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path: root/include/linux/bio.h
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* block: add private bio_set for bio integrity allocationsMartin K. Petersen2009-03-24
| | | | | | | | The integrity bio allocation needs its own bio_set to avoid violating the mempool allocation rules and risking deadlocks. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: Add gfp_mask parameter to bio_integrity_clone()un'ichi Nomura2009-03-14
| | | | | | | | | | | | Stricter gfp_mask might be required for clone allocation. For example, request-based dm may clone bio in interrupt context so it has to use GFP_ATOMIC. Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com> Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Cc: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: fix bad definition of BIO_RW_SYNCJens Axboe2009-02-18
| | | | | | | | We can't OR shift values, so get rid of BIO_RW_SYNC and use BIO_RW_SYNCIO and BIO_RW_UNPLUG explicitly. This brings back the behaviour from before 213d9417fec62ef4c3675621b9364a667954d4dd. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bio.h: If they MUST be inlined, then use __always_inlineAlberto Bertogli2009-02-02
| | | | | | | | bvec_kmap_irq() and bvec_kunmap_irq() comments say they MUST be inlined, so mark them as __always_inline. Signed-off-by: Alberto Bertogli <albertito@blitiri.com.ar> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Fix misleading comment in bio.hAlberto Bertogli2009-02-02
| | | | | | | | The comment says "remember to add offset!", but the function already adds it. Signed-off-by: Alberto Bertogli <albertito@blitiri.com.ar> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: add bio_rw_flagged() for testing bio->bi_rwJens Axboe2009-01-30
| | | | | | | | | | | The existing functions for checking bio->bi_rw are badly named. So lets mirror what we do for bio->bi_flags testing, use a properly named function so that it's immediately obvious what is being tested. Maintain compatability names for the old macros, eventually we'll get rid of these. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: seperate bio/request unplug and sync bitsJens Axboe2009-01-30
| | | | Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Fix small typo in bio.h's documentationAlberto Bertogli2009-01-30
| | | | | Signed-off-by: Alberto Bertogli <albertito@blitiri.com.ar> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: Don't verify integrity metadata on read errorMartin K. Petersen2009-01-30
| | | | | | | | | If we get an I/O error on a read request there is no point in doing a verify pass on the integrity buffer. Adjust the completion path accordingly. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bio: add support for inlining a number of bio_vecs inside the bioJens Axboe2008-12-29
| | | | | | | | | | | | | When we go and allocate a bio for IO, we actually do two allocations. One for the bio itself, and one for the bi_io_vec that holds the actual pages we are interested in. This feature inlines a definable amount of io vecs inside the bio itself, so we eliminate the bio_vec array allocation for IO's up to a certain size. It defaults to 4 vecs, which is typically 16k of IO. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bio: allow individual slabs in the bio_setJens Axboe2008-12-29
| | | | | | | | | | | | | | | Instead of having a global bio slab cache, add a reference to one in each bio_set that is created. This allows for personalized slabs in each bio_set, so that they can have bios of different sizes. This means we can personalize the bios we return. File systems may want to embed the bio inside another structure, to avoid allocation more items (and stuffing them in ->bi_private) after the get a bio. Or we may want to embed a number of bio_vecs directly at the end of a bio, to avoid doing two allocations to return a bio. This is now possible. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bio: move the slab pointer inside the bio_setJens Axboe2008-12-29
