dlm: move plock code from gfs2

Move the code that handles cluster posix locks from gfs2 into the dlm
so that it can be used by both gfs2 and ocfs2.

Signed-off-by: David Teigland <teigland@redhat.com>

5 files changed, 23 insertions, 426 deletions

diff --git a/fs/gfs2/locking/dlm/Makefile b/fs/gfs2/locking/dlm/Makefile
index 89b93b6b..2609bb6 100644
--- a/fs/gfs2/locking/dlm/Makefile
+++ b/fs/gfs2/locking/dlm/Makefile
@@ -1,3 +1,3 @@
 obj-$(CONFIG_GFS2_FS_LOCKING_DLM) += lock_dlm.o
-lock_dlm-y := lock.o main.o mount.o sysfs.o thread.o plock.o
+lock_dlm-y := lock.o main.o mount.o sysfs.o thread.o
 
diff --git a/fs/gfs2/locking/dlm/lock_dlm.h b/fs/gfs2/locking/dlm/lock_dlm.h
index 58fcf8c..a243cf6 100644
--- a/fs/gfs2/locking/dlm/lock_dlm.h
+++ b/fs/gfs2/locking/dlm/lock_dlm.h
@@ -25,6 +25,7 @@
 #include <net/sock.h>
 
 #include <linux/dlm.h>
+#include <linux/dlm_plock.h>
 #include <linux/lm_interface.h>
 
 /*
@@ -173,17 +174,6 @@ void gdlm_cancel(void *);
 int gdlm_hold_lvb(void *, char **);
 void gdlm_unhold_lvb(void *, char *);
 
-/* plock.c */
-
-int gdlm_plock_init(void);
-void gdlm_plock_exit(void);
-int gdlm_plock(void *, struct lm_lockname *, struct file *, int,
-		struct file_lock *);
-int gdlm_plock_get(void *, struct lm_lockname *, struct file *,
-		struct file_lock *);
-int gdlm_punlock(void *, struct lm_lockname *, struct file *,
-		struct file_lock *);
-
 /* mount.c */
 
 extern const struct lm_lockops gdlm_ops;
diff --git a/fs/gfs2/locking/dlm/main.c b/fs/gfs2/locking/dlm/main.c
index 36a2258..b9a03a7 100644
--- a/fs/gfs2/locking/dlm/main.c
+++ b/fs/gfs2/locking/dlm/main.c
@@ -28,13 +28,6 @@ static int __init init_lock_dlm(void)
 		return error;
 	}
 
-	error = gdlm_plock_init();
-	if (error) {
-		gdlm_sysfs_exit();
-		gfs2_unregister_lockproto(&gdlm_ops);
-		return error;
-	}
-
 	printk(KERN_INFO
 	       "Lock_DLM (built %s %s) installed\n", __DATE__, __TIME__);
 	return 0;
@@ -42,7 +35,6 @@ static int __init init_lock_dlm(void)
 
