[dm-devel] [PATCH 4 of 12]: dm-exception-store-move-chunk_fields.patch
Jonathan Brassow
jbrassow at redhat.com
Tue Jan 20 19:55:23 UTC 2009
brassow
Move chunk fields from snapshot to exception store.
Signed-off-by: Jonathan Brassow <jbrassow at redhat.com>
Index: linux-2.6.28/drivers/md/dm-exception-store.c
===================================================================
--- linux-2.6.28.orig/drivers/md/dm-exception-store.c 2009-01-08 02:25:38.000000000 +0000
+++ linux-2.6.28/drivers/md/dm-exception-store.c 2009-01-08 02:25:42.000000000 +0000
@@ -143,6 +143,8 @@ int dm_exception_store_type_unregister(s
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_exception_store **store)
{
int r = 0;
@@ -162,6 +164,10 @@ int dm_exception_store_create(const char
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 = type->ctr(tmp_store, 0, NULL);
if (r) {
put_type(type);
Index: linux-2.6.28/drivers/md/dm-exception-store.h
===================================================================
--- linux-2.6.28.orig/drivers/md/dm-exception-store.h 2009-01-08 02:25:38.000000000 +0000
+++ linux-2.6.28/drivers/md/dm-exception-store.h 2009-01-08 02:25:42.000000000 +0000
@@ -99,6 +99,11 @@ struct dm_exception_store {
struct dm_snapshot *snap;
+ /* Size of data blocks saved - must be a power of 2 */
+ chunk_t chunk_size;
+ chunk_t chunk_mask;
+ chunk_t chunk_shift;
+
void *context;
};
@@ -149,6 +154,8 @@ int dm_exception_store_type_register(str
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_exception_store **store);
void dm_exception_store_destroy(struct dm_exception_store *store);
Index: linux-2.6.28/drivers/md/dm-snap-persistent.c
===================================================================
--- linux-2.6.28.orig/drivers/md/dm-snap-persistent.c 2009-01-08 02:25:34.000000000 +0000
+++ linux-2.6.28/drivers/md/dm-snap-persistent.c 2009-01-08 02:25:42.000000000 +0000
@@ -141,7 +141,7 @@ static int alloc_area(struct pstore *ps)
int r = -ENOMEM;
size_t len;
- len = ps->snap->chunk_size << SECTOR_SHIFT;
+ len = ps->snap->store->chunk_size << SECTOR_SHIFT;
/*
* Allocate the chunk_size block of memory that will hold
@@ -190,8 +190,8 @@ static int chunk_io(struct pstore *ps, c
{
struct dm_io_region where = {
.bdev = ps->snap->cow->bdev,
- .sector = ps->snap->chunk_size * chunk,
- .count = ps->snap->chunk_size,
+ .sector = ps->snap->store->chunk_size * chunk,
+ .count = ps->snap->store->chunk_size,
};
struct dm_io_request io_req = {
.bi_rw = rw,
@@ -247,15 +247,15 @@ static int area_io(struct pstore *ps, in
static void zero_memory_area(struct pstore *ps)
{
- memset(ps->area, 0, ps->snap->chunk_size << SECTOR_SHIFT);
+ memset(ps->area, 0, ps->snap->store->chunk_size << SECTOR_SHIFT);
}
static int zero_disk_area(struct pstore *ps, chunk_t area)
{
struct dm_io_region where = {
.bdev = ps->snap->cow->bdev,
- .sector = ps->snap->chunk_size * area_location(ps, area),
- .count = ps->snap->chunk_size,
