321 lines
6.6 KiB
C
321 lines
6.6 KiB
C
/*
|
|
* Copyright (C) 2011 Red Hat, Inc.
|
|
*
|
|
* This file is released under the GPL.
|
|
*/
|
|
|
|
#include "dm-space-map-common.h"
|
|
#include "dm-space-map-disk.h"
|
|
#include "dm-space-map.h"
|
|
#include "dm-transaction-manager.h"
|
|
|
|
#include <linux/list.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/export.h>
|
|
#include <linux/device-mapper.h>
|
|
|
|
#define DM_MSG_PREFIX "space map disk"
|
|
|
|
/*----------------------------------------------------------------*/
|
|
|
|
/*
|
|
* Space map interface.
|
|
*/
|
|
struct sm_disk {
|
|
struct dm_space_map sm;
|
|
|
|
struct ll_disk ll;
|
|
struct ll_disk old_ll;
|
|
|
|
dm_block_t begin;
|
|
dm_block_t nr_allocated_this_transaction;
|
|
};
|
|
|
|
static void sm_disk_destroy(struct dm_space_map *sm)
|
|
{
|
|
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
|
|
|
|
kfree(smd);
|
|
}
|
|
|
|
static int sm_disk_extend(struct dm_space_map *sm, dm_block_t extra_blocks)
|
|
{
|
|
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
|
|
|
|
return sm_ll_extend(&smd->ll, extra_blocks);
|
|
}
|
|
|
|
static int sm_disk_get_nr_blocks(struct dm_space_map *sm, dm_block_t *count)
|
|
{
|
|
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
|
|
*count = smd->old_ll.nr_blocks;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int sm_disk_get_nr_free(struct dm_space_map *sm, dm_block_t *count)
|
|
{
|
|
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
|
|
*count = (smd->old_ll.nr_blocks - smd->old_ll.nr_allocated) - smd->nr_allocated_this_transaction;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int sm_disk_get_count(struct dm_space_map *sm, dm_block_t b,
|
|
uint32_t *result)
|
|
{
|
|
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
|
|
return sm_ll_lookup(&smd->ll, b, result);
|
|
}
|
|
|
|
static int sm_disk_count_is_more_than_one(struct dm_space_map *sm, dm_block_t b,
|
|
int *result)
|
|
{
|
|
int r;
|
|
uint32_t count;
|
|
|
|
r = sm_disk_get_count(sm, b, &count);
|
|
if (r)
|
|
return r;
|
|
|
|
*result = count > 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int sm_disk_set_count(struct dm_space_map *sm, dm_block_t b,
|
|
uint32_t count)
|
|
{
|
|
int r;
|
|
uint32_t old_count;
|
|
enum allocation_event ev;
|
|
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
|
|
|
|
r = sm_ll_insert(&smd->ll, b, count, &ev);
|
|
if (!r) {
|
|
switch (ev) {
|
|
case SM_NONE:
|
|
break;
|
|
|
|
case SM_ALLOC:
|
|
/*
|
|
* This _must_ be free in the prior transaction
|
|
* otherwise we've lost atomicity.
|
|
*/
|
|
smd->nr_allocated_this_transaction++;
|
|
break;
|
|
|
|
case SM_FREE:
|
|
/*
|
|
* It's only free if it's also free in the last
|
|
* transaction.
|
|
*/
|
|
r = sm_ll_lookup(&smd->old_ll, b, &old_count);
|
|
if (r)
|
|
return r;
|
|
|
|
if (!old_count)
|
|
smd->nr_allocated_this_transaction--;
|
|
break;
|
|
}
|
|
}
|
|
|
|
return r;
|
|
}
|
|
|
|
static int sm_disk_inc_block(struct dm_space_map *sm, dm_block_t b)
|
|
{
|
|
int r;
|
|
enum allocation_event ev;
|
|
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
|
|
|
|
r = sm_ll_inc(&smd->ll, b, &ev);
|
|
if (!r && (ev == SM_ALLOC))
|
|
/*
|
|
* This _must_ be free in the prior transaction
|
|
* otherwise we've lost atomicity.
|
|
*/
|
|
smd->nr_allocated_this_transaction++;
|
|
|
|
return r;
|
|
}
|
|
|
|
static int sm_disk_dec_block(struct dm_space_map *sm, dm_block_t b)
|
|
{
|
|
int r;
|
|
uint32_t old_count;
|
|
enum allocation_event ev;
|
|
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
|
|
|
|
r = sm_ll_dec(&smd->ll, b, &ev);
|
|
if (!r && (ev == SM_FREE)) {
|
|
/*
|
|
* It's only free if it's also free in the last
|
|
* transaction.
|
|
*/
|
|
r = sm_ll_lookup(&smd->old_ll, b, &old_count);
|
|
if (!r && !old_count)
|
|
smd->nr_allocated_this_transaction--;
|
|
}
|
|
|
|
return r;
|
|
}
|
|
|
|
static int sm_disk_new_block(struct dm_space_map *sm, dm_block_t *b)
|
|
{
|
|
int r;
|
|
enum allocation_event ev;
|
|
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
|
|
|
|
/*
|
|
* Any block we allocate has to be free in both the old and current ll.
