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DEFINITIONS
This source file includes following definitions.
- ocfs2_invalidate_slot
- ocfs2_set_slot
- ocfs2_update_slot_info_extended
- ocfs2_update_slot_info_old
- ocfs2_update_slot_info
- ocfs2_refresh_slot_info
- ocfs2_update_disk_slot_extended
- ocfs2_update_disk_slot_old
- ocfs2_update_disk_slot
- ocfs2_slot_map_physical_size
- __ocfs2_node_num_to_slot
- __ocfs2_find_empty_slot
- ocfs2_node_num_to_slot
- ocfs2_slot_to_node_num_locked
- __ocfs2_free_slot_info
- ocfs2_clear_slot
- ocfs2_map_slot_buffers
- ocfs2_init_slot_info
- ocfs2_free_slot_info
- ocfs2_find_slot
- ocfs2_put_slot
/* -*- mode: c; c-basic-offset: 8; -*-
* vim: noexpandtab sw=8 ts=8 sts=0:
*
* slot_map.c
*
*
*
* 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/types.h>
#include <linux/slab.h>
#include <linux/highmem.h>
#define MLOG_MASK_PREFIX ML_SUPER
#include <cluster/masklog.h>
#include "ocfs2.h"
#include "dlmglue.h"
#include "extent_map.h"
#include "heartbeat.h"
#include "inode.h"
#include "slot_map.h"
#include "super.h"
#include "sysfile.h"
#include "buffer_head_io.h"
struct ocfs2_slot {
int sl_valid;
unsigned int sl_node_num;
};
struct ocfs2_slot_info {
int si_extended;
int si_slots_per_block;
struct inode *si_inode;
unsigned int si_blocks;
struct buffer_head **si_bh;
unsigned int si_num_slots;
struct ocfs2_slot *si_slots;
};
static int __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si,
unsigned int node_num);
static void ocfs2_invalidate_slot(struct ocfs2_slot_info *si,
int slot_num)
{
BUG_ON((slot_num < 0) || (slot_num >= si->si_num_slots));
si->si_slots[slot_num].sl_valid = 0;
}
static void ocfs2_set_slot(struct ocfs2_slot_info *si,
int slot_num, unsigned int node_num)
{
BUG_ON((slot_num < 0) || (slot_num >= si->si_num_slots));
si->si_slots[slot_num].sl_valid = 1;
si->si_slots[slot_num].sl_node_num = node_num;
}
/* This version is for the extended slot map */
static void ocfs2_update_slot_info_extended(struct ocfs2_slot_info *si)
{
int b, i, slotno;
struct ocfs2_slot_map_extended *se;
slotno = 0;
for (b = 0; b < si->si_blocks; b++) {
se = (struct ocfs2_slot_map_extended *)si->si_bh[b]->b_data;
for (i = 0;
(i < si->si_slots_per_block) &&
(slotno < si->si_num_slots);
i++, slotno++) {
if (se->se_slots[i].es_valid)
ocfs2_set_slot(si, slotno,
le32_to_cpu(se->se_slots[i].es_node_num));
else
ocfs2_invalidate_slot(si, slotno);
}
}
}
/*
* Post the slot information on disk into our slot_info struct.
* Must be protected by osb_lock.
*/
static void ocfs2_update_slot_info_old(struct ocfs2_slot_info *si)
{
int i;
struct ocfs2_slot_map *sm;
sm = (struct ocfs2_slot_map *)si->si_bh[0]->b_data;
for (i = 0; i < si->si_num_slots; i++) {
if (le16_to_cpu(sm->sm_slots[i]) == (u16)OCFS2_INVALID_SLOT)
ocfs2_invalidate_slot(si, i);
else
ocfs2_set_slot(si, i, le16_to_cpu(sm->sm_slots[i]));
}
}
static void ocfs2_update_slot_info(struct ocfs2_slot_info *si)
{
/*
* The slot data will have been refreshed when ocfs2_super_lock
* was taken.
