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>

6 files changed, 18 insertions, 22 deletions

diff --git a/arch/powerpc/include/asm/book3s/32/pgalloc.h b/arch/powerpc/include/asm/book3s/32/pgalloc.h
index b5b955eb2fb7..3633502e102c 100644
--- a/arch/powerpc/include/asm/book3s/32/pgalloc.h
+++ b/arch/powerpc/include/asm/book3s/32/pgalloc.h
@@ -61,10 +61,10 @@ static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmdp,
 
 #define pmd_pgtable(pmd) ((pgtable_t)pmd_page_vaddr(pmd))
 
-extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr);
-extern pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long addr);
+extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm);
+extern pgtable_t pte_alloc_one(struct mm_struct *mm);
 void pte_frag_destroy(void *pte_frag);
-pte_t *pte_fragment_alloc(struct mm_struct *mm, unsigned long vmaddr, int kernel);
+pte_t *pte_fragment_alloc(struct mm_struct *mm, int kernel);
 void pte_fragment_free(unsigned long *table, int kernel);
 
 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
diff --git a/arch/powerpc/include/asm/book3s/64/pgalloc.h b/arch/powerpc/include/asm/book3s/64/pgalloc.h
index 4aba625389c4..9c1173283b96 100644
--- a/arch/powerpc/include/asm/book3s/64/pgalloc.h
+++ b/arch/powerpc/include/asm/book3s/64/pgalloc.h
@@ -39,7 +39,7 @@ extern struct vmemmap_backing *vmemmap_list;
 extern struct kmem_cache *pgtable_cache[];
 #define PGT_CACHE(shift) pgtable_cache[shift]
 
-extern pte_t *pte_fragment_alloc(struct mm_struct *, unsigned long, int);
+extern pte_t *pte_fragment_alloc(struct mm_struct *, int);
 extern pmd_t *pmd_fragment_alloc(struct mm_struct *, unsigned long);
 extern void pte_fragment_free(unsigned long *, int);
 extern void pmd_fragment_free(unsigned long *);
@@ -190,16 +190,14 @@ static inline pgtable_t pmd_pgtable(pmd_t pmd)
 	return (pgtable_t)pmd_page_vaddr(pmd);
 }
 
-static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
-					  unsigned long address)
+static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm)
 {
-	return (pte_t *)pte_fragment_alloc(mm, address, 1);
+	return (pte_t *)pte_fragment_alloc(mm, 1);
 }
 
-static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
-				      unsigned long address)
+static inline pgtable_t pte_alloc_one(struct mm_struct *mm)
 {
-	return (pgtable_t)pte_fragment_alloc(mm, address, 0);
+	return (pgtable_t)pte_fragment_alloc(mm, 0);
 }
 
 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
diff --git a/arch/powerpc/include/asm/nohash/32/pgalloc.h b/arch/powerpc/include/asm/nohash/32/pgalloc.h
index 17963951bdb0..bd186e85b4f7 100644
--- a/arch/powerpc/include/asm/nohash/32/pgalloc.h
+++ b/arch/powerpc/include/asm/nohash/32/pgalloc.h
@@ -79,10 +79,10 @@ static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmdp,
 #define pmd_pgtable(pmd) ((pgtable_t)pmd_page_vaddr(pmd))
 #endif
 
-extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr);
-extern pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long addr);
+extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm);
+extern pgtable_t pte_alloc_one(struct mm_struct *mm);
 void pte_frag_destroy(void *pte_frag);
-pte_t *pte_fragment_alloc(struct mm_struct *mm, unsigned long vmaddr, int kernel);
+pte_t *pte_fragment_alloc(struct mm_struct *mm, int kernel);
 void pte_fragment_free(unsigned long *table, int kernel);
 
 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
diff --git a/arch/powerpc/include/asm/nohash/64/pgalloc.h b/arch/powerpc/include/asm/nohash/64/pgalloc.h
index e95eb499a174..66d086f85bd5 100644
--- a/arch/powerpc/include/asm/nohash/64/pgalloc.h
+++ b/arch/powerpc/include/asm/nohash/64/pgalloc.h
@@ -93,14 +93,12 @@ static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
 }
 
 
-static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
-					  unsigned long address)
+static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm)
 {
 	return (pte_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
 }
 
-static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
-				      unsigned long address)
+static inline pgtable_t pte_alloc_one(struct mm_struct *mm)
 {
 	struct page *page;
 	pte_t *pte;
diff --git a/arch/powerpc/mm/pgtable-frag.c b/arch/powerpc/mm/pgtable-frag.c
index af23a587f019..a7b05214760c 100644
--- a/arch/powerpc/mm/pgtable-frag.c
+++ b/arch/powerpc/mm/pgtable-frag.c
@@ -95,7 +95,7 @@ static pte_t *__alloc_for_ptecache(struct mm_struct *mm, int kernel)
 	return (pte_t *)ret;
 }
 
-pte_t *pte_fragment_alloc(struct mm_struct *mm, unsigned long vmaddr, int kernel)
+pte_t *pte_fragment_alloc(struct mm_struct *mm, int kernel)
 {
 	pte_t *pte;
 
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index d67215248d82..ded71126ce4c 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -43,17 +43,17 @@ EXPORT_SYMBOL(ioremap_bot);	/* aka VMALLOC_END */
 
 extern char etext[], _stext[], _sinittext[], _einittext[];
 
-__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)
 {
 	if (!slab_is_available())
 		return memblock_alloc(PTE_FRAG_SIZE, PTE_FRAG_SIZE);
 
-	return (pte_t *)pte_fragment_alloc(mm, address, 1);
+	return (pte_t *)pte_fragment_alloc(mm, 1);
 }
 
-pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
+pgtable_t pte_alloc_one(struct mm_struct *mm)
 {
-	return (pgtable_t)pte_fragment_alloc(mm, address, 0);
+	return (pgtable_t)pte_fragment_alloc(mm, 0);
 }
 
 void __iomem *