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authorLinus Torvalds <torvalds@linux-foundation.org>2023-08-29 14:25:26 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2023-08-29 14:25:26 -0700
commitb96a3e9142fdf346b05b20e867b4f0dfca119e96 (patch)
treeb338a8f8930abc24888fc3871c6627f6ad46e23b /Documentation/core-api
parent651a00bc56403161351090a9d7ddbd7095975324 (diff)
parent52ae298e3e5c9be5bb95e1c6d9199e5210f2a156 (diff)
Merge tag 'mm-stable-2023-08-28-18-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton: - Some swap cleanups from Ma Wupeng ("fix WARN_ON in add_to_avail_list") - Peter Xu has a series (mm/gup: Unify hugetlb, speed up thp") which reduces the special-case code for handling hugetlb pages in GUP. It also speeds up GUP handling of transparent hugepages. - Peng Zhang provides some maple tree speedups ("Optimize the fast path of mas_store()"). - Sergey Senozhatsky has improved te performance of zsmalloc during compaction (zsmalloc: small compaction improvements"). - Domenico Cerasuolo has developed additional selftest code for zswap ("selftests: cgroup: add zswap test program"). - xu xin has doe some work on KSM's handling of zero pages. These changes are mainly to enable the user to better understand the effectiveness of KSM's treatment of zero pages ("ksm: support tracking KSM-placed zero-pages"). - Jeff Xu has fixes the behaviour of memfd's MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED sysctl ("mm/memfd: fix sysctl MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED"). - David Howells has fixed an fscache optimization ("mm, netfs, fscache: Stop read optimisation when folio removed from pagecache"). - Axel Rasmussen has given userfaultfd the ability to simulate memory poisoning ("add UFFDIO_POISON to simulate memory poisoning with UFFD"). - Miaohe Lin has contributed some routine maintenance work on the memory-failure code ("mm: memory-failure: remove unneeded PageHuge() check"). - Peng Zhang has contributed some maintenance work on the maple tree code ("Improve the validation for maple tree and some cleanup"). - Hugh Dickins has optimized the collapsing of shmem or file pages into THPs ("mm: free retracted page table by RCU"). - Jiaqi Yan has a patch series which permits us to use the healthy subpages within a hardware poisoned huge page for general purposes ("Improve hugetlbfs read on HWPOISON hugepages"). - Kemeng Shi has done some maintenance work on the pagetable-check code ("Remove unused parameters in page_table_check"). - More folioification work from Matthew Wilcox ("More filesystem folio conversions for 6.6"), ("Followup folio conversions for zswap"). And from ZhangPeng ("Convert several functions in page_io.c to use a folio"). - page_ext cleanups from Kemeng Shi ("minor cleanups for page_ext"). - Baoquan He has converted some architectures to use the GENERIC_IOREMAP ioremap()/iounmap() code ("mm: ioremap: Convert architectures to take GENERIC_IOREMAP way"). - Anshuman Khandual has optimized arm64 tlb shootdown ("arm64: support batched/deferred tlb shootdown during page reclamation/migration"). - Better maple tree lockdep checking from Liam Howlett ("More strict maple tree lockdep"). Liam also developed some efficiency improvements ("Reduce preallocations for maple tree"). - Cleanup and optimization to the secondary IOMMU TLB invalidation, from Alistair Popple ("Invalidate secondary IOMMU TLB on permission upgrade"). - Ryan Roberts fixes some arm64 MM selftest issues ("selftests/mm fixes for arm64"). - Kemeng Shi provides some maintenance work on the compaction code ("Two minor cleanups for compaction"). - Some reduction in mmap_lock pressure from Matthew Wilcox ("Handle most file-backed faults under the VMA lock"). - Aneesh Kumar contributes code to use the vmemmap optimization for DAX on ppc64, under some circumstances ("Add support for DAX vmemmap optimization for ppc64"). - page-ext cleanups from Kemeng Shi ("add page_ext_data to get client data in page_ext"), ("minor cleanups to page_ext header"). - Some zswap cleanups from Johannes Weiner ("mm: zswap: three cleanups"). - kmsan cleanups from ZhangPeng ("minor cleanups for kmsan"). - VMA handling cleanups from Kefeng Wang ("mm: convert to vma_is_initial_heap/stack()"). - DAMON feature work from SeongJae Park ("mm/damon/sysfs-schemes: implement DAMOS tried total bytes file"), ("Extend DAMOS filters for address ranges and DAMON monitoring targets"). - Compaction work from Kemeng Shi ("Fixes and cleanups to compaction"). - Liam Howlett has improved the maple tree node replacement code ("maple_tree: Change replacement strategy"). - ZhangPeng has a general code cleanup - use the K() macro more widely ("cleanup with helper macro K()"). - Aneesh Kumar brings memmap-on-memory to ppc64 ("Add support for memmap on memory feature on ppc64"). - pagealloc cleanups from Kemeng Shi ("Two minor cleanups for pcp list in page_alloc"), ("Two minor