mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-26 13:44:15 +08:00
dm snapshot: move ctr parsing to exception store
First step of having the exception stores parse their own arguments - generalizing the interface. Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This commit is contained in:
Jonathan Brassow
Alasdair G Kergon
parent
2e4a31df2b
commit
fee1998e9c
@ -7,6 +7,7 @@
|
||||
|
||||
#include "dm-exception-store.h"
|
||||
|
||||
#include <linux/ctype.h>
|
||||
#include <linux/mm.h>
|
||||
#include <linux/pagemap.h>
|
||||
#include <linux/vmalloc.h>
|
||||
@ -137,49 +138,129 @@ int dm_exception_store_type_unregister(struct dm_exception_store_type *type)
|
||||
}
|
||||
EXPORT_SYMBOL(dm_exception_store_type_unregister);
|
||||
|
||||
int dm_exception_store_create(const char *type_name, struct dm_target *ti,
|
||||
chunk_t chunk_size, chunk_t chunk_mask,
|
||||
chunk_t chunk_shift, struct dm_dev *cow,
|
||||
/*
|
||||
* Round a number up to the nearest 'size' boundary. size must
|
||||
* be a power of 2.
|
||||
*/
|
||||
static ulong round_up(ulong n, ulong size)
|
||||
{
|
||||
size--;
|
||||
return (n + size) & ~size;
|
||||
}
|
||||
|
||||
static int set_chunk_size(struct dm_exception_store *store,
|
||||
const char *chunk_size_arg, char **error)
|
||||
{
|
||||
unsigned long chunk_size_ulong;
|
||||
char *value;
|
||||
|
||||
chunk_size_ulong = simple_strtoul(chunk_size_arg, &value, 10);
|
||||
if (*chunk_size_arg == '\0' || *value != '\0') {
|
||||
*error = "Invalid chunk size";
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
if (!chunk_size_ulong) {
|
||||
store->chunk_size = store->chunk_mask = store->chunk_shift = 0;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Chunk size must be multiple of page size. Silently
|
||||
* round up if it's not.
|
||||
*/
|
||||
chunk_size_ulong = round_up(chunk_size_ulong, PAGE_SIZE >> 9);
|
||||
|
||||
/* Check chunk_size is a power of 2 */
|
||||
if (!is_power_of_2(chunk_size_ulong)) {
|
||||
*error = "Chunk size is not a power of 2";
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
/* Validate the chunk size against the device block size */
|
||||
if (chunk_size_ulong % (bdev_hardsect_size(store->cow->bdev) >> 9)) {
|
||||
*error = "Chunk size is not a multiple of device blocksize";
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
store->chunk_size = chunk_size_ulong;
|
||||
store->chunk_mask = chunk_size_ulong - 1;
|
||||
store->chunk_shift = ffs(chunk_size_ulong) - 1;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
int dm_exception_store_create(struct dm_target *ti, int argc, char **argv,
|
||||
unsigned *args_used,
|
||||
struct dm_exception_store **store)
|
||||
{
|
||||
int r = 0;
|
||||
struct dm_exception_store_type *type;
|
||||
struct dm_exception_store *tmp_store;
|
||||
char persistent;
|
||||
|
||||
if (argc < 3) {
|
||||
ti->error = "Insufficient exception store arguments";
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
tmp_store = kmalloc(sizeof(*tmp_store), GFP_KERNEL);
|
||||
if (!tmp_store)
|
||||
if (!tmp_store) {
|
||||
ti->error = "Exception store allocation failed";
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
type = get_type(type_name);
|
||||
if (!type) {
|
||||
kfree(tmp_store);
|
||||
persistent = toupper(*argv[1]);
|
||||
if (persistent != 'P' && persistent != 'N') {
|
||||
ti->error = "Persistent flag is not P or N";
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
type = get_type(argv[1]);
|
||||
if (!type) {
|
||||