|
|
*/
|
|
r = sm_ll_find_common_free_block(&smd->old_ll, &smd->ll, smd->begin, smd->ll.nr_blocks, b);
|
|
if (r)
|
|
return r;
|
|
|
|
smd->begin = *b + 1;
|
|
r = sm_ll_inc(&smd->ll, *b, &ev);
|
|
if (!r) {
|
|
BUG_ON(ev != SM_ALLOC);
|
|
smd->nr_allocated_this_transaction++;
|
|
}
|
|
|
|
return r;
|
|
}
|
|
|
|
static int sm_disk_commit(struct dm_space_map *sm)
|
|
{
|
|
int r;
|
|
dm_block_t nr_free;
|
|
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
|
|
|
|
r = sm_disk_get_nr_free(sm, &nr_free);
|
|
if (r)
|
|
return r;
|
|
|
|
r = sm_ll_commit(&smd->ll);
|
|
if (r)
|
|
return r;
|
|
|
|
memcpy(&smd->old_ll, &smd->ll, sizeof(smd->old_ll));
|
|
smd->begin = 0;
|
|
smd->nr_allocated_this_transaction = 0;
|
|
|
|
r = sm_disk_get_nr_free(sm, &nr_free);
|
|
if (r)
|
|
return r;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int sm_disk_root_size(struct dm_space_map *sm, size_t *result)
|
|
{
|
|
*result = sizeof(struct disk_sm_root);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int sm_disk_copy_root(struct dm_space_map *sm, void *where_le, size_t max)
|
|
{
|
|
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
|
|
struct disk_sm_root root_le;
|
|
|
|
root_le.nr_blocks = cpu_to_le64(smd->ll.nr_blocks);
|
|
root_le.nr_allocated = cpu_to_le64(smd->ll.nr_allocated);
|
|
root_le.bitmap_root = cpu_to_le64(smd->ll.bitmap_root);
|
|
root_le.ref_count_root = cpu_to_le64(smd->ll.ref_count_root);
|
|
|
|
if (max < sizeof(root_le))
|
|
return -ENOSPC;
|
|
|
|
memcpy(where_le, &root_le, sizeof(root_le));
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*----------------------------------------------------------------*/
|
|
|
|
static struct dm_space_map ops = {
|
|
.destroy = sm_disk_destroy,
|
|
.extend = sm_disk_extend,
|
|
.get_nr_blocks = sm_disk_get_nr_blocks,
|
|
.get_nr_free = sm_disk_get_nr_free,
|
|
.get_count = sm_disk_get_count,
|
|
.count_is_more_than_one = sm_disk_count_is_more_than_one,
|
|
.set_count = sm_disk_set_count,
|
|
.inc_block = sm_disk_inc_block,
|
|
.dec_block = sm_disk_dec_block,
|
|
.new_block = sm_disk_new_block,
|
|
.commit = sm_disk_commit,
|
|
.root_size = sm_disk_root_size,
|
|
.copy_root = sm_disk_copy_root,
|
|
.register_threshold_callback = NULL
|
|
};
|
|
|
|
struct dm_space_map *dm_sm_disk_create(struct dm_transaction_manager *tm,
|
|
dm_block_t nr_blocks)
|
|
{
|
|
int r;
|
|
struct sm_disk *smd;
|
|
|
|
smd = kmalloc(sizeof(*smd), GFP_KERNEL);
|
|
if (!smd)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
smd->begin = 0;
|
|
smd->nr_allocated_this_transaction = 0;
|
|
memcpy(&smd->sm, &ops, sizeof(smd->sm));
|
|
|
|
r = sm_ll_new_disk(&smd->ll, tm);
|
|
if (r)
|
|
goto bad;
|
|
|
|
r = sm_ll_extend(&smd->ll, nr_blocks);
|
|
if (r)
|
|
goto bad;
|
|
|
|
r = sm_disk_commit(&smd->sm);
|
|
if (r)
|
|
goto bad;
|
|
|
|
return &smd->sm;
|
|
|
|
bad:
|
|
kfree(smd);
|
|
return ERR_PTR(r);
|
|
}
|
|
EXPORT_SYMBOL_GPL(dm_sm_disk_create);
|
|
|
|
struct dm_space_map *dm_sm_disk_open(struct dm_transaction_manager *tm,
|
|
void *root_le, size_t len)
|
|
{
|
|
int r;
|
|
struct sm_disk *smd;
|
|
|
|
smd = kmalloc(sizeof(*smd), GFP_KERNEL);
|
|
if (!smd)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
smd->begin = 0;
|
|
smd->nr_allocated_this_transaction = 0;
|
|
memcpy(&smd->sm, &ops, sizeof(smd->sm));
|
|
|
|
r = sm_ll_open_disk(&smd->ll, tm, root_le, len);
|
|
if (r)
|
|
goto bad;
|
|
|
|
r = sm_disk_commit(&smd->sm);
|
|
if (r)
|
|
goto bad;
|
|
|
|
return &smd->sm;
|
|
|
|
bad:
|
|
kfree(smd);
|
|
return ERR_PTR(r);
|
|
}
|
|
EXPORT_SYMBOL_GPL(dm_sm_disk_open);
|
|
|
|
/*----------------------------------------------------------------*/
|