fs/xfs/libxfs/xfs_parent.h

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2022-2024 Oracle.
   4  * All Rights Reserved.
   5  */
   6 #ifndef __XFS_PARENT_H__
   7 #define __XFS_PARENT_H__
   8
   9 /* Metadata validators */
  10 bool xfs_parent_namecheck(unsigned int attr_flags, const void *name,
  11                 size_t length);
  12 bool xfs_parent_valuecheck(struct xfs_mount *mp, const void *value,
  13                 size_t valuelen);
  14
  15 xfs_dahash_t xfs_parent_hashval(struct xfs_mount *mp, const uint8_t *name,
  16                 int namelen, xfs_ino_t parent_ino);
  17 xfs_dahash_t xfs_parent_hashattr(struct xfs_mount *mp, const uint8_t *name,
  18                 int namelen, const void *value, int valuelen);
  19
  20 /* Initializes a xfs_parent_rec to be stored as an attribute name. */
  21 static inline void
  22 xfs_parent_rec_init(
  23         struct xfs_parent_rec   *rec,
  24         xfs_ino_t               ino,
  25         uint32_t                gen)
  26 {
  27         rec->p_ino = cpu_to_be64(ino);
  28         rec->p_gen = cpu_to_be32(gen);
  29 }
  30
  31 /* Initializes a xfs_parent_rec to be stored as an attribute name. */
  32 static inline void
  33 xfs_inode_to_parent_rec(
  34         struct xfs_parent_rec   *rec,
  35         const struct xfs_inode  *dp)
  36 {
  37         xfs_parent_rec_init(rec, dp->i_ino, VFS_IC(dp)->i_generation);
  38 }
  39
  40 extern struct kmem_cache        *xfs_parent_args_cache;
  41
  42 /*
  43  * Parent pointer information needed to pass around the deferred xattr update
  44  * machinery.
  45  */
  46 struct xfs_parent_args {
  47         struct xfs_parent_rec   rec;
  48         struct xfs_parent_rec   new_rec;
  49         struct xfs_da_args      args;
  50 };
  51
  52 /*
  53  * Start a parent pointer update by allocating the context object we need to
  54  * perform a parent pointer update.
  55  */
  56 static inline int
  57 xfs_parent_start(
  58         struct xfs_mount        *mp,
  59         struct xfs_parent_args  **ppargsp)
  60 {
  61         if (!xfs_has_parent(mp)) {
  62                 *ppargsp = NULL;
  63                 return 0;
  64         }
  65
  66         *ppargsp = kmem_cache_zalloc(xfs_parent_args_cache, GFP_KERNEL);
  67         if (!*ppargsp)
  68                 return -ENOMEM;
  69         return 0;
  70 }
  71
  72 /* Finish a parent pointer update by freeing the context object. */
  73 static inline void
  74 xfs_parent_finish(
  75         struct xfs_mount        *mp,
  76         struct xfs_parent_args  *ppargs)
  77 {
  78         if (ppargs)
  79                 kmem_cache_free(xfs_parent_args_cache, ppargs);
  80 }
  81
  82 int xfs_parent_addname(struct xfs_trans *tp, struct xfs_parent_args *ppargs,
  83                 struct xfs_inode *dp, const struct xfs_name *parent_name,
  84                 struct xfs_inode *child);
  85 int xfs_parent_removename(struct xfs_trans *tp, struct xfs_parent_args *ppargs,
  86                 struct xfs_inode *dp, const struct xfs_name *parent_name,
  87                 struct xfs_inode *child);
  88 int xfs_parent_replacename(struct xfs_trans *tp,
  89                 struct xfs_parent_args *ppargs,
  90                 struct xfs_inode *old_dp, const struct xfs_name *old_name,
  91                 struct xfs_inode *new_dp, const struct xfs_name *new_name,
  92                 struct xfs_inode *child);
  93
  94 int xfs_parent_from_attr(struct xfs_mount *mp, unsigned int attr_flags,
  95                 const unsigned char *name, unsigned int namelen,
  96                 const void *value, unsigned int valuelen,
  97                 xfs_ino_t *parent_ino, uint32_t *parent_gen);
  98
  99 /* Repair functions */
 100 int xfs_parent_lookup(struct xfs_trans *tp, struct xfs_inode *ip,
 101                 const struct xfs_name *name, struct xfs_parent_rec *pptr,
 102                 struct xfs_da_args *scratch);
 103 int xfs_parent_set(struct xfs_inode *ip, xfs_ino_t owner,
 104                 const struct xfs_name *name, struct xfs_parent_rec *pptr,
 105                 struct xfs_da_args *scratch);
 106 int xfs_parent_unset(struct xfs_inode *ip, xfs_ino_t owner,
 107                 const struct xfs_name *name, struct xfs_parent_rec *pptr,
 108                 struct xfs_da_args *scratch);
 109
 110 #endif /* __XFS_PARENT_H__ */