From 08744015492fec5a30ab8e2779601ae2b1a5e431 Mon Sep 17 00:00:00 2001 From: Paulo Alcantara Date: Wed, 14 Nov 2018 17:24:29 -0200 Subject: cifs: Add support for failover in cifs_reconnect_tcon() After a successful failover, the cifs_reconnect_tcon() function will make sure to reconnect every tcon to new target server. Same as previous commit but for SMB1 codepath. Signed-off-by: Paulo Alcantara Reviewed-by: Aurelien Aptel Signed-off-by: Steve French --- fs/cifs/cifssmb.c | 88 +++++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 85 insertions(+), 3 deletions(-) (limited to 'fs/cifs/cifssmb.c') diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c index f82fd342bca5..b1f49c1c543a 100644 --- a/fs/cifs/cifssmb.c +++ b/fs/cifs/cifssmb.c @@ -44,6 +44,9 @@ #include "cifs_debug.h" #include "fscache.h" #include "smbdirect.h" +#ifdef CONFIG_CIFS_DFS_UPCALL +#include "dfs_cache.h" +#endif #ifdef CONFIG_CIFS_POSIX static struct { @@ -118,6 +121,77 @@ cifs_mark_open_files_invalid(struct cifs_tcon *tcon) */ } +#ifdef CONFIG_CIFS_DFS_UPCALL +static int __cifs_reconnect_tcon(const struct nls_table *nlsc, + struct cifs_tcon *tcon) +{ + int rc; + struct dfs_cache_tgt_list tl; + struct dfs_cache_tgt_iterator *it = NULL; + char tree[MAX_TREE_SIZE + 1]; + const char *tcp_host; + size_t tcp_host_len; + const char *dfs_host; + size_t dfs_host_len; + + if (tcon->ipc) { + snprintf(tree, sizeof(tree), "\\\\%s\\IPC$", + tcon->ses->server->hostname); + return CIFSTCon(0, tcon->ses, tree, tcon, nlsc); + } + + if (!tcon->dfs_path) + return CIFSTCon(0, tcon->ses, tcon->treeName, tcon, nlsc); + + rc = dfs_cache_noreq_find(tcon->dfs_path + 1, NULL, &tl); + if (rc) + return rc; + + extract_unc_hostname(tcon->ses->server->hostname, &tcp_host, + &tcp_host_len); + + for (it = dfs_cache_get_tgt_iterator(&tl); it; + it = dfs_cache_get_next_tgt(&tl, it)) { + const char *tgt = dfs_cache_get_tgt_name(it); + + extract_unc_hostname(tgt, &dfs_host, &dfs_host_len); + + if (dfs_host_len != tcp_host_len + || strncasecmp(dfs_host, tcp_host, dfs_host_len) != 0) { + cifs_dbg(FYI, "%s: skipping %.*s, doesn't match %.*s", + __func__, + (int)dfs_host_len, dfs_host, + (int)tcp_host_len, tcp_host); + continue; + } + + snprintf(tree, sizeof(tree), "\\%s", tgt); + + rc = CIFSTCon(0, tcon->ses, tree, tcon, nlsc); + if (!rc) + break; + if (rc == -EREMOTE) + break; + } + + if (!rc) { + if (it) + rc = dfs_cache_noreq_update_tgthint(tcon->dfs_path + 1, + it); + else + rc = -ENOENT; + } + dfs_cache_free_tgts(&tl); + return rc; +} +#else +static inline int __cifs_reconnect_tcon(const struct nls_table *nlsc, + struct cifs_tcon *tcon) +{ + return CIFSTCon(0, tcon->ses, tcon->treeName, tcon, nlsc); +} +#endif + /* reconnect the socket, tcon, and smb session if needed */ static int cifs_reconnect_tcon(struct cifs_tcon *tcon, int smb_command) @@ -126,6 +200,7 @@ cifs_reconnect_tcon(struct cifs_tcon *tcon, int smb_command) struct cifs_ses *ses; struct TCP_Server_Info *server; struct nls_table *nls_codepage; + int retries; /* * SMBs NegProt, SessSetup, uLogoff do not have tcon yet so check for @@ -152,9 +227,12 @@ cifs_reconnect_tcon(struct cifs_tcon *tcon, int smb_command) } } + retries = server->nr_targets; + /* - * Give demultiplex thread up to 10 seconds to reconnect, should be - * greater than cifs socket timeout which is 7 seconds + * Give demultiplex thread up to 10 seconds to each target available for + * reconnect -- should be greater than cifs socket timeout which is 7 + * seconds. */ while (server->tcpStatus == CifsNeedReconnect) { rc = wait_event_interruptible_timeout(server->response_q, @@ -170,6 +248,9 @@ cifs_reconnect_tcon(struct cifs_tcon *tcon, int smb_command) if (server->tcpStatus != CifsNeedReconnect) break; + if (--retries) + continue; + /* * on "soft" mounts we wait once. Hard mounts keep * retrying until process is killed or server comes @@ -179,6 +260,7 @@ cifs_reconnect_tcon(struct cifs_tcon *tcon, int smb_command) cifs_dbg(FYI, "gave up waiting on reconnect in smb_init\n"); return -EHOSTDOWN; } + retries = server->nr_targets; } if (!ses->need_reconnect && !tcon->need_reconnect) @@ -214,7 +296,7 @@ cifs_reconnect_tcon(struct cifs_tcon *tcon, int smb_command) } cifs_mark_open_files_invalid(tcon); - rc = CIFSTCon(0, ses, tcon->treeName, tcon, nls_codepage); + rc = __cifs_reconnect_tcon(nls_codepage, tcon); mutex_unlock(&ses->session_mutex); cifs_dbg(FYI, "reconnect tcon rc = %d\n", rc); -- cgit v1.2.3