summaryrefslogtreecommitdiff
path: root/mm/hugetlb.c
AgeCommit message (Collapse)Author
2023-06-19mm/folio: avoid special handling for order value 0 in folio_set_orderTarun Sahu
folio_set_order(folio, 0) is used in kernel at two places __destroy_compound_gigantic_folio and __prep_compound_gigantic_folio. Currently, It is called to clear out the folio->_folio_nr_pages and folio->_folio_order. For __destroy_compound_gigantic_folio: In past, folio_set_order(folio, 0) was needed because page->mapping used to overlap with _folio_nr_pages and _folio_order. So if these fields were left uncleared during freeing gigantic hugepages, they were causing "BUG: bad page state" due to non-zero page->mapping. Now, After Commit a01f43901cfb ("hugetlb: be sure to free demoted CMA pages to CMA") page->mapping has explicitly been cleared out for tail pages. Also, _folio_order and _folio_nr_pages no longer overlaps with page->mapping. So, folio_set_order(folio, 0) can be removed from freeing gigantic folio path (__destroy_compound_gigantic_folio). Another place, folio_set_order(folio, 0) is called inside __prep_compound_gigantic_folio during error path. Here, folio_set_order(folio, 0) can also be removed if we move folio_set_order(folio, order) after for loop. The patch also moves _folio_set_head call in __prep_compound_gigantic_folio() such that we avoid clearing them in the error path. Also, as Mike pointed out: "It would actually be better to move the calls _folio_set_head and folio_set_order in __prep_compound_gigantic_folio() as suggested here. Why? In the current code, the ref count on the 'head page' is still 1 (or more) while those calls are made. So, someone could take a speculative ref on the page BEFORE the tail pages are set up." This way, folio_set_order(folio, 0) is no more needed. And it will also helps removing the confusion of folio order being set to 0 (as _folio_order field is part of first tail page). Testing: I have run LTP tests, which all passes. and also I have written the test in LTP which tests the bug caused by compound_nr and page->mapping overlapping. https://github.com/linux-test-project/ltp/blob/master/testcases/kernel/mem/hugetlb/hugemmap/hugemmap32.c Running on older kernel ( < 5.10-rc7) with the above bug this fails while on newer kernel and, also with this patch it passes. Link: https://lkml.kernel.org/r/20230609162907.111756-1-tsahu@linux.ibm.com Signed-off-by: Tarun Sahu <tsahu@linux.ibm.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-19mm/hugetlb: use a folio in hugetlb_fault()ZhangPeng
We can replace seven implicit calls to compound_head() with one by using folio. [akpm@linux-foundation.org: update comment, per Sidhartha] Link: https://lkml.kernel.org/r/20230606062013.2947002-4-zhangpeng362@huawei.com Signed-off-by: ZhangPeng <zhangpeng362@huawei.com> Reviewed-by Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-19mm/hugetlb: use a folio in hugetlb_wp()ZhangPeng
We can replace nine implict calls to compound_head() with one by using old_folio. The page we get back is always a head page, so we just convert old_page to old_folio. Link: https://lkml.kernel.org/r/20230606062013.2947002-3-zhangpeng362@huawei.com Signed-off-by: ZhangPeng <zhangpeng362@huawei.com> Suggested-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-19mm/hugetlb: use a folio in copy_hugetlb_page_range()ZhangPeng
Patch series "Convert several functions in hugetlb.c to use a folio", v2. This patch series converts three functions in hugetlb.c to use a folio, which can remove several implicit calls to compound_head(). This patch (of 3): We can replace five implict calls to compound_head() with one by using pte_folio. The page we get back is always a head page, so we just convert ptepage to pte_folio. Link: https://lkml.kernel.org/r/20230606062013.2947002-1-zhangpeng362@huawei.com Link: https://lkml.kernel.org/r/20230606062013.2947002-2-zhangpeng362@huawei.com Signed-off-by: ZhangPeng <zhangpeng362@huawei.com> Suggested-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Reviewed-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09mm/gup: remove vmas array from internal GUP functionsLorenzo Stoakes
