linux/fs/ocfs2/cluster/masklog.c
Mark Fasheh d02f00cc05 ocfs2: allocation reservations
This patch improves Ocfs2 allocation policy by allowing an inode to
reserve a portion of the local alloc bitmap for itself. The reserved
portion (allocation window) is advisory in that other allocation
windows might steal it if the local alloc bitmap becomes
full. Otherwise, the reservations are honored and guaranteed to be
free. When the local alloc window is moved to a different portion of
the bitmap, existing reservations are discarded.

Reservation windows are represented internally by a red-black
tree. Within that tree, each node represents the reservation window of
one inode. An LRU of active reservations is also maintained. When new
data is written, we allocate it from the inodes window. When all bits
in a window are exhausted, we allocate a new one as close to the
previous one as possible. Should we not find free space, an existing
reservation is pulled off the LRU and cannibalized.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2010-05-05 18:17:30 -07:00

173 lines
4.2 KiB
C

/* -*- mode: c; c-basic-offset: 8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* Copyright (C) 2004, 2005 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/string.h>
#include <asm/uaccess.h>
#include "masklog.h"
struct mlog_bits mlog_and_bits = MLOG_BITS_RHS(MLOG_INITIAL_AND_MASK);
EXPORT_SYMBOL_GPL(mlog_and_bits);
struct mlog_bits mlog_not_bits = MLOG_BITS_RHS(MLOG_INITIAL_NOT_MASK);
EXPORT_SYMBOL_GPL(mlog_not_bits);
static ssize_t mlog_mask_show(u64 mask, char *buf)
{
char *state;
if (__mlog_test_u64(mask, mlog_and_bits))
state = "allow";
else if (__mlog_test_u64(mask, mlog_not_bits))
state = "deny";
else
state = "off";
return snprintf(buf, PAGE_SIZE, "%s\n", state);
}
static ssize_t mlog_mask_store(u64 mask, const char *buf, size_t count)
{
if (!strnicmp(buf, "allow", 5)) {
__mlog_set_u64(mask, mlog_and_bits);
__mlog_clear_u64(mask, mlog_not_bits);
} else if (!strnicmp(buf, "deny", 4)) {
__mlog_set_u64(mask, mlog_not_bits);
__mlog_clear_u64(mask, mlog_and_bits);
} else if (!strnicmp(buf, "off", 3)) {
__mlog_clear_u64(mask, mlog_not_bits);
__mlog_clear_u64(mask, mlog_and_bits);
} else
return -EINVAL;
return count;
}
struct mlog_attribute {
struct attribute attr;
u64 mask;
};
#define to_mlog_attr(_attr) container_of(_attr, struct mlog_attribute, attr)
#define define_mask(_name) { \
.attr = { \
.name = #_name, \
.mode = S_IRUGO | S_IWUSR, \
}, \
.mask = ML_##_name, \
}
static struct mlog_attribute mlog_attrs[MLOG_MAX_BITS] = {
define_mask(ENTRY),
define_mask(EXIT),
define_mask(TCP),
define_mask(MSG),
define_mask(SOCKET),
define_mask(HEARTBEAT),
define_mask(HB_BIO),
define_mask(DLMFS),
define_mask(DLM),
define_mask(DLM_DOMAIN),
define_mask(DLM_THREAD),
define_mask(DLM_MASTER),
define_mask(DLM_RECOVERY),
define_mask(AIO),
define_mask(JOURNAL),
define_mask(DISK_ALLOC),
define_mask(SUPER),
define_mask(FILE_IO),
define_mask(EXTENT_MAP),
define_mask(DLM_GLUE),
define_mask(BH_IO),
define_mask(UPTODATE),
define_mask(NAMEI),
define_mask(INODE),
define_mask(VOTE),
define_mask(DCACHE),
define_mask(CONN),
define_mask(QUORUM),
define_mask(EXPORT),
define_mask(XATTR),
define_mask(QUOTA),
define_mask(REFCOUNT),
define_mask(BASTS),
define_mask(ERROR),
define_mask(NOTICE),
define_mask(KTHREAD),
define_mask(RESERVATIONS),
};
static struct attribute *mlog_attr_ptrs[MLOG_MAX_BITS] = {NULL, };
static ssize_t mlog_show(struct kobject *obj, struct attribute *attr,
char *buf)
{
struct mlog_attribute *mlog_attr = to_mlog_attr(attr);
return mlog_mask_show(mlog_attr->mask, buf);
}
static ssize_t mlog_store(struct kobject *obj, struct attribute *attr,
const char *buf, size_t count)
{
struct mlog_attribute *mlog_attr = to_mlog_attr(attr);
return mlog_mask_store(mlog_attr->mask, buf, count);
}
static const struct sysfs_ops mlog_attr_ops = {
.show = mlog_show,
.store = mlog_store,
};
static struct kobj_type mlog_ktype = {
.default_attrs = mlog_attr_ptrs,
.sysfs_ops = &mlog_attr_ops,
};
static struct kset mlog_kset = {
.kobj = {.ktype = &mlog_ktype},
};
int mlog_sys_init(struct kset *o2cb_kset)
{
int i = 0;
while (mlog_attrs[i].attr.mode) {
mlog_attr_ptrs[i] = &mlog_attrs[i].attr;
i++;
}
mlog_attr_ptrs[i] = NULL;
kobject_set_name(&mlog_kset.kobj, "logmask");
mlog_kset.kobj.kset = o2cb_kset;
return kset_register(&mlog_kset);
}
void mlog_sys_shutdown(void)
{
kset_unregister(&mlog_kset);
}