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2024-06-24brd: add missing MODULE_DESCRIPTION() macroJeff Johnson1-0/+1
make allmodconfig && make W=1 C=1 reports: modpost: missing MODULE_DESCRIPTION() in drivers/block/brd.o Add the missing invocation of the MODULE_DESCRIPTION() macro. Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com> Link: https://lore.kernel.org/r/20240602-md-block-brd-v1-1-e71338e131b6@quicinc.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-06-19block: move the nowait flag to queue_limitsChristoph Hellwig1-2/+2
Move the nowait flag into the queue_limits feature field so that it can be set atomically with the queue frozen. Stacking drivers are simplified in that they now can simply set the flag, and blk_stack_limits will clear it when the features is not supported by any of the underlying devices. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20240617060532.127975-20-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-06-19block: move the synchronous flag to queue_limitsChristoph Hellwig1-1/+1
Move the synchronous flag into the queue_limits feature field so that it can be set atomically with the queue frozen. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20240617060532.127975-19-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-06-19block: move the nonrot flag to queue_limitsChristoph Hellwig1-2/+0
Move the nonrot flag into the queue_limits feature field so that it can be set atomically with the queue frozen. Use the chance to switch to defaulting to non-rotational and require the driver to opt into rotational, which matches the polarity of the sysfs interface. For the z2ram, ps3vram, 2x memstick, ubiblock and dcssblk the new rotational flag is not set as they clearly are not rotational despite this being a behavior change. There are some other drivers that unconditionally set the rotational flag to keep the existing behavior as they arguably can be used on rotational devices even if that is probably not their main use today (e.g. virtio_blk and drbd). The flag is automatically inherited in blk_stack_limits matching the existing behavior in dm and md. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20240617060532.127975-15-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-05-14brd: implement discard supportKeith Busch1-0/+26
The ramdisk memory utilization can only go up when data is written to new pages. Implement discard to provide the possibility to reduce memory usage for pages no longer in use. Aligned discards will free the associated pages, if any, and determinisitically return zeroed data until written again. Signed-off-by: Keith Busch <kbusch@kernel.org> Link: https://lore.kernel.org/r/20240429102308.147627-1-kbusch@meta.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-04-01brd: Remove use of page->indexMatthew Wilcox (Oracle)1-29/+11
This debugging check will become more costly in the future when we shrink struct page. It has not proven to be useful, so simply remove it. This lets us use __xa_insert instead of __xa_cmpxchg() as we no longer need to know about the page that is currently stored in the XArray. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Keith Busch <kbusch@kernel.org> Link: https://lore.kernel.org/r/20240315181212.2573753-1-willy@infradead.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-20brd: pass queue_limits to blk_mq_alloc_diskChristoph Hellwig1-10/+11
Pass the queue limits directly to blk_alloc_disk instead of setting them one at a time. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com> Link: https://lore.kernel.org/r/20240215071055.2201424-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-02-20block: pass a queue_limits argument to blk_alloc_diskChristoph Hellwig1-3/+4
Pass a queue_limits to blk_alloc_disk and apply it if non-NULL. This will allow allocating queues with valid queue limits instead of setting the values one at a time later. Also change blk_alloc_disk to return an ERR_PTR instead of just NULL which can't distinguish errors. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com> Link: https://lore.kernel.org/r/20240215071055.2201424-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-06-14brd: use cond_resched instead of cond_resched_rcuPankaj Raghav1-1/+1
The body of the loop is run without RCU lock held. Use the regular cond_resched() instead of cond_resched_rcu(). Fixes: 786bb0245881 ("brd: use XArray instead of radix-tree to index backing pages") Suggested-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Pankaj Raghav <p.raghav@samsung.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20230614133538.1279369-1-p.raghav@samsung.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-05-16brd: use XArray instead of radix-tree to index backing pagesPankaj Raghav1-69/+24
XArray was introduced to hold large array of pointers with a simple API. XArray API also provides array semantics which simplifies the way we store and access the backing pages, and the code becomes significantly easier to understand. No performance difference was noticed between the two implementation using fio with direct=1 [1]. [1] Performance in KIOPS: | radix-tree | XArray | Diff | | | write | 315 | 313 | -0.6% randwrite | 286 | 290 | +1.3% read | 330 | 335 | +1.5% randread | 309 | 312 | +0.9% Signed-off-by: Pankaj Raghav <p.raghav@samsung.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20230511121544.111648-1-p.raghav@samsung.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-04-25block/drivers: remove dead clear of random flagChaitanya Kulkarni1-1/+0
QUEUE_FLAG_ADD_RANDOM is not set before we clear it for "null_blk", "brd", "nbd", "zram", and "bcache" since by default we don't set "QUEUE_FLAG_ADD_RANDOM" to MQ ops. Remove dead clear of QUEUE_FLAG_ADD_RANDOM in above listed drivers. Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org> #zram Link: https://lore.kernel.org/r/20230424234628.45544-2-kch@nvidia.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-24Merge tag 'mm-stable-2023-02-20-13-37' of ↵Linus Torvalds1-14/+1
