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linux/tools/testing/vma/vma_internal.h

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tools: add skeleton code for userland testing of VMA logic Establish a new userland VMA unit testing implementation under tools/testing which utilises existing logic providing maple tree support in userland utilising the now-shared code previously exclusive to radix tree testing. This provides fundamental VMA operations whose API is defined in mm/vma.h, while stubbing out superfluous functionality. This exists as a proof-of-concept, with the test implementation functional and sufficient to allow userland compilation of vma.c, but containing only cursory tests to demonstrate basic functionality. Link: https://lkml.kernel.org/r/533ffa2eec771cbe6b387dd049a7f128a53eb616.1722251717.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Tested-by: SeongJae Park <sj@kernel.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: Christian Brauner <brauner@kernel.org> Cc: David Gow <davidgow@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Jan Kara <jack@suse.cz> Cc: Kees Cook <kees@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Rae Moar <rmoar@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Pengfei Xu <pengfei.xu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-29 12:50:41 +01:00
tools/testing/vma: separate out vma_internal.h into logical headers The vma_internal.h file is becoming entirely unmanageable. It combines duplicated kernel implementation logic that needs to be kept in-sync with the kernel, stubbed out declarations that we simply ignore for testing purposes and custom logic added to aid testing. If we separate each of the three things into separate headers it makes things far more manageable, so do so: * include/stubs.h contains the stubbed declarations, * include/dup.h contains the duplicated kernel declarations, and * include/custom.h contains declarations customised for testing. [lorenzo.stoakes@oracle.com: avoid a duplicate struct define] Link: https://lkml.kernel.org/r/1e032732-61c3-485c-9aa7-6a09016fefc1@lucifer.local Link: https://lkml.kernel.org/r/dd57baf5b5986cb96a167150ac712cbe804b63ee.1769097829.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Cc: Damien Le Moal <dlemoal@kernel.org> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Yury Norov <ynorov@nvidia.com> Cc: Chris Mason <clm@fb.com> Cc: Pedro Falcato <pfalcato@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-22 16:06:21 +00:00
tools: add skeleton code for userland testing of VMA logic Establish a new userland VMA unit testing implementation under tools/testing which utilises existing logic providing maple tree support in userland utilising the now-shared code previously exclusive to radix tree testing. This provides fundamental VMA operations whose API is defined in mm/vma.h, while stubbing out superfluous functionality. This exists as a proof-of-concept, with the test implementation functional and sufficient to allow userland compilation of vma.c, but containing only cursory tests to demonstrate basic functionality. Link: https://lkml.kernel.org/r/533ffa2eec771cbe6b387dd049a7f128a53eb616.1722251717.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Tested-by: SeongJae Park <sj@kernel.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: Christian Brauner <brauner@kernel.org> Cc: David Gow <davidgow@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Jan Kara <jack@suse.cz> Cc: Kees Cook <kees@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Rae Moar <rmoar@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Pengfei Xu <pengfei.xu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-29 12:50:41 +01:00
mm: add basic VMA flag operation helper functions Now we have the mk_vma_flags() macro helper which permits easy specification of any number of VMA flags, add helper functions which operate with vma_flags_t parameters. This patch provides vma_flags_test[_mask](), vma_flags_set[_mask]() and vma_flags_clear[_mask]() respectively testing, setting and clearing flags with the _mask variants accepting vma_flag_t parameters, and the non-mask variants implemented as macros which accept a list of flags. This allows us to trivially test/set/clear aggregate VMA flag values as necessary, for instance: if (vma_flags_test(&flags, VMA_READ_BIT, VMA_WRITE_BIT)) goto readwrite; vma_flags_set(&flags, VMA_READ_BIT, VMA_WRITE_BIT); vma_flags_clear(&flags, VMA_READ_BIT, VMA_WRITE_BIT); We also add a function for testing that ALL flags are set for convenience, e.g.: if (vma_flags_test_all(&flags, VMA_READ_BIT, VMA_MAYREAD_BIT)) { /* Both READ and MAYREAD flags set */ ... } The compiler generates optimal assembly for each such that they behave as if the caller were setting the bitmap flags manually. This is important for e.g. drivers which manipulate flag values rather than a VMA's specific flag values. We also add helpers for testing, setting and clearing flags for VMA's and VMA descriptors to reduce boilerplate. Also add the EMPTY_VMA_FLAGS define to aid initialisation of empty flags. Finally, update the userland VMA tests to add the helpers there so they can be utilised as part of userland testing. Link: https://lkml.kernel.org/r/885d4897d67a6a57c0b07fa182a7055ad752df11.1769097829.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Cc: Damien Le Moal <dlemoal@kernel.org> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Yury Norov <ynorov@nvidia.com> Cc: Chris Mason <clm@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-22 16:06:14 +00:00
