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().
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>
---
Documentation/core-api/cachetlb.rst | 39 ++++++++++++++++-------------
include/asm-generic/cacheflush.h | 5 ++++
2 files changed, 27 insertions(+), 17 deletions(-)
On 7/10/23 13:43, Matthew Wilcox (Oracle) wrote:
> -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
exist
> + in the software page tables for address space "vma->vm_mm"
> + at virtual address "address" for "nr" consecutive pages.
@@ -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
@@ -78,6 +78,11 @@ static inline void flush_icache_range(unsigned long start, unsigned long end)
#endif
#ifndef flush_icache_page
+static inline void flush_icache_pages(struct vm_area_struct *vma,
+ struct page *page, unsigned int nr)
+{
+}
+
static inline void flush_icache_page(struct vm_area_struct *vma,
struct page *page)
{