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path: root/drivers/block/null_blk.c
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2017-02-17Merge branch 'for-4.11/next' into for-4.11/linus-mergeJens Axboe
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-31block: fold cmd_type into the REQ_OP_ spaceChristoph Hellwig
Instead of keeping two levels of indirection for requests types, fold it all into the operations. The little caveat here is that previously cmd_type only applied to struct request, while the request and bio op fields were set to plain REQ_OP_READ/WRITE even for passthrough operations. Instead this patch adds new REQ_OP_* for SCSI passthrough and driver private requests, althought it has to add two for each so that we can communicate the data in/out nature of the request. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-31lightnvm: use end_io callback instead of instanceMatias Bjørling
When the lightnvm core had the "gennvm" layer between the device and the target, there was a need for the core to be able to figure out which target it should send an end_io callback to. Leading to a "double" end_io, first for the media manager instance, and then for the target instance. Now that core and gennvm is merged, there is no longer a need for this, and a single end_io callback will do. Signed-off-by: Matias Bjørling <matias@cnexlabs.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-31lightnvm: reduce number of nvm_id groups to oneMatias Bjørling
The number of configuration groups has been limited to one in current code, even if there is support for up to four. With the introduction of the open-channel SSD 1.3 specification, only a single group is exposed onwards. Reflect this in the nvm_id structure. Signed-off-by: Matias Bjørling <matias@cnexlabs.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-12-25ktime: Cleanup ktime_set() usageThomas Gleixner
ktime_set(S,N) was required for the timespec storage type and is still useful for situations where a Seconds and Nanoseconds part of a time value needs to be converted. For anything where the Seconds argument is 0, this is pointless and can be replaced with a simple assignment. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org>
2016-11-16null_blk: add usage hints for NVMYasuaki Ishimatsu
If CONFIG_NVM is disabled, loading null_block module with use_lightnvm=1 fails. But there are no messages and documents related to the failure. Add the appropriate error message. Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Massaged the text a bit. Signed-off-by: Jens Axboe <axboe@fb.com>
2016-10-09Merge branch 'for-4.9/block-irq' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull blk-mq irq/cpu mapping updates from Jens Axboe: "This is the block-irq topic branch for 4.9-rc. It's mostly from Christoph, and it allows drivers to specify their own mappings, and more importantly, to share the blk-mq mappings with the IRQ affinity mappings. It's a good step towards making this work better out of the box" * 'for-4.9/block-irq' of git://git.kernel.dk/linux-block: blk_mq: linux/blk-mq.h does not include all the headers it depends on blk-mq: kill unused blk_mq_create_mq_map() blk-mq: get rid of the cpumask in struct blk_mq_tags nvme: remove the post_scan callout nvme: switch to use pci_alloc_irq_vectors blk-mq: provide a default queue mapping for PCI device blk-mq: allow the driver to pass in a queue mapping blk-mq: remove ->map_queue blk-mq: only allocate a single mq_map per tag_set blk-mq: don't redistribute hardware queues on a CPU hotplug event
2016-09-21lightnvm: control life of nvm_dev in driverMatias Bjørling
LightNVM compatible device drivers does not have a method to expose LightNVM specific sysfs entries. To enable LightNVM sysfs entries to be exposed, lightnvm device drivers require a struct device to attach it to. To allow both the actual device driver and lightnvm sysfs entries to coexist, the device driver tracks the lifetime of the nvm_dev structure. This patch refactors NVMe and null_blk to handle the lifetime of struct nvm_dev, which eliminates the need for struct gendisk when a lightnvm compatible device is provided. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-09-21null_blk: refactor to support non-gendisk devicesMatias Bjørling
With LightNVM enabled devices, the gendisk structure is not exposed to the user. This hides the device driver specific sysfs entries, and prevents binding of LightNVM geometry information to the device. Refactor the device registration process, so that gendisk and non-gendisk devices are easily managed. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-09-15blk-mq: remove ->map_queueChristoph Hellwig
All drivers use the default, so provide an inline version of it. If we ever need other queue mapping we can add an optional method back, although supporting will also require major changes to the queue setup code. This provides better code generation, and better debugability as well. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-07-20block: get rid of bio_rw and READAChristoph Hellwig