 static void __exit exit_lock_dlm(void)
 {
-	gdlm_plock_exit();
 	gdlm_sysfs_exit();
 	gfs2_unregister_lockproto(&gdlm_ops);
 }
diff --git a/fs/gfs2/locking/dlm/mount.c b/fs/gfs2/locking/dlm/mount.c
index f2efff4..470bdf6 100644
--- a/fs/gfs2/locking/dlm/mount.c
+++ b/fs/gfs2/locking/dlm/mount.c
@@ -236,6 +236,27 @@ static void gdlm_withdraw(void *lockspace)
 	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,
diff --git a/fs/gfs2/locking/dlm/plock.c b/fs/gfs2/locking/dlm/plock.c
deleted file mode 100644
index 2ebd374..0000000
--- a/fs/gfs2/locking/dlm/plock.c
+++ /dev/null
@@ -1,406 +0,0 @@
-/*
- * Copyright (C) 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/miscdevice.h>
-#include <linux/lock_dlm_plock.h>
-#include <linux/poll.h>
-
-#include "lock_dlm.h"
-
-
-static spinlock_t ops_lock;
-static struct list_head send_list;
-static struct list_head recv_list;
-static wait_queue_head_t send_wq;
-static wait_queue_head_t recv_wq;
-
-struct plock_op {
-	struct list_head list;
-	int done;
-	struct gdlm_plock_info info;
-};
-
-struct plock_xop {
-	struct plock_op xop;
-	void *callback;
-	void *fl;
-	void *file;
-	struct file_lock flc;
-};
-
-
-static inline void set_version(struct gdlm_plock_info *info)
-{
-	info->version[0] = GDLM_PLOCK_VERSION_MAJOR;
-	info->version[1] = GDLM_PLOCK_VERSION_MINOR;
-	info->version[2] = GDLM_PLOCK_VERSION_PATCH;
-}
-
-static int check_version(struct gdlm_plock_info *info)
-{
-	if ((GDLM_PLOCK_VERSION_MAJOR != info->version[0]) ||
-	    (GDLM_PLOCK_VERSION_MINOR < info->version[1])) {
-		log_error("plock device version mismatch: "
-			  "kernel (%u.%u.%u), user (%u.%u.%u)",
-			  GDLM_PLOCK_VERSION_MAJOR,
-			  GDLM_PLOCK_VERSION_MINOR,
-			  GDLM_PLOCK_VERSION_PATCH,
-			  info->version[0],
-			  info->version[1],
-			  info->version[2]);
-		return -EINVAL;
-	}
-	return 0;
-}
-
-static void send_op(struct plock_op *op)
-{
-	set_version(&op->info);
-	INIT_LIST_HEAD(&op->list);
-	spin_lock(&ops_lock);
-	list_add_tail(&op->list, &send_list);
-	spin_unlock(&ops_lock);
-	wake_up(&send_wq);
-}
-
-int gdlm_plock(void *lockspace, struct lm_lockname *name,
-	       struct file *file, int cmd, struct file_lock *fl)
-{
-	struct gdlm_ls *ls = lockspace;
-	struct plock_op *op;
-	struct plock_xop *xop;
-	int rv;
-
-	xop = kzalloc(sizeof(*xop), GFP_KERNEL);
-	if (!xop)
-		return -ENOMEM;
-
-	op = &xop->xop;
-	op->info.optype		= GDLM_PLOCK_OP_LOCK;
-	op->info.pid		= fl->fl_pid;
-	op->info.ex		= (fl->fl_type == F_WRLCK);
-	op->info.wait		= IS_SETLKW(cmd);
-	op->info.fsid		= ls->id;
-	op->info.number		= name->ln_number;
-	op->info.start		= fl->fl_start;
-	op->info.end		= fl->fl_end;
-	if (fl->fl_lmops && fl->fl_lmops->fl_grant) {
-		/* fl_owner is lockd which doesn't distinguish
-		   processes on the nfs client */
-		op->info.owner	= (__u64) fl->fl_pid;
-		xop->callback	= fl->fl_lmops->fl_grant;
-		locks_init_lock(&xop->flc);
-		locks_copy_lock(&xop->flc, fl);
-		xop->fl		= fl;
-		xop->file	= file;
-	} else {
-		op->info.owner	= (__u64)(long) fl->fl_owner;
-		xop->callback	= NULL;
-	}
-
-	send_op(op);
-
-	if (xop->callback == NULL)
-		wait_event(recv_wq, (op->done != 0));
-	else
-		return -EINPROGRESS;
-
-	spin_lock(&ops_lock);
-	if (!list_empty(&op->list)) {
-		printk(KERN_INFO "plock op on list\n");
-		list_del(&op->list);
-	}
-	spin_unlock(&ops_lock);
-
-	rv = op->info.rv;
-
-	if (!rv) {