tools: testing: use existing atomic.h for vma/maple tests The shared userspace logic used for unit-testing maple tree and VMA code currently has its own replacements for atomics helpers. This is not needed as the necessary APIs already have userspace implementations in the tools tree. Switching over to that allows deleting a bit of code. Note that the implementation is different; while the version being deleted here is implemented using liburcu, the existing version in tools uses either x86 asm or compiler builtins. It's assumed that both are equally likely to be correct. The tools tree's version of atomic_t is a struct type while the version being deleted was just a typedef of an integer. This means it's no longer valid to call __sync_bool_compare_and_swap() directly on it. One option would be to just peek into the struct and call it on the field, but it seems a little cleaner to just use the corresponding atomic.h API whic has been added recently. Now the fake mapping_map_writable() is copied from the real one. Link: https://lkml.kernel.org/r/20250828-b4-vma-no-atomic-h-v2-4-02d146a58ed2@google.com Signed-off-by: Brendan Jackman <jackmanb@google.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Cc: Jann Horn <jannh@google.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-08-28 12:28:01 +00:00
mm: add basic VMA flag operation helper functions Now we have the mk_vma_flags() macro helper which permits easy specification of any number of VMA flags, add helper functions which operate with vma_flags_t parameters. This patch provides vma_flags_test[_mask](), vma_flags_set[_mask]() and vma_flags_clear[_mask]() respectively testing, setting and clearing flags with the _mask variants accepting vma_flag_t parameters, and the non-mask variants implemented as macros which accept a list of flags. This allows us to trivially test/set/clear aggregate VMA flag values as necessary, for instance: if (vma_flags_test(&flags, VMA_READ_BIT, VMA_WRITE_BIT)) goto readwrite; vma_flags_set(&flags, VMA_READ_BIT, VMA_WRITE_BIT); vma_flags_clear(&flags, VMA_READ_BIT, VMA_WRITE_BIT); We also add a function for testing that ALL flags are set for convenience, e.g.: if (vma_flags_test_all(&flags, VMA_READ_BIT, VMA_MAYREAD_BIT)) { /* Both READ and MAYREAD flags set */ ... } The compiler generates optimal assembly for each such that they behave as if the caller were setting the bitmap flags manually. This is important for e.g. drivers which manipulate flag values rather than a VMA's specific flag values. We also add helpers for testing, setting and clearing flags for VMA's and VMA descriptors to reduce boilerplate. Also add the EMPTY_VMA_FLAGS define to aid initialisation of empty flags. Finally, update the userland VMA tests to add the helpers there so they can be utilised as part of userland testing. Link: https://lkml.kernel.org/r/885d4897d67a6a57c0b07fa182a7055ad752df11.1769097829.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Cc: Damien Le Moal <dlemoal@kernel.org> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Yury Norov <ynorov@nvidia.com> Cc: Chris Mason <clm@fb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-22 16:06:14 +00:00
tools: add skeleton code for userland testing of VMA logic Establish a new userland VMA unit testing implementation under tools/testing which utilises existing logic providing maple tree support in userland utilising the now-shared code previously exclusive to radix tree testing. This provides fundamental VMA operations whose API is defined in mm/vma.h, while stubbing out superfluous functionality. This exists as a proof-of-concept, with the test implementation functional and sufficient to allow userland compilation of vma.c, but containing only cursory tests to demonstrate basic functionality. Link: https://lkml.kernel.org/r/533ffa2eec771cbe6b387dd049a7f128a53eb616.1722251717.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Tested-by: SeongJae Park <sj@kernel.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: Christian Brauner <brauner@kernel.org> Cc: David Gow <davidgow@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Jan Kara <jack@suse.cz> Cc: Kees Cook <kees@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Rae Moar <rmoar@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Pengfei Xu <pengfei.xu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-29 12:50:41 +01:00
mm: replace vm_lock and detached flag with a reference count rw_semaphore is a sizable structure of 40 bytes and consumes considerable space for each vm_area_struct. However vma_lock has two important specifics which can be used to replace rw_semaphore with a simpler structure: 1. Readers never wait. They try to take the vma_lock and fall back to mmap_lock if that fails. 2. Only one writer at a time will ever try to write-lock a vma_lock because writers first take mmap_lock in write mode. Because of these requirements, full rw_semaphore functionality is not needed and we can replace rw_semaphore and the vma->detached flag with a refcount (vm_refcnt). When vma is in detached state, vm_refcnt is 0 and only a call to vma_mark_attached() can take it out of this state. Note that unlike before, now we enforce both vma_mark_attached() and vma_mark_detached() to be done only after vma has been write-locked. vma_mark_attached() changes vm_refcnt to 1 to indicate that it has been attached to the vma tree. When a reader takes read lock, it increments vm_refcnt, unless the top usable bit of vm_refcnt (0x40000000) is set, indicating presence of a writer. When writer takes write lock, it sets the top usable bit to indicate its presence. If there are readers, writer will wait using newly introduced mm->vma_writer_wait. Since all writers take mmap_lock in write mode first, there can be only one writer at a time. The last reader to release the lock will signal the writer to wake up. refcount might overflow if there are many competing readers, in which case read-locking will fail. Readers are expected to handle such failures. In