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* block: add a bvec_set_virt helperChristoph Hellwig2023-02-031-0/+12
| | | | | | | | | | | A small wrapper around bvec_set_page for callers that have a virtual address. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20230203150634.3199647-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: add a bvec_set_folio helperChristoph Hellwig2023-02-031-0/+13
| | | | | | | | | | | | A smaller wrapper around bvec_set_page that takes a folio instead. There are only two potential users for this in the tree, but the number will grow in the future. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20230203150634.3199647-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: factor out a bvec_set_page helperChristoph Hellwig2023-02-031-0/+15
| | | | | | | | | | | Add a helper to initialize a bvec based of a page pointer. This will help removing various open code bvec initializations. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Link: https://lore.kernel.org/r/20230203150634.3199647-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: Remove mm.h from bvec.hMatthew Wilcox2023-01-311-1/+0
| | | | | | | | | | This was originally added for the definition of nth_page(), but we no longer use nth_page() in this header, so we can drop the heavyweight mm.h now. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Link: https://lore.kernel.org/r/20230131050132.2627124-1-willy@infradead.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: define 'struct bvec_iter' as packedMing Lei2021-10-181-1/+1
| | | | | | | | | | | | | | | | | | | 'struct bvec_iter' is embedded into 'struct bio', define it as packed so that we can get one extra 4bytes for other uses without expanding bio. 'struct bvec_iter' is often allocated on stack, so making it packed doesn't affect performance. Also I have run io_uring on both nvme/null_blk, and not observe performance effect in this way. Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Mark Wunderlich <mark.wunderlich@intel.com> Link: https://lore.kernel.org/r/20211012111226.760968-14-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* bvec: add a bvec_virt helperChristoph Hellwig2021-08-161-0/+12
| | | | | | | | | | | Add a helper to get the virtual address for a bvec. This avoids that all callers need to know about the page + offset representation. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@kernel.org> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20210804095634.460779-2-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* bvec: add memcpy_{from,to}_bvec and memzero_bvec helperChristoph Hellwig2021-08-021-0/+33
| | | | | | | | | | | Add helpers to perform common memory operation on a bvec. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/20210727055646.118787-5-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* bvec: add a bvec_kmap_local helperChristoph Hellwig2021-08-021-0/+13
| | | | | | | | | | | | | Add a helper to call kmap_local_page on a bvec. There is no need for an unmap helper given that kunmap_local accept any address in the mapped page. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/20210727055646.118787-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* bvec: fix the include guards for bvec.hChristoph Hellwig2021-08-021-3/+3
| | | | | | | | | | | | Fix the include guards to match the file naming. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/20210727055646.118787-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: optimise for_each_bvec() advancePavel Begunkov2020-12-021-5/+15
| | | | | | | | | | | | | | | | | | | | Because of how for_each_bvec() works it never advances across multiple entries at a time, so bvec_iter_advance() is an overkill. Add specialised bvec_iter_advance_single() that is faster. It also handles zero-len bvecs, so can kill bvec_iter_skip_zero_bvec(). text data bss dec hex filename before: 23977 805 0 24782 60ce lib/iov_iter.o before, bvec_iter_advance() w/o WARN_ONCE() 22886 600 0 23486 5bbe ./lib/iov_iter.o after: 21862 600 0 22462 57be lib/iov_iter.o Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* kernel.h: split out min()/max() et al. helpersAndy Shevchenko2020-10-161-1/+5
| | | | | | | | | | | | | | | | | | | | kernel.h is being used as a dump for all kinds of stuff for a long time. Here is the attempt to start cleaning it up by splitting out min()/max() et al. helpers. At the same time convert users in header and lib folder to use new header. Though for time being include new header back to kernel.h to avoid twisted indirected includes for other existing users. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Joe Perches <joe@perches.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lkml.kernel.org/r/20200910164152.GA1891694@smile.fi.intel.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* block: allow for_each_bvec to support zero len bvecMing Lei2020-09-021-1/+8