Now we have eliminated all callers to GUP APIs which use the vmas parameter, eliminate it altogether. This eliminates a class of bugs where vmas might have been kept around longer than the mmap_lock and thus we need not be concerned about locks being dropped during this operation leaving behind dangling pointers. This simplifies the GUP API and makes it considerably clearer as to its purpose - follow flags are applied and if pinning, an array of pages is returned. Link: https://lkml.kernel.org/r/6811b4b2b4b3baf3dd07f422bb18853bb2cd09fb.1684350871.git.lstoakes@gmail.com Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christian König <christian.koenig@amd.com> Cc: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Janosch Frank <frankja@linux.ibm.com> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Sakari Ailus <sakari.ailus@linux.intel.com> Cc: Sean Christopherson <seanjc@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-27Merge tag 'mm-stable-2023-04-27-15-30' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Nick Piggin's "shoot lazy tlbs" series, to improve the peformance of switching from a user process to a kernel thread. - More folio conversions from Kefeng Wang, Zhang Peng and Pankaj Raghav. - zsmalloc performance improvements from Sergey Senozhatsky. - Yue Zhao has found and fixed some data race issues around the alteration of memcg userspace tunables. - VFS rationalizations from Christoph Hellwig: - removal of most of the callers of write_one_page() - make __filemap_get_folio()'s return value more useful - Luis Chamberlain has changed tmpfs so it no longer requires swap backing. Use `mount -o noswap'. - Qi Zheng has made the slab shrinkers operate locklessly, providing some scalability benefits. - Keith Busch has improved dmapool's performance, making part of its operations O(1) rather than O(n). - Peter Xu adds the UFFD_FEATURE_WP_UNPOPULATED feature to userfaultd, permitting userspace to wr-protect anon memory unpopulated ptes. - Kirill Shutemov has changed MAX_ORDER's meaning to be inclusive rather than exclusive, and has fixed a bunch of errors which were caused by its unintuitive meaning. - Axel Rasmussen give userfaultfd the UFFDIO_CONTINUE_MODE_WP feature, which causes minor faults to install a write-protected pte. - Vlastimil Babka has done some maintenance work on vma_merge(): cleanups to the kernel code and improvements to our userspace test harness. - Cleanups to do_fault_around() by Lorenzo Stoakes. - Mike Rapoport has moved a lot of initialization code out of various mm/ files and into mm/mm_init.c. - Lorenzo Stoakes removd vmf_insert_mixed_prot(), which was added for DRM, but DRM doesn't use it any more. - Lorenzo has also coverted read_kcore() and vread() to use iterators and has thereby removed the use of bounce buffers in some cases. - Lorenzo has also contributed further cleanups of vma_merge(). - Chaitanya Prakash provides some fixes to the mmap selftesting code. - Matthew Wilcox changes xfs and afs so they no longer take sleeping locks in ->map_page(), a step towards RCUification of pagefaults. - Suren Baghdasaryan has improved mmap_lock scalability by switching to per-VMA locking. - Frederic Weisbecker has reworked the percpu cache draining so that it no longer causes latency glitches on cpu isolated workloads. - Mike Rapoport cleans up and corrects the ARCH_FORCE_MAX_ORDER Kconfig logic. - Liu Shixin has changed zswap's initialization so we no longer waste a chunk of memory if zswap is not being used. - Yosry Ahmed has improved the performance of memcg statistics flushing. - David Stevens has fixed several issues involving khugepaged, userfaultfd and shmem. - Christoph Hellwig has provided some cleanup work to zram's IO-related code paths. - David Hildenbrand has fixed up some issues in the selftest code's testing of our pte state changing. - Pankaj Raghav has made page_endio() unneeded and has removed it. - Peter Xu contributed some rationalizations of the userfaultfd selftests. - Yosry Ahmed has fixed an issue around memcg's page recalim accounting. - Chaitanya Prakash has fixed some arm-related issues in the selftests/mm code. - Longlong Xia has improved the way in which KSM handles hwpoisoned pages. - Peter Xu fixes a few issues with uffd-wp at fork() time. - Stefan Roesch has changed KSM so that it may now be used on a per-process and per-cgroup basis. * tag 'mm-stable-2023-04-27-15-30' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits) mm,unmap: avoid flushing TLB in batch if PTE is inaccessible shmem: restrict noswap option to initial user namespace mm/khugepaged: fix conflicting mods to collapse_file() sparse: remove unnecessary 0 values from rc mm: move 'mmap_min_addr' logic from callers into vm_unmapped_area() hugetlb: pte_alloc_huge() to replace huge pte_alloc_map() maple_tree: fix allocation in mas_sparse_area() mm: do not increment pgfault stats when page fault handler retries zsmalloc: allow only one active pool compaction context selftests/mm: add new selftests for KSM mm: add new KSM process and sysfs knobs mm: add new api to enable ksm per process mm: shrinkers: fix debugfs file permissions mm: don't check VMA write permissions if the PTE/PMD indicates write permissions migrate_pages_batch: fix statistics for longterm pin retry userfaultfd: use helper function range_in_vma() lib/show_mem.c: use for_each_populated_zone() simplify code mm: correct arg in reclaim_pages()/reclaim_clean_pages_from_list() fs/buffer: convert create_page_buffers to folio_create_buffers fs/buffer: add folio_create_empty_buffers helper ...