summary: 1. all readers increment the vm_refcnt; 2. writer sets top usable (writer) bit of vm_refcnt; 3. readers cannot increment the vm_refcnt if the writer bit is set; 4. in the presence of readers, writer must wait for the vm_refcnt to drop to 1 (plus the VMA_LOCK_OFFSET writer bit), indicating an attached vma with no readers; 5. vm_refcnt overflow is handled by the readers. While this vm_lock replacement does not yet result in a smaller vm_area_struct (it stays at 256 bytes due to cacheline alignment), it allows for further size optimization by structure member regrouping to bring the size of vm_area_struct below 192 bytes. [surenb@google.com: fix a crash due to vma_end_read() that should have been removed] Link: https://lkml.kernel.org/r/20250220200208.323769-1-surenb@google.com Link: https://lkml.kernel.org/r/20250213224655.1680278-13-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Suggested-by: Matthew Wilcox <willy@infradead.org> Tested-by: Shivank Garg <shivankg@amd.com> Link: https://lkml.kernel.org/r/5e19ec93-8307-47c2-bb13-3ddf7150624e@amd.com Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Christian Brauner <brauner@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Hugh Dickins <hughd@google.com> Cc: Jann Horn <jannh@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Klara Modin <klarasmodin@gmail.com> Cc: Liam R. Howlett <Liam.Howlett@Oracle.com> Cc: Lokesh Gidra <lokeshgidra@google.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Mateusz Guzik <mjguzik@gmail.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Minchan Kim <minchan@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: "Paul E . McKenney" <paulmck@kernel.org> Cc: Peter Xu <peterx@redhat.com> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Sourav Panda <souravpanda@google.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Will Deacon <will@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-02-13 14:46:49 -08:00
tools/testing: Add support for changes to slab for sheaves The slab changes for sheaves requires more effort in the testing code. Unite all the kmem_cache work into the tools/include slab header for both the vma and maple tree testing. The vma test code also requires importing more #defines to allow for seamless use of the shared kmem_cache code. This adds the pthread header to the slab header in the tools directory to allow for the pthread_mutex in linux.c. Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reviewed-by: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
2025-09-03 14:59:53 +02:00
tools: add skeleton code for userland testing of VMA logic Establish a new userland VMA unit testing implementation under tools/testing which utilises existing logic providing maple tree support in userland utilising the now-shared code previously exclusive to radix tree testing. This provides fundamental VMA operations whose API is defined in mm/vma.h, while stubbing out superfluous functionality. This exists as a proof-of-concept, with the test implementation functional and sufficient to allow userland compilation of vma.c, but containing only cursory tests to demonstrate basic functionality. Link: https://lkml.kernel.org/r/533ffa2eec771cbe6b387dd049a7f128a53eb616.1722251717.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Tested-by: SeongJae Park <sj@kernel.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: Christian Brauner <brauner@kernel.org> Cc: David Gow <davidgow@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Jan Kara <jack@suse.cz> Cc: Kees Cook <kees@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Rae Moar <rmoar@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Pengfei Xu <pengfei.xu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-29 12:50:41 +01:00
mm: declare VMA flags by bit Patch series "initial work on making VMA flags a bitmap", v3. We are in the rather silly situation that we are running out of VMA flags as they are currently limited to a system word in size. This leads to absurd situations where we limit features to 64-bit architectures only because we simply do not have the ability to add a flag for 32-bit ones. This is very constraining and leads to hacks or, in the worst case, simply an inability to implement features we want for entirely arbitrary reasons. This also of course gives us something of a Y2K type situation in mm where we might eventually exhaust all of the VMA flags even on 64-bit systems. This series lays the groundwork for getting away from this limitation by establishing VMA flags as a bitmap whose size we can increase in future beyond 64 bits if required. This is necessarily a highly iterative process given the extensive use of VMA flags throughout the kernel, so we start by performing basic steps. Firstly, we declare VMA flags by bit number rather than by value, retaining the VM_xxx fields but in terms of these newly introduced VMA_xxx_BIT fields. While we are here, we use sparse annotations to ensure that, when dealing with VMA bit number parameters, we cannot be passed values which are not declared as such - providing some useful type safety. We then introduce an opaque VMA flag type, much like the opaque mm_struct flag type introduced in commit bb6525f2f8c4 ("mm: add bitmap mm->flags field"), which we establish in union with vma->vm_flags (but still set at system word size meaning there is no functional or data type size change). We update the vm_flags_xxx() helpers to use this new bitmap, introducing sensible helpers to do so. This series lays the foundation for further work to expand the use of bitmap VMA flags and eventually eliminate these arbitrary restrictions. This patch (of 4): In order to lay the groundwork for VMA flags being a bitmap rather than a system word in size, we need to be able to consistently