[PATCH 0/7] powerpc/mm: refactor vDSO mapping code

[PATCH 0/7] powerpc/mm: refactor vDSO mapping code

[Dmitry Safonov]

Cleanup patches for vDSO on powerpc.
Originally, I wanted to add vDSO remapping on arm/aarch64 and
I decided to cleanup that part on powerpc.
I've add a hook for vm_ops for vDSO just like I did for x86.
Other changes - reduce exhaustive code duplication.
No visible to userspace changes expected.

Tested on qemu with buildroot rootfs.

Dmitry Safonov (7):
  powerpc/vdso: unify return paths in setup_additional_pages
  powerpc/vdso: remove unused params in vdso_do_func_patch{32,64}
  powerpc/vdso: separate common code in vdso_common
  powerpc/vdso: introduce init_vdso{32,64}_pagelist
  powerpc/vdso: split map_vdso from arch_setup_additional_pages
  powerpc/vdso: switch from legacy_special_mapping_vmops
  mm: kill arch_mremap

 arch/alpha/include/asm/Kbuild            |   1 -
 arch/arc/include/asm/Kbuild              |   1 -
 arch/arm/include/asm/Kbuild              |   1 -
 arch/arm64/include/asm/Kbuild            |   1 -
 arch/avr32/include/asm/Kbuild            |   1 -
 arch/blackfin/include/asm/Kbuild         |   1 -
 arch/c6x/include/asm/Kbuild              |   1 -
 arch/cris/include/asm/Kbuild             |   1 -
 arch/frv/include/asm/Kbuild              |   1 -
 arch/h8300/include/asm/Kbuild            |   1 -
 arch/hexagon/include/asm/Kbuild          |   1 -
 arch/ia64/include/asm/Kbuild             |   1 -
 arch/m32r/include/asm/Kbuild             |   1 -
 arch/m68k/include/asm/Kbuild             |   1 -
 arch/metag/include/asm/Kbuild            |   1 -
 arch/microblaze/include/asm/Kbuild       |   1 -
 arch/mips/include/asm/Kbuild             |   1 -
 arch/mn10300/include/asm/Kbuild          |   1 -
 arch/nios2/include/asm/Kbuild            |   1 -
 arch/openrisc/include/asm/Kbuild         |   1 -
 arch/parisc/include/asm/Kbuild           |   1 -
 arch/powerpc/include/asm/mm-arch-hooks.h |  28 --
 arch/powerpc/kernel/vdso.c               | 492 +++++--------------------------
 arch/powerpc/kernel/vdso_common.c        | 248 ++++++++++++++++
 arch/s390/include/asm/Kbuild             |   1 -
 arch/score/include/asm/Kbuild            |   1 -
 arch/sh/include/asm/Kbuild               |   1 -
 arch/sparc/include/asm/Kbuild            |   1 -
 arch/tile/include/asm/Kbuild             |   1 -
 arch/um/include/asm/Kbuild               |   1 -
 arch/unicore32/include/asm/Kbuild        |   1 -
 arch/x86/include/asm/Kbuild              |   1 -
 arch/xtensa/include/asm/Kbuild           |   1 -
 include/asm-generic/mm-arch-hooks.h      |  16 -
 include/linux/mm-arch-hooks.h            |  25 --
 mm/mremap.c                              |   4 -
 36 files changed, 323 insertions(+), 520 deletions(-)
 delete mode 100644 arch/powerpc/include/asm/mm-arch-hooks.h
 create mode 100644 arch/powerpc/kernel/vdso_common.c
 delete mode 100644 include/asm-generic/mm-arch-hooks.h
 delete mode 100644 include/linux/mm-arch-hooks.h

-- 
2.10.0

[PATCH 1/7] powerpc/vdso: unify return paths in setup_additional_pages

[Dmitry Safonov]

Impact: cleanup

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-mm@kvack.org 
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
---
 arch/powerpc/kernel/vdso.c | 19 +++++++------------
 1 file changed, 7 insertions(+), 12 deletions(-)

diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 4111d30badfa..4ffb82a2d9e9 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -154,7 +154,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 	struct page **vdso_pagelist;
 	unsigned long vdso_pages;
 	unsigned long vdso_base;
-	int rc;
+	int ret = 0;
 
 	if (!vdso_ready)
 		return 0;
@@ -203,8 +203,8 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 				      ((VDSO_ALIGNMENT - 1) & PAGE_MASK),
 				      0, 0);
 	if (IS_ERR_VALUE(vdso_base)) {
-		rc = vdso_base;
-		goto fail_mmapsem;
+		ret = vdso_base;
+		goto out_up_mmap_sem;
 	}
 
 	/* Add required alignment. */
@@ -227,21 +227,16 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 	 * It's fine to use that for setting breakpoints in the vDSO code
 	 * pages though.
 	 */
-	rc = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
+	ret = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
 				     VM_READ|VM_EXEC|
 				     VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
 				     vdso_pagelist);
-	if (rc) {
+	if (ret)
 		current->mm->context.vdso_base = 0;
-		goto fail_mmapsem;
-	}
-
-	up_write(&mm->mmap_sem);
-	return 0;
 
- fail_mmapsem:
+out_up_mmap_sem:
 	up_write(&mm->mmap_sem);
-	return rc;
+	return ret;
 }
 
 const char *arch_vma_name(struct vm_area_struct *vma)
-- 
2.10.0

[PATCH 2/7] powerpc/vdso: remove unused params in vdso_do_func_patch{32,64}

[Dmitry Safonov]

Impact: cleanup

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-mm@kvack.org 
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
---
 arch/powerpc/kernel/vdso.c | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 4ffb82a2d9e9..278b9aa25a1c 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -309,7 +309,6 @@ static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 }
 
 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
-				       struct lib64_elfinfo *v64,
 				       const char *orig, const char *fix)
 {
 	Elf32_Sym *sym32_gen, *sym32_fix;
@@ -344,7 +343,6 @@ static unsigned long __init find_function32(struct lib32_elfinfo *lib,
 }
 
 static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
-				       struct lib64_elfinfo *v64,
 				       const char *orig, const char *fix)
 {
 	return 0;
@@ -419,8 +417,7 @@ static unsigned long __init find_function64(struct lib64_elfinfo *lib,
 #endif
 }
 
-static int __init vdso_do_func_patch64(struct lib32_elfinfo *v32,
-				       struct lib64_elfinfo *v64,
+static int __init vdso_do_func_patch64(struct lib64_elfinfo *v64,
 				       const char *orig, const char *fix)
 {
 	Elf64_Sym *sym64_gen, *sym64_fix;
@@ -619,11 +616,9 @@ static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 		 * It would be easy to do, but doesn't seem to be necessary,
 		 * patching the OPD symbol is enough.
 		 */
-		vdso_do_func_patch32(v32, v64, patch->gen_name,
-				     patch->fix_name);
+		vdso_do_func_patch32(v32, patch->gen_name, patch->fix_name);
 #ifdef CONFIG_PPC64
-		vdso_do_func_patch64(v32, v64, patch->gen_name,
-				     patch->fix_name);
+		vdso_do_func_patch64(v64, patch->gen_name, patch->fix_name);
 #endif /* CONFIG_PPC64 */
 	}
 
-- 
2.10.0

[PATCH 3/7] powerpc/vdso: separate common code in vdso_common

[Dmitry Safonov]

Impact: cleanup

I also switched usage of printk(KERNEL_<LEVEL>,...) on pr_<level>(...)
and used pr_fmt() macro for "vDSO{32,64}: " prefix.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-mm@kvack.org 
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
---
 arch/powerpc/kernel/vdso.c        | 352 ++------------------------------------
 arch/powerpc/kernel/vdso_common.c | 221 ++++++++++++++++++++++++
 2 files changed, 234 insertions(+), 339 deletions(-)
 create mode 100644 arch/powerpc/kernel/vdso_common.c

diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 278b9aa25a1c..8010a0d82049 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -51,13 +51,13 @@
 #define VDSO_ALIGNMENT	(1 << 16)
 
 static unsigned int vdso32_pages;
-static void *vdso32_kbase;
 static struct page **vdso32_pagelist;
 unsigned long vdso32_sigtramp;
 unsigned long vdso32_rt_sigtramp;
 
 #ifdef CONFIG_VDSO32
 extern char vdso32_start, vdso32_end;
+static void *vdso32_kbase;
 #endif
 
 #ifdef CONFIG_PPC64
@@ -246,250 +246,16 @@ const char *arch_vma_name(struct vm_area_struct *vma)
 	return NULL;
 }
 
-
-
 #ifdef CONFIG_VDSO32
-static void * __init find_section32(Elf32_Ehdr *ehdr, const char *secname,
-				  unsigned long *size)
-{
-	Elf32_Shdr *sechdrs;
-	unsigned int i;
-	char *secnames;
-
-	/* Grab section headers and strings so we can tell who is who */
-	sechdrs = (void *)ehdr + ehdr->e_shoff;
-	secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
-
-	/* Find the section they want */
-	for (i = 1; i < ehdr->e_shnum; i++) {
-		if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
-			if (size)
-				*size = sechdrs[i].sh_size;
-			return (void *)ehdr + sechdrs[i].sh_offset;
-		}
-	}
-	*size = 0;
-	return NULL;
-}
-
-static Elf32_Sym * __init find_symbol32(struct lib32_elfinfo *lib,
-					const char *symname)
-{
-	unsigned int i;
-	char name[MAX_SYMNAME], *c;
-
-	for (i = 0; i < (lib->dynsymsize / sizeof(Elf32_Sym)); i++) {
-		if (lib->dynsym[i].st_name == 0)
-			continue;
-		strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
-			MAX_SYMNAME);
-		c = strchr(name, '@');
-		if (c)
-			*c = 0;
-		if (strcmp(symname, name) == 0)
-			return &lib->dynsym[i];
-	}
-	return NULL;
-}
-
-/* Note that we assume the section is .text and the symbol is relative to
- * the library base
- */
-static unsigned long __init find_function32(struct lib32_elfinfo *lib,
-					    const char *symname)
-{
-	Elf32_Sym *sym = find_symbol32(lib, symname);
-
-	if (sym == NULL) {
-		printk(KERN_WARNING "vDSO32: function %s not found !\n",
-		       symname);
-		return 0;
-	}
-	return sym->st_value - VDSO32_LBASE;
-}
-
-static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
-				       const char *orig, const char *fix)
-{
-	Elf32_Sym *sym32_gen, *sym32_fix;
-
-	sym32_gen = find_symbol32(v32, orig);
-	if (sym32_gen == NULL) {
-		printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", orig);
-		return -1;
-	}
-	if (fix == NULL) {
-		sym32_gen->st_name = 0;
-		return 0;
-	}
-	sym32_fix = find_symbol32(v32, fix);
-	if (sym32_fix == NULL) {
-		printk(KERN_ERR "vDSO32: Can't find symbol %s !\n", fix);
-		return -1;
-	}
-	sym32_gen->st_value = sym32_fix->st_value;
-	sym32_gen->st_size = sym32_fix->st_size;
-	sym32_gen->st_info = sym32_fix->st_info;
-	sym32_gen->st_other = sym32_fix->st_other;
-	sym32_gen->st_shndx = sym32_fix->st_shndx;
-
-	return 0;
-}
-#else /* !CONFIG_VDSO32 */
-static unsigned long __init find_function32(struct lib32_elfinfo *lib,
-					    const char *symname)
-{
-	return 0;
-}
-
-static int __init vdso_do_func_patch32(struct lib32_elfinfo *v32,
-				       const char *orig, const char *fix)
-{
-	return 0;
-}
+#include "vdso_common.c"
 #endif /* CONFIG_VDSO32 */
 
