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* mm/shmem: restore SHMEM_HUGE_DENY precedence over MADV_COLLAPSEZach O'Keefe2023-01-111-4/+2
| | | | | | | | | | | | | | | | | | | SHMEM_HUGE_DENY is for emergency use by the admin, to disable allocation of shmem huge pages if, for example, a dangerous bug is found in their usage: see "deny" in Documentation/mm/transhuge.rst. An app using madvise(,,MADV_COLLAPSE) should not be allowed to override it: restore its precedence over shmem_huge_force. Restore SHMEM_HUGE_DENY precedence over MADV_COLLAPSE. Link: https://lkml.kernel.org/r/20221224082035.3197140-2-zokeefe@google.com Fixes: 7c6c6cc4d3a2 ("mm/shmem: add flag to enforce shmem THP in hugepage_vma_check()") Signed-off-by: Zach O'Keefe <zokeefe@google.com> Suggested-by: Hugh Dickins <hughd@google.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Yang Shi <shy828301@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Merge tag 'mm-stable-2022-12-13' of ↵Linus Torvalds2022-12-131-20/+34
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - More userfaultfs work from Peter Xu - Several convert-to-folios series from Sidhartha Kumar and Huang Ying - Some filemap cleanups from Vishal Moola - David Hildenbrand added the ability to selftest anon memory COW handling - Some cpuset simplifications from Liu Shixin - Addition of vmalloc tracing support by Uladzislau Rezki - Some pagecache folioifications and simplifications from Matthew Wilcox - A pagemap cleanup from Kefeng Wang: we have VM_ACCESS_FLAGS, so use it - Miguel Ojeda contributed some cleanups for our use of the __no_sanitize_thread__ gcc keyword. This series should have been in the non-MM tree, my bad - Naoya Horiguchi improved the interaction between memory poisoning and memory section removal for huge pages - DAMON cleanups and tuneups from SeongJae Park - Tony Luck fixed the handling of COW faults against poisoned pages - Peter Xu utilized the PTE marker code for handling swapin errors - Hugh Dickins reworked compound page mapcount handling, simplifying it and making it more efficient - Removal of the autonuma savedwrite infrastructure from Nadav Amit and David Hildenbrand - zram support for multiple compression streams from Sergey Senozhatsky - David Hildenbrand reworked the GUP code's R/O long-term pinning so that drivers no longer need to use the FOLL_FORCE workaround which didn't work very well anyway - Mel Gorman altered the page allocator so that local IRQs can remnain enabled during per-cpu page allocations - Vishal Moola removed the try_to_release_page() wrapper - Stefan Roesch added some per-BDI sysfs tunables which are used to prevent network block devices from dirtying excessive amounts of pagecache - David Hildenbrand did some cleanup and repair work on KSM COW breaking - Nhat Pham and Johannes Weiner have implemented writeback in zswap's zsmalloc backend - Brian Foster has fixed a longstanding corner-case oddity in file[map]_write_and_wait_range() - sparse-vmemmap changes for MIPS, LoongArch and NIOS2 from Feiyang Chen - Shiyang Ruan has done some work on fsdax, to make its reflink mode work better under xfstests. Better, but still not perfect - Christoph Hellwig has removed the .writepage() method from several filesystems. They only need .writepages() - Yosry Ahmed wrote a series which fixes the memcg reclaim target beancounting - David Hildenbrand has fixed some of our MM selftests for 32-bit machines - Many singleton patches, as usual * tag 'mm-stable-2022-12-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (313 commits) mm/hugetlb: set head flag before setting compound_order in __prep_compound_gigantic_folio mm: mmu_gather: allow more than one batch of delayed rmaps mm: fix typo in struct pglist_data code comment kmsan: fix memcpy tests mm: add cond_resched() in swapin_walk_pmd_entry() mm: do not show fs mm pc for VM_LOCKONFAULT pages selftests/vm: ksm_functional_tests: fixes for 32bit selftests/vm: cow: fix compile warning on 32bit selftests/vm: madv_populate: fix missing MADV_POPULATE_(READ|WRITE) definitions mm/gup_test: fix PIN_LONGTERM_TEST_READ with highmem mm,thp,rmap: fix races between updates of subpages_mapcount mm: memcg: fix swapcached stat accounting mm: add nodes= arg to memory.reclaim mm: disable top-tier fallback to reclaim on proactive reclaim selftests: cgroup: make sure reclaim target memcg is unprotected selftests: cgroup: refactor proactive reclaim code to reclaim_until() mm: memcg: fix stale protection of reclaim target memcg mm/mmap: properly unaccount memory on mas_preallocate() failure omfs: remove ->writepage jfs: remove ->writepage ...