refer to VMA flags by bit number rather than value. Take this opportunity to do so in an enum which we which is additionally useful for tooling to extract metadata from. This additionally makes it very clear which bits are being used for what at a glance. We use the VMA_ prefix for the bit values as it is logical to do so since these reference VMAs. We consistently suffix with _BIT to make it clear what the values refer to. We declare bit values even when the flags that use them would not be enabled by config options as this is simply clearer and clearly defines what bit numbers are used for what, at no additional cost. We declare a sparse-bitwise type vma_flag_t which ensures that users can't pass around invalid VMA flags by accident and prepares for future work towards VMA flags being a bitmap where we want to ensure bit values are type safe. To make life easier, we declare some macro helpers - DECLARE_VMA_BIT() allows us to avoid duplication in the enum bit number declarations (and maintaining the sparse __bitwise attribute), and INIT_VM_FLAG() is used to assist with declaration of flags. Unfortunately we can't declare both in the enum, as we run into issue with logic in the kernel requiring that flags are preprocessor definitions, and additionally we cannot have a macro which declares another macro so we must define each flag macro directly. Additionally, update the VMA userland testing vma_internal.h header to include these changes. We also have to fix the parameters to the vma_flag_*_atomic() functions since VMA_MAYBE_GUARD_BIT is now of type vma_flag_t and sparse will complain otherwise. We have to update some rather silly if-deffery found in mm/task_mmu.c which would otherwise break. Finally, we update the rust binding helper as now it cannot auto-detect the flags at all. Link: https://lkml.kernel.org/r/cover.1764064556.git.lorenzo.stoakes@oracle.com Link: https://lkml.kernel.org/r/3a35e5a0bcfa00e84af24cbafc0653e74deda64a.1764064556.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Acked-by: Alice Ryhl <aliceryhl@google.com> [rust] Cc: Alex Gaynor <alex.gaynor@gmail.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Andreas Hindborg <a.hindborg@kernel.org> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: Ben Segall <bsegall@google.com> Cc: Björn Roy Baron <bjorn3_gh@protonmail.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Byungchul Park <byungchul@sk.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chris Li <chrisl@kernel.org> Cc: Danilo Krummrich <dakr@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Dev Jain <dev.jain@arm.com> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Gary Guo <gary@garyguo.net> Cc: Gregory Price <gourry@gourry.net> Cc: "Huang, Ying" <ying.huang@linux.alibaba.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Joshua Hahn <joshua.hahnjy@gmail.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Kairui Song <kasong@tencent.com> Cc: Kees Cook <kees@kernel.org> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Leon Romanovsky <leon@kernel.org> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mathew Brost <matthew.brost@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mel Gorman <mgorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Nico Pache <npache@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Rakie Kim <rakie.kim@sk.com> Cc: Rik van Riel <riel@surriel.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Trevor Gross <tmgross@umich.edu> Cc: Valentin Schneider <vschneid@redhat.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Wei Xu <weixugc@google.com> Cc: xu xin <xu.xin16@zte.com.cn> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-25 10:00:59 +00:00
tools/testing/vma: separate out vma_internal.h into logical headers The vma_internal.h file is becoming entirely unmanageable. It combines duplicated kernel implementation logic that needs to be kept in-sync with the kernel, stubbed out declarations that we simply ignore for testing purposes and custom logic added to aid testing. If we separate each of the three things into separate headers it makes things far more manageable, so do so: * include/stubs.h contains the stubbed declarations, * include/dup.h contains the duplicated kernel declarations, and * include/custom.h contains declarations customised for testing. [lorenzo.stoakes@oracle.com: avoid a duplicate struct define] Link: https://lkml.kernel.org/r/1e032732-61c3-485c-9aa7-6a09016fefc1@lucifer.local Link: https://lkml.kernel.org/r/dd57baf5b5986cb96a167150ac712cbe804b63ee.1769097829.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Cc: Damien Le Moal <dlemoal@kernel.org> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Yury Norov <ynorov@nvidia.com> Cc: Chris Mason <clm@fb.com> Cc: Pedro Falcato <pfalcato@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-22 16:06:21 +00:00
mm: declare VMA flags by bit Patch series "initial work on making VMA flags a bitmap", v3. We are in the rather silly situation that we are running out of VMA flags as they are currently limited to a system word in size. This leads to absurd situations where we limit features to 64-bit architectures only because we simply do not have the ability to add a flag for 32-bit ones. This is very constraining and leads to hacks or, in the worst case, simply an inability to implement features we want for entirely arbitrary reasons. This also of course gives us something of a Y2K type situation in mm where we might eventually exhaust all of the VMA flags even on 64-bit systems. This series lays the groundwork for getting away from this limitation by establishing VMA flags as a bitmap whose size we can increase in future beyond 64 bits if required. This is necessarily a highly iterative process given the extensive use of VMA flags