-
 #ifdef CONFIG_PPC64
-
-static void * __init find_section64(Elf64_Ehdr *ehdr, const char *secname,
-				  unsigned long *size)
-{
-	Elf64_Shdr *sechdrs;
-	unsigned int i;
-	char *secnames;
-
-	/* Grab section headers and strings so we can tell who is who */
-	sechdrs = (void *)ehdr + ehdr->e_shoff;
-	secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
-
-	/* Find the section they want */
-	for (i = 1; i < ehdr->e_shnum; i++) {
-		if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
-			if (size)
-				*size = sechdrs[i].sh_size;
-			return (void *)ehdr + sechdrs[i].sh_offset;
-		}
-	}
-	if (size)
-		*size = 0;
-	return NULL;
-}
-
-static Elf64_Sym * __init find_symbol64(struct lib64_elfinfo *lib,
-					const char *symname)
-{
-	unsigned int i;
-	char name[MAX_SYMNAME], *c;
-
-	for (i = 0; i < (lib->dynsymsize / sizeof(Elf64_Sym)); i++) {
-		if (lib->dynsym[i].st_name == 0)
-			continue;
-		strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
-			MAX_SYMNAME);
-		c = strchr(name, '@');
-		if (c)
-			*c = 0;
-		if (strcmp(symname, name) == 0)
-			return &lib->dynsym[i];
-	}
-	return NULL;
-}
-
-/* Note that we assume the section is .text and the symbol is relative to
- * the library base
- */
-static unsigned long __init find_function64(struct lib64_elfinfo *lib,
-					    const char *symname)
-{
-	Elf64_Sym *sym = find_symbol64(lib, symname);
-
-	if (sym == NULL) {
-		printk(KERN_WARNING "vDSO64: function %s not found !\n",
-		       symname);
-		return 0;
-	}
-#ifdef VDS64_HAS_DESCRIPTORS
-	return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
-		VDSO64_LBASE;
-#else
-	return sym->st_value - VDSO64_LBASE;
-#endif
-}
-
-static int __init vdso_do_func_patch64(struct lib64_elfinfo *v64,
-				       const char *orig, const char *fix)
-{
-	Elf64_Sym *sym64_gen, *sym64_fix;
-
-	sym64_gen = find_symbol64(v64, orig);
-	if (sym64_gen == NULL) {
-		printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", orig);
-		return -1;
-	}
-	if (fix == NULL) {
-		sym64_gen->st_name = 0;
-		return 0;
-	}
-	sym64_fix = find_symbol64(v64, fix);
-	if (sym64_fix == NULL) {
-		printk(KERN_ERR "vDSO64: Can't find symbol %s !\n", fix);
-		return -1;
-	}
-	sym64_gen->st_value = sym64_fix->st_value;
-	sym64_gen->st_size = sym64_fix->st_size;
-	sym64_gen->st_info = sym64_fix->st_info;
-	sym64_gen->st_other = sym64_fix->st_other;
-	sym64_gen->st_shndx = sym64_fix->st_shndx;
-
-	return 0;
-}
-
+#define BITS 64
+#include "vdso_common.c"
 #endif /* CONFIG_PPC64 */
 
 
-static __init int vdso_do_find_sections(struct lib32_elfinfo *v32,
-					struct lib64_elfinfo *v64)
-{
-	void *sect;
-
-	/*
-	 * Locate symbol tables & text section
-	 */
-
-#ifdef CONFIG_VDSO32
-	v32->dynsym = find_section32(v32->hdr, ".dynsym", &v32->dynsymsize);
-	v32->dynstr = find_section32(v32->hdr, ".dynstr", NULL);
-	if (v32->dynsym == NULL || v32->dynstr == NULL) {
-		printk(KERN_ERR "vDSO32: required symbol section not found\n");
-		return -1;
-	}
-	sect = find_section32(v32->hdr, ".text", NULL);
-	if (sect == NULL) {
-		printk(KERN_ERR "vDSO32: the .text section was not found\n");
-		return -1;
-	}
-	v32->text = sect - vdso32_kbase;
-#endif
-
-#ifdef CONFIG_PPC64
-	v64->dynsym = find_section64(v64->hdr, ".dynsym", &v64->dynsymsize);
-	v64->dynstr = find_section64(v64->hdr, ".dynstr", NULL);
-	if (v64->dynsym == NULL || v64->dynstr == NULL) {
-		printk(KERN_ERR "vDSO64: required symbol section not found\n");
-		return -1;
-	}
-	sect = find_section64(v64->hdr, ".text", NULL);
-	if (sect == NULL) {
-		printk(KERN_ERR "vDSO64: the .text section was not found\n");
-		return -1;
-	}
-	v64->text = sect - vdso64_kbase;
-#endif /* CONFIG_PPC64 */
-
-	return 0;
-}
-
 static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 					  struct lib64_elfinfo *v64)
 {
@@ -500,99 +266,10 @@ static __init void vdso_setup_trampolines(struct lib32_elfinfo *v32,
 #ifdef CONFIG_PPC64
 	vdso64_rt_sigtramp = find_function64(v64, "__kernel_sigtramp_rt64");
 #endif
+#ifdef CONFIG_VDSO32
 	vdso32_sigtramp	   = find_function32(v32, "__kernel_sigtramp32");
 	vdso32_rt_sigtramp = find_function32(v32, "__kernel_sigtramp_rt32");
-}
-
-static __init int vdso_fixup_datapage(struct lib32_elfinfo *v32,
-				       struct lib64_elfinfo *v64)
-{
-#ifdef CONFIG_VDSO32
-	Elf32_Sym *sym32;
-#endif
-#ifdef CONFIG_PPC64
-	Elf64_Sym *sym64;
-
-       	sym64 = find_symbol64(v64, "__kernel_datapage_offset");
-	if (sym64 == NULL) {
-		printk(KERN_ERR "vDSO64: Can't find symbol "
-		       "__kernel_datapage_offset !\n");
-		return -1;
-	}
-	*((int *)(vdso64_kbase + sym64->st_value - VDSO64_LBASE)) =
-		(vdso64_pages << PAGE_SHIFT) -
-		(sym64->st_value - VDSO64_LBASE);
-#endif /* CONFIG_PPC64 */
-
-#ifdef CONFIG_VDSO32
-	sym32 = find_symbol32(v32, "__kernel_datapage_offset");
-	if (sym32 == NULL) {
-		printk(KERN_ERR "vDSO32: Can't find symbol "
-		       "__kernel_datapage_offset !\n");
-		return -1;
-	}
-	*((int *)(vdso32_kbase + (sym32->st_value - VDSO32_LBASE))) =
-		(vdso32_pages << PAGE_SHIFT) -
-		(sym32->st_value - VDSO32_LBASE);
 #endif
-
-	return 0;
-}
-
-
-static __init int vdso_fixup_features(struct lib32_elfinfo *v32,
-				      struct lib64_elfinfo *v64)
-{
-	unsigned long size;
-	void *start;
-
-#ifdef CONFIG_PPC64
-	start = find_section64(v64->hdr, "__ftr_fixup", &size);
-	if (start)
-		do_feature_fixups(cur_cpu_spec->cpu_features,
-				  start, start + size);
-
-	start = find_section64(v64->hdr, "__mmu_ftr_fixup", &size);
-	if (start)
-		do_feature_fixups(cur_cpu_spec->mmu_features,
-				  start, start + size);
-
-	start = find_section64(v64->hdr, "__fw_ftr_fixup", &size);
-	if (start)
-		do_feature_fixups(powerpc_firmware_features,
-				  start, start + size);
-
-	start = find_section64(v64->hdr, "__lwsync_fixup", &size);
-	if (start)
-		do_lwsync_fixups(cur_cpu_spec->cpu_features,
-				 start, start + size);
-#endif /* CONFIG_PPC64 */
-
-#ifdef CONFIG_VDSO32
-	start = find_section32(v32->hdr, "__ftr_fixup", &size);
-	if (start)
-		do_feature_fixups(cur_cpu_spec->cpu_features,
-				  start, start + size);
-
-	start = find_section32(v32->hdr, "__mmu_ftr_fixup", &size);
-	if (start)
-		do_feature_fixups(cur_cpu_spec->mmu_features,
-				  start, start + size);
-
-#ifdef CONFIG_PPC64
-	start = find_section32(v32->hdr, "__fw_ftr_fixup", &size);
-	if (start)
-		do_feature_fixups(powerpc_firmware_features,
-				  start, start + size);
-#endif /* CONFIG_PPC64 */
-
-	start = find_section32(v32->hdr, "__lwsync_fixup", &size);
-	if (start)
-		do_lwsync_fixups(cur_cpu_spec->cpu_features,
-				 start, start + size);
-#endif
-
-	return 0;
 }
 
 static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
@@ -616,7 +293,9 @@ static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 		 * It would be easy to do, but doesn't seem to be necessary,
 		 * patching the OPD symbol is enough.
 		 */
+#ifdef CONFIG_VDSO32
 		vdso_do_func_patch32(v32, patch->gen_name, patch->fix_name);
+#endif
 #ifdef CONFIG_PPC64
 		vdso_do_func_patch64(v64, patch->gen_name, patch->fix_name);
 #endif /* CONFIG_PPC64 */
@@ -625,24 +304,19 @@ static __init int vdso_fixup_alt_funcs(struct lib32_elfinfo *v32,
 	return 0;
 }
 
-
 static __init int vdso_setup(void)
 {
 	struct lib32_elfinfo	v32;
 	struct lib64_elfinfo	v64;
 