-		if (posix_lock_file_wait(file, fl) < 0)
-			log_error("gdlm_plock: vfs lock error %x,%llx",
-				  name->ln_type,
-				  (unsigned long long)name->ln_number);
-	}
-
-	kfree(xop);
-	return rv;
-}
-
-/* Returns failure iff a succesful lock operation should be canceled */
-static int gdlm_plock_callback(struct plock_op *op)
-{
-	struct file *file;
-	struct file_lock *fl;
-	struct file_lock *flc;
-	int (*notify)(void *, void *, int) = NULL;
-	struct plock_xop *xop = (struct plock_xop *)op;
-	int rv = 0;
-
-	spin_lock(&ops_lock);
-	if (!list_empty(&op->list)) {
-		printk(KERN_INFO "plock op on list\n");
-		list_del(&op->list);
-	}
-	spin_unlock(&ops_lock);
-
-	/* check if the following 2 are still valid or make a copy */
-	file = xop->file;
-	flc = &xop->flc;
-	fl = xop->fl;
-	notify = xop->callback;
-
-	if (op->info.rv) {
-		notify(flc, NULL, op->info.rv);
-		goto out;
-	}
-
-	/* got fs lock; bookkeep locally as well: */
-	flc->fl_flags &= ~FL_SLEEP;
-	if (posix_lock_file(file, flc, NULL)) {
-		/*
-		 * This can only happen in the case of kmalloc() failure.
-		 * The filesystem's own lock is the authoritative lock,
-		 * so a failure to get the lock locally is not a disaster.
-		 * As long as GFS cannot reliably cancel locks (especially
-		 * in a low-memory situation), we're better off ignoring
-		 * this failure than trying to recover.
-		 */
-		log_error("gdlm_plock: vfs lock error file %p fl %p",
-				file, fl);
-	}
-
-	rv = notify(flc, NULL, 0);
-	if (rv) {
-		/* XXX: We need to cancel the fs lock here: */
-		printk("gfs2 lock granted after lock request failed;"
-						" dangling lock!\n");
-		goto out;
-	}
-
-out:
-	kfree(xop);
-	return rv;
-}
-
-int gdlm_punlock(void *lockspace, struct lm_lockname *name,
-		 struct file *file, struct file_lock *fl)
-{
-	struct gdlm_ls *ls = lockspace;
-	struct plock_op *op;
-	int rv;
-
-	op = kzalloc(sizeof(*op), GFP_KERNEL);
-	if (!op)
-		return -ENOMEM;
-
-	if (posix_lock_file_wait(file, fl) < 0)
-		log_error("gdlm_punlock: vfs unlock error %x,%llx",
-			  name->ln_type, (unsigned long long)name->ln_number);
-
-	op->info.optype		= GDLM_PLOCK_OP_UNLOCK;
-	op->info.pid		= fl->fl_pid;
-	op->info.fsid		= ls->id;
-	op->info.number		= name->ln_number;
-	op->info.start		= fl->fl_start;
-	op->info.end		= fl->fl_end;
-	if (fl->fl_lmops && fl->fl_lmops->fl_grant)
-		op->info.owner	= (__u64) fl->fl_pid;
-	else
-		op->info.owner	= (__u64)(long) fl->fl_owner;
-
-	send_op(op);
-	wait_event(recv_wq, (op->done != 0));
-
-	spin_lock(&ops_lock);
-	if (!list_empty(&op->list)) {
-		printk(KERN_INFO "punlock op on list\n");
-		list_del(&op->list);
-	}
-	spin_unlock(&ops_lock);
-
-	rv = op->info.rv;
-
-	if (rv == -ENOENT)
-		rv = 0;
-
-	kfree(op);
-	return rv;
-}
-
-int gdlm_plock_get(void *lockspace, struct lm_lockname *name,
-		   struct file *file, struct file_lock *fl)
-{
-	struct gdlm_ls *ls = lockspace;
-	struct plock_op *op;
-	int rv;
-
-	op = kzalloc(sizeof(*op), GFP_KERNEL);
-	if (!op)
-		return -ENOMEM;
-
-	op->info.optype		= GDLM_PLOCK_OP_GET;
-	op->info.pid		= fl->fl_pid;
-	op->info.ex		= (fl->fl_type == F_WRLCK);
-	op->info.fsid		= ls->id;
-	op->info.number		= name->ln_number;
-	op->info.start		= fl->fl_start;
-	op->info.end		= fl->fl_end;
-	if (fl->fl_lmops && fl->fl_lmops->fl_grant)
-		op->info.owner	= (__u64) fl->fl_pid;
-	else
-		op->info.owner	= (__u64)(long) fl->fl_owner;