| * Merge branch 'mm-hotfixes-stable' into mm-stableAndrew Morton2022-12-091-0/+11
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| * | mm: anonymous shared memory namingPasha Tatashin2022-11-301-4/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit 9a10064f5625 ("mm: add a field to store names for private anonymous memory"), name for private anonymous memory, but not shared anonymous, can be set. However, naming shared anonymous memory just as useful for tracking purposes. Extend the functionality to be able to set names for shared anon. There are two ways to create anonymous shared memory, using memfd or directly via mmap(): 1. fd = memfd_create(...) mem = mmap(..., MAP_SHARED, fd, ...) 2. mem = mmap(..., MAP_SHARED | MAP_ANONYMOUS, -1, ...) In both cases the anonymous shared memory is created the same way by mapping an unlinked file on tmpfs. The memfd way allows to give a name for anonymous shared memory, but not useful when parts of shared memory require to have distinct names. Example use case: The VMM maps VM memory as anonymous shared memory (not private because VMM is sandboxed and drivers are running in their own processes). However, the VM tells back to the VMM how parts of the memory are actually used by the guest, how each of the segments should be backed (i.e. 4K pages, 2M pages), and some other information about the segments. The naming allows us to monitor the effective memory footprint for each of these segments from the host without looking inside the guest. Sample output: /* Create shared anonymous segmenet */ anon_shmem = mmap(NULL, SIZE, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0); /* Name the segment: "MY-NAME" */ rv = prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, anon_shmem, SIZE, "MY-NAME"); cat /proc/<pid>/maps (and smaps): 7fc8e2b4c000-7fc8f2b4c000 rw-s 00000000 00:01 1024 [anon_shmem:MY-NAME] If the segment is not named, the output is: 7fc8e2b4c000-7fc8f2b4c000 rw-s 00000000 00:01 1024 /dev/zero (deleted) Link: https://lkml.kernel.org/r/20221115020602.804224-1-pasha.tatashin@soleen.com Signed-off-by: Pasha Tatashin <pasha.tatashin@soleen.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Bagas Sanjaya <bagasdotme@gmail.com> Cc: Colin Cross <ccross@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: "Kirill A . Shutemov" <kirill@shutemov.name> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Peter Xu <peterx@redhat.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Vincent Whitchurch <vincent.whitchurch@axis.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: xu xin <cgel.zte@gmail.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| * | mm: use pte markers for swap errorsPeter Xu2022-11-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PTE markers are ideal mechanism for things like SWP_SWAPIN_ERROR. Using a whole swap entry type for this purpose can be an overkill, especially if we already have PTE markers. Define a new bit for swapin error and replace it with pte markers. Then we can safely drop SWP_SWAPIN_ERROR and give one device slot back to swap. We used to have SWP_SWAPIN_ERROR taking the page pfn as part of the swap entry, but it's never used. Neither do I see how it can be useful because normally the swapin failure should not be caused by a bad page but bad swap device. Drop it alongside. Link: https://lkml.kernel.org/r/20221030214151.402274-3-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Huang Ying <ying.huang@intel.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| * | tmpfs: ensure O_LARGEFILE with generic_file_open()Thomas Weißschuh2022-11-081-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Without this check open() will open large files on tmpfs although O_LARGEFILE was not specified. This is inconsistent with other filesystems. Also it will later result in EOVERFLOW on stat() or EFBIG on write(). Link: https://lore.kernel.org/lkml/76bedae6-22ea-4abc-8c06-b424ceb39217@t-8ch.de/ Link: https://lkml.kernel.org/r/20220928104535.61186-1-linux@weissschuh.net Signed-off-by: Thomas Weißschuh <thomas.weissschuh@amadeus.com> Acked-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| * | mm/shmem: remove unneeded assignments in shmem_get_folio_gfp()Lukas Bulwahn2022-11-081-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After the rework of shmem_get_folio_gfp() to use a folio, the local variable hindex is only needed to be set once before passing it to shmem_add_to_page_cache(). Remove the unneeded initialization and assignments of the variable hindex before the actual effective assignment and first use. No functional change. No change in object code. Link: https://lkml.kernel.org/r/20221007085027.6309-1-lukas.bulwahn@gmail.com Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Cc: Hugh Dickins <hughd@google.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| * | filemap: find_get_entries() now updates start offsetVishal Moola (Oracle)2022-11-081-7/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Initially, find_get_entries() was being passed in the start offset as a value. That left the calculation of the offset to the callers. This led to complexity in the callers trying to keep track of the index. Now find_get_entries() takes in a pointer to the start offset and updates the value to be directly after the last entry found. If no entry is found, the offset is not changed. This gets rid of multiple hacky calculations that kept track of the start offset. Link: https://lkml.kernel.org/r/20221017161800.2003-3-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Hugh Dickins <hughd@google.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| * | filemap: find_lock_entries() now updates start offsetVishal Moola (Oracle)2022-11-081-6/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "Rework find_get_entries() and find_lock_entries()", v3. Originally the callers of find_get_entries() and find_lock_entries() were keeping track of the start index themselves as they traverse the search range. This resulted in hacky code such as in shmem_undo_range(): index = folio->index + folio_nr_pages(folio) - 1; where the - 1 is only present to stay in the right spot after incrementing index later. This sort of calculation was also being done on every folio despite not even using index later within that function. These patches change find_get_entries() and find_lock_entries() to calculate the new index instead of leaving it to the callers so we can avoid all these complications. This patch (of 2): Initially, find_lock_entries() was being passed in the start offset as a value. That left the calculation of the offset to the callers. This led to complexity in the callers trying to keep track of the index. Now find_lock_entries() takes in a pointer to the start offset and updates the value to be directly after the last entry found. If no entry is found, the offset is not changed. This gets rid of multiple hacky calculations that kept track of the start offset. Link: https://lkml.kernel.org/r/20221017161800.2003-1-vishal.moola@gmail.com Link: https://lkml.kernel.org/r/20221017161800.2003-2-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Hugh Dickins <hughd@google.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | | Merge tag 'fs.xattr.simple.rework.rbtree.rwlock.v6.2' of ↵Linus Torvalds2022-12-131-1/+1
