dm snapshot: use unsigned integer chunk size

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.

Cc: stable@kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

diff --git a/drivers/md/dm-exception-store.c b/drivers/md/dm-exception-store.c
index e5de7627c52d919fe5b353c176f4e929d309b2af..932d1b123143ea87bc1c0d2ff6217b86764dfff8 100644 (file)
--- a/drivers/md/dm-exception-store.c
+++ b/drivers/md/dm-exception-store.c
@@ -155,7 +155,8 @@ static int set_chunk_size(struct dm_exception_store *store,
        char *value;
 
        chunk_size_ulong = simple_strtoul(chunk_size_arg, &value, 10);
-       if (*chunk_size_arg == '\0' || *value != '\0') {
+       if (*chunk_size_arg == '\0' || *value != '\0' ||
+           chunk_size_ulong > UINT_MAX) {
                *error = "Invalid chunk size";
                return -EINVAL;
        }
@@ -171,34 +172,35 @@ static int set_chunk_size(struct dm_exception_store *store,
         */
        chunk_size_ulong = round_up(chunk_size_ulong, PAGE_SIZE >> 9);
 
-       return dm_exception_store_set_chunk_size(store, chunk_size_ulong,
+       return dm_exception_store_set_chunk_size(store,
+                                                (unsigned) chunk_size_ulong,
                                                 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;
 }

diff --git a/drivers/md/dm-exception-store.h b/drivers/md/dm-exception-store.h
index 812c71872ba093643ba9a5e603fff2d22e4177fb..8a223a48802c0c867f79818045399937e650bf5e 100644 (file)
--- a/drivers/md/dm-exception-store.h
+++ b/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(struct dm_exception_store_type *type);
 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,

diff --git a/drivers/md/dm-snap-persistent.c b/drivers/md/dm-snap-persistent.c
index d5b2e08750d59d6574884c66424916d3d3d6f6ff..0c746420c00810f9c2e57ad346f3bd2589250821 100644 (file)
--- a/drivers/md/dm-snap-persistent.c
+++ b/drivers/md/dm-snap-persistent.c
@@ -284,12 +284,13 @@ static int read_header(struct pstore *ps, int *new_snapshot)
 {
        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, int *new_snapshot)
                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, int *new_snapshot)
        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;
        }
 

diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index 9bc814aa2bbd98d74f54bb07b8e41f3d374fff86..3a3ba46e6d4b68fc9f70b87b7ad322a8ca2c9846 100644 (file)
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -961,7 +961,7 @@ static void start_copy(struct dm_snap_pending_exception *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);
@@ -1402,7 +1402,7 @@ static void origin_resume(struct dm_target *ti)
        struct dm_dev *dev = ti->private;
        struct dm_snapshot *snap;
        struct origin *o;
-       chunk_t chunk_size = 0;
+       unsigned chunk_size = 0;
 
        down_read(&_origins_lock);
        o = __lookup_origin(dev->bdev);