These two are confusing leftover of the old world order, combining values of the REQ_OP_ and REQ_ namespaces. For callers that don't special case we mostly just replace bi_rw with bio_data_dir or op_is_write, except for the few cases where a switch over the REQ_OP_ values makes more sense. Any check for READA is replaced with an explicit check for REQ_RAHEAD. Also remove the READA alias for REQ_RAHEAD. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Mike Christie <mchristi@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-03-18null_blk: add lightnvm null_blk device to the nullb_listWenwei Tao
After register null_blk devices into lightnvm, we forget to add these devices to the the nullb_list, makes them invisible to the null_blk driver. Signed-off-by: Wenwei Tao <ww.tao0320@gmail.com> Fixes: a514379b0c77 ("null_blk: oops when initializing without lightnvm") Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-11null_blk: oops when initializing without lightnvmMatias Bjørling
If the LightNVM subsystem is not compiled into the kernel, and the null_blk device driver requests lightnvm to be initialized. The call to nvm_register fails and the null_add_dev function cleans up the initialization. However, at this point the null block device has already been added to the nullb_list and thus a second cleanup will occur when the function has returned, that leads to a double call to blk_cleanup_queue. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-02-04lightnvm: allow to force mm initializationMatias Bjørling
System block allows the device to initialize with its configured media manager. The system blocks is written to disk, and read again when media manager is determined. For this to work, the backend must store the data. Device drivers, such as null_blk, does not have any backend storage. This patch allows the media manager to be initialized without a storage backend. It also fix incorrect configuration of capabilities in null_blk, as it does not support get/set bad block interface. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-21Merge branch 'for-4.5/lightnvm' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull lightnvm fixes and updates from Jens Axboe: "This should have been part of the drivers branch, but it arrived a bit late and wasn't based on the official core block driver branch. So they got a small scolding, but got a pass since it's still new. Hence it's in a separate branch. This is mostly pure fixes, contained to lightnvm/, and minor feature additions" * 'for-4.5/lightnvm' of git://git.kernel.dk/linux-block: (26 commits) lightnvm: ensure that nvm_dev_ops can be used without CONFIG_NVM lightnvm: introduce factory reset lightnvm: use system block for mm initialization lightnvm: introduce ioctl to initialize device lightnvm: core on-disk initialization lightnvm: introduce mlc lower page table mappings lightnvm: add mccap support lightnvm: manage open and closed blocks separately lightnvm: fix missing grown bad block type lightnvm: reference rrpc lun in rrpc block lightnvm: introduce nvm_submit_ppa lightnvm: move rq->error to nvm_rq->error lightnvm: support multiple ppas in nvm_erase_ppa lightnvm: move the pages per block check out of the loop lightnvm: sectors first in ppa list lightnvm: fix locking and mempool in rrpc_lun_gc lightnvm: put block back to gc list on its reclaim fail lightnvm: check bi_error in gc lightnvm: return the get_bb_tbl return value lightnvm: refactor end_io functions for sync ...
2016-01-21Merge branch 'for-4.5/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block driver updates from Jens Axboe: "This is the block driver pull request for 4.5, with the exception of NVMe, which is in a separate branch and will be posted after this one. This pull request contains: - A set of bcache stability fixes, which have been acked by Kent. These have been used and tested for more than a year by the community, so it's about time that they got in. - A set of drbd updates from the drbd team (Andreas, Lars, Philipp) and Markus Elfring, Oleg Drokin. - A set of fixes for xen blkback/front from the usual suspects, (Bob, Konrad) as well as community based fixes from Kiri, Julien, and Peng. - A 2038 time fix for sx8 from Shraddha, with a fix from me. - A small mtip32xx cleanup from Zhu Yanjun. - A null_blk division fix from Arnd" * 'for-4.5/drivers' of git://git.kernel.dk/linux-block: (71 commits) null_blk: use sector_div instead of do_div mtip32xx: restrict variables visible in current code module xen/blkfront: Fix crash if backend doesn't follow the right states. xen/blkback: Fix two memory leaks. xen/blkback: make st_ statistics per ring xen/blkfront: Handle non-indirect grant with 64KB pages xen-blkfront: Introduce blkif_ring_get_request xen-blkback: clear PF_NOFREEZE for xen_blkif_schedule() xen/blkback: Free resources if connect_ring failed. xen/blocks: Return -EXX instead of -1 xen/blkback: make pool of persistent grants and free pages per-queue xen/blkback: get the number of hardware queues/rings from blkfront xen/blkback: pseudo support for multi hardware queues/rings xen/blkback: separate ring information out of struct xen_blkif xen/blkfront: correct setting for xen_blkif_max_ring_order xen/blkfront: make persistent grants pool per-queue xen/blkfront: Remove duplicate setting of ->xbdev. xen/blkfront: Cleanup of comments, fix unaligned variables, and syntax errors. xen/blkfront: negotiate number of queues/rings to be used with backend xen/blkfront: split per device io_lock ...