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping Pull simple-xattr updates from Christian Brauner: "This ports the simple xattr infrastucture to rely on a simple rbtree protected by a read-write lock instead of a linked list protected by a spinlock. A while ago we received reports about scaling issues for filesystems using the simple xattr infrastructure that also support setting a larger number of xattrs. Specifically, cgroups and tmpfs. Both cgroupfs and tmpfs can be mounted by unprivileged users in unprivileged containers and root in an unprivileged container can set an unrestricted number of security.* xattrs and privileged users can also set unlimited trusted.* xattrs. A few more words on further that below. Other xattrs such as user.* are restricted for kernfs-based instances to a fairly limited number. As there are apparently users that have a fairly large number of xattrs we should scale a bit better. Using a simple linked list protected by a spinlock used for set, get, and list operations doesn't scale well if users use a lot of xattrs even if it's not a crazy number. Let's switch to a simple rbtree protected by a rwlock. It scales way better and gets rid of the perf issues some people reported. We originally had fancier solutions even using an rcu+seqlock protected rbtree but we had concerns about being to clever and also that deletion from an rbtree with rcu+seqlock isn't entirely safe. The rbtree plus rwlock is perfectly fine. By far the most common operation is getting an xattr. While setting an xattr is not and should be comparatively rare. And listxattr() often only happens when copying xattrs between files or together with the contents to a new file. Holding a lock across listxattr() is unproblematic because it doesn't list the values of xattrs. It can only be used to list the names of all xattrs set on a file. And the number of xattr names that can be listed with listxattr() is limited to XATTR_LIST_MAX aka 65536 bytes. If a larger buffer is passed then vfs_listxattr() caps it to XATTR_LIST_MAX and if more xattr names are found it will return -E2BIG. In short, the maximum amount of memory that can be retrieved via listxattr() is limited and thus listxattr() bounded. Of course, the API is broken as documented on xattr(7) already. While I have no idea how the xattr api ended up in this state we should probably try to come up with something here at some point. An iterator pattern similar to readdir() as an alternative to listxattr() or something else. Right now it is extremly strange that users can set millions of xattrs but then can't use listxattr() to know which xattrs are actually set. And it's really trivial to do: for i in {1..1000000}; do setfattr -n security.$i -v $i ./file1; done And around 5000 xattrs it's impossible to use listxattr() to figure out which xattrs are actually set. So I have suggested that we try to limit the number of xattrs for simple xattrs at least. But that's a future patch and I don't consider it very urgent. A bonus of this port to rbtree+rwlock is that we shrink the memory consumption for users of the simple xattr infrastructure. This also adds kernel documentation to all the functions" * tag 'fs.xattr.simple.rework.rbtree.rwlock.v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping: xattr: use rbtree for simple_xattrs
| * | | xattr: use rbtree for simple_xattrsChristian Brauner2022-11-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A while ago Vasily reported that it is possible to set a large number of xattrs on inodes of filesystems that make use of the simple xattr infrastructure. This includes all kernfs-based filesystems that support xattrs (e.g., cgroupfs and tmpfs). Both cgroupfs and tmpfs can be mounted by unprivileged users in unprivileged containers and root in an unprivileged container can set an unrestricted number of security.* xattrs and privileged users can also set unlimited trusted.* xattrs. As there are apparently users that have a fairly large number of xattrs we should scale a bit better. Other xattrs such as user.* are restricted for kernfs-based instances to a fairly limited number. Using a simple linked list protected by a spinlock used for set, get, and list operations doesn't scale well if users use a lot of xattrs even if it's not a crazy number. There's no need to bring in the big guns like rhashtables or rw semaphores for this. An rbtree with a rwlock, or limited rcu semanics and seqlock is enough. It scales within the constraints we are working in. By far the most common operation is getting an xattr. Setting xattrs should be a moderately rare operation. And listxattr() often only happens when copying xattrs between files or together with the contents to a new file. Holding a lock across listxattr() is unproblematic because it doesn't list the values of xattrs. It can only be used to list the names of all xattrs set on a file. And the number of xattr names that can be listed with listxattr() is limited to XATTR_LIST_MAX aka 65536 bytes. If a larger buffer is passed then vfs_listxattr() caps it to XATTR_LIST_MAX and if more xattr names are found it will return -E2BIG. In short, the maximum amount of memory that can be retrieved via listxattr() is limited. Of course, the API is broken as documented on xattr(7) already. In the future we might want to address this but for now this is the world we live in and have lived for a long time. But it does indeed mean that once an application goes over XATTR_LIST_MAX limit of xattrs set on an inode it isn't possible to copy the file and include its xattrs in the copy unless the caller knows all xattrs or limits the copy of the xattrs to important ones it knows by name (At least for tmpfs, and kernfs-based filesystems. Other filesystems might provide ways of achieving this.). Bonus of this port to rbtree+rwlock is that we shrink the memory consumption for users of the simple xattr infrastructure. Also add proper kernel documentation to all the functions. A big thanks to Paul for his comments. Cc: Vasily Averin <vvs@openvz.org> Cc: "Paul E. McKenney" <paulmck@kernel.org> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
* | | | Merge tag 'fs.acl.rework.v6.2' of ↵Linus Torvalds2022-12-121-1/+1
