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* cfq: Write-only stuff in CFQ data structuresAlexey Dobriyan2007-07-20
| | | | | | | | There are some leftover bits from the task cooperator patch, that was yanked out again. While it will get reintroduced, no point in having this write-only stuff in the tree. So yank it. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* cfq: async queue allocation per priorityVasily Tarasov2007-07-20
| | | | | | | | | | | | If we have two processes with different ioprio_class, but the same ioprio_data, their async requests will fall into the same queue. I guess such behavior is not expected, because it's not right to put real-time requests and best-effort requests in the same queue. The attached patch fixes the problem by introducing additional *cfqq fields on cfqd, pointing to per-(class,priority) async queues. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* mm: Remove slab destructors from kmem_cache_create().Paul Mundt2007-07-19
| | | | | | | | | | | | | | Slab destructors were no longer supported after Christoph's c59def9f222d44bb7e2f0a559f2906191a0862d7 change. They've been BUGs for both slab and slub, and slob never supported them either. This rips out support for the dtor pointer from kmem_cache_create() completely and fixes up every single callsite in the kernel (there were about 224, not including the slab allocator definitions themselves, or the documentation references). Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* some kmalloc/memset ->kzalloc (tree wide)Yoann Padioleau2007-07-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Transform some calls to kmalloc/memset to a single kzalloc (or kcalloc). Here is a short excerpt of the semantic patch performing this transformation: @@ type T2; expression x; identifier f,fld; expression E; expression E1,E2; expression e1,e2,e3,y; statement S; @@ x = - kmalloc + kzalloc (E1,E2) ... when != \(x->fld=E;\|y=f(...,x,...);\|f(...,x,...);\|x=E;\|while(...) S\|for(e1;e2;e3) S\) - memset((T2)x,0,E1); @@ expression E1,E2,E3; @@ - kzalloc(E1 * E2,E3) + kcalloc(E1,E2,E3) [akpm@linux-foundation.org: get kcalloc args the right way around] Signed-off-by: Yoann Padioleau <padator@wanadoo.fr> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Acked-by: Russell King <rmk@arm.linux.org.uk> Cc: Bryan Wu <bryan.wu@analog.com> Acked-by: Jiri Slaby <jirislaby@gmail.com> Cc: Dave Airlie <airlied@linux.ie> Acked-by: Roland Dreier <rolandd@cisco.com> Cc: Jiri Kosina <jkosina@suse.cz> Acked-by: Dmitry Torokhov <dtor@mail.ru> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Mauro Carvalho Chehab <mchehab@infradead.org> Acked-by: Pierre Ossman <drzeus-list@drzeus.cx> Cc: Jeff Garzik <jeff@garzik.org> Cc: "David S. Miller" <davem@davemloft.net> Acked-by: Greg KH <greg@kroah.com> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: "Antonino A. Daplas" <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'bsg' of git://git.kernel.dk/data/git/linux-2.6-blockLinus Torvalds2007-07-17
|\ | | | | | | | | | | | | | | | | | | | | | | | | * 'bsg' of git://git.kernel.dk/data/git/linux-2.6-block: bsg: fix missing space in version print Don't define empty struct bsg_class_device if !CONFIG_BLK_DEV_BSG bsg: Kconfig updates bsg: minor cleanup bsg: device hash table cleanup bsg: fix initialization error handling bugs bsg: mark FUJITA Tomonori as bsg maintainer bsg: convert to dynamic major bsg: address various review comments
| * bsg: fix missing space in version printJens Axboe2007-07-17
| | | | | | | | | | | | | | Tomo introduced a bug in his commit, removing the space between "driver" and "version" in the init printk. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * bsg: Kconfig updatesFUJITA Tomonori2007-07-17
| | | | | | | | | | | | | | | | | | - add the detailed explanation. - remove 'default y'. - make 'EXPERIMENTAL' keyword visible to the user in menu. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * bsg: minor cleanupFUJITA Tomonori2007-07-17
| | | | | | | | | | | | | | | | - fix MODULE_DESCRIPTION typo. - unify MODULE_DESCRIPTION and bsg_version. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * bsg: device hash table cleanupFUJITA Tomonori2007-07-17
| | | | | | | | | | | | | | | | - kill unused bsg_list_idx macro. - add bsg_dev_idx_hash() that returns an appropriate hlist_head. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * bsg: fix initialization error handling bugsFUJITA Tomonori2007-07-17