2016-01-19Merge branch 'for-4.5/core' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull core block updates from Jens Axboe: "We don't have a lot of core changes this time around, it's mostly in drivers, which will come in a subsequent pull. The cores changes include: - blk-mq - Prep patch from Christoph, changing blk_mq_alloc_request() to take flags instead of just using gfp_t for sleep/nosleep. - Doc patch from me, clarifying the difference between legacy and blk-mq for timer usage. - Fixes from Raghavendra for memory-less numa nodes, and a reuse of CPU masks. - Cleanup from Geliang Tang, using offset_in_page() instead of open coding it. - From Ilya, rename request_queue slab to it reflects what it holds, and a fix for proper use of bdgrab/put. - A real fix for the split across stripe boundaries from Keith. We yanked a broken version of this from 4.4-rc final, this one works. - From Mike Krinkin, emit a trace message when we split. - From Wei Tang, two small cleanups, not explicitly clearing memory that is already cleared" * 'for-4.5/core' of git://git.kernel.dk/linux-block: block: use bd{grab,put}() instead of open-coding block: split bios to max possible length block: add call to split trace point blk-mq: Avoid memoryless numa node encoded in hctx numa_node blk-mq: Reuse hardware context cpumask for tags blk-mq: add a flags parameter to blk_mq_alloc_request Revert "blk-flush: Queue through IO scheduler when flush not required" block: clarify blk_add_timer() use case for blk-mq bio: use offset_in_page macro block: do not initialise statics to 0 or NULL block: do not initialise globals to 0 or NULL block: rename request_queue slab cache
2016-01-13null_blk: use sector_div instead of do_divArnd Bergmann
Dividing a sector_t number should be done using sector_div rather than do_div to optimize the 32-bit sector_t case, and with the latest do_div optimizations, we now get a compile-time warning for this: arch/arm/include/asm/div64.h:32:95: note: expected 'uint64_t * {aka long long unsigned int *}' but argument is of type 'sector_t * {aka long unsigned int *}' drivers/block/null_blk.c:521:81: warning: comparison of distinct pointer types lacks a cast This changes the newly added code to use sector_div. It is a simplified version of the original patch, as Linus Torvalds pointed out that we should not be using an expensive division function in the first place. This version was suggested by Matias Bjorling. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Matias Bjorling <m@bjorling.me> Fixes: b2b7e00148a2 ("null_blk: register as a LightNVM device") Signed-off-by: Jens Axboe <axboe@fb.com>
2016-01-12lightnvm: refactor end_io functions for syncMatias Bjørling
To implement sync I/O support within the LightNVM core, the end_io functions are refactored to take an end_io function pointer instead of testing for initialized media manager, followed by calling its end_io function. Sync I/O can then be implemented using a callback that signal I/O completion. This is similar to the logic found in blk_to_execute_io(). By implementing it this way, the underlying device I/Os submission logic is abstracted away from core, targets, and media managers. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-28null_blk: use async queue restart helperJens Axboe
If null_blk is run in NULL_IRQ_TIMER mode and with queue_mode NULL_Q_RQ, we need to restart the queue from the hrtimer interrupt. We can't directly invoke the request_fn from that context, so punt the queue run to async kblockd context. Tested-by: Rabin Vincent <rabin@rab.in> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-22null_blk: fix use-after-free errorMike Krinkin
blk_end_request_all may free request, so we need to save request_queue pointer before blk_end_request_all call. The problem was introduced in commit cf8ecc5a8455266f8d51 ("null_blk: guarantee device restart in all irq modes") and causes general protection fault with slab poisoning enabled. Fixes: cf8ecc5a8455266f8d51 ("null_blk: guarantee device restart in all irq modes") Signed-off-by: Mike Krinkin <krinkin.m.u@gmail.com> Reviewed-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-08null_blk: Fix error path in module initializationMinfei Huang
Module couldn't release resource properly during the initialization. To fix this issue, we will clean up the proper resource before returning. Signed-off-by: Minfei Huang <mnfhuang@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-07lightnvm: replace req queue with nvmdev for lldMatias Bjørling
In the case where a request queue is passed to the low lever lightnvm device drive integration, the device driver might pass its admin commands through another queue. Instead pass nvm_dev, and let the low level drive the appropriate queue. Reported-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-01blk-mq: add a flags parameter to blk_mq_alloc_requestChristoph Hellwig
