From ac0b0113ddbab3ed2388132d368c97292f9f3c84 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Sun, 19 Apr 2009 07:00:42 +0900 Subject: ide-atapi: don't abuse rq->buffer Impact: rq->buffer usage cleanup ide-atapi uses rq->buffer as private opaque value for internal special requests. rq->special isn't used for these cases (the only case where rq->special is used is for ide-tape rw requests). Use rq->special instead. Signed-off-by: Tejun Heo Cc: Jens Axboe --- drivers/ide/ide-atapi.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/ide/ide-atapi.c') diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c index 7201b176d75b..2894577237ba 100644 --- a/drivers/ide/ide-atapi.c +++ b/drivers/ide/ide-atapi.c @@ -90,7 +90,7 @@ static void ide_queue_pc_head(ide_drive_t *drive, struct gendisk *disk, blk_rq_init(NULL, rq); rq->cmd_type = REQ_TYPE_SPECIAL; rq->cmd_flags |= REQ_PREEMPT; - rq->buffer = (char *)pc; + rq->special = (char *)pc; rq->rq_disk = disk; if (pc->req_xfer) { @@ -119,7 +119,7 @@ int ide_queue_pc_tail(ide_drive_t *drive, struct gendisk *disk, rq = blk_get_request(drive->queue, READ, __GFP_WAIT); rq->cmd_type = REQ_TYPE_SPECIAL; - rq->buffer = (char *)pc; + rq->special = (char *)pc; if (pc->req_xfer) { rq->data = pc->buf; -- cgit v1.2.3 From e69d800f7e8797a8e3423380ee9d8ca1cb90c388 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Sun, 19 Apr 2009 07:00:42 +0900 Subject: ide: add helpers for preparing sense requests This is in preparation of removing the queueing of a sense request out of the IRQ handler path. Use struct request_sense as a general sense buffer for all ATAPI devices ide-{floppy,tape,cd}. tj: * blk_get_request(__GFP_WAIT) can't be called from do_request() as it can cause deadlock. Converted to use inline struct request and blk_rq_init(). * Added xfer / cdb len selection depending on device type. * All sense prep logics folded into ide_prep_sense() which never fails. * hwif->rq clearing and sense_rq used handling moved into ide_queue_sense_rq(). * blk_rq_map_kern() conversion is moved to later patch. CC: Bartlomiej Zolnierkiewicz CC: FUJITA Tomonori Signed-off-by: Borislav Petkov Signed-off-by: Tejun Heo --- drivers/ide/ide-atapi.c | 61 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) (limited to 'drivers/ide/ide-atapi.c') diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c index 2894577237ba..c6e03485a63a 100644 --- a/drivers/ide/ide-atapi.c +++ b/drivers/ide/ide-atapi.c @@ -191,6 +191,67 @@ void ide_create_request_sense_cmd(ide_drive_t *drive, struct ide_atapi_pc *pc) } EXPORT_SYMBOL_GPL(ide_create_request_sense_cmd); +void ide_prep_sense(ide_drive_t *drive, struct request *rq) +{ + struct request_sense *sense = &drive->sense_data; + struct request *sense_rq = &drive->sense_rq; + unsigned int cmd_len, sense_len; + + debug_log("%s: enter\n", __func__); + + switch (drive->media) { + case ide_floppy: + cmd_len = 255; + sense_len = 18; + break; + case ide_tape: + cmd_len = 20; + sense_len = 20; + break; + default: + cmd_len = 18; + sense_len = 18; + } + + BUG_ON(sense_len > sizeof(*sense)); + + if (blk_sense_request(rq) || drive->sense_rq_armed) + return; + + memset(sense, 0, sizeof(*sense)); + + blk_rq_init(rq->q, sense_rq); + sense_rq->rq_disk = rq->rq_disk; + + sense_rq->data = sense; + sense_rq->cmd[0] = GPCMD_REQUEST_SENSE; + sense_rq->cmd[4] = cmd_len; + sense_rq->data_len = sense_len; + + sense_rq->cmd_type = REQ_TYPE_SENSE; + sense_rq->cmd_flags |= REQ_PREEMPT; + + if (drive->media == ide_tape) + sense_rq->cmd[13] = REQ_IDETAPE_PC1; + + drive->sense_rq_armed = true; +} +EXPORT_SYMBOL_GPL(ide_prep_sense); + +void ide_queue_sense_rq(ide_drive_t *drive, void *special) +{ + BUG_ON(!drive->sense_rq_armed); + + drive->sense_rq.special = special; + drive->sense_rq_armed = false; + + drive->hwif->rq = NULL; + + elv_add_request(drive->queue, &drive->sense_rq, + ELEVATOR_INSERT_FRONT, 