throughout the kernel, so we start by performing basic steps. Firstly, we declare VMA flags by bit number rather than by value, retaining the VM_xxx fields but in terms of these newly introduced VMA_xxx_BIT fields. While we are here, we use sparse annotations to ensure that, when dealing with VMA bit number parameters, we cannot be passed values which are not declared as such - providing some useful type safety. We then introduce an opaque VMA flag type, much like the opaque mm_struct flag type introduced in commit bb6525f2f8c4 ("mm: add bitmap mm->flags field"), which we establish in union with vma->vm_flags (but still set at system word size meaning there is no functional or data type size change). We update the vm_flags_xxx() helpers to use this new bitmap, introducing sensible helpers to do so. This series lays the foundation for further work to expand the use of bitmap VMA flags and eventually eliminate these arbitrary restrictions. This patch (of 4): In order to lay the groundwork for VMA flags being a bitmap rather than a system word in size, we need to be able to consistently refer to VMA flags by bit number rather than value. Take this opportunity to do so in an enum which we which is additionally useful for tooling to extract metadata from. This additionally makes it very clear which bits are being used for what at a glance. We use the VMA_ prefix for the bit values as it is logical to do so since these reference VMAs. We consistently suffix with _BIT to make it clear what the values refer to. We declare bit values even when the flags that use them would not be enabled by config options as this is simply clearer and clearly defines what bit numbers are used for what, at no additional cost. We declare a sparse-bitwise type vma_flag_t which ensures that users can't pass around invalid VMA flags by accident and prepares for future work towards VMA flags being a bitmap where we want to ensure bit values are type safe. To make life easier, we declare some macro helpers - DECLARE_VMA_BIT() allows us to avoid duplication in the enum bit number declarations (and maintaining the sparse __bitwise attribute), and INIT_VM_FLAG() is used to assist with declaration of flags. Unfortunately we can't declare both in the enum, as we run into issue with logic in the kernel requiring that flags are preprocessor definitions, and additionally we cannot have a macro which declares another macro so we must define each flag macro directly. Additionally, update the VMA userland testing vma_internal.h header to include these changes. We also have to fix the parameters to the vma_flag_*_atomic() functions since VMA_MAYBE_GUARD_BIT is now of type vma_flag_t and sparse will complain otherwise. We have to update some rather silly if-deffery found in mm/task_mmu.c which would otherwise break. Finally, we update the rust binding helper as now it cannot auto-detect the flags at all. Link: https://lkml.kernel.org/r/cover.1764064556.git.lorenzo.stoakes@oracle.com Link: https://lkml.kernel.org/r/3a35e5a0bcfa00e84af24cbafc0653e74deda64a.1764064556.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Acked-by: Alice Ryhl <aliceryhl@google.com> [rust] Cc: Alex Gaynor <alex.gaynor@gmail.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Andreas Hindborg <a.hindborg@kernel.org> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: Ben Segall <bsegall@google.com> Cc: Björn Roy Baron <bjorn3_gh@protonmail.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Byungchul Park <byungchul@sk.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chris Li <chrisl@kernel.org> Cc: Danilo Krummrich <dakr@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Dev Jain <dev.jain@arm.com> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Gary Guo <gary@garyguo.net> Cc: Gregory Price <gourry@gourry.net> Cc: "Huang, Ying" <ying.huang@linux.alibaba.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Joshua Hahn <joshua.hahnjy@gmail.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Kairui Song <kasong@tencent.com> Cc: Kees Cook <kees@kernel.org> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Leon Romanovsky <leon@kernel.org> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mathew Brost <matthew.brost@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mel Gorman <mgorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Nico Pache <npache@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Rakie Kim <rakie.kim@sk.com> Cc: Rik van Riel <riel@surriel.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Trevor Gross <tmgross@umich.edu> Cc: Valentin Schneider <vschneid@redhat.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Wei Xu <weixugc@google.com> Cc: xu xin <xu.xin16@zte.com.cn> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-25 10:00:59 +00:00
tools/testing/vma: separate out vma_internal.h into logical headers The vma_internal.h file is becoming entirely unmanageable. It combines duplicated kernel implementation logic that needs to be kept in-sync with the kernel, stubbed out declarations that we simply ignore for testing purposes and custom logic added to aid testing. If we separate each of the three things into separate headers it makes things far more manageable, so do so: * include/stubs.h contains the stubbed declarations, * include/dup.h contains the duplicated kernel declarations, and * include/custom.h contains declarations customised for testing. [lorenzo.stoakes@oracle.com: avoid a duplicate struct define] Link: https://lkml.kernel.org/r/1e032732-61c3-485c-9aa7-6a09016fefc1@lucifer.local Link: https://lkml.kernel.org/r/dd57baf5b5986cb96a167150ac712cbe804b63ee.1769097829.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Cc: Damien Le Moal <dlemoal@kernel.org> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Yury Norov <ynorov@nvidia.com> Cc: Chris Mason <clm@fb.com> Cc: Pedro Falcato <pfalcato@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-22 16:06:21 +00:00