-	v32.hdr = vdso32_kbase;
-#ifdef CONFIG_PPC64
-	v64.hdr = vdso64_kbase;
-#endif
-	if (vdso_do_find_sections(&v32, &v64))
-		return -1;
-
-	if (vdso_fixup_datapage(&v32, &v64))
+#ifdef CONFIG_VDSO32
+	if (vdso_setup32(&v32))
 		return -1;
-
-	if (vdso_fixup_features(&v32, &v64))
+#endif
+#ifdef CONFIG_PPC64
+	if (vdso_setup64(&v64))
 		return -1;
+#endif
 
 	if (vdso_fixup_alt_funcs(&v32, &v64))
 		return -1;
diff --git a/arch/powerpc/kernel/vdso_common.c b/arch/powerpc/kernel/vdso_common.c
new file mode 100644
index 000000000000..ac25d66134fb
--- /dev/null
+++ b/arch/powerpc/kernel/vdso_common.c
@@ -0,0 +1,221 @@
+#ifndef BITS
+#define BITS 32
+#endif
+
+#undef Elf_Ehdr
+#undef Elf_Sym
+#undef Elf_Shdr
+
+#define _CONCAT3(a, b, c)	a ## b ## c
+#define CONCAT3(a, b, c)	_CONCAT3(a, b, c)
+#define Elf_Ehdr	CONCAT3(Elf,  BITS, _Ehdr)
+#define Elf_Sym		CONCAT3(Elf,  BITS, _Sym)
+#define Elf_Shdr	CONCAT3(Elf,  BITS, _Shdr)
+#define VDSO_LBASE	CONCAT3(VDSO, BITS, _LBASE)
+#define vdso_kbase	CONCAT3(vdso, BITS, _kbase)
+#define vdso_pages	CONCAT3(vdso, BITS, _pages)
+
+#undef pr_fmt
+#define pr_fmt(fmt)	"vDSO" __stringify(BITS) ": " fmt
+
+#define lib_elfinfo CONCAT3(lib, BITS, _elfinfo)
+
+#define find_section CONCAT3(find_section, BITS,)
+static void * __init find_section(Elf_Ehdr *ehdr, const char *secname,
+		unsigned long *size)
+{
+	Elf_Shdr *sechdrs;
+	unsigned int i;
+	char *secnames;
+
+	/* Grab section headers and strings so we can tell who is who */
+	sechdrs = (void *)ehdr + ehdr->e_shoff;
+	secnames = (void *)ehdr + sechdrs[ehdr->e_shstrndx].sh_offset;
+
+	/* Find the section they want */
+	for (i = 1; i < ehdr->e_shnum; i++) {
+		if (strcmp(secnames+sechdrs[i].sh_name, secname) == 0) {
+			if (size)
+				*size = sechdrs[i].sh_size;
+			return (void *)ehdr + sechdrs[i].sh_offset;
+		}
+	}
+	if (size)
+		*size = 0;
+	return NULL;
+}
+
+#define find_symbol CONCAT3(find_symbol, BITS,)
+static Elf_Sym * __init find_symbol(struct lib_elfinfo *lib,
+		const char *symname)
+{
+	unsigned int i;
+	char name[MAX_SYMNAME], *c;
+
+	for (i = 0; i < (lib->dynsymsize / sizeof(Elf_Sym)); i++) {
+		if (lib->dynsym[i].st_name == 0)
+			continue;
+		strlcpy(name, lib->dynstr + lib->dynsym[i].st_name,
+			MAX_SYMNAME);
+		c = strchr(name, '@');
+		if (c)
+			*c = 0;
+		if (strcmp(symname, name) == 0)
+			return &lib->dynsym[i];
+	}
+	return NULL;
+}
+
+/*
+ * Note that we assume the section is .text and the symbol is relative to
+ * the library base.
+ */
+#define find_function CONCAT3(find_function, BITS,)
+static unsigned long __init find_function(struct lib_elfinfo *lib,
+		const char *symname)
+{
+	Elf_Sym *sym = find_symbol(lib, symname);
+
+	if (sym == NULL) {
+		pr_warn("function %s not found !\n", symname);
+		return 0;
+	}
+#if defined(VDS64_HAS_DESCRIPTORS) && (BITS == 64)
+	return *((u64 *)(vdso64_kbase + sym->st_value - VDSO64_LBASE)) -
+		VDSO64_LBASE;
+#else
+	return sym->st_value - VDSO_LBASE;
+#endif
+}
+
+#define vdso_do_func_patch CONCAT3(vdso_do_func_patch, BITS,)
+static int __init vdso_do_func_patch(struct lib_elfinfo *v,
+		const char *orig, const char *fix)
+{
+	Elf_Sym *sym_gen, *sym_fix;
+
+	sym_gen = find_symbol(v, orig);
+	if (sym_gen == NULL) {
+		pr_err("Can't find symbol %s !\n", orig);
+		return -1;
+	}
+	if (fix == NULL) {
+		sym_gen->st_name = 0;
+		return 0;
+	}
+	sym_fix = find_symbol(v, fix);
+	if (sym_fix == NULL) {
+		pr_err("Can't find symbol %s !\n", fix);
+		return -1;
+	}
+	sym_gen->st_value = sym_fix->st_value;
+	sym_gen->st_size = sym_fix->st_size;
+	sym_gen->st_info = sym_fix->st_info;
+	sym_gen->st_other = sym_fix->st_other;
+	sym_gen->st_shndx = sym_fix->st_shndx;
+
+	return 0;
+}
+
+#define vdso_do_find_sections CONCAT3(vdso_do_find_sections, BITS,)
+static __init int vdso_do_find_sections(struct lib_elfinfo *v)
+{
+	void *sect;
+
+	/*
+	 * Locate symbol tables & text section
+	 */
+	v->dynsym = find_section(v->hdr, ".dynsym", &v->dynsymsize);
+	v->dynstr = find_section(v->hdr, ".dynstr", NULL);
+	if (v->dynsym == NULL || v->dynstr == NULL) {
+		pr_err("required symbol section not found\n");
+		return -1;
+	}
+
+	sect = find_section(v->hdr, ".text", NULL);
+	if (sect == NULL) {
+		pr_err("the .text section was not found\n");
+		return -1;
+	}
+	v->text = sect - vdso_kbase;
+
+	return 0;
+}
+
+#define vdso_fixup_datapage CONCAT3(vdso_fixup_datapage, BITS,)
+static __init int vdso_fixup_datapage(struct lib_elfinfo *v)
+{
+	Elf_Sym *sym = find_symbol(v, "__kernel_datapage_offset");
+
+	if (sym == NULL) {
+		pr_err("Can't find symbol __kernel_datapage_offset !\n");
+		return -1;
+	}
+	*((int *)(vdso_kbase + sym->st_value - VDSO_LBASE)) =
+		(vdso_pages << PAGE_SHIFT) - (sym->st_value - VDSO_LBASE);
+
+	return 0;
+}
+
+#define vdso_fixup_features CONCAT3(vdso_fixup_features, BITS,)
+static __init int vdso_fixup_features(struct lib_elfinfo *v)
+{
+	unsigned long size;
+	void *start;
+
+	start = find_section(v->hdr, "__ftr_fixup", &size);
+	if (start)
+		do_feature_fixups(cur_cpu_spec->cpu_features,
+				  start, start + size);
+
+	start = find_section(v->hdr, "__mmu_ftr_fixup", &size);
+	if (start)
+		do_feature_fixups(cur_cpu_spec->mmu_features,
+				  start, start + size);
+
+#ifdef CONFIG_PPC64
+	start = find_section(v->hdr, "__fw_ftr_fixup", &size);
+	if (start)
+		do_feature_fixups(powerpc_firmware_features,
+				  start, start + size);
+#endif /* CONFIG_PPC64 */
+
+	start = find_section(v->hdr, "__lwsync_fixup", &size);
+	if (start)
+		do_lwsync_fixups(cur_cpu_spec->cpu_features,
+				 start, start + size);
+
+	return 0;
+}
+
+#define vdso_setup CONCAT3(vdso_setup, BITS,)
+static __init int vdso_setup(struct lib_elfinfo *v)
+{
+	v->hdr = vdso_kbase;
+
+	if (vdso_do_find_sections(v))
+		return -1;
+	if (vdso_fixup_datapage(v))
+		return -1;
+	if (vdso_fixup_features(v))
+		return -1;
+	return 0;
+}
+
+
+#undef find_section
+#undef find_symbol
+#undef find_function
+#undef vdso_do_func_patch
+#undef vdso_do_find_sections
+#undef vdso_fixup_datapage
+#undef vdso_fixup_features
+#undef vdso_setup
+
+#undef VDSO_LBASE
+#undef vdso_kbase
+#undef vdso_pages
+#undef lib_elfinfo
+#undef BITS
+#undef _CONCAT3
+#undef CONCAT3
-- 
2.10.0

[PATCH 4/7] powerpc/vdso: introduce init_vdso{32,64}_pagelist

[Dmitry Safonov]

Common code with allocation/initialization of vDSO's pagelist.

Impact: cleanup

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-mm@kvack.org 
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
---
 arch/powerpc/kernel/vdso.c        | 27 ++-------------------------
 arch/powerpc/kernel/vdso_common.c | 22 ++++++++++++++++++++++
 2 files changed, 24 insertions(+), 25 deletions(-)

diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 8010a0d82049..25d03d773c49 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -382,8 +382,6 @@ early_initcall(vdso_getcpu_init);
 
 static int __init vdso_init(void)
 {
-	int i;
-
 #ifdef CONFIG_PPC64
 	/*
 	 * Fill up the "systemcfg" stuff for backward compatibility
@@ -454,32 +452,11 @@ static int __init vdso_init(void)
 	}
 
 #ifdef CONFIG_VDSO32
-	/* Make sure pages are in the correct state */
-	vdso32_pagelist = kzalloc(sizeof(struct page *) * (vdso32_pages + 2),
-				  GFP_KERNEL);
-	BUG_ON(vdso32_pagelist == NULL);
-	for (i = 0; i < vdso32_pages; i++) {
-		struct page *pg = virt_to_page(vdso32_kbase + i*PAGE_SIZE);
-		ClearPageReserved(pg);
-		get_page(pg);
-		vdso32_pagelist[i] = pg;
-	}
-	vdso32_pagelist[i++] = virt_to_page(vdso_data);
-	vdso32_pagelist[i] = NULL;
+	init_vdso32_pagelist();
 #endif
 
 #ifdef CONFIG_PPC64
-	vdso64_pagelist = kzalloc(sizeof(struct page *) * (vdso64_pages + 2),
-				  GFP_KERNEL);
-	BUG_ON(vdso64_pagelist == NULL);
-	for (i = 0; i < vdso64_pages; i++) {
-		struct page *pg = virt_to_page(vdso64_kbase + i*PAGE_SIZE);
-		ClearPageReserved(pg);
-		get_page(pg);
-		vdso64_pagelist[i] = pg;
-	}
-	vdso64_pagelist[i++] = virt_to_page(vdso_data);
-	vdso64_pagelist[i] = NULL;
+	init_vdso64_pagelist();
 #endif /* CONFIG_PPC64 */
 
 	get_page(virt_to_page(vdso_data));
diff --git a/arch/powerpc/kernel/vdso_common.c b/arch/powerpc/kernel/vdso_common.c
index ac25d66134fb..c97c30606b3f 100644
--- a/arch/powerpc/kernel/vdso_common.c
+++ b/arch/powerpc/kernel/vdso_common.c
@@ -14,6 +14,7 @@
 #define VDSO_LBASE	CONCAT3(VDSO, BITS, _LBASE)
 #define vdso_kbase	CONCAT3(vdso, BITS, _kbase)
 #define vdso_pages	CONCAT3(vdso, BITS, _pages)
+#define vdso_pagelist	CONCAT3(vdso, BITS, _pagelist)
 