| | | | | | | | | | | | | | | | | | | | This fixes the following bugs and cleans up the initialization code: - cdev_del is missing. - unregister_chrdev_region should be used instead of unregister_chrdev. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * bsg: convert to dynamic majorJens Axboe2007-07-17
| | | | | | | | | | | | | | 240 was hardcoded, that was clearly a dumb mistake. Convert bsg to use alloc_chrdev_region() to retrieve a dynamic major. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| * bsg: address various review commentsJens Axboe2007-07-17
| | | | | | | | | | | | | | This address most of the comments made by Andrew. The two remaining are conversion to idr, and dynamic major. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* | unregister_blkdev(): return voidAkinobu Mita2007-07-17
| | | | | | | | | | | | | | | | | | | | Put WARN_ON and fixed all callers of unregister_blkdev(). Now we can make unregister_blkdev return void. Cc: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | unregister_blkdev(): do WARN_ON on failureAkinobu Mita2007-07-17
| | | | | | | | | | | | | | | | | | | | When unregister_blkdev() has failed, something wrong happened. This patch adds WARN_ON to notify of such badness. Cc: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Slab allocators: Replace explicit zeroing with __GFP_ZEROChristoph Lameter2007-07-17
|/ | | | | | | | | | | | | kmalloc_node() and kmem_cache_alloc_node() were not available in a zeroing variant in the past. But with __GFP_ZERO it is possible now to do zeroing while allocating. Use __GFP_ZERO to remove the explicit clearing of memory via memset whereever we can. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Make BLK_DEV_BSG depend strictly on SCSI=yLinus Torvalds2007-07-16
| | | | | | | | | | | | | The SCSI code can be compiled modular, but BLK_DEV_BSG currently cannot, and depends on the SCSI layer. So make sure that it depends on the SCSI layer being compiled in, not just available as a module. Noticed by Jeff Garzik and S.Çağlar Onur. Cc: Jeff Garzik <jeff@garzik.org> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: S.Çağlar Onur <caglar@pardus.org.tr> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Fix new generic block device SG compileLinus Torvalds2007-07-16
| | | | | | | | | | | We had a merge issue with the "dentry" field going away from the kobject, and being replaced by a sysfs_dirent field (named "sd") instead. That broke the BSG compile. Cc: Jens Axboe <jens.axboe@oracle.com> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: James Bottomley <James.Bottomley@SteelEye.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* bsg: Kconfig updatesFUJITA Tomonori2007-07-16
| | | | | | | | | | | This updates bsg entry in Kconfig: - bsg supports sg v4 - bsg depends on SCSI - it might be better to mark it experimental for a while Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bsg: add SCSI transport-level request supportFUJITA Tomonori2007-07-16
| | | | | | | | | | | This enables bsg to handle SCSI transport-level request like SAS management protocol (SMP). - add BSG_SUB_PROTOCOL_{SCSI_CMD, SCSI_TMF, SCSI_TRANSPORT} definitions. - SCSI transport-level requests skip blk_verify_command(). Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bsg: add bidi supportFUJITA Tomonori2007-07-16
| | | | | | | bsg uses the rq->next_rq pointer for a bidi request. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* add a struct request pointer to the request structureFUJITA Tomonori2007-07-16
| | | | | | | | | | This adds a struct request pointer to the request structure for the second data phase (bidi for now). A request queue supporting bidi requests sets QUEUE_FLAG_BIDI. This prevents sending bidi requests to a non-bidi queue. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bsg: fix the deadlock on discarding done commandsFUJITA Tomonori2007-07-16
| | | | | | | | The previous commit introduced a deadlock in discarding commands, because we forget to unlock the bd spinlock. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bsg: fix a blocking read bugFUJITA Tomonori2007-07-16
| | | | | | | | | | This patch fixes a bug that read() returns ENODATA even with a blocking file descriptor when there are no commands pending. This also includes some cleanups. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bsg: minor bug fixesFUJITA Tomonori2007-07-16