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Daniel Verkamp has contributed a memfd series ("mm/memfd: add F_SEAL_EXEC") which permits the setting of the memfd execute bit at memfd creation time, with the option of sealing the state of the X bit. - Peter Xu adds a patch series ("mm/hugetlb: Make huge_pte_offset() thread-safe for pmd unshare") which addresses a rare race condition related to PMD unsharing. - Several folioification patch serieses from Matthew Wilcox, Vishal Moola, Sidhartha Kumar and Lorenzo Stoakes - Johannes Weiner has a series ("mm: push down lock_page_memcg()") which does perform some memcg maintenance and cleanup work. - SeongJae Park has added DAMOS filtering to DAMON, with the series "mm/damon/core: implement damos filter". These filters provide users with finer-grained control over DAMOS's actions. SeongJae has also done some DAMON cleanup work. - Kairui Song adds a series ("Clean up and fixes for swap"). - Vernon Yang contributed the series "Clean up and refinement for maple tree". - Yu Zhao has contributed the "mm: multi-gen LRU: memcg LRU" series. It adds to MGLRU an LRU of memcgs, to improve the scalability of global reclaim. - David Hildenbrand has added some userfaultfd cleanup work in the series "mm: uffd-wp + change_protection() cleanups". - Christoph Hellwig has removed the generic_writepages() library function in the series "remove generic_writepages". - Baolin Wang has performed some maintenance on the compaction code in his series "Some small improvements for compaction". - Sidhartha Kumar is doing some maintenance work on struct page in his series "Get rid of tail page fields". - David Hildenbrand contributed some cleanup, bugfixing and generalization of pte management and of pte debugging in his series "mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE on all architectures with swap PTEs". - Mel Gorman and Neil Brown have removed the __GFP_ATOMIC allocation flag in the series "Discard __GFP_ATOMIC". - Sergey Senozhatsky has improved zsmalloc's memory utilization with his series "zsmalloc: make zspage chain size configurable". - Joey Gouly has added prctl() support for prohibiting the creation of writeable+executable mappings. The previous BPF-based approach had shortcomings. See "mm: In-kernel support for memory-deny-write-execute (MDWE)". - Waiman Long did some kmemleak cleanup and bugfixing in the series "mm/kmemleak: Simplify kmemleak_cond_resched() & fix UAF". - T.J. Alumbaugh has contributed some MGLRU cleanup work in his series "mm: multi-gen LRU: improve". - Jiaqi Yan has provided some enhancements to our memory error statistics reporting, mainly by presenting the statistics on a per-node basis. See the series "Introduce per NUMA node memory error statistics". - Mel Gorman has a second and hopefully final shot at fixing a CPU-hog regression in compaction via his series "Fix excessive CPU usage during compaction". - Christoph Hellwig does some vmalloc maintenance work in the series "cleanup vfree and vunmap". - Christoph Hellwig has removed block_device_operations.rw_page() in ths series "remove ->rw_page". - We get some maple_tree improvements and cleanups in Liam Howlett's series "VMA tree type safety and remove __vma_adjust()". - Suren Baghdasaryan has done some work on the maintainability of our vm_flags handling in the series "introduce vm_flags modifier functions". - Some pagemap cleanup and generalization work in Mike Rapoport's series "mm, arch: add generic implementation of pfn_valid() for FLATMEM" and "fixups for generic implementation of pfn_valid()" - Baoquan He has done some work to make /proc/vmallocinfo and /proc/kcore better represent the real state of things in his series "mm/vmalloc.c: allow vread() to read out vm_map_ram areas". - Jason Gunthorpe rationalized the GUP system's interface to the rest of the kernel in the series "Simplify the external interface for GUP". - SeongJae Park wishes to migrate people from DAMON's debugfs interface over to its sysfs interface. To support this, we'll temporarily be printing warnings when people use the debugfs interface. See the series "mm/damon: deprecate DAMON debugfs interface". - Andrey Konovalov provided the accurately named "lib/stackdepot: fixes and clean-ups" series. - Huang Ying has provided a dramatic reduction in migration's TLB flush IPI rates with the series "migrate_pages(): batch TLB flushing". - Arnd Bergmann has some objtool fixups in "objtool warning fixes". * tag 'mm-stable-2023-02-20-13-37' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (505 commits) include/linux/migrate.h: remove unneeded externs mm/memory_hotplug: cleanup return value handing in do_migrate_range() mm/uffd: fix comment in handling pte markers mm: change to return bool for isolate_movable_page() mm: hugetlb: change to return bool for isolate_hugetlb() mm: change to return bool for isolate_lru_page() mm: change to return bool for folio_isolate_lru() objtool: add UACCESS exceptions for __tsan_volatile_read/write kmsan: disable ftrace in kmsan core code kasan: mark addr_has_metadata __always_inline mm: memcontrol: rename memcg_kmem_enabled() sh: initialize max_mapnr m68k/nommu: add missing definition of ARCH_PFN_OFFSET mm: percpu: fix incorrect size in pcpu_obj_full_size() maple_tree: reduce stack usage with gcc-9 and earlier mm: page_alloc: call panic() when memoryless node allocation fails mm: multi-gen LRU: avoid futile retries migrate_pages: move THP/hugetlb migration support check to simplify code migrate_pages: batch flushing TLB migrate_pages: share more code between _unmap and _move ...