ti->error = "Exception store type not recognised";
|
||||
r = -EINVAL;
|
||||
goto bad_type;
|
||||
}
|
||||
|
||||
tmp_store->type = type;
|
||||
tmp_store->ti = ti;
|
||||
|
||||
tmp_store->chunk_size = chunk_size;
|
||||
tmp_store->chunk_mask = chunk_mask;
|
||||
tmp_store->chunk_shift = chunk_shift;
|
||||
r = dm_get_device(ti, argv[0], 0, 0,
|
||||
FMODE_READ | FMODE_WRITE, &tmp_store->cow);
|
||||
if (r) {
|
||||
ti->error = "Cannot get COW device";
|
||||
goto bad_cow;
|
||||
}
|
||||
|
||||
tmp_store->cow = cow;
|
||||
r = set_chunk_size(tmp_store, argv[2], &ti->error);
|
||||
if (r)
|
||||
goto bad_cow;
|
||||
|
||||
r = type->ctr(tmp_store, 0, NULL);
|
||||
if (r) {
|
||||
put_type(type);
|
||||
kfree(tmp_store);
|
||||
return r;
|
||||
ti->error = "Exception store type constructor failed";
|
||||
goto bad_ctr;
|
||||
}
|
||||
|
||||
*args_used = 3;
|
||||
*store = tmp_store;
|
||||
return 0;
|
||||
|
||||
bad_ctr:
|
||||
dm_put_device(ti, tmp_store->cow);
|
||||
bad_cow:
|
||||
put_type(type);
|
||||
bad_type:
|
||||
kfree(tmp_store);
|
||||
return r;
|
||||
}
|
||||
EXPORT_SYMBOL(dm_exception_store_create);
|
||||
|
||||
void dm_exception_store_destroy(struct dm_exception_store *store)
|
||||
{
|
||||
store->type->dtr(store);
|
||||
dm_put_device(store->ti, store->cow);
|
||||
put_type(store->type);
|
||||
kfree(store);
|
||||
}
|
||||
|
||||
@ -167,9 +167,8 @@ static inline chunk_t sector_to_chunk(struct dm_exception_store *store,
|
||||
int dm_exception_store_type_register(struct dm_exception_store_type *type);
|
||||
int dm_exception_store_type_unregister(struct dm_exception_store_type *type);
|
||||
|
||||
int dm_exception_store_create(const char *type_name, struct dm_target *ti,
|
||||
chunk_t chunk_size, chunk_t chunk_mask,
|
||||
chunk_t chunk_shift, struct dm_dev *cow,
|
||||
int dm_exception_store_create(struct dm_target *ti, int argc, char **argv,
|
||||
unsigned *args_used,
|
||||
struct dm_exception_store **store);
|
||||
void dm_exception_store_destroy(struct dm_exception_store *store);
|
||||
|
||||
|
||||
@ -7,7 +7,6 @@
|
||||
*/
|
||||
|
||||
#include <linux/blkdev.h>
|
||||
#include <linux/ctype.h>
|
||||
#include <linux/device-mapper.h>
|
||||
#include <linux/delay.h>
|
||||
#include <linux/fs.h>
|
||||
@ -538,8 +537,7 @@ static int calc_max_buckets(void)
|
||||
/*
|
||||
* Allocate room for a suitable hash table.
|
||||
*/
|
||||
static int init_hash_tables(struct dm_snapshot *s, chunk_t chunk_shift,
|
||||
struct dm_dev *cow)
|
||||
static int init_hash_tables(struct dm_snapshot *s)
|
||||
{
|
||||
sector_t hash_size, cow_dev_size, origin_dev_size, max_buckets;
|
||||
|
||||
@ -547,11 +545,11 @@ static int init_hash_tables(struct dm_snapshot *s, chunk_t chunk_shift,
|
||||
* Calculate based on the size of the original volume or
|
||||
* the COW volume...
|
||||
*/
|
||||
cow_dev_size = get_dev_size(cow->bdev);
|
||||
cow_dev_size = get_dev_size(s->store->cow->bdev);
|
||||
origin_dev_size = get_dev_size(s->origin->bdev);
|
||||
max_buckets = calc_max_buckets();
|
||||
|
||||
hash_size = min(origin_dev_size, cow_dev_size) >> chunk_shift;
|
||||
hash_size = min(origin_dev_size, cow_dev_size) >> s->store->chunk_shift;
|
||||
hash_size = min(hash_size, max_buckets);
|
||||
|
||||
hash_size = rounddown_pow_of_two(hash_size);
|
||||
@ -575,60 +573,6 @@ static int init_hash_tables(struct dm_snapshot *s, chunk_t chunk_shift,
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Round a number up to the nearest 'size' boundary. size must
|
||||
* be a power of 2.