tools/testing/vma: add VMA userland tests for VMA flag functions Now we have the capability to test the new helpers for the bitmap VMA flags in userland, do so. We also update the Makefile such that both VMA (and while we're here) mm_struct flag sizes can be customised on build. We default to 128-bit to enable testing of flags above word size even on 64-bit systems. We add userland tests to ensure that we do not regress VMA flag behaviour with the introduction when using bitmap VMA flags, nor accidentally introduce unexpected results due to for instance higher bit values not being correctly cleared/set. As part of this change, make __mk_vma_flags() a custom function so we can handle specifying invalid VMA bits. This is purposeful so we can have the VMA tests work at lower and higher number of VMA flags without having to duplicate code too much. Link: https://lkml.kernel.org/r/7fe6afe9c8c61e4d3cfc9a2d50a5d24da8528e68.1769097829.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Cc: Damien Le Moal <dlemoal@kernel.org> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Yury Norov <ynorov@nvidia.com> Cc: Chris Mason <clm@fb.com> Cc: Pedro Falcato <pfalcato@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-22 16:06:22 +00:00
mm: replace mm->flags with bitmap entirely and set to 64 bits Now we have updated all users of mm->flags to use the bitmap accessors, repalce it with the bitmap version entirely. We are then able to move to having 64 bits of mm->flags on both 32-bit and 64-bit architectures. We also update the VMA userland tests to ensure that everything remains functional there. No functional changes intended, other than there now being 64 bits of available mm_struct flags. Link: https://lkml.kernel.org/r/e1f6654e016d36c43959764b01355736c5cbcdf8.1755012943.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Acked-by: David Hildenbrand <david@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: Ben Segall <bsegall@google.com> Cc: Borislav Betkov <bp@alien8.de> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dev Jain <dev.jain@arm.com> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Kees Cook <kees@kernel.org> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Mariano Pache <npache@redhat.com> Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org> Cc: Mateusz Guzik <mjguzik@gmail.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mel Gorman <mgorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: Namhyung kim <namhyung@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Valentin Schneider <vschneid@redhat.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: xu xin <xu.xin16@zte.com.cn> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-08-12 16:44:19 +01:00
tools/testing/vma: add VMA userland tests for VMA flag functions Now we have the capability to test the new helpers for the bitmap VMA flags in userland, do so. We also update the Makefile such that both VMA (and while we're here) mm_struct flag sizes can be customised on build. We default to 128-bit to enable testing of flags above word size even on 64-bit systems. We add userland tests to ensure that we do not regress VMA flag behaviour with the introduction when using bitmap VMA flags, nor accidentally introduce unexpected results due to for instance higher bit values not being correctly cleared/set. As part of this change, make __mk_vma_flags() a custom function so we can handle specifying invalid VMA bits. This is purposeful so we can have the VMA tests work at lower and higher number of VMA flags without having to duplicate code too much. Link: https://lkml.kernel.org/r/7fe6afe9c8c61e4d3cfc9a2d50a5d24da8528e68.1769097829.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Cc: Damien Le Moal <dlemoal@kernel.org> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Yury Norov <ynorov@nvidia.com> Cc: Chris Mason <clm@fb.com> Cc: Pedro Falcato <pfalcato@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-22 16:06:22 +00:00
mm: introduce VMA flags bitmap type It is useful to transition to using a bitmap for VMA flags so we can avoid running out of flags, especially for 32-bit kernels which are constrained to 32 flags, necessitating some features to be limited to 64-bit kernels only. By doing so, we remove any constraint on the number of VMA flags moving forwards no matter the platform and can decide in future to extend beyond 64 if required. We start by declaring an opaque types, vma_flags_t (which resembles mm_struct flags of type mm_flags_t), setting it to precisely the same size as vm_flags_t, and place it in union with vm_flags in the VMA declaration. We additionally update struct vm_area_desc equivalently placing the new opaque type in union with vm_flags. This change therefore does not impact the size of struct vm_area_struct or struct vm_area_desc. In order for the change to be iterative and to avoid impacting performance, we designate VM_xxx declared bitmap flag values as those which must exist in the first system word of the VMA flags bitmap. We therefore declare vma_flags_clear_all(), vma_flags_overwrite_word(), vma_flags_overwrite_word(), vma_flags_overwrite_word_once(), vma_flags_set_word() and vma_flags_clear_word() in order to allow us to update the existing vm_flags_*() functions to utilise these helpers. This is a stepping stone towards converting users to the VMA flags bitmap and behaves precisely as before. By doing this, we can eliminate the existing private vma->__vm_flags field in the vma->vm_flags union and replace it with the newly introduced opaque type vma_flags, which we call flags so we refer to the new bitmap field as