kernel/linux.git/arch/mips/mm/cache.c, branch linux-5.9.y

arch/kunmap_atomic: consolidate duplicate code

2020-06-05T02:06:22+00:00

Every single architecture (including !CONFIG_HIGHMEM) calls... pagefault_enable(); preempt_enable(); ... before returning from __kunmap_atomic(). Lift this code into the kunmap_atomic() macro. While we are at it rename __kunmap_atomic() to kunmap_atomic_high() to be consistent. [ira.weiny@intel.com: don't enable pagefault/preempt twice] Link: http://lkml.kernel.org/r/20200518184843.3029640-1-ira.weiny@intel.com [akpm@linux-foundation.org: coding style fixes] Signed-off-by: Ira Weiny Signed-off-by: Andrew Morton Reviewed-by: Christoph Hellwig Cc: Al Viro Cc: Andy Lutomirski Cc: Benjamin Herrenschmidt Cc: Borislav Petkov Cc: Christian König Cc: Chris Zankel Cc: Daniel Vetter Cc: Dan Williams Cc: Dave Hansen Cc: "David S. Miller" Cc: Helge Deller Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: "James E.J. Bottomley" Cc: Max Filippov Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Guenter Roeck Link: http://lkml.kernel.org/r/20200507150004.1423069-8-ira.weiny@intel.com Signed-off-by: Linus Torvalds

arch/kmap_atomic: consolidate duplicate code

2020-06-05T02:06:22+00:00

Every arch has the same code to ensure atomic operations and a check for !HIGHMEM page. Remove the duplicate code by defining a core kmap_atomic() which only calls the arch specific kmap_atomic_high() when the page is high memory. [akpm@linux-foundation.org: coding style fixes] Signed-off-by: Ira Weiny Signed-off-by: Andrew Morton Reviewed-by: Christoph Hellwig Cc: Al Viro Cc: Andy Lutomirski Cc: Benjamin Herrenschmidt Cc: Borislav Petkov Cc: Christian König Cc: Chris Zankel Cc: Daniel Vetter Cc: Dan Williams Cc: Dave Hansen Cc: "David S. Miller" Cc: Helge Deller Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: "James E.J. Bottomley" Cc: Max Filippov Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20200507150004.1423069-7-ira.weiny@intel.com Signed-off-by: Linus Torvalds

MIPS: unexport __flush_icache_user_range

2020-05-11T15:59:47+00:00

__flush_icache_user_range is not used in modular code, so unexport it. Signed-off-by: Christoph Hellwig Signed-off-by: Thomas Bogendoerfer

MIPS: remove the _dma_cache_wback_inv export

2019-06-03T14:00:08+00:00

This export is not used in modular code, which is a good thing as everyone should use the proper DMA API instead. Signed-off-by: Christoph Hellwig Acked-by: Paul Burton

MIPS: Delete unused flush_cache_sigtramp()

2019-02-07T20:59:45+00:00

Commit adcc81f148d7 ("MIPS: math-emu: Write-protect delay slot emulation pages") left flush_cache_sigtramp() unused. Delete the dead code. Signed-off-by: Paul Burton Cc: Davidlohr Bueso Cc: linux-mips@vger.kernel.org

Remove 'type' argument from access_ok() function

2019-01-04T02:57:57+00:00

Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument of the user address range verification function since we got rid of the old racy i386-only code to walk page tables by hand. It existed because the original 80386 would not honor the write protect bit when in kernel mode, so you had to do COW by hand before doing any user access. But we haven't supported that in a long time, and these days the 'type' argument is a purely historical artifact. A discussion about extending 'user_access_begin()' to do the range checking resulted this patch, because there is no way we're going to move the old VERIFY_xyz interface to that model. And it's best done at the end of the merge window when I've done most of my merges, so let's just get this done once and for all. This patch was mostly done with a sed-script, with manual fix-ups for the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. There were a couple of notable cases: - csky still had the old "verify_area()" name as an alias. - the iter_iov code had magical hardcoded knowledge of the actual values of VERIFY_{READ,WRITE} (not that they mattered, since nothing really used it) - microblaze used the type argument for a debug printout but other than those oddities this should be a total no-op patch. I tried to fix up all architectures, did fairly extensive grepping for access_ok() uses, and the changes are trivial, but I may have missed something. Any missed conversion should be trivially fixable, though. Signed-off-by: Linus Torvalds