*/
if (si->si_extended)
ocfs2_update_slot_info_extended(si);
else
ocfs2_update_slot_info_old(si);
}
int ocfs2_refresh_slot_info(struct ocfs2_super *osb)
{
int ret;
struct ocfs2_slot_info *si = osb->slot_info;
if (si == NULL)
return 0;
BUG_ON(si->si_blocks == 0);
BUG_ON(si->si_bh == NULL);
mlog(0, "Refreshing slot map, reading %u block(s)\n",
si->si_blocks);
/*
* We pass -1 as blocknr because we expect all of si->si_bh to
* be !NULL. Thus, ocfs2_read_blocks() will ignore blocknr. If
* this is not true, the read of -1 (UINT64_MAX) will fail.
*/
ret = ocfs2_read_blocks(si->si_inode, -1, si->si_blocks, si->si_bh,
OCFS2_BH_IGNORE_CACHE);
if (ret == 0) {
spin_lock(&osb->osb_lock);
ocfs2_update_slot_info(si);
spin_unlock(&osb->osb_lock);
}
return ret;
}
/* post the our slot info stuff into it's destination bh and write it
* out. */
static void ocfs2_update_disk_slot_extended(struct ocfs2_slot_info *si,
int slot_num,
struct buffer_head **bh)
{
int blkind = slot_num / si->si_slots_per_block;
int slotno = slot_num % si->si_slots_per_block;
struct ocfs2_slot_map_extended *se;
BUG_ON(blkind >= si->si_blocks);
se = (struct ocfs2_slot_map_extended *)si->si_bh[blkind]->b_data;
se->se_slots[slotno].es_valid = si->si_slots[slot_num].sl_valid;
if (si->si_slots[slot_num].sl_valid)
se->se_slots[slotno].es_node_num =
cpu_to_le32(si->si_slots[slot_num].sl_node_num);
*bh = si->si_bh[blkind];
}
static void ocfs2_update_disk_slot_old(struct ocfs2_slot_info *si,
int slot_num,
struct buffer_head **bh)
{
int i;
struct ocfs2_slot_map *sm;
sm = (struct ocfs2_slot_map *)si->si_bh[0]->b_data;
for (i = 0; i < si->si_num_slots; i++) {
if (si->si_slots[i].sl_valid)
sm->sm_slots[i] =
cpu_to_le16(si->si_slots[i].sl_node_num);
else
sm->sm_slots[i] = cpu_to_le16(OCFS2_INVALID_SLOT);
}
*bh = si->si_bh[0];
}
static int ocfs2_update_disk_slot(struct ocfs2_super *osb,
struct ocfs2_slot_info *si,
int slot_num)
{
int status;
struct buffer_head *bh;
spin_lock(&osb->osb_lock);
if (si->si_extended)
ocfs2_update_disk_slot_extended(si, slot_num, &bh);
else
ocfs2_update_disk_slot_old(si, slot_num, &bh);
spin_unlock(&osb->osb_lock);
status = ocfs2_write_block(osb, bh, si->si_inode);
if (status < 0)
mlog_errno(status);
return status;
}
/*
* Calculate how many bytes are needed by the slot map. Returns
* an error if the slot map file is too small.