vma->flags. We update vma_flag_[test, set]_atomic() to account for the change also. We adapt vm_flags_reset_once() to only clear those bits above the first system word providing write-once semantics to the first system word (which it is presumed the caller requires - and in all current use cases this is so). As we currently only specify that the VMA flags bitmap size is equal to BITS_PER_LONG number of bits, this is a noop, but is defensive in preparation for a future change that increases this. We additionally update the VMA userland test declarations to implement the same changes there. Finally, we update the rust code to reference vma->vm_flags on update rather than vma->__vm_flags which has been removed. This is safe for now, albeit it is implicitly performing a const cast. Once we introduce flag helpers we can improve this more. No functional change intended. Link: https://lkml.kernel.org/r/bab179d7b153ac12f221b7d65caac2759282cfe9.1764064557.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Pedro Falcato <pfalcato@suse.de> Acked-by: Alice Ryhl <aliceryhl@google.com> [rust] Cc: Alex Gaynor <alex.gaynor@gmail.com> Cc: Alistair Popple <apopple@nvidia.com> Cc: Andreas Hindborg <a.hindborg@kernel.org> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Barry Song <baohua@kernel.org> Cc: Ben Segall <bsegall@google.com> Cc: Björn Roy Baron <bjorn3_gh@protonmail.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Byungchul Park <byungchul@sk.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Chris Li <chrisl@kernel.org> Cc: Danilo Krummrich <dakr@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Dev Jain <dev.jain@arm.com> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Gary Guo <gary@garyguo.net> Cc: Gregory Price <gourry@gourry.net> Cc: "Huang, Ying" <ying.huang@linux.alibaba.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Joshua Hahn <joshua.hahnjy@gmail.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Kairui Song <kasong@tencent.com> Cc: Kees Cook <kees@kernel.org> Cc: Kemeng Shi <shikemeng@huaweicloud.com> Cc: Lance Yang <lance.yang@linux.dev> Cc: Leon Romanovsky <leon@kernel.org> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mathew Brost <matthew.brost@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mel Gorman <mgorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Nico Pache <npache@redhat.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Rakie Kim <rakie.kim@sk.com> Cc: Rik van Riel <riel@surriel.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Trevor Gross <tmgross@umich.edu> Cc: Valentin Schneider <vschneid@redhat.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Wei Xu <weixugc@google.com> Cc: xu xin <xu.xin16@zte.com.cn> Cc: Yuanchu Xie <yuanchu@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-25 10:01:02 +00:00
tools/testing/vma: separate out vma_internal.h into logical headers The vma_internal.h file is becoming entirely unmanageable. It combines duplicated kernel implementation logic that needs to be kept in-sync with the kernel, stubbed out declarations that we simply ignore for testing purposes and custom logic added to aid testing. If we separate each of the three things into separate headers it makes things far more manageable, so do so: * include/stubs.h contains the stubbed declarations, * include/dup.h contains the duplicated kernel declarations, and * include/custom.h contains declarations customised for testing. [lorenzo.stoakes@oracle.com: avoid a duplicate struct define] Link: https://lkml.kernel.org/r/1e032732-61c3-485c-9aa7-6a09016fefc1@lucifer.local Link: https://lkml.kernel.org/r/dd57baf5b5986cb96a167150ac712cbe804b63ee.1769097829.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Cc: Damien Le Moal <dlemoal@kernel.org> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Yury Norov <ynorov@nvidia.com> Cc: Chris Mason <clm@fb.com> Cc: Pedro Falcato <pfalcato@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-22 16:06:21 +00:00
mm: introduce vma_flags_count() and vma[_flags]_test_single_mask() vma_flags_count() determines how many bits are set in VMA flags, using bitmap_weight(). vma_flags_test_single_mask() determines if a vma_flags_t set of flags contains a single flag specified as another vma_flags_t value, or if the sought flag mask is empty, it is defined to return false. This is useful when we want to declare a VMA flag as optionally a single flag in a mask or empty depending on kernel configuration. This allows us to have VM_NONE-like semantics when checking whether the flag is set. In a subsequent patch, we introduce the use of VMA_DROPPABLE of type vma_flags_t using precisely these semantics. It would be actively confusing to use vma_flags_test_any_single_mask() for this (and vma_flags_test_all_mask() is not correct to use here, as it trivially returns true when tested against an empty vma flags mask). We introduce vma_flags_count() to be able to assert that the compared flag mask is singular or empty, checked when CONFIG_DEBUG_VM is enabled. Also update the VMA tests as part of this change. Link: https://lkml.kernel.org/r/cd778dd02b9f2a01eb54d25a49dea8ec2ddf7753.1774034900.git.ljs@kernel.org Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org> Acked-by: Vlastimil Babka (SUSE) <vbabka@kernel.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: "Borislav Petkov (AMD)" <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Dinh Nguyen <dinguyen@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Kees Cook <kees@kernel.org> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Ondrej Mosnacek <omosnace@redhat.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Moore <paul@paul-moore.com> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Richard Weinberger <richard@nod.at> Cc: Russell King <linux@armlinux.org.uk> Cc: Stephen Smalley <stephen.smalley.work@gmail.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vineet Gupta <vgupta@kernel.org> Cc: WANG Xuerui <kernel@xen0n.name> Cc: Will Deacon <will@kernel.org> Cc: xu xin <xu.xin16@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-03-20 19:38:32 +00:00
