block: remove struct request buffer member
This was used in the olden days, back when onions were proper
yellow. Basically it mapped to the current buffer to be
transferred. With highmem being added more than a decade ago,
most drivers map pages out of a bio, and rq->buffer isn't
pointing at anything valid.
Convert old style drivers to just use bio_data().
For the discard payload use case, just reference the page
in the bio.
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/drivers/block/z2ram.c b/drivers/block/z2ram.c
index 27de5046..968f9e5 100644
--- a/drivers/block/z2ram.c
+++ b/drivers/block/z2ram.c
@@ -87,13 +87,15 @@
while (len) {
unsigned long addr = start & Z2RAM_CHUNKMASK;
unsigned long size = Z2RAM_CHUNKSIZE - addr;
+ void *buffer = bio_data(req->bio);
+
if (len < size)
size = len;
addr += z2ram_map[ start >> Z2RAM_CHUNKSHIFT ];
if (rq_data_dir(req) == READ)
- memcpy(req->buffer, (char *)addr, size);
+ memcpy(buffer, (char *)addr, size);
else
- memcpy((char *)addr, req->buffer, size);
+ memcpy((char *)addr, buffer, size);
start += size;
len -= size;
}