diff options
author | Christoph Hellwig <hch@lst.de> | 2019-07-12 06:57:21 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-07-12 21:05:45 +0300 |
commit | 050a9adc64383aed3429a31432b4f5a7b0cdc8ac (patch) | |
tree | e8bf6fec0f1a4fd0aadbbad9f9834cb648ff1129 /mm/util.c | |
parent | d3649f68b4336e7ef7aa264cf05ba1265feb0968 (diff) | |
download | linux-050a9adc64383aed3429a31432b4f5a7b0cdc8ac.tar.xz |
mm: consolidate the get_user_pages* implementations
Always build mm/gup.c so that we don't have to provide separate nommu
stubs. Also merge the get_user_pages_fast and __get_user_pages_fast stubs
when HAVE_FAST_GUP into the main implementations, which will never call
the fast path if HAVE_FAST_GUP is not set.
This also ensures the new put_user_pages* helpers are available for nommu,
as those are currently missing, which would create a problem as soon as we
actually grew users for it.
Link: http://lkml.kernel.org/r/20190625143715.1689-13-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Miller <davem@davemloft.net>
Cc: James Hogan <jhogan@kernel.org>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/util.c')
-rw-r--r-- | mm/util.c | 47 |
1 files changed, 0 insertions, 47 deletions
diff --git a/mm/util.c b/mm/util.c index 9834c4ab7d8e..68575a315dc5 100644 --- a/mm/util.c +++ b/mm/util.c @@ -300,53 +300,6 @@ void arch_pick_mmap_layout(struct mm_struct *mm, struct rlimit *rlim_stack) } #endif -/* - * Like get_user_pages_fast() except its IRQ-safe in that it won't fall - * back to the regular GUP. - * Note a difference with get_user_pages_fast: this always returns the - * number of pages pinned, 0 if no pages were pinned. - * If the architecture does not support this function, simply return with no - * pages pinned. - */ -int __weak __get_user_pages_fast(unsigned long start, - int nr_pages, int write, struct page **pages) -{ - return 0; -} -EXPORT_SYMBOL_GPL(__get_user_pages_fast); - -/** - * get_user_pages_fast() - pin user pages in memory - * @start: starting user address - * @nr_pages: number of pages from start to pin - * @gup_flags: flags modifying pin behaviour - * @pages: array that receives pointers to the pages pinned. - * Should be at least nr_pages long. - * - * get_user_pages_fast provides equivalent functionality to get_user_pages, - * operating on current and current->mm, with force=0 and vma=NULL. However - * unlike get_user_pages, it must be called without mmap_sem held. - * - * get_user_pages_fast may take mmap_sem and page table locks, so no - * assumptions can be made about lack of locking. get_user_pages_fast is to be - * implemented in a way that is advantageous (vs get_user_pages()) when the - * user memory area is already faulted in and present in ptes. However if the - * pages have to be faulted in, it may turn out to be slightly slower so - * callers need to carefully consider what to use. On many architectures, - * get_user_pages_fast simply falls back to get_user_pages. - * - * Return: number of pages pinned. This may be fewer than the number - * requested. If nr_pages is 0 or negative, returns 0. If no pages - * were pinned, returns -errno. - */ -int __weak get_user_pages_fast(unsigned long start, - int nr_pages, unsigned int gup_flags, - struct page **pages) -{ - return get_user_pages_unlocked(start, nr_pages, pages, gup_flags); -} -EXPORT_SYMBOL_GPL(get_user_pages_fast); - unsigned long vm_mmap_pgoff(struct file *file, unsigned long addr, unsigned long len, unsigned long prot, unsigned long flag, unsigned long pgoff) |