tools/testing/vma: separate out vma_internal.h into logical headers The vma_internal.h file is becoming entirely unmanageable. It combines duplicated kernel implementation logic that needs to be kept in-sync with the kernel, stubbed out declarations that we simply ignore for testing purposes and custom logic added to aid testing. If we separate each of the three things into separate headers it makes things far more manageable, so do so: * include/stubs.h contains the stubbed declarations, * include/dup.h contains the duplicated kernel declarations, and * include/custom.h contains declarations customised for testing. [lorenzo.stoakes@oracle.com: avoid a duplicate struct define] Link: https://lkml.kernel.org/r/1e032732-61c3-485c-9aa7-6a09016fefc1@lucifer.local Link: https://lkml.kernel.org/r/dd57baf5b5986cb96a167150ac712cbe804b63ee.1769097829.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Zi Yan <ziy@nvidia.com> Cc: Damien Le Moal <dlemoal@kernel.org> Cc: "Darrick J. Wong" <djwong@kernel.org> Cc: Jarkko Sakkinen <jarkko@kernel.org> Cc: Yury Norov <ynorov@nvidia.com> Cc: Chris Mason <clm@fb.com> Cc: Pedro Falcato <pfalcato@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-22 16:06:21 +00:00
mm: add ability to take further action in vm_area_desc Some drivers/filesystems need to perform additional tasks after the VMA is set up. This is typically in the form of pre-population. The forms of pre-population most likely to be performed are a PFN remap or the insertion of normal folios and PFNs into a mixed map. We start by implementing the PFN remap functionality, ensuring that we perform the appropriate actions at the appropriate time - that is setting flags at the point of .mmap_prepare, and performing the actual remap at the point at which the VMA is fully established. This prevents the driver from doing anything too crazy with a VMA at any stage, and we retain complete control over how the mm functionality is applied. Unfortunately callers still do often require some kind of custom action, so we add an optional success/error _hook to allow the caller to do something after the action has succeeded or failed. This is done at the point when the VMA has already been established, so the harm that can be done is limited. The error hook can be used to filter errors if necessary. There may be cases in which the caller absolutely must hold the file rmap lock until the operation is entirely complete. It is an edge case, but certainly the hugetlbfs mmap hook requires it. To accommodate this, we add the hide_from_rmap_until_complete flag to the mmap_action type. In this case, if a new VMA is allocated, we will hold the file rmap lock until the operation is entirely completed (including any success/error hooks). Note that we do not need to update __compat_vma_mmap() to accommodate this flag, as this function will be invoked from an .mmap handler whose VMA is not yet visible, so we implicitly hide it from the rmap. If any error arises on these final actions, we simply unmap the VMA altogether. Also update the stacked filesystem compatibility layer to utilise the action behaviour, and update the VMA tests accordingly. While we're here, rename __compat_vma_mmap_prepare() to __compat_vma_mmap() as we are now performing actions invoked by the mmap_prepare in addition to just the mmap_prepare hook. Link: https://lkml.kernel.org/r/2601199a7b2eaeadfcd8ab6e199c6d1706650c94.1760959442.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andreas Larsson <andreas@gaisler.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Baoquan He <bhe@redhat.com> Cc: Chatre, Reinette <reinette.chatre@intel.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hugh Dickins <hughd@google.com> Cc: James Morse <james.morse@arm.com> Cc: Jan Kara <jack@suse.cz> Cc: Jann Horn <jannh@google.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Nicolas Pitre <nico@fluxnic.net> Cc: Oscar Salvador <osalvador@suse.de> Cc: Pedro Falcato <pfalcato@suse.de> Cc: Robin Murohy <robin.murphy@arm.com> Cc: Sumanth Korikkar <sumanthk@linux.ibm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: "Uladzislau Rezki (Sony)" <urezki@gmail.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-10-20 13:11:27 +01:00
tools: add skeleton code for userland testing of VMA logic Establish a new userland VMA unit testing implementation under tools/testing which utilises existing logic providing maple tree support in userland utilising the now-shared code previously exclusive to radix tree testing. This provides fundamental VMA operations whose API is defined in mm/vma.h, while stubbing out superfluous functionality. This exists as a proof-of-concept, with the test implementation functional and sufficient to allow userland compilation of vma.c, but containing only cursory tests to demonstrate basic functionality. Link: https://lkml.kernel.org/r/533ffa2eec771cbe6b387dd049a7f128a53eb616.1722251717.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Tested-by: SeongJae Park <sj@kernel.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Brendan Higgins <brendanhiggins@google.com> Cc: Christian Brauner <brauner@kernel.org> Cc: David Gow <davidgow@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Jan Kara <jack@suse.cz> Cc: Kees Cook <kees@kernel.org> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Rae Moar <rmoar@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Pengfei Xu <pengfei.xu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-29 12:50:41 +01:00