--- /dev/null
+/*
+ * 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 <linux/module.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/fs.h>
+#include <linux/smp_lock.h>
+#include <linux/lm_interface.h>
+
+struct nolock_lockspace {
+ unsigned int nl_lvb_size;
+};
+
+static const struct lm_lockops nolock_ops;
+
+static int nolock_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)
+{
+ char *c;
+ unsigned int jid;
+ struct nolock_lockspace *nl;
+
+ c = strstr(host_data, "jid=");
+ if (!c)
+ jid = 0;
+ else {
+ c += 4;
+ sscanf(c, "%u", &jid);
+ }
+
+ nl = kzalloc(sizeof(struct nolock_lockspace), GFP_KERNEL);
+ if (!nl)
+ return -ENOMEM;
+
+ nl->nl_lvb_size = min_lvb_size;
+
+ lockstruct->ls_jid = jid;
+ lockstruct->ls_first = 1;
+ lockstruct->ls_lvb_size = min_lvb_size;
+ lockstruct->ls_lockspace = nl;
+ lockstruct->ls_ops = &nolock_ops;
+ lockstruct->ls_flags = LM_LSFLAG_LOCAL;
+
+ return 0;
+}
+
+static void nolock_others_may_mount(void *lockspace)
+{
+}
+
+static void nolock_unmount(void *lockspace)
+{
+ struct nolock_lockspace *nl = lockspace;
+ kfree(nl);
+}
+
+static void nolock_withdraw(void *lockspace)
+{
+}
+
+/**
+ * nolock_get_lock - get a lm_lock_t given a descripton of the lock
+ * @lockspace: the lockspace the lock lives in
+ * @name: the name of the lock
+ * @lockp: return the lm_lock_t here
+ *
+ * Returns: 0 on success, -EXXX on failure
+ */
+
+static int nolock_get_lock(void *lockspace, struct lm_lockname *name,
+ void **lockp)
+{
+ *lockp = lockspace;
+ return 0;
+}
+
+/**
+ * nolock_put_lock - get rid of a lock structure
+ * @lock: the lock to throw away
+ *
+ */
+
+static void nolock_put_lock(void *lock)
+{
+}
+
+/**
+ * nolock_lock - acquire a lock
+ * @lock: the lock to manipulate
+ * @cur_state: the current state
+ * @req_state: the requested state
+ * @flags: modifier flags
+ *
+ * Returns: A bitmap of LM_OUT_*
+ */
+
+static unsigned int nolock_lock(void *lock, unsigned int cur_state,
+ unsigned int req_state, unsigned int flags)
+{
+ return req_state | LM_OUT_CACHEABLE;
+}
+
+/**
+ * nolock_unlock - unlock a lock
+ * @lock: the lock to manipulate
+ * @cur_state: the current state
+ *
+ * Returns: 0
+ */
+
+static unsigned int nolock_unlock(void *lock, unsigned int cur_state)
+{
+ return 0;
+}
+
+static void nolock_cancel(void *lock)
+{
+}
+
+/**
+ * nolock_hold_lvb - hold on to a lock value block
+ * @lock: the lock the LVB is associated with
+ * @lvbp: return the lm_lvb_t here
+ *
+ * Returns: 0 on success, -EXXX on failure
+ */
+
+static int nolock_hold_lvb(void *lock, char **lvbp)
+{
+ struct nolock_lockspace *nl = lock;
+ int error = 0;
+
+ *lvbp = kzalloc(nl->nl_lvb_size, GFP_KERNEL);
+ if (!*lvbp)
+ error = -ENOMEM;
+
+ return error;
+}
+
+/**
+ * nolock_unhold_lvb - release a LVB
+ * @lock: the lock the LVB is associated with
+ * @lvb: the lock value block
+ *
+ */
+
+static void nolock_unhold_lvb(void *lock, char *lvb)
+{
+ kfree(lvb);
+}
+
+static int nolock_plock_get(void *lockspace, struct lm_lockname *name,
+ struct file *file, struct file_lock *fl)
+{
+ struct file_lock tmp;
+ int ret;
+
+ ret = posix_test_lock(file, fl, &tmp);
+ fl->fl_type = F_UNLCK;
+ if (ret)
+ memcpy(fl, &tmp, sizeof(struct file_lock));
+
+ return 0;
+}
+
+static int nolock_plock(void *lockspace, struct lm_lockname *name,
+ struct file *file, int cmd, struct file_lock *fl)
+{
+ int error;
+ error = posix_lock_file_wait(file, fl);
+ return error;
+}
+
+static int nolock_punlock(void *lockspace, struct lm_lockname *name,
+ struct file *file, struct file_lock *fl)
+{
+ int error;
+ error = posix_lock_file_wait(file, fl);
+ return error;
+}
+
+static void nolock_recovery_done(void *lockspace, unsigned int jid,
+ unsigned int message)
+{
+}
+
+static const struct lm_lockops nolock_ops = {
+ .lm_proto_name = "lock_nolock",
+ .lm_mount = nolock_mount,
+ .lm_others_may_mount = nolock_others_may_mount,
+ .lm_unmount = nolock_unmount,
+ .lm_withdraw = nolock_withdraw,
+ .lm_get_lock = nolock_get_lock,
+ .lm_put_lock = nolock_put_lock,
+ .lm_lock = nolock_lock,
+ .lm_unlock = nolock_unlock,
+ .lm_cancel = nolock_cancel,
+ .lm_hold_lvb = nolock_hold_lvb,
+ .lm_unhold_lvb = nolock_unhold_lvb,
+ .lm_plock_get = nolock_plock_get,
+ .lm_plock = nolock_plock,
+ .lm_punlock = nolock_punlock,
+ .lm_recovery_done = nolock_recovery_done,
+ .lm_owner = THIS_MODULE,
+};
+
+static int __init init_nolock(void)
+{
+ int error;
+
+ error = gfs2_register_lockproto(&nolock_ops);
+ if (error) {
+ printk(KERN_WARNING
+ "lock_nolock: can't register protocol: %d\n", error);
+ return error;
+ }
+
+ printk(KERN_INFO
+ "Lock_Nolock (built %s %s) installed\n", __DATE__, __TIME__);
+ return 0;
+}
+
+static void __exit exit_nolock(void)
+{
+ gfs2_unregister_lockproto(&nolock_ops);
+}
+
+module_init(init_nolock);
+module_exit(exit_nolock);
+
+MODULE_DESCRIPTION("GFS Nolock Locking Module");
+MODULE_AUTHOR("Red Hat, Inc.");
+MODULE_LICENSE("GPL");
+
git://git.onelab.eu / linux-2.6.git / blobdiff