 #undef pr_fmt
 #define pr_fmt(fmt)	"vDSO" __stringify(BITS) ": " fmt
@@ -202,6 +203,25 @@ static __init int vdso_setup(struct lib_elfinfo *v)
 	return 0;
 }
 
+#define init_vdso_pagelist CONCAT3(init_vdso, BITS, _pagelist)
+static __init void init_vdso_pagelist(void)
+{
+	int i;
+
+	/* Make sure pages are in the correct state */
+	vdso_pagelist = kzalloc(sizeof(struct page *) * (vdso_pages + 2),
+				  GFP_KERNEL);
+	BUG_ON(vdso_pagelist == NULL);
+	for (i = 0; i < vdso_pages; i++) {
+		struct page *pg = virt_to_page(vdso_kbase + i*PAGE_SIZE);
+
+		ClearPageReserved(pg);
+		get_page(pg);
+		vdso_pagelist[i] = pg;
+	}
+	vdso_pagelist[i++] = virt_to_page(vdso_data);
+	vdso_pagelist[i] = NULL;
+}
 
 #undef find_section
 #undef find_symbol
@@ -211,10 +231,12 @@ static __init int vdso_setup(struct lib_elfinfo *v)
 #undef vdso_fixup_datapage
 #undef vdso_fixup_features
 #undef vdso_setup
+#undef init_vdso_pagelist
 
 #undef VDSO_LBASE
 #undef vdso_kbase
 #undef vdso_pages
+#undef vdso_pagelist
 #undef lib_elfinfo
 #undef BITS
 #undef _CONCAT3
-- 
2.10.0

[PATCH 5/7] powerpc/vdso: split map_vdso from arch_setup_additional_pages

[Dmitry Safonov]

I'll be easier to introduce vm_special_mapping struct in
a smaller map_vdso() function (see the next patches).

Impact: cleanup

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-mm@kvack.org 
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
---
 arch/powerpc/kernel/vdso.c | 67 +++++++++++++++++++++-------------------------
 1 file changed, 31 insertions(+), 36 deletions(-)

diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 25d03d773c49..e68601ffc9ad 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -143,52 +143,23 @@ struct lib64_elfinfo
 	unsigned long	text;
 };
 
-
-/*
- * This is called from binfmt_elf, we create the special vma for the
- * vDSO and insert it into the mm struct tree
- */
-int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
+static int map_vdso(struct page **vdso_pagelist, unsigned long vdso_pages,
+		unsigned long vdso_base)
 {
 	struct mm_struct *mm = current->mm;
-	struct page **vdso_pagelist;
-	unsigned long vdso_pages;
-	unsigned long vdso_base;
 	int ret = 0;
 
-	if (!vdso_ready)
-		return 0;
-
-#ifdef CONFIG_PPC64
-	if (is_32bit_task()) {
-		vdso_pagelist = vdso32_pagelist;
-		vdso_pages = vdso32_pages;
-		vdso_base = VDSO32_MBASE;
-	} else {
-		vdso_pagelist = vdso64_pagelist;
-		vdso_pages = vdso64_pages;
-		/*
-		 * On 64bit we don't have a preferred map address. This
-		 * allows get_unmapped_area to find an area near other mmaps
-		 * and most likely share a SLB entry.
-		 */
-		vdso_base = 0;
-	}
-#else
-	vdso_pagelist = vdso32_pagelist;
-	vdso_pages = vdso32_pages;
-	vdso_base = VDSO32_MBASE;
-#endif
-
-	current->mm->context.vdso_base = 0;
+	mm->context.vdso_base = 0;
 
-	/* vDSO has a problem and was disabled, just don't "enable" it for the
+	/*
+	 * vDSO has a problem and was disabled, just don't "enable" it for the
 	 * process
 	 */
 	if (vdso_pages == 0)
 		return 0;
+
 	/* Add a page to the vdso size for the data page */
-	vdso_pages ++;
+	vdso_pages++;
 
 	/*
 	 * pick a base address for the vDSO in process space. We try to put it
@@ -239,6 +210,30 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 	return ret;
 }
 
+/*
+ * This is called from binfmt_elf, we create the special vma for the
+ * vDSO and insert it into the mm struct tree
+ */
+int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
+{
+	if (!vdso_ready)
+		return 0;
+
+	if (is_32bit_task())
+		return map_vdso(vdso32_pagelist, vdso32_pages, VDSO32_MBASE);
+#ifdef CONFIG_PPC64
+	else
+		/*
+		 * On 64bit we don't have a preferred map address. This
+		 * allows get_unmapped_area to find an area near other mmaps
+		 * and most likely share a SLB entry.
+		 */
+		return map_vdso(vdso64_pagelist, vdso64_pages, 0);
+#endif
+	WARN_ONCE(1, "task is not 32-bit on non PPC64 kernel");
+	return -1;
+}
+
 const char *arch_vma_name(struct vm_area_struct *vma)
 {
 	if (vma->vm_mm && vma->vm_start == vma->vm_mm->context.vdso_base)
-- 
2.10.0

[PATCH 6/7] powerpc/vdso: switch from legacy_special_mapping_vmops

[Dmitry Safonov]

This will allow to introduce mremap hook (the next patch).

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-mm@kvack.org 
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
---
 arch/powerpc/kernel/vdso.c        | 19 +++++++++++--------
 arch/powerpc/kernel/vdso_common.c |  8 ++++++--
 2 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index e68601ffc9ad..9ee3fd65c6e9 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -51,7 +51,7 @@
 #define VDSO_ALIGNMENT	(1 << 16)
 
 static unsigned int vdso32_pages;
-static struct page **vdso32_pagelist;
+static struct vm_special_mapping vdso32_mapping;
 unsigned long vdso32_sigtramp;
 unsigned long vdso32_rt_sigtramp;
 
@@ -64,7 +64,7 @@ static void *vdso32_kbase;
 extern char vdso64_start, vdso64_end;
 static void *vdso64_kbase = &vdso64_start;
 static unsigned int vdso64_pages;
-static struct page **vdso64_pagelist;
+static struct vm_special_mapping vdso64_mapping;
 unsigned long vdso64_rt_sigtramp;
 #endif /* CONFIG_PPC64 */
 
@@ -143,10 +143,11 @@ struct lib64_elfinfo
 	unsigned long	text;
 };
 
-static int map_vdso(struct page **vdso_pagelist, unsigned long vdso_pages,
+static int map_vdso(struct vm_special_mapping *vsm, unsigned long vdso_pages,
 		unsigned long vdso_base)
 {
 	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
 	int ret = 0;
 
 	mm->context.vdso_base = 0;
@@ -198,12 +199,14 @@ static int map_vdso(struct page **vdso_pagelist, unsigned long vdso_pages,
 	 * It's fine to use that for setting breakpoints in the vDSO code
 	 * pages though.
 	 */
-	ret = install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
+	vma = _install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT,
 				     VM_READ|VM_EXEC|
 				     VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
-				     vdso_pagelist);
-	if (ret)
+				     vsm);
+	if (IS_ERR(vma)) {
+		ret = PTR_ERR(vma);
 		current->mm->context.vdso_base = 0;
+	}
 
 out_up_mmap_sem:
 	up_write(&mm->mmap_sem);
@@ -220,7 +223,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 		return 0;
 
 	if (is_32bit_task())
-		return map_vdso(vdso32_pagelist, vdso32_pages, VDSO32_MBASE);
+		return map_vdso(&vdso32_mapping, vdso32_pages, VDSO32_MBASE);
 #ifdef CONFIG_PPC64
 	else
 		/*
@@ -228,7 +231,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 		 * allows get_unmapped_area to find an area near other mmaps
 		 * and most likely share a SLB entry.
 		 */
-		return map_vdso(vdso64_pagelist, vdso64_pages, 0);
+		return map_vdso(&vdso64_mapping, vdso64_pages, 0);
 #endif
 	WARN_ONCE(1, "task is not 32-bit on non PPC64 kernel");
 	return -1;
diff --git a/arch/powerpc/kernel/vdso_common.c b/arch/powerpc/kernel/vdso_common.c
index c97c30606b3f..047f6b8b230f 100644
--- a/arch/powerpc/kernel/vdso_common.c
+++ b/arch/powerpc/kernel/vdso_common.c
@@ -14,7 +14,7 @@
 #define VDSO_LBASE	CONCAT3(VDSO, BITS, _LBASE)
 #define vdso_kbase	CONCAT3(vdso, BITS, _kbase)
 #define vdso_pages	CONCAT3(vdso, BITS, _pages)
-#define vdso_pagelist	CONCAT3(vdso, BITS, _pagelist)
+#define vdso_mapping	CONCAT3(vdso, BITS, _mapping)
 
 #undef pr_fmt
 #define pr_fmt(fmt)	"vDSO" __stringify(BITS) ": " fmt
@@ -207,6 +207,7 @@ static __init int vdso_setup(struct lib_elfinfo *v)
 static __init void init_vdso_pagelist(void)
 {
 	int i;
+	struct page **vdso_pagelist;
 
 	/* Make sure pages are in the correct state */
 	vdso_pagelist = kzalloc(sizeof(struct page *) * (vdso_pages + 2),
@@ -221,6 +222,9 @@ static __init void init_vdso_pagelist(void)
 	}
 	vdso_pagelist[i++] = virt_to_page(vdso_data);
 	vdso_pagelist[i] = NULL;
+
+	vdso_mapping.pages = vdso_pagelist;
+	vdso_mapping.name = "[vdso]";
 }
 
 #undef find_section
@@ -236,7 +240,7 @@ static __init void init_vdso_pagelist(void)
 #undef VDSO_LBASE
 #undef vdso_kbase
 #undef vdso_pages
-#undef vdso_pagelist
+#undef vdso_mapping
 #undef lib_elfinfo
 #undef BITS
 #undef _CONCAT3
-- 
2.10.0

[PATCH 7/7] mm: kill arch_mremap

[Dmitry Safonov]

This reverts commit 4abad2ca4a4d ("mm: new arch_remap() hook") and
commit 2ae416b142b6 ("mm: new mm hook framework").
It also keeps the same functionality of mremapping vDSO blob with
introducing vm_special_mapping mremap op for powerpc.