+ .sector = ps->snap->store->chunk_size * area_location(ps, area),
+ .count = ps->snap->store->chunk_size,
};
struct dm_io_request io_req = {
.bi_rw = WRITE,
@@ -278,16 +278,16 @@ static int read_header(struct pstore *ps
/*
* Use default chunk size (or hardsect_size, if larger) if none supplied
*/
- if (!ps->snap->chunk_size) {
- ps->snap->chunk_size = max(DM_CHUNK_SIZE_DEFAULT_SECTORS,
+ if (!ps->snap->store->chunk_size) {
+ ps->snap->store->chunk_size = max(DM_CHUNK_SIZE_DEFAULT_SECTORS,
bdev_hardsect_size(ps->snap->cow->bdev) >> 9);
- ps->snap->chunk_mask = ps->snap->chunk_size - 1;
- ps->snap->chunk_shift = ffs(ps->snap->chunk_size) - 1;
+ ps->snap->store->chunk_mask = ps->snap->store->chunk_size - 1;
+ ps->snap->store->chunk_shift = ffs(ps->snap->store->chunk_size) - 1;
chunk_size_supplied = 0;
}
ps->io_client = dm_io_client_create(sectors_to_pages(ps->snap->
- chunk_size));
+ store->chunk_size));
if (IS_ERR(ps->io_client))
return PTR_ERR(ps->io_client);
@@ -317,22 +317,22 @@ static int read_header(struct pstore *ps
ps->version = le32_to_cpu(dh->version);
chunk_size = le32_to_cpu(dh->chunk_size);
- if (!chunk_size_supplied || ps->snap->chunk_size == chunk_size)
+ if (!chunk_size_supplied || ps->snap->store->chunk_size == chunk_size)
return 0;
DMWARN("chunk size %llu in device metadata overrides "
"table chunk size of %llu.",
(unsigned long long)chunk_size,
- (unsigned long long)ps->snap->chunk_size);
+ (unsigned long long)ps->snap->store->chunk_size);
/* We had a bogus chunk_size. Fix stuff up. */
free_area(ps);
- ps->snap->chunk_size = chunk_size;
- ps->snap->chunk_mask = chunk_size - 1;
- ps->snap->chunk_shift = ffs(chunk_size) - 1;
+ ps->snap->store->chunk_size = chunk_size;
+ ps->snap->store->chunk_mask = chunk_size - 1;
+ ps->snap->store->chunk_shift = ffs(chunk_size) - 1;
- r = dm_io_client_resize(sectors_to_pages(ps->snap->chunk_size),
+ r = dm_io_client_resize(sectors_to_pages(ps->snap->store->chunk_size),
ps->io_client);
if (r)
return r;
@@ -349,13 +349,13 @@ static int write_header(struct pstore *p
{
struct disk_header *dh;
- memset(ps->area, 0, ps->snap->chunk_size << SECTOR_SHIFT);
+ memset(ps->area, 0, ps->snap->store->chunk_size << SECTOR_SHIFT);
dh = (struct disk_header *) ps->area;
dh->magic = cpu_to_le32(SNAP_MAGIC);
dh->valid = cpu_to_le32(ps->valid);
dh->version = cpu_to_le32(ps->version);
- dh->chunk_size = cpu_to_le32(ps->snap->chunk_size);
+ dh->chunk_size = cpu_to_le32(ps->snap->store->chunk_size);
return chunk_io(ps, 0, WRITE, 1);
}
@@ -474,7 +474,7 @@ static struct pstore *get_info(struct dm
static void persistent_fraction_full(struct dm_exception_store *store,
sector_t *numerator, sector_t *denominator)
{
- *numerator = get_info(store)->next_free * store->snap->chunk_size;
+ *numerator = get_info(store)->next_free * store->chunk_size;
*denominator = get_dev_size(store->snap->cow->bdev);
}
@@ -507,7 +507,7 @@ static int persistent_read_metadata(stru
/*
* Now we know correct chunk_size, complete the initialisation.
