6.6-stable review patch. If anyone has any objections, please let me know.
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From: Paulo Alcantara pc@manguebit.com
[ Upstream commit 242d23efc987151ecd34bc0cae4c0b737494fc40 ]
Do not mark tcons for reconnect when current connection matches any of the targets returned by new referral even when there is no cached entry.
Signed-off-by: Paulo Alcantara (Red Hat) pc@manguebit.com Signed-off-by: Steve French stfrench@microsoft.com Stable-dep-of: 74ebd02163fd ("cifs: all initializations for tcon should happen in tcon_info_alloc") Signed-off-by: Sasha Levin sashal@kernel.org --- fs/smb/client/dfs_cache.c | 187 ++++++++++++++++++++++++-------------- 1 file changed, 117 insertions(+), 70 deletions(-)
diff --git a/fs/smb/client/dfs_cache.c b/fs/smb/client/dfs_cache.c index 11c8efecf7aa1..3cf7c88489be4 100644 --- a/fs/smb/client/dfs_cache.c +++ b/fs/smb/client/dfs_cache.c @@ -1095,16 +1095,18 @@ int dfs_cache_get_tgt_share(char *path, const struct dfs_cache_tgt_iterator *it, return 0; }
-static bool target_share_equal(struct TCP_Server_Info *server, const char *s1, const char *s2) +static bool target_share_equal(struct cifs_tcon *tcon, const char *s1) { - char unc[sizeof("\\") + SERVER_NAME_LENGTH] = {0}; + struct TCP_Server_Info *server = tcon->ses->server; + struct sockaddr_storage ss; const char *host; + const char *s2 = &tcon->tree_name[1]; size_t hostlen; - struct sockaddr_storage ss; + char unc[sizeof("\\") + SERVER_NAME_LENGTH] = {0}; bool match; int rc;
- if (strcasecmp(s1, s2)) + if (strcasecmp(s2, s1)) return false;
/* @@ -1128,34 +1130,6 @@ static bool target_share_equal(struct TCP_Server_Info *server, const char *s1, c return match; }
-/* - * Mark dfs tcon for reconnecting when the currently connected tcon does not match any of the new - * target shares in @refs. - */ -static void mark_for_reconnect_if_needed(struct TCP_Server_Info *server, - const char *path, - struct dfs_cache_tgt_list *old_tl, - struct dfs_cache_tgt_list *new_tl) -{ - struct dfs_cache_tgt_iterator *oit, *nit; - - for (oit = dfs_cache_get_tgt_iterator(old_tl); oit; - oit = dfs_cache_get_next_tgt(old_tl, oit)) { - for (nit = dfs_cache_get_tgt_iterator(new_tl); nit; - nit = dfs_cache_get_next_tgt(new_tl, nit)) { - if (target_share_equal(server, - dfs_cache_get_tgt_name(oit), - dfs_cache_get_tgt_name(nit))) { - dfs_cache_noreq_update_tgthint(path, nit); - return; - } - } - } - - cifs_dbg(FYI, "%s: no cached or matched targets. mark dfs share for reconnect.\n", __func__); - cifs_signal_cifsd_for_reconnect(server, true); -} - static bool is_ses_good(struct cifs_ses *ses) { struct TCP_Server_Info *server = ses->server; @@ -1172,41 +1146,35 @@ static bool is_ses_good(struct cifs_ses *ses) return ret; }
-/* Refresh dfs referral of @ses and mark it for reconnect if needed */ -static void __refresh_ses_referral(struct cifs_ses *ses, bool force_refresh) +static char *get_ses_refpath(struct cifs_ses *ses) { struct TCP_Server_Info *server = ses->server; - DFS_CACHE_TGT_LIST(old_tl); - DFS_CACHE_TGT_LIST(new_tl); - bool needs_refresh = false; - struct cache_entry *ce; - unsigned int xid; - char *path = NULL; - int rc = 0; - - xid = get_xid(); + char *path = ERR_PTR(-ENOENT);
mutex_lock(&server->refpath_lock); if (server->leaf_fullpath) { path = kstrdup(server->leaf_fullpath + 1, GFP_ATOMIC); if (!path) - rc = -ENOMEM; + path = ERR_PTR(-ENOMEM); } mutex_unlock(&server->refpath_lock); - if (!path) - goto out; + return path; +}
- down_read(&htable_rw_lock); - ce = lookup_cache_entry(path); - needs_refresh = force_refresh || IS_ERR(ce) || cache_entry_expired(ce); - if (!IS_ERR(ce)) { - rc = get_targets(ce, &old_tl); - cifs_dbg(FYI, "%s: get_targets: %d\n", __func__, rc); - } - up_read(&htable_rw_lock); +/* Refresh dfs referral of @ses */ +static void refresh_ses_referral(struct cifs_ses *ses) +{ + struct cache_entry *ce; + unsigned int xid; + char *path; + int rc = 0;