2023-04-27Merge tag 'sysctl-6.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux Pull sysctl updates from Luis Chamberlain: "This only does a few sysctl moves from the kernel/sysctl.c file, the rest of the work has been put towards deprecating two API calls which incur recursion and prevent us from simplifying the registration process / saving memory per move. Most of the changes have been soaking on linux-next since v6.3-rc3. I've slowed down the kernel/sysctl.c moves due to Matthew Wilcox's feedback that we should see if we could *save* memory with these moves instead of incurring more memory. We currently incur more memory since when we move a syctl from kernel/sysclt.c out to its own file we end up having to add a new empty sysctl used to register it. To achieve saving memory we want to allow syctls to be passed without requiring the end element being empty, and just have our registration process rely on ARRAY_SIZE(). Without this, supporting both styles of sysctls would make the sysctl registration pretty brittle, hard to read and maintain as can be seen from Meng Tang's efforts to do just this [0]. Fortunately, in order to use ARRAY_SIZE() for all sysctl registrations also implies doing the work to deprecate two API calls which use recursion in order to support sysctl declarations with subdirectories. And so during this development cycle quite a bit of effort went into this deprecation effort. I've annotated the following two APIs are deprecated and in few kernel releases we should be good to remove them: - register_sysctl_table() - register_sysctl_paths() During this merge window we should be able to deprecate and unexport register_sysctl_paths(), we can probably do that towards the end of this merge window. Deprecating register_sysctl_table() will take a bit more time but this pull request goes with a few example of how to do this. As it turns out each of the conversions to move away from either of these two API calls *also* saves memory. And so long term, all these changes *will* prove to have saved a bit of memory on boot. The way I see it then is if remove a user of one deprecated call, it gives us enough savings to move one kernel/sysctl.c out from the generic arrays as we end up with about the same amount of bytes. Since deprecating register_sysctl_table() and register_sysctl_paths() does not require maintainer coordination except the final unexport you'll see quite a bit of these changes from other pull requests, I've just kept the stragglers after rc3" Link: https://lkml.kernel.org/r/ZAD+cpbrqlc5vmry@bombadil.infradead.org [0] * tag 'sysctl-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (29 commits) fs: fix sysctls.c built mm: compaction: remove incorrect #ifdef checks mm: compaction: move compaction sysctl to its own file mm: memory-failure: Move memory failure sysctls to its own file arm: simplify two-level sysctl registration for ctl_isa_vars ia64: simplify one-level sysctl registration for kdump_ctl_table utsname: simplify one-level sysctl registration for uts_kern_table ntfs: simplfy one-level sysctl registration for ntfs_sysctls coda: simplify one-level sysctl registration for coda_table fs/cachefiles: simplify one-level sysctl registration for cachefiles_sysctls xfs: simplify two-level sysctl registration for xfs_table nfs: simplify two-level sysctl registration for nfs_cb_sysctls nfs: simplify two-level sysctl registration for nfs4_cb_sysctls lockd: simplify two-level sysctl registration for nlm_sysctls proc_sysctl: enhance documentation xen: simplify sysctl registration for balloon md: simplify sysctl registration hv: simplify sysctl registration scsi: simplify sysctl registration with register_sysctl() csky: simplify alignment sysctl registration ...
2023-04-21mm/hugetlb: fix uffd-wp bit lost when unsharing happensPeter Xu
When we try to unshare a pinned page for a private hugetlb, uffd-wp bit can get lost during unsharing. When above condition met, one can lose uffd-wp bit on the privately mapped hugetlb page. It allows the page to be writable even if it should still be wr-protected. I assume it can mean data loss. This should be very rare, only if an unsharing happened on a private hugetlb page with uffd-wp protected (e.g. in a child which shares the same page with parent with UFFD_FEATURE_EVENT_FORK enabled). When I wrote the reproducer (provided in the last patch) I needed to use the newest gup_test cmd introduced by David to trigger it because I don't even know another way to do a proper RO longerm pin. Besides that, it needs a bunch of other conditions all met: (1) hugetlb being mapped privately, (2) userfaultfd registered with WP and EVENT_FORK, (3) the user app fork()s, then, (4) RO longterm pin onto a wr-protected anonymous page. If it's not impossible to hit in production I'd say extremely rare. Link: https://lkml.kernel.org/r/20230417195317.898696-3-peterx@redhat.com Fixes: 166f3ecc0daf ("mm/hugetlb: hook page faults for uffd write protection") Signed-off-by: Peter Xu <peterx@redhat.com> Reported-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Mika Penttilä <mpenttil@redhat.com> Cc: Nadav Amit <nadav.amit@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-21mm/hugetlb: fix uffd-wp during fork()Peter Xu
