From: Christoph Hellwig <hch@xxxxxx> Subject: mm: use untagged_addr() for get_user_pages_fast addresses Patch series "switch the remaining architectures to use generic GUP", v4. A series to switch mips, sh and sparc64 to use the generic GUP code so that we only have one codebase to touch for further improvements to this code. This patch (of 16): This will allow sparc64, or any future architecture with memory tagging to override its tags for get_user_pages and get_user_pages_fast. Link: http://lkml.kernel.org/r/20190625143715.1689-2-hch@xxxxxx Signed-off-by: Christoph Hellwig <hch@xxxxxx> Reviewed-by: Khalid Aziz <khalid.aziz@xxxxxxxxxx> Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx> Cc: Paul Burton <paul.burton@xxxxxxxx> Cc: James Hogan <jhogan@xxxxxxxxxx> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx> Cc: Rich Felker <dalias@xxxxxxxx> Cc: David Miller <davem@xxxxxxxxxxxxx> Cc: Nicholas Piggin <npiggin@xxxxxxxxx> Cc: Khalid Aziz <khalid.aziz@xxxxxxxxxx> Cc: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/gup.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/mm/gup.c~mm-use-untagged_addr-for-get_user_pages_fast-addresses +++ a/mm/gup.c @@ -2146,7 +2146,7 @@ int __get_user_pages_fast(unsigned long unsigned long flags; int nr = 0; - start &= PAGE_MASK; + start = untagged_addr(start) & PAGE_MASK; len = (unsigned long) nr_pages << PAGE_SHIFT; end = start + len; @@ -2219,7 +2219,7 @@ int get_user_pages_fast(unsigned long st unsigned long addr, len, end; int nr = 0, ret = 0; - start &= PAGE_MASK; + start = untagged_addr(start) & PAGE_MASK; addr = start; len = (unsigned long) nr_pages << PAGE_SHIFT; end = start + len; _
