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 = (1 << 0), 16 __OVL_PATH_UPPER = (1 << 1), 17 __OVL_PATH_MERGE = (1 << 2), 18 }; 19 20 #define OVL_TYPE_UPPER(type) ((type) & __OVL_PATH_UPPER) 21 #define OVL_TYPE_MERGE(type) ((type) & __OVL_PATH_MERGE) 22 #define OVL_TYPE_PURE_UPPER(type) ((type) & __OVL_PATH_PURE) 23 #define OVL_TYPE_MERGE_OR_LOWER(type) \ 24 (OVL_TYPE_MERGE(type) || !OVL_TYPE_UPPER(type)) 25 26 #define OVL_XATTR_PRE_NAME "trusted.overlay." 27 #define OVL_XATTR_PRE_LEN 16 28 #define OVL_XATTR_OPAQUE OVL_XATTR_PRE_NAME"opaque" 29 30 static inline int ovl_do_rmdir(struct inode *dir, struct dentry *dentry) 31 { 32 int err = vfs_rmdir(dir, dentry); 33 pr_debug("rmdir(%pd2) = %i\n", dentry, err); 34 return err; 35 } 36 37 static inline int ovl_do_unlink(struct inode *dir, struct dentry *dentry) 38 { 39 int err = vfs_unlink(dir, dentry, NULL); 40 pr_debug("unlink(%pd2) = %i\n", dentry, err); 41 return err; 42 } 43 44 static inline int ovl_do_link(struct dentry *old_dentry, struct inode *dir, 45 struct dentry *new_dentry, bool debug) 46 { 47 int err = vfs_link(old_dentry, dir, new_dentry, NULL); 48 if (debug) { 49 pr_debug("link(%pd2, %pd2) = %i\n", 50 old_dentry, new_dentry, err); 51 } 52 return err; 53 } 54 55 static inline int ovl_do_create(struct inode *dir, struct dentry *dentry, 56 umode_t mode, bool debug) 57 { 58 int err = vfs_create(dir, dentry, mode, true); 59 if (debug) 60 pr_debug("create(%pd2, 0%o) = %i\n", dentry, mode, err); 61 return err; 62 } 63 64 static inline int ovl_do_mkdir(struct inode *dir, struct dentry *dentry, 65 umode_t mode, bool debug) 66 { 67 int err = vfs_mkdir(dir, dentry, mode); 68 if (debug) 69 pr_debug("mkdir(%pd2, 0%o) = %i\n", dentry, mode, err); 70 return err; 71 } 72 73 static inline int ovl_do_mknod(struct inode *dir, struct dentry *dentry, 74 umode_t mode, dev_t dev, bool debug) 75 { 76 int err = vfs_mknod(dir, dentry, mode, dev); 77 if (debug) { 78 pr_debug("mknod(%pd2, 0%o, 0%o) = %i\n", 79 dentry, mode, dev, err); 80 } 81 return err; 82 } 83 84 static inline int ovl_do_symlink(struct inode *dir, struct dentry *dentry, 85 const char *oldname, bool debug) 86 { 87 int err = vfs_symlink(dir, dentry, oldname); 88 if (debug) 89 pr_debug("symlink(\"%s\", %pd2) = %i\n", oldname, dentry, err); 90 return err; 91 } 92 93 static inline int ovl_do_setxattr(struct dentry *dentry, const char *name, 94 const void *value, size_t size, int flags) 95 { 96 int err = vfs_setxattr(dentry, name, value, size, flags); 97 pr_debug("setxattr(%pd2, \"%s\", \"%*s\", 0x%x) = %i\n", 98 dentry, name, (int) size, (char *) value, flags, err); 99 return err; 100 } 101 102 static inline int ovl_do_removexattr(struct dentry *dentry, const char *name) 103 { 104 int err = vfs_removexattr(dentry, name); 105 pr_debug("removexattr(%pd2, \"%s\") = %i\n", dentry, name, err); 106 return err; 107 } 108 109 static inline int ovl_do_rename(struct inode *olddir, struct dentry *olddentry, 110 struct inode *newdir, struct dentry *newdentry, 111 unsigned int flags) 112 { 113 int err; 114 115 pr_debug("rename2(%pd2, %pd2, 0x%x)\n", 116 olddentry, newdentry, flags); 117 118 err = vfs_rename(olddir, olddentry, newdir, newdentry, NULL, flags); 119 120 if (err) { 121 pr_debug("...rename2(%pd2, %pd2, ...) = %i\n", 122 olddentry, newdentry, err); 123 } 124 return err; 125 } 126 127 static inline int ovl_do_whiteout(struct inode *dir, struct dentry *dentry) 128 { 129 int err = vfs_whiteout(dir, dentry); 130 pr_debug("whiteout(%pd2) = %i\n", dentry, err); 131 return err; 132 } 133 134 enum ovl_path_type ovl_path_type(struct dentry *dentry); 135 u64 