Patch series "mm/hugetlb: More fixes around uffd-wp vs fork() / RO pins", v2. This patch (of 6): There're a bunch of things that were wrong: - Reading uffd-wp bit from a swap entry should use pte_swp_uffd_wp() rather than huge_pte_uffd_wp(). - When copying over a pte, we should drop uffd-wp bit when !EVENT_FORK (aka, when !userfaultfd_wp(dst_vma)). - When doing early CoW for private hugetlb (e.g. when the parent page was pinned), uffd-wp bit should be properly carried over if necessary. No bug reported probably because most people do not even care about these corner cases, but they are still bugs and can be exposed by the recent unit tests introduced, so fix all of them in one shot. Link: https://lkml.kernel.org/r/20230417195317.898696-1-peterx@redhat.com Link: https://lkml.kernel.org/r/20230417195317.898696-2-peterx@redhat.com Fixes: bc70fbf269fd ("mm/hugetlb: handle uffd-wp during fork()") Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Mika Penttilä <mpenttil@redhat.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-18mm: hwpoison: support recovery from HugePage copy-on-write faultsLiu Shixin
copy-on-write of hugetlb user pages with uncorrectable errors will result in a kernel crash. This is because the copy is performed in kernel mode and in general we can not handle accessing memory with such errors while in kernel mode. Commit a873dfe1032a ("mm, hwpoison: try to recover from copy-on write faults") introduced the routine copy_user_highpage_mc() to gracefully handle copying of user pages with uncorrectable errors. However, the separate hugetlb copy-on-write code paths were not modified as part of commit a873dfe1032a. Modify hugetlb copy-on-write code paths to use copy_mc_user_highpage() so that they can also gracefully handle uncorrectable errors in user pages. This involves changing the hugetlb specific routine copy_user_large_folio() from type void to int so that it can return an error. Modify the hugetlb userfaultfd code in the same way so that it can return -EHWPOISON if it encounters an uncorrectable error. Link: https://lkml.kernel.org/r/20230413131349.2524210-1-liushixin2@huawei.com Signed-off-by: Liu Shixin <liushixin2@huawei.com> Acked-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Tony Luck <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-18mm: convert copy_user_huge_page() to copy_user_large_folio()ZhangPeng
Replace copy_user_huge_page() with copy_user_large_folio(). copy_user_large_folio() does the same as copy_user_huge_page(), but takes in folios instead of pages. Remove pages_per_huge_page from copy_user_large_folio(), because we can get that from folio_nr_pages(dst). Convert copy_user_gigantic_page() to take in folios. Link: https://lkml.kernel.org/r/20230410133932.32288-6-zhangpeng362@huawei.com Signed-off-by: ZhangPeng <zhangpeng362@huawei.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-18userfaultfd: convert mfill_atomic_hugetlb() to use a folioZhangPeng
Convert hugetlb_mfill_atomic_pte() to take in a folio pointer instead of a page pointer. Convert mfill_atomic_hugetlb() to use a folio. Link: https://lkml.kernel.org/r/20230410133932.32288-5-zhangpeng362@huawei.com Signed-off-by: ZhangPeng <zhangpeng362@huawei.com> Reviewed-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-18userfaultfd: convert copy_huge_page_from_user() to copy_folio_from_user()ZhangPeng
Replace copy_huge_page_from_user() with copy_folio_from_user(). copy_folio_from_user() does the same as copy_huge_page_from_user(), but takes in a folio instead of a page. Convert page_kaddr to kaddr in copy_folio_from_user() to do indenting cleanup. Link: https://lkml.kernel.org/r/20230410133932.32288-4-zhangpeng362@huawei.com Signed-off-by: ZhangPeng <zhangpeng362@huawei.com> Reviewed-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nanyong Sun <sunnanyong@huawei.com> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-18hugetlb: remove PageHeadHuge()Matthew Wilcox (Oracle)
Sidhartha Kumar removed the last caller of PageHeadHuge(), so we can now remove it and make folio_test_hugetlb() the real implementation. Add kernel-doc for folio_test_hugetlb(). Link: https://lkml.kernel.org/r/20230327151050.1787744-1-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-16sync mm-stable with mm-hotfixes-stable to pick up depended-upon upstream changesAndrew Morton
2023-04-05mm: userfaultfd: combine 'mode' and 'wp_copy' argumentsAxel Rasmussen
Many userfaultfd ioctl functions take both a 'mode' and a 'wp_copy' argument. In future commits we plan to plumb the flags through to more places, so we'd be proliferating the very long argument list even further. Let's take the time to simplify the argument list. Combine the two arguments into one - and generalize, so when we add more flags in the future, it doesn't imply more function arguments. Since the modes (copy, zeropage, continue) are mutually exclusive, store them as an integer value (0, 1, 2) in the low bits. Place combine-able flag bits in the high bits. This is quite similar to an earlier patch proposed by Nadav Amit ("userfaultfd: introduce uffd_flags" [1]). The main difference is that patch only handled flags, whereas this patch *also* combines the "mode" argument into the same type to shorten the argument list. [1]: https://lore.kernel.org/all/20220619233449.181323-2-namit@vmware.com/ Link: https://lkml.kernel.org/r/20230314221250.682452-4-axelrasmussen@google.com Signed-off-by: Axel Rasmussen <axelrasmussen@google.com> Acked-by: James Houghton <jthoughton@google.com> Acked-by: Peter Xu <peterx@redhat.com> Acked-by: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Hugh Dickins <hughd@google.com> Cc: Jan Kara <jack@suse.cz> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-05mm: userfaultfd: don't pass around both mm and vmaAxel Rasmussen
