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 */
106