-
-	send_op(op);
-	wait_event(recv_wq, (op->done != 0));
-
-	spin_lock(&ops_lock);
-	if (!list_empty(&op->list)) {
-		printk(KERN_INFO "plock_get op on list\n");
-		list_del(&op->list);
-	}
-	spin_unlock(&ops_lock);
-
-	/* info.rv from userspace is 1 for conflict, 0 for no-conflict,
-	   -ENOENT if there are no locks on the file */
-
-	rv = op->info.rv;
-
-	fl->fl_type = F_UNLCK;
-	if (rv == -ENOENT)
-		rv = 0;
-	else if (rv > 0) {
-		fl->fl_type = (op->info.ex) ? F_WRLCK : F_RDLCK;
-		fl->fl_pid = op->info.pid;
-		fl->fl_start = op->info.start;
-		fl->fl_end = op->info.end;
-		rv = 0;
-	}
-
-	kfree(op);
-	return rv;
-}
-
-/* a read copies out one plock request from the send list */
-static ssize_t dev_read(struct file *file, char __user *u, size_t count,
-			loff_t *ppos)
-{
-	struct gdlm_plock_info info;
-	struct plock_op *op = NULL;
-
-	if (count < sizeof(info))
-		return -EINVAL;
-
-	spin_lock(&ops_lock);
-	if (!list_empty(&send_list)) {
-		op = list_entry(send_list.next, struct plock_op, list);
-		list_move(&op->list, &recv_list);
-		memcpy(&info, &op->info, sizeof(info));
-	}
-	spin_unlock(&ops_lock);
-
-	if (!op)
-		return -EAGAIN;
-
-	if (copy_to_user(u, &info, sizeof(info)))
-		return -EFAULT;
-	return sizeof(info);
-}
-
-/* a write copies in one plock result that should match a plock_op
-   on the recv list */
-static ssize_t dev_write(struct file *file, const char __user *u, size_t count,
-			 loff_t *ppos)
-{
-	struct gdlm_plock_info info;
-	struct plock_op *op;
-	int found = 0;
-
-	if (count != sizeof(info))
-		return -EINVAL;
-
-	if (copy_from_user(&info, u, sizeof(info)))
-		return -EFAULT;
-
-	if (check_version(&info))
-		return -EINVAL;
-
-	spin_lock(&ops_lock);
-	list_for_each_entry(op, &recv_list, list) {
-		if (op->info.fsid == info.fsid && op->info.number == info.number &&
-		    op->info.owner == info.owner) {
-			list_del_init(&op->list);
-			found = 1;
-			op->done = 1;
-			memcpy(&op->info, &info, sizeof(info));
-			break;
-		}
-	}
-	spin_unlock(&ops_lock);
-
-	if (found) {
-		struct plock_xop *xop;
-		xop = (struct plock_xop *)op;
-		if (xop->callback)
-			count = gdlm_plock_callback(op);
-		else
-			wake_up(&recv_wq);
-	} else
-		printk(KERN_INFO "gdlm dev_write no op %x %llx\n", info.fsid,
-			(unsigned long long)info.number);
-	return count;
-}
-
-static unsigned int dev_poll(struct file *file, poll_table *wait)
-{
-	unsigned int mask = 0;
-
-	poll_wait(file, &send_wq, wait);
-
-	spin_lock(&ops_lock);
-	if (!list_empty(&send_list))
-		mask = POLLIN | POLLRDNORM;
-	spin_unlock(&ops_lock);
-
-	return mask;
-}
-
-static const struct file_operations dev_fops = {
-	.read    = dev_read,
-	.write   = dev_write,
-	.poll    = dev_poll,
-	.owner   = THIS_MODULE
-};
-
-static struct miscdevice plock_dev_misc = {
-	.minor = MISC_DYNAMIC_MINOR,
-	.name = GDLM_PLOCK_MISC_NAME,
-	.fops = &dev_fops
-};
-
-int gdlm_plock_init(void)
-{
-	int rv;
-
-	spin_lock_init(&ops_lock);
-	INIT_LIST_HEAD(&send_list);
-	INIT_LIST_HEAD(&recv_list);
-	init_waitqueue_head(&send_wq);
-	init_waitqueue_head(&recv_wq);
-
-	rv = misc_register(&plock_dev_misc);
-	if (rv)
-		printk(KERN_INFO "gdlm_plock_init: misc_register failed %d",
-		       rv);
-	return rv;
-}
-
-void gdlm_plock_exit(void)
-{
-	if (misc_deregister(&plock_dev_misc) < 0)
-		printk(KERN_INFO "gdlm_plock_exit: misc_deregister failed");
-}
-