cleanups for get pageblock migratetype"). - Vishal Moola introduces a memory descriptor for page table tracking, "struct ptdesc" ("Split ptdesc from struct page"). - memfd selftest maintenance work from Aleksa Sarai ("memfd: cleanups for vm.memfd_noexec"). - MM include file rationalization from Hugh Dickins ("arch: include asm/cacheflush.h in asm/hugetlb.h"). - THP debug output fixes from Hugh Dickins ("mm,thp: fix sloppy text output"). - kmemleak improvements from Xiaolei Wang ("mm/kmemleak: use object_cache instead of kmemleak_initialized"). - More folio-related cleanups from Matthew Wilcox ("Remove _folio_dtor and _folio_order"). - A VMA locking scalability improvement from Suren Baghdasaryan ("Per-VMA lock support for swap and userfaults"). - pagetable handling cleanups from Matthew Wilcox ("New page table range API"). - A batch of swap/thp cleanups from David Hildenbrand ("mm/swap: stop using page->private on tail pages for THP_SWAP + cleanups"). - Cleanups and speedups to the hugetlb fault handling from Matthew Wilcox ("Change calling convention for ->huge_fault"). - Matthew Wilcox has also done some maintenance work on the MM subsystem documentation ("Improve mm documentation"). * tag 'mm-stable-2023-08-28-18-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (489 commits) maple_tree: shrink struct maple_tree maple_tree: clean up mas_wr_append() secretmem: convert page_is_secretmem() to folio_is_secretmem() nios2: fix flush_dcache_page() for usage from irq context hugetlb: add documentation for vma_kernel_pagesize() mm: add orphaned kernel-doc to the rst files. mm: fix clean_record_shared_mapping_range kernel-doc mm: fix get_mctgt_type() kernel-doc mm: fix kernel-doc warning from tlb_flush_rmaps() mm: remove enum page_entry_size mm: allow ->huge_fault() to be called without the mmap_lock held mm: move PMD_ORDER to pgtable.h mm: remove checks for pte_index memcg: remove duplication detection for mem_cgroup_uncharge_swap mm/huge_memory: work on folio->swap instead of page->private when splitting folio mm/swap: inline folio_set_swap_entry() and folio_swap_entry() mm/swap: use dedicated entry for swap in folio mm/swap: stop using page->private on tail pages for THP_SWAP selftests/mm: fix WARNING comparing pointer to 0 selftests: cgroup: fix test_kmem_memcg_deletion kernel mem check ...
Diffstat (limited to 'Documentation/core-api')
-rw-r--r--Documentation/core-api/cachetlb.rst55
-rw-r--r--Documentation/core-api/mm-api.rst25
2 files changed, 52 insertions, 28 deletions
diff --git a/Documentation/core-api/cachetlb.rst b/Documentation/core-api/cachetlb.rst
index 5c0552e78c58..889fc84ccd1b 100644
--- a/Documentation/core-api/cachetlb.rst
+++ b/Documentation/core-api/cachetlb.rst
@@ -88,13 +88,17 @@ changes occur:
This is used primarily during fault processing.
-5) ``void update_mmu_cache(struct vm_area_struct *vma,
- unsigned long address, pte_t *ptep)``
+5) ``void update_mmu_cache_range(struct vm_fault *vmf,
+ struct vm_area_struct *vma, unsigned long address, pte_t *ptep,
+ unsigned int nr)``
- At the end of every page fault, this routine is invoked to
- tell the architecture specific code that a translation
- now exists at virtual address "address" for address space
- "vma->vm_mm", in the software page tables.
+ At the end of every page fault, this routine is invoked to tell
+ the architecture specific code that translations now exists
+ in the software page tables for address space "vma->vm_mm"
+ at virtual address "address" for "nr" consecutive pages.
+
+ This routine is also invoked in various other places which pass
+ a NULL "vmf".
A port may use this information in any way it so chooses.
For example, it could use this event to pre-load TLB
@@ -269,7 +273,7 @@ maps this page at its virtual address.
If D-cache aliasing is not an issue, these two routines may
simply call memcpy/memset directly and do nothing more.
- ``void flush_dcache_page(struct page *page)``
+ ``void flush_dcache_folio(struct folio *folio)``
This routines must be called when:
@@ -277,7 +281,7 @@ maps this page at its virtual address.
and / or in high memory
b) the kernel is about to read from a page cache page and user space
shared/writable mappings of this page potentially exist. Note
- that {get,pin}_user_pages{_fast} already call flush_dcache_page
+ that {get,pin}_user_pages{_fast} already call flush_dcache_folio
on any page found in the user address space and thus driver
code rarely needs to take this into account.
@@ -291,7 +295,7 @@ maps this page at its virtual address.
The phrase "kernel writes to a page cache page" means, specifically,
that the kernel executes store instructions that dirty data in that
- page at the page->virtual mapping of that page. It is important to
+ page at the kernel virtual mapping of that page. It is important to
flush here to handle D-cache aliasing, to make sure these kernel stores
are visible to user space mappings of that page.