0); +} +EXPORT_SYMBOL_GPL(ide_queue_sense_rq); + /* * Called when an error was detected during the last packet command. * We queue a request sense packet command in the head of the request list. -- cgit v1.2.3 From 068753203e6cd085664a62e0fc0636e19b148a12 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Sun, 19 Apr 2009 07:00:42 +0900 Subject: ide-atapi: convert ide-{floppy,tape} to using preallocated sense buffer Since we're issuing REQ_TYPE_SENSE now we need to allow those types of rqs in the ->do_request callbacks. As a future improvement, sense_len assignment might be unified across all ATAPI devices. Borislav to check with specs and test. As a result, get rid of ide_queue_pc_head() and drive->request_sense_rq. tj: * Init request sense ide_atapi_pc from sense request. In the longer timer, it would probably better to fold ide_create_request_sense_cmd() into its only current user - ide_floppy_get_format_progress(). * ide_retry_pc() no longer takes @disk. CC: Bartlomiej Zolnierkiewicz CC: FUJITA Tomonori Signed-off-by: Borislav Petkov Signed-off-by: Tejun Heo --- drivers/ide/ide-atapi.c | 48 ++++++++++++++---------------------------------- 1 file changed, 14 insertions(+), 34 deletions(-) (limited to 'drivers/ide/ide-atapi.c') diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c index c6e03485a63a..972c522516f8 100644 --- a/drivers/ide/ide-atapi.c +++ b/drivers/ide/ide-atapi.c @@ -79,34 +79,6 @@ void ide_init_pc(struct ide_atapi_pc *pc) } EXPORT_SYMBOL_GPL(ide_init_pc); -/* - * Generate a new packet command request in front of the request queue, before - * the current request, so that it will be processed immediately, on the next - * pass through the driver. - */ -static void ide_queue_pc_head(ide_drive_t *drive, struct gendisk *disk, - struct ide_atapi_pc *pc, struct request *rq) -{ - blk_rq_init(NULL, rq); - rq->cmd_type = REQ_TYPE_SPECIAL; - rq->cmd_flags |= REQ_PREEMPT; - rq->special = (char *)pc; - rq->rq_disk = disk; - - if (pc->req_xfer) { - rq->data = pc->buf; - rq->data_len = pc->req_xfer; - } - - memcpy(rq->cmd, pc->c, 12); - if (drive->media == ide_tape) - rq->cmd[13] = REQ_IDETAPE_PC1; - - drive->hwif->rq = NULL; - - elv_add_request(drive->queue, rq, ELEVATOR_INSERT_FRONT, 0); -} - /* * Add a special packet command request to the tail of the request queue, * and wait for it to be serviced. @@ -254,18 +226,26 @@ EXPORT_SYMBOL_GPL(ide_queue_sense_rq); /* * Called when an error was detected during the last packet command. - * We queue a request sense packet command in the head of the request list. + * We queue a request sense packet command at the head of the request + * queue. */ -void ide_retry_pc(ide_drive_t *drive, struct gendisk *disk) +void ide_retry_pc(ide_drive_t *drive) { - struct request *rq = &drive->request_sense_rq; + struct request *sense_rq = &drive->sense_rq; struct ide_atapi_pc *pc = &drive->request_sense_pc; (void)ide_read_error(drive); - ide_create_request_sense_cmd(drive, pc); + + /* init pc from sense_rq */ + ide_init_pc(pc); + memcpy(pc->c, sense_rq->cmd, 12); + pc->buf = sense_rq->data; + pc->req_xfer = sense_rq->data_len; + if (drive->media == ide_tape) set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); - ide_queue_pc_head(drive, disk, pc, rq); + + ide_queue_sense_rq(drive, pc); } EXPORT_SYMBOL_GPL(ide_retry_pc); @@ -404,7 +384,7 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) debug_log("[cmd %x]: check condition\n", rq->cmd[0]); /* Retry operation */ - ide_retry_pc(drive, rq->rq_disk); + ide_retry_pc(drive); /* queued, but not started */ return ide_stopped; -- cgit v1.2.3 From 02e7cf8f848841ca21864ccd019e480b73c323b7 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Sun, 19 Apr 2009 07:00:42 +0900 Subject: ide-cd,atapi: use bio for internal commands Impact: unify request data buffer handling rq->data is used mostly to pass kernel buffer through