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
 16extern struct workqueue_struct *dfscache_wq;
 17extern 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
 25struct dfs_cache_tgt_list {
 26	int tl_numtgts;
 27	struct list_head tl_list;
 28};
 29
 30struct dfs_cache_tgt_iterator {
 31	char *it_name;
 32	int it_path_consumed;
 33	struct list_head it_list;
 34};
 35
 36int dfs_cache_init(void);
 37void dfs_cache_destroy(void);
 38extern const struct proc_ops dfscache_proc_ops;
 39
 40int 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);
 43int dfs_cache_noreq_find(const char *path, struct dfs_info3_param *ref,
 44			 struct dfs_cache_tgt_list *tgt_list);
 45void dfs_cache_noreq_update_tgthint(const char *path, const struct dfs_cache_tgt_iterator *it);
 46int dfs_cache_get_tgt_referral(const char *path, const struct dfs_cache_tgt_iterator *it,
 47			       struct dfs_info3_param *ref);
 48int dfs_cache_get_tgt_share(char *path, const struct dfs_cache_tgt_iterator *it, char **share,
 49			    char **prefix);
 50char *dfs_cache_canonical_path(const char *path, const struct nls_table *cp, int remap);
 51int dfs_cache_remount_fs(struct cifs_sb_info *cifs_sb);
 52void dfs_cache_refresh(struct work_struct *work);
 53
 54static inline struct dfs_cache_tgt_iterator *
 55dfs_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
 64static inline struct dfs_cache_tgt_iterator *
 65dfs_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
 74static 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
 88static inline const char *
 89dfs_cache_get_tgt_name(const struct dfs_cache_tgt_iterator *it)
 90{
 91	return it ? it->it_name : NULL;
 92}
 93
 94static inline int
 95dfs_cache_get_nr_tgts(const struct dfs_cache_tgt_list *tl)
 96{
 97	return tl ? tl->tl_numtgts : 0;
 98}
 99
100static inline int dfs_cache_get_ttl(void)
101{
102	return atomic_read(&dfs_cache_ttl);
103}
104
105#endif /* _CIFS_DFS_CACHE_H */