From f06d9a2b52e246a66b606130cea3f0d7b7be17a7 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 23 Apr 2009 11:05:19 +0900 Subject: block: replace end_request() with [__]blk_end_request_cur() end_request() has been kept around for backward compatibility; however, it's about time for it to go away. * There aren't too many users left. * Its use of @updtodate is pretty confusing. * In some cases, newer code ends up using mixture of end_request() and [__]blk_end_request[_all](), which is way too confusing. So, add [__]blk_end_request_cur() and replace end_request() with it. Most conversions are straightforward. Noteworthy ones are... * paride/pcd: next_request() updated to take 0/-errno instead of 1/0. * paride/pf: pf_end_request() and next_request() updated to take 0/-errno instead of 1/0. * xd: xd_readwrite() updated to return 0/-errno instead of 1/0. * mtd/mtd_blkdevs: blktrans_discard_request() updated to return 0/-errno instead of 1/0. Unnecessary local variable res initialization removed from mtd_blktrans_thread(). [ Impact: cleanup ] Signed-off-by: Tejun Heo Acked-by: Joerg Dorchain Acked-by: Geert Uytterhoeven Acked-by: Grant Likely Acked-by: Laurent Vivier Cc: Tim Waugh Cc: Stephen Rothwell Cc: Paul Mackerras Cc: Jeremy Fitzhardinge Cc: Markus Lidel Cc: David Woodhouse Cc: Pete Zaitcev Cc: unsik Kim --- drivers/block/swim.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'drivers/block/swim.c') diff --git a/drivers/block/swim.c b/drivers/block/swim.c index d22cc385693..6544a7b06bf 100644 --- a/drivers/block/swim.c +++ b/drivers/block/swim.c @@ -532,39 +532,39 @@ static void redo_fd_request(struct request_queue *q) fs = req->rq_disk->private_data; if (req->sector < 0 || req->sector >= fs->total_secs) { - end_request(req, 0); + __blk_end_request_cur(req, -EIO); continue; } if (req->current_nr_sectors == 0) { - end_request(req, 1); + __blk_end_request_cur(req, 0); continue; } if (!fs->disk_in) { - end_request(req, 0); + __blk_end_request_cur(req, -EIO); continue; } if (rq_data_dir(req) == WRITE) { if (fs->write_protected) { - end_request(req, 0); + __blk_end_request_cur(req, -EIO); continue; } } switch (rq_data_dir(req)) { case WRITE: /* NOT IMPLEMENTED */ - end_request(req, 0); + __blk_end_request_cur(req, -EIO); break; case READ: if (floppy_read_sectors(fs, req->sector, req->current_nr_sectors, req->buffer)) { - end_request(req, 0); + __blk_end_request_cur(req, -EIO); continue; } req->nr_sectors -= req->current_nr_sectors; req->sector += req->current_nr_sectors; req->buffer += req->current_nr_sectors * 512; - end_request(req, 1); + __blk_end_request_cur(req, 0); break; } } -- cgit v1.2.3 From e138b4e08ef65771000fbe6d93d67e3960ff862b Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 28 Apr 2009 13:06:13 +0900 Subject: swim: clean up request completion paths swim curiously tries to update request parameters before calling __blk_end_request() when __blk_end_request() will do it anyway and unnecessarily checks whether current_nr_sectors is zero right after fetching. Drop unnecessary stuff and use standard block layer mechanisms. [ Impact: cleanup ] Signed-off-by: Tejun Heo Cc: Laurent Vivier Signed-off-by: Jens Axboe --- drivers/block/swim.c | 7 ------- 1 file changed, 7 deletions(-) (limited to 'drivers/block/swim.c') diff --git a/drivers/block/swim.c b/drivers/block/swim.c index 6544a7b06bf..97ef4266c4c 100644 --- a/drivers/block/swim.c +++ b/drivers/block/swim.c @@ -535,10 +535,6 @@ static void redo_fd_request(struct request_queue *q) __blk_end_request_cur(req, -EIO); continue; } - if (req->current_nr_sectors == 0) { - __blk_end_request_cur(req, 0); - continue; - } if (!fs->disk_in) { __blk_end_request_cur(req, -EIO); continue; @@ -561,9 +557,6 @@ static void redo_fd_request(struct request_queue *q) __blk_end_request_cur(req, -EIO); continue; } - req->nr_sectors -= req->current_nr_sectors; - req->sector += req->current_nr_sectors; - req->buffer += req->current_nr_sectors * 512; __blk_end_request_cur(req, 0); break; } -- cgit v1.2.3 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/swim.