|
||||
*/
|
||||
static ulong round_up(ulong n, ulong size)
|
||||
{
|
||||
size--;
|
||||
return (n + size) & ~size;
|
||||
}
|
||||
|
||||
static int set_chunk_size(struct dm_snapshot *s, const char *chunk_size_arg,
|
||||
chunk_t *chunk_size, chunk_t *chunk_mask,
|
||||
chunk_t *chunk_shift, struct dm_dev *cow,
|
||||
char **error)
|
||||
{
|
||||
unsigned long chunk_size_ulong;
|
||||
char *value;
|
||||
|
||||
chunk_size_ulong = simple_strtoul(chunk_size_arg, &value, 10);
|
||||
if (*chunk_size_arg == '\0' || *value != '\0') {
|
||||
*error = "Invalid chunk size";
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
if (!chunk_size_ulong) {
|
||||
*chunk_size = *chunk_mask = *chunk_shift = 0;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Chunk size must be multiple of page size. Silently
|
||||
* round up if it's not.
|
||||
*/
|
||||
chunk_size_ulong = round_up(chunk_size_ulong, PAGE_SIZE >> 9);
|
||||
|
||||
/* Check chunk_size is a power of 2 */
|
||||
if (!is_power_of_2(chunk_size_ulong)) {
|
||||
*error = "Chunk size is not a power of 2";
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
/* Validate the chunk size against the device block size */
|
||||
if (chunk_size_ulong % (bdev_hardsect_size(cow->bdev) >> 9)) {
|
||||
*error = "Chunk size is not a multiple of device blocksize";
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
*chunk_size = chunk_size_ulong;
|
||||
*chunk_mask = chunk_size_ulong - 1;
|
||||
*chunk_shift = ffs(chunk_size_ulong) - 1;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Construct a snapshot mapping: <origin_dev> <COW-dev> <p/n> <chunk-size>
|
||||
*/
|
||||
@ -637,55 +581,45 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv)
|
||||
struct dm_snapshot *s;
|
||||
int i;
|
||||
int r = -EINVAL;
|
||||
char persistent;
|
||||
char *origin_path;
|
||||
char *cow_path;
|
||||
chunk_t chunk_size, chunk_mask, chunk_shift;
|
||||
struct dm_dev *cow;
|
||||
struct dm_exception_store *store;
|
||||
unsigned args_used;
|
||||
|
||||
if (argc != 4) {
|
||||
ti->error = "requires exactly 4 arguments";
|
||||
r = -EINVAL;
|
||||
goto bad1;
|
||||
goto bad_args;
|
||||
}
|
||||
|
||||
origin_path = argv[0];
|
||||
cow_path = argv[1];
|
||||
persistent = toupper(*argv[2]);
|
||||
argv++;
|
||||
argc--;
|
||||
|
||||
if (persistent != 'P' && persistent != 'N') {
|
||||
ti->error = "Persistent flag is not P or N";
|
||||
r = dm_exception_store_create(ti, argc, argv, &args_used, &store);
|
||||
if (r) {
|
||||
ti->error = "Couldn't create exception store";
|
||||
r = -EINVAL;
|
||||
goto bad1;
|
||||
goto bad_args;
|
||||
}
|
||||
|
||||
argv += args_used;
|
||||
argc -= args_used;
|
||||
|
||||
s = kmalloc(sizeof(*s), GFP_KERNEL);
|
||||
if (s == NULL) {
|
||||
if (!s) {
|
||||
ti->error = "Cannot allocate snapshot context private "
|
||||
"structure";
|
||||
r = -ENOMEM;
|
||||
goto bad1;
|
||||
goto bad_snap;
|
||||
}
|
||||
|
||||
r = dm_get_device(ti, origin_path, 0, ti->len, FMODE_READ, &s->origin);
|
||||
if (r) {
|
||||
ti->error = "Cannot get origin device";
|
||||
goto bad2;
|
||||
goto bad_origin;
|
||||
}
|
||||
|
||||
r = dm_get_device(ti, cow_path, 0, 0,
|
||||
FMODE_READ | FMODE_WRITE, &cow);
|
||||
if (r) {
|
||||
dm_put_device(ti, s->origin);
|
||||
