fs/overlayfs/overlayfs.h

   1 /*
   2  *
   3  * Copyright (C) 2011 Novell Inc.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 as published by
   7  * the Free Software Foundation.
   8  */
   9
  10 #include <linux/kernel.h>
  11
  12 struct ovl_entry;
  13
  14 enum ovl_path_type {
  15         OVL_PATH_PURE_UPPER,
  16         OVL_PATH_UPPER,
  17         OVL_PATH_MERGE,
  18         OVL_PATH_LOWER,
  19 };
  20
  21 extern const char *ovl_opaque_xattr;
  22
  23 static inline int ovl_do_rmdir(struct inode *dir, struct dentry *dentry)
  24 {
  25         int err = vfs_rmdir(dir, dentry);
  26         pr_debug("rmdir(%pd2) = %i\n", dentry, err);
  27         return err;
  28 }
  29
  30 static inline int ovl_do_unlink(struct inode *dir, struct dentry *dentry)
  31 {
  32         int err = vfs_unlink(dir, dentry, NULL);
  33         pr_debug("unlink(%pd2) = %i\n", dentry, err);
  34         return err;
  35 }
  36
  37 static inline int ovl_do_link(struct dentry *old_dentry, struct inode *dir,
  38                               struct dentry *new_dentry, bool debug)
  39 {
  40         int err = vfs_link(old_dentry, dir, new_dentry, NULL);
  41         if (debug) {
  42                 pr_debug("link(%pd2, %pd2) = %i\n",
  43                          old_dentry, new_dentry, err);
  44         }
  45         return err;
  46 }
  47
  48 static inline int ovl_do_create(struct inode *dir, struct dentry *dentry,
  49                              umode_t mode, bool debug)
  50 {
  51         int err = vfs_create(dir, dentry, mode, true);
  52         if (debug)
  53                 pr_debug("create(%pd2, 0%o) = %i\n", dentry, mode, err);
  54         return err;
  55 }
  56
  57 static inline int ovl_do_mkdir(struct inode *dir, struct dentry *dentry,
  58                                umode_t mode, bool debug)
  59 {
  60         int err = vfs_mkdir(dir, dentry, mode);
  61         if (debug)
  62                 pr_debug("mkdir(%pd2, 0%o) = %i\n", dentry, mode, err);
  63         return err;
  64 }
  65
  66 static inline int ovl_do_mknod(struct inode *dir, struct dentry *dentry,
  67                                umode_t mode, dev_t dev, bool debug)
  68 {
  69         int err = vfs_mknod(dir, dentry, mode, dev);
  70         if (debug) {
  71                 pr_debug("mknod(%pd2, 0%o, 0%o) = %i\n",
  72                          dentry, mode, dev, err);
  73         }
  74         return err;
  75 }
  76
  77 static inline int ovl_do_symlink(struct inode *dir, struct dentry *dentry,
  78                                  const char *oldname, bool debug)
  79 {
  80         int err = vfs_symlink(dir, dentry, oldname);
  81         if (debug)
  82                 pr_debug("symlink(\"%s\", %pd2) = %i\n", oldname, dentry, err);
  83         return err;
  84 }
  85
  86 static inline int ovl_do_setxattr(struct dentry *dentry, const char *name,
  87                                   const void *value, size_t size, int flags)
  88 {
  89         int err = vfs_setxattr(dentry, name, value, size, flags);
  90         pr_debug("setxattr(%pd2, \"%s\", \"%*s\", 0x%x) = %i\n",
  91                  dentry, name, (int) size, (char *) value, flags, err);
  92         return err;
  93 }
  94
  95 static inline int ovl_do_removexattr(struct dentry *dentry, const char *name)
  96 {
  97         int err = vfs_removexattr(dentry, name);
  98         pr_debug("removexattr(%pd2, \"%s\") = %i\n", dentry, name, err);
  99         return err;
 100 }
 101
 102 static inline int ovl_do_rename(struct inode *olddir, struct dentry *olddentry,
 103                                 struct inode *newdir, struct dentry *newdentry,
 104                                 unsigned int flags)
 105 {
 106         int err;
 107
 108         pr_debug("rename2(%pd2, %pd2, 0x%x)\n",
 109                  olddentry, newdentry, flags);
 110
 111         err = vfs_rename(olddir, olddentry, newdir, newdentry, NULL, flags);
