x86/mm/gup: Switch GUP to the generic get_user_page_fast() implementation

This patch provides all required callbacks required by the generic
get_user_pages_fast() code and switches x86 over - and removes
the platform specific implementation.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170606113133.22974-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 5 insertions, 5 deletions

diff --git a/mm/gup.c b/mm/gup.c
index b3c7214d710d..2050f9fe121d 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1151,7 +1151,7 @@ struct page *get_dump_page(unsigned long addr)
 #endif /* CONFIG_ELF_CORE */
 
 /*
- * Generic RCU Fast GUP
+ * Generic Fast GUP
  *
  * get_user_pages_fast attempts to pin user pages by walking the page
  * tables directly and avoids taking locks. Thus the walker needs to be
@@ -1172,8 +1172,8 @@ struct page *get_dump_page(unsigned long addr)
  * Before activating this code, please be aware that the following assumptions
  * are currently made:
  *
- *  *) HAVE_RCU_TABLE_FREE is enabled, and tlb_remove_table is used to free
- *      pages containing page tables.
+ *  *) Either HAVE_RCU_TABLE_FREE is enabled, and tlb_remove_table() is used to
+ *  free pages containing page tables or TLB flushing requires IPI broadcast.
  *
  *  *) ptes can be read atomically by the architecture.
  *
@@ -1183,7 +1183,7 @@ struct page *get_dump_page(unsigned long addr)
  *
  * This code is based heavily on the PowerPC implementation by Nick Piggin.
  */
-#ifdef CONFIG_HAVE_GENERIC_RCU_GUP
+#ifdef CONFIG_HAVE_GENERIC_GUP
 
 #ifndef gup_get_pte
 /*
@@ -1673,4 +1673,4 @@ int get_user_pages_fast(unsigned long start, int nr_pages, int write,
         return ret;
 }
 
-#endif /* CONFIG_HAVE_GENERIC_RCU_GUP */
+#endif /* CONFIG_HAVE_GENERIC_GUP */