Quite a few userfaultfd functions took both mm and vma pointers as arguments. Since the mm is trivially accessible via vma->vm_mm, there's no reason to pass both; it just needlessly extends the already long argument list. Get rid of the mm pointer, where possible, to shorten the argument list. Link: https://lkml.kernel.org/r/20230314221250.682452-3-axelrasmussen@google.com Signed-off-by: Axel Rasmussen <axelrasmussen@google.com> Acked-by: Peter Xu <peterx@redhat.com> Acked-by: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Hugh Dickins <hughd@google.com> Cc: James Houghton <jthoughton@google.com> Cc: Jan Kara <jack@suse.cz> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nadav Amit <namit@vmware.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-05mm: userfaultfd: rename functions for clarity + consistencyAxel Rasmussen
Patch series "mm: userfaultfd: refactor and add UFFDIO_CONTINUE_MODE_WP", v5. - Commits 1-3 refactor userfaultfd ioctl code without behavior changes, with the main goal of improving consistency and reducing the number of function args. - Commit 4 adds UFFDIO_CONTINUE_MODE_WP. This patch (of 4): The basic problem is, over time we've added new userfaultfd ioctls, and we've refactored the code so functions which used to handle only one case are now re-used to deal with several cases. While this happened, we didn't bother to rename the functions. Similarly, as we added new functions, we cargo-culted pieces of the now-inconsistent naming scheme, so those functions too ended up with names that don't make a lot of sense. A key point here is, "copy" in most userfaultfd code refers specifically to UFFDIO_COPY, where we allocate a new page and copy its contents from userspace. There are many functions with "copy" in the name that don't actually do this (at least in some cases). So, rename things into a consistent scheme. The high level idea is that the call stack for userfaultfd ioctls becomes: userfaultfd_ioctl -> userfaultfd_(particular ioctl) -> mfill_atomic_(particular kind of fill operation) -> mfill_atomic /* loops over pages in range */ -> mfill_atomic_pte /* deals with single pages */ -> mfill_atomic_pte_(particular kind of fill operation) -> mfill_atomic_install_pte There are of course some special cases (shmem, hugetlb), but this is the general structure which all function names now adhere to. Link: https://lkml.kernel.org/r/20230314221250.682452-1-axelrasmussen@google.com Link: https://lkml.kernel.org/r/20230314221250.682452-2-axelrasmussen@google.com Signed-off-by: Axel Rasmussen <axelrasmussen@google.com> Acked-by: Peter Xu <peterx@redhat.com> Acked-by: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Hugh Dickins <hughd@google.com> Cc: James Houghton <jthoughton@google.com> Cc: Jan Kara <jack@suse.cz> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nadav Amit <namit@vmware.com> Cc: Shuah Khan <shuah@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-05mm, treewide: redefine MAX_ORDER sanelyKirill A. Shutemov
MAX_ORDER currently defined as number of orders page allocator supports: user can ask buddy allocator for page order between 0 and MAX_ORDER-1. This definition is counter-intuitive and lead to number of bugs all over the kernel. Change the definition of MAX_ORDER to be inclusive: the range of orders user can ask from buddy allocator is 0..MAX_ORDER now. [kirill@shutemov.name: fix min() warning] Link: https://lkml.kernel.org/r/20230315153800.32wib3n5rickolvh@box [akpm@linux-foundation.org: fix another min_t warning] [kirill@shutemov.name: fixups per Zi Yan] Link: https://lkml.kernel.org/r/20230316232144.b7ic4cif4kjiabws@box.shutemov.name [akpm@linux-foundation.org: fix underlining in docs] Link: https://lore.kernel.org/oe-kbuild-all/202303191025.VRCTk6mP-lkp@intel.com/ Link: https://lkml.kernel.org/r/20230315113133.11326-11-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc] Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-05mm: return an ERR_PTR from __filemap_get_folioChristoph Hellwig
Instead of returning NULL for all errors, distinguish between: - no entry found and not asked to allocated (-ENOENT) - failed to allocate memory (-ENOMEM) - would block (-EAGAIN) so that callers don't have to guess the error based on the passed in flags. Also pass through the error through the direct callers: filemap_get_folio, filemap_lock_folio filemap_grab_folio and filemap_get_incore_folio. [hch@lst.de: fix null-pointer deref] Link: https://lkml.kernel.org/r/20230310070023.GA13563@lst.de Link: https://lkml.kernel.org/r/20230310043137.GA1624890@u2004 Link: https://lkml.kernel.org/r/20230307143410.28031-8-hch@lst.de Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> [nilfs2] Cc: Andreas Gruenbacher <agruenba@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-05mm/hugetlb: fix uffd wr-protection for CoW optimization pathPeter Xu