Cc: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-mm@kvack.org 
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
---
 arch/alpha/include/asm/Kbuild            |  1 -
 arch/arc/include/asm/Kbuild              |  1 -
 arch/arm/include/asm/Kbuild              |  1 -
 arch/arm64/include/asm/Kbuild            |  1 -
 arch/avr32/include/asm/Kbuild            |  1 -
 arch/blackfin/include/asm/Kbuild         |  1 -
 arch/c6x/include/asm/Kbuild              |  1 -
 arch/cris/include/asm/Kbuild             |  1 -
 arch/frv/include/asm/Kbuild              |  1 -
 arch/h8300/include/asm/Kbuild            |  1 -
 arch/hexagon/include/asm/Kbuild          |  1 -
 arch/ia64/include/asm/Kbuild             |  1 -
 arch/m32r/include/asm/Kbuild             |  1 -
 arch/m68k/include/asm/Kbuild             |  1 -
 arch/metag/include/asm/Kbuild            |  1 -
 arch/microblaze/include/asm/Kbuild       |  1 -
 arch/mips/include/asm/Kbuild             |  1 -
 arch/mn10300/include/asm/Kbuild          |  1 -
 arch/nios2/include/asm/Kbuild            |  1 -
 arch/openrisc/include/asm/Kbuild         |  1 -
 arch/parisc/include/asm/Kbuild           |  1 -
 arch/powerpc/include/asm/mm-arch-hooks.h | 28 ----------------------------
 arch/powerpc/kernel/vdso.c               | 19 +++++++++++++++++++
 arch/powerpc/kernel/vdso_common.c        |  1 +
 arch/s390/include/asm/Kbuild             |  1 -
 arch/score/include/asm/Kbuild            |  1 -
 arch/sh/include/asm/Kbuild               |  1 -
 arch/sparc/include/asm/Kbuild            |  1 -
 arch/tile/include/asm/Kbuild             |  1 -
 arch/um/include/asm/Kbuild               |  1 -
 arch/unicore32/include/asm/Kbuild        |  1 -
 arch/x86/include/asm/Kbuild              |  1 -
 arch/xtensa/include/asm/Kbuild           |  1 -
 include/asm-generic/mm-arch-hooks.h      | 16 ----------------
 include/linux/mm-arch-hooks.h            | 25 -------------------------
 mm/mremap.c                              |  4 ----
 36 files changed, 20 insertions(+), 103 deletions(-)
 delete mode 100644 arch/powerpc/include/asm/mm-arch-hooks.h
 delete mode 100644 include/asm-generic/mm-arch-hooks.h
 delete mode 100644 include/linux/mm-arch-hooks.h

diff --git a/arch/alpha/include/asm/Kbuild b/arch/alpha/include/asm/Kbuild
index bf8475ce85ee..0a5e0ec2842b 100644
--- a/arch/alpha/include/asm/Kbuild
+++ b/arch/alpha/include/asm/Kbuild
@@ -6,7 +6,6 @@ generic-y += exec.h
 generic-y += export.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += preempt.h
 generic-y += sections.h
 generic-y += trace_clock.h
diff --git a/arch/arc/include/asm/Kbuild b/arch/arc/include/asm/Kbuild
index c332604606dd..e6059a808463 100644
--- a/arch/arc/include/asm/Kbuild
+++ b/arch/arc/include/asm/Kbuild
@@ -22,7 +22,6 @@ generic-y += kvm_para.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += msgbuf.h
 generic-y += msi.h
diff --git a/arch/arm/include/asm/Kbuild b/arch/arm/include/asm/Kbuild
index 0745538b26d3..44b717cb4a55 100644
--- a/arch/arm/include/asm/Kbuild
+++ b/arch/arm/include/asm/Kbuild
@@ -15,7 +15,6 @@ generic-y += irq_regs.h
 generic-y += kdebug.h
 generic-y += local.h
 generic-y += local64.h
-generic-y += mm-arch-hooks.h
 generic-y += msgbuf.h
 generic-y += msi.h
 generic-y += param.h
diff --git a/arch/arm64/include/asm/Kbuild b/arch/arm64/include/asm/Kbuild
index 44e1d7f10add..a42a1367aea4 100644
--- a/arch/arm64/include/asm/Kbuild
+++ b/arch/arm64/include/asm/Kbuild
@@ -20,7 +20,6 @@ generic-y += kvm_para.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += msgbuf.h
 generic-y += msi.h
diff --git a/arch/avr32/include/asm/Kbuild b/arch/avr32/include/asm/Kbuild
index 241b9b9729d8..519810d0d5e1 100644
--- a/arch/avr32/include/asm/Kbuild
+++ b/arch/avr32/include/asm/Kbuild
@@ -12,7 +12,6 @@ generic-y += irq_work.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += param.h
 generic-y += percpu.h
 generic-y += preempt.h
diff --git a/arch/blackfin/include/asm/Kbuild b/arch/blackfin/include/asm/Kbuild
index 91d49c0a3118..c80181e4454f 100644
--- a/arch/blackfin/include/asm/Kbuild
+++ b/arch/blackfin/include/asm/Kbuild
@@ -21,7 +21,6 @@ generic-y += kvm_para.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += msgbuf.h
 generic-y += mutex.h
diff --git a/arch/c6x/include/asm/Kbuild b/arch/c6x/include/asm/Kbuild
index 64465e7e2245..1b9cbed76cdd 100644
--- a/arch/c6x/include/asm/Kbuild
+++ b/arch/c6x/include/asm/Kbuild
@@ -27,7 +27,6 @@ generic-y += kdebug.h
 generic-y += kmap_types.h
 generic-y += local.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += mmu.h
 generic-y += mmu_context.h
diff --git a/arch/cris/include/asm/Kbuild b/arch/cris/include/asm/Kbuild
index 1778805f6380..8e98d039780c 100644
--- a/arch/cris/include/asm/Kbuild
+++ b/arch/cris/include/asm/Kbuild
@@ -24,7 +24,6 @@ generic-y += linkage.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += module.h
 generic-y += msgbuf.h
diff --git a/arch/frv/include/asm/Kbuild b/arch/frv/include/asm/Kbuild
index 1fa084cf1a43..2c987dc05af4 100644
--- a/arch/frv/include/asm/Kbuild
+++ b/arch/frv/include/asm/Kbuild
@@ -4,7 +4,6 @@ generic-y += cputime.h
 generic-y += exec.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += preempt.h
 generic-y += trace_clock.h
 generic-y += word-at-a-time.h
diff --git a/arch/h8300/include/asm/Kbuild b/arch/h8300/include/asm/Kbuild
index 373cb23301e3..2a63a32366f0 100644
--- a/arch/h8300/include/asm/Kbuild
+++ b/arch/h8300/include/asm/Kbuild
@@ -33,7 +33,6 @@ generic-y += linkage.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += mmu.h
 generic-y += mmu_context.h
diff --git a/arch/hexagon/include/asm/Kbuild b/arch/hexagon/include/asm/Kbuild
index db8ddabc6bd2..0988816dded0 100644
--- a/arch/hexagon/include/asm/Kbuild
+++ b/arch/hexagon/include/asm/Kbuild
@@ -28,7 +28,6 @@ generic-y += kmap_types.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += msgbuf.h
 generic-y += pci.h
diff --git a/arch/ia64/include/asm/Kbuild b/arch/ia64/include/asm/Kbuild
index 502a91d8dbbd..dc05773e1f11 100644
--- a/arch/ia64/include/asm/Kbuild
+++ b/arch/ia64/include/asm/Kbuild
@@ -4,7 +4,6 @@ generic-y += exec.h
 generic-y += irq_work.h
 generic-y += kvm_para.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += preempt.h
 generic-y += trace_clock.h
 generic-y += vtime.h
diff --git a/arch/m32r/include/asm/Kbuild b/arch/m32r/include/asm/Kbuild
index 860e440611c9..f09a5fdb3b77 100644
--- a/arch/m32r/include/asm/Kbuild
+++ b/arch/m32r/include/asm/Kbuild
@@ -5,7 +5,6 @@ generic-y += exec.h
 generic-y += irq_work.h
 generic-y += kvm_para.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += module.h
 generic-y += preempt.h
 generic-y += sections.h
diff --git a/arch/m68k/include/asm/Kbuild b/arch/m68k/include/asm/Kbuild
index eb85bd9c6180..1555bc189c7d 100644
--- a/arch/m68k/include/asm/Kbuild
+++ b/arch/m68k/include/asm/Kbuild
@@ -18,7 +18,6 @@ generic-y += kvm_para.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += mutex.h
 generic-y += percpu.h
diff --git a/arch/metag/include/asm/Kbuild b/arch/metag/include/asm/Kbuild
index 29acb89daaaa..611c0df2be39 100644
--- a/arch/metag/include/asm/Kbuild
+++ b/arch/metag/include/asm/Kbuild
@@ -25,7 +25,6 @@ generic-y += kvm_para.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += msgbuf.h
 generic-y += mutex.h
 generic-y += param.h
diff --git a/arch/microblaze/include/asm/Kbuild b/arch/microblaze/include/asm/Kbuild
index b0ae88c9fed9..cefeabae24cc 100644
--- a/arch/microblaze/include/asm/Kbuild
+++ b/arch/microblaze/include/asm/Kbuild
@@ -6,7 +6,6 @@ generic-y += device.h
 generic-y += exec.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += preempt.h
 generic-y += syscalls.h
 generic-y += trace_clock.h
diff --git a/arch/mips/include/asm/Kbuild b/arch/mips/include/asm/Kbuild
index 9740066cc631..f0ce0ae0a358 100644
--- a/arch/mips/include/asm/Kbuild
+++ b/arch/mips/include/asm/Kbuild
@@ -8,7 +8,6 @@ generic-y += emergency-restart.h
 generic-y += irq_work.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mutex.h
 generic-y += parport.h
 generic-y += percpu.h
diff --git a/arch/mn10300/include/asm/Kbuild b/arch/mn10300/include/asm/Kbuild
index 1c8dd0f5cd5d..27cbc0267b9c 100644
--- a/arch/mn10300/include/asm/Kbuild
+++ b/arch/mn10300/include/asm/Kbuild
@@ -5,7 +5,6 @@ generic-y += cputime.h
 generic-y += exec.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += preempt.h
 generic-y += sections.h
 generic-y += trace_clock.h
diff --git a/arch/nios2/include/asm/Kbuild b/arch/nios2/include/asm/Kbuild
index d63330e88379..e22478929719 100644
--- a/arch/nios2/include/asm/Kbuild
+++ b/arch/nios2/include/asm/Kbuild
@@ -30,7 +30,6 @@ generic-y += kmap_types.h
 generic-y += kvm_para.h
 generic-y += local.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += module.h
 generic-y += msgbuf.h
diff --git a/arch/openrisc/include/asm/Kbuild b/arch/openrisc/include/asm/Kbuild
index 2832f031fb11..2a2e39b8109a 100644
--- a/arch/openrisc/include/asm/Kbuild
+++ b/arch/openrisc/include/asm/Kbuild
@@ -36,7 +36,6 @@ generic-y += kmap_types.h
 generic-y += kvm_para.h
 generic-y += local.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += module.h
 generic-y += msgbuf.h
diff --git a/arch/parisc/include/asm/Kbuild b/arch/parisc/include/asm/Kbuild
index f9b3a81aefcd..12b341d04f88 100644
--- a/arch/parisc/include/asm/Kbuild
+++ b/arch/parisc/include/asm/Kbuild
@@ -15,7 +15,6 @@ generic-y += kvm_para.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mutex.h
 generic-y += param.h
 generic-y += percpu.h
diff --git a/arch/powerpc/include/asm/mm-arch-hooks.h b/arch/powerpc/include/asm/mm-arch-hooks.h
deleted file mode 100644
index f2a2da895897..000000000000
--- a/arch/powerpc/include/asm/mm-arch-hooks.h
+++ /dev/null
@@ -1,28 +0,0 @@
-/*
- * Architecture specific mm hooks
- *
- * Copyright (C) 2015, IBM Corporation
- * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#ifndef _ASM_POWERPC_MM_ARCH_HOOKS_H
-#define _ASM_POWERPC_MM_ARCH_HOOKS_H
-
-static inline void arch_remap(struct mm_struct *mm,
-			      unsigned long old_start, unsigned long old_end,
-			      unsigned long new_start, unsigned long new_end)
-{
-	/*
-	 * mremap() doesn't allow moving multiple vmas so we can limit the
-	 * check to old_start == vdso_base.
-	 */
-	if (old_start == mm->context.vdso_base)
-		mm->context.vdso_base = new_start;
-}
-#define arch_remap arch_remap
-
-#endif /* _ASM_POWERPC_MM_ARCH_HOOKS_H */
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 9ee3fd65c6e9..6b6c5558d8e9 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -143,6 +143,25 @@ struct lib64_elfinfo
 	unsigned long	text;
 };
 