2023-02-17brd: use radix_tree_maybe_preload instead of radix_tree_preloadPankaj Raghav1-1/+1
Unconditionally calling radix_tree_preload_end() results in a OOPS message as the preload is only conditionally called for gfpflags_allow_blocking(). [ 20.267323] BUG: using smp_processor_id() in preemptible [00000000] code: fio/416 [ 20.267837] caller is brd_insert_page.part.0+0xbe/0x190 [brd] [ 20.269436] Call Trace: [ 20.269598] <TASK> [ 20.269742] dump_stack_lvl+0x32/0x50 [ 20.269982] check_preemption_disabled+0xd1/0xe0 [ 20.270289] brd_insert_page.part.0+0xbe/0x190 [brd] [ 20.270664] brd_submit_bio+0x33f/0xf40 [brd] Use radix_tree_maybe_preload() which does preload only if gfpflags_allow_blocking() is true but also takes the lock. Therefore, unconditionally calling radix_tree_preload_end() should not create any issues and the message disappears. Fixes: 6ded703c56c2 ("brd: check for REQ_NOWAIT and set correct page allocation mask") Signed-off-by: Pankaj Raghav <p.raghav@samsung.com> Link: https://lore.kernel.org/r/20230217121442.33914-1-p.raghav@samsung.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-16brd: mark as nowait compatibleJens Axboe1-0/+1
By default, non-mq drivers do not support nowait. This causes io_uring to use a slower path as the driver cannot be trust not to block. brd can safely set the nowait flag, as worst case all it does is a NOIO allocation. For io_uring, this makes a substantial difference. Before: submitter=0, tid=453, file=/dev/ram0, node=-1 polled=0, fixedbufs=1/0, register_files=1, buffered=0, QD=128 Engine=io_uring, sq_ring=128, cq_ring=128 IOPS=440.03K, BW=1718MiB/s, IOS/call=32/31 IOPS=428.96K, BW=1675MiB/s, IOS/call=32/32 IOPS=442.59K, BW=1728MiB/s, IOS/call=32/31 IOPS=419.65K, BW=1639MiB/s, IOS/call=32/32 IOPS=426.82K, BW=1667MiB/s, IOS/call=32/31 and after: submitter=0, tid=354, file=/dev/ram0, node=-1 polled=0, fixedbufs=1/0, register_files=1, buffered=0, QD=128 Engine=io_uring, sq_ring=128, cq_ring=128 IOPS=3.37M, BW=13.15GiB/s, IOS/call=32/31 IOPS=3.45M, BW=13.46GiB/s, IOS/call=32/31 IOPS=3.43M, BW=13.42GiB/s, IOS/call=32/32 IOPS=3.43M, BW=13.39GiB/s, IOS/call=32/31 IOPS=3.43M, BW=13.38GiB/s, IOS/call=32/31 or about an 8x in difference. Now that brd is prepared to deal with REQ_NOWAIT reads/writes, mark it as supporting that. Cc: stable@vger.kernel.org # 5.10+ Link: https://lore.kernel.org/linux-block/20230203103005.31290-1-p.raghav@samsung.com/ Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-16brd: check for REQ_NOWAIT and set correct page allocation maskJens Axboe1-20/+28
If REQ_NOWAIT is set, then do a non-blocking allocation if the operation is a write and we need to insert a new page. Currently REQ_NOWAIT cannot be set as the queue isn't marked as supporting nowait, this change is in preparation for allowing that. radix_tree_preload() warns on attempting to call it with an allocation mask that doesn't allow blocking. While that warning could arguably be removed, we need to handle radix insertion failures anyway as they are more likely if we cannot block to get memory. Remove legacy BUG_ON()'s and turn them into proper errors instead, one for the allocation failure and one for finding a page that doesn't match the correct index. Cc: stable@vger.kernel.org # 5.10+ Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-16brd: return 0/-error from brd_insert_page()Jens Axboe1-14/+12
It currently returns a page, but callers just check for NULL/page to gauge success. Clean this up and return the appropriate error directly instead. Cc: stable@vger.kernel.org # 5.10+ Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2023-02-03block: remove ->rw_pageChristoph Hellwig1-14/+1
The ->rw_page method is a special purpose bypass of the usual bio handling path that is limited to single-page reads and writes and synchronous which causes a lot of extra code in the drivers, callers and the block layer. The only remaining user is the MM swap code. Switch that swap code to simply submit a single-vec on-stack bio an synchronously wait on it based on a newly added QUEUE_FLAG_SYNCHRONOUS flag set by the drivers that currently implement ->rw_page instead. While this touches one extra cache line and executes extra code, it simplifies the block layer and drivers and ensures that all feastures are properly supported by all drivers, e.g. right now ->rw_page bypassed cgroup writeback entirely. [akpm@linux-foundation.org: fix comment typo, per Dan] Link: https://lkml.kernel.org/r/20230125133436.447864-8-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Keith Busch <kbusch@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org> Cc: Vishal Verma <vishal.l.verma@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-22block: move from strlcpy with unused retval to strscpyWolfram Sang1-1/+1
Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> Acked-by: Geoff Levand <geoff@infradead.org> Link: https://lore.kernel.org/r/20220818205958.6552-1-wsa+renesas@sang-engineering.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-14block/brd: Use the enum req_op typeBart Van Assche1-1/+1
Improve static type checking by using the enum req_op type for a function argument that represents a request operation. Cc: Christoph Hellwig <hch@lst.de> Cc: Ming Lei <ming.lei@redhat.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20220714180729.1065367-13-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-14block: Change the type of the last .rw_page() argumentBart Van Assche1-1/+1
All .rw_page() callers pass an enum req_op value as last argument. Make this explicit by changing the type of the last argument into enum req_op. See also commit 3f289dcb4b26 ("block: make bdev_ops->rw_page() take a REQ_OP instead of bool"). Cc: Tejun Heo <tj@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Hannes Reinecke <hare@suse.de> Cc: Damien Le Moal <damien.lemoal@wdc.com> Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Bart Van Assche <bvanassche@acm.org> Link: https://lore.kernel.org/r/20220714180729.1065367-4-bvanassche@acm.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-06-28block: remove blk_cleanup_diskChristoph Hellwig1-2/+2
blk_cleanup_disk is nothing but a trivial wrapper for put_disk now, so remove it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20220619060552.1850436-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-01-17brd: remove brd_devices_mutex mutexTetsuo Handa1-43/+30
If brd_alloc() from brd_probe() is called before brd_alloc() from brd_init() is called, module loading will fail with -EEXIST error. To close this race, call __register_blkdev() just before leaving brd_init(). Then, we can remove brd_devices_mutex mutex, for brd_device list will no longer be accessed concurrently. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/6b074af7-c165-4fab-b7da-8270a4f6f6cd@i-love.sakura.ne.jp Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29block: remove GENHD_FL_EXT_DEVTChristoph Hellwig1-1/+0
All modern drivers can support extra partitions using the extended dev_t. In fact except for the ioctl method drivers never even see partitions in normal operation. So remove the GENHD_FL_EXT_DEVT and allow extra partitions for all block devices that do support partitions, and require those that do not support partitions to explicit disallow them using GENHD_FL_NO_PART. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/20211122130625.1136848-12-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-30block/brd: add error handling support for add_disk()Luis Chamberlain1-2/+7
We never checked for errors on add_disk() as this function returned void. Now that this is fixed, use the shiny new error handling. Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Link: https://lore.kernel.org/r/20211015235219.2191207-2-mcgrof@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18block: switch polling to be bio basedChristoph Hellwig1-7/+5
Replace the blk_poll interface that requires the caller to keep a queue and cookie from the submissions with polling based on the bio. Polling for the bio itself leads to a few advantages: - the cookie construction can made entirely private in blk-mq.c - the caller does not need to remember the request_queue and cookie separately and thus sidesteps their lifetime issues - keeping the device and the cookie inside the bio allows to trivially support polling BIOs remapping by stacking drivers - a lot of code to propagate the cookie back up the submission path can be removed entirely. Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Mark Wunderlich <mark.wunderlich@intel.com> Link: https://lore.kernel.org/r/20211012111226.760968-15-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-17brd: reduce the brd_devices_mutex scopeTetsuo Handa1-22/+22
As with commit 8b52d8be86d72308 ("loop: reorder loop_exit"), unregister_blkdev() needs to be called first in order to avoid calling brd_alloc() from brd_probe() after brd_del_one() from brd_exit(). Then, we can avoid holding global mutex during add_disk()/del_gendisk() as with commit 1c500ad706383f1a ("loop: reduce the loop_ctl_mutex scope"). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reviewed-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/r/e205f13d-18ff-a49c-0988-7de6ea5ff823@i-love.sakura.ne.jp Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-12block: move some macros to blkdev.hGuoqing Jiang1-3/+0