We already have the reserved flag, and a nowait flag awkwardly encoded as a gfp_t. Add a real flags argument to make the scheme more extensible and allow for a nicer calling convention. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-01null_blk: change type of completion_nsec to unsigned longArianna Avanzini
This commit at least doubles the maximum value for completion_nsec. This helps in special cases where one wants/needs to emulate an extremely slow I/O (for example to spot bugs). Signed-off-by: Paolo Valente <paolo.valente@unimore.it> Signed-off-by: Arianna Avanzini <avanzini@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-01null_blk: guarantee device restart in all irq modesArianna Avanzini
In single-queue (block layer) mode,the function null_rq_prep_fn stops the device if alloc_cmd fails. Then, once stopped, the device must be restarted on the next command completion, so that the request(s) for which alloc_cmd failed can be requeued. Otherwise the device hangs. Unfortunately, device restart is currently performed only for delayed completions, i.e., in irqmode==2. This fact causes hangs, for the above reasons, with the other irqmodes in combination with single-queue block layer. This commits addresses this issue by making sure that, if stopped, the device is properly restarted for all irqmodes on completions. Signed-off-by: Paolo Valente <paolo.valente@unimore.it> Signed-off-by: Arianna AVanzini <avanzini@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-01null_blk: set a separate timer for each commandPaolo Valente
For the Timer IRQ mode (i.e., when command completions are delayed), there is one timer for each CPU. Each of these timers . has a completion queue associated with it, containing all the command completions to be executed when the timer fires; . is set, and a new completion-to-execute is inserted into its completion queue, every time the dispatch code for a new command happens to be executed on the CPU related to the timer. This implies that, if the dispatch of a new command happens to be executed on a CPU whose timer has already been set, but has not yet fired, then the timer is set again, to the completion time of the newly arrived command. When the timer eventually fires, all its queued completions are executed. This way of handling delayed command completions entails the following problem: if more than one command completion is inserted into the queue of a timer before the timer fires, then the expiration time for the timer is moved forward every time each of these completions is enqueued. As a consequence, only the last completion enqueued enjoys a correct execution time, while all previous completions are unjustly delayed until the last completion is executed (and at that time they are executed all together). Specifically, if all the above completions are enqueued almost at the same time, then the problem is negligible. On the opposite end, if every completion is enqueued a while after the previous completion was enqueued (in the extreme case, it is enqueued only right before the timer would have expired), then every enqueued completion, except for the last one, experiences an inflated delay, proportional to the number of completions enqueued after it. In the end, commands, and thus I/O requests, may be completed at an arbitrarily lower rate than the desired one. This commit addresses this issue by replacing per-CPU timers with per-command timers, i.e., by associating an individual timer with each command. Signed-off-by: Paolo Valente <paolo.valente@unimore.it> Signed-off-by: Arianna Avanzini <avanzini@google.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-19null_blk: do not del gendisk with lightnvmMatias Bjørling
The gendisk structure has not been initialized when using lightnvm. Make sure to not delete it upon exit. Also make sure that we use the appropriate disk_name at unregistration. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-19null_blk: use device addressing modeMatias Bjørling
The linear addressing mode was removed in 7386af2. Make null_blk instead expose the ppa format geometry and support the generic addressing mode. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-19null_blk: use ppa_cache poolMatias Bjørling
Instead of using a page pool, we can save memory by only allocating room for 64 entries for the ppa command. Introduce a ppa_cache to allocate only the required memory for the ppa list. Signed-off-by: Matias Bjørling <m@bjorling.me> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-16null_blk: register as a LightNVM deviceMatias Bjørling