| | | | | | | | | | | | | | | | | | | | Block layer usually doesn't support or allow zero-length bvec. Since commit 1bdc76aea115 ("iov_iter: use bvec iterator to implement iterate_bvec()"), iterate_bvec() switches to bvec iterator. However, Al mentioned that 'Zero-length segments are not disallowed' in iov_iter. Fixes for_each_bvec() so that it can move on after seeing one zero length bvec. Fixes: 1bdc76aea115 ("iov_iter: use bvec iterator to implement iterate_bvec()") Reported-by: syzbot <syzbot+61acc40a49a3e46e25ea@syzkaller.appspotmail.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Tested-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Matthew Wilcox <willy@infradead.org> Cc: <stable@vger.kernel.org> Link: https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg2262077.html Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: Document the bio_vec propertiesBart Van Assche2020-05-191-2/+11
| | | | | | | | | | | Since it is nontrivial that nth_page() does not have to be used for a bio_vec, document this. Signed-off-by: Bart Van Assche <bvanassche@acm.org> Reviewed-by: Christoph Hellwig <hch@lst.de> CC: Christoph Hellwig <hch@infradead.org> Cc: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: remove unused mp_bvec_last_segmentJens Axboe2020-01-041-22/+0
| | | | | | | | After commit 85a8ce62c2ea ("block: add bio_truncate to fix guard_bio_eod") this function is unused, remove it. Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: optimise bvec_iter_advance()Pavel Begunkov2019-12-031-12/+10
| | | | | | | | | | | | | | | | bvec_iter_advance() is quite popular, but compilers fail to do proper alias analysis and optimise it good enough. The assembly is checked for gcc 9.2, x86-64. - remove @iter->bi_size from min(...), as it's always less than @bytes. Modify at the beginning and forget about it. - the compiler isn't able to collapse memory dependencies and remove writes in the loop. Help it by explicitely using local vars. Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: fix mismerge in bvec_advanceChristoph Hellwig2019-05-071-7/+1
| | | | | | | | | | | When Jens merged my commit to only allow contiguous page structs in a bio_vec with Ming's 5.1 fix to ensue the bvec length didn't overflow we failed to keep the removal of the expensive nth_page calls. This commits adds them back as intended. Fixes: 5c61ee2cd586 ("Merge tag 'v5.1-rc6' into for-5.2/block") Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: switch all files cleared marked as GPLv2 to SPDX tagsChristoph Hellwig2019-04-301-14/+1
| | | | | | | | | All these files have some form of the usual GPLv2 boilerplate. Switch them to use SPDX tags instead. Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* Merge tag 'v5.1-rc6' into for-5.2/blockJens Axboe2019-04-221-6/+18
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull in v5.1-rc6 to resolve two conflicts. One is in BFQ, in just a comment, and is trivial. The other one is a conflict due to a later fix in the bio multi-page work, and needs a bit more care. * tag 'v5.1-rc6': (770 commits) Linux 5.1-rc6 block: make sure that bvec length can't be overflow block: kill all_q_node in request_queue x86/cpu/intel: Lower the "ENERGY_PERF_BIAS: Set to normal" message's log priority coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping mm/kmemleak.c: fix unused-function warning init: initialize jump labels before command line option parsing kernel/watchdog_hld.c: hard lockup message should end with a newline kcov: improve CONFIG_ARCH_HAS_KCOV help text mm: fix inactive list balancing between NUMA nodes and cgroups mm/hotplug: treat CMA pages as unmovable proc: fixup proc-pid-vm test proc: fix map_files test on F29 mm/vmstat.c: fix /proc/vmstat format for CONFIG_DEBUG_TLBFLUSH=y CONFIG_SMP=n mm/memory_hotplug: do not unlock after failing to take the device_hotplug_lock mm: swapoff: shmem_unuse() stop eviction without igrab() mm: swapoff: take notice of completion sooner mm: swapoff: remove too limiting SWAP_UNUSE_MAX_TRIES mm: swapoff: shmem_find_swap_entries() filter out other types slab: store tagged freelist for off-slab slabmgmt ... Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * block: make sure that bvec length can't be overflowMing Lei2019-04-191-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | bvec->bv_offset may be bigger than PAGE_SIZE sometimes, such as, when one bio is splitted in the middle of one bvec via bio_split(), and bi_iter.bi_bvec_done is used to build offset of the 1st bvec of remained bio. And the remained bio's bvec may be re-submitted to fs layer via ITER_IBVEC, such as loop and nvme-loop. So we have to make sure that every bvec's offset is less than PAGE_SIZE from bio_for_each_segment_all() because some drivers(loop, nvme-loop) passes the splitted bvec to fs layer via ITER_BVEC. This patch fixes this issue reported by Zhang Yi When running nvme/011. Cc: Christoph Hellwig <hch@lst.de> Cc: Yi Zhang <yi.zhang@redhat.com> Reported-by: Yi Zhang <yi.zhang@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Fixes: 6dc4f100c175 ("block: allow bio_for_each_segment_all() to iterate over multi-page bvec") Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * block: don't use for-inside-for in bio_for_each_segment_allMing Lei2019-04-081-4/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 6dc4f100c175 ("block: allow bio_for_each_segment_all() to iterate over multi-page bvec") changes bio_for_each_segment_all() to use for-inside-for. This way breaks all bio_for_each_segment_all() call with error out branch via 'break', since now 'break' can only break from the inner loop. Fixes this issue by implementing bio_for_each_segment_all() via single 'for' loop, and now the logic is very similar with normal bvec iterator. Cc: Qu Wenruo <quwenruo.btrfs@gmx.com> Cc: linux-btrfs@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Cc: Omar Sandoval <osandov@fb.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reported-and-Tested-by: Qu Wenruo <quwenruo.btrfs@gmx.com> Fixes: 6dc4f100c175 ("block: allow bio_for_each_segment_all() to iterate over multi-page bvec") Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | block: only allow contiguous page structs in a bio_vecChristoph Hellwig2019-04-121-9/+4
