fs/erofs/xattr.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (C) 2017-2018 HUAWEI, Inc.
   4  *             https://www.huawei.com/
   5  */
   6 #ifndef __EROFS_XATTR_H
   7 #define __EROFS_XATTR_H
   8
   9 #include "internal.h"
  10 #include <linux/posix_acl_xattr.h>
  11 #include <linux/xattr.h>
  12
  13 /* Attribute not found */
  14 #define ENOATTR         ENODATA
  15
  16 static inline unsigned int inlinexattr_header_size(struct inode *inode)
  17 {
  18         return sizeof(struct erofs_xattr_ibody_header) +
  19                 sizeof(u32) * EROFS_I(inode)->xattr_shared_count;
  20 }
  21
  22 static inline erofs_blk_t xattrblock_addr(struct erofs_sb_info *sbi,
  23                                           unsigned int xattr_id)
  24 {
  25 #ifdef CONFIG_EROFS_FS_XATTR
  26         return sbi->xattr_blkaddr +
  27                 xattr_id * sizeof(__u32) / EROFS_BLKSIZ;
  28 #else
  29         return 0;
  30 #endif
  31 }
  32
  33 static inline unsigned int xattrblock_offset(struct erofs_sb_info *sbi,
  34                                              unsigned int xattr_id)
  35 {
  36         return (xattr_id * sizeof(__u32)) % EROFS_BLKSIZ;
  37 }
  38
  39 #ifdef CONFIG_EROFS_FS_XATTR
  40 extern const struct xattr_handler erofs_xattr_user_handler;
  41 extern const struct xattr_handler erofs_xattr_trusted_handler;
  42 extern const struct xattr_handler erofs_xattr_security_handler;
  43
  44 static inline const char *erofs_xattr_prefix(unsigned int idx,
  45                                              struct dentry *dentry)
  46 {
  47         const struct xattr_handler *handler = NULL;
  48
  49         static const struct xattr_handler *xattr_handler_map[] = {
  50                 [EROFS_XATTR_INDEX_USER] = &erofs_xattr_user_handler,
  51 #ifdef CONFIG_EROFS_FS_POSIX_ACL
  52                 [EROFS_XATTR_INDEX_POSIX_ACL_ACCESS] = &nop_posix_acl_access,
  53                 [EROFS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &nop_posix_acl_default,
  54 #endif
  55                 [EROFS_XATTR_INDEX_TRUSTED] = &erofs_xattr_trusted_handler,
  56 #ifdef CONFIG_EROFS_FS_SECURITY
  57                 [EROFS_XATTR_INDEX_SECURITY] = &erofs_xattr_security_handler,
  58 #endif
  59         };
  60
  61         if (idx && idx < ARRAY_SIZE(xattr_handler_map))
  62                 handler = xattr_handler_map[idx];
  63
  64         if (!xattr_handler_can_list(handler, dentry))
  65                 return NULL;
  66
  67         return xattr_prefix(handler);
  68 }
  69
  70 extern const struct xattr_handler *erofs_xattr_handlers[];
  71
  72 int erofs_getxattr(struct inode *, int, const char *, void *, size_t);
  73 ssize_t erofs_listxattr(struct dentry *, char *, size_t);
  74 #else
  75 static inline int erofs_getxattr(struct inode *inode, int index,
  76                                  const char *name, void *buffer,
  77                                  size_t buffer_size)
  78 {
  79         return -EOPNOTSUPP;
  80 }
  81
  82 #define erofs_listxattr (NULL)
  83 #define erofs_xattr_handlers (NULL)
  84 #endif  /* !CONFIG_EROFS_FS_XATTR */
  85
  86 #ifdef CONFIG_EROFS_FS_POSIX_ACL
  87 struct posix_acl *erofs_get_acl(struct inode *inode, int type, bool rcu);
  88 #else
  89 #define erofs_get_acl   (NULL)
  90 #endif
  91
  92 #endif