int user_dlm_destroy_lock(struct user_lock_res *lockres)
{
int status = -EBUSY;
struct dlm_ctxt *dlm = dlm_ctxt_from_user_lockres(lockres);
mlog(0, "asked to destroy %.*s\n", lockres->l_namelen, lockres->l_name);
spin_lock(&lockres->l_lock);
if (lockres->l_flags & USER_LOCK_IN_TEARDOWN) {
spin_unlock(&lockres->l_lock);
return 0;
}
lockres->l_flags |= USER_LOCK_IN_TEARDOWN;
while (lockres->l_flags & USER_LOCK_BUSY) {
spin_unlock(&lockres->l_lock);
user_wait_on_busy_lock(lockres);
spin_lock(&lockres->l_lock);
}
if (lockres->l_ro_holders || lockres->l_ex_holders) {
spin_unlock(&lockres->l_lock);
goto bail;
}
status = 0;
if (!(lockres->l_flags & USER_LOCK_ATTACHED)) {
spin_unlock(&lockres->l_lock);
goto bail;
}
lockres->l_flags &= ~USER_LOCK_ATTACHED;
lockres->l_flags |= USER_LOCK_BUSY;
spin_unlock(&lockres->l_lock);
status = dlmunlock(dlm,
&lockres->l_lksb,
LKM_VALBLK,
user_unlock_ast,
lockres);
if (status != DLM_NORMAL) {
user_log_dlm_error("dlmunlock", status, lockres);
status = -EINVAL;
goto bail;
}
user_wait_on_busy_lock(lockres);
status = 0;
bail:
return status;
}
static int o2cb_dlm_unlock(struct ocfs2_cluster_connection *conn,
struct ocfs2_dlm_lksb *lksb,
u32 flags)
{
enum dlm_status status;
int o2dlm_flags = flags_to_o2dlm(flags);
int ret;
status = dlmunlock(conn->cc_lockspace, &lksb->lksb_o2dlm,
o2dlm_flags, o2dlm_unlock_ast_wrapper, lksb);
ret = dlm_status_to_errno(status);
return ret;
}
static void user_dlm_unblock_lock(struct work_struct *work)
{
int new_level, status;
struct user_lock_res *lockres =
container_of(work, struct user_lock_res, l_work);
struct dlm_ctxt *dlm = dlm_ctxt_from_user_lockres(lockres);
mlog(0, "processing lockres %.*s\n", lockres->l_namelen,
lockres->l_name);
spin_lock(&lockres->l_lock);
mlog_bug_on_msg(!(lockres->l_flags & USER_LOCK_QUEUED),
"Lockres %.*s, flags 0x%x\n",
lockres->l_namelen, lockres->l_name, lockres->l_flags);
/* notice that we don't clear USER_LOCK_BLOCKED here. If it's
* set, we want user_ast clear it. */
lockres->l_flags &= ~USER_LOCK_QUEUED;
/* It's valid to get here and no longer be blocked - if we get
* several basts in a row, we might be queued by the first
* one, the unblock thread might run and clear the queued
* flag, and finally we might get another bast which re-queues
* us before our ast for the downconvert is called. */
if (!(lockres->l_flags & USER_LOCK_BLOCKED)) {
spin_unlock(&lockres->l_lock);
goto drop_ref;
}
if (lockres->l_flags & USER_LOCK_IN_TEARDOWN) {
spin_unlock(&lockres->l_lock);
goto drop_ref;
}
if (lockres->l_flags & USER_LOCK_BUSY) {
if (lockres->l_flags & USER_LOCK_IN_CANCEL) {
spin_unlock(&lockres->l_lock);
goto drop_ref;
}
lockres->l_flags |= USER_LOCK_IN_CANCEL;
spin_unlock(&lockres->l_lock);
status = dlmunlock(dlm,
&lockres->l_lksb,
LKM_CANCEL,
user_unlock_ast,
lockres);
if (status != DLM_NORMAL)
user_log_dlm_error("dlmunlock", status, lockres);
goto drop_ref;
}
/* If there are still incompat holders, we can exit safely
* without worrying about re-queueing this lock as that will
* happen on the last call to user_cluster_unlock. */
if ((lockres->l_blocking == LKM_EXMODE)
&& (lockres->l_ex_holders || lockres->l_ro_holders)) {
spin_unlock(&lockres->l_lock);
mlog(0, "can't downconvert for ex: ro = %u, ex = %u\n",
lockres->l_ro_holders, lockres->l_ex_holders);
goto drop_ref;
}
if ((lockres->l_blocking == LKM_PRMODE)
&& lockres->l_ex_holders) {
spin_unlock(&lockres->l_lock);
mlog(0, "can't downconvert for pr: ex = %u\n",
lockres->l_ex_holders);
goto drop_ref;
}
/* yay, we can downconvert now. */
new_level = user_highest_compat_lock_level(lockres->l_blocking);
lockres->l_requested = new_level;
lockres->l_flags |= USER_LOCK_BUSY;
mlog(0, "Downconvert lock from %d to %d\n",
lockres->l_level, new_level);
spin_unlock(&lockres->l_lock);
/* need lock downconvert request now... */
status = dlmlock(dlm,
new_level,
&lockres->l_lksb,
LKM_CONVERT|LKM_VALBLK,
lockres->l_name,
lockres->l_namelen,
user_ast,
lockres,
user_bast);
if (status != DLM_NORMAL) {
user_log_dlm_error("dlmlock", status, lockres);
user_recover_from_dlm_error(lockres);
}
drop_ref:
user_dlm_drop_inode_ref(lockres);
}