|\ \ \ \ | |_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping Pull VFS acl updates from Christian Brauner: "This contains the work that builds a dedicated vfs posix acl api. The origins of this work trace back to v5.19 but it took quite a while to understand the various filesystem specific implementations in sufficient detail and also come up with an acceptable solution. As we discussed and seen multiple times the current state of how posix acls are handled isn't nice and comes with a lot of problems: The current way of handling posix acls via the generic xattr api is error prone, hard to maintain, and type unsafe for the vfs until we call into the filesystem's dedicated get and set inode operations. It is already the case that posix acls are special-cased to death all the way through the vfs. There are an uncounted number of hacks that operate on the uapi posix acl struct instead of the dedicated vfs struct posix_acl. And the vfs must be involved in order to interpret and fixup posix acls before storing them to the backing store, caching them, reporting them to userspace, or for permission checking. Currently a range of hacks and duct tape exist to make this work. As with most things this is really no ones fault it's just something that happened over time. But the code is hard to understand and difficult to maintain and one is constantly at risk of introducing bugs and regressions when having to touch it. Instead of continuing to hack posix acls through the xattr handlers this series builds a dedicated posix acl api solely around the get and set inode operations. Going forward, the vfs_get_acl(), vfs_remove_acl(), and vfs_set_acl() helpers must be used in order to interact with posix acls. They operate directly on the vfs internal struct posix_acl instead of abusing the uapi posix acl struct as we currently do. In the end this removes all of the hackiness, makes the codepaths easier to maintain, and gets us type safety. This series passes the LTP and xfstests suites without any regressions. For xfstests the following combinations were tested: - xfs - ext4 - btrfs - overlayfs - overlayfs on top of idmapped mounts - orangefs - (limited) cifs There's more simplifications for posix acls that we can make in the future if the basic api has made it. A few implementation details: - The series makes sure to retain exactly the same security and integrity module permission checks. Especially for the integrity modules this api is a win because right now they convert the uapi posix acl struct passed to them via a void pointer into the vfs struct posix_acl format to perform permission checking on the mode. There's a new dedicated security hook for setting posix acls which passes the vfs struct posix_acl not a void pointer. Basing checking on the posix acl stored in the uapi format is really unreliable. The vfs currently hacks around directly in the uapi struct storing values that frankly the security and integrity modules can't correctly interpret as evidenced by bugs we reported and fixed in this area. It's not necessarily even their fault it's just that the format we provide to them is sub optimal. - Some filesystems like 9p and cifs need access to the dentry in order to get and set posix acls which is why they either only partially or not even at all implement get and set inode operations. For example, cifs allows setxattr() and getxattr() operations but doesn't allow permission checking based on posix acls because it can't implement a get acl inode operation. Thus, this patch series updates the set acl inode operation to take a dentry instead of an inode argument. However, for the get acl inode operation we can't do this as the old get acl method is called in e.g., generic_permission() and inode_permission(). These helpers in turn are called in various filesystem's permission inode operation. So passing a dentry argument to the old get acl inode operation would amount to passing a dentry to the permission inode operation which we shouldn't and probably can't do. So instead of extending the existing inode operation Christoph suggested to add a new one. He also requested to ensure that the get and set acl inode operation taking a dentry are consistently named. So for this version the old get acl operation is renamed to ->get_inode_acl() and a new ->get_acl() inode operation taking a dentry is added. With this we can give both 9p and cifs get and set acl inode operations and in turn remove their complex custom posix xattr handlers. In the future I hope to get rid of the inode method duplication but it isn't like we have never had this situation. Readdir is just one example. And frankly, the overall gain in type safety and the more pleasant api wise are simply too big of a benefit to not accept this duplication for a while. - We've done a full audit of every codepaths using variant of the current generic xattr api to get and set posix acls and surprisingly it isn't that many places. There's of course always a chance that we might have missed some and if so I'm sure we'll find them soon enough. The crucial codepaths to be converted are obviously stacking filesystems such as ecryptfs and overlayfs. For a list of all callers currently using generic xattr api helpers see [2] including comments whether they support posix acls or not. - The old vfs generic posix acl infrastructure doesn't obey the create and replace semantics promised on the setxattr(2) manpage. This patch series doesn't address this. It really is something we should revisit later though. The patches are roughly organized as follows: (1) Change existing set acl inode operation to take a dentry argument (Intended to be a non-functional change) (2) Rename existing get acl method (Intended to be a non-functional change) (3) Implement get and set acl inode operations for filesystems that couldn't implement one before because of the missing dentry. That's mostly 9p and cifs (Intended to be a non-functional change) (4) Build posix acl api, i.e., add vfs_get_acl(), vfs_remove_acl(), and vfs_set_acl() including security and integrity hooks (Intended to be a non-functional change) (5) Implement get and set acl inode operations for stacking filesystems (Intended to be a non-functional change) (6) Switch posix acl handling in stacking filesystems to new posix acl api now that all filesystems it can stack upon support it. (7) Switch vfs to new posix acl api (semantical change) (8) Remove all now unused helpers (9) Additional regression fixes reported after we merged this into linux-next Thanks to Seth for a lot of good discussion around this and encouragement and input from Christoph" * tag 'fs.acl.rework.v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping: (36 commits) posix_acl: Fix the type of sentinel in get_acl orangefs: fix mode handling ovl: call posix_acl_release() after error checking evm: remove dead code in evm_inode_set_acl() cifs: check whether acl is valid early acl: make vfs_posix_acl_to_xattr() static acl: remove a slew of now unused helpers 9p: use stub posix acl handlers cifs: use stub posix acl handlers ovl: use stub posix acl handlers ecryptfs: use stub posix acl handlers evm: remove evm_xattr_acl_change() xattr: use posix acl api ovl: use posix acl api ovl: implement set acl method ovl: implement get acl method ecryptfs: implement set acl method ecryptfs: implement get acl method ksmbd: use vfs_remove_acl() acl: add vfs_remove_acl() ...
| * | | fs: pass dentry to set acl methodChristian Brauner2022-10-191-1/+1