MIPS: simplify CONFIG_DMA_NONCOHERENT ifdefs

2018-06-24T16:26:02+00:00

CONFIG_DMA_MAYBE_COHERENT already selects CONFIG_DMA_NONCOHERENT, so we can remove the extra conditions. Signed-off-by: Christoph Hellwig Reviewed-by: Paul Burton Patchwork: https://patchwork.linux-mips.org/patch/19529/ Signed-off-by: Paul Burton Cc: Florian Fainelli Cc: David Daney Cc: Kevin Cernekee Cc: Jiaxun Yang Cc: Tom Bogendoerfer Cc: Huacai Chen Cc: iommu@lists.linux-foundation.org Cc: linux-mips@linux-mips.org

mm: fix races between swapoff and flush dcache

2018-04-06T04:36:26+00:00

Thanks to commit 4b3ef9daa4fc ("mm/swap: split swap cache into 64MB trunks"), after swapoff the address_space associated with the swap device will be freed. So page_mapping() users which may touch the address_space need some kind of mechanism to prevent the address_space from being freed during accessing. The dcache flushing functions (flush_dcache_page(), etc) in architecture specific code may access the address_space of swap device for anonymous pages in swap cache via page_mapping() function. But in some cases there are no mechanisms to prevent the swap device from being swapoff, for example, CPU1 CPU2 __get_user_pages() swapoff() flush_dcache_page() mapping = page_mapping() ... exit_swap_address_space() ... kvfree(spaces) mapping_mapped(mapping) The address space may be accessed after being freed. But from cachetlb.txt and Russell King, flush_dcache_page() only care about file cache pages, for anonymous pages, flush_anon_page() should be used. The implementation of flush_dcache_page() in all architectures follows this too. They will check whether page_mapping() is NULL and whether mapping_mapped() is true to determine whether to flush the dcache immediately. And they will use interval tree (mapping->i_mmap) to find all user space mappings. While mapping_mapped() and mapping->i_mmap isn't used by anonymous pages in swap cache at all. So, to fix the race between swapoff and flush dcache, __page_mapping() is add to return the address_space for file cache pages and NULL otherwise. All page_mapping() invoking in flush dcache functions are replaced with page_mapping_file(). [akpm@linux-foundation.org: simplify page_mapping_file(), per Mike] Link: http://lkml.kernel.org/r/20180305083634.15174-1-ying.huang@intel.com Signed-off-by: "Huang, Ying" Reviewed-by: Andrew Morton Cc: Minchan Kim Cc: Michal Hocko Cc: Johannes Weiner Cc: Mel Gorman Cc: Dave Hansen Cc: Chen Liqin Cc: Russell King Cc: Yoshinori Sato Cc: "James E.J. Bottomley" Cc: Guan Xuetao Cc: "David S. Miller" Cc: Chris Zankel Cc: Vineet Gupta Cc: Ley Foon Tan Cc: Ralf Baechle Cc: Andi Kleen Cc: Mike Rapoport Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

MIPS: Remove __invalidate_kernel_vmap_range

2017-08-29T13:21:55+00:00

The __invalidate_kernel_vmap_range function pointer global variable isn't used anywhere. Remove it. Signed-off-by: Paul Burton Cc: linux-mips@linux-mips.org Cc: trivial@kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17174/ Signed-off-by: Ralf Baechle

MIPS: Include asm/setup.h for cpu_cache_init()

2017-08-29T13:21:54+00:00

arch/mips/mm/cache.c provides our implementation of the cpu_cache_init() function, but doesn't include the asm/setup.h header which declares it. This leads to a warning from sparse: arch/mips/mm/cache.c:274:6: warning: symbol 'cpu_cache_init' was not declared. Should it be static? Fix this by including asm/setup.h to get the declaration of cpu_cache_init(). Signed-off-by: Paul Burton Cc: linux-mips@linux-mips.org Cc: trivial@kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17168/ Signed-off-by: Ralf Baechle