[DLM] The core of the DLM for GFS2/CLVM

This is the core of the distributed lock manager which is required
to use GFS2 as a cluster filesystem. It is also used by CLVM and
can be used as a standalone lock manager independantly of either
of these two projects.

It implements VAX-style locking modes.

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

fs/dlm/memory.c

@@ -0,0 +1,122 @@
+/******************************************************************************
+*******************************************************************************
+**
+**  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 v.2.
+**
+*******************************************************************************
+******************************************************************************/
+
+#include "dlm_internal.h"
+#include "config.h"
+#include "memory.h"
+
+static kmem_cache_t *lkb_cache;
+
+
+int dlm_memory_init(void)
+{
+	int ret = 0;
+
+	lkb_cache = kmem_cache_create("dlm_lkb", sizeof(struct dlm_lkb),
+				__alignof__(struct dlm_lkb), 0, NULL, NULL);
+	if (!lkb_cache)
+		ret = -ENOMEM;
+	return ret;
+}
+
+void dlm_memory_exit(void)
+{
+	if (lkb_cache)
+		kmem_cache_destroy(lkb_cache);
+}
+
+char *allocate_lvb(struct dlm_ls *ls)
+{
+	char *p;
+
+	p = kmalloc(ls->ls_lvblen, GFP_KERNEL);
+	if (p)
+		memset(p, 0, ls->ls_lvblen);
+	return p;
+}
+
+void free_lvb(char *p)
+{
+	kfree(p);
+}
+
+uint64_t *allocate_range(struct dlm_ls *ls)
+{
+	int ralen = 4*sizeof(uint64_t);
+	uint64_t *p;
+
+	p = kmalloc(ralen, GFP_KERNEL);
+	if (p)
+		memset(p, 0, ralen);
+	return p;
+}
+
+void free_range(uint64_t *p)
+{
+	kfree(p);
+}
+
+/* FIXME: have some minimal space built-in to rsb for the name and
+   kmalloc a separate name if needed, like dentries are done */
+
+struct dlm_rsb *allocate_rsb(struct dlm_ls *ls, int namelen)
+{
+	struct dlm_rsb *r;
+
+	DLM_ASSERT(namelen <= DLM_RESNAME_MAXLEN,);
+
+	r = kmalloc(sizeof(*r) + namelen, GFP_KERNEL);
+	if (r)
+		memset(r, 0, sizeof(*r) + namelen);
+	return r;
+}
+
+void free_rsb(struct dlm_rsb *r)
+{
+	if (r->res_lvbptr)
+		free_lvb(r->res_lvbptr);
+	kfree(r);
+}
+
+struct dlm_lkb *allocate_lkb(struct dlm_ls *ls)
+{
+	struct dlm_lkb *lkb;
+
+	lkb = kmem_cache_alloc(lkb_cache, GFP_KERNEL);
+	if (lkb)
+		memset(lkb, 0, sizeof(*lkb));
+	return lkb;
+}
+
+void free_lkb(struct dlm_lkb *lkb)
+{
+	kmem_cache_free(lkb_cache, lkb);
+}
+
+struct dlm_direntry *allocate_direntry(struct dlm_ls *ls, int namelen)
+{
+	struct dlm_direntry *de;
+
+	DLM_ASSERT(namelen <= DLM_RESNAME_MAXLEN,);
+
+	de = kmalloc(sizeof(*de) + namelen, GFP_KERNEL);
+	if (de)
+		memset(de, 0, sizeof(*de) + namelen);
+	return de;
+}
+
+void free_direntry(struct dlm_direntry *de)
+{
+	kfree(de);
+}
+