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current way of setting and getting posix acls through the generic xattr interface is error prone and type unsafe. The vfs needs to interpret and fixup posix acls before storing or reporting it to userspace. Various hacks exist to make this work. The code is hard to understand and difficult to maintain in it's current form. Instead of making this work by hacking posix acls through xattr handlers we are building a dedicated posix acl api around the get and set inode operations. This removes a lot of hackiness and makes the codepaths easier to maintain. A lot of background can be found in [1]. Since some filesystem rely on the dentry being available to them when setting posix acls (e.g., 9p and cifs) they cannot rely on set acl inode operation. But since ->set_acl() is required in order to use the generic posix acl xattr handlers filesystems that do not implement this inode operation cannot use the handler and need to implement their own dedicated posix acl handlers. Update the ->set_acl() inode method to take a dentry argument. This allows all filesystems to rely on ->set_acl(). As far as I can tell all codepaths can be switched to rely on the dentry instead of just the inode. Note that the original motivation for passing the dentry separate from the inode instead of just the dentry in the xattr handlers was because of security modules that call security_d_instantiate(). This hook is called during d_instantiate_new(), d_add(), __d_instantiate_anon(), and d_splice_alias() to initialize the inode's security context and possibly to set security.* xattrs. Since this only affects security.* xattrs this is completely irrelevant for posix acls. Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1] Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
* | | tmpfs: fix data loss from failed fallocateHugh Dickins2022-12-091-0/+11
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix tmpfs data loss when the fallocate system call is interrupted by a signal, or fails for some other reason. The partial folio handling in shmem_undo_range() forgot to consider this unfalloc case, and was liable to erase or truncate out data which had already been committed earlier. It turns out that none of the partial folio handling there is appropriate for the unfalloc case, which just wants to proceed to removal of whole folios: which find_get_entries() provides, even when partially covered. Original patch by Rui Wang. Link: https://lore.kernel.org/linux-mm/33b85d82.7764.1842e9ab207.Coremail.chenguoqic@163.com/ Link: https://lkml.kernel.org/r/a5dac112-cf4b-7af-a33-f386e347fd38@google.com Fixes: b9a8a4195c7d ("truncate,shmem: Handle truncates that split large folios") Signed-off-by: Hugh Dickins <hughd@google.com> Reported-by: Guoqi Chen <chenguoqic@163.com> Link: https://lore.kernel.org/all/20221101032248.819360-1-kernel@hev.cc/ Cc: Rui Wang <kernel@hev.cc> Cc: Huacai Chen <chenhuacai@loongson.cn> Cc: Matthew Wilcox <willy@infradead.org> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: <stable@vger.kernel.org> [5.17+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | mm/shmem: ensure proper fallback if page faultsIra Weiny2022-10-281-0/+17
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kernel test robot flagged a recursive lock as a result of a conversion from kmap_atomic() to kmap_local_folio()[Link] The cause was due to the code depending on the kmap_atomic() side effect of disabling page faults. In that case the code expects the fault to fail and take the fallback case. git archaeology implied that the recursion may not be an actual bug.[1] However, depending on the implementation of the mmap_lock and the condition of the call there may still be a deadlock.[2] So this is not purely a lockdep issue. Considering a single threaded call stack there are 3 options. 1) Different mm's are in play (no issue) 2) Readlock implementation is recursive and same mm is in play (no issue) 3) Readlock implementation is _not_ recursive (issue) The mmap_lock is recursive so with a single thread there is no issue. However, Matthew pointed out a deadlock scenario when you consider additional process' and threads thusly. "The readlock implementation is only recursive if nobody else has taken a write lock. If you have a multithreaded process, one of the other threads can call mmap() and that will prevent recursion (due to fairness). Even if it's a different process that you're trying to acquire the mmap read lock on, you can still get into a deadly embrace. eg: process A thread 1 takes read lock on own mmap_lock process A thread 2 calls mmap, blocks taking write lock process B thread 1 takes page fault, read lock on own mmap lock process B thread 2 calls mmap, blocks taking write lock process A thread 1 blocks taking read lock on process B process B thread 1 blocks taking read lock on process A Now all four threads are blocked waiting for each other." Regardless using pagefault_disable() ensures that no matter what locking implementation is used a deadlock will not occur. Add an explicit pagefault_disable() and a big comment to explain this for future souls looking at this code. [1] https://lore.kernel.org/all/Y1MymJ%2FINb45AdaY@iweiny-desk3/ [2] https://lore.kernel.org/lkml/Y1bXBtGTCym77%2FoD@casper.infradead.org/ Link: https://lkml.kernel.org/r/20221025220108.2366043-1-ira.weiny@intel.com Link: https://lore.kernel.org/r/202210211215.9dc6efb5-yujie.liu@intel.com Fixes: 7a7256d5f512 ("shmem: convert shmem_mfill_atomic_pte() to use a folio") Signed-off-by: Ira Weiny <ira.weiny@intel.com> Reported-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reported-by: kernel test robot <yujie.liu@intel.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Peter Xu <peterx@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* treewide: use get_random_u32() when possibleJason A. Donenfeld2022-10-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | The prandom_u32() function has been a deprecated inline wrapper around get_random_u32() for several releases now, and compiles down to the exact same code. Replace the deprecated wrapper with a direct call to the real function. The same also applies to get_random_int(), which is just a wrapper around get_random_u32(). This was done as a basic find and replace. Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 Acked-by: Toke Høiland-Jørgensen <toke@toke.dk> # for sch_cake Acked-by: Chuck Lever <chuck.lever@oracle.com> # for nfsd Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> # for thunderbolt Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs Acked-by: Helge Deller <deller@gmx.de> # for parisc Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* Merge tag 'pull-tmpfile' of ↵Linus Torvalds2022-10-101-3/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs tmpfile updates from Al Viro: "Miklos' ->tmpfile() signature change; pass an unopened struct file to it, let it open the damn thing. Allows to add tmpfile support to FUSE" * tag 'pull-tmpfile' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fuse: implement ->tmpfile() vfs: open inside ->tmpfile() vfs: move open right after ->tmpfile() vfs: make vfs_tmpfile() static ovl: use vfs_tmpfile_open() helper cachefiles: use vfs_tmpfile_open() helper cachefiles: only pass inode to *mark_inode_inuse() helpers cachefiles: tmpfile error handling cleanup hugetlbfs: cleanup mknod and tmpfile vfs: add vfs_tmpfile_open() helper
| * vfs: open inside ->tmpfile()Miklos Szeredi2022-09-241-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is in preparation for adding tmpfile support to fuse, which requires that the tmpfile creation and opening are done as a single operation. Replace the 'struct dentry *' argument of i_op->tmpfile with 'struct file *'. Call finish_open_simple() as the last thing in ->tmpfile() instances (may be omitted in the error case). Change d_tmpfile() argument to 'struct file *' as well to make callers more readable. Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