Add support for registering as a LightNVM device. This allows us to evaluate the performance of the LightNVM subsystem. In /drivers/Makefile, LightNVM is moved above block device drivers to make sure that the LightNVM media managers have been initialized before drivers under /drivers/block are initialized. Signed-off-by: Matias Bjørling <m@bjorling.me> Fix by Jens Axboe to remove unneeded slab cache and the following memory leak. Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-07block: change ->make_request_fn() and users to return a queue cookieJens Axboe
No functional changes in this patch, but it prepares us for returning a more useful cookie related to the IO that was queued up. Signed-off-by: Jens Axboe <axboe@fb.com> Acked-by: Christoph Hellwig <hch@lst.de> Acked-by: Keith Busch <keith.busch@intel.com>
2015-10-01blk-mq: fix racy updates of rq->errorsChristoph Hellwig
blk_mq_complete_request may be a no-op if the request has already been completed by others means (e.g. a timeout or cancellation), but currently drivers have to set rq->errors before calling blk_mq_complete_request, which might leave us with the wrong error value. Add an error parameter to blk_mq_complete_request so that we can defer setting rq->errors until we known we won the race to complete the request. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Sagi Grimberg <sagig@mellanox.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-09-02null_blk: fix wrong capacity when bs is not 512 bytesMatias Bjørling
set_capacity() sets device's capacity using 512 bytes sectors. null_blk calculates the number of sectors by size / bs, which set_capacity is called with. This led to null_blk exposing the wrong number of sectors when bs is not 512 bytes. Signed-off-by: Matias Bjørling <m@bjorling.me> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-09-02null_blk: fix memory leak on cleanupMatias Bjørling
Driver was not freeing the memory allocated for internal nullb queues. This patch frees the memory during driver unload. Signed-off-by: Matias Bjørling <mb@lightnvm.io> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-09-02Merge branch 'for-4.3/core' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull core block updates from Jens Axboe: "This first core part of the block IO changes contains: - Cleanup of the bio IO error signaling from Christoph. We used to rely on the uptodate bit and passing around of an error, now we store the error in the bio itself. - Improvement of the above from myself, by shrinking the bio size down again to fit in two cachelines on x86-64. - Revert of the max_hw_sectors cap removal from a revision again, from Jeff Moyer. This caused performance regressions in various tests. Reinstate the limit, bump it to a more reasonable size instead. - Make /sys/block/<dev>/queue/discard_max_bytes writeable, by me. Most devices have huge trim limits, which can cause nasty latencies when deleting files. Enable the admin to configure the size down. We will look into having a more sane default instead of UINT_MAX sectors. - Improvement of the SGP gaps logic from Keith Busch. - Enable the block core to handle arbitrarily sized bios, which enables a nice simplification of bio_add_page() (which is an IO hot path). From Kent. - Improvements to the partition io stats accounting, making it faster. From Ming Lei. - Also from Ming Lei, a basic fixup for overflow of the sysfs pending file in blk-mq, as well as a fix for a blk-mq timeout race condition. - Ming Lin has been carrying Kents above mentioned patches forward for a while, and testing them. Ming also did a few fixes around that. - Sasha Levin found and fixed a use-after-free problem introduced by the bio->bi_error changes from Christoph. - Small blk cgroup cleanup from Viresh Kumar" * 'for-4.3/core' of git://git.kernel.dk/linux-block: (26 commits) blk: Fix bio_io_vec index when checking bvec gaps block: Replace SG_GAPS with new queue limits mask block: bump BLK_DEF_MAX_SECTORS to 2560 Revert "block: remove artifical max_hw_sectors cap" blk-mq: fix race between timeout and freeing request blk-mq: fix buffer overflow when reading sysfs file of 'pending' Documentation: update notes in biovecs about arbitrarily sized bios block: remove bio_get_nr_vecs() fs: use helper bio_add_page() instead of open coding on bi_io_vec block: kill merge_bvec_fn() completely md/raid5: get rid of bio_fits_rdev() md/raid5: split bio for chunk_aligned_read block: remove split code in blkdev_issue_{discard,write_same} btrfs: remove bio splitting and merge_bvec_fn() calls bcache: remove driver private bio splitting code block: simplify bio_add_page() block: make generic_make_request handle arbitrarily sized bios blk-cgroup: Drop unlikely before IS_ERR(_OR_NULL) block: don't access bio->bi_error after bio_put() block: shrink struct bio down to 2 cache lines again ...