request queue without using bio. There are only a couple of places which still do this in kernel and converting to bio isn't difficult. This patch converts ide-cd and atapi to use bio instead of rq->data for request sense and internal pc commands. With previous change to unify sense request handling, this is relatively easily achieved by adding blk_rq_map_kern() during sense_rq prep and PC issue. If blk_rq_map_kern() fails for sense, the error is deferred till sense issue and aborts the failed command which triggered the sense. Note that this is a slim possibility as sense prep is done on each command issue, so for the above condition to actually trigger, all preps since the last sense issue till the issue of the request which would require a sense should fail. * do_request functions might sleep now. This should be okay as ide request_fn - do_ide_request() - is invoked only from make_request and plug work. Make sure this is the case by adding might_sleep() to do_ide_request(). * Functions which access the read sense data before the sense request is complete now should access bio_data(sense_rq->bio) as the sense buffer might have been copied during blk_rq_map_kern(). * ide-tape updated to map sg. * cdrom_do_block_pc() now doesn't have to deal with REQ_TYPE_ATA_PC special case. Simplified. * tp_ops->output/input_data path dropped from ide_pc_intr(). Signed-off-by: Tejun Heo --- drivers/ide/ide-atapi.c | 52 +++++++++++++++++++++++++++++-------------------- 1 file changed, 31 insertions(+), 21 deletions(-) (limited to 'drivers/ide/ide-atapi.c') diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c index 972c522516f8..5cefe12f5622 100644 --- a/drivers/ide/ide-atapi.c +++ b/drivers/ide/ide-atapi.c @@ -94,16 +94,18 @@ int ide_queue_pc_tail(ide_drive_t *drive, struct gendisk *disk, rq->special = (char *)pc; if (pc->req_xfer) { - rq->data = pc->buf; - rq->data_len = pc->req_xfer; + error = blk_rq_map_kern(drive->queue, rq, pc->buf, pc->req_xfer, + GFP_NOIO); + if (error) + goto put_req; } memcpy(rq->cmd, pc->c, 12); if (drive->media == ide_tape) rq->cmd[13] = REQ_IDETAPE_PC1; error = blk_execute_rq(drive->queue, disk, rq, 0); +put_req: blk_put_request(rq); - return error; } EXPORT_SYMBOL_GPL(ide_queue_pc_tail); @@ -168,6 +170,7 @@ void ide_prep_sense(ide_drive_t *drive, struct request *rq) struct request_sense *sense = &drive->sense_data; struct request *sense_rq = &drive->sense_rq; unsigned int cmd_len, sense_len; + int err; debug_log("%s: enter\n", __func__); @@ -193,13 +196,19 @@ void ide_prep_sense(ide_drive_t *drive, struct request *rq) memset(sense, 0, sizeof(*sense)); blk_rq_init(rq->q, sense_rq); - sense_rq->rq_disk = rq->rq_disk; - sense_rq->data = sense; + err = blk_rq_map_kern(drive->queue, sense_rq, sense, sense_len, + GFP_NOIO); + if (unlikely(err)) { + if (printk_ratelimit()) + printk(KERN_WARNING "%s: failed to map sense buffer\n", + drive->name); + return; + } + + sense_rq->rq_disk = rq->rq_disk; sense_rq->cmd[0] = GPCMD_REQUEST_SENSE; sense_rq->cmd[4] = cmd_len; - sense_rq->data_len = sense_len; - sense_rq->cmd_type = REQ_TYPE_SENSE; sense_rq->cmd_flags |= REQ_PREEMPT; @@ -210,9 +219,14 @@ void ide_prep_sense(ide_drive_t *drive, struct request *rq) } EXPORT_SYMBOL_GPL(ide_prep_sense); -void ide_queue_sense_rq(ide_drive_t *drive, void *special) +int ide_queue_sense_rq(ide_drive_t *drive, void *special) { - BUG_ON(!drive->sense_rq_armed); + /* deferred failure from ide_prep_sense() */ + if (!drive->sense_rq_armed) { + printk(KERN_WARNING "%s: failed queue sense request\n", + drive->name); + return -ENOMEM; + } drive->sense_rq.special = special; drive->sense_rq_armed = false; @@ -221,6 +235,7 @@ void ide_queue_sense_rq(ide_drive_t *drive, void *special) elv_add_request(drive->queue, &drive->sense_rq, ELEVATOR_INSERT_FRONT, 0); + return 0; } EXPORT_SYMBOL_GPL(ide_queue_sense_rq); @@ -239,13 +254,14 @@ void ide_retry_pc(ide_drive_t *drive) /* init pc from sense_rq */ ide_init_pc(pc); memcpy(pc->c, sense_rq->cmd, 12); - pc->buf = sense_rq->data; + pc->buf = bio_data(sense_rq->bio); /* pointer to mapped address */ pc->req_xfer = sense_rq->data_len; if (drive->media == ide_tape) set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); - ide_queue_sense_rq(drive, pc); + if (ide_queue_sense_rq(drive, pc)) + ide_complete_rq(drive, -EIO, blk_rq_bytes(drive->hwif->rq)); } EXPORT_SYMBOL_GPL(ide_retry_pc); @@ -317,7 +333,6 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) struct ide_cmd *cmd = &hwif->cmd; struct request *rq = hwif->rq; const struct ide_tp_ops *tp_ops = hwif->tp_ops; - xfer_func_t *xferfunc; unsigned int timeout, done; u16 bcount; u8 stat, ireason, dsc = 0; @@ -411,7 +426,7 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) rq->errors = -EIO; } - if (drive->media == ide_tape) + if (drive->media == ide_tape && !rq->bio) done = ide_rq_bytes(rq); /* FIXME */ else done = blk_rq_bytes(rq); @@ -448,16 +463,11 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) return ide_do_reset(drive); } - xferfunc = write ? tp_ops->output_data : tp_ops->input_data; - - if (drive->media == ide_floppy && pc->buf == NULL) { + if (drive->media == ide_tape && pc->bh) + done = drive->pc_io_buffers(drive, pc, bcount, write); + else { done = min_t(unsigned int, bcount, cmd->nleft); ide_pio_bytes(drive, cmd, write, done); - } else if (drive->media == ide_tape && pc->bh) { - done = drive->pc_io_buffers(drive, pc, bcount, write); - } else { - done = min_t(unsigned int, bcount, pc->req_xfer - pc->xferred); - xferfunc(drive, NULL, pc->cur_pos, done); } /* Update the current position */ -- cgit v1.2.3 From eb6a61bb9543aa54d62595e27206b3d3c0293bcc Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Sun, 19 Apr 2009 08:46:02 +0900 Subject: ide-atapi,tape,floppy: allow ->pc_callback() to change rq->data_len Impact: allow residual count implementation in ->pc_callback() rq->data_len has two duties - carrying the number of input bytes on issue and carrying residual count back to the issuer on completion. ide-atapi completion callback ->pc_callback() is the right place to do this but currently ide-atapi depends on rq->data_len carrying the original request size after calling ->pc_callback() to complete the pc request. This patch makes ide_pc_intr(), ide_tape_issue_pc() and ide_floppy_issue_pc() cache length to complete before calling ->pc_callback() so that it can modify rq->data_len as necessary. Note: As using rq->data_len for two purposes can make cases like this incorrect in subtle ways, future changes will introduce separate field for residual count. Signed-off-by: Tejun Heo Cc: Jens Axboe --- drivers/ide/ide-atapi.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) (limited to 'drivers/ide/ide-atapi.c') diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c index 5cefe12f5622..3df5442de710 100644 --- a/drivers/ide/ide-atapi.c +++ b/drivers/ide/ide-atapi.c @@ -409,6 +409,16 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) && (stat & ATA_DSC) == 0) dsc = 1; + /* + * ->pc_callback() might change rq->data_len for + * residual count, cache total length. + */ + if (!blk_special_request(rq) && + (drive->media == ide_tape && !rq->bio)) + done = ide_rq_bytes(rq); /* FIXME */ + else + done = blk_rq_bytes(rq); + /* Command finished - Call the callback function */ uptodate = drive->pc_callback(drive, dsc); @@ -417,7 +427,6 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) if (blk_special_request(rq)) { rq->errors = 0; - done = blk_rq_bytes(rq); error = 0; } else { @@ -426,11 +435,6 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) rq->errors = -EIO; } - if (drive->media == ide_tape && !rq->bio) - done = ide_rq_bytes(rq); /* FIXME */ - else - done = blk_rq_bytes(rq); - error = uptodate ? 