This patch fixes an issue that a hugetlb uffd-wr-protected mapping can be writable even with uffd-wp bit set. It only happens with hugetlb private mappings, when someone firstly wr-protects a missing pte (which will install a pte marker), then a write to the same page without any prior access to the page. Userfaultfd-wp trap for hugetlb was implemented in hugetlb_fault() before reaching hugetlb_wp() to avoid taking more locks that userfault won't need. However there's one CoW optimization path that can trigger hugetlb_wp() inside hugetlb_no_page(), which will bypass the trap. This patch skips hugetlb_wp() for CoW and retries the fault if uffd-wp bit is detected. The new path will only trigger in the CoW optimization path because generic hugetlb_fault() (e.g. when a present pte was wr-protected) will resolve the uffd-wp bit already. Also make sure anonymous UNSHARE won't be affected and can still be resolved, IOW only skip CoW not CoR. This patch will be needed for v5.19+ hence copy stable. [peterx@redhat.com: v2] Link: https://lkml.kernel.org/r/ZBzOqwF2wrHgBVZb@x1n [peterx@redhat.com: v3] Link: https://lkml.kernel.org/r/20230324142620.2344140-1-peterx@redhat.com Link: https://lkml.kernel.org/r/20230321191840.1897940-1-peterx@redhat.com Fixes: 166f3ecc0daf ("mm/hugetlb: hook page faults for uffd write protection") Signed-off-by: Peter Xu <peterx@redhat.com> Reported-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Tested-by: Muhammad Usama Anjum <usama.anjum@collabora.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-03-20mm: hugetlb: move hugeltb sysctls to its own fileKefeng Wang
This moves all hugetlb sysctls to its own file, also kill an useless hugetlb_treat_movable_handler() defination. Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-02-20mm: hugetlb: change to return bool for isolate_hugetlb()Baolin Wang
Now the isolate_hugetlb() only returns 0 or -EBUSY, and most users did not care about the negative value, thus we can convert the isolate_hugetlb() to return a boolean value to make code more clear when checking the hugetlb isolation state. Moreover converts 2 users which will consider the negative value returned by isolate_hugetlb(). No functional changes intended. [akpm@linux-foundation.org: shorten locked section, per SeongJae Park] Link: https://lkml.kernel.org/r/12a287c5bebc13df304387087bbecc6421510849.1676424378.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: convert hugetlb_wp() to take in a folioSidhartha Kumar
Change the pagecache_page argument of hugetlb_wp to pagecache_folio. Replaces a call to find_lock_page() with filemap_lock_folio(). Link: https://lkml.kernel.org/r/20230125170537.96973-8-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reported-by: gerald.schaefer@linux.ibm.com Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: convert hugetlb_add_to_page_cache to take in a folioSidhartha Kumar
Every caller of hugetlb_add_to_page_cache() is now passing in &folio->page, change the function to take in a folio directly and clean up the call sites. Link: https://lkml.kernel.org/r/20230125170537.96973-7-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: convert restore_reserve_on_error to take in a folioSidhartha Kumar
Every caller of restore_reserve_on_error() is now passing in &folio->page, change the function to take in a folio directly and clean up the call sites. Link: https://lkml.kernel.org/r/20230125170537.96973-6-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: convert hugetlb fault paths to use alloc_hugetlb_folio()Sidhartha Kumar
Change alloc_huge_page() to alloc_hugetlb_folio() by changing all callers to handle the now folio return type of the function. In this conversion, alloc_huge_page_vma() is also changed to alloc_hugetlb_folio_vma() and hugepage_add_new_anon_rmap() is changed to take in a folio directly. Many additions of '&folio->page' are cleaned up in subsequent patches. hugetlbfs_fallocate() is also refactored to use the RCU + page_cache_next_miss() API. Link: https://lkml.kernel.org/r/20230125170537.96973-5-sidhartha.kumar@oracle.com Suggested-by: Mike Kravetz <mike.kravetz@oracle.com> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: convert putback_active_hugepage to take in a folioSidhartha Kumar
Convert putback_active_hugepage() to folio_putback_active_hugetlb(), this removes one user of the Huge Page macros which take in a page. The callers in migrate.c are also cleaned up by being able to directly use the src and dst folio variables. Link: https://lkml.kernel.org/r/20230125170537.96973-4-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: convert hugetlbfs_pagecache_present() to foliosSidhartha Kumar
Refactor hugetlbfs_pagecache_present() to avoid getting and dropping a refcount on a page. Use RCU and page_cache_next_miss() instead. Link: https://lkml.kernel.org/r/20230125170537.96973-3-sidhartha.kumar@oracle.com Suggested-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: kernel test robot <lkp@intel.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: convert hugetlb_install_page to foliosSidhartha Kumar
Patch series "convert hugetlb fault functions to folios", v2. This series converts the hugetlb page faulting functions to operate on folios. These include hugetlb_no_page(), hugetlb_wp(), copy_hugetlb_page_range(), and hugetlb_mcopy_atomic_pte(). This patch (of 8): Change hugetlb_install_page() to hugetlb_install_folio(). This reduces one user of the Huge Page flag macros which take in a page. Link: https://lkml.kernel.org/r/20230125170537.96973-1-sidhartha.kumar@oracle.com Link: https://lkml.kernel.org/r/20230125170537.96973-2-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: convert demote_free_huge_page to foliosSidhartha Kumar
Change demote_free_huge_page to demote_free_hugetlb_folio() and change demote_pool_huge_page() pass in a folio. Link: https://lkml.kernel.org/r/20230113223057.173292-9-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: convert restore_reserve_on_error() to foliosSidhartha Kumar
Use the hugetlb folio flag macros inside restore_reserve_on_error() and update the comments to reflect the use of folios. Link: https://lkml.kernel.org/r/20230113223057.173292-8-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: convert alloc_migrate_huge_page to foliosSidhartha Kumar