* | mm/shmem: add flag to enforce shmem THP in hugepage_vma_check()Zach O'Keefe2022-10-031-8/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "mm: add file/shmem support to MADV_COLLAPSE", v4. This series builds on top of the previous "mm: userspace hugepage collapse" series which introduced the MADV_COLLAPSE madvise mode and added support for private, anonymous mappings[2], by adding support for file and shmem backed memory to CONFIG_READ_ONLY_THP_FOR_FS=y kernels. File and shmem support have been added with effort to align with existing MADV_COLLAPSE semantics and policy decisions[3]. Collapse of shmem-backed memory ignores kernel-guiding directives and heuristics including all sysfs settings (transparent_hugepage/shmem_enabled), and tmpfs huge= mount options (shmem always supports large folios). Like anonymous mappings, on successful return of MADV_COLLAPSE on file/shmem memory, the contents of memory mapped by the addresses provided will be synchronously pmd-mapped THPs. This functionality unlocks two important uses: (1) Immediately back executable text by THPs. Current support provided by CONFIG_READ_ONLY_THP_FOR_FS may take a long time on a large system which might impair services from serving at their full rated load after (re)starting. Tricks like mremap(2)'ing text onto anonymous memory to immediately realize iTLB performance prevents page sharing and demand paging, both of which increase steady state memory footprint. Now, we can have the best of both worlds: Peak upfront performance and lower RAM footprints. (2) userfaultfd-based live migration of virtual machines satisfy UFFD faults by fetching native-sized pages over the network (to avoid latency of transferring an entire hugepage). However, after guest memory has been fully copied to the new host, MADV_COLLAPSE can be used to immediately increase guest performance. khugepaged has received a small improvement by association and can now detect and collapse pte-mapped THPs. However, there is still work to be done along the file collapse path. Compound pages of arbitrary order still needs to be supported and THP collapse needs to be converted to using folios in general. Eventually, we'd like to move away from the read-only and executable-mapped constraints currently imposed on eligible files and support any inode claiming huge folio support. That said, I think the series as-is covers enough to claim that MADV_COLLAPSE supports file/shmem memory. Patches 1-3 Implement the guts of the series. Patch 4 Is a tracepoint for debugging. Patches 5-9 Refactor existing khugepaged selftests to work with new memory types + new collapse tests. Patch 10 Adds a userfaultfd selftest mode to mimic a functional test of UFFDIO_REGISTER_MODE_MINOR+MADV_COLLAPSE live migration. (v4 note: "userfaultfd shmem" selftest is failing as of Sep 22 mm-unstable) [1] https://lore.kernel.org/linux-mm/YyiK8YvVcrtZo0z3@google.com/ [2] https://lore.kernel.org/linux-mm/20220706235936.2197195-1-zokeefe@google.com/ [3] https://lore.kernel.org/linux-mm/YtBmhaiPHUTkJml8@google.com/ [4] https://lore.kernel.org/linux-mm/20220922222731.1124481-1-zokeefe@google.com/ [5] https://lore.kernel.org/linux-mm/20220922184651.1016461-1-zokeefe@google.com/ This patch (of 10): Extend 'mm/thp: add flag to enforce sysfs THP in hugepage_vma_check()' to shmem, allowing callers to ignore /sys/kernel/transparent_hugepage/shmem_enabled and tmpfs huge= mount. This is intended to be used by MADV_COLLAPSE, and the rationale is analogous to the anon/file case: MADV_COLLAPSE is not coupled to directives that advise the kernel's decisions on when THPs should be considered eligible. shmem/tmpfs always claims large folio support, regardless of sysfs or mount options. [shy828301@gmail.com: test shmem_huge_force explicitly] Link: https://lore.kernel.org/linux-mm/CAHbLzko3A5-TpS0BgBeKkx5cuOkWgLvWXQH=TdgW-baO4rPtdg@mail.gmail.com/ Link: https://lkml.kernel.org/r/20220922224046.1143204-1-zokeefe@google.com Link: https://lkml.kernel.org/r/20220907144521.3115321-2-zokeefe@google.com Link: https://lkml.kernel.org/r/20220922224046.1143204-2-zokeefe@google.com Signed-off-by: Zach O'Keefe <zokeefe@google.com> Reviewed-by: Yang Shi <shy828301@gmail.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Chris Kennelly <ckennelly@google.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Houghton <jthoughton@google.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Peter Xu <peterx@redhat.com> Cc: Rongwei Wang <rongwei.wang@linux.alibaba.com> Cc: SeongJae Park <sj@kernel.org> Cc: Song Liu <songliubraving@fb.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | tmpfs: add support for an i_version counterJeff Layton2022-10-031-3/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | NFSv4 mandates a change attribute to avoid problems with timestamp granularity, which Linux implements using the i_version counter. This is particularly important when the underlying filesystem is fast. Give tmpfs an i_version counter. Since it doesn't have to be persistent, we can just turn on SB_I_VERSION and sprinkle some inode_inc_iversion calls in the right places. Also, while there is no formal spec for xattrs, most implementations update the ctime on setxattr. Fix shmem_xattr_handler_set to update the ctime and bump the i_version appropriately. Link: https://lkml.kernel.org/r/20220909130031.15477-1-jlayton@kernel.org Signed-off-by: Jeff Layton <jlayton@kernel.org> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: remove shmem_getpage()Matthew Wilcox (Oracle)2022-10-031-14/+1
| | | | | | | | | | | | | | | | | | With all callers removed, remove this wrapper function. The flags are now mysteriously called SGP, but I think we can live with that. Link: https://lkml.kernel.org/r/20220902194653.1739778-34-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | khugepaged: call shmem_get_folio()Matthew Wilcox (Oracle)2022-10-031-2/+2
| | | | | | | | | | | | | | | | | | shmem_getpage() is being removed, so call its replacement and find the precise page ourselves. Link: https://lkml.kernel.org/r/20220902194653.1739778-32-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: convert shmem_get_link() to use a folioMatthew Wilcox (Oracle)2022-10-031-16/+17
| | | | | | | | | | | | | | | | | | Symlinks will never use a large folio, but using the folio API removes a lot of unnecessary folio->page->folio conversions. Link: https://lkml.kernel.org/r/20220902194653.1739778-31-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: convert shmem_symlink() to use a folioMatthew Wilcox (Oracle)2022-10-031-7/+7
| | | | | | | | | | | | | | | | | | While symlinks will always be < PAGE_SIZE, using the folio APIs gets rid of unnecessary calls to compound_head(). Link: https://lkml.kernel.org/r/20220902194653.1739778-30-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: convert shmem_fallocate() to use a folioMatthew Wilcox (Oracle)2022-10-031-19/+17
| | | | | | | | | | | | | | | | | | | | Call shmem_get_folio() and use the folio APIs instead of the page APIs. Saves several calls to compound_head() and removes assumptions about the size of a large folio. Link: https://lkml.kernel.org/r/20220902194653.1739778-29-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: convert shmem_file_read_iter() to use shmem_get_folio()Matthew Wilcox (Oracle)2022-10-031-9/+11
| | | | | | | | | | | | | | | | Use a folio throughout, saving five calls to compound_head(). Link: https://lkml.kernel.org/r/20220902194653.1739778-28-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: convert shmem_write_begin() to use shmem_get_folio()Matthew Wilcox (Oracle)2022-10-031-3/+5
