From: FUJITA Tomonori chunk_io() can perform I/Os only with ps->area. This patch adds a new argument (a pointer to a buffer) to chunk_io() so that it performs I/Os with a supplied buffer. Signed-off-by: FUJITA Tomonori --- drivers/md/dm-exception-store.c | 11 ++++++----- 1 files changed, 6 insertions(+), 5 deletions(-) Index: linux-2.6.28-rc3/drivers/md/dm-exception-store.c =================================================================== --- linux-2.6.28-rc3.orig/drivers/md/dm-exception-store.c 2008-11-04 14:10:54.000000000 +0000 +++ linux-2.6.28-rc3/drivers/md/dm-exception-store.c 2008-11-07 13:15:32.000000000 +0000 @@ -188,7 +188,8 @@ static void do_metadata(struct work_stru /* * Read or write a chunk aligned and sized block of data from a device. */ -static int chunk_io(struct pstore *ps, chunk_t chunk, int rw, int metadata) +static int chunk_io(struct pstore *ps, chunk_t chunk, int rw, int metadata, + void *data) { struct dm_io_region where = { .bdev = ps->snap->cow->bdev, @@ -198,7 +199,7 @@ static int chunk_io(struct pstore *ps, c struct dm_io_request io_req = { .bi_rw = rw, .mem.type = DM_IO_VMA, - .mem.ptr.vma = ps->area, + .mem.ptr.vma = data, .client = ps->io_client, .notify.fn = NULL, }; @@ -240,7 +241,7 @@ static int area_io(struct pstore *ps, in chunk = area_location(ps, ps->current_area); - r = chunk_io(ps, chunk, rw, 0); + r = chunk_io(ps, chunk, rw, 0, ps->area); if (r) return r; @@ -297,7 +298,7 @@ static int read_header(struct pstore *ps if (r) return r; - r = chunk_io(ps, 0, READ, 1); + r = chunk_io(ps, 0, READ, 1, ps->area); if (r) goto bad; @@ -359,7 +360,7 @@ static int write_header(struct pstore *p dh->version = cpu_to_le32(ps->version); dh->chunk_size = cpu_to_le32(ps->snap->chunk_size); - return chunk_io(ps, 0, WRITE, 1); + return chunk_io(ps, 0, WRITE, 1, ps->area); } /*