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 #define DFS_CACHE_TGT_LIST_INIT(var) { .tl_numtgts = 0, .tl_list = LIST_HEAD_INIT((var).tl_list), }
17 
18 struct dfs_cache_tgt_list {
19 	int tl_numtgts;
20 	struct list_head tl_list;
21 };
22 
23 struct dfs_cache_tgt_iterator {
24 	char *it_name;
25 	int it_path_consumed;
26 	struct list_head it_list;
27 };
28 
29 int dfs_cache_init(void);
30 void dfs_cache_destroy(void);
31 extern const struct proc_ops dfscache_proc_ops;
32 
33 int dfs_cache_find(const unsigned int xid, struct cifs_ses *ses, const struct nls_table *cp,
34 		   int remap, const char *path, struct dfs_info3_param *ref,
35 		   struct dfs_cache_tgt_list *tgt_list);
36 int dfs_cache_noreq_find(const char *path, struct dfs_info3_param *ref,
37 			 struct dfs_cache_tgt_list *tgt_list);
38 int dfs_cache_update_tgthint(const unsigned int xid, struct cifs_ses *ses,
39 			     const struct nls_table *cp, int remap, const char *path,
40 			     const struct dfs_cache_tgt_iterator *it);
41 int dfs_cache_noreq_update_tgthint(const char *path, const struct dfs_cache_tgt_iterator *it);
42 int dfs_cache_get_tgt_referral(const char *path, const struct dfs_cache_tgt_iterator *it,
43 			       struct dfs_info3_param *ref);
44 int dfs_cache_get_tgt_share(char *path, const struct dfs_cache_tgt_iterator *it, char **share,
45 			    char **prefix);
46 void dfs_cache_put_refsrv_sessions(const uuid_t *mount_id);
47 void dfs_cache_add_refsrv_session(const uuid_t *mount_id, struct cifs_ses *ses);
48 char *dfs_cache_canonical_path(const char *path, const struct nls_table *cp, int remap);
49 int dfs_cache_remount_fs(struct cifs_sb_info *cifs_sb);
50 
51 static inline struct dfs_cache_tgt_iterator *
dfs_cache_get_next_tgt(struct dfs_cache_tgt_list * tl,struct dfs_cache_tgt_iterator * it)52 dfs_cache_get_next_tgt(struct dfs_cache_tgt_list *tl,
53 		       struct dfs_cache_tgt_iterator *it)
54 {
55 	if (!tl || list_empty(&tl->tl_list) || !it ||
56 	    list_is_last(&it->it_list, &tl->tl_list))
57 		return NULL;
58 	return list_next_entry(it, it_list);
59 }
60 
61 static inline struct dfs_cache_tgt_iterator *
dfs_cache_get_tgt_iterator(struct dfs_cache_tgt_list * tl)62 dfs_cache_get_tgt_iterator(struct dfs_cache_tgt_list *tl)
63 {
64 	if (!tl)
65 		return NULL;
66 	return list_first_entry_or_null(&tl->tl_list,
67 					struct dfs_cache_tgt_iterator,
68 					it_list);
69 }
70 
dfs_cache_free_tgts(struct dfs_cache_tgt_list * tl)71 static inline void dfs_cache_free_tgts(struct dfs_cache_tgt_list *tl)
72 {
73 	struct dfs_cache_tgt_iterator *it, *nit;
74 
75 	if (!tl || list_empty(&tl->tl_list))
76 		return;
77 	list_for_each_entry_safe(it, nit, &tl->tl_list, it_list) {
78 		list_del(&it->it_list);
79 		kfree(it->it_name);
80 		kfree(it);
81 	}
82 	tl->tl_numtgts = 0;
83 }
84 
85 static inline const char *
dfs_cache_get_tgt_name(const struct dfs_cache_tgt_iterator * it)86 dfs_cache_get_tgt_name(const struct dfs_cache_tgt_iterator *it)
87 {
88 	return it ? it->it_name : NULL;
89 }
90 
91 static inline int
dfs_cache_get_nr_tgts(const struct dfs_cache_tgt_list * tl)92 dfs_cache_get_nr_tgts(const struct dfs_cache_tgt_list *tl)
93 {
94 	return tl ? tl->tl_numtgts : 0;
95 }
96 
97 #endif /* _CIFS_DFS_CACHE_H */
98