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| author |   Paulo Alcantara <pc@cjr.nz> | 2021-11-04 13:13:28 -0300 |
|---|---|---|
| committer |   Steve French <stfrench@microsoft.com> | 2021-11-09 23:03:08 -0600 |
| commit | 4ac0536f8874a903a72bddc57eb88db774261e3a (patch) | |
| tree | e596ccf5a96d47d4a35a4b097f8f4140ca8112ca /fs/cifs | |
| parent | cifs: split out dfs code from cifs_reconnect() (diff) | |
| download | linux-dev-4ac0536f8874a903a72bddc57eb88db774261e3a.tar.xz linux-dev-4ac0536f8874a903a72bddc57eb88db774261e3a.zip | |
cifs: set a minimum of 120s for next dns resolution
With commit 506c1da44fee ("cifs: use the expiry output of dns_query to
schedule next resolution") and after triggering the first reconnect,
the next async dns resolution of tcp server's hostname would be
scheduled based on dns_resolver's key expiry default, which happens to
default to 5s on most systems that use key.dns_resolver for upcall.
As per key.dns_resolver.conf(5):
default_ttl=<number>
The number of seconds to set as the expiration on a cached
record. This will be overridden if the program manages to re-
trieve TTL information along with the addresses (if, for exam-
ple, it accesses the DNS directly). The default is 5 seconds.
The value must be in the range 1 to INT_MAX.
Make the next async dns resolution no shorter than 120s as we do not
want to be upcalling too often.
Cc: stable@vger.kernel.org
Fixes: 506c1da44fee ("cifs: use the expiry output of dns_query to schedule next resolution")
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Diffstat (limited to 'fs/cifs')
| -rw-r--r-- | fs/cifs/cifsglob.h | 3 | ||||
| -rw-r--r-- | fs/cifs/connect.c | 2 |
2 files changed, 3 insertions, 2 deletions
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index 41e97df4e0e5..102a4a2b734d 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -76,7 +76,8 @@ #define SMB_ECHO_INTERVAL_MAX 600 #define SMB_ECHO_INTERVAL_DEFAULT 60 -/* dns resolution interval in seconds */ +/* dns resolution intervals in seconds */ +#define SMB_DNS_RESOLVE_INTERVAL_MIN 120 #define SMB_DNS_RESOLVE_INTERVAL_DEFAULT 600 /* maximum number of PDUs in one compound */ diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index f5c5731cda02..6278a90cb027 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -115,7 +115,7 @@ static int reconn_set_ipaddr_from_hostname(struct TCP_Server_Info *server) * To make sure we don't use the cached entry, retry 1s * after expiry. */ - ttl = (expiry - now + 1); + ttl = max_t(unsigned long, expiry - now, SMB_DNS_RESOLVE_INTERVAL_MIN) + 1; } rc = !rc ? -1 : 0; |