 112
 113         if (err) {
 114                 pr_debug("...rename2(%pd2, %pd2, ...) = %i\n",
 115                          olddentry, newdentry, err);
 116         }
 117         return err;
 118 }
 119
 120 static inline int ovl_do_whiteout(struct inode *dir, struct dentry *dentry)
 121 {
 122         int err = vfs_whiteout(dir, dentry);
 123         pr_debug("whiteout(%pd2) = %i\n", dentry, err);
 124         return err;
 125 }
 126
 127 enum ovl_path_type ovl_path_type(struct dentry *dentry);
 128 u64 ovl_dentry_version_get(struct dentry *dentry);
 129 void ovl_dentry_version_inc(struct dentry *dentry);
 130 void ovl_path_upper(struct dentry *dentry, struct path *path);
 131 void ovl_path_lower(struct dentry *dentry, struct path *path);
 132 enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path);
 133 struct dentry *ovl_dentry_upper(struct dentry *dentry);
 134 struct dentry *ovl_dentry_lower(struct dentry *dentry);
 135 struct dentry *ovl_dentry_real(struct dentry *dentry);
 136 struct dentry *ovl_entry_real(struct ovl_entry *oe, bool *is_upper);
 137 struct ovl_dir_cache *ovl_dir_cache(struct dentry *dentry);
 138 void ovl_set_dir_cache(struct dentry *dentry, struct ovl_dir_cache *cache);
 139 struct dentry *ovl_workdir(struct dentry *dentry);
 140 int ovl_want_write(struct dentry *dentry);
 141 void ovl_drop_write(struct dentry *dentry);
 142 bool ovl_dentry_is_opaque(struct dentry *dentry);
 143 void ovl_dentry_set_opaque(struct dentry *dentry, bool opaque);
 144 bool ovl_is_whiteout(struct dentry *dentry);
 145 void ovl_dentry_update(struct dentry *dentry, struct dentry *upperdentry);
 146 struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry,
 147                           unsigned int flags);
 148 struct file *ovl_path_open(struct path *path, int flags);
 149
 150 struct dentry *ovl_upper_create(struct dentry *upperdir, struct dentry *dentry,
 151                                 struct kstat *stat, const char *link);
 152
 153 /* readdir.c */
 154 extern const struct file_operations ovl_dir_operations;
 155 int ovl_check_empty_dir(struct dentry *dentry, struct list_head *list);
 156 void ovl_cleanup_whiteouts(struct dentry *upper, struct list_head *list);
 157 void ovl_cache_free(struct list_head *list);
 158
 159 /* inode.c */
 160 int ovl_setattr(struct dentry *dentry, struct iattr *attr);
 161 int ovl_permission(struct inode *inode, int mask);
 162 int ovl_setxattr(struct dentry *dentry, const char *name,
 163                  const void *value, size_t size, int flags);
 164 ssize_t ovl_getxattr(struct dentry *dentry, const char *name,
 165                      void *value, size_t size);
 166 ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size);
 167 int ovl_removexattr(struct dentry *dentry, const char *name);
 168
 169 struct inode *ovl_new_inode(struct super_block *sb, umode_t mode,
 170                             struct ovl_entry *oe);
 171 static inline void ovl_copyattr(struct inode *from, struct inode *to)
 172 {
 173         to->i_uid = from->i_uid;
 174         to->i_gid = from->i_gid;
 175 }
 176
 177 /* dir.c */
 178 extern const struct inode_operations ovl_dir_inode_operations;
 179 struct dentry *ovl_lookup_temp(struct dentry *workdir, struct dentry *dentry);
 180 int ovl_create_real(struct inode *dir, struct dentry *newdentry,
 181                     struct kstat *stat, const char *link,
 182                     struct dentry *hardlink, bool debug);
 183 void ovl_cleanup(struct inode *dir, struct dentry *dentry);
 184
 185 /* copy_up.c */
 186 int ovl_copy_up(struct dentry *dentry);
 187 int ovl_copy_up_one(struct dentry *parent, struct dentry *dentry,
 188                     struct path *lowerpath, struct kstat *stat,
 189                     struct iattr *attr);
 190 int ovl_copy_xattr(struct dentry *old, struct dentry *new);
 191 int ovl_set_attr(struct dentry *upper, struct kstat *stat);