*/
- ps->exceptions_per_area = (ps->snap->chunk_size << SECTOR_SHIFT) /
+ ps->exceptions_per_area = (ps->snap->store->chunk_size << SECTOR_SHIFT) /
sizeof(struct disk_exception);
ps->callbacks = dm_vcalloc(ps->exceptions_per_area,
sizeof(*ps->callbacks));
@@ -567,7 +567,7 @@ static int persistent_prepare_exception(
sector_t size = get_dev_size(store->snap->cow->bdev);
/* Is there enough room ? */
- if (size < ((ps->next_free + 1) * store->snap->chunk_size))
+ if (size < ((ps->next_free + 1) * store->chunk_size))
return -ENOSPC;
e->new_chunk = ps->next_free;
Index: linux-2.6.28/drivers/md/dm-snap-transient.c
===================================================================
--- linux-2.6.28.orig/drivers/md/dm-snap-transient.c 2009-01-08 02:25:34.000000000 +0000
+++ linux-2.6.28/drivers/md/dm-snap-transient.c 2009-01-08 02:26:09.000000000 +0000
@@ -42,11 +42,11 @@ static int transient_prepare_exception(s
struct transient_c *tc = store->context;
sector_t size = get_dev_size(store->snap->cow->bdev);
- if (size < (tc->next_free + store->snap->chunk_size))
+ if (size < (tc->next_free + store->chunk_size))
return -1;
e->new_chunk = sector_to_chunk(store->snap, tc->next_free);
- tc->next_free += store->snap->chunk_size;
+ tc->next_free += store->chunk_size;
return 0;
}
Index: linux-2.6.28/drivers/md/dm-snap.c
===================================================================
--- linux-2.6.28.orig/drivers/md/dm-snap.c 2009-01-08 02:25:38.000000000 +0000
+++ linux-2.6.28/drivers/md/dm-snap.c 2009-01-08 02:25:42.000000000 +0000
@@ -468,7 +468,7 @@ static int calc_max_buckets(void)
/*
* Allocate room for a suitable hash table.
*/
-static int init_hash_tables(struct dm_snapshot *s)
+static int init_hash_tables(struct dm_snapshot *s, chunk_t chunk_shift)
{
sector_t hash_size, cow_dev_size, origin_dev_size, max_buckets;
@@ -480,7 +480,7 @@ static int init_hash_tables(struct dm_sn
origin_dev_size = get_dev_size(s->origin->bdev);
max_buckets = calc_max_buckets();
- hash_size = min(origin_dev_size, cow_dev_size) >> s->chunk_shift;
+ hash_size = min(origin_dev_size, cow_dev_size) >> chunk_shift;
hash_size = min(hash_size, max_buckets);
hash_size = rounddown_pow_of_two(hash_size);
@@ -515,19 +515,20 @@ static ulong round_up(ulong n, ulong siz
}
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,
char **error)
{
- unsigned long chunk_size;
+ unsigned long chunk_size_ulong;
char *value;
- chunk_size = simple_strtoul(chunk_size_arg, &value, 10);
+ 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) {
- s->chunk_size = s->chunk_mask = s->chunk_shift = 0;
+ if (!chunk_size_ulong) {
+ *chunk_size = *chunk_mask = *chunk_shift = 0;
return 0;
}
@@ -535,23 +536,23 @@ static int set_chunk_size(struct dm_snap
* Chunk size must be multiple of page size. Silently
* round up if it's not.