Move them (PAGE_SECTORS_SHIFT, PAGE_SECTORS and SECTOR_MASK) to the generic header file to remove redundancy. Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn> Link: https://lore.kernel.org/r/20210721025315.1729118-1-guoqing.jiang@linux.dev Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-01brd: convert to blk_alloc_disk/blk_cleanup_diskChristoph Hellwig1-61/+33
Convert the brd driver to use the blk_alloc_disk and blk_cleanup_disk helpers to simplify gendisk and request_queue allocation. This also allows to remove the request_queue pointer in struct request_queue, and to simplify the initialization as blk_cleanup_disk can be called on any disk returned from blk_alloc_disk. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Link: https://lore.kernel.org/r/20210521055116.1053587-7-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-07include: remove pagemap.h from blkdev.hMatthew Wilcox (Oracle)1-0/+1
My UEK-derived config has 1030 files depending on pagemap.h before this change. Afterwards, just 326 files need to be rebuilt when I touch pagemap.h. I think blkdev.h is probably included too widely, but untangling that dependency is harder and this solves my problem. x86 allmodconfig builds, but there may be implicit include problems on other architectures. Link: https://lkml.kernel.org/r/20210309195747.283796-1-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Dan Williams <dan.j.williams@intel.com> [nvdimm] Acked-by: Jens Axboe <axboe@kernel.dk> [block] Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Coly Li <colyli@suse.de> [bcache] Acked-by: Martin K. Petersen <martin.petersen@oracle.com> [scsi] Reviewed-by: William Kucharski <william.kucharski@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-21brd: expose number of allocated pages in debugfsCalvin Owens1-1/+18
While the maximum size of each ramdisk is defined either as a module parameter, or compile time default, it's impossible to know how many pages have currently been allocated by each ram%d device, since they're allocated when used and never freed. This patch creates a new directory at this location: /sys/kernel/debug/ramdisk_pages/ which will contain a file named "ram%d" for each instantiated ramdisk on the system. The file is read-only, and read() will output the number of pages currently held by that ramdisk. We lose track how much memory a ramdisk is using as pages once used are simply recycled but never freed. In instances where we exhaust the size of the ramdisk with a file that exceeds it, encounter ENOSPC and delete the file for mitigation; df would show decrease in used and increase in available blocks but the since we have touched all pages, the memory footprint of the ramdisk does not reflect the blocks used/available count ... [root@localhost ~]# mkfs.ext2 /dev/ram15 mke2fs 1.45.6 (20-Mar-2020) Creating filesystem with 4096 1k blocks and 1024 inodes [root@localhost ~]# mount /dev/ram15 /mnt/ram15/ [root@localhost ~]# cat /sys/kernel/debug/ramdisk_pages/ram15 58 [root@kerneltest008.06.prn3 ~]# df /dev/ram15 Filesystem 1K-blocks Used Available Use% Mounted on /dev/ram15 3963 31 3728 1% /mnt/ram15 [root@kerneltest008.06.prn3 ~]# dd if=/dev/urandom of=/mnt/ram15/test2 bs=1M count=5 dd: error writing '/mnt/ram15/test2': No space left on device 4+0 records in 3+0 records out 4005888 bytes (4.0 MB, 3.8 MiB) copied, 0.0446614 s, 89.7 MB/s [root@kerneltest008.06.prn3 ~]# df /mnt/ram15/ Filesystem 1K-blocks Used Available Use% Mounted on /dev/ram15 3963 3960 0 100% /mnt/ram15 [root@kerneltest008.06.prn3 ~]# cat /sys/kernel/debug/ramdisk_pages/ram15 1024 [root@kerneltest008.06.prn3 ~]# rm /mnt/ram15/test2 rm: remove regular file '/mnt/ram15/test2'? y [root@kerneltest008.06.prn3 /var]# df /dev/ram15 Filesystem 1K-blocks Used Available Use% Mounted on /dev/ram15 3963 31 3728 1% /mnt/ram15 # Acutal memory footprint [root@kerneltest008.06.prn3 /var]# cat /sys/kernel/debug/ramdisk_pages/ram15 1024 ... This debugfs counter will always reveal the accurate number of permanently allocated pages to the ramdisk. Signed-off-by: Calvin Owens <calvinowens@fb.com> [cleaned up the !CONFIG_DEBUG_FS case and API changes for HEAD] Signed-off-by: Kyle McMartin <jkkm@fb.com> [rebased] Signed-off-by: Saravanan D <saravanand@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-25block: store a block_device pointer in struct bioChristoph Hellwig1-1/+1
Replace the gendisk pointer in struct bio with a pointer to the newly improved struct block device. From that the gendisk can be trivially accessed with an extra indirection, but it also allows to directly look up all information related to partition remapping. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-25brd: remove the end of device check in brd_do_bvecChristoph Hellwig1-5/+1
The block layer already checks for this conditions in bio_check_eod before calling the driver. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-11-16brd: use __register_blkdev to allocate devices on demandChristoph Hellwig1-28/+11
