linux/fs/cifs/dfs_cache.h
Paulo Alcantara (SUSE) bacd704a95 cifs: handle prefix paths in reconnect
For the case where we have a DFS path like below and we're currently
connected to targetA:

    //dfsroot/link -> //targetA/share/foo, //targetB/share/bar

after failover, we should make sure to update cifs_sb->prepath so the
next operations will use the new prefix path "/bar".

Besides, in order to simplify the use of different prefix paths,
enforce CIFS_MOUNT_USE_PREFIX_PATH for DFS mounts so we don't have to
revalidate the root dentry every time we set a new prefix path.

Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2020-03-22 22:49:09 -05:00

103 lines
2.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* DFS referral cache routines
*
* Copyright (c) 2018-2019 Paulo Alcantara <palcantara@suse.de>
*/
#ifndef _CIFS_DFS_CACHE_H
#define _CIFS_DFS_CACHE_H
#include <linux/nls.h>
#include <linux/list.h>
#include "cifsglob.h"
struct dfs_cache_tgt_list {
int tl_numtgts;
struct list_head tl_list;
};
struct dfs_cache_tgt_iterator {
char *it_name;
struct list_head it_list;
};
extern int dfs_cache_init(void);
extern void dfs_cache_destroy(void);
extern const struct proc_ops dfscache_proc_ops;
extern int dfs_cache_find(const unsigned int xid, struct cifs_ses *ses,
const struct nls_table *nls_codepage, int remap,
const char *path, struct dfs_info3_param *ref,
struct dfs_cache_tgt_list *tgt_list);
extern int dfs_cache_noreq_find(const char *path, struct dfs_info3_param *ref,
struct dfs_cache_tgt_list *tgt_list);
extern int dfs_cache_update_tgthint(const unsigned int xid,
struct cifs_ses *ses,
const struct nls_table *nls_codepage,
int remap, const char *path,
const struct dfs_cache_tgt_iterator *it);
extern int
dfs_cache_noreq_update_tgthint(const char *path,
const struct dfs_cache_tgt_iterator *it);
extern int dfs_cache_get_tgt_referral(const char *path,
const struct dfs_cache_tgt_iterator *it,
struct dfs_info3_param *ref);
extern int dfs_cache_add_vol(char *mntdata, struct smb_vol *vol,
const char *fullpath);
extern int dfs_cache_update_vol(const char *fullpath,
struct TCP_Server_Info *server);
extern void dfs_cache_del_vol(const char *fullpath);
extern int dfs_cache_get_tgt_share(const struct dfs_cache_tgt_iterator *it,
const char **share, size_t *share_len,
const char **prefix, size_t *prefix_len);
static inline struct dfs_cache_tgt_iterator *
dfs_cache_get_next_tgt(struct dfs_cache_tgt_list *tl,
struct dfs_cache_tgt_iterator *it)
{
if (!tl || list_empty(&tl->tl_list) || !it ||
list_is_last(&it->it_list, &tl->tl_list))
return NULL;
return list_next_entry(it, it_list);
}
static inline struct dfs_cache_tgt_iterator *
dfs_cache_get_tgt_iterator(struct dfs_cache_tgt_list *tl)
{
if (!tl)
return NULL;
return list_first_entry_or_null(&tl->tl_list,
struct dfs_cache_tgt_iterator,
it_list);
}
static inline void dfs_cache_free_tgts(struct dfs_cache_tgt_list *tl)
{
struct dfs_cache_tgt_iterator *it, *nit;
if (!tl || list_empty(&tl->tl_list))
return;
list_for_each_entry_safe(it, nit, &tl->tl_list, it_list) {
list_del(&it->it_list);
kfree(it->it_name);
kfree(it);
}
tl->tl_numtgts = 0;
}
static inline const char *
dfs_cache_get_tgt_name(const struct dfs_cache_tgt_iterator *it)
{
return it ? it->it_name : NULL;
}
static inline int
dfs_cache_get_nr_tgts(const struct dfs_cache_tgt_list *tl)
{
return tl ? tl->tl_numtgts : 0;
}
#endif /* _CIFS_DFS_CACHE_H */