[dm-devel] [PATCH] dm snapshot: use unsigned integer chunk size
Mike Snitzer
snitzer at redhat.com
Wed Sep 30 14:41:10 UTC 2009
Use unsigned integer chunk size.
Maximum chunk size is 512kB, there won't ever be need to use 4GB chunk size,
so the number can be 32-bit. This fixes compiler failure on 32-bit systems
with large block devices.
Signed-off-by: Mikulas Patocka <mpatocka at redhat.com>
Signed-off-by: Mike Snitzer <snitzer at redhat.com>
Reviewed-by: Jonathan Brassow <jbrassow at redhat.com>
---
NOTE: this patch was made to go _before_ the snapshot exception
patchset; I'll be sending [v2] of 2 patches from that series. They
needed small adjustments now that this chunk_size patch comes before
them.
---
drivers/md/dm-exception-store.c | 23 +++++++++++------------
drivers/md/dm-exception-store.h | 8 ++++----
drivers/md/dm-snap-persistent.c | 16 ++++++++--------
drivers/md/dm-snap.c | 4 ++--
4 files changed, 25 insertions(+), 26 deletions(-)
Index: linux-2.6/drivers/md/dm-snap.c
===================================================================
--- linux-2.6.orig/drivers/md/dm-snap.c
+++ linux-2.6/drivers/md/dm-snap.c
@@ -527,7 +527,7 @@ static int dm_add_exception(void *contex
static sector_t __minimum_chunk_size(struct origin *o)
{
struct dm_snapshot *snap;
- sector_t chunk_size = 0;
+ unsigned chunk_size = 0;
if (o)
list_for_each_entry(snap, &o->snapshots, list)
@@ -975,7 +975,7 @@ static void start_copy(struct dm_snap_pe
src.bdev = bdev;
src.sector = chunk_to_sector(s->store, pe->e.old_chunk);
- src.count = min(s->store->chunk_size, dev_size - src.sector);
+ src.count = min((sector_t)s->store->chunk_size, dev_size - src.sector);
dest.bdev = s->store->cow->bdev;
dest.sector = chunk_to_sector(s->store, pe->e.new_chunk);
Index: linux-2.6/drivers/md/dm-exception-store.c
===================================================================
--- linux-2.6.orig/drivers/md/dm-exception-store.c
+++ linux-2.6/drivers/md/dm-exception-store.c
@@ -141,48 +141,47 @@ EXPORT_SYMBOL(dm_exception_store_type_un
static int set_chunk_size(struct dm_exception_store *store,
const char *chunk_size_arg, char **error)
{
- unsigned long chunk_size_ulong;
+ unsigned chunk_size;
char *value;
- chunk_size_ulong = simple_strtoul(chunk_size_arg, &value, 10);
+ chunk_size = simple_strtoul(chunk_size_arg, &value, 10);
if (*chunk_size_arg == '\0' || *value != '\0') {
*error = "Invalid chunk size";
return -EINVAL;
}
- if (!chunk_size_ulong) {
+ if (!chunk_size) {
store->chunk_size = store->chunk_mask = store->chunk_shift = 0;
return 0;
}
- return dm_exception_store_set_chunk_size(store, chunk_size_ulong,
- error);
+ return dm_exception_store_set_chunk_size(store, chunk_size, error);
}
int dm_exception_store_set_chunk_size(struct dm_exception_store *store,
- unsigned long chunk_size_ulong,
+ unsigned chunk_size,
char **error)
{
/* Check chunk_size is a power of 2 */
- if (!is_power_of_2(chunk_size_ulong)) {
+ if (!is_power_of_2(chunk_size)) {
*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_logical_block_size(store->cow->bdev) >> 9)) {
+ if (chunk_size % (bdev_logical_block_size(store->cow->bdev) >> 9)) {
*error = "Chunk size is not a multiple of device blocksize";
return -EINVAL;
}
- if (chunk_size_ulong > INT_MAX >> SECTOR_SHIFT) {
+ if (chunk_size > INT_MAX >> SECTOR_SHIFT) {
*error = "Chunk size is too high";
return -EINVAL;
}
- store->chunk_size = chunk_size_ulong;
- store->chunk_mask = chunk_size_ulong - 1;
- store->chunk_shift = ffs(chunk_size_ulong) - 1;
+ store->chunk_size = chunk_size;
+ store->chunk_mask = chunk_size - 1;
+ store->chunk_shift = ffs(chunk_size) - 1;
return 0;
}
Index: linux-2.6/drivers/md/dm-exception-store.h
===================================================================
--- linux-2.6.orig/drivers/md/dm-exception-store.h
+++ linux-2.6/drivers/md/dm-exception-store.h
@@ -101,9 +101,9 @@ struct dm_exception_store {
struct dm_dev *cow;
/* Size of data blocks saved - must be a power of 2 */
- chunk_t chunk_size;
- chunk_t chunk_mask;
- chunk_t chunk_shift;
+ unsigned chunk_size;
+ unsigned chunk_mask;
+ unsigned chunk_shift;
void *context;
};
@@ -169,7 +169,7 @@ int dm_exception_store_type_register(str
int dm_exception_store_type_unregister(struct dm_exception_store_type *type);
int dm_exception_store_set_chunk_size(struct dm_exception_store *store,
- unsigned long chunk_size_ulong,
+ unsigned chunk_size,
char **error);
int dm_exception_store_create(struct dm_target *ti, int argc, char **argv,
Index: linux-2.6/drivers/md/dm-snap-persistent.c
===================================================================
--- linux-2.6.orig/drivers/md/dm-snap-persistent.c
+++ linux-2.6/drivers/md/dm-snap-persistent.c
@@ -284,12 +284,13 @@ static int read_header(struct pstore *ps
{
int r;
struct disk_header *dh;
- chunk_t chunk_size;
+ unsigned chunk_size;
int chunk_size_supplied = 1;
char *chunk_err;
/*
- * Use default chunk size (or hardsect_size, if larger) if none supplied
+ * Use default chunk size (or logical_block_size, if larger)
+ * if none supplied
*/
if (!ps->store->chunk_size) {
ps->store->chunk_size = max(DM_CHUNK_SIZE_DEFAULT_SECTORS,
@@ -334,10 +335,9 @@ static int read_header(struct pstore *ps
return 0;
if (chunk_size_supplied)
- DMWARN("chunk size %llu in device metadata overrides "
- "table chunk size of %llu.",
- (unsigned long long)chunk_size,
- (unsigned long long)ps->store->chunk_size);
+ DMWARN("chunk size %u in device metadata overrides "
+ "table chunk size of %u.",
+ chunk_size, ps->store->chunk_size);
/* We had a bogus chunk_size. Fix stuff up. */
free_area(ps);
@@ -345,8 +345,8 @@ static int read_header(struct pstore *ps
r = dm_exception_store_set_chunk_size(ps->store, chunk_size,
&chunk_err);
if (r) {
- DMERR("invalid on-disk chunk size %llu: %s.",
- (unsigned long long)chunk_size, chunk_err);
+ DMERR("invalid on-disk chunk size %u: %s.",
+ chunk_size, chunk_err);
return r;
}
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