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author | Matthew Wilcox (Oracle) <willy@infradead.org> | 2023-08-02 18:13:31 +0300 |
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committer | Andrew Morton <akpm@linux-foundation.org> | 2023-08-25 02:20:18 +0300 |
commit | 3a255267f6dff40e193501cf731f409ce9175503 (patch) | |
tree | 32ec68eb3d188902b2571145419b9fbab79d330c /Documentation | |
parent | a379322022c0961fe0b638cdd842d3c38eeff92c (diff) | |
download | linux-3a255267f6dff40e193501cf731f409ce9175503.tar.xz |
mm: add generic flush_icache_pages() and documentation
flush_icache_page() is deprecated but not yet removed, so add a range
version of it. Change the documentation to refer to
update_mmu_cache_range() instead of update_mmu_cache().
Link: https://lkml.kernel.org/r/20230802151406.3735276-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/core-api/cachetlb.rst | 39 |
1 files changed, 22 insertions, 17 deletions
diff --git a/Documentation/core-api/cachetlb.rst b/Documentation/core-api/cachetlb.rst index 5c0552e78c58..b645947954fb 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 @@ -306,17 +310,18 @@ maps this page at its virtual address. 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_page 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_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_range(), a check is made + of this flag bit, and if set the flush is done and the flag bit + is cleared. .. important:: @@ -369,7 +374,7 @@ 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_page 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 |