2015-07-29block: add a bi_error field to struct bioChristoph Hellwig
Currently we have two different ways to signal an I/O error on a BIO: (1) by clearing the BIO_UPTODATE flag (2) by returning a Linux errno value to the bi_end_io callback The first one has the drawback of only communicating a single possible error (-EIO), and the second one has the drawback of not beeing persistent when bios are queued up, and are not passed along from child to parent bio in the ever more popular chaining scenario. Having both mechanisms available has the additional drawback of utterly confusing driver authors and introducing bugs where various I/O submitters only deal with one of them, and the others have to add boilerplate code to deal with both kinds of error returns. So add a new bi_error field to store an errno value directly in struct bio and remove the existing mechanisms to clean all this up. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-07-22null_blk: fix use-after-free problemMike Krinkin
end_cmd finishes request associated with nullb_cmd struct, so we should save pointer to request_queue in a local variable before calling end_cmd. The problem was causes general protection fault with slab poisoning enabled. Fixes: 8b70f45e2eb2 ("null_blk: restart request processing on completion handler") Tested-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Mike Krinkin <krinkin.m.u@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-07-01Merge tag 'modules-next-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull module updates from Rusty Russell: "Main excitement here is Peter Zijlstra's lockless rbtree optimization to speed module address lookup. He found some abusers of the module lock doing that too. A little bit of parameter work here too; including Dan Streetman's breaking up the big param mutex so writing a parameter can load another module (yeah, really). Unfortunately that broke the usual suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were appended too" * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits) modules: only use mod->param_lock if CONFIG_MODULES param: fix module param locks when !CONFIG_SYSFS. rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE() module: add per-module param_lock module: make perm const params: suppress unused variable error, warn once just in case code changes. modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'. kernel/module.c: avoid ifdefs for sig_enforce declaration kernel/workqueue.c: remove ifdefs over wq_power_efficient kernel/params.c: export param_ops_bool_enable_only kernel/params.c: generalize bool_enable_only kernel/module.c: use generic module param operaters for sig_enforce kernel/params: constify struct kernel_param_ops uses sysfs: tightened sysfs permission checks module: Rework module_addr_{min,max} module: Use __module_address() for module_address_lookup() module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING module: Optimize __module_address() using a latched RB-tree rbtree: Implement generic latch_tree seqlock: Introduce raw_read_seqcount_latch() ...
2015-06-01null_blk: restart request processing on completion handlerAkinobu Mita
When irqmode=2 (IRQ completion handler is timer) and queue_mode=1 (Block interface to use is rq), the completion handler should restart request handling for any pending requests on a queue because request processing stops when the number of commands are queued more than hw_queue_depth (null_rq_prep_fn returns BLKPREP_DEFER). Without this change, the following command cannot finish. # modprobe null_blk irqmode=2 queue_mode=1 hw_queue_depth=1 # fio --name=t --rw=read --size=1g --direct=1 \ --ioengine=libaio --iodepth=64 --filename=/dev/nullb0 Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Jens Axboe <axboe@fb.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-01null_blk: prevent timer handler running on a different CPU where startedAkinobu Mita
When irqmode=2 (IRQ completion handler is timer), timer handler should be called on the same CPU where the timer has been started. Since completion_queues are per-cpu and the completion handler only touches completion_queue for local CPU, we need to prevent the handler from running on a different CPU where the timer has been started. Otherwise, the IO cannot be completed until another completion handler is executed on that CPU. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Jens Axboe <axboe@fb.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-05-28kernel/params: constify struct kernel_param_ops usesLuis R. Rodriguez
Most code already uses consts for the struct kernel_param_ops, sweep the kernel for the last offending stragglers. Other than include/linux/moduleparam.h and kernel/params.c all other changes were generated with the following Coccinelle SmPL patch. Merge conflicts between trees can be handled with Coccinelle. In the future git could get Coccinelle merge support to deal with patch --> fail --> grammar --> Coccinelle --> new patch conflicts automatically for us on patches where the grammar is available and the patch is of high confidence. Consider this a feature request. Test compiled on x86_64 against: * allnoconfig * allmodconfig * allyesconfig @ const_found @ identifier ops; @@ const struct kernel_param_ops ops = { }; @ const_not_found depends on !const_found @ identifier ops; @@ -struct kernel_param_ops ops = { +const struct kernel_param_ops ops = { }; Generated-by: Coccinelle SmPL Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Junio C Hamano <gitster@pobox.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Kees Cook <keescook@chromium.org> Cc: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: cocci@systeme.lip6.fr Cc: linux-kernel@vger.kernel.org Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-16null_blk: suppress invalid partition infoJens Axboe
