[PATCH AUTOSEL 5.12 006/116] fs: dlm: add check if dlm is currently running

From: Sasha Levin
Date: Wed May 05 2021 - 12:31:47 EST


From: Alexander Aring <aahringo@xxxxxxxxxx>

[ Upstream commit 517461630d1c25ee4dfc1dee80973a64189d6ccf ]

This patch adds checks for dlm config attributes regarding to protocol
parameters as it makes only sense to change them when dlm is not running.
It also adds a check for valid protocol specifiers and return invalid
argument if they are not supported.

Signed-off-by: Alexander Aring <aahringo@xxxxxxxxxx>
Signed-off-by: David Teigland <teigland@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/dlm/config.c | 34 ++++++++++++++++++++++++++++++++--
fs/dlm/lowcomms.c | 2 +-
fs/dlm/lowcomms.h | 3 +++
3 files changed, 36 insertions(+), 3 deletions(-)

diff --git a/fs/dlm/config.c b/fs/dlm/config.c
index 8439610c266a..88d95d96e36c 100644
--- a/fs/dlm/config.c
+++ b/fs/dlm/config.c
@@ -164,6 +164,36 @@ static ssize_t cluster_##name##_show(struct config_item *item, char *buf) \
} \
CONFIGFS_ATTR(cluster_, name);

+static int dlm_check_protocol_and_dlm_running(unsigned int x)
+{
+ switch (x) {
+ case 0:
+ /* TCP */
+ break;
+ case 1:
+ /* SCTP */
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (dlm_allow_conn)
+ return -EBUSY;
+
+ return 0;
+}
+
+static int dlm_check_zero_and_dlm_running(unsigned int x)
+{
+ if (!x)
+ return -EINVAL;
+
+ if (dlm_allow_conn)
+ return -EBUSY;
+
+ return 0;
+}
+
static int dlm_check_zero(unsigned int x)
{
if (!x)
@@ -180,7 +210,7 @@ static int dlm_check_buffer_size(unsigned int x)
return 0;
}

-CLUSTER_ATTR(tcp_port, dlm_check_zero);
+CLUSTER_ATTR(tcp_port, dlm_check_zero_and_dlm_running);
CLUSTER_ATTR(buffer_size, dlm_check_buffer_size);
CLUSTER_ATTR(rsbtbl_size, dlm_check_zero);
CLUSTER_ATTR(recover_timer, dlm_check_zero);
@@ -188,7 +218,7 @@ CLUSTER_ATTR(toss_secs, dlm_check_zero);
CLUSTER_ATTR(scan_secs, dlm_check_zero);
CLUSTER_ATTR(log_debug, NULL);
CLUSTER_ATTR(log_info, NULL);
-CLUSTER_ATTR(protocol, NULL);
+CLUSTER_ATTR(protocol, dlm_check_protocol_and_dlm_running);
CLUSTER_ATTR(mark, NULL);
CLUSTER_ATTR(timewarn_cs, dlm_check_zero);
CLUSTER_ATTR(waitwarn_us, NULL);
diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c
index 440dce99d0d9..c438ce0ac115 100644
--- a/fs/dlm/lowcomms.c
+++ b/fs/dlm/lowcomms.c
@@ -135,7 +135,7 @@ static DEFINE_SPINLOCK(dlm_node_addrs_spin);
static struct listen_connection listen_con;
static struct sockaddr_storage *dlm_local_addr[DLM_MAX_ADDR_COUNT];
static int dlm_local_count;
-static int dlm_allow_conn;
+int dlm_allow_conn;

/* Work queues */
static struct workqueue_struct *recv_workqueue;
diff --git a/fs/dlm/lowcomms.h b/fs/dlm/lowcomms.h
index 790d6703b17e..bcd4dbd1dc98 100644
--- a/fs/dlm/lowcomms.h
+++ b/fs/dlm/lowcomms.h
@@ -14,6 +14,9 @@

#define LOWCOMMS_MAX_TX_BUFFER_LEN 4096

+/* switch to check if dlm is running */
+extern int dlm_allow_conn;
+
int dlm_lowcomms_start(void);
void dlm_lowcomms_stop(void);
void dlm_lowcomms_exit(void);
--
2.30.2