0 : -EIO; } -- cgit v1.2.3 From e998f30b45efb99a3c3ce7b5483f76317a17abed Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Sun, 19 Apr 2009 08:46:02 +0900 Subject: ide-tape: use standard data transfer mechanism Impact: use standard way to transfer data ide-tape uses rq in an interesting way. For r/w requests, rq->special is used to carry a private buffer management structure idetape_bh and rq->nr_sectors and current_nr_sectors are initialized to the number of idetape blocks which isn't necessary 512 bytes. Also, rq->current_nr_sectors is used to report back the residual count in units of idetape blocks. This peculiarity taxes both block layer and ide. ide-atapi has different paths and hooks to accomodate it and what a rq means becomes quite confusing and making changes at the block layer becomes quite difficult and error-prone. This patch makes ide-tape use bio instead. With the previous patch, ide-tape currently is using single contiguos buffer so replacing it isn't difficult. Data buffer is mapped into bio using blk_rq_map_kern() in idetape_queue_rw_tail(). idetape_io_buffers() and idetape_update_buffers() are dropped and pc->bh is set to null to tell ide-atapi to use standard data transfer mechanism and idetape_bh byte counts are updated by the issuer on completion using the residual count. This change also nicely removes the FIXME in ide_pc_intr() where ide-tape rqs need to be completed using ide_rq_bytes() instead of blk_rq_bytes() (although this didn't really matter as the request didn't have bio). Signed-off-by: Tejun Heo Cc: Jens Axboe --- drivers/ide/ide-atapi.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) (limited to 'drivers/ide/ide-atapi.c') diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c index 3df5442de710..b9dd4503cbc7 100644 --- a/drivers/ide/ide-atapi.c +++ b/drivers/ide/ide-atapi.c @@ -413,11 +413,7 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) * ->pc_callback() might change rq->data_len for * residual count, cache total length. */ - if (!blk_special_request(rq) && - (drive->media == ide_tape && !rq->bio)) - done = ide_rq_bytes(rq); /* FIXME */ - else - done = blk_rq_bytes(rq); + done = blk_rq_bytes(rq); /* Command finished - Call the callback function */ uptodate = drive->pc_callback(drive, dsc); -- cgit v1.2.3 From 29d1a4371035e01b0d079bc5aa88b50f5af7a566 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Sun, 19 Apr 2009 08:46:03 +0900 Subject: ide-atapi: kill unused fields and callbacks Impact: remove fields and code paths which are no longer necessary Now that ide-tape uses standard mechanisms to transfer data, special case handling for bh handling can be dropped from ide-atapi. Drop the followings. * pc->cur_pos, b_count, bh and b_data * drive->pc_update_buffers() and pc_io_buffers(). Signed-off-by: Tejun Heo --- drivers/ide/ide-atapi.c | 17 ++++------------- 1 file changed, 4 insertions(+), 13 deletions(-) (limited to 'drivers/ide/ide-atapi.c') diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c index b9dd4503cbc7..afe5a4323879 100644 --- a/drivers/ide/ide-atapi.c +++ b/drivers/ide/ide-atapi.c @@ -359,11 +359,8 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) drive->name, rq_data_dir(pc->rq) ? "write" : "read"); pc->flags |= PC_FLAG_DMA_ERROR; - } else { + } else pc->xferred = pc->req_xfer; - if (drive->pc_update_buffers) - drive->pc_update_buffers(drive, pc); - } debug_log("%s: DMA finished\n", drive->name); } @@ -463,16 +460,11 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) return ide_do_reset(drive); } - if (drive->media == ide_tape && pc->bh) - done = drive->pc_io_buffers(drive, pc, bcount, write); - else { - done = min_t(unsigned int, bcount, cmd->nleft); - ide_pio_bytes(drive, cmd, write, done); - } + done = min_t(unsigned int, bcount, cmd->nleft); + ide_pio_bytes(drive, cmd, write, done); - /* Update the current position */ + /* Update transferred byte count */ pc->xferred += done; - pc->cur_pos += done; bcount -= done; @@ -650,7 +642,6 @@ ide_startstop_t ide_issue_pc(ide_drive_t *drive, struct ide_cmd *cmd) /* We haven't transferred any data yet */ pc->xferred = 0; - pc->cur_pos = pc->buf; valid_tf = IDE_VALID_DEVICE; bcount = ((drive->media == ide_tape) ? -- cgit v1.2.3 From c3a4d78c580de4edc9ef0f7c59812fb02ceb037f Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 7 May 2009 22:24:37 +0900 Subject: block: add rq->resid_len rq->data_len served two purposes - the length of data buffer on issue and the residual count on completion. This duality creates some headaches. First of all, block layer and low level drivers can't really determine what rq->data_len contains while a request is executing. It could be the total request length or it coulde be anything else one of the lower layers is using to keep track of residual count. This complicates things because blk_rq_bytes() and thus [__]blk_end_request_all() relies on rq->data_len for PC commands. Drivers which want to report residual count should first cache the total request length, update rq->data_len and then complete the request with the cached data length. Secondly, it makes requests default to reporting full residual count, ie. reporting that no data transfer occurred. The residual count is an exception not the norm; however, the driver should clear rq->data_len to zero to signify the normal cases while leaving it alone means no data transfer occurred at all. This reverse default behavior complicates code unnecessarily and renders block PC on some drivers (ide-tape/floppy) unuseable. This patch adds rq->resid_len which is used only for residual count. While at it, remove now unnecessasry blk_rq_bytes() caching in ide_pc_intr() as rq->data_len is not changed anymore. Boaz : spotted missing conversion in osd Sergei : spotted too early conversion to blk_rq_bytes() in ide-tape [ Impact: cleanup residual count handling, report 0 resid by default ] Signed-off-by: Tejun Heo Cc: James Bottomley Cc: Bartlomiej Zolnierkiewicz Cc: Borislav Petkov Cc: Sergei Shtylyov Cc: Mike Miller Cc: Eric Moore Cc: Alan Stern Cc: FUJITA Tomonori Cc: Doug Gilbert Cc: Mike Miller Cc: Eric Moore Cc: Darrick J. Wong Cc: Pete Zaitcev Cc: Boaz Harrosh Signed-off-by: Jens Axboe --- drivers/ide/ide-atapi.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) (limited to 'drivers/ide/ide-atapi.c') diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c index afe5a4323879..e4a02a05fc81 100644 --- a/drivers/ide/ide-atapi.c +++ b/drivers/ide/ide-atapi.c @@ -367,7 +367,6 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) /* No more interrupts */ if ((stat & ATA_DRQ) == 0) { int uptodate, error; - unsigned int done; debug_log("Packet command completed, %d bytes transferred\n", pc->xferred); @@ -406,12 +405,6 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) && (stat & ATA_DSC) == 0) dsc = 1; - /* - * ->pc_callback() might change rq->data_len for - * residual count, cache total length. - */ - done = blk_rq_bytes(rq); - /* Command finished - Call the callback function */ uptodate = drive->pc_callback(drive, dsc); @@ -431,7 +424,7 @@ static ide_startstop_t ide_pc_intr(ide_drive_t *drive) error = uptodate ? 0 : -EIO; } - ide_complete_rq(drive, error, done); + ide_complete_rq(drive, error, blk_rq_bytes(rq)); return ide_stopped; } -- cgit v1.2.3 From 34b7d2c957199834c474c9d46739265643f4d9c7 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 7 May 2009 22:24:43 +0900 Subject: ide: cleanup rq->data_len usages With recent unification of fields, it's now guaranteed that rq->data_len always equals blk_rq_bytes(). Convert all direct users to accessors. [ Impact: convert direct rq->data_len usages to blk_rq_bytes() ] Signed-off-by: Tejun Heo Acked-by: Bartlomiej Zolnierkiewicz Cc: Borislav Petkov Cc: Sergei Shtylyov Signed-off-by: Jens Axboe --- drivers/ide/ide-atapi.