| | | | | | In preparation for adding differently sized bios. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bio: only mempool back the largest bio_vec slab cacheJens Axboe2008-12-29
| | | | | | | | | We only very rarely need the mempool backing, so it makes sense to get rid of all but one of the mempool in a bio_set. So keep the largest bio_vec count mempool so we can always honor the largest allocation, and "upgrade" callers that fail. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: reorder struct bio to remove padding on 64bitRichard Kennedy2008-12-29
| | | | | | | | | Remove 8 bytes of padding from struct bio which also removes 16 bytes from struct bio_pair to make it 248 bytes. bio_pair then fits into one fewer cache lines & into a smaller slab. Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: Supress Buffer I/O errors when SCSI REQ_QUIET flag setKeith Mannthey2008-12-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow the scsi request REQ_QUIET flag to be propagated to the buffer file system layer. The basic ideas is to pass the flag from the scsi request to the bio (block IO) and then to the buffer layer. The buffer layer can then suppress needless printks. This patch declutters the kernel log by removed the 40-50 (per lun) buffer io error messages seen during a boot in my multipath setup . It is a good chance any real errors will be missed in the "noise" it the logs without this patch. During boot I see blocks of messages like " __ratelimit: 211 callbacks suppressed Buffer I/O error on device sdm, logical block 5242879 Buffer I/O error on device sdm, logical block 5242879 Buffer I/O error on device sdm, logical block 5242847 Buffer I/O error on device sdm, logical block 1 Buffer I/O error on device sdm, logical block 5242878 Buffer I/O error on device sdm, logical block 5242879 Buffer I/O error on device sdm, logical block 5242879 Buffer I/O error on device sdm, logical block 5242879 Buffer I/O error on device sdm, logical block 5242879 Buffer I/O error on device sdm, logical block 5242872 " in my logs. My disk environment is multipath fiber channel using the SCSI_DH_RDAC code and multipathd. This topology includes an "active" and "ghost" path for each lun. IO's to the "ghost" path will never complete and the SCSI layer, via the scsi device handler rdac code, quick returns the IOs to theses paths and sets the REQ_QUIET scsi flag to suppress the scsi layer messages. I am wanting to extend the QUIET behavior to include the buffer file system layer to deal with these errors as well. I have been running this patch for a while now on several boxes without issue. A few runs of bonnie++ show no noticeable difference in performance in my setup. Thanks for John Stultz for the quiet_error finalization. Submitted-by: Keith Mannthey <kmannth@us.ibm.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bio: define __BIOVEC_PHYS_MERGEABLEJeremy Fitzhardinge2008-11-06
| | | | | | | | | Define __BIOVEC_PHYS_MERGEABLE as the default implementation of BIOVEC_PHYS_MERGEABLE, so that its available for reuse within an arch-specific definition of BIOVEC_PHYS_MERGEABLE. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds2008-10-17
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'for-linus' of git://git.kernel.dk/linux-2.6-block: block: remove __generic_unplug_device() from exports block: move q->unplug_work initialization blktrace: pass zfcp driver data blktrace: add support for driver data block: fix current kernel-doc warnings block: only call ->request_fn when the queue is not stopped block: simplify string handling in elv_iosched_store() block: fix kernel-doc for blk_alloc_devt() block: fix nr_phys_segments miscalculation bug block: add partition attribute for partition number block: add BIG FAT WARNING to CONFIG_DEBUG_BLOCK_EXT_DEVT softirq: Add support for triggering softirq work on softirqs.