Change alloc_huge_page_nodemask() to alloc_hugetlb_folio_nodemask() and alloc_migrate_huge_page() to alloc_migrate_hugetlb_folio(). Both functions now return a folio rather than a page. Link: https://lkml.kernel.org/r/20230113223057.173292-7-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: increase use of folios in alloc_huge_page()Sidhartha Kumar
Change hugetlb_cgroup_commit_charge{,_rsvd}(), dequeue_huge_page_vma() and alloc_buddy_huge_page_with_mpol() to use folios so alloc_huge_page() is cleaned by operating on folios until its return. Link: https://lkml.kernel.org/r/20230113223057.173292-6-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: convert alloc_surplus_huge_page() to foliosSidhartha Kumar
Change alloc_surplus_huge_page() to alloc_surplus_hugetlb_folio() and update its callers. Link: https://lkml.kernel.org/r/20230113223057.173292-5-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: convert dequeue_hugetlb_page functions to foliosSidhartha Kumar
dequeue_huge_page_node_exact() is changed to dequeue_hugetlb_folio_node_ exact() and dequeue_huge_page_nodemask() is changed to dequeue_hugetlb_ folio_nodemask(). Update their callers to pass in a folio. Link: https://lkml.kernel.org/r/20230113223057.173292-4-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: convert __update_and_free_page() to foliosSidhartha Kumar
Change __update_and_free_page() to __update_and_free_hugetlb_folio() by changing its callers to pass in a folio. Link: https://lkml.kernel.org/r/20230113223057.173292-3-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: convert isolate_hugetlb to foliosSidhartha Kumar
Patch series "continue hugetlb folio conversion", v3. This series continues the conversion of core hugetlb functions to use folios. This series converts many helper funtions in the hugetlb fault path. This is in preparation for another series to convert the hugetlb fault code paths to operate on folios. This patch (of 8): Convert isolate_hugetlb() to take in a folio and convert its callers to pass a folio. Use page_folio() to convert the callers to use a folio is safe as isolate_hugetlb() operates on a head page. Link: https://lkml.kernel.org/r/20230113223057.173292-1-sidhartha.kumar@oracle.com Link: https://lkml.kernel.org/r/20230113223057.173292-2-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-09mm: replace VM_LOCKED_CLEAR_MASK with VM_LOCKED_MASKSuren Baghdasaryan
To simplify the usage of VM_LOCKED_CLEAR_MASK in vm_flags_clear(), replace it with VM_LOCKED_MASK bitmask and convert all users. Link: https://lkml.kernel.org/r/20230126193752.297968-4-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Mike Rapoport (IBM) <rppt@kernel.org> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjun Roy <arjunroy@google.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Greg Thelen <gthelen@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Joel Fernandes <joelaf@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kent Overstreet <kent.overstreet@linux.dev> Cc: Laurent Dufour <ldufour@linux.ibm.com> Cc: Liam R. Howlett <Liam.Howlett@Oracle.com> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Minchan Kim <minchan@google.com> Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Peter Oskolkov <posk@google.com> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Punit Agrawal <punit.agrawal@bytedance.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Sebastian Reichel <sebastian.reichel@collabora.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Cc: Song Liu <songliubraving@fb.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02mm/hugetlb: convert get_hwpoison_huge_page() to foliosSidhartha Kumar
Straightforward conversion of get_hwpoison_huge_page() to get_hwpoison_hugetlb_folio(). Reduces two references to a head page in memory-failure.c [arnd@arndb.de: fix get_hwpoison_hugetlb_folio() stub] Link: https://lkml.kernel.org/r/20230119111920.635260-1-arnd@kernel.org Link: https://lkml.kernel.org/r/20230118174039.14247-1-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02mm/memory-failure: convert hugetlb_clear_page_hwpoison to foliosSidhartha Kumar
Change hugetlb_clear_page_hwpoison() to folio_clear_hugetlb_hwpoison() by changing the function to take in a folio. This converts one use of ClearPageHWPoison and HPageRawHwpUnreliable to their folio equivalents. Link: https://lkml.kernel.org/r/20230112204608.80136-4-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02hugetlb: remove uses of compound_dtor and compound_nrMatthew Wilcox (Oracle)
Convert the entire file to use the folio equivalents. Link: https://lkml.kernel.org/r/20230111142915.1001531-22-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02hugetlb: remove uses of folio_mapcount_ptrMatthew Wilcox (Oracle)
Use the entire_mapcount field directly. Link: https://lkml.kernel.org/r/20230111142915.1001531-14-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02mm: convert head_subpages_mapcount() into folio_nr_pages_mapped()Matthew Wilcox (Oracle)
Calling this 'mapcount' is confusing since mapcount is usually the number of times something is mapped; instead this is the number of mapped pages. It's also better to enforce that this is a folio rather than a head page. Move folio_nr_pages_mapped() into mm/internal.h since this is not something we want device drivers or filesystems poking at. Get rid of folio_subpages_mapcount_ptr() and use folio->_nr_pages_mapped directly. Link: https://lkml.kernel.org/r/20230111142915.1001531-3-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02mm: remove folio_pincount_ptr() and head_compound_pincount()Matthew Wilcox (Oracle)