| | | | | | | | | | | | | | | | | | | | | | We currently have to call nth_page when iterating over pages inside a bio_vec. Jens complained a while ago that this is fairly expensive. To mitigate this we can check that that the actual page structures are contiguous when adding them to the bio, and just do check pointer arithmetics later on. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | block: change how we get page references in bio_iov_iter_get_pagesChristoph Hellwig2019-04-121-5/+0
|/ | | | | | | | | | | Instead of needing a special macro to iterate over all pages in a bvec just do a second passs over the whole bio. This also matches what we do on the release side. The release side helper is moved up to where we need the get helper to clearly express the symmetry. Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: optimize bvec iteration in bvec_iter_advanceChristoph Hellwig2019-02-281-3/+4
| | | | | | | | | | | | | | There is no need to only iterate in chunks of PAGE_SIZE or less in bvec_iter_advance, given that the callers pass in the chunk length that they are operating on - either that already is less than PAGE_SIZE because they do classic page-based iteration, or it is larger because the caller operates on multi-page bvecs. This should help shaving off a few cycles of the I/O hot path. Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: introduce mp_bvec_for_each_page() for iterating over pageMing Lei2019-02-281-0/+5
| | | | | | | | | mp_bvec_for_each_segment() is a bit big for the iteration, so introduce a light-weight helper for iterating over pages, then 32bytes stack space can be saved. Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: introduce bvec_nth_page()Ming Lei2019-02-271-3/+8
| | | | | | | | | Single-page bvec can often be seen in small BS workloads, so introduce bvec_nth_page() for avoiding to call nth_page() unnecessarily, which looks not cheap. Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: allow bio_for_each_segment_all() to iterate over multi-page bvecMing Lei2019-02-151-0/+30
| | | | | | | | | | | | | | This patch introduces one extra iterator variable to bio_for_each_segment_all(), then we can allow bio_for_each_segment_all() to iterate over multi-page bvec. Given it is just one mechannical & simple change on all bio_for_each_segment_all() users, this patch does tree-wide change in one single patch, so that we can avoid to use a temporary helper for this conversion. Reviewed-by: Omar Sandoval <osandov@fb.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: introduce mp_bvec_last_segment()Ming Lei2019-02-151-0/+22
| | | | | | | | | BTRFS and guard_bio_eod() need to get the last singlepage segment from one multipage bvec, so introduce this helper to make them happy. Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: introduce multi-page bvec helpersMing Lei2019-02-151-3/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces helpers of 'mp_bvec_iter_*' for multi-page bvec support. The introduced helpers treate one bvec as real multi-page segment, which may include more than one pages. The existed helpers of bvec_iter_* are interfaces for supporting current bvec iterator which is thought as single-page by drivers, fs, dm and etc. These introduced helpers will build single-page bvec in flight, so this way won't break current bio/bvec users, which needn't any change. Follows some multi-page bvec background: - bvecs stored in bio->bi_io_vec is always multi-page style - bvec(struct bio_vec) represents one physically contiguous I/O buffer, now the buffer may include more than one page after multi-page bvec is supported, and all these pages represented by one bvec is physically contiguous. Before multi-page bvec support, at most one page is included in one bvec, we call it single-page bvec. - .bv_page of the bvec points to the 1st page in the multi-page bvec - .bv_offset of the bvec is the offset of the buffer in the bvec The effect on the current drivers/filesystem/dm/bcache/...: - almost everyone supposes that one bvec only includes one single page, so we keep the sp interface not changed, for example, bio_for_each_segment() still returns single-page bvec - bio_for_each_segment_all() will return single-page bvec too - during iterating, iterator variable(struct bvec_iter) is always updated in multi-page bvec style, and bvec_iter_advance() is kept not changed - returned(copied) single-page bvec is built in flight by bvec helpers from the stored multi-page bvec Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: remove bvec_iter_rewind()Ming Lei2019-02-151-24/+0