| * block: fix nr_phys_segments miscalculation bugFUJITA Tomonori2008-10-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes the bug reported by Nikanth Karthikesan <knikanth@suse.de>: http://lkml.org/lkml/2008/10/2/203 The root cause of the bug is that blk_phys_contig_segment miscalculates q->max_segment_size. blk_phys_contig_segment checks: req->biotail->bi_size + next_req->bio->bi_size > q->max_segment_size But blk_recalc_rq_segments might expect that req->biotail and the previous bio in the req are supposed be merged into one segment. blk_recalc_rq_segments might also expect that next_req->bio and the next bio in the next_req are supposed be merged into one segment. In such case, we merge two requests that can't be merged here. Later, blk_rq_map_sg gives more segments than it should. We need to keep track of segment size in blk_recalc_rq_segments and use it to see if two requests can be merged. This patch implements it in the similar way that we used to do for hw merging (virtual merging). Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* | [SCSI] block: separate failfast into multiple bits.Mike Christie2008-10-13
|/ | | | | | | | | | | | | | | | | | | | | | Multipath is best at handling transport errors. If it gets a device error then there is not much the multipath layer can do. It will just access the same device but from a different path. This patch breaks up failfast into device, transport and driver errors. The multipath layers (md and dm mutlipath) only ask the lower levels to fast fail transport errors. The user of failfast, read ahead, will ask to fast fail on all errors. Note that blk_noretry_request will return true if any failfast bit is set. This allows drivers that do not support the multipath failfast bits to continue to fail on any failfast error like before. Drivers like scsi that are able to fail fast specific errors can check for the specific fail fast type. In the next patch I will convert scsi. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Cc: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
* block: add some comments around the bio read-write flagsJens Axboe2008-10-09
| | | | Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: mark bio_split_pool staticDenis ChengRq2008-10-09
| | | | | | | | | | | Since all bio_split calls refer the same single bio_split_pool, the bio_split function can use bio_split_pool directly instead of the mempool_t parameter; then the mempool_t parameter can be removed from bio_split param list, and bio_split_pool is only referred in fs/bio.c file, can be marked static. Signed-off-by: Denis ChengRq <crquan@gmail.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: Find bio sector offset given idx and offsetMartin K. Petersen2008-10-09
| | | | | | | | Helper function to find the sector offset in a bio given bvec index and page offset. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: Introduce integrity data ownership flagMartin K. Petersen2008-10-09
| | | | | | | | | A filesystem might supply its own integrity metadata. Introduce a flag that indicates whether the filesystem or the block layer owns the integrity buffer. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bio.h: Remove unused conditional codeAlberto Bertogli2008-10-09
| | | | | | | | The whole bio_integrity() definition is inside an #ifdef CONFIG_BLK_DEV_INTEGRITY, there's no need for the conditional code. Signed-off-by: Alberto Bertogli <albertito@blitiri.com.ar> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: add bio_kmalloc()Jens Axboe2008-10-09
| | | | | | | | | | | Not all callers need (or want!) the mempool backing guarentee, it essentially means that you can only use bio_alloc() for short allocations and not for preallocating some bio's at setup or init time. So add bio_kmalloc() which does the same thing as bio_alloc(), except it just uses kmalloc() as the backing instead of the bio mempools. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: make blk_rq_map_user take a NULL user-space bufferFUJITA Tomonori2008-10-09
| | | | | | | | | | | This patch changes blk_rq_map_user to accept a NULL user-space buffer with a READ command if rq_map_data is not NULL. Thus a caller can pass page frames to lk_rq_map_user to just set up a request and bios with page frames propely. bio_uncopy_user (called via blk_rq_unmap_user) doesn't copy data to user space with such request. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: introduce struct rq_map_data to use reserved pagesFUJITA Tomonori2008-10-09
| | | | | | | | | | | | | | | | | | | | This patch introduces struct rq_map_data to enable bio_copy_use_iov() use reserved pages. Currently, bio_copy_user_iov allocates bounce pages but drivers/scsi/sg.c wants to allocate pages by itself and use them. struct rq_map_data can be used to pass allocated pages to bio_copy_user_iov. The current users of bio_copy_user_iov simply passes NULL (they don't want to use pre-allocated pages). Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Douglas Gilbert <dougg@torque.net> Cc: Mike Christie <michaelc@cs.wisc.edu> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: add gfp_mask argument to blk_rq_map_user and blk_rq_map_user_iovFUJITA Tomonori2008-10-09