*/
static int ocfs2_slot_map_physical_size(struct ocfs2_super *osb,
struct inode *inode,
unsigned long long *bytes)
{
unsigned long long bytes_needed;
if (ocfs2_uses_extended_slot_map(osb)) {
bytes_needed = osb->max_slots *
sizeof(struct ocfs2_extended_slot);
} else {
bytes_needed = osb->max_slots * sizeof(__le16);
}
if (bytes_needed > i_size_read(inode)) {
mlog(ML_ERROR,
"Slot map file is too small! (size %llu, needed %llu)\n",
i_size_read(inode), bytes_needed);
return -ENOSPC;
}
*bytes = bytes_needed;
return 0;
}
/* try to find global node in the slot info. Returns -ENOENT
* if nothing is found. */
static int __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si,
unsigned int node_num)
{
int i, ret = -ENOENT;
for(i = 0; i < si->si_num_slots; i++) {
if (si->si_slots[i].sl_valid &&
(node_num == si->si_slots[i].sl_node_num)) {
ret = i;
break;
}
}
return ret;
}
static int __ocfs2_find_empty_slot(struct ocfs2_slot_info *si,
int preferred)
{
int i, ret = -ENOSPC;
if ((preferred >= 0) && (preferred < si->si_num_slots)) {
if (!si->si_slots[preferred].sl_valid) {
ret = preferred;
goto out;
}
}
for(i = 0; i < si->si_num_slots; i++) {
if (!si->si_slots[i].sl_valid) {
ret = i;
break;
}
}
out:
return ret;
}
int ocfs2_node_num_to_slot(struct ocfs2_super *osb, unsigned int node_num)
{
int slot;
struct ocfs2_slot_info *si = osb->slot_info;
spin_lock(&osb->osb_lock);
slot = __ocfs2_node_num_to_slot(si, node_num);
spin_unlock(&osb->osb_lock);
return slot;
}
int ocfs2_slot_to_node_num_locked(struct ocfs2_super *osb, int slot_num,
unsigned int *node_num)
{
struct ocfs2_slot_info *si = osb->slot_info;
assert_spin_locked(&osb->osb_lock);
BUG_ON(slot_num < 0);
BUG_ON(slot_num > osb->max_slots);
if (!si->si_slots[slot_num].sl_valid)
return -ENOENT;
*node_num = si->si_slots[slot_num].sl_node_num;
return 0;
}
static void __ocfs2_free_slot_info(struct ocfs2_slot_info *si)
{
unsigned int i;
if (si == NULL)
return;
if (si->si_inode)
iput(si->si_inode);
if (si->si_bh) {
for (i = 0; i < si->si_blocks; i++) {
if (si->si_bh[i]) {
brelse(si->si_bh[i]);
si->si_bh[i] = NULL;
}
}
kfree(si->si_bh);
}
kfree(si);
}
int ocfs2_clear_slot(struct ocfs2_super *osb, int slot_num)
{
struct ocfs2_slot_info *si = osb->slot_info;
if (si == NULL)
return 0;
spin_lock(&osb->osb_lock);
ocfs2_invalidate_slot(si, slot_num);
spin_unlock(&osb->osb_lock);
return ocfs2_update_disk_slot(osb, osb->slot_info, slot_num);
}
static int ocfs2_map_slot_buffers(struct ocfs2_super *osb,
struct ocfs2_slot_info *si)
{
int status = 0;
u64 blkno;
unsigned long long blocks, bytes;
unsigned int i;
struct buffer_head *bh;
status = ocfs2_slot_map_physical_size(osb, si->si_inode, &bytes);
if (status)
goto bail;
blocks = ocfs2_blocks_for_bytes(si->si_inode->i_sb, bytes);
BUG_ON(blocks > UINT_MAX);
si->si_blocks = blocks;
if (!si->si_blocks)
goto bail;
if (si->si_extended)
si->si_slots_per_block =
(osb->sb->s_blocksize /
sizeof(struct ocfs2_extended_slot));
else
si->si_slots_per_block = osb->sb->s_blocksize / sizeof(__le16);
/* The size checks above should ensure this */
BUG_ON((osb->max_slots / si->si_slots_per_block) > blocks);
mlog(0, "Slot map needs %u buffers for %llu bytes\n",