Use the simpler mechanism attached to major_name to allocate a brd device when a currently unregistered minor is accessed. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-24bdi: remove BDI_CAP_SYNCHRONOUS_IOChristoph Hellwig1-1/+0
BDI_CAP_SYNCHRONOUS_IO is only checked in the swap code, and used to decided if ->rw_page can be used on a block device. Just check up for the method instead. The only complication is that zram needs a second set of block_device_operations as it can switch between modes that actually support ->rw_page and those who don't. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-07-01block: move ->make_request_fn to struct block_device_operationsChristoph Hellwig1-2/+3
The make_request_fn is a little weird in that it sits directly in struct request_queue instead of an operation vector. Replace it with a block_device_operations method called submit_bio (which describes much better what it does). Also remove the request_queue argument to it, as the queue can be derived pretty trivially from the bio. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-03-27block: simplify queue allocationChristoph Hellwig1-3/+1
Current make_request based drivers use either blk_alloc_queue_node or blk_alloc_queue to allocate a queue, and then set up the make_request_fn function pointer and a few parameters using the blk_queue_make_request helper. Simplify this by passing the make_request pointer to blk_alloc_queue, and while at it merge the _node variant into the main helper by always passing a node_id, and remove the superfluous gfp_mask parameter. A lower-level __blk_alloc_queue is kept for the blk-mq case. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-02-04brd: check and limit max_part parZhiqiang Liu1-2/+20
In brd_init func, rd_nr num of brd_device are firstly allocated and add in brd_devices, then brd_devices are traversed to add each brd_device by calling add_disk func. When allocating brd_device, the disk->first_minor is set to i * max_part, if rd_nr * max_part is larger than MINORMASK, two different brd_device may have the same devt, then only one of them can be successfully added. when rmmod brd.ko, it will cause oops when calling brd_exit. Follow those steps: # modprobe brd rd_nr=3 rd_size=102400 max_part=1048576 # rmmod brd then, the oops will appear. Oops log: [ 726.613722] Call trace: [ 726.614175] kernfs_find_ns+0x24/0x130 [ 726.614852] kernfs_find_and_get_ns+0x44/0x68 [ 726.615749] sysfs_remove_group+0x38/0xb0 [ 726.616520] blk_trace_remove_sysfs+0x1c/0x28 [ 726.617320] blk_unregister_queue+0x98/0x100 [ 726.618105] del_gendisk+0x144/0x2b8 [ 726.618759] brd_exit+0x68/0x560 [brd] [ 726.619501] __arm64_sys_delete_module+0x19c/0x2a0 [ 726.620384] el0_svc_common+0x78/0x130 [ 726.621057] el0_svc_handler+0x38/0x78 [ 726.621738] el0_svc+0x8/0xc [ 726.622259] Code: aa0203f6 aa0103f7 aa1e03e0 d503201f (7940e260) Here, we add brd_check_and_reset_par func to check and limit max_part par. -- V5->V6: - remove useless code V4->V5:(suggested by Ming Lei) - make sure max_part is not larger than DISK_MAX_PARTS V3->V4:(suggested by Ming Lei) - remove useless change - add one limit of max_part V2->V3: (suggested by Ming Lei) - clear .minors when running out of consecutive minor space in brd_alloc - remove limit of rd_nr V1->V2: - add more checks in brd_check_par_valid as suggested by Ming Lei. Signed-off-by: Zhiqiang Liu <liuzhiqiang26@huawei.com> Reviewed-by: Bob Liu <bob.liu@oracle.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-12-04brd: warn on un-aligned bufferMing Lei1-0/+4
Queue dma alignment limit requires users(fs, target, ...) of block layer to pass aligned buffer. So far brd doesn't support un-aligned buffer, even though it is easy to support it. However, given brd is often used for debug purpose, and there are other drivers which can't support un-aligned buffer too. So add warning so that brd users know what to fix. Reported-by: Stephen Rust <srust@blockbridge.com> Cc: Stephen Rust <srust@blockbridge.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-12-04brd: remove max_hw_sectors queue limitMing Lei1-1/+0
Now we depend on blk_queue_split() to respect most of queue limit (the only one exception could be dma alignment), however blk_queue_split() isn't used for brd, so this limit isn't respected since v4.3. Also max_hw_sectors limit doesn't play a big role for brd, which is added since brd is added to tree for unknown reason. So remove it. Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-05-21treewide: Add SPDX license identifier for more missed filesThomas Gleixner1-0/+1
Add SPDX license identifiers to all files which: - Have no license information of any form - Have MODULE_LICENCE("GPL*") inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-09brd: add cond_resched to brd_free_pagesMikulas Patocka1-0/+6