| | | | | | | | | | | | | | Currently, blk_rq_map_user and blk_rq_map_user_iov always do GFP_KERNEL allocation. This adds gfp_mask argument to blk_rq_map_user and blk_rq_map_user_iov so sg can use it (sg always does GFP_ATOMIC allocation). Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Douglas Gilbert <dougg@torque.net> Cc: Mike Christie <michaelc@cs.wisc.edu> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: add support for IO CPU affinityJens Axboe2008-10-09
| | | | | | | | | | | | | | | | | | This patch adds support for controlling the IO completion CPU of either all requests on a queue, or on a per-request basis. We export a sysfs variable (rq_affinity) which, if set, migrates completions of requests to the CPU that originally submitted it. A bio helper (bio_set_completion_cpu()) is also added, so that queuers can ask for completion on that specific CPU. In testing, this has been show to cut the system time by as much as 20-40% on synthetic workloads where CPU affinity is desired. This requires a little help from the architecture, so it'll only work as designed for archs that are using the new generic smp helper infrastructure. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: make bi_phys_segments an unsigned int instead of shortJens Axboe2008-10-09
| | | | | | | raid5 can overflow with more than 255 stripes, and we can increase it to an int for free on both 32 and 64-bit archs due to the padding. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* drop vmerge accountingMikulas Patocka2008-10-09
| | | | | | | | Remove hw_segments field from struct bio and struct request. Without virtual merge accounting they have no purpose. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: drop virtual merging accountingMikulas Patocka2008-10-09
| | | | | | | Remove virtual merge accounting. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Allow elevators to sort/merge discard requestsDavid Woodhouse2008-10-09
| | | | | | | | | | | | | But blkdev_issue_discard() still emits requests which are interpreted as soft barriers, because naïve callers might otherwise issue subsequent writes to those same sectors, which might cross on the queue (if they're reallocated quickly enough). Callers still _can_ issue non-barrier discard requests, but they have to take care of queue ordering for themselves. Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Add 'discard' request handlingDavid Woodhouse2008-10-09
| | | | | | | | | | | | | | | | | | | | Some block devices benefit from a hint that they can forget the contents of certain sectors. Add basic support for this to the block core, along with a 'blkdev_issue_discard()' helper function which issues such requests. The caller doesn't get to provide an end_io functio, since blkdev_issue_discard() will automatically split the request up into multiple bios if appropriate. Neither does the function wait for completion -- it's expected that callers won't care about when, or even _if_, the request completes. It's only a hint to the device anyway. By definition, the file system doesn't _care_ about these sectors any more. [With feedback from OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> and Jens Axboe <jens.axboe@oracle.com] Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Fix up comments about matching flags between bio and rqDavid Woodhouse2008-10-09
| | | | | Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: use bio_has_data() to check for data carrying bioJens Axboe2008-10-09
| | | | Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: add bio_has_data() to detect whether a bio carries data or notJens Axboe2008-10-09
| | | | Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: integrity cleanupsJens Axboe2008-07-03
| | | | | | | - No need to check for NULL bio, we'll get an immediate oops anyway. - Make bio_integrity() a proper function. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: Block layer data integrity supportMartin K. Petersen2008-07-03
| | | | | | | | | | | | | | | Some block devices support verifying the integrity of requests by way of checksums or other protection information that is submitted along with the I/O. This patch implements support for generating and verifying integrity metadata, as well as correctly merging, splitting and cloning bios and requests that have this extra information attached. See Documentation/block/data-integrity.txt for more information. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: Globalize bio_set and bio_vec_slabMartin K. Petersen2008-07-03
| | | | | | | | | Move struct bio_set and biovec_slab definitions to bio.h so they can be used outside of bio.c. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: add dma alignment and padding support to blk_rq_map_kernFUJITA Tomonori2008-04-29