| | | | | | | | | | | | This fixes the following minor issues: - add EXPORT_SYMBOL_GPL for bsg_register_queue and bsg_unregister_queue. - shut up gcc warnings Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <axboe@nelson.home.kernel.dk>
* improve bsg device allocationFUJITA Tomonori2007-07-16
| | | | | | | | | | | | | | | | | | This patch addresses on two issues on bsg device allocation. - the current maxium number of bsg devices is 256. It's too small if we allocate bsg devices to all SCSI devices, transport entities, etc. This increses the maxium number to 32768 (taken from the sg driver). - SCSI devices are dynamically added and removed. Currently, bsg can't handle it well since bsd_device->minor is simply increased. This is dependent on the patchset that I posted yesterday: http://marc.info/?l=linux-scsi&m=117440208726755&w=2 Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bind bsg to all SCSI devicesFUJITA Tomonori2007-07-16
| | | | | | | | | | | | | This patch binds bsg to all SCSI devices (their request queues) like the current sg driver does. We can send SCSI commands to non disk and cdrom scsi devices like OSD via bsg. This patch removes bsg_register_queue from blk_register_queue so bsg devices aren't bound to non SCSI block devices. If they want bsg, I'll send a patch to do that. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bsg: bind bsg to request_queue instead of gendiskFUJITA Tomonori2007-07-16
| | | | | | | | | This patch binds bsg devices to request_queue instead of gendisk. Any objects (like transport entities) can define own request_handler and create own bsg device. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bsg: add a request_queue argument to scsi_cmd_ioctl()FUJITA Tomonori2007-07-16
| | | | | | | | | | | | bsg uses scsi_cmd_ioctl() for some SCSI/sg ioctl commands. scsi_cmd_ioctl() gets a request queue from a gendisk arguement. This prevents bsg being bound to SCSI devices that don't have a gendisk (like OSD). This adds a request_queue argument to scsi_cmd_ioctl(). The SCSI/sg ioctl commands doesn't use a gendisk so it's safe for any SCSI devices to use scsi_cmd_ioctl(). Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bsg: simplify __bsg_alloc_command failpathFUJITA Tomonori2007-07-16
| | | | | Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bsg: add cheasy error checks for sysfs stuffJens Axboe2007-07-16
| | | | Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Add queue resizing supportJens Axboe2007-07-16
| | | | | | | | | | Just get rid of the preallocated command map, use the slab cache to get/free commands instead. Original patch from FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>, changed by me to not use a mempool. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bsg: silence a bogus gcc warningJens Axboe2007-07-16
| | | | Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bsg: style cleanupJens Axboe2007-07-16
| | | | Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bsg: add SG_IO to SG v4FUJITA Tomonori2007-07-16
| | | | | | | This adds SG_IO support to SG v4. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bsg: replace SG v3 with SG v4FUJITA Tomonori2007-07-16
| | | | | | | This patch replaces SG v3 in bsg with SG v4 (except for SG_IO). Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: export blk_verify_command for SG v4FUJITA Tomonori2007-07-16
| | | | | | | | blk_fill_sghdr_rq doesn't work for SG v4 so verify_command needed to be exported. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bsg: minor cleanupsFUJITA Tomonori2007-07-16
| | | | | | | This just kills linux/config.h and dprintk warnings. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: changes for blk_rq_unmap_user new APIFUJITA Tomonori2007-07-16
| | | | | | | | | This converts block/scsi_ioctl.c use blk_rq_unmap_user new API. blk_unmap_sghdr_rq is too simple and it might be better to remove it. Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* bsg: support for full generic block layer SG v3Jens Axboe2007-07-16
| | | | Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Use list_for_each_entry() instead of list_for_each() in the block deviceMatthias Kaehlcke2007-07-10
| | | | | | | | elevator Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Use menuconfigs instead of menus, so the whole menu can be disabled at onceJan Engelhardt2007-07-10