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/block/swim.c') diff --git a/drivers/block/swim.c b/drivers/block/swim.c index 97ef4266c4c..fc6a1c32293 100644 --- a/drivers/block/swim.c +++ b/drivers/block/swim.c @@ -531,7 +531,7 @@ static void redo_fd_request(struct request_queue *q) while ((req = elv_next_request(q))) { fs = req->rq_disk->private_data; - if (req->sector < 0 || req->sector >= fs->total_secs) { + if (blk_rq_pos(req) >= fs->total_secs) { __blk_end_request_cur(req, -EIO); continue; } @@ -551,8 +551,8 @@ static void redo_fd_request(struct request_queue *q) __blk_end_request_cur(req, -EIO); break; case READ: - if (floppy_read_sectors(fs, req->sector, - req->current_nr_sectors, + if (floppy_read_sectors(fs, blk_rq_pos(req), + blk_rq_cur_sectors(req), req->buffer)) { __blk_end_request_cur(req, -EIO); continue; -- cgit v1.2.3 From 06b0608e2b46465e8e663214e7db982ddb000346 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 8 May 2009 11:54:09 +0900 Subject: swim: dequeue in-flight request swim processes requests one-by-one synchronously and can easily be converted to dequeuing model. Convert it. [ Impact: dequeue in-flight request ] Signed-off-by: Tejun Heo Cc: Laurent Vivier Signed-off-by: Jens Axboe --- drivers/block/swim.c | 47 +++++++++++++++++++++++------------------------ 1 file changed, 23 insertions(+), 24 deletions(-) (limited to 'drivers/block/swim.c') diff --git a/drivers/block/swim.c b/drivers/block/swim.c index fc6a1c32293..dedd4893f5e 100644 --- a/drivers/block/swim.c +++ b/drivers/block/swim.c @@ -514,7 +514,7 @@ static int floppy_read_sectors(struct floppy_state *fs, ret = swim_read_sector(fs, side, track, sector, buffer); if (try-- == 0) - return -1; + return -EIO; } while (ret != 512); buffer += ret; @@ -528,38 +528,37 @@ static void redo_fd_request(struct request_queue *q) struct request *req; struct floppy_state *fs; - while ((req = elv_next_request(q))) { + req = elv_next_request(q); + if (req) + blkdev_dequeue_request(req); + + while (req) { + int err = -EIO; fs = req->rq_disk->private_data; - if (blk_rq_pos(req) >= fs->total_secs) { - __blk_end_request_cur(req, -EIO); - continue; - } - if (!fs->disk_in) { - __blk_end_request_cur(req, -EIO); - continue; - } - if (rq_data_dir(req) == WRITE) { - if (fs->write_protected) { - __blk_end_request_cur(req, -EIO); - continue; - } - } + if (blk_rq_pos(req) >= fs->total_secs) + goto done; + if (!fs->disk_in) + goto done; + if (rq_data_dir(req) == WRITE && fs->write_protected) + goto done; + switch (rq_data_dir(req)) { case WRITE: /* NOT IMPLEMENTED */ - __blk_end_request_cur(req, -EIO); break; case READ: - if (floppy_read_sectors(fs, blk_rq_pos(req), - blk_rq_cur_sectors(req), - req->buffer)) { - __blk_end_request_cur(req, -EIO); - continue; - } - __blk_end_request_cur(req, 0); + err = floppy_read_sectors(fs, blk_rq_pos(req), + blk_rq_cur_sectors(req), + req->buffer); break; } + done: + if (!__blk_end_request_cur(req, err)) { + req = elv_next_request(q); + if (req) + blkdev_dequeue_request(req); + } } } -- cgit v1.2.3 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/swim.c | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-) (limited to 'drivers/block/swim.c') diff --git a/drivers/block/swim.c b/drivers/block/swim.c index dedd4893f5e..cf7877fb8a7 100644 --- a/drivers/block/swim.c +++ b/drivers/block/swim.c @@ -528,10 +528,7 @@ static void redo_fd_request(struct request_queue *q) struct request *req; struct floppy_state *fs; - req = elv_next_request(q); - if (req) - blkdev_dequeue_request(req); - + req = blk_fetch_request(q); while (req) { int err = -EIO; @@ -554,11 +551,8 @@ static void redo_fd_request(struct request_queue *q) break; } done: - if (!__blk_end_request_cur(req, err)) { - req = elv_next_request(q); - if (req) - blkdev_dequeue_request(req); - } + if (!__blk_end_request_cur(req, err)) + req = blk_fetch_request(q); } } -- cgit v1.2.3