From 5b93629b4509c03ffa87a9316412fedf6f58cb37 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 7 May 2009 22:24:38 +0900 Subject: block: implement blk_rq_pos/[cur_]sectors() and convert obvious ones Implement accessors - blk_rq_pos(), blk_rq_sectors() and blk_rq_cur_sectors() which return rq->hard_sector, rq->hard_nr_sectors and rq->hard_cur_sectors respectively and convert direct references of the said fields to the accessors. This is in preparation of request data length handling cleanup. Geert : suggested adding const to struct request * parameter to accessors Sergei : spotted error in patch description [ Impact: cleanup ] Signed-off-by: Tejun Heo Acked-by: Geert Uytterhoeven Acked-by: Stephen Rothwell Tested-by: Grant Likely Acked-by: Grant Likely Ackec-by: Sergei Shtylyov Cc: Bartlomiej Zolnierkiewicz Cc: Borislav Petkov Cc: James Bottomley Signed-off-by: Jens Axboe --- drivers/block/viodasd.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/block/viodasd.c') diff --git a/drivers/block/viodasd.c b/drivers/block/viodasd.c index ecccf65dce2..e821eed7132 100644 --- a/drivers/block/viodasd.c +++ b/drivers/block/viodasd.c @@ -368,12 +368,12 @@ static void do_viodasd_request(struct request_queue *q) blkdev_dequeue_request(req); /* check that request contains a valid command */ if (!blk_fs_request(req)) { - viodasd_end_request(req, -EIO, req->hard_nr_sectors); + viodasd_end_request(req, -EIO, blk_rq_sectors(req)); continue; } /* Try sending the request */ if (send_request(req) != 0) - viodasd_end_request(req, -EIO, req->hard_nr_sectors); + viodasd_end_request(req, -EIO, blk_rq_sectors(req)); } } @@ -590,7 +590,7 @@ static int viodasd_handle_read_write(struct vioblocklpevent *bevent) err = vio_lookup_rc(viodasd_err_table, bevent->sub_result); printk(VIOD_KERN_WARNING "read/write error %d:0x%04x (%s)\n", event->xRc, bevent->sub_result, err->msg); - num_sect = req->hard_nr_sectors; + num_sect = blk_rq_sectors(req); } qlock = req->q->queue_lock; spin_lock_irqsave(qlock, irq_flags); -- cgit v1.2.3-18-g5258 From 83096ebf1263b2c1ee5e653ba37d993d02e3eb7b Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 7 May 2009 22:24:39 +0900 Subject: block: convert to pos and nr_sectors accessors With recent cleanups, there is no place where low level driver directly manipulates request fields. This means that the 'hard' request fields always equal the !hard fields. Convert all rq->sectors, nr_sectors and current_nr_sectors references to accessors. While at it, drop superflous blk_rq_pos() < 0 test in swim.c. [ Impact: use pos and nr_sectors accessors ] Signed-off-by: Tejun Heo Acked-by: Geert Uytterhoeven Tested-by: Grant Likely Acked-by: Grant Likely Tested-by: Adrian McMenamin Acked-by: Adrian McMenamin Acked-by: Mike Miller Cc: James Bottomley Cc: Bartlomiej Zolnierkiewicz Cc: Borislav Petkov Cc: Sergei Shtylyov Cc: Eric Moore Cc: Alan Stern Cc: FUJITA Tomonori Cc: Pete Zaitcev Cc: Stephen Rothwell Cc: Paul Clements Cc: Tim Waugh Cc: Jeff Garzik Cc: Jeremy Fitzhardinge Cc: Alex Dubov Cc: David Woodhouse Cc: Martin Schwidefsky Cc: Dario Ballabio Cc: David S. Miller Cc: Rusty Russell Cc: unsik Kim Cc: Laurent Vivier Signed-off-by: Jens Axboe --- drivers/block/viodasd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/block/viodasd.c') diff --git a/drivers/block/viodasd.c b/drivers/block/viodasd.c index e821eed7132..2086cb12d3e 100644 --- a/drivers/block/viodasd.c +++ b/drivers/block/viodasd.c @@ -252,7 +252,7 @@ static int send_request(struct request *req) struct viodasd_device *d; unsigned long flags; - start = (u64)req->sector << 9; + start = (u64)blk_rq_pos(req) << 9; if (rq_data_dir(req) == READ) { direction = DMA_FROM_DEVICE; -- cgit v1.2.3-18-g5258 From 9934c8c04561413609d2bc38c6b9f268cba774a4 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 8 May 2009 11:54:16 +0900 Subject: block: implement and enforce request peek/start/fetch Till now block layer allowed two separate modes of request execution. A request is always acquired from the request queue via elv_next_request(). After that, drivers are free to either dequeue it or process it without dequeueing. Dequeue allows elv_next_request() to return the next request so that multiple requests can be in flight. Executing requests without dequeueing has its merits mostly in allowing drivers for simpler devices which can't do sg to deal with segments only without considering request boundary. However, the benefit this brings is dubious and declining while the cost of the API ambiguity is increasing. Segment based drivers are usually for very old or limited devices and as converting to dequeueing model isn't difficult, it doesn't justify the API overhead it puts on block layer and its more modern users. Previous patches converted all block low level drivers to dequeueing model. This patch completes the API transition by... * renaming elv_next_request() to blk_peek_request() * renaming blkdev_dequeue_request() to blk_start_request() * adding blk_fetch_request() which is combination of peek and start * disallowing completion of queued (not started) requests * applying new API to all LLDs Renamings are for consistency and to break out of tree code so that it's apparent that out of tree drivers need updating. [ Impact: block request issue API cleanup, no functional change ] Signed-off-by: Tejun Heo Cc: Rusty Russell Cc: James Bottomley Cc: Mike Miller Cc: unsik Kim Cc: Paul Clements Cc: Tim Waugh Cc: Geert Uytterhoeven Cc: David S. Miller Cc: Laurent Vivier Cc: Jeff Garzik Cc: Jeremy Fitzhardinge Cc: Grant Likely Cc: Adrian McMenamin Cc: Stephen Rothwell Cc: Bartlomiej Zolnierkiewicz Cc: Borislav Petkov Cc: Sergei Shtylyov Cc: Alex Dubov Cc: Pierre Ossman Cc: David Woodhouse Cc: Markus Lidel Cc: Stefan Weinhuber Cc: Martin Schwidefsky Cc: Pete Zaitcev Cc: FUJITA Tomonori Signed-off-by: Jens Axboe --- drivers/block/viodasd.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'drivers/block/viodasd.c') diff --git a/drivers/block/viodasd.c b/drivers/block/viodasd.c index 2086cb12d3e..390d69bb7c4 100644 --- a/drivers/block/viodasd.c +++ b/drivers/block/viodasd.c @@ -361,11 +361,9 @@ static void do_viodasd_request(struct request_queue *q) * back later. */ while (num_req_outstanding < VIOMAXREQ) { - req = elv_next_request(q); + req = blk_fetch_request(q); if (req == NULL) return; - /* dequeue the current request from the queue */ - blkdev_dequeue_request(req); /* check that request contains a valid command */ if (!blk_fs_request(req)) { viodasd_end_request(req, -EIO, blk_rq_sectors(req)); -- cgit v1.2.3-18-g5258