fs/ext2/acl.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3   File: fs/ext2/acl.h
   4
   5   (C) 2001 Andreas Gruenbacher, <a.gruenbacher@computer.org>
   6 */
   7
   8 #include <linux/posix_acl_xattr.h>
   9
  10 #define EXT2_ACL_VERSION        0x0001
  11
  12 typedef struct {
  13         __le16          e_tag;
  14         __le16          e_perm;
  15         __le32          e_id;
  16 } ext2_acl_entry;
  17
  18 typedef struct {
  19         __le16          e_tag;
  20         __le16          e_perm;
  21 } ext2_acl_entry_short;
  22
  23 typedef struct {
  24         __le32          a_version;
  25 } ext2_acl_header;
  26
  27 static inline size_t ext2_acl_size(int count)
  28 {
  29         if (count <= 4) {
  30                 return sizeof(ext2_acl_header) +
  31                        count * sizeof(ext2_acl_entry_short);
  32         } else {
  33                 return sizeof(ext2_acl_header) +
  34                        4 * sizeof(ext2_acl_entry_short) +
  35                        (count - 4) * sizeof(ext2_acl_entry);
  36         }
  37 }
  38
  39 static inline int ext2_acl_count(size_t size)
  40 {
  41         ssize_t s;
  42         size -= sizeof(ext2_acl_header);
  43         s = size - 4 * sizeof(ext2_acl_entry_short);
  44         if (s < 0) {
  45                 if (size % sizeof(ext2_acl_entry_short))
  46                         return -1;
  47                 return size / sizeof(ext2_acl_entry_short);
  48         } else {
  49                 if (s % sizeof(ext2_acl_entry))
  50                         return -1;
  51                 return s / sizeof(ext2_acl_entry) + 4;
  52         }
  53 }
  54
  55 #ifdef CONFIG_EXT2_FS_POSIX_ACL
  56
  57 /* acl.c */
  58 extern struct posix_acl *ext2_get_acl(struct inode *inode, int type);
  59 extern int ext2_set_acl(struct inode *inode, struct posix_acl *acl, int type);
  60 extern int ext2_init_acl (struct inode *, struct inode *);
  61
  62 #else
  63 #include <linux/sched.h>
  64 #define ext2_get_acl    NULL
  65 #define ext2_set_acl    NULL
  66
  67 static inline int ext2_init_acl (struct inode *inode, struct inode *dir)
  68 {
  69         return 0;
  70 }
  71 #endif
  72