| | | | | | | | | | | Commit 7759eb23fd980 ("block: remove bio_rewind_iter()") removes bio_rewind_iter(), then no one uses bvec_iter_rewind() any more, so remove it. Reviewed-by: Omar Sandoval <osandov@fb.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: remove bio_rewind_iter()Ming Lei2018-09-061-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | It is pointed that bio_rewind_iter() is one very bad API[1]: 1) bio size may not be restored after rewinding 2) it causes some bogus change, such as 5151842b9d8732 (block: reset bi_iter.bi_done after splitting bio) 3) rewinding really makes things complicated wrt. bio splitting 4) unnecessary updating of .bi_done in fast path [1] https://marc.info/?t=153549924200005&r=1&w=2 So this patch takes Kent's suggestion to restore one bio into its original state via saving bio iterator(struct bvec_iter) in bio_integrity_prep(), given now bio_rewind_iter() is only used by bio integrity code. Cc: Dmitry Monakhov <dmonakhov@openvz.org> Cc: Hannes Reinecke <hare@suse.com> Suggested-by: Kent Overstreet <kent.overstreet@gmail.com> Acked-by: Kent Overstreet <kent.overstreet@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: bounce: don't access bio->bi_io_vec in copy_to_high_bio_irqMing Lei2018-01-061-0/+9
| | | | | | | | | | | Firstly this patch introduces BVEC_ITER_ALL_INIT for iterating one bio from start to end. As we need to support multipage bvecs, don't access bio->bi_io_vec in copy_to_high_bio_irq(), and just use the standard iterator for that. Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* bio: add bvec_iter rewind APIDmitry Monakhov2017-07-031-0/+27
| | | | | | | | | | | | | | | | | | | Some ->bi_end_io handlers (for example: pi_verify or decrypt handlers) need to know original data vector, but after bio traverse io-stack it may be advanced, splited and relocated many times so it is hard to guess original iterator. Let's add 'bi_done' conter which accounts number of bytes iterator was advanced during it's evolution. Later end_io handler may easily restore original iterator by rewinding iterator to iter->bi_done. Note: this change makes sizeof (struct bvec_iter) multiple to 8 Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> [hch: switched to true/false return] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* block: guard bvec iteration logicDmitry Monakhov2017-07-031-5/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently if some one try to advance bvec beyond it's size we simply dump WARN_ONCE and continue to iterate beyond bvec array boundaries. This simply means that we endup dereferencing/corrupting random memory region. Sane reaction would be to propagate error back to calling context But bvec_iter_advance's calling context is not always good for error handling. For safity reason let truncate iterator size to zero which will break external iteration loop which prevent us from unpredictable memory range corruption. And even it caller ignores an error, it will corrupt it's own bvecs, not others. This patch does: - Return error back to caller with hope that it will react on this - Truncate iterator size Code was added long time ago here 4550dd6c, luckily no one hit it in real life :) Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Reviewed-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> [hch: switch to true/false returns instead of errno values] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* bvec: avoid variable shadowing warningJohannes Berg2016-08-111-1/+2
| | | | | | | | | | Due to the (indirect) nesting of min(..., min(...)), sparse will show a variable shadowing warning whenever bvec.h is included. Avoid that by assigning the inner min() to a temporary variable first. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* block: mark 1st parameter of bvec_iter_advance as constMing Lei2016-06-091-1/+2
| | | | | | | | | | | | | | bvec_iter_advance() only writes the parameter of iterator, so the base address of bvec can be marked as const safely. Without the change, we can see compiling warning in the following patch for implementing iterate_bvec(): lib/iov_iter.c with bvec iterator. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@canonical.com> Tested-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* block: move two bvec structure into bvec.hMing Lei2016-06-091-1/+22
| | | | | | | | | | | | | | | | This patch moves 'struct bio_vec' and 'struct bvec_iter' into 'include/linux/bvec.h', then always include this header into 'include/linux/blk_types.h'. With this change, both 'struct bvec_iter' and bvec iterator helpers don't depend on CONFIG_BLOCK any more, then we can use bvec iterator to implement iterate_bvec(): lib/iov_iter.c. Reviewed-by: Christoph Hellwig <hch@lst.de> Suggested-by: Christoph Hellwig <hch@infradead.org> Signed-off-by: Ming Lei <ming.lei@canonical.com> Tested-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
* block: move bvec iterator into include/linux/bvec.hMing Lei2016-06-091-0/+74
bvec iterator helpers should be used to implement by iterate_bvec():lib/iov_iter.c too, and move them into one header, so that we can keep bvec iterator header out of CONFIG_BLOCK. Then we can remove the reinventing of wheel in iterate_bvec(). Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@canonical.com> Tested-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-12 12:43:06 +0000