diff options
Diffstat (limited to 'drivers/md/dm-exception-store.c')
| -rw-r--r-- | drivers/md/dm-exception-store.c | 29 |
1 files changed, 19 insertions, 10 deletions
diff --git a/drivers/md/dm-exception-store.c b/drivers/md/dm-exception-store.c index 41f408068a7c..769ab677f8e0 100644 --- a/drivers/md/dm-exception-store.c +++ b/drivers/md/dm-exception-store.c @@ -108,12 +108,12 @@ struct pstore { * Used to keep track of which metadata area the data in * 'chunk' refers to. */ - uint32_t current_area; + chunk_t current_area; /* * The next free chunk for an exception. */ - uint32_t next_free; + chunk_t next_free; /* * The index of next free exception in the current @@ -175,7 +175,7 @@ static void do_metadata(struct work_struct *work) /* * Read or write a chunk aligned and sized block of data from a device. */ -static int chunk_io(struct pstore *ps, uint32_t chunk, int rw, int metadata) +static int chunk_io(struct pstore *ps, chunk_t chunk, int rw, int metadata) { struct dm_io_region where = { .bdev = ps->snap->cow->bdev, @@ -209,16 +209,23 @@ static int chunk_io(struct pstore *ps, uint32_t chunk, int rw, int metadata) } /* + * Convert a metadata area index to a chunk index. + */ +static chunk_t area_location(struct pstore *ps, chunk_t area) +{ + return 1 + ((ps->exceptions_per_area + 1) * area); +} + +/* * Read or write a metadata area. Remembering to skip the first * chunk which holds the header. */ -static int area_io(struct pstore *ps, uint32_t area, int rw) +static int area_io(struct pstore *ps, chunk_t area, int rw) { int r; - uint32_t chunk; + chunk_t chunk; - /* convert a metadata area index to a chunk index */ - chunk = 1 + ((ps->exceptions_per_area + 1) * area); + chunk = area_location(ps, area); r = chunk_io(ps, chunk, rw, 0); if (r) @@ -228,7 +235,7 @@ static int area_io(struct pstore *ps, uint32_t area, int rw) return 0; } -static int zero_area(struct pstore *ps, uint32_t area) +static int zero_area(struct pstore *ps, chunk_t area) { memset(ps->area, 0, ps->snap->chunk_size << SECTOR_SHIFT); return area_io(ps, area, WRITE); @@ -404,7 +411,7 @@ static int insert_exceptions(struct pstore *ps, int *full) static int read_exceptions(struct pstore *ps) { - uint32_t area; + chunk_t area; int r, full = 1; /* @@ -517,6 +524,7 @@ static int persistent_prepare(struct exception_store *store, { struct pstore *ps = get_info(store); uint32_t stride; + chunk_t next_free; sector_t size = get_dev_size(store->snap->cow->bdev); /* Is there enough room ? */ @@ -530,7 +538,8 @@ static int persistent_prepare(struct exception_store *store, * into account the location of the metadata chunks. */ stride = (ps->exceptions_per_area + 1); - if ((++ps->next_free % stride) == 1) + next_free = ++ps->next_free; + if (sector_div(next_free, stride) == 1) ps->next_free++; atomic_inc(&ps->pending_count); |