*/
- chunk_size = round_up(chunk_size, PAGE_SIZE >> 9);
+ 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)) {
+ 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 % (bdev_hardsect_size(s->cow->bdev) >> 9)) {
+ if (chunk_size_ulong % (bdev_hardsect_size(s->cow->bdev) >> 9)) {
*error = "Chunk size is not a multiple of device blocksize";
return -EINVAL;
}
- s->chunk_size = chunk_size;
- s->chunk_mask = chunk_size - 1;
- s->chunk_shift = ffs(chunk_size) - 1;
+ *chunk_size = chunk_size_ulong;
+ *chunk_mask = chunk_size_ulong - 1;
+ *chunk_shift = ffs(chunk_size_ulong) - 1;
return 0;
}
@@ -567,6 +568,7 @@ static int snapshot_ctr(struct dm_target
char persistent;
char *origin_path;
char *cow_path;
+ chunk_t chunk_size, chunk_mask, chunk_shift;
if (argc != 4) {
ti->error = "requires exactly 4 arguments";
@@ -606,7 +608,8 @@ static int snapshot_ctr(struct dm_target
goto bad2;
}
- r = set_chunk_size(s, argv[3], &ti->error);
+ r = set_chunk_size(s, argv[3], &chunk_size, &chunk_mask, &chunk_shift,
+ &ti->error);
if (r)
goto bad3;
@@ -617,13 +620,14 @@ static int snapshot_ctr(struct dm_target
spin_lock_init(&s->pe_lock);
/* Allocate hash table for COW data */
- if (init_hash_tables(s)) {
+ if (init_hash_tables(s, chunk_shift)) {
ti->error = "Unable to allocate hash table space";
r = -ENOMEM;
goto bad3;
}
- r = dm_exception_store_create(argv[2], ti, &s->store);
+ r = dm_exception_store_create(argv[2], ti, chunk_size, chunk_mask,
+ chunk_shift, &s->store);
if (r) {
ti->error = "Couldn't create exception store";
r = -EINVAL;
@@ -679,7 +683,7 @@ static int snapshot_ctr(struct dm_target
}
ti->private = s;
- ti->split_io = s->chunk_size;
+ ti->split_io = s->store->chunk_size;
return 0;
@@ -954,7 +958,7 @@ static void start_copy(struct dm_snap_pe
src.bdev = bdev;
src.sector = chunk_to_sector(s, pe->e.old_chunk);
- src.count = min(s->chunk_size, dev_size - src.sector);
+ src.count = min(s->store->chunk_size, dev_size - src.sector);
dest.bdev = s->cow->bdev;
dest.sector = chunk_to_sector(s, pe->e.new_chunk);
@@ -1035,7 +1039,7 @@ static void remap_exception(struct dm_sn
bio->bi_bdev = s->cow->bdev;
bio->bi_sector = chunk_to_sector(s, dm_chunk_number(e->new_chunk) +
(chunk - e->old_chunk)) +
- (bio->bi_sector & s->chunk_mask);
+ (bio->bi_sector & s->store->chunk_mask);
}
static int snapshot_map(struct dm_target *ti, struct bio *bio,
@@ -1160,7 +1164,7 @@ static int snapshot_status(struct dm_tar
snprintf(result, maxlen, "%s %s %s %llu",
snap->origin->name, snap->cow->name,
snap->store->type->name,
- (unsigned long long)snap->chunk_size);
+ (unsigned long long)snap->store->chunk_size);
break;
}
@@ -1353,7 +1357,7 @@ static void origin_resume(struct dm_targ
o = __lookup_origin(dev->bdev);
if (o)
list_for_each_entry (snap, &o->snapshots, list)
- chunk_size = min_not_zero(chunk_size, snap->chunk_size);
+ chunk_size = min_not_zero(chunk_size, snap->store->chunk_size);
up_read(&_origins_lock);
ti->split_io = chunk_size;
Index: linux-2.6.28/drivers/md/dm-snap.h
===================================================================
--- linux-2.6.28.orig/drivers/md/dm-snap.h 2009-01-08 02:25:38.000000000 +0000
+++ linux-2.6.28/drivers/md/dm-snap.h 2009-01-08 02:25:42.000000000 +0000
@@ -32,11 +32,6 @@ struct dm_snapshot {
/* List of snapshots per Origin */
struct list_head list;
- /* Size of data blocks saved - must be a power of 2 */
- chunk_t chunk_size;
- chunk_t chunk_mask;
- chunk_t chunk_shift;
-
/* You can't use a snapshot if this is 0 (e.g. if full) */
int valid;
@@ -84,12 +79,12 @@ static inline sector_t get_dev_size(stru
static inline chunk_t sector_to_chunk(struct dm_snapshot *s, sector_t sector)
{
- return (sector & ~s->chunk_mask) >> s->chunk_shift;
+ return (sector & ~s->store->chunk_mask) >> s->store->chunk_shift;
}
static inline sector_t chunk_to_sector(struct dm_snapshot *s, chunk_t chunk)
{
- return chunk << s->chunk_shift;
+ return chunk << s->store->chunk_shift;
}
static inline int bdev_equal(struct block_device *lhs, struct block_device *rhs)
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