ovl_dentry_version_get(struct dentry *dentry); 136 void ovl_dentry_version_inc(struct dentry *dentry); 137 void ovl_path_upper(struct dentry *dentry, struct path *path); 138 void ovl_path_lower(struct dentry *dentry, struct path *path); 139 enum ovl_path_type ovl_path_real(struct dentry *dentry, struct path *path); 140 int ovl_path_next(int idx, struct dentry *dentry, struct path *path); 141 struct dentry *ovl_dentry_upper(struct dentry *dentry); 142 struct dentry *ovl_dentry_lower(struct dentry *dentry); 143 struct dentry *ovl_dentry_real(struct dentry *dentry); 144 struct dentry *ovl_entry_real(struct ovl_entry *oe, bool *is_upper); 145 struct vfsmount *ovl_entry_mnt_real(struct ovl_entry *oe, struct inode *inode, 146 bool is_upper); 147 struct ovl_dir_cache *ovl_dir_cache(struct dentry *dentry); 148 bool ovl_is_default_permissions(struct inode *inode); 149 void ovl_set_dir_cache(struct dentry *dentry, struct ovl_dir_cache *cache); 150 struct dentry *ovl_workdir(struct dentry *dentry); 151 int ovl_want_write(struct dentry *dentry); 152 void ovl_drop_write(struct dentry *dentry); 153 bool ovl_dentry_is_opaque(struct dentry *dentry); 154 void ovl_dentry_set_opaque(struct dentry *dentry, bool opaque); 155 bool ovl_is_whiteout(struct dentry *dentry); 156 const struct cred *ovl_override_creds(struct super_block *sb); 157 void ovl_dentry_update(struct dentry *dentry, struct dentry *upperdentry); 158 struct dentry *ovl_lookup(struct inode *dir, struct dentry *dentry, 159 unsigned int flags); 160 struct file *ovl_path_open(struct path *path, int flags); 161 162 struct dentry *ovl_upper_create(struct dentry *upperdir, struct dentry *dentry, 163 struct kstat *stat, const char *link); 164 165 /* readdir.c */ 166 extern const struct file_operations ovl_dir_operations; 167 int ovl_check_empty_dir(struct dentry *dentry, struct list_head *list); 168 void ovl_cleanup_whiteouts(struct dentry *upper, struct list_head *list); 169 void ovl_cache_free(struct list_head *list); 170 int ovl_check_d_type_supported(struct path *realpath); 171 172 /* inode.c */ 173 int ovl_setattr(struct dentry *dentry, struct iattr *attr); 174 int ovl_permission(struct inode *inode, int mask); 175 int ovl_setxattr(struct dentry *dentry, struct inode *inode, 176 const char *name, const void *value, 177 size_t size, int flags); 178 ssize_t ovl_getxattr(struct dentry *dentry, struct inode *inode, 179 const char *name, void *value, size_t size); 180 ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size); 181 int ovl_removexattr(struct dentry *dentry, const char *name); 182 struct inode *ovl_d_select_inode(struct dentry *dentry, unsigned file_flags); 183 184 struct inode *ovl_new_inode(struct super_block *sb, umode_t mode, 185 struct ovl_entry *oe); 186 static inline void ovl_copyattr(struct inode *from, struct inode *to) 187 { 188 to->i_uid = from->i_uid; 189 to->i_gid = from->i_gid; 190 to->i_mode = from->i_mode; 191 } 192 193 /* dir.c */ 194 extern const struct inode_operations ovl_dir_inode_operations; 195 struct dentry *ovl_lookup_temp(struct dentry *workdir, struct dentry *dentry); 196 int ovl_create_real(struct inode *dir, struct dentry *newdentry, 197 struct kstat *stat, const char *link, 198 struct dentry *hardlink, bool debug); 199 void ovl_cleanup(struct inode *dir, struct dentry *dentry); 200 201 /* copy_up.c */ 202 int ovl_copy_up(struct dentry *dentry); 203 int ovl_copy_up_one(struct dentry *parent, struct dentry *dentry, 204 struct path *lowerpath, struct kstat *stat); 205 int ovl_copy_xattr(struct dentry *old, struct dentry *new); 206 int ovl_set_attr(struct dentry *upper, struct kstat *stat); 207