+++ /dev/null
-From: David Teigland <teigland@redhat.com>
-commit dc68c7ed362a00a48290252573a8eb9f74463c3a
-Author: David Teigland <teigland@redhat.com>
-Date: Mon Aug 18 11:43:30 2008 -0500
-Subject: dlm: detect available userspace daemon
-
- If dlm_controld (the userspace daemon that controls the setup and
- recovery of the dlm) fails, the kernel should shut down the lockspaces
- in the kernel rather than leaving them running. This is detected by
- having dlm_controld hold a misc device open while running, and if
- the kernel detects a close while the daemon is still needed, it stops
- the lockspaces in the kernel.
-
- Knowing that the userspace daemon isn't running also allows the
- lockspace create/remove routines to avoid waiting on the daemon
- for join/leave operations.
-
-Signed-off-by: David Teigland <teigland@redhat.com>
-Signed-off-by: Coly Li <coly.li@suse.de>
-
-diff --git a/fs/dlm/lockspace.c b/fs/dlm/lockspace.c
-index 56eae4e..ba672fe 100644
---- a/fs/dlm/lockspace.c
-+++ b/fs/dlm/lockspace.c
-@@ -378,6 +378,11 @@ static int new_lockspace(char *name, int namelen, void **lockspace,
- if (!try_module_get(THIS_MODULE))
- return -EINVAL;
-
-+ if (!dlm_user_daemon_available()) {
-+ module_put(THIS_MODULE);
-+ return -EUNATCH;
-+ }
-+
- error = 0;
-
- spin_lock(&lslist_lock);
-@@ -669,7 +674,7 @@ static int release_lockspace(struct dlm_ls *ls, int force)
-
- dlm_device_deregister(ls);
-
-- if (force < 3)
-+ if (force < 3 && dlm_user_daemon_available())
- do_uevent(ls, 0);
-
- dlm_recoverd_stop(ls);
-@@ -791,3 +796,20 @@ int dlm_release_lockspace(void *lockspace, int force)
- return error;
- }
-
-+void dlm_stop_lockspaces(void)
-+{
-+ struct dlm_ls *ls;
-+
-+ restart:
-+ spin_lock(&lslist_lock);
-+ list_for_each_entry(ls, &lslist, ls_list) {
-+ if (!test_bit(LSFL_RUNNING, &ls->ls_flags))
-+ continue;
-+ spin_unlock(&lslist_lock);
-+ log_error(ls, "no userland control daemon, stopping lockspace");
-+ dlm_ls_stop(ls);
-+ goto restart;
-+ }
-+ spin_unlock(&lslist_lock);
-+}
-+
-diff --git a/fs/dlm/lockspace.h b/fs/dlm/lockspace.h
-index 891eabb..f879f87 100644
---- a/fs/dlm/lockspace.h
-+++ b/fs/dlm/lockspace.h
-@@ -20,6 +20,7 @@ struct dlm_ls *dlm_find_lockspace_global(uint32_t id);
- struct dlm_ls *dlm_find_lockspace_local(void *id);
- struct dlm_ls *dlm_find_lockspace_device(int minor);
- void dlm_put_lockspace(struct dlm_ls *ls);
-+void dlm_stop_lockspaces(void);
-
- #endif /* __LOCKSPACE_DOT_H__ */
-
-diff --git a/fs/dlm/user.c b/fs/dlm/user.c
-index 6542110..81627b5 100644
---- a/fs/dlm/user.c
-+++ b/fs/dlm/user.c
-@@ -27,6 +27,8 @@
-
- static const char name_prefix[] = "dlm";
- static const struct file_operations device_fops;
-+static atomic_t dlm_monitor_opened;
-+static int dlm_monitor_unused = 1;
-
- #ifdef CONFIG_COMPAT
-
-@@ -890,6 +892,26 @@ static unsigned int device_poll(struct file *file, poll_table *wait)
- return 0;
- }
-
-+int dlm_user_daemon_available(void)
-+{
-+ /* dlm_controld hasn't started (or, has started, but not
-+ properly populated configfs) */
-+
-+ if (!dlm_our_nodeid())
-+ return 0;
-+
-+ /* This is to deal with versions of dlm_controld that don't
-+ know about the monitor device. We assume that if the
-+ dlm_controld was started (above), but the monitor device
-+ was never opened, that it's an old version. dlm_controld
-+ should open the monitor device before populating configfs. */
-+
-+ if (dlm_monitor_unused)
-+ return 1;
-+
-+ return atomic_read(&dlm_monitor_opened) ? 1 : 0;
-+}
-+
- static int ctl_device_open(struct inode *inode, struct file *file)
- {
- cycle_kernel_lock();
-@@ -902,6 +924,20 @@ static int ctl_device_close(struct inode *inode, struct file *file)
- return 0;
- }
-
-+static int monitor_device_open(struct inode *inode, struct file *file)
-+{
-+ atomic_inc(&dlm_monitor_opened);
-+ dlm_monitor_unused = 0;
-+ return 0;
-+}
-+
-+static int monitor_device_close(struct inode *inode, struct file *file)
-+{
-+ if (atomic_dec_and_test(&dlm_monitor_opened))
-+ dlm_stop_lockspaces();
-+ return 0;
-+}
-+
- static const struct file_operations device_fops = {
- .open = device_open,
- .release = device_close,
-@@ -925,19 +961,42 @@ static struct miscdevice ctl_device = {
- .minor = MISC_DYNAMIC_MINOR,
- };
-
-+static const struct file_operations monitor_device_fops = {
-+ .open = monitor_device_open,
-+ .release = monitor_device_close,
-+ .owner = THIS_MODULE,
-+};
-+
-+static struct miscdevice monitor_device = {
-+ .name = "dlm-monitor",
-+ .fops = &monitor_device_fops,
-+ .minor = MISC_DYNAMIC_MINOR,
-+};
-+
- int __init dlm_user_init(void)
- {
- int error;
-
-+ atomic_set(&dlm_monitor_opened, 0);
-+
- error = misc_register(&ctl_device);
-- if (error)
-+ if (error) {
- log_print("misc_register failed for control device");
-+ goto out;
-+ }
-
-+ error = misc_register(&monitor_device);
-+ if (error) {
-+ log_print("misc_register failed for monitor device");
-+ misc_deregister(&ctl_device);
-+ }
-+ out:
- return error;
- }
-
- void dlm_user_exit(void)
- {
- misc_deregister(&ctl_device);
-+ misc_deregister(&monitor_device);
- }
-
-diff --git a/fs/dlm/user.h b/fs/dlm/user.h
-index c528b6b..35eb6a1 100644
---- a/fs/dlm/user.h
-+++ b/fs/dlm/user.h
-@@ -13,5 +13,6 @@ void dlm_user_add_ast(struct dlm_lkb *lkb, int type);
- int dlm_user_init(void);
- void dlm_user_exit(void);
- int dlm_device_deregister(struct dlm_ls *ls);
-+int dlm_user_daemon_available(void);
-
- #endif
projects / people / pmueller / ipfire-2.x.git / blobdiff