The loop that frees all the pages can take unbounded amount of time, so add cond_resched() to it. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-22brd: re-enable __GFP_HIGHMEM in brd_insert_page()Hou Tao1-6/+1
__GFP_HIGHMEM is disabled if dax is enabled on brd, however dax support for brd has been removed since commit (7a862fbbdec6 "brd: remove dax support"), so restore __GFP_HIGHMEM in brd_insert_page(). Also remove the no longer applicable comments about DAX and highmem. Cc: stable@vger.kernel.org Fixes: 7a862fbbdec6 ("brd: remove dax support") Signed-off-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-02block: brd: associate with queue until adding diskMing Lei1-5/+11
brd_free() may be called in failure path on one brd instance which disk isn't added yet, so release handler of gendisk may free the associated request_queue early and causes the following use-after-free[1]. This patch fixes this issue by associating gendisk with request_queue just before adding disk. [1] KASAN: use-after-free Read in del_timer_syncNon-volatile memory driver v1.3 Linux agpgart interface v0.103 [drm] Initialized vgem 1.0.0 20120112 for virtual device on minor 0 usbcore: registered new interface driver udl ================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x36d9/0x4c20 kernel/locking/lockdep.c:3218 Read of size 8 at addr ffff8801d1b6b540 by task swapper/0/1 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.0+ #88 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x244/0x39d lib/dump_stack.c:113 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 __lock_acquire+0x36d9/0x4c20 kernel/locking/lockdep.c:3218 lock_acquire+0x1ed/0x520 kernel/locking/lockdep.c:3844 del_timer_sync+0xb7/0x270 kernel/time/timer.c:1283 blk_cleanup_queue+0x413/0x710 block/blk-core.c:809 brd_free+0x5d/0x71 drivers/block/brd.c:422 brd_init+0x2eb/0x393 drivers/block/brd.c:518 do_one_initcall+0x145/0x957 init/main.c:890 do_initcall_level init/main.c:958 [inline] do_initcalls init/main.c:966 [inline] do_basic_setup init/main.c:984 [inline] kernel_init_freeable+0x5c6/0x6b9 init/main.c:1148 kernel_init+0x11/0x1ae init/main.c:1068 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:350 Reported-by: syzbot+3701447012fe951dabb2@syzkaller.appspotmail.com Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-18block: make bdev_ops->rw_page() take a REQ_OP instead of boolTejun Heo1-7/+7
c11f0c0b5bb9 ("block/mm: make bdev_ops->rw_page() take a bool for read/write") replaced @op with boolean @is_write, which limited the amount of information going into ->rw_page() and more importantly page_endio(), which removed the need to expose block internals to mm. Unfortunately, we want to track discards separately and @is_write isn't enough information. This patch updates bdev_ops->rw_page() to take REQ_OP instead but leaves page_endio() to take bool @is_write. This allows the block part of operations to have enough information while not leaking it to mm. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Mike Christie <mchristi@redhat.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-24block drivers/block: Use octal not symbolic permissionsJoe Perches1-3/+3
Convert the S_<FOO> symbolic permissions to their octal equivalents as using octal and not symbolic permissions is preferred by many as more readable. see: https://lkml.org/lkml/2016/8/2/1945 Done with automated conversion via: $ ./scripts/checkpatch.pl -f --types=SYMBOLIC_PERMS --fix-inplace <files...> Miscellanea: o Wrapped modified multi-line calls to a single line where appropriate o Realign modified multi-line calls to open parenthesis Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-09brd: Mark as non-rotationalSeongJae Park1-0/+4
This commit sets QUEUE_FLAG_NONROT and clears up QUEUE_FLAG_ADD_RANDOM to mark the ramdisks as non-rotational device. Signed-off-by: SeongJae Park <sj38.park@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-03-17block: Move SECTOR_SIZE and SECTOR_SHIFT definitions into <linux/blkdev.h>Bart Van Assche1-1/+0
It happens often while I'm preparing a patch for a block driver that I'm wondering: is a definition of SECTOR_SIZE and/or SECTOR_SHIFT available for this driver? Do I have to introduce definitions of these constants before I can use these constants? To avoid this confusion, move the existing definitions of SECTOR_SIZE and SECTOR_SHIFT into the <linux/blkdev.h> header file such that these become available for all block drivers. Make the SECTOR_SIZE definition in the uapi msdos_fs.h header file conditional to avoid that including that header file after <linux/blkdev.h> causes the compiler to complain about a SECTOR_SIZE redefinition. Note: the SECTOR_SIZE / SECTOR_SHIFT / SECTOR_BITS definitions have not been removed from uapi header files nor from NAND drivers in which these constants are used for another purpose than converting block layer offsets and sizes into a number of sectors. Cc: David S. Miller <davem@davemloft.net> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-02-26genhd: Rename get_disk() to get_disk_and_module()Jan Kara1-1/+1