| | | | | | | | | | | | | | | | | | Use a folio throughout this function, saving a couple of calls to compound_head(). Link: https://lkml.kernel.org/r/20220902194653.1739778-27-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: convert shmem_get_partial_folio() to use shmem_get_folio()Matthew Wilcox (Oracle)2022-10-031-5/+4
| | | | | | | | | | | | | | | | Get rid of an unnecessary folio->page->folio conversion. Link: https://lkml.kernel.org/r/20220902194653.1739778-26-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: add shmem_get_folio()Matthew Wilcox (Oracle)2022-10-031-13/+10
| | | | | | | | | | | | | | | | | | With no remaining callers of shmem_getpage_gfp(), add shmem_get_folio() and reimplement shmem_getpage() as a call to shmem_get_folio(). Link: https://lkml.kernel.org/r/20220902194653.1739778-25-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: convert shmem_read_mapping_page_gfp() to use shmem_get_folio_gfp()Matthew Wilcox (Oracle)2022-10-031-3/+5
| | | | | | | | | | | | | | | | Saves a couple of calls to compound_head(). Link: https://lkml.kernel.org/r/20220902194653.1739778-24-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: convert shmem_fault() to use shmem_get_folio_gfp()Matthew Wilcox (Oracle)2022-10-031-1/+4
| | | | | | | | | | | | | | | | | | | | | | No particular advantage for this function, but necessary to remove shmem_getpage_gfp(). [hughd@google.com: fix crash] Link: https://lkml.kernel.org/r/7693a84-bdc2-27b5-2695-d0fe8566571f@google.com Link: https://lkml.kernel.org/r/20220902194653.1739778-23-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: convert shmem_getpage_gfp() to shmem_get_folio_gfp()Matthew Wilcox (Oracle)2022-10-031-29/+41
| | | | | | | | | | | | | | | | Add a shmem_getpage_gfp() wrapper for compatibility with current users. Link: https://lkml.kernel.org/r/20220902194653.1739778-22-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: eliminate struct page from shmem_swapin_folio()Matthew Wilcox (Oracle)2022-10-031-8/+8
| | | | | | | | | | | | | | | | | | Convert shmem_swapin() to return a folio and use swap_cache_get_folio(), removing all uses of struct page in this function. Link: https://lkml.kernel.org/r/20220902194653.1739778-21-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: convert shmem_replace_page() to shmem_replace_folio()Matthew Wilcox (Oracle)2022-10-031-5/+4
| | | | | | | | | | | | | | | | | | The caller has a folio, so convert the calling convention and rename the function. Link: https://lkml.kernel.org/r/20220902194653.1739778-19-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: convert shmem_mfill_atomic_pte() to use a folioMatthew Wilcox (Oracle)2022-10-031-26/+19
| | | | | | | | | | | | | | | | | | | | Assert that this is a single-page folio as there are several assumptions in here that it's exactly PAGE_SIZE bytes large. Saves several calls to compound_head() and removes the last caller of shmem_alloc_page(). Link: https://lkml.kernel.org/r/20220902194653.1739778-18-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | mm/swap: convert put_swap_page() to put_swap_folio()Matthew Wilcox (Oracle)2022-10-031-1/+1
| | | | | | | | | | | | | | | | With all callers now using a folio, we can convert this function. Link: https://lkml.kernel.org/r/20220902194653.1739778-14-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | mm/swap: convert add_to_swap_cache() to take a folioMatthew Wilcox (Oracle)2022-10-031-1/+1
| | | | | | | | | | | | | | | | | | With all callers using folios, we can convert add_to_swap_cache() to take a folio and use it throughout. Link: https://lkml.kernel.org/r/20220902194653.1739778-13-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: convert shmem_replace_page() to use folios throughoutMatthew Wilcox (Oracle)2022-10-031-35/+32
| | | | | | | | | | | | | | | | | | | | | | | | Introduce folio_set_swap_entry() to abstract how both folio->private and swp_entry_t work. Use swap_address_space() directly instead of indirecting through folio_mapping(). Include an assertion that the old folio is not large as we only allocate a single-page folio to replace it. Use folio_put_refs() instead of calling folio_put() twice. Link: https://lkml.kernel.org/r/20220902194653.1739778-9-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: convert shmem_delete_from_page_cache() to take a folioMatthew Wilcox (Oracle)2022-10-031-12/+11
| | | | | | | | | | | | | | | | | | Remove the assertion that the page is not Compound as this function now handles large folios correctly. Link: https://lkml.kernel.org/r/20220902194653.1739778-8-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | shmem: convert shmem_writepage() to use a folio throughoutMatthew Wilcox (Oracle)2022-10-031-23/+24
| | | | | | | | | | | | | | | | | | | | Even though we will split any large folio that comes in, write the code to handle large folios so as to not leave a trap for whoever tries to handle large folios in the swap cache. Link: https://lkml.kernel.org/r/20220902194653.1739778-7-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | mm: add split_folio()Matthew Wilcox (Oracle)2022-10-031-1/+1
|/ | | | | | | | | This wrapper removes a need to use split_huge_page(&folio->page). Convert two callers. Link: https://lkml.kernel.org/r/20220902194653.1739778-5-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* shmem: update folio if shmem_replace_page() updates the pageMatthew Wilcox (Oracle)2022-08-281-0/+1
| | | | | | | | | | | | | | | | | | | | If we allocate a new page, we need to make sure that our folio matches that new page. If we do end up in this code path, we store the wrong page in the shmem inode's page cache, and I would rather imagine that data corruption ensues. This will be solved by changing shmem_replace_page() to shmem_replace_folio(), but this is the minimal fix. Link: https://lkml.kernel.org/r/20220730042518.1264767-1-willy@infradead.org Fixes: da08e9b79323 ("mm/shmem: convert shmem_swapin_page() to shmem_swapin_folio()") Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: William Kucharski <william.kucharski@oracle.com> Cc: Hugh Dickins <hughd@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* mm/shmem: shmem_replace_page() remember NR_SHMEMHugh Dickins2022-08-201-0/+2
| | | | | | | | | | | | | | Elsewhere, NR_SHMEM is updated at the same time as shmem NR_FILE_PAGES; but shmem_replace_page() was forgetting to do that - so NR_SHMEM stats could grow too big or too small, in those unusual cases when it's used. Link: https://lkml.kernel.org/r/cec7c09d-5874-e160-ada6-6e10ee48784@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Radoslaw Burny <rburny@google.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* mm/shmem: tmpfs fallocate use file_modified()Hugh Dickins2022-08-201-1/+2
