mm: treewide: remove unused address argument from pte_alloc functions

Patch series "Add support for fast mremap".

This series speeds up the mremap(2) syscall by copying page tables at
the PMD level even for non-THP systems.  There is concern that the extra
'address' argument that mremap passes to pte_alloc may do something
subtle architecture related in the future that may make the scheme not
work.  Also we find that there is no point in passing the 'address' to
pte_alloc since its unused.  This patch therefore removes this argument
tree-wide resulting in a nice negative diff as well.  Also ensuring
along the way that the enabled architectures do not do anything funky
with the 'address' argument that goes unnoticed by the optimization.

Build and boot tested on x86-64.  Build tested on arm64.  The config
enablement patch for arm64 will be posted in the future after more
testing.

The changes were obtained by applying the following Coccinelle script.
(thanks Julia for answering all Coccinelle questions!).
Following fix ups were done manually:
* Removal of address argument from  pte_fragment_alloc
* Removal of pte_alloc_one_fast definitions from m68k and microblaze.

// Options: --include-headers --no-includes
// Note: I split the 'identifier fn' line, so if you are manually
// running it, please unsplit it so it runs for you.

virtual patch

@pte_alloc_func_def depends on patch exists@
identifier E2;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
type T2;
@@

 fn(...
- , T2 E2
 )
 { ... }

@pte_alloc_func_proto_noarg depends on patch exists@
type T1, T2, T3, T4;
identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@

(
- T3 fn(T1, T2);
+ T3 fn(T1);
|
- T3 fn(T1, T2, T4);
+ T3 fn(T1, T2);
)

@pte_alloc_func_proto depends on patch exists@
identifier E1, E2, E4;
type T1, T2, T3, T4;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@

(
- T3 fn(T1 E1, T2 E2);
+ T3 fn(T1 E1);
|
- T3 fn(T1 E1, T2 E2, T4 E4);
+ T3 fn(T1 E1, T2 E2);
)

@pte_alloc_func_call depends on patch exists@
expression E2;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@

 fn(...
-,  E2
 )

@pte_alloc_macro depends on patch exists@
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
identifier a, b, c;
expression e;
position p;
@@

(
- #define fn(a, b, c) e
+ #define fn(a, b) e
|
- #define fn(a, b) e
+ #define fn(a) e
)

Link: http://lkml.kernel.org/r/20181108181201.88826-2-joelaf@google.com
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Suggested-by: Kirill A. Shutemov <kirill@shutemov.name>
Acked-by: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 3 insertions, 19 deletions

diff --git a/arch/microblaze/include/asm/pgalloc.h b/arch/microblaze/include/asm/pgalloc.h
index 7c89390c0c13..f4cc9ffc449e 100644
--- a/arch/microblaze/include/asm/pgalloc.h
+++ b/arch/microblaze/include/asm/pgalloc.h
@@ -108,10 +108,9 @@ static inline void free_pgd_slow(pgd_t *pgd)
 #define pmd_alloc_one_fast(mm, address)	({ BUG(); ((pmd_t *)1); })
 #define pmd_alloc_one(mm, address)	({ BUG(); ((pmd_t *)2); })
 
-extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr);
+extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm);
 
-static inline struct page *pte_alloc_one(struct mm_struct *mm,
-		unsigned long address)
+static inline struct page *pte_alloc_one(struct mm_struct *mm)
 {
 	struct page *ptepage;
 
@@ -132,20 +131,6 @@ static inline struct page *pte_alloc_one(struct mm_struct *mm,
 	return ptepage;
 }
 
-static inline pte_t *pte_alloc_one_fast(struct mm_struct *mm,
-		unsigned long address)
-{
-	unsigned long *ret;
-
-	ret = pte_quicklist;
-	if (ret != NULL) {
-		pte_quicklist = (unsigned long *)(*ret);
-		ret[0] = 0;
-		pgtable_cache_size--;
-	}
-	return (pte_t *)ret;
-}
-
 static inline void pte_free_fast(pte_t *pte)
 {
 	*(unsigned long **)pte = pte_quicklist;
diff --git a/arch/microblaze/mm/pgtable.c b/arch/microblaze/mm/pgtable.c
index 7f525962cdfa..c2ce1e42b888 100644
--- a/arch/microblaze/mm/pgtable.c
+++ b/arch/microblaze/mm/pgtable.c
@@ -235,8 +235,7 @@ unsigned long iopa(unsigned long addr)
 	return pa;
 }
 
-__ref pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
-		unsigned long address)
+__ref pte_t *pte_alloc_one_kernel(struct mm_struct *mm)
 {
 	pte_t *pte;
 	if (mem_init_done) {