ti->error = "Cannot get COW device";
|
||||
goto bad2;
|
||||
}
|
||||
|
||||
r = set_chunk_size(s, argv[3], &chunk_size, &chunk_mask, &chunk_shift,
|
||||
cow, &ti->error);
|
||||
if (r)
|
||||
goto bad3;
|
||||
|
||||
s->store = store;
|
||||
s->valid = 1;
|
||||
s->active = 0;
|
||||
atomic_set(&s->pending_exceptions_count, 0);
|
||||
@ -693,30 +627,22 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv)
|
||||
spin_lock_init(&s->pe_lock);
|
||||
|
||||
/* Allocate hash table for COW data */
|
||||
if (init_hash_tables(s, chunk_shift, cow)) {
|
||||
if (init_hash_tables(s)) {
|
||||
ti->error = "Unable to allocate hash table space";
|
||||
r = -ENOMEM;
|
||||
goto bad3;
|
||||
}
|
||||
|
||||
r = dm_exception_store_create(argv[2], ti, chunk_size, chunk_mask,
|
||||
chunk_shift, cow, &s->store);
|
||||
if (r) {
|
||||
ti->error = "Couldn't create exception store";
|
||||
r = -EINVAL;
|
||||
goto bad4;
|
||||
goto bad_hash_tables;
|
||||
}
|
||||
|
||||
r = dm_kcopyd_client_create(SNAPSHOT_PAGES, &s->kcopyd_client);
|
||||
if (r) {
|
||||
ti->error = "Could not create kcopyd client";
|
||||
goto bad5;
|
||||
goto bad_kcopyd;
|
||||
}
|
||||
|
||||
s->pending_pool = mempool_create_slab_pool(MIN_IOS, pending_cache);
|
||||
if (!s->pending_pool) {
|
||||
ti->error = "Could not allocate mempool for pending exceptions";
|
||||
goto bad6;
|
||||
goto bad_pending_pool;
|
||||
}
|
||||
|
||||
s->tracked_chunk_pool = mempool_create_slab_pool(MIN_IOS,
|
||||
@ -759,30 +685,29 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv)
|
||||
|
||||
return 0;
|
||||
|
||||
bad_load_and_register:
|
||||
bad_load_and_register:
|
||||
mempool_destroy(s->tracked_chunk_pool);
|
||||
|
||||
bad_tracked_chunk_pool:
|
||||
bad_tracked_chunk_pool:
|
||||
mempool_destroy(s->pending_pool);
|
||||
|
||||
bad6:
|
||||
bad_pending_pool:
|
||||
dm_kcopyd_client_destroy(s->kcopyd_client);
|
||||
|
||||
bad5:
|
||||
s->store->type->dtr(s->store);
|
||||
|
||||
bad4:
|
||||
bad_kcopyd:
|
||||
exit_exception_table(&s->pending, pending_cache);
|
||||
exit_exception_table(&s->complete, exception_cache);
|
||||
|
||||
bad3:
|
||||
dm_put_device(ti, cow);
|
||||
bad_hash_tables:
|
||||
dm_put_device(ti, s->origin);
|
||||
|
||||
bad2:
|
||||
bad_origin:
|
||||
kfree(s);
|
||||
|
||||
bad1:
|
||||
bad_snap:
|
||||
dm_exception_store_destroy(store);
|
||||
|
||||
bad_args:
|
||||
return r;
|
||||
}
|
||||
|
||||
@ -793,8 +718,6 @@ static void __free_exceptions(struct dm_snapshot *s)
|
||||
|
||||
exit_exception_table(&s->pending, pending_cache);
|
||||
exit_exception_table(&s->complete, exception_cache);
|
||||
|
||||
s->store->type->dtr(s->store);
|
||||
}
|
||||
|
||||
static void snapshot_dtr(struct dm_target *ti)
|
||||
@ -803,7 +726,6 @@ static void snapshot_dtr(struct dm_target *ti)
|
||||
int i;
|
||||
#endif
|
||||
struct dm_snapshot *s = ti->private;
|
||||
struct dm_dev *cow = s->store->cow;
|
||||
|
||||
flush_workqueue(ksnapd);
|
||||
|
||||
@ -831,7 +753,8 @@ static void snapshot_dtr(struct dm_target *ti)
|
||||
mempool_destroy(s->pending_pool);
|
||||
|
||||
dm_put_device(ti, s->origin);
|
||||
dm_put_device(ti, cow);
|
||||
|
||||
dm_exception_store_destroy(s->store);
|
||||
|
||||
kfree(s);
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user