+static int vdso_mremap(const struct vm_special_mapping *sm,
+		struct vm_area_struct *new_vma)
+{
+	unsigned long new_size = new_vma->vm_end - new_vma->vm_start;
+	unsigned long vdso_pages = is_32bit_task() ?
+						vdso32_pages : vdso64_pages;
+
+	/* Do not allow partial remap, +1 is for vDSO data page */
+	if (new_size != (vdso_pages + 1) << PAGE_SHIFT)
+		return -EINVAL;
+
+	if (WARN_ON_ONCE(current->mm != new_vma->vm_mm))
+		return -EFAULT;
+
+	current->mm->context.vdso_base = new_vma->vm_start;
+
+	return 0;
+}
+
 static int map_vdso(struct vm_special_mapping *vsm, unsigned long vdso_pages,
 		unsigned long vdso_base)
 {
diff --git a/arch/powerpc/kernel/vdso_common.c b/arch/powerpc/kernel/vdso_common.c
index 047f6b8b230f..11fdf3e8acc7 100644
--- a/arch/powerpc/kernel/vdso_common.c
+++ b/arch/powerpc/kernel/vdso_common.c
@@ -225,6 +225,7 @@ static __init void init_vdso_pagelist(void)
 
 	vdso_mapping.pages = vdso_pagelist;
 	vdso_mapping.name = "[vdso]";
+	vdso_mapping.mremap = vdso_mremap;
 }
 
 #undef find_section
diff --git a/arch/s390/include/asm/Kbuild b/arch/s390/include/asm/Kbuild
index 20f196b82a6e..c1ef8252cc20 100644
--- a/arch/s390/include/asm/Kbuild
+++ b/arch/s390/include/asm/Kbuild
@@ -4,7 +4,6 @@ generic-y += clkdev.h
 generic-y += export.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += preempt.h
 generic-y += trace_clock.h
 generic-y += word-at-a-time.h
diff --git a/arch/score/include/asm/Kbuild b/arch/score/include/asm/Kbuild
index a05218ff3fe4..ff19975beb33 100644
--- a/arch/score/include/asm/Kbuild
+++ b/arch/score/include/asm/Kbuild
@@ -7,7 +7,6 @@ generic-y += clkdev.h
 generic-y += cputime.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += preempt.h
 generic-y += sections.h
 generic-y += trace_clock.h
diff --git a/arch/sh/include/asm/Kbuild b/arch/sh/include/asm/Kbuild
index 751c3373a92c..7d1fb2c7fcba 100644
--- a/arch/sh/include/asm/Kbuild
+++ b/arch/sh/include/asm/Kbuild
@@ -17,7 +17,6 @@ generic-y += kvm_para.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += msgbuf.h
 generic-y += param.h
diff --git a/arch/sparc/include/asm/Kbuild b/arch/sparc/include/asm/Kbuild
index cfc918067f80..0867d5ab7f87 100644
--- a/arch/sparc/include/asm/Kbuild
+++ b/arch/sparc/include/asm/Kbuild
@@ -13,7 +13,6 @@ generic-y += linkage.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += module.h
 generic-y += mutex.h
 generic-y += preempt.h
diff --git a/arch/tile/include/asm/Kbuild b/arch/tile/include/asm/Kbuild
index ba35c41c71ff..40d22b4a01f9 100644
--- a/arch/tile/include/asm/Kbuild
+++ b/arch/tile/include/asm/Kbuild
@@ -19,7 +19,6 @@ generic-y += irq_regs.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += msgbuf.h
 generic-y += mutex.h
 generic-y += param.h
diff --git a/arch/um/include/asm/Kbuild b/arch/um/include/asm/Kbuild
index 904f3ebf4220..33c1d3e0caad 100644
--- a/arch/um/include/asm/Kbuild
+++ b/arch/um/include/asm/Kbuild
@@ -16,7 +16,6 @@ generic-y += irq_regs.h
 generic-y += irq_work.h
 generic-y += kdebug.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mutex.h
 generic-y += param.h
 generic-y += pci.h
diff --git a/arch/unicore32/include/asm/Kbuild b/arch/unicore32/include/asm/Kbuild
index 256c45b3ae34..932070cd754a 100644
--- a/arch/unicore32/include/asm/Kbuild
+++ b/arch/unicore32/include/asm/Kbuild
@@ -26,7 +26,6 @@ generic-y += kdebug.h
 generic-y += kmap_types.h
 generic-y += local.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += module.h
 generic-y += msgbuf.h
diff --git a/arch/x86/include/asm/Kbuild b/arch/x86/include/asm/Kbuild
index 2cfed174e3c9..51b3d95f05e9 100644
--- a/arch/x86/include/asm/Kbuild
+++ b/arch/x86/include/asm/Kbuild
@@ -15,4 +15,3 @@ generic-y += cputime.h
 generic-y += dma-contiguous.h
 generic-y += early_ioremap.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
diff --git a/arch/xtensa/include/asm/Kbuild b/arch/xtensa/include/asm/Kbuild
index 28cf4c5d65ef..bdade9995e36 100644
--- a/arch/xtensa/include/asm/Kbuild
+++ b/arch/xtensa/include/asm/Kbuild
@@ -18,7 +18,6 @@ generic-y += linkage.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += percpu.h
 generic-y += preempt.h
 generic-y += resource.h
diff --git a/include/asm-generic/mm-arch-hooks.h b/include/asm-generic/mm-arch-hooks.h
deleted file mode 100644
index 5ff0e5193f85..000000000000
--- a/include/asm-generic/mm-arch-hooks.h
+++ /dev/null
@@ -1,16 +0,0 @@
-/*
- * Architecture specific mm hooks
- */
-
-#ifndef _ASM_GENERIC_MM_ARCH_HOOKS_H
-#define _ASM_GENERIC_MM_ARCH_HOOKS_H
-
-/*
- * This file should be included through arch/../include/asm/Kbuild for
- * the architecture which doesn't need specific mm hooks.
- *
- * In that case, the generic hooks defined in include/linux/mm-arch-hooks.h
- * are used.
- */
-
-#endif /* _ASM_GENERIC_MM_ARCH_HOOKS_H */
diff --git a/include/linux/mm-arch-hooks.h b/include/linux/mm-arch-hooks.h
deleted file mode 100644
index 4efc3f56e6df..000000000000
--- a/include/linux/mm-arch-hooks.h
+++ /dev/null
@@ -1,25 +0,0 @@
-/*
- * Generic mm no-op hooks.
- *
- * Copyright (C) 2015, IBM Corporation
- * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-#ifndef _LINUX_MM_ARCH_HOOKS_H
-#define _LINUX_MM_ARCH_HOOKS_H
-
-#include <asm/mm-arch-hooks.h>
-
-#ifndef arch_remap
-static inline void arch_remap(struct mm_struct *mm,
-			      unsigned long old_start, unsigned long old_end,
-			      unsigned long new_start, unsigned long new_end)
-{
-}
-#define arch_remap arch_remap
-#endif
-
-#endif /* _LINUX_MM_ARCH_HOOKS_H */
diff --git a/mm/mremap.c b/mm/mremap.c
index da22ad2a5678..5f1504c6cc77 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -21,7 +21,6 @@
 #include <linux/syscalls.h>
 #include <linux/mmu_notifier.h>
 #include <linux/uaccess.h>
-#include <linux/mm-arch-hooks.h>
 
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>
@@ -292,9 +291,6 @@ static unsigned long move_vma(struct vm_area_struct *vma,
 		old_len = new_len;
 		old_addr = new_addr;
 		new_addr = err;
-	} else {
-		arch_remap(mm, old_addr, old_addr + old_len,
-			   new_addr, new_addr + new_len);
 	}
 
 	/* Conceal VM_ACCOUNT so old reservation is not undone */
-- 
2.10.0

[PATCHv2 7/7] mm: kill arch_mremap

[Dmitry Safonov]

This reverts commit 4abad2ca4a4d ("mm: new arch_remap() hook") and
commit 2ae416b142b6 ("mm: new mm hook framework").
It also keeps the same functionality of mremapping vDSO blob with
introducing vm_special_mapping mremap op for powerpc.

