linux/fs/gfs2/locking/dlm/mount.c
Steven Whitehouse 9a776db737 GFS2: Send useful information with uevent messages
In order to distinguish between two differing uevent messages
and to avoid using the (racy) method of reading status from
sysfs in future, this adds some status information to our
uevent messages.

Btw, before anybody says "sysfs isn't racy", I'm aware of that,
but the way that GFS2 was using it (send an ambiugous uevent and
then expect the receiver to read sysfs to find out the status
of the reported operation) was.

The additional benefit of using the new interface is that it
should be possible for a node to recover multiple journals
at the same time, since there is no longer any confusion as
to which journal the status belongs to.

At some future stage, when all the userland programs have been
converted, I intend to remove the old interface.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2009-01-05 07:39:15 +00:00

276 lines
6.3 KiB
C

/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License version 2.
*/
#include "lock_dlm.h"
const struct lm_lockops gdlm_ops;
static struct gdlm_ls *init_gdlm(lm_callback_t cb, struct gfs2_sbd *sdp,
int flags, char *table_name)
{
struct gdlm_ls *ls;
char buf[256], *p;
ls = kzalloc(sizeof(struct gdlm_ls), GFP_KERNEL);
if (!ls)
return NULL;
ls->fscb = cb;
ls->sdp = sdp;
ls->fsflags = flags;
spin_lock_init(&ls->async_lock);
INIT_LIST_HEAD(&ls->delayed);
INIT_LIST_HEAD(&ls->submit);
init_waitqueue_head(&ls->thread_wait);
init_waitqueue_head(&ls->wait_control);
ls->jid = -1;
strncpy(buf, table_name, 256);
buf[255] = '\0';
p = strchr(buf, ':');
if (!p) {
log_info("invalid table_name \"%s\"", table_name);
kfree(ls);
return NULL;
}
*p = '\0';
p++;
strncpy(ls->clustername, buf, GDLM_NAME_LEN);
strncpy(ls->fsname, p, GDLM_NAME_LEN);
return ls;
}
static int make_args(struct gdlm_ls *ls, char *data_arg, int *nodir)
{
char data[256];
char *options, *x, *y;
int error = 0;
memset(data, 0, 256);
strncpy(data, data_arg, 255);
if (!strlen(data)) {
log_error("no mount options, (u)mount helpers not installed");
return -EINVAL;
}
for (options = data; (x = strsep(&options, ":")); ) {
if (!*x)
continue;
y = strchr(x, '=');
if (y)
*y++ = 0;
if (!strcmp(x, "jid")) {
if (!y) {
log_error("need argument to jid");
error = -EINVAL;
break;
}
sscanf(y, "%u", &ls->jid);
} else if (!strcmp(x, "first")) {
if (!y) {
log_error("need argument to first");
error = -EINVAL;
break;
}
sscanf(y, "%u", &ls->first);
} else if (!strcmp(x, "id")) {
if (!y) {
log_error("need argument to id");
error = -EINVAL;
break;
}
sscanf(y, "%u", &ls->id);
} else if (!strcmp(x, "nodir")) {
if (!y) {
log_error("need argument to nodir");
error = -EINVAL;
break;
}
sscanf(y, "%u", nodir);
} else {
log_error("unkonwn option: %s", x);
error = -EINVAL;
break;
}
}
return error;
}
static int gdlm_mount(char *table_name, char *host_data,
lm_callback_t cb, void *cb_data,
unsigned int min_lvb_size, int flags,
struct lm_lockstruct *lockstruct,
struct kobject *fskobj)
{
struct gdlm_ls *ls;
int error = -ENOMEM, nodir = 0;
if (min_lvb_size > GDLM_LVB_SIZE)
goto out;
ls = init_gdlm(cb, cb_data, flags, table_name);
if (!ls)
goto out;
error = make_args(ls, host_data, &nodir);
if (error)
goto out;
error = gdlm_init_threads(ls);
if (error)
goto out_free;
error = gdlm_kobject_setup(ls, fskobj);
if (error)
goto out_thread;