- if (!needs_refresh) { - rc = 0; + xid = get_xid(); + + path = get_ses_refpath(ses); + if (IS_ERR(path)) { + rc = PTR_ERR(path); + path = NULL; goto out; }
@@ -1217,29 +1185,106 @@ static void __refresh_ses_referral(struct cifs_ses *ses, bool force_refresh) goto out; }
- ce = cache_refresh_path(xid, ses, path, true); - if (!IS_ERR(ce)) { - rc = get_targets(ce, &new_tl); + ce = cache_refresh_path(xid, ses, path, false); + if (!IS_ERR(ce)) up_read(&htable_rw_lock); - cifs_dbg(FYI, "%s: get_targets: %d\n", __func__, rc); - mark_for_reconnect_if_needed(server, path, &old_tl, &new_tl); - } + else + rc = PTR_ERR(ce);
out: free_xid(xid); - dfs_cache_free_tgts(&old_tl); - dfs_cache_free_tgts(&new_tl); kfree(path); }
-static inline void refresh_ses_referral(struct cifs_ses *ses) +static int __refresh_tcon_referral(struct cifs_tcon *tcon, + const char *path, + struct dfs_info3_param *refs, + int numrefs, bool force_refresh) { - __refresh_ses_referral(ses, false); + struct cache_entry *ce; + bool reconnect = force_refresh; + int rc = 0; + int i; + + if (unlikely(!numrefs)) + return 0; + + if (force_refresh) { + for (i = 0; i < numrefs; i++) { + /* TODO: include prefix paths in the matching */ + if (target_share_equal(tcon, refs[i].node_name)) { + reconnect = false; + break; + } + } + } + + down_write(&htable_rw_lock); + ce = lookup_cache_entry(path); + if (!IS_ERR(ce)) { + if (force_refresh || cache_entry_expired(ce)) + rc = update_cache_entry_locked(ce, refs, numrefs); + } else if (PTR_ERR(ce) == -ENOENT) { + ce = add_cache_entry_locked(refs, numrefs); + } + up_write(&htable_rw_lock); + + if (IS_ERR(ce)) + rc = PTR_ERR(ce); + if (reconnect) { + cifs_tcon_dbg(FYI, "%s: mark for reconnect\n", __func__); + cifs_signal_cifsd_for_reconnect(tcon->ses->server, true); + } + return rc; }
-static inline void force_refresh_ses_referral(struct cifs_ses *ses) +static void refresh_tcon_referral(struct cifs_tcon *tcon, bool force_refresh) { - __refresh_ses_referral(ses, true); + struct dfs_info3_param *refs = NULL; + struct cache_entry *ce; + struct cifs_ses *ses; + unsigned int xid; + bool needs_refresh; + char *path; + int numrefs = 0; + int rc = 0; + + xid = get_xid(); + ses = tcon->ses; + + path = get_ses_refpath(ses); + if (IS_ERR(path)) { + rc = PTR_ERR(path); + path = NULL; + goto out; + } + + down_read(&htable_rw_lock); + ce = lookup_cache_entry(path); + needs_refresh = force_refresh || IS_ERR(ce) || cache_entry_expired(ce); + if (!needs_refresh) { + up_read(&htable_rw_lock); + goto out; + } + up_read(&htable_rw_lock); + + ses = CIFS_DFS_ROOT_SES(ses); + if (!is_ses_good(ses)) { + cifs_dbg(FYI, "%s: skip cache refresh due to disconnected ipc\n", + __func__); + goto out; + } + + rc = get_dfs_referral(xid, ses, path, &refs, &numrefs); + if (!rc) { + rc = __refresh_tcon_referral(tcon, path, refs, + numrefs, force_refresh); + } + +out: + free_xid(xid); + kfree(path); + free_dfs_info_array(refs, numrefs); }
/** @@ -1280,7 +1325,7 @@ int dfs_cache_remount_fs(struct cifs_sb_info *cifs_sb) */ cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
- force_refresh_ses_referral(tcon->ses); + refresh_tcon_referral(tcon, true); return 0; }
@@ -1291,9 +1336,11 @@ void dfs_cache_refresh(struct work_struct *work) struct cifs_ses *ses;
tcon = container_of(work, struct cifs_tcon, dfs_cache_work.work); + ses = tcon->ses->dfs_root_ses;
- for (ses = tcon->ses; ses; ses = ses->dfs_root_ses) + for (; ses; ses = ses->dfs_root_ses) refresh_ses_referral(ses); + refresh_tcon_referral(tcon, false);
queue_delayed_work(dfscache_wq, &tcon->dfs_cache_work, atomic_read(&dfs_cache_ttl) * HZ);