Cc: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-mm@kvack.org 
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
---
v2: use vdso64_pages only under CONFIG_PPC64

 arch/alpha/include/asm/Kbuild            |  1 -
 arch/arc/include/asm/Kbuild              |  1 -
 arch/arm/include/asm/Kbuild              |  1 -
 arch/arm64/include/asm/Kbuild            |  1 -
 arch/avr32/include/asm/Kbuild            |  1 -
 arch/blackfin/include/asm/Kbuild         |  1 -
 arch/c6x/include/asm/Kbuild              |  1 -
 arch/cris/include/asm/Kbuild             |  1 -
 arch/frv/include/asm/Kbuild              |  1 -
 arch/h8300/include/asm/Kbuild            |  1 -
 arch/hexagon/include/asm/Kbuild          |  1 -
 arch/ia64/include/asm/Kbuild             |  1 -
 arch/m32r/include/asm/Kbuild             |  1 -
 arch/m68k/include/asm/Kbuild             |  1 -
 arch/metag/include/asm/Kbuild            |  1 -
 arch/microblaze/include/asm/Kbuild       |  1 -
 arch/mips/include/asm/Kbuild             |  1 -
 arch/mn10300/include/asm/Kbuild          |  1 -
 arch/nios2/include/asm/Kbuild            |  1 -
 arch/openrisc/include/asm/Kbuild         |  1 -
 arch/parisc/include/asm/Kbuild           |  1 -
 arch/powerpc/include/asm/mm-arch-hooks.h | 28 ----------------------------
 arch/powerpc/kernel/vdso.c               | 25 +++++++++++++++++++++++++
 arch/powerpc/kernel/vdso_common.c        |  1 +
 arch/s390/include/asm/Kbuild             |  1 -
 arch/score/include/asm/Kbuild            |  1 -
 arch/sh/include/asm/Kbuild               |  1 -
 arch/sparc/include/asm/Kbuild            |  1 -
 arch/tile/include/asm/Kbuild             |  1 -
 arch/um/include/asm/Kbuild               |  1 -
 arch/unicore32/include/asm/Kbuild        |  1 -
 arch/x86/include/asm/Kbuild              |  1 -
 arch/xtensa/include/asm/Kbuild           |  1 -
 include/asm-generic/mm-arch-hooks.h      | 16 ----------------
 include/linux/mm-arch-hooks.h            | 25 -------------------------
 mm/mremap.c                              |  4 ----
 36 files changed, 26 insertions(+), 103 deletions(-)
 delete mode 100644 arch/powerpc/include/asm/mm-arch-hooks.h
 delete mode 100644 include/asm-generic/mm-arch-hooks.h
 delete mode 100644 include/linux/mm-arch-hooks.h

diff --git a/arch/alpha/include/asm/Kbuild b/arch/alpha/include/asm/Kbuild
index bf8475ce85ee..0a5e0ec2842b 100644
--- a/arch/alpha/include/asm/Kbuild
+++ b/arch/alpha/include/asm/Kbuild
@@ -6,7 +6,6 @@ generic-y += exec.h
 generic-y += export.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += preempt.h
 generic-y += sections.h
 generic-y += trace_clock.h
diff --git a/arch/arc/include/asm/Kbuild b/arch/arc/include/asm/Kbuild
index c332604606dd..e6059a808463 100644
--- a/arch/arc/include/asm/Kbuild
+++ b/arch/arc/include/asm/Kbuild
@@ -22,7 +22,6 @@ generic-y += kvm_para.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += msgbuf.h
 generic-y += msi.h
diff --git a/arch/arm/include/asm/Kbuild b/arch/arm/include/asm/Kbuild
index 0745538b26d3..44b717cb4a55 100644
--- a/arch/arm/include/asm/Kbuild
+++ b/arch/arm/include/asm/Kbuild
@@ -15,7 +15,6 @@ generic-y += irq_regs.h
 generic-y += kdebug.h
 generic-y += local.h
 generic-y += local64.h
-generic-y += mm-arch-hooks.h
 generic-y += msgbuf.h
 generic-y += msi.h
 generic-y += param.h
diff --git a/arch/arm64/include/asm/Kbuild b/arch/arm64/include/asm/Kbuild
index 44e1d7f10add..a42a1367aea4 100644
--- a/arch/arm64/include/asm/Kbuild
+++ b/arch/arm64/include/asm/Kbuild
@@ -20,7 +20,6 @@ generic-y += kvm_para.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += msgbuf.h
 generic-y += msi.h
diff --git a/arch/avr32/include/asm/Kbuild b/arch/avr32/include/asm/Kbuild
index 241b9b9729d8..519810d0d5e1 100644
--- a/arch/avr32/include/asm/Kbuild
+++ b/arch/avr32/include/asm/Kbuild
@@ -12,7 +12,6 @@ generic-y += irq_work.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += param.h
 generic-y += percpu.h
 generic-y += preempt.h
diff --git a/arch/blackfin/include/asm/Kbuild b/arch/blackfin/include/asm/Kbuild
index 91d49c0a3118..c80181e4454f 100644
--- a/arch/blackfin/include/asm/Kbuild
+++ b/arch/blackfin/include/asm/Kbuild
@@ -21,7 +21,6 @@ generic-y += kvm_para.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += msgbuf.h
 generic-y += mutex.h
diff --git a/arch/c6x/include/asm/Kbuild b/arch/c6x/include/asm/Kbuild
index 64465e7e2245..1b9cbed76cdd 100644
--- a/arch/c6x/include/asm/Kbuild
+++ b/arch/c6x/include/asm/Kbuild
@@ -27,7 +27,6 @@ generic-y += kdebug.h
 generic-y += kmap_types.h
 generic-y += local.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += mmu.h
 generic-y += mmu_context.h
diff --git a/arch/cris/include/asm/Kbuild b/arch/cris/include/asm/Kbuild
index 1778805f6380..8e98d039780c 100644
--- a/arch/cris/include/asm/Kbuild
+++ b/arch/cris/include/asm/Kbuild
@@ -24,7 +24,6 @@ generic-y += linkage.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += module.h
 generic-y += msgbuf.h
diff --git a/arch/frv/include/asm/Kbuild b/arch/frv/include/asm/Kbuild
index 1fa084cf1a43..2c987dc05af4 100644
--- a/arch/frv/include/asm/Kbuild
+++ b/arch/frv/include/asm/Kbuild
@@ -4,7 +4,6 @@ generic-y += cputime.h
 generic-y += exec.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += preempt.h
 generic-y += trace_clock.h
 generic-y += word-at-a-time.h
diff --git a/arch/h8300/include/asm/Kbuild b/arch/h8300/include/asm/Kbuild
index 373cb23301e3..2a63a32366f0 100644
--- a/arch/h8300/include/asm/Kbuild
+++ b/arch/h8300/include/asm/Kbuild
@@ -33,7 +33,6 @@ generic-y += linkage.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += mmu.h
 generic-y += mmu_context.h
diff --git a/arch/hexagon/include/asm/Kbuild b/arch/hexagon/include/asm/Kbuild
index db8ddabc6bd2..0988816dded0 100644
--- a/arch/hexagon/include/asm/Kbuild
+++ b/arch/hexagon/include/asm/Kbuild
@@ -28,7 +28,6 @@ generic-y += kmap_types.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += msgbuf.h
 generic-y += pci.h
diff --git a/arch/ia64/include/asm/Kbuild b/arch/ia64/include/asm/Kbuild
index 502a91d8dbbd..dc05773e1f11 100644
--- a/arch/ia64/include/asm/Kbuild
+++ b/arch/ia64/include/asm/Kbuild
@@ -4,7 +4,6 @@ generic-y += exec.h
 generic-y += irq_work.h
 generic-y += kvm_para.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += preempt.h
 generic-y += trace_clock.h
 generic-y += vtime.h
diff --git a/arch/m32r/include/asm/Kbuild b/arch/m32r/include/asm/Kbuild
index 860e440611c9..f09a5fdb3b77 100644
--- a/arch/m32r/include/asm/Kbuild
+++ b/arch/m32r/include/asm/Kbuild
@@ -5,7 +5,6 @@ generic-y += exec.h
 generic-y += irq_work.h
 generic-y += kvm_para.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += module.h
 generic-y += preempt.h
 generic-y += sections.h
diff --git a/arch/m68k/include/asm/Kbuild b/arch/m68k/include/asm/Kbuild
index eb85bd9c6180..1555bc189c7d 100644
--- a/arch/m68k/include/asm/Kbuild
+++ b/arch/m68k/include/asm/Kbuild
@@ -18,7 +18,6 @@ generic-y += kvm_para.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += mutex.h
 generic-y += percpu.h
diff --git a/arch/metag/include/asm/Kbuild b/arch/metag/include/asm/Kbuild
index 29acb89daaaa..611c0df2be39 100644
--- a/arch/metag/include/asm/Kbuild
+++ b/arch/metag/include/asm/Kbuild
@@ -25,7 +25,6 @@ generic-y += kvm_para.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += msgbuf.h
 generic-y += mutex.h
 generic-y += param.h
diff --git a/arch/microblaze/include/asm/Kbuild b/arch/microblaze/include/asm/Kbuild
index b0ae88c9fed9..cefeabae24cc 100644
--- a/arch/microblaze/include/asm/Kbuild
+++ b/arch/microblaze/include/asm/Kbuild
@@ -6,7 +6,6 @@ generic-y += device.h
 generic-y += exec.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += preempt.h
 generic-y += syscalls.h
 generic-y += trace_clock.h
diff --git a/arch/mips/include/asm/Kbuild b/arch/mips/include/asm/Kbuild
index 9740066cc631..f0ce0ae0a358 100644
--- a/arch/mips/include/asm/Kbuild
+++ b/arch/mips/include/asm/Kbuild
@@ -8,7 +8,6 @@ generic-y += emergency-restart.h
 generic-y += irq_work.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mutex.h
 generic-y += parport.h
 generic-y += percpu.h
diff --git a/arch/mn10300/include/asm/Kbuild b/arch/mn10300/include/asm/Kbuild
index 1c8dd0f5cd5d..27cbc0267b9c 100644
--- a/arch/mn10300/include/asm/Kbuild
+++ b/arch/mn10300/include/asm/Kbuild
@@ -5,7 +5,6 @@ generic-y += cputime.h
 generic-y += exec.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += preempt.h
 generic-y += sections.h
 generic-y += trace_clock.h
diff --git a/arch/nios2/include/asm/Kbuild b/arch/nios2/include/asm/Kbuild
index d63330e88379..e22478929719 100644
--- a/arch/nios2/include/asm/Kbuild
+++ b/arch/nios2/include/asm/Kbuild
@@ -30,7 +30,6 @@ generic-y += kmap_types.h
 generic-y += kvm_para.h
 generic-y += local.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += module.h
 generic-y += msgbuf.h
diff --git a/arch/openrisc/include/asm/Kbuild b/arch/openrisc/include/asm/Kbuild
index 2832f031fb11..2a2e39b8109a 100644
--- a/arch/openrisc/include/asm/Kbuild
+++ b/arch/openrisc/include/asm/Kbuild
@@ -36,7 +36,6 @@ generic-y += kmap_types.h
 generic-y += kvm_para.h
 generic-y += local.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += module.h
 generic-y += msgbuf.h
diff --git a/arch/parisc/include/asm/Kbuild b/arch/parisc/include/asm/Kbuild
index f9b3a81aefcd..12b341d04f88 100644
--- a/arch/parisc/include/asm/Kbuild
+++ b/arch/parisc/include/asm/Kbuild
@@ -15,7 +15,6 @@ generic-y += kvm_para.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mutex.h
 generic-y += param.h
 generic-y += percpu.h
diff --git a/arch/powerpc/include/asm/mm-arch-hooks.h b/arch/powerpc/include/asm/mm-arch-hooks.h
deleted file mode 100644
index f2a2da895897..000000000000
--- a/arch/powerpc/include/asm/mm-arch-hooks.h
+++ /dev/null
@@ -1,28 +0,0 @@
-/*
- * Architecture specific mm hooks
- *
- * Copyright (C) 2015, IBM Corporation
- * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#ifndef _ASM_POWERPC_MM_ARCH_HOOKS_H
-#define _ASM_POWERPC_MM_ARCH_HOOKS_H
-
-static inline void arch_remap(struct mm_struct *mm,
-			      unsigned long old_start, unsigned long old_end,
-			      unsigned long new_start, unsigned long new_end)
-{
-	/*
-	 * mremap() doesn't allow moving multiple vmas so we can limit the
-	 * check to old_start == vdso_base.
-	 */
-	if (old_start == mm->context.vdso_base)
-		mm->context.vdso_base = new_start;
-}
-#define arch_remap arch_remap
-
-#endif /* _ASM_POWERPC_MM_ARCH_HOOKS_H */
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c
index 9ee3fd65c6e9..431bdf7ec68e 100644
--- a/arch/powerpc/kernel/vdso.c
+++ b/arch/powerpc/kernel/vdso.c
@@ -143,6 +143,31 @@ struct lib64_elfinfo
 	unsigned long	text;
 };
 