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/ide/ide-atapi.c') diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c index e4a02a05fc81..792534db8f85 100644 --- a/drivers/ide/ide-atapi.c +++ b/drivers/ide/ide-atapi.c @@ -255,7 +255,7 @@ void ide_retry_pc(ide_drive_t *drive) ide_init_pc(pc); memcpy(pc->c, sense_rq->cmd, 12); pc->buf = bio_data(sense_rq->bio); /* pointer to mapped address */ - pc->req_xfer = sense_rq->data_len; + pc->req_xfer = blk_rq_bytes(sense_rq); if (drive->media == ide_tape) set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); @@ -303,7 +303,7 @@ int ide_cd_get_xferlen(struct request *rq) return 32768; else if (blk_sense_request(rq) || blk_pc_request(rq) || rq->cmd_type == REQ_TYPE_ATA_PC) - return rq->data_len; + return blk_rq_bytes(rq); else return 0; } -- cgit v1.2.3 From 8f6205cd572fece673da0255d74843680f67f879 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Fri, 8 May 2009 11:53:59 +0900 Subject: ide: dequeue in-flight request ide generally has single request in flight and tracks it using hwif->rq and all state handlers follow the following convention. * ide_started is returned if the request is in flight. * ide_stopped is returned if the queue needs to be restarted. The request might or might not have been processed fully or partially. * hwif->rq is set to NULL, when an issued request completes. So, dequeueing model can be implemented by dequeueing after fetch, requeueing if hwif->rq isn't NULL on ide_stopped return and doing about the same thing on completion / port unlock paths. These changes can be made in ide-io proper. In addition to the above main changes, the following updates are necessary. * ide-cd shouldn't dequeue a request when issuing REQUEST SENSE for it as the request is already dequeued. * ide-atapi uses request queue as stack when issuing REQUEST SENSE to put the REQUEST SENSE in front of the failed request. This now needs to be done using requeueing. [ Impact: dequeue in-flight request ] Signed-off-by: Tejun Heo Cc: Bartlomiej Zolnierkiewicz Cc: Borislav Petkov Cc: Sergei Shtylyov Signed-off-by: Jens Axboe --- drivers/ide/ide-atapi.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'drivers/ide/ide-atapi.c') diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c index 792534db8f85..2874c3d703a9 100644 --- a/drivers/ide/ide-atapi.c +++ b/drivers/ide/ide-atapi.c @@ -246,6 +246,7 @@ EXPORT_SYMBOL_GPL(ide_queue_sense_rq); */ void ide_retry_pc(ide_drive_t *drive) { + struct request *failed_rq = drive->hwif->rq; struct request *sense_rq = &drive->sense_rq; struct ide_atapi_pc *pc = &drive->request_sense_pc; @@ -260,8 +261,17 @@ void ide_retry_pc(ide_drive_t *drive) if (drive->media == ide_tape) set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); - if (ide_queue_sense_rq(drive, pc)) - ide_complete_rq(drive, -EIO, blk_rq_bytes(drive->hwif->rq)); + /* + * Push back the failed request and put request sense on top + * of it. The failed command will be retried after sense data + * is acquired. + */ + blk_requeue_request(failed_rq->q, failed_rq); + drive->hwif->rq = NULL; + if (ide_queue_sense_rq(drive, pc)) { + blkdev_dequeue_request(failed_rq); + ide_complete_rq(drive, -EIO, blk_rq_bytes(failed_rq)); + } } EXPORT_SYMBOL_GPL(ide_retry_pc); -- 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/ide/ide-atapi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/ide/ide-atapi.c') diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c index 2874c3d703a9..8a894fa37b53 100644 --- a/drivers/ide/ide-atapi.c +++ b/drivers/ide/ide-atapi.c @@ -269,7 +269,7 @@ void ide_retry_pc(ide_drive_t *drive) blk_requeue_request(failed_rq->q, failed_rq); drive->hwif->rq = NULL; if (ide_queue_sense_rq(drive, pc)) { - blkdev_dequeue_request(failed_rq); + blk_start_request(failed_rq); ide_complete_rq(drive, -EIO, blk_rq_bytes(failed_rq)); } } -- cgit v1.2.3