si->si_blocks, bytes);
si->si_bh = kzalloc(sizeof(struct buffer_head *) * si->si_blocks,
GFP_KERNEL);
if (!si->si_bh) {
status = -ENOMEM;
mlog_errno(status);
goto bail;
}
for (i = 0; i < si->si_blocks; i++) {
status = ocfs2_extent_map_get_blocks(si->si_inode, i,
&blkno, NULL, NULL);
if (status < 0) {
mlog_errno(status);
goto bail;
}
mlog(0, "Reading slot map block %u at %llu\n", i,
(unsigned long long)blkno);
bh = NULL; /* Acquire a fresh bh */
status = ocfs2_read_blocks(si->si_inode, blkno, 1, &bh,
OCFS2_BH_IGNORE_CACHE);
if (status < 0) {
mlog_errno(status);
goto bail;
}
si->si_bh[i] = bh;
}
bail:
return status;
}
int ocfs2_init_slot_info(struct ocfs2_super *osb)
{
int status;
struct inode *inode = NULL;
struct ocfs2_slot_info *si;
si = kzalloc(sizeof(struct ocfs2_slot_info) +
(sizeof(struct ocfs2_slot) * osb->max_slots),
GFP_KERNEL);
if (!si) {
status = -ENOMEM;
mlog_errno(status);
goto bail;
}
si->si_extended = ocfs2_uses_extended_slot_map(osb);
si->si_num_slots = osb->max_slots;
si->si_slots = (struct ocfs2_slot *)((char *)si +
sizeof(struct ocfs2_slot_info));
inode = ocfs2_get_system_file_inode(osb, SLOT_MAP_SYSTEM_INODE,
OCFS2_INVALID_SLOT);
if (!inode) {
status = -EINVAL;
mlog_errno(status);
goto bail;
}
si->si_inode = inode;
status = ocfs2_map_slot_buffers(osb, si);
if (status < 0) {
mlog_errno(status);
goto bail;
}
osb->slot_info = (struct ocfs2_slot_info *)si;
bail:
if (status < 0 && si)
__ocfs2_free_slot_info(si);
return status;
}
void ocfs2_free_slot_info(struct ocfs2_super *osb)
{
struct ocfs2_slot_info *si = osb->slot_info;
osb->slot_info = NULL;
__ocfs2_free_slot_info(si);
}
int ocfs2_find_slot(struct ocfs2_super *osb)
{
int status;
int slot;
struct ocfs2_slot_info *si;
mlog_entry_void();
si = osb->slot_info;
spin_lock(&osb->osb_lock);
ocfs2_update_slot_info(si);
/* search for ourselves first and take the slot if it already
* exists. Perhaps we need to mark this in a variable for our
* own journal recovery? Possibly not, though we certainly
* need to warn to the user */
slot = __ocfs2_node_num_to_slot(si, osb->node_num);
if (slot < 0) {
/* if no slot yet, then just take 1st available
* one. */
slot = __ocfs2_find_empty_slot(si, osb->preferred_slot);
if (slot < 0) {
spin_unlock(&osb->osb_lock);
mlog(ML_ERROR, "no free slots available!\n");
status = -EINVAL;
goto bail;
}
} else
mlog(ML_NOTICE, "slot %d is already allocated to this node!\n",
slot);
ocfs2_set_slot(si, slot, osb->node_num);
osb->slot_num = slot;
spin_unlock(&osb->osb_lock);
mlog(0, "taking node slot %d\n", osb->slot_num);
status = ocfs2_update_disk_slot(osb, si, osb->slot_num);
if (status < 0)
mlog_errno(status);
bail:
mlog_exit(status);
return status;
}
void ocfs2_put_slot(struct ocfs2_super *osb)
{
int status, slot_num;
struct ocfs2_slot_info *si = osb->slot_info;
if (!si)
return;
spin_lock(&osb->osb_lock);
ocfs2_update_slot_info(si);
slot_num = osb->slot_num;
ocfs2_invalidate_slot(si, osb->slot_num);
osb->slot_num = OCFS2_INVALID_SLOT;
spin_unlock(&osb->osb_lock);
status = ocfs2_update_disk_slot(osb, si, slot_num);
if (status < 0) {
mlog_errno(status);
goto bail;
}
bail:
ocfs2_free_slot_info(osb);
}