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>

1 files changed, 5 insertions, 5 deletions

diff --git a/drivers/block/hd.c b/drivers/block/hd.c
index bf397bf..8a290c0 100644
--- a/drivers/block/hd.c
+++ b/drivers/block/hd.c
@@ -464,11 +464,11 @@ static void read_intr(void)
 
 ok_to_read:
 	req = hd_req;
-	insw(HD_DATA, req->buffer, 256);
+	insw(HD_DATA, bio_data(req->bio), 256);
 #ifdef DEBUG
 	printk("%s: read: sector %ld, remaining = %u, buffer=%p\n",
 	       req->rq_disk->disk_name, blk_rq_pos(req) + 1,
-	       blk_rq_sectors(req) - 1, req->buffer+512);
+	       blk_rq_sectors(req) - 1, bio_data(req->bio)+512);
 #endif
 	if (hd_end_request(0, 512)) {
 		SET_HANDLER(&read_intr);
@@ -505,7 +505,7 @@ static void write_intr(void)
 ok_to_write:
 	if (hd_end_request(0, 512)) {
 		SET_HANDLER(&write_intr);
-		outsw(HD_DATA, req->buffer, 256);
+		outsw(HD_DATA, bio_data(req->bio), 256);
 		return;
 	}
 
@@ -624,7 +624,7 @@ repeat:
 	printk("%s: %sing: CHS=%d/%d/%d, sectors=%d, buffer=%p\n",
 		req->rq_disk->disk_name,
 		req_data_dir(req) == READ ? "read" : "writ",
-		cyl, head, sec, nsect, req->buffer);
+		cyl, head, sec, nsect, bio_data(req->bio));
 #endif
 	if (req->cmd_type == REQ_TYPE_FS) {
 		switch (rq_data_dir(req)) {
@@ -643,7 +643,7 @@ repeat:
 				bad_rw_intr();
 				goto repeat;
 			}
-			outsw(HD_DATA, req->buffer, 256);
+			outsw(HD_DATA, bio_data(req->bio), 256);
 			break;
 		default:
 			printk("unknown hd-command\n");