null_blk is partitionable, but it doesn't store any of the info. When it is loaded, you would normally see: [1226739.343608] nullb0: unknown partition table [1226739.343746] nullb1: unknown partition table which can confuse some people. Add the appropriate gendisk flag to suppress this info. Signed-off-by: Jens Axboe <axboe@fb.com>
2015-01-02block: fix checking return value of blk_mq_init_queueMing Lei
Check IS_ERR_OR_NULL(return value) instead of just return value. Signed-off-by: Ming Lei <ming.lei@canonical.com> Reduced to IS_ERR() by me, we never return NULL. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-11-26null_blk: boundary check queue_mode and irqmodeMatias Bjorling
When either queue_mode or irq_mode parameter is set outside its boundaries, the driver will not complete requests. This stalls driver initialization when partitions are probed. Fix by setting out of bound values to the parameters default. Signed-off-by: Matias Bjørling <m@bjorling.me> Updated by me to have the parse+check in just one function. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-11-18Merge branch 'master' into for-3.19/driversJens Axboe
2014-10-29blk-mq: add a 'list' parameter to ->queue_rq()Jens Axboe
Since we have the notion of a 'last' request in a chain, we can use this to have the hardware optimize the issuing of requests. Add a list_head parameter to queue_rq that the driver can use to temporarily store hw commands for issue when 'last' is true. If we are doing a chain of requests, pass in a NULL list for the first request to force issue of that immediately, then batch the remainder for deferred issue until the last request has been sent. Instead of adding yet another argument to the hot ->queue_rq path, encapsulate the passed arguments in a blk_mq_queue_data structure. This is passed as a constant, and has been tested as faster than passing 4 (or even 3) args through ->queue_rq. Update drivers for the new ->queue_rq() prototype. There are no functional changes in this patch for drivers - if they don't use the passed in list, then they will just queue requests individually like before. Signed-off-by: Jens Axboe <axboe@fb.com>
2014-10-22null_blk: Cleanup error recovery in null_add_dev()Jan Kara
When creation of queues fails in init_driver_queues(), we free the queues. But null_add_dev() doesn't test for this failure and continues with the setup leading to strange consequences, likely oops. Fix the problem by testing whether init_driver_queues() failed and do proper error cleanup. Coverity-id: 1148005 Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-10-18Merge branch 'for-3.18/drivers' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block layer driver update from Jens Axboe: "This is the block driver pull request for 3.18. Not a lot in there this round, and nothing earth shattering. - A round of drbd fixes from the linbit team, and an improvement in asender performance. - Removal of deprecated (and unused) IRQF_DISABLED flag in rsxx and hd from Michael Opdenacker. - Disable entropy collection from flash devices by default, from Mike Snitzer. - A small collection of xen blkfront/back fixes from Roger Pau Monné and Vitaly Kuznetsov" * 'for-3.18/drivers' of git://git.kernel.dk/linux-block: block: disable entropy contributions for nonrot devices xen, blkfront: factor out flush-related checks from do_blkif_request() xen-blkback: fix leak on grant map error path xen/blkback: unmap all persistent grants when frontend gets disconnected rsxx: Remove deprecated IRQF_DISABLED block: hd: remove deprecated IRQF_DISABLED drbd: use RB_DECLARE_CALLBACKS() to define augment callbacks drbd: compute the end before rb_insert_augmented() drbd: Add missing newline in resync progress display in /proc/drbd drbd: reduce lock contention in drbd_worker drbd: Improve asender performance drbd: Get rid of the WORK_PENDING macro drbd: Get rid of the __no_warn and __cond_lock macros drbd: Avoid inconsistent locking warning drbd: Remove superfluous newline from "resync_extents" debugfs entry. drbd: Use consistent names for all the bi_end_io callbacks drbd: Use better variable names
2014-10-04block: disable entropy contributions for nonrot devicesMike Snitzer
Clear QUEUE_FLAG_ADD_RANDOM in all block drivers that set QUEUE_FLAG_NONROT. Historically, all block devices have automatically made entropy contributions. But as previously stated in commit e2e1a148 ("block: add sysfs knob for turning off disk entropy contributions"): - On SSD disks, the completion times aren't as random as they are for rotational drives. So it's questionable whether they should contribute to the random pool in the first place. - Calling add_disk_randomness() has a lot of overhead. There are more reliable sources for randomness than non-rotational block devices. From a security perspective it is better to err on the side of caution than to allow entropy contributions from unreliable "random" sources. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>