Rename get_disk() to get_disk_and_module() to make sure what the function does. It's not a great name but at least it is now clear that put_disk() is not it's counterpart. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-11-17Merge tag 'libnvdimm-for-4.15' of ↵Linus Torvalds1-65/+0
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm and dax updates from Dan Williams: "Save for a few late fixes, all of these commits have shipped in -next releases since before the merge window opened, and 0day has given a build success notification. The ext4 touches came from Jan, and the xfs touches have Darrick's reviewed-by. An xfstest for the MAP_SYNC feature has been through a few round of reviews and is on track to be merged. - Introduce MAP_SYNC and MAP_SHARED_VALIDATE, a mechanism to enable 'userspace flush' of persistent memory updates via filesystem-dax mappings. It arranges for any filesystem metadata updates that may be required to satisfy a write fault to also be flushed ("on disk") before the kernel returns to userspace from the fault handler. Effectively every write-fault that dirties metadata completes an fsync() before returning from the fault handler. The new MAP_SHARED_VALIDATE mapping type guarantees that the MAP_SYNC flag is validated as supported by the filesystem's ->mmap() file operation. - Add support for the standard ACPI 6.2 label access methods that replace the NVDIMM_FAMILY_INTEL (vendor specific) label methods. This enables interoperability with environments that only implement the standardized methods. - Add support for the ACPI 6.2 NVDIMM media error injection methods. - Add support for the NVDIMM_FAMILY_INTEL v1.6 DIMM commands for latch last shutdown status, firmware update, SMART error injection, and SMART alarm threshold control. - Cleanup physical address information disclosures to be root-only. - Fix revalidation of the DIMM "locked label area" status to support dynamic unlock of the label area. - Expand unit test infrastructure to mock the ACPI 6.2 Translate SPA (system-physical-address) command and error injection commands. Acknowledgements that came after the commits were pushed to -next: - 957ac8c421ad ("dax: fix PMD faults on zero-length files"): Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> - a39e596baa07 ("xfs: support for synchronous DAX faults") and 7b565c9f965b ("xfs: Implement xfs_filemap_pfn_mkwrite() using __xfs_filemap_fault()") Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>" * tag 'libnvdimm-for-4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (49 commits) acpi, nfit: add 'Enable Latch System Shutdown Status' command support dax: fix general protection fault in dax_alloc_inode dax: fix PMD faults on zero-length files dax: stop requiring a live device for dax_flush() brd: remove dax support dax: quiet bdev_dax_supported() fs, dax: unify IOMAP_F_DIRTY read vs write handling policy in the dax core tools/testing/nvdimm: unit test clear-error commands acpi, nfit: validate commands against the device type tools/testing/nvdimm: stricter bounds checking for error injection commands xfs: support for synchronous DAX faults xfs: Implement xfs_filemap_pfn_mkwrite() using __xfs_filemap_fault() ext4: Support for synchronous DAX faults ext4: Simplify error handling in ext4_dax_huge_fault() dax: Implement dax_finish_sync_fault() dax, iomap: Add support for synchronous faults mm: Define MAP_SYNC and VM_SYNC flags dax: Allow tuning whether dax_insert_mapping_entry() dirties entry dax: Allow dax_iomap_fault() to return pfn dax: Fix comment describing dax_iomap_fault() ...
2017-11-16bdi: introduce BDI_CAP_SYNCHRONOUS_IOMinchan Kim1-0/+2
As discussed at https://lkml.kernel.org/r/<20170728165604.10455-1-ross.zwisler@linux.intel.com> someday we will remove rw_page(). If so, we need something to detect such super-fast storage on which synchronous IO operations like the current rw_page are always a win. Introduces BDI_CAP_SYNCHRONOUS_IO to indicate such devices. With it, we could use various optimization techniques. Link: http://lkml.kernel.org/r/1505886205-9671-3-git-send-email-minchan@kernel.org Signed-off-by: Minchan Kim <minchan@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ilya Dryomov <idryomov@gmail.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Huang Ying <ying.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>