@@ -302,21 +306,22 @@ maps this page at its virtual address.
If D-cache aliasing is not an issue, this routine may simply be defined
as a nop on that architecture.
- There is a bit set aside in page->flags (PG_arch_1) as "architecture
+ There is a bit set aside in folio->flags (PG_arch_1) as "architecture
private". The kernel guarantees that, for pagecache pages, it will
clear this bit when such a page first enters the pagecache.
- This allows these interfaces to be implemented much more efficiently.
- It allows one to "defer" (perhaps indefinitely) the actual flush if
- there are currently no user processes mapping this page. See sparc64's
- flush_dcache_page and update_mmu_cache implementations for an example
- of how to go about doing this.
+ This allows these interfaces to be implemented much more
+ efficiently. It allows one to "defer" (perhaps indefinitely) the
+ actual flush if there are currently no user processes mapping this
+ page. See sparc64's flush_dcache_folio and update_mmu_cache_range
+ implementations for an example of how to go about doing this.
- The idea is, first at flush_dcache_page() time, if page_file_mapping()
- returns a mapping, and mapping_mapped on that mapping returns %false,
- just mark the architecture private page flag bit. Later, in
- update_mmu_cache(), a check is made of this flag bit, and if set the
- flush is done and the flag bit is cleared.
+ The idea is, first at flush_dcache_folio() time, if
+ folio_flush_mapping() returns a mapping, and mapping_mapped() on that
+ mapping returns %false, just mark the architecture private page
+ flag bit. Later, in update_mmu_cache_range(), a check is made
+ of this flag bit, and if set the flush is done and the flag bit
+ is cleared.
.. important::
@@ -326,12 +331,6 @@ maps this page at its virtual address.
dirty. Again, see sparc64 for examples of how
to deal with this.
- ``void flush_dcache_folio(struct folio *folio)``
- This function is called under the same circumstances as
- flush_dcache_page(). It allows the architecture to
- optimise for flushing the entire folio of pages instead
- of flushing one page at a time.
-
``void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
unsigned long user_vaddr, void *dst, void *src, int len)``
``void copy_from_user_page(struct vm_area_struct *vma, struct page *page,
@@ -352,7 +351,7 @@ maps this page at its virtual address.
When the kernel needs to access the contents of an anonymous
page, it calls this function (currently only
- get_user_pages()). Note: flush_dcache_page() deliberately
+ get_user_pages()). Note: flush_dcache_folio() deliberately
doesn't work for an anonymous page. The default
implementation is a nop (and should remain so for all coherent
architectures). For incoherent architectures, it should flush
@@ -369,7 +368,7 @@ maps this page at its virtual address.
``void flush_icache_page(struct vm_area_struct *vma, struct page *page)``
All the functionality of flush_icache_page can be implemented in
- flush_dcache_page and update_mmu_cache. In the future, the hope
+ flush_dcache_folio and update_mmu_cache_range. In the future, the hope
is to remove this interface completely.
The final category of APIs is for I/O to deliberately aliased address
diff --git a/Documentation/core-api/mm-api.rst b/Documentation/core-api/mm-api.rst
index f5dde5bceaea..2d091c873d1e 100644
--- a/Documentation/core-api/mm-api.rst
+++ b/Documentation/core-api/mm-api.rst
@@ -115,3 +115,28 @@ More Memory Management Functions
.. kernel-doc:: include/linux/mmzone.h
.. kernel-doc:: mm/util.c
:functions: folio_mapping
+
+.. kernel-doc:: mm/rmap.c
+.. kernel-doc:: mm/migrate.c
+.. kernel-doc:: mm/mmap.c
+.. kernel-doc:: mm/kmemleak.c
+.. #kernel-doc:: mm/hmm.c (build warnings)
+.. kernel-doc:: mm/memremap.c
+.. kernel-doc:: mm/hugetlb.c
+.. kernel-doc:: mm/swap.c
+.. kernel-doc:: mm/zpool.c
+.. kernel-doc:: mm/memcontrol.c
+.. #kernel-doc:: mm/memory-tiers.c (build warnings)
+.. kernel-doc:: mm/shmem.c
+.. kernel-doc:: mm/migrate_device.c
+.. #kernel-doc:: mm/nommu.c (duplicates kernel-doc from other files)
+.. kernel-doc:: mm/mapping_dirty_helpers.c
+.. #kernel-doc:: mm/memory-failure.c (build warnings)
+.. kernel-doc:: mm/percpu.c
+.. kernel-doc:: mm/maccess.c
+.. kernel-doc:: mm/vmscan.c
+.. kernel-doc:: mm/memory_hotplug.c
+.. kernel-doc:: mm/mmu_notifier.c
+.. kernel-doc:: mm/balloon_compaction.c
+.. kernel-doc:: mm/huge_memory.c
+.. kernel-doc:: mm/io-mapping.c