+static int vdso_mremap(const struct vm_special_mapping *sm,
+		struct vm_area_struct *new_vma)
+{
+	unsigned long new_size = new_vma->vm_end - new_vma->vm_start;
+	unsigned long vdso_pages;
+
+	if (is_32bit_task())
+		vdso_pages = vdso32_pages;
+#ifdef CONFIG_PPC64
+	else
+		vdso_pages = vdso64_pages;
+#endif
+
+	/* Do not allow partial remap, +1 is for vDSO data page */
+	if (new_size != (vdso_pages + 1) << PAGE_SHIFT)
+		return -EINVAL;
+
+	if (WARN_ON_ONCE(current->mm != new_vma->vm_mm))
+		return -EFAULT;
+
+	current->mm->context.vdso_base = new_vma->vm_start;
+
+	return 0;
+}
+
 static int map_vdso(struct vm_special_mapping *vsm, unsigned long vdso_pages,
 		unsigned long vdso_base)
 {
diff --git a/arch/powerpc/kernel/vdso_common.c b/arch/powerpc/kernel/vdso_common.c
index 047f6b8b230f..11fdf3e8acc7 100644
--- a/arch/powerpc/kernel/vdso_common.c
+++ b/arch/powerpc/kernel/vdso_common.c
@@ -225,6 +225,7 @@ static __init void init_vdso_pagelist(void)
 
 	vdso_mapping.pages = vdso_pagelist;
 	vdso_mapping.name = "[vdso]";
+	vdso_mapping.mremap = vdso_mremap;
 }
 
 #undef find_section
diff --git a/arch/s390/include/asm/Kbuild b/arch/s390/include/asm/Kbuild
index 20f196b82a6e..c1ef8252cc20 100644
--- a/arch/s390/include/asm/Kbuild
+++ b/arch/s390/include/asm/Kbuild
@@ -4,7 +4,6 @@ generic-y += clkdev.h
 generic-y += export.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += preempt.h
 generic-y += trace_clock.h
 generic-y += word-at-a-time.h
diff --git a/arch/score/include/asm/Kbuild b/arch/score/include/asm/Kbuild
index a05218ff3fe4..ff19975beb33 100644
--- a/arch/score/include/asm/Kbuild
+++ b/arch/score/include/asm/Kbuild
@@ -7,7 +7,6 @@ generic-y += clkdev.h
 generic-y += cputime.h
 generic-y += irq_work.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += preempt.h
 generic-y += sections.h
 generic-y += trace_clock.h
diff --git a/arch/sh/include/asm/Kbuild b/arch/sh/include/asm/Kbuild
index 751c3373a92c..7d1fb2c7fcba 100644
--- a/arch/sh/include/asm/Kbuild
+++ b/arch/sh/include/asm/Kbuild
@@ -17,7 +17,6 @@ generic-y += kvm_para.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += msgbuf.h
 generic-y += param.h
diff --git a/arch/sparc/include/asm/Kbuild b/arch/sparc/include/asm/Kbuild
index cfc918067f80..0867d5ab7f87 100644
--- a/arch/sparc/include/asm/Kbuild
+++ b/arch/sparc/include/asm/Kbuild
@@ -13,7 +13,6 @@ generic-y += linkage.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += module.h
 generic-y += mutex.h
 generic-y += preempt.h
diff --git a/arch/tile/include/asm/Kbuild b/arch/tile/include/asm/Kbuild
index ba35c41c71ff..40d22b4a01f9 100644
--- a/arch/tile/include/asm/Kbuild
+++ b/arch/tile/include/asm/Kbuild
@@ -19,7 +19,6 @@ generic-y += irq_regs.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += msgbuf.h
 generic-y += mutex.h
 generic-y += param.h
diff --git a/arch/um/include/asm/Kbuild b/arch/um/include/asm/Kbuild
index 904f3ebf4220..33c1d3e0caad 100644
--- a/arch/um/include/asm/Kbuild
+++ b/arch/um/include/asm/Kbuild
@@ -16,7 +16,6 @@ generic-y += irq_regs.h
 generic-y += irq_work.h
 generic-y += kdebug.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mutex.h
 generic-y += param.h
 generic-y += pci.h
diff --git a/arch/unicore32/include/asm/Kbuild b/arch/unicore32/include/asm/Kbuild
index 256c45b3ae34..932070cd754a 100644
--- a/arch/unicore32/include/asm/Kbuild
+++ b/arch/unicore32/include/asm/Kbuild
@@ -26,7 +26,6 @@ generic-y += kdebug.h
 generic-y += kmap_types.h
 generic-y += local.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += mman.h
 generic-y += module.h
 generic-y += msgbuf.h
diff --git a/arch/x86/include/asm/Kbuild b/arch/x86/include/asm/Kbuild
index 2cfed174e3c9..51b3d95f05e9 100644
--- a/arch/x86/include/asm/Kbuild
+++ b/arch/x86/include/asm/Kbuild
@@ -15,4 +15,3 @@ generic-y += cputime.h
 generic-y += dma-contiguous.h
 generic-y += early_ioremap.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
diff --git a/arch/xtensa/include/asm/Kbuild b/arch/xtensa/include/asm/Kbuild
index 28cf4c5d65ef..bdade9995e36 100644
--- a/arch/xtensa/include/asm/Kbuild
+++ b/arch/xtensa/include/asm/Kbuild
@@ -18,7 +18,6 @@ generic-y += linkage.h
 generic-y += local.h
 generic-y += local64.h
 generic-y += mcs_spinlock.h
-generic-y += mm-arch-hooks.h
 generic-y += percpu.h
 generic-y += preempt.h
 generic-y += resource.h
diff --git a/include/asm-generic/mm-arch-hooks.h b/include/asm-generic/mm-arch-hooks.h
deleted file mode 100644
index 5ff0e5193f85..000000000000
--- a/include/asm-generic/mm-arch-hooks.h
+++ /dev/null
@@ -1,16 +0,0 @@
-/*
- * Architecture specific mm hooks
- */
-
-#ifndef _ASM_GENERIC_MM_ARCH_HOOKS_H
-#define _ASM_GENERIC_MM_ARCH_HOOKS_H
-
-/*
- * This file should be included through arch/../include/asm/Kbuild for
- * the architecture which doesn't need specific mm hooks.
- *
- * In that case, the generic hooks defined in include/linux/mm-arch-hooks.h
- * are used.
- */
-
-#endif /* _ASM_GENERIC_MM_ARCH_HOOKS_H */
diff --git a/include/linux/mm-arch-hooks.h b/include/linux/mm-arch-hooks.h
deleted file mode 100644
index 4efc3f56e6df..000000000000
--- a/include/linux/mm-arch-hooks.h
+++ /dev/null
@@ -1,25 +0,0 @@
-/*
- * Generic mm no-op hooks.
- *
- * Copyright (C) 2015, IBM Corporation
- * Author: Laurent Dufour <ldufour@linux.vnet.ibm.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-#ifndef _LINUX_MM_ARCH_HOOKS_H
-#define _LINUX_MM_ARCH_HOOKS_H
-
-#include <asm/mm-arch-hooks.h>
-
-#ifndef arch_remap
-static inline void arch_remap(struct mm_struct *mm,
-			      unsigned long old_start, unsigned long old_end,
-			      unsigned long new_start, unsigned long new_end)
-{
-}
-#define arch_remap arch_remap
-#endif
-
-#endif /* _LINUX_MM_ARCH_HOOKS_H */
diff --git a/mm/mremap.c b/mm/mremap.c
index da22ad2a5678..5f1504c6cc77 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -21,7 +21,6 @@
 #include <linux/syscalls.h>
 #include <linux/mmu_notifier.h>
 #include <linux/uaccess.h>
-#include <linux/mm-arch-hooks.h>
 
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>
@@ -292,9 +291,6 @@ static unsigned long move_vma(struct vm_area_struct *vma,
 		old_len = new_len;
 		old_addr = new_addr;
 		new_addr = err;
-	} else {
-		arch_remap(mm, old_addr, old_addr + old_len,
-			   new_addr, new_addr + new_len);
 	}
 
 	/* Conceal VM_ACCOUNT so old reservation is not undone */
-- 
2.10.0

Re: [PATCH 0/7] powerpc/mm: refactor vDSO mapping code

[Dmitry Safonov]

2016-10-25 18:50 GMT+03:00 Dmitry Safonov <dsafonov@virtuozzo.com>:
> Cleanup patches for vDSO on powerpc.
> Originally, I wanted to add vDSO remapping on arm/aarch64 and
> I decided to cleanup that part on powerpc.
> I've add a hook for vm_ops for vDSO just like I did for x86.
> Other changes - reduce exhaustive code duplication.
> No visible to userspace changes expected.
>
> Tested on qemu with buildroot rootfs.
>
> Dmitry Safonov (7):
>   powerpc/vdso: unify return paths in setup_additional_pages
>   powerpc/vdso: remove unused params in vdso_do_func_patch{32,64}
>   powerpc/vdso: separate common code in vdso_common
>   powerpc/vdso: introduce init_vdso{32,64}_pagelist
>   powerpc/vdso: split map_vdso from arch_setup_additional_pages
>   powerpc/vdso: switch from legacy_special_mapping_vmops
>   mm: kill arch_mremap

Ignore this version, please - I've just sent v3 with some new fixes.