| | | | | | | | | | | | | | | | 5.18 fixed the btrfs and ext4 fallocates to use file_modified(), as xfs was already doing, to drop privileges: and fstests generic/{683,684,688} expect this. There's no need to argue over keep-size allocation (which could just update ctime): fix shmem_fallocate() to behave the same way. Link: https://lkml.kernel.org/r/39c5e62-4896-7795-c0a0-f79c50d4909@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Christian Brauner (Microsoft) <brauner@kernel.org> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Radoslaw Burny <rburny@google.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* mm/shmem: fix chattr fsflags support in tmpfsHugh Dickins2022-08-201-23/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | ext[234] have always allowed unimplemented chattr flags to be set, but other filesystems have tended to be stricter. Follow the stricter approach for tmpfs: I don't want to have to explain why csu attributes don't actually work, and we won't need to update the chattr(1) manpage; and it's never wrong to start off strict, relaxing later if persuaded. Allow only a (append only) i (immutable) A (no atime) and d (no dump). Although lsattr showed 'A' inherited, the NOATIME behavior was not being inherited: because nothing sync'ed FS_NOATIME_FL to S_NOATIME. Add shmem_set_inode_flags() to sync the flags, using inode_set_flags() to avoid that instant of lost immutablility during fileattr_set(). But that change switched generic/079 from passing to failing: because FS_IMMUTABLE_FL and FS_APPEND_FL had been unconventionally included in the INHERITED fsflags: remove them and generic/079 is back to passing. Link: https://lkml.kernel.org/r/2961dcb0-ddf3-b9f0-3268-12a4ff996856@google.com Fixes: e408e695f5f1 ("mm/shmem: support FS_IOC_[SG]ETFLAGS in tmpfs") Signed-off-by: Hugh Dickins <hughd@google.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Radoslaw Burny <rburny@google.com> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* Merge tag 'pull-work.iov_iter-rebased' of ↵Linus Torvalds2022-08-081-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more iov_iter updates from Al Viro: - more new_sync_{read,write}() speedups - ITER_UBUF introduction - ITER_PIPE cleanups - unification of iov_iter_get_pages/iov_iter_get_pages_alloc and switching them to advancing semantics - making ITER_PIPE take high-order pages without splitting them - handling copy_page_from_iter() for high-order pages properly * tag 'pull-work.iov_iter-rebased' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (32 commits) fix copy_page_from_iter() for compound destinations hugetlbfs: copy_page_to_iter() can deal with compound pages copy_page_to_iter(): don't split high-order page in case of ITER_PIPE expand those iov_iter_advance()... pipe_get_pages(): switch to append_pipe() get rid of non-advancing variants ceph: switch the last caller of iov_iter_get_pages_alloc() 9p: convert to advancing variant of iov_iter_get_pages_alloc() af_alg_make_sg(): switch to advancing variant of iov_iter_get_pages() iter_to_pipe(): switch to advancing variant of iov_iter_get_pages() block: convert to advancing variants of iov_iter_get_pages{,_alloc}() iov_iter: advancing variants of iov_iter_get_pages{,_alloc}() iov_iter: saner helper for page array allocation fold __pipe_get_pages() into pipe_get_pages() ITER_XARRAY: don't open-code DIV_ROUND_UP() unify the rest of iov_iter_get_pages()/iov_iter_get_pages_alloc() guts unify xarray_get_pages() and xarray_get_pages_alloc() unify pipe_get_pages() and pipe_get_pages_alloc() iov_iter_get_pages(): sanity-check arguments iov_iter_get_pages_alloc(): lift freeing pages array on failure exits into wrapper ...
| * new iov_iter flavour - ITER_UBUFAl Viro2022-08-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Equivalent of single-segment iovec. Initialized by iov_iter_ubuf(), checked for by iter_is_ubuf(), otherwise behaves like ITER_IOVEC ones. We are going to expose the things like ->write_iter() et.al. to those in subsequent commits. New predicate (user_backed_iter()) that is true for ITER_IOVEC and ITER_UBUF; places like direct-IO handling should use that for checking that pages we modify after getting them from iov_iter_get_pages() would need to be dirtied. DO NOT assume that replacing iter_is_iovec() with user_backed_iter() will solve all problems - there's code that uses iter_is_iovec() to decide how to poke around in iov_iter guts and for that the predicate replacement obviously won't suffice. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge tag 'mm-stable-2022-08-03' of ↵Linus Torvalds2022-08-051-8/+70
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Most of the MM queue. A few things are still pending. Liam's maple tree rework didn't make it. This has resulted in a few other minor patch series being held over for next time. Multi-gen LRU still isn't merged as we were waiting for mapletree to stabilize. The current plan is to merge MGLRU into -mm soon and to later reintroduce mapletree, with a view to hopefully getting both into 6.1-rc1. Summary: - The usual batches of cleanups from Baoquan He, Muchun Song, Miaohe Lin, Yang Shi, Anshuman Khandual and Mike Rapoport - Some kmemleak fixes from Patrick Wang and Waiman Long - DAMON updates from SeongJae Park - memcg debug/visibility work from Roman Gushchin - vmalloc speedup from Uladzislau Rezki - more folio conversion work from Matthew Wilcox - enhancements for coherent device memory mapping from Alex Sierra - addition of shared pages tracking and CoW support for fsdax, from Shiyang Ruan - hugetlb optimizations from Mike Kravetz - Mel Gorman has contributed some pagealloc changes to improve latency and realtime behaviour. - mprotect soft-dirty checking has been improved by Peter Xu - Many other singleton patches all over the place" [ XFS merge from hell as per Darrick Wong in https://lore.kernel.org/all/YshKnxb4VwXycPO8@magnolia/ ] * tag 'mm-stable-2022-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (282 commits) tools/testing/selftests/vm/hmm-tests.c: fix build mm: Kconfig: fix typo mm: memory-failure: convert to pr_fmt() mm: use is_zone_movable_page() helper hugetlbfs: fix inaccurate comment in hugetlbfs_statfs() hugetlbfs: cleanup some comments in inode.c hugetlbfs: remove unneeded header file hugetlbfs: remove unneeded hugetlbfs_ops forward declaration hugetlbfs: use helper macro SZ_1{K,M} mm: cleanup is_highmem() mm/hmm: add a test for cross device private faults selftests: add soft-dirty into run_vmtests.sh selftests: soft-dirty: add test for mprotect mm/mprotect: fix soft-dirty check in can_change_pte_writable() mm: memcontrol: fix potential oom_lock recursion deadlock mm/gup.c: fix formatting in check_and_migrate_movable_page() xfs: fail dax mount if reflink is enabled on a partition mm/memcontrol.c: remove the redundant updating of stats_flush_threshold userfaultfd: don't fail on unrecognized features hugetlb_cgroup: fix wrong hugetlb cgroup numa stat ...
| * mm/shmem: support FS_IOC_[SG]ETFLAGS in tmpfsTheodore Ts'o2022-07-291-1/+63
| | | | | | | | | | | | | | | | | | | | | | This allows userspace to set flags like FS_APPEND_FL, FS_IMMUTABLE_FL, FS_NODUMP_FL, etc., like all other standard Linux file systems. [akpm@linux-foundation.org: fix CONFIG_TMPFS_XATTR=n warnings] Link: https://lkml.kernel.org/r/20220715015912.2560575-1-tytso@mit.edu Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| * mm/swap: convert delete_from_swap_cache() to take a folioMatthew Wilcox (Oracle)2022-07-031-2/+2
| | | | | | | | | | | | | | | | All but one caller already has a folio, so convert it to use a folio. Link: https://lkml.kernel.org/r/20220617175020.717127-22-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>