Skip to content

Commit

Permalink
cifs: get rid of dns resolve worker
Browse files Browse the repository at this point in the history 
We already upcall to resolve hostnames during reconnect by calling
reconn_set_ipaddr_from_hostname(), so there is no point in having a
worker to periodically call it.

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Reviewed-by <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
  • Loading branch information
Paulo Alcantara authored and Steve French committed Feb 20, 2023
1 parent 3e161c2 commit 0e9bd27
Show file tree
Hide file tree
Showing 3 changed files with 6 additions and 53 deletions.
5 changes: 0 additions & 5 deletions fs/cifs/cifsglob.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -77,10 +77,6 @@
#define SMB_ECHO_INTERVAL_MAX 600
#define SMB_ECHO_INTERVAL_DEFAULT 60

/* dns resolution intervals in seconds */
#define SMB_DNS_RESOLVE_INTERVAL_MIN 120
#define SMB_DNS_RESOLVE_INTERVAL_DEFAULT 600

/* smb multichannel query server interfaces interval in seconds */
#define SMB_INTERFACE_POLL_INTERVAL 600

Expand Down Expand Up @@ -691,7 +687,6 @@ struct TCP_Server_Info {
/* point to the SMBD connection if RDMA is used instead of socket */
struct smbd_connection *smbd_conn;
struct delayed_work echo; /* echo ping workqueue job */
struct delayed_work resolve; /* dns resolution workqueue job */
char *smallbuf; /* pointer to current "small" buffer */
char *bigbuf; /* pointer to current "big" buffer */
/* Total size of this PDU. Only valid from cifs_demultiplex_thread */
Expand Down
53 changes: 6 additions & 47 deletions fs/cifs/connect.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -79,8 +79,6 @@ static int reconn_set_ipaddr_from_hostname(struct TCP_Server_Info *server)
int len;
char *unc;
struct sockaddr_storage ss;
time64_t expiry, now;
unsigned long ttl = SMB_DNS_RESOLVE_INTERVAL_DEFAULT;

if (!server->hostname)
return -EINVAL;
Expand All @@ -102,29 +100,19 @@ static int reconn_set_ipaddr_from_hostname(struct TCP_Server_Info *server)
ss = server->dstaddr;
spin_unlock(&server->srv_lock);

rc = dns_resolve_server_name_to_ip(unc, (struct sockaddr *)&ss, &expiry);
rc = dns_resolve_server_name_to_ip(unc, (struct sockaddr *)&ss, NULL);
kfree(unc);

if (rc < 0) {
cifs_dbg(FYI, "%s: failed to resolve server part of %s to IP: %d\n",
__func__, server->hostname, rc);
goto requeue_resolve;
} else {
spin_lock(&server->srv_lock);
memcpy(&server->dstaddr, &ss, sizeof(server->dstaddr));
spin_unlock(&server->srv_lock);
rc = 0;
}

spin_lock(&server->srv_lock);
memcpy(&server->dstaddr, &ss, sizeof(server->dstaddr));
spin_unlock(&server->srv_lock);

now = ktime_get_real_seconds();
if (expiry && expiry > now)
/* To make sure we don't use the cached entry, retry 1s */
ttl = max_t(unsigned long, expiry - now, SMB_DNS_RESOLVE_INTERVAL_MIN) + 1;

requeue_resolve:
cifs_dbg(FYI, "%s: next dns resolution scheduled for %lu seconds in the future\n",
__func__, ttl);
mod_delayed_work(cifsiod_wq, &server->resolve, (ttl * HZ));

return rc;
}

Expand All @@ -148,26 +136,6 @@ static void smb2_query_server_interfaces(struct work_struct *work)
(SMB_INTERFACE_POLL_INTERVAL * HZ));
}

static void cifs_resolve_server(struct work_struct *work)
{
int rc;
struct TCP_Server_Info *server = container_of(work,
struct TCP_Server_Info, resolve.work);

cifs_server_lock(server);

/*
* Resolve the hostname again to make sure that IP address is up-to-date.
*/
rc = reconn_set_ipaddr_from_hostname(server);
if (rc) {
cifs_dbg(FYI, "%s: failed to resolve hostname: %d\n",
__func__, rc);
}

cifs_server_unlock(server);
}

/*
* Update the tcpStatus for the server.
* This is used to signal the cifsd thread to call cifs_reconnect
Expand Down Expand Up @@ -925,7 +893,6 @@ static void clean_demultiplex_info(struct TCP_Server_Info *server)
spin_unlock(&server->srv_lock);

cancel_delayed_work_sync(&server->echo);
cancel_delayed_work_sync(&server->resolve);

spin_lock(&server->srv_lock);
server->tcpStatus = CifsExiting;
Expand Down Expand Up @@ -1549,7 +1516,6 @@ cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
cifs_put_tcp_session(server->primary_server, from_reconnect);

cancel_delayed_work_sync(&server->echo);
cancel_delayed_work_sync(&server->resolve);

if (from_reconnect)
/*
Expand Down Expand Up @@ -1655,7 +1621,6 @@ cifs_get_tcp_session(struct smb3_fs_context *ctx,
INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
INIT_LIST_HEAD(&tcp_ses->smb_ses_list);
INIT_DELAYED_WORK(&tcp_ses->echo, cifs_echo_request);
INIT_DELAYED_WORK(&tcp_ses->resolve, cifs_resolve_server);
INIT_DELAYED_WORK(&tcp_ses->reconnect, smb2_reconnect_server);
mutex_init(&tcp_ses->reconnect_mutex);
#ifdef CONFIG_CIFS_DFS_UPCALL
Expand Down Expand Up @@ -1744,12 +1709,6 @@ cifs_get_tcp_session(struct smb3_fs_context *ctx,
/* queue echo request delayed work */
queue_delayed_work(cifsiod_wq, &tcp_ses->echo, tcp_ses->echo_interval);

/* queue dns resolution delayed work */
cifs_dbg(FYI, "%s: next dns resolution scheduled for %d seconds in the future\n",
__func__, SMB_DNS_RESOLVE_INTERVAL_DEFAULT);

queue_delayed_work(cifsiod_wq, &tcp_ses->resolve, (SMB_DNS_RESOLVE_INTERVAL_DEFAULT * HZ));

return tcp_ses;

out_err_crypto_release:
Expand Down
1 change: 0 additions & 1 deletion fs/cifs/sess.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -480,7 +480,6 @@ cifs_ses_add_channel(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
* remove this channel
*/
cancel_delayed_work_sync(&chan->server->echo);
cancel_delayed_work_sync(&chan->server->resolve);
cancel_delayed_work_sync(&chan->server->reconnect);

spin_lock(&ses->chan_lock);
Expand Down

0 comments on commit 0e9bd27

Please sign in to comment.