old_dentry,
  75                              struct inode *new_dir, struct dentry *new_dentry,
  76                              unsigned int flags)
  77 {
  78         return -EIO;
  79 }
  80
  81 static int bad_inode_readlink(struct dentry *dentry, char __user *buffer,
  82                 int buflen)
  83 {
  84         return -EIO;
  85 }
  86
  87 static int bad_inode_permission(struct inode *inode, int mask)
  88 {
  89         return -EIO;
  90 }
  91
  92 static int bad_inode_getattr(struct vfsmount *mnt, struct dentry *dentry,
  93                         struct kstat *stat)
  94 {
  95         return -EIO;
  96 }
  97
  98 static int bad_inode_setattr(struct dentry *direntry, struct iattr *attrs)
  99 {
 100         return -EIO;
 101 }
 102
 103 static ssize_t bad_inode_listxattr(struct dentry *dentry, char *buffer,
 104                         size_t buffer_size)
 105 {
 106         return -EIO;
 107 }
 108
 109 static const char *bad_inode_get_link(struct dentry *dentry,
 110                                       struct inode *inode,
 111                                       struct delayed_call *done)
 112 {
 113         return ERR_PTR(-EIO);
 114 }
 115
 116 static struct posix_acl *bad_inode_get_acl(struct inode *inode, int type)
 117 {
 118         return ERR_PTR(-EIO);
 119 }
 120
 121 static int bad_inode_fiemap(struct inode *inode,
 122                             struct fiemap_extent_info *fieinfo, u64 start,
 123                             u64 len)
 124 {
 125         return -EIO;
 126 }
 127
 128 static int bad_inode_update_time(struct inode *inode, struct timespec *time,
 129                                  int flags)
 130 {
 131         return -EIO;
 132 }
 133
 134 static int bad_inode_atomic_open(struct inode *inode, struct dentry *dentry,
 135                                  struct file *file, unsigned int open_flag,
 136                                  umode_t create_mode, int *opened)
 137 {
 138         return -EIO;
 139 }
 140
 141 static int bad_inode_tmpfile(struct inode *inode, struct dentry *dentry,
 142                              umode_t mode)
 143 {
 144         return -EIO;
 145 }
 146
 147 static int bad_inode_set_acl(struct inode *inode, struct posix_acl *acl,
 148                              int type)
 149 {
 150         return -EIO;
 151 }
 152
 153 static const struct inode_operations bad_inode_ops =
 154 {
 155         .create         = bad_inode_create,
 156         .lookup         = bad_inode_lookup,
 157         .link           = bad_inode_link,
 158         .unlink         = bad_inode_unlink,
 159         .symlink        = bad_inode_symlink,
 160         .mkdir          = bad_inode_mkdir,
 161         .rmdir          = bad_inode_rmdir,
 162         .mknod          = bad_inode_mknod,
 163         .rename         = bad_inode_rename2,
 164         .readlink       = bad_inode_readlink,
 165         .permission     = bad_inode_permission,
 166         .getattr        = bad_inode_getattr,
 167         .setattr        = bad_inode_setattr,
 168         .listxattr      = bad_inode_listxattr,
 169         .get_link       = bad_inode_get_link,
 170         .get_acl        = bad_inode_get_acl,
 171         .fiemap         = bad_inode_fiemap,
 172         .update_time    = bad_inode_update_time,
 173         .atomic_open    = bad_inode_atomic_open,
 174         .tmpfile        = bad_inode_tmpfile,
 175         .set_acl        = bad_inode_set_acl,
 176 };
 177
 178
 179 /*
 180  * When a filesystem is unable to read an inode due to an I/O error in
 181  * its read_inode() function, it can call make_bad_inode() to return a
 182  * set of stubs which will return EIO errors as required.
 183  *
 184  * We only need to do limited initialisation: all other fields are
 185  * preinitialised to zero automatically.
 186  */
 187
 188 /**
 189  *      make_bad_inode - mark an inode bad due to an I/O error
 190  *      @inode: Inode to mark bad
 191  *
 192  *      When an inode cannot be read due to a media or remote network
 193  *      failure this function makes the inode "bad" and causes I/O operations
 194  *      on it to fail from this point on.
 195  */
 196
 197 void make_bad_inode(struct inode *inode)
 198 {
 199         remove_inode_hash(inode);
 200
 201         inode->i_mode = S_IFREG;
 202         inode->i_atime = inode->i_mtime = inode->i_ctime =
 203                 current_time(inode);
 204         inode->i_op = &bad_inode_ops;
 205         inode->i_opflags &= ~IOP_XATTR;
 206         inode->i_fop = &bad_file_ops;
 207 }
 208 EXPORT_SYMBOL(make_bad_inode);
 209
 210 /*
 211  * This tests whether an inode has been flagged as bad. The test uses
 212  * &bad_inode_ops to cover the case of invalidated inodes as well as
 213  * those created by make_bad_inode() above.
 214  */
 215
 216 /**
 217  *      is_bad_inode - is an inode errored
 218  *      @inode: inode to test
 219  *
 220  *      Returns true if the inode in question has been marked as bad.
 221  */
 222
 223 bool is_bad_inode(struct inode *inode)
 224 {
 225         return (inode->i_op == &bad_inode_ops);
 226 }
 227
 228 EXPORT_SYMBOL(is_bad_inode);
 229
 230 /**
 231  * iget_failed - Mark an under-construction inode as dead and release it
 232  * @inode: The inode to discard
 233  *
 234  * Mark an under-construction inode as dead and release it.
 235  */
 236 void iget_failed(struct inode *inode)
 237 {
 238         make_bad_inode(inode);
 239         unlock_new_inode(inode);
 240         iput(inode);
 241 }
 242 EXPORT_SYMBOL(iget_failed);