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1/* SPDX-License-Identifier: GPL-2.0 */2/*3 * Copyright (c) 2022 Paulo Alcantara <palcantara@suse.de>4 */5 6#ifndef _CIFS_DFS_H7#define _CIFS_DFS_H8 9#include "cifsglob.h"10#include "cifsproto.h"11#include "fs_context.h"12#include "dfs_cache.h"13#include "cifs_unicode.h"14#include <linux/namei.h>15 16#define DFS_INTERLINK(v) \17 (((v) & DFSREF_REFERRAL_SERVER) && !((v) & DFSREF_STORAGE_SERVER))18 19struct dfs_ref {20 char *path;21 char *full_path;22 struct cifs_ses *ses;23 struct dfs_cache_tgt_list tl;24 struct dfs_cache_tgt_iterator *tit;25};26 27struct dfs_ref_walk {28 struct dfs_ref *ref;29 struct dfs_ref refs[MAX_NESTED_LINKS];30};31 32#define ref_walk_start(w) ((w)->refs)33#define ref_walk_end(w) (&(w)->refs[ARRAY_SIZE((w)->refs) - 1])34#define ref_walk_cur(w) ((w)->ref)35#define ref_walk_descend(w) (--ref_walk_cur(w) >= ref_walk_start(w))36 37#define ref_walk_tit(w) (ref_walk_cur(w)->tit)38#define ref_walk_empty(w) (!ref_walk_tit(w))39#define ref_walk_path(w) (ref_walk_cur(w)->path)40#define ref_walk_fpath(w) (ref_walk_cur(w)->full_path)41#define ref_walk_tl(w) (&ref_walk_cur(w)->tl)42#define ref_walk_ses(w) (ref_walk_cur(w)->ses)43 44static inline struct dfs_ref_walk *ref_walk_alloc(void)45{46 struct dfs_ref_walk *rw;47 48 rw = kmalloc(sizeof(*rw), GFP_KERNEL);49 if (!rw)50 return ERR_PTR(-ENOMEM);51 return rw;52}53 54static inline void ref_walk_init(struct dfs_ref_walk *rw)55{56 memset(rw, 0, sizeof(*rw));57 ref_walk_cur(rw) = ref_walk_start(rw);58}59 60static inline void __ref_walk_free(struct dfs_ref *ref)61{62 kfree(ref->path);63 kfree(ref->full_path);64 dfs_cache_free_tgts(&ref->tl);65 if (ref->ses)66 cifs_put_smb_ses(ref->ses);67 memset(ref, 0, sizeof(*ref));68}69 70static inline void ref_walk_free(struct dfs_ref_walk *rw)71{72 struct dfs_ref *ref;73 74 if (!rw)75 return;76 77 for (ref = ref_walk_start(rw); ref <= ref_walk_end(rw); ref++)78 __ref_walk_free(ref);79 kfree(rw);80}81 82static inline int ref_walk_advance(struct dfs_ref_walk *rw)83{84 struct dfs_ref *ref = ref_walk_cur(rw) + 1;85 86 if (ref > ref_walk_end(rw))87 return -ELOOP;88 __ref_walk_free(ref);89 ref_walk_cur(rw) = ref;90 return 0;91}92 93static inline struct dfs_cache_tgt_iterator *94ref_walk_next_tgt(struct dfs_ref_walk *rw)95{96 struct dfs_cache_tgt_iterator *tit;97 struct dfs_ref *ref = ref_walk_cur(rw);98 99 if (!ref->tit)100 tit = dfs_cache_get_tgt_iterator(&ref->tl);101 else102 tit = dfs_cache_get_next_tgt(&ref->tl, ref->tit);103 ref->tit = tit;104 return tit;105}106 107static inline int ref_walk_get_tgt(struct dfs_ref_walk *rw,108 struct dfs_info3_param *tgt)109{110 zfree_dfs_info_param(tgt);111 return dfs_cache_get_tgt_referral(ref_walk_path(rw) + 1,112 ref_walk_tit(rw), tgt);113}114 115static inline int ref_walk_num_tgts(struct dfs_ref_walk *rw)116{117 return dfs_cache_get_nr_tgts(ref_walk_tl(rw));118}119 120static inline void ref_walk_set_tgt_hint(struct dfs_ref_walk *rw)121{122 dfs_cache_noreq_update_tgthint(ref_walk_path(rw) + 1,123 ref_walk_tit(rw));124}125 126static inline void ref_walk_set_tcon(struct dfs_ref_walk *rw,127 struct cifs_tcon *tcon)128{129 struct dfs_ref *ref = ref_walk_start(rw);130 131 for (; ref <= ref_walk_cur(rw); ref++) {132 if (WARN_ON_ONCE(!ref->ses))133 continue;134 list_add(&ref->ses->dlist, &tcon->dfs_ses_list);135 ref->ses = NULL;136 }137}138 139int dfs_parse_target_referral(const char *full_path, const struct dfs_info3_param *ref,140 struct smb3_fs_context *ctx);141int dfs_mount_share(struct cifs_mount_ctx *mnt_ctx);142 143static inline char *dfs_get_path(struct cifs_sb_info *cifs_sb, const char *path)144{145 return dfs_cache_canonical_path(path, cifs_sb->local_nls, cifs_remap(cifs_sb));146}147 148static inline int dfs_get_referral(struct cifs_mount_ctx *mnt_ctx, const char *path,149 struct dfs_info3_param *ref, struct dfs_cache_tgt_list *tl)150{151 struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;152 struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;153 struct cifs_ses *rses = ctx->dfs_root_ses ?: mnt_ctx->ses;154 155 return dfs_cache_find(mnt_ctx->xid, rses, cifs_sb->local_nls,156 cifs_remap(cifs_sb), path, ref, tl);157}158 159/*160 * cifs_get_smb_ses() already guarantees an active reference of161 * @ses->dfs_root_ses when a new session is created, so we need to put extra162 * references of all DFS root sessions that were used across the mount process163 * in dfs_mount_share().164 */165static inline void dfs_put_root_smb_sessions(struct list_head *head)166{167 struct cifs_ses *ses, *n;168 169 list_for_each_entry_safe(ses, n, head, dlist) {170 list_del_init(&ses->dlist);171 cifs_put_smb_ses(ses);172 }173}174 175#endif /* _CIFS_DFS_H */176