| | | | | | | | instead of going through all options. Signed-off-by: Jan Engelhardt <jengelh@gmx.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* cfq-iosched: fix async queue behaviourJens Axboe2007-07-10
| | | | | | | | | | | With the cfq_queue hash removal, we inadvertently got rid of the async queue sharing. This was not intentional, in fact CFQ purposely shares the async queue per priority level to get good merging for async writes. So put some logic in cfq_get_queue() to track the shared queues. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* [BLOCK] drop unnecessary bvec rewinding from flush_dry_bio_endioTejun Heo2007-07-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Barrier bios are completed twice - once after the barrier write itself is done and again after the whole sequence is complete. flush_dry_bio_endio() is for the first completion. It doesn't really complete the bio. It rewinds bvec and resets bio so that it can be completed again when the whole barrier sequence is complete. The bvec rewinding code has the following problems. 1. The rewinding code is wrong because filesystems may pass bvec with non zero bv_offset. 2. The block layer doesn't guarantee anything about the state of bvec array on request completion. bv_offset and len are updated iff __end_that_request_first() completes the bvec partially. Because of #2, #1 doesn't really matter (nobody cares whether bvec is re-wound correctly or not) but then again by not doing unwinding at all, we'll always give back the same bvec to the caller as full bvec completion doesn't alter bvecs and the final completion is always full completion. Drop unnecessary rewinding code. This is spotted by Neil Brown. Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* blk_hw_contig_segment(): bad segment size checksJens Axboe2007-07-10
| | | | | | | | | | | | | | | Two bugs in there: - The virt oversize check should use the current bio hardware back size and the next bio front size, not the same bio. Spotted by Neil Brown. - The segment size check should add hw front sizes, not total bio sizes. Spotted by James Bottomley Acked-by: James Bottomley <James.Bottomley@SteelEye.com> Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* block: always requeue !fs requests at the frontTejun Heo2007-06-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SCSI marks internal commands with REQ_PREEMPT and push it at the front of the request queue using blk_execute_rq(). When entering suspended or frozen state, SCSI devices are quiesced using scsi_device_quiesce(). In quiesced state, only REQ_PREEMPT requests are processed. This is how SCSI blocks other requests out while suspending and resuming. As all internal commands are pushed at the front of the queue, this usually works. Unfortunately, this interacts badly with ordered requeueing. To preserve request order on requeueing (due to busy device, active EH or other failures), requests are sorted according to ordered sequence on requeue if IO barrier is in progress. The following sequence deadlocks. 1. IO barrier sequence issues. 2. Suspend requested. Queue is quiesced with part or all of IO barrier sequence at the front. 3. During suspending or resuming, SCSI issues internal command which gets deferred and requeued for some reason. As the command is issued after the IO barrier in #1, ordered requeueing code puts the request after IO barrier sequence. 4. The device is ready to process requests again but still is in quiesced state and the first request of the queue isn't REQ_PREEMPT, so command processing is deadlocked - suspending/resuming waits for the issued request to complete while the request can't be processed till device is put back into running state by resuming. This can be fixed by always putting !fs requests at the front when requeueing. The following thread reports this deadlock. http://thread.gmane.org/gmane.linux.kernel/537473 Signed-off-by: Tejun Heo <htejun@gmail.com> Acked-by: David Greaves <david@dgreaves.com> Acked-by: Jeff Garzik <jeff@garzik.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* genhd: send async notification on media changeKristen Carlson Accardi2007-05-23
| | | | | | | | | Send an uevent to user space to indicate that a media change event has occurred. Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* genhd: expose AN to user spaceKristen Carlson Accardi2007-05-23
