mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-23 04:34:11 +08:00
24c19ef404
OCFS2 puts inode meta data in the "lock value block" provided by the DLM. Typically, i_generation is encoded in the lock name so that a deleted inode on and a new one in the same block don't share the same lvb. Unfortunately, that scheme means that the read in ocfs2_read_locked_inode() is potentially thrown away as soon as the meta data lock is taken - we cannot encode the lock name without first knowing i_generation, which requires a disk read. This patch encodes i_generation in the inode meta data lvb, and removes the value from the inode meta data lock name. This way, the read can be covered by a lock, and at the same time we can distinguish between an up to date and a stale LVB. This will help cold-cache stat(2) performance in particular. Since this patch changes the protocol version, we take the opportunity to do a minor re-organization of two of the LVB fields. Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
130 lines
3.2 KiB
C
130 lines
3.2 KiB
C
/* -*- mode: c; c-basic-offset: 8; -*-
|
|
* vim: noexpandtab sw=8 ts=8 sts=0:
|
|
*
|
|
* sysfile.c
|
|
*
|
|
* Initialize, read, write, etc. system files.
|
|
*
|
|
* Copyright (C) 2002, 2004 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/fs.h>
|
|
#include <linux/types.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/highmem.h>
|
|
|
|
#define MLOG_MASK_PREFIX ML_INODE
|
|
#include <cluster/masklog.h>
|
|
|
|
#include "ocfs2.h"
|
|
|
|
#include "alloc.h"
|
|
#include "dir.h"
|
|
#include "inode.h"
|
|
#include "journal.h"
|
|
#include "sysfile.h"
|
|
|
|
#include "buffer_head_io.h"
|
|
|
|
static struct inode * _ocfs2_get_system_file_inode(struct ocfs2_super *osb,
|
|
int type,
|
|
u32 slot);
|
|
|
|
static inline int is_global_system_inode(int type);
|
|
static inline int is_in_system_inode_array(struct ocfs2_super *osb,
|
|
int type,
|
|
u32 slot);
|
|
|
|
static inline int is_global_system_inode(int type)
|
|
{
|
|
return type >= OCFS2_FIRST_ONLINE_SYSTEM_INODE &&
|
|
type <= OCFS2_LAST_GLOBAL_SYSTEM_INODE;
|
|
}
|
|
|
|
static inline int is_in_system_inode_array(struct ocfs2_super *osb,
|
|
int type,
|
|
u32 slot)
|
|
{
|
|
return slot == osb->slot_num || is_global_system_inode(type);
|
|
}
|
|
|
|
struct inode *ocfs2_get_system_file_inode(struct ocfs2_super *osb,
|
|
int type,
|
|
u32 slot)
|
|
{
|
|
struct inode *inode = NULL;
|
|
struct inode **arr = NULL;
|
|
|
|
/* avoid the lookup if cached in local system file array */
|
|
if (is_in_system_inode_array(osb, type, slot))
|
|
arr = &(osb->system_inodes[type]);
|
|
|
|
if (arr && ((inode = *arr) != NULL)) {
|
|
/* get a ref in addition to the array ref */
|
|
inode = igrab(inode);
|
|
BUG_ON(!inode);
|
|
|
|
return inode;
|
|
}
|
|
|
|
/* this gets one ref thru iget */
|
|
inode = _ocfs2_get_system_file_inode(osb, type, slot);
|
|
|
|
/* add one more if putting into array for first time */
|
|
if (arr && inode) {
|
|
*arr = igrab(inode);
|
|
BUG_ON(!*arr);
|
|
}
|
|
return inode;
|
|
}
|
|
|
|
static struct inode * _ocfs2_get_system_file_inode(struct ocfs2_super *osb,
|
|
int type,
|
|
u32 slot)
|
|
{
|
|
char namebuf[40];
|
|
struct inode *inode = NULL;
|
|
u64 blkno;
|
|
struct buffer_head *dirent_bh = NULL;
|
|
struct ocfs2_dir_entry *de = NULL;
|
|
int status = 0;
|
|
|
|
ocfs2_sprintf_system_inode_name(namebuf,
|
|
sizeof(namebuf),
|
|
type, slot);
|
|
|
|
status = ocfs2_find_files_on_disk(namebuf, strlen(namebuf),
|
|
&blkno, osb->sys_root_inode,
|
|
&dirent_bh, &de);
|
|
if (status < 0) {
|
|
goto bail;
|
|
}
|
|
|
|
inode = ocfs2_iget(osb, blkno, OCFS2_FI_FLAG_SYSFILE);
|
|
if (IS_ERR(inode)) {
|
|
mlog_errno(PTR_ERR(inode));
|
|
inode = NULL;
|
|
goto bail;
|
|
}
|
|
bail:
|
|
if (dirent_bh)
|
|
brelse(dirent_bh);
|
|
return inode;
|
|
}
|
|
|