We can use folio->_pincount directly, since all users are guarded by tests of compound/large. Link: https://lkml.kernel.org/r/20230111142915.1001531-2-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-02mm/mmu_notifier: remove unused mmu_notifier_range_update_to_read_only exportAlistair Popple
mmu_notifier_range_update_to_read_only() was originally introduced in commit c6d23413f81b ("mm/mmu_notifier: mmu_notifier_range_update_to_read_only() helper") as an optimisation for device drivers that know a range has only been mapped read-only. However there are no users of this feature so remove it. As it is the only user of the struct mmu_notifier_range.vma field remove that also. Link: https://lkml.kernel.org/r/20230110025722.600912-1-apopple@nvidia.com Signed-off-by: Alistair Popple <apopple@nvidia.com> Acked-by: Mike Rapoport (IBM) <rppt@kernel.org> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18mm/uffd: detect pgtable allocation failuresPeter Xu
Before this patch, when there's any pgtable allocation issues happened during change_protection(), the error will be ignored from the syscall. For shmem, there will be an error dumped into the host dmesg. Two issues with that: (1) Doing a trace dump when allocation fails is not anything close to grace. (2) The user should be notified with any kind of such error, so the user can trap it and decide what to do next, either by retrying, or stop the process properly, or anything else. For userfault users, this will change the API of UFFDIO_WRITEPROTECT when pgtable allocation failure happened. It should not normally break anyone, though. If it breaks, then in good ways. One man-page update will be on the way to introduce the new -ENOMEM for UFFDIO_WRITEPROTECT. Not marking stable so we keep the old behavior on the 5.19-till-now kernels. [akpm@linux-foundation.org: coding-style cleanups] Link: https://lkml.kernel.org/r/20230104225207.1066932-4-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reported-by: James Houghton <jthoughton@google.com> Acked-by: James Houghton <jthoughton@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: David Hildenbrand <david@redhat.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Nadav Amit <nadav.amit@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18mm/mprotect: use long for page accountings and retvalPeter Xu
Switch to use type "long" for page accountings and retval across the whole procedure of change_protection(). The change should have shrinked the possible maximum page number to be half comparing to previous (ULONG_MAX / 2), but it shouldn't overflow on any system either because the maximum possible pages touched by change protection should be ULONG_MAX / PAGE_SIZE. Two reasons to switch from "unsigned long" to "long": 1. It suites better on count_vm_numa_events(), whose 2nd parameter takes a long type. 2. It paves way for returning negative (error) values in the future. Currently the only caller that consumes this retval is change_prot_numa(), where the unsigned long was converted to an int. Since at it, touching up the numa code to also take a long, so it'll avoid any possible overflow too during the int-size convertion. Link: https://lkml.kernel.org/r/20230104225207.1066932-3-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Acked-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: James Houghton <jthoughton@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: David Hildenbrand <david@redhat.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Nadav Amit <nadav.amit@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18hugetlb: initialize variable to avoid compiler warningMike Kravetz
With the gcc 'maybe-uninitialized' warning enabled, gcc will produce: mm/hugetlb.c:6896:20: warning: `chg' may be used uninitialized This is a false positive, but may be difficult for the compiler to determine. maybe-uninitialized is disabled by default, but this gets flagged as a 0-DAY build regression. Initialize the variable to silence the warning. Link: https://lkml.kernel.org/r/20221216224507.106789-1-mike.kravetz@oracle.com Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18mm/hugetlb: introduce hugetlb_walk()Peter Xu
huge_pte_offset() is the main walker function for hugetlb pgtables. The name is not really representing what it does, though. Instead of renaming it, introduce a wrapper function called hugetlb_walk() which will use huge_pte_offset() inside. Assert on the locks when walking the pgtable. Note, the vma lock assertion will be a no-op for private mappings. Document the last special case in the page_vma_mapped_walk() path where we don't need any more lock to call hugetlb_walk(). Taking vma lock there is not needed because either: (1) potential callers of hugetlb pvmw holds i_mmap_rwsem already (from one rmap_walk()), or (2) the caller will not walk a hugetlb vma at all so the hugetlb code path not reachable (e.g. in ksm or uprobe paths). It's slightly implicit for future page_vma_mapped_walk() callers on that lock requirement. But anyway, when one day this rule breaks, one will get a straightforward warning in hugetlb_walk() with lockdep, then there'll be a way out. [akpm@linux-foundation.org: coding-style cleanups] Link: https://lkml.kernel.org/r/20221216155229.2043750-1-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: James Houghton <jthoughton@google.com> Cc: Jann Horn <jannh@google.com> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>