| | | | | | | | | | | | | | | This patch adds bio_copy_kern similar to bio_copy_user. blk_rq_map_kern uses bio_copy_kern instead of bio_map_kern if necessary. bio_copy_kern uses temporary pages and the bi_end_io callback frees these pages. bio_copy_kern saves the original kernel buffer at bio->bi_private it doesn't use something like struct bio_map_data to store the information about the caller. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Tejun Heo <htejun@gmail.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: convert bio_copy_user to bio_copy_user_iovFUJITA Tomonori2008-04-21
| | | | | | | | | | | | | | | | | | | This patch enables bio_copy_user to take struct sg_iovec (renamed bio_copy_user_iov). bio_copy_user uses bio_copy_user_iov internally as bio_map_user uses bio_map_user_iov. The major changes are: - adds sg_iovec array to struct bio_map_data - adds __bio_copy_iov that copy data between bio and sg_iovec. bio_copy_user_iov and bio_uncopy_user use it. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Tejun Heo <htejun@gmail.com> Cc: Mike Christie <michaelc@cs.wisc.edu> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* fs/block_dev.c: remove #if 0'ed codeAdrian Bunk2008-02-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | Commit b2e895dbd80c420bfc0937c3729b4afe073b3848 #if 0'ed this code stating: <-- snip --> [PATCH] revert blockdev direct io back to 2.6.19 version Andrew Vasquez is reporting as-iosched oopses and a 65% throughput slowdown due to the recent special-casing of direct-io against blockdevs. We don't know why either of these things are occurring. The patch minimally reverts us back to the 2.6.19 code for a 2.6.20 release. <-- snip --> It has since been dead code, and unless someone wants to revive it now it's time to remove it. This patch also makes bio_release_pages() static again and removes the ki_bio_count member from struct kiocb, reverting changes that had been done for this dead code. Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Jens Axboe <axboe@carl.home.kernel.dk>
* block: Initial support for data-less (or empty) barrier supportJens Axboe2007-10-16
| | | | | | | | | This implements functionality to pass down or insert a barrier in a queue, without having data attached to it. The ->prepare_flush_fn() infrastructure from data barriers are reused to provide this functionality. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Drop 'size' argument from bio_endio and bi_end_ioNeilBrown2007-10-10
| | | | | | | | | | | | | As bi_end_io is only called once when the reqeust is complete, the 'size' argument is now redundant. Remove it. Now there is no need for bio_endio to subtract the size completed from bi_size. So don't do that either. While we are at it, change bi_end_io to return void. Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* BLOCK: Hide the contents of linux/bio.h if CONFIG_BLOCK=nDavid Howells2007-08-11
| | | | | | | | | | Hide the contents of linux/bio.h if CONFIG_BLOCK=n as there shouldn't be compiled code that uses it. Signed-off-by: David Howells <dhowells@redhat.com> Cc: James Bottomley <James.Bottomley@steeleye.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* [BLOCK] Don't pin lots of memory in mempoolsJens Axboe2007-04-30
| | | | | | | | | | | | | | Currently we scale the mempool sizes depending on memory installed in the machine, except for the bio pool itself which sits at a fixed 256 entry pre-allocation. There's really no point in "optimizing" this OOM path, we just need enough preallocated to make progress. A single unit is enough, lets scale it down to 2 just to be on the safe side. This patch saves ~150kb of pinned kernel memory on a 32-bit box. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* [PATCH] optimize o_direct on block devicesChen, Kenneth W2006-12-13
| | | | | | | | | | | | | | | | | | | | | | Implement block device specific .direct_IO method instead of going through generic direct_io_worker for block device. direct_io_worker() is fairly complex because it needs to handle O_DIRECT on file system, where it needs to perform block allocation, hole detection, extents file on write, and tons of other corner cases. The end result is that it takes tons of CPU time to submit an I/O. For block device, the block allocation is much simpler and a tight triple loop can be written to iterate each iovec and each page within the iovec in order to construct/prepare bio structure and then subsequently submit it to the block layer. This significantly speeds up O_D on block device. [akpm@osdl.org: small speedup] Signed-off-by: Ken Chen <kenneth.w.chen@intel.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Zach Brown <zach.brown@oracle.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Document bi_sector and sector_tRoger Gammans2006-10-04
| | | | | Signed-Off-By: Roger Gammans <rgammans@computer-surgery.co.uk> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* [PATCH] Allow file systems to differentiate between data and meta readsJens Axboe2006-09-30
| | | | | | | We can use this information for making more intelligent priority decisions, and it will also be useful for blktrace. Signed-off-by: Jens Axboe <axboe@suse.de>
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