error = dlm_new_lockspace(ls->fsname, strlen(ls->fsname),
&ls->dlm_lockspace,
DLM_LSFL_FS | DLM_LSFL_NEWEXCL |
(nodir ? DLM_LSFL_NODIR : 0),
GDLM_LVB_SIZE);
if (error) {
log_error("dlm_new_lockspace error %d", error);
goto out_kobj;
}
lockstruct->ls_jid = ls->jid;
lockstruct->ls_first = ls->first;
lockstruct->ls_lockspace = ls;
lockstruct->ls_ops = &gdlm_ops;
lockstruct->ls_flags = 0;
lockstruct->ls_lvb_size = GDLM_LVB_SIZE;
return 0;
out_kobj:
gdlm_kobject_release(ls);
out_thread:
gdlm_release_threads(ls);
out_free:
kfree(ls);
out:
return error;
}
static void gdlm_unmount(void *lockspace)
{
struct gdlm_ls *ls = lockspace;
log_debug("unmount flags %lx", ls->flags);
/* FIXME: serialize unmount and withdraw in case they
happen at once. Also, if unmount follows withdraw,
wait for withdraw to finish. */
if (test_bit(DFL_WITHDRAW, &ls->flags))
goto out;
gdlm_kobject_release(ls);
dlm_release_lockspace(ls->dlm_lockspace, 2);
gdlm_release_threads(ls);
BUG_ON(ls->all_locks_count);
out:
kfree(ls);
}
static void gdlm_recovery_done(void *lockspace, unsigned int jid,
unsigned int message)
{
char env_jid[20];
char env_status[20];
char *envp[] = { env_jid, env_status, NULL };
struct gdlm_ls *ls = lockspace;
ls->recover_jid_done = jid;
ls->recover_jid_status = message;
sprintf(env_jid, "JID=%d", jid);
sprintf(env_status, "RECOVERY=%s",
message == LM_RD_SUCCESS ? "Done" : "Failed");
kobject_uevent_env(&ls->kobj, KOBJ_CHANGE, envp);
}
static void gdlm_others_may_mount(void *lockspace)
{
char *message = "FIRSTMOUNT=Done";
char *envp[] = { message, NULL };
struct gdlm_ls *ls = lockspace;
ls->first_done = 1;
kobject_uevent_env(&ls->kobj, KOBJ_CHANGE, envp);
}
/* Userspace gets the offline uevent, blocks new gfs locks on
other mounters, and lets us know (sets WITHDRAW flag). Then,
userspace leaves the mount group while we leave the lockspace. */
static void gdlm_withdraw(void *lockspace)
{
struct gdlm_ls *ls = lockspace;
kobject_uevent(&ls->kobj, KOBJ_OFFLINE);
wait_event_interruptible(ls->wait_control,
test_bit(DFL_WITHDRAW, &ls->flags));
dlm_release_lockspace(ls->dlm_lockspace, 2);
gdlm_release_threads(ls);
gdlm_kobject_release(ls);
}
static int gdlm_plock(void *lockspace, struct lm_lockname *name,
struct file *file, int cmd, struct file_lock *fl)
{
struct gdlm_ls *ls = lockspace;
return dlm_posix_lock(ls->dlm_lockspace, name->ln_number, file, cmd, fl);
}
static int gdlm_punlock(void *lockspace, struct lm_lockname *name,
struct file *file, struct file_lock *fl)
{
struct gdlm_ls *ls = lockspace;
return dlm_posix_unlock(ls->dlm_lockspace, name->ln_number, file, fl);
}
static int gdlm_plock_get(void *lockspace, struct lm_lockname *name,
struct file *file, struct file_lock *fl)
{
struct gdlm_ls *ls = lockspace;
return dlm_posix_get(ls->dlm_lockspace, name->ln_number, file, fl);
}
const struct lm_lockops gdlm_ops = {
.lm_proto_name = "lock_dlm",
.lm_mount = gdlm_mount,
.lm_others_may_mount = gdlm_others_may_mount,
.lm_unmount = gdlm_unmount,
.lm_withdraw = gdlm_withdraw,
.lm_get_lock = gdlm_get_lock,
.lm_put_lock = gdlm_put_lock,
.lm_lock = gdlm_lock,
.lm_unlock = gdlm_unlock,
.lm_plock = gdlm_plock,
.lm_punlock = gdlm_punlock,
.lm_plock_get = gdlm_plock_get,
.lm_cancel = gdlm_cancel,
.lm_hold_lvb = gdlm_hold_lvb,
.lm_unhold_lvb = gdlm_unhold_lvb,
.lm_recovery_done = gdlm_recovery_done,
.lm_owner = THIS_MODULE,
};