| | | | | | | | | | | | Allow user space to determine if a disk supports Asynchronous Notification of media changes. This is done by adding a new sysfs file "capability_flags", which is documented in (insert file name). This sysfs file will export all disk capabilities flags to user space. We also define a new flag to define the media change notification capability. Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* ll_rw_blk: fix gcc 4.2 warning on current_io_context()Jens Axboe2007-05-15
| | | | | | | | | | | current_io_context() is both static and exported with EXPORT_SYMBOL(). As there are no users outside of ll_rw_blk.c itself, just kill the export. Problem reported by Martin Michlmayr <tbm@cyrius.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* When stacked block devices are in-use (e.g. md or dm), the recursive callsNeil Brown2007-05-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | to generic_make_request can use up a lot of space, and we would rather they didn't. As generic_make_request is a void function, and as it is generally not expected that it will have any effect immediately, it is safe to delay any call to generic_make_request until there is sufficient stack space available. As ->bi_next is reserved for the driver to use, it can have no valid value when generic_make_request is called, and as __make_request implicitly assumes it will be NULL (ELEVATOR_BACK_MERGE fork of switch) we can be certain that all callers set it to NULL. We can therefore safely use bi_next to link pending requests together, providing we clear it before making the real call. So, we choose to allow each thread to only be active in one generic_make_request at a time. If a subsequent (recursive) call is made, the bio is linked into a per-thread list, and is handled when the active call completes. As the list of pending bios is per-thread, there are no locking issues to worry about. I say above that it is "safe to delay any call...". There are, however, some behaviours of a make_request_fn which would make it unsafe. These include any behaviour that assumes anything will have changed after a recursive call to generic_make_request. These could include: - waiting for that call to finish and call it's bi_end_io function. md use to sometimes do this (marking the superblock dirty before completing a write) but doesn't any more - inspecting the bio for fields that generic_make_request might change, such as bi_sector or bi_bdev. It is hard to see a good reason for this, and I don't think anyone actually does it. - inspecing the queue to see if, e.g. it is 'full' yet. Again, I think this is very unlikely to be useful, or to be done. Signed-off-by: Neil Brown <neilb@suse.de> Cc: Jens Axboe <axboe@kernel.dk> Cc: <dm-devel@redhat.com> Alasdair G Kergon <agk@redhat.com> said: I can see nothing wrong with this in principle. For device-mapper at the moment though it's essential that, while the bio mappings may now get delayed, they still get processed in exactly the same order as they were passed to generic_make_request(). My main concern is whether the timing changes implicit in this patch will make the rare data-corrupting races in the existing snapshot code more likely. (I'm working on a fix for these races, but the unfinished patch is already several hundred lines long.) It would be helpful if some people on this mailing list would test this patch in various scenarios and report back. Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivialLinus Torvalds2007-05-09
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (25 commits) sound: convert "sound" subdirectory to UTF-8 MAINTAINERS: Add cxacru website/mailing list include files: convert "include" subdirectory to UTF-8 general: convert "kernel" subdirectory to UTF-8 documentation: convert the Documentation directory to UTF-8 Convert the toplevel files CREDITS and MAINTAINERS to UTF-8. remove broken URLs from net drivers' output Magic number prefix consistency change to Documentation/magic-number.txt trivial: s/i_sem /i_mutex/ fix file specification in comments drivers/base/platform.c: fix small typo in doc misc doc and kconfig typos Remove obsolete fat_cvf help text Fix occurrences of "the the " Fix minor typoes in kernel/module.c Kconfig: Remove reference to external mqueue library Kconfig: A couple of grammatical fixes in arch/i386/Kconfig Correct comments in genrtc.c to refer to correct /proc file. Fix more "deprecated" spellos. Fix "deprecated" typoes. ... Fix trivial comment conflict in kernel/relay.c.