fs/smb/client/dfs_cache.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * DFS referral cache routines
   4  *
   5  * Copyright (c) 2018-2019 Paulo Alcantara <palcantara@suse.de>
   6  */
   7
   8 #ifndef _CIFS_DFS_CACHE_H
   9 #define _CIFS_DFS_CACHE_H
  10
  11 #include <linux/nls.h>
  12 #include <linux/list.h>
  13 #include <linux/uuid.h>
  14 #include "cifsglob.h"
  15
  16 extern struct workqueue_struct *dfscache_wq;
  17 extern atomic_t dfs_cache_ttl;
  18
  19 #define DFS_CACHE_TGT_LIST_INIT(var) \
  20         { .tl_numtgts = 0, .tl_list = LIST_HEAD_INIT((var).tl_list), }
  21
  22 #define DFS_CACHE_TGT_LIST(var) \
  23         struct dfs_cache_tgt_list var = DFS_CACHE_TGT_LIST_INIT(var)
  24
  25 struct dfs_cache_tgt_list {
  26         int tl_numtgts;
  27         struct list_head tl_list;
  28 };
  29
  30 struct dfs_cache_tgt_iterator {
  31         char *it_name;
  32         int it_path_consumed;
  33         struct list_head it_list;
  34 };
  35
  36 int dfs_cache_init(void);
  37 void dfs_cache_destroy(void);
  38 extern const struct proc_ops dfscache_proc_ops;
  39
  40 int dfs_cache_find(const unsigned int xid, struct cifs_ses *ses, const struct nls_table *cp,
  41                    int remap, const char *path, struct dfs_info3_param *ref,
  42                    struct dfs_cache_tgt_list *tgt_list);
  43 int dfs_cache_noreq_find(const char *path, struct dfs_info3_param *ref,
  44                          struct dfs_cache_tgt_list *tgt_list);
  45 void dfs_cache_noreq_update_tgthint(const char *path, const struct dfs_cache_tgt_iterator *it);
  46 int dfs_cache_get_tgt_referral(const char *path, const struct dfs_cache_tgt_iterator *it,
  47                                struct dfs_info3_param *ref);
  48 int dfs_cache_get_tgt_share(char *path, const struct dfs_cache_tgt_iterator *it, char **share,
  49                             char **prefix);
  50 char *dfs_cache_canonical_path(const char *path, const struct nls_table *cp, int remap);
  51 int dfs_cache_remount_fs(struct cifs_sb_info *cifs_sb);
  52 void dfs_cache_refresh(struct work_struct *work);
  53
  54 static inline struct dfs_cache_tgt_iterator *
  55 dfs_cache_get_next_tgt(struct dfs_cache_tgt_list *tl,
  56                        struct dfs_cache_tgt_iterator *it)
  57 {
  58         if (!tl || !tl->tl_numtgts || list_empty(&tl->tl_list) ||
  59             !it || list_is_last(&it->it_list, &tl->tl_list))
  60                 return NULL;
  61         return list_next_entry(it, it_list);
  62 }
  63
  64 static inline struct dfs_cache_tgt_iterator *
  65 dfs_cache_get_tgt_iterator(struct dfs_cache_tgt_list *tl)
  66 {
  67         if (!tl)
  68                 return NULL;
  69         return list_first_entry_or_null(&tl->tl_list,
  70                                         struct dfs_cache_tgt_iterator,
  71                                         it_list);
  72 }
  73
  74 static inline void dfs_cache_free_tgts(struct dfs_cache_tgt_list *tl)
  75 {
  76         struct dfs_cache_tgt_iterator *it, *nit;
  77
  78         if (!tl || !tl->tl_numtgts || list_empty(&tl->tl_list))
  79                 return;
  80         list_for_each_entry_safe(it, nit, &tl->tl_list, it_list) {
  81                 list_del(&it->it_list);
  82                 kfree(it->it_name);
  83                 kfree(it);
  84         }
  85         tl->tl_numtgts = 0;
  86 }
  87
  88 static inline const char *
  89 dfs_cache_get_tgt_name(const struct dfs_cache_tgt_iterator *it)
  90 {
  91         return it ? it->it_name : NULL;
  92 }
  93
  94 static inline int
  95 dfs_cache_get_nr_tgts(const struct dfs_cache_tgt_list *tl)
  96 {
  97         return tl ? tl->tl_numtgts : 0;
  98 }
  99
 100 static inline int dfs_cache_get_ttl(void)
 101 {
 102         return atomic_read(&dfs_cache_ttl);
 103 }
 104
 105 #endif /* _CIFS_DFS_CACHE_H */