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From: Vincenzo Frascino <vincenzo.frascino@arm.com>
To: linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org,
	linux-kselftest@vger.kernel.org
Cc: Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will.deacon@arm.com>, Arnd Bergmann <arnd@arndb.de>,
	Russell King <linux@armlinux.org.uk>,
	Ralf Baechle <ralf@linux-mips.org>,
	Paul Burton <paul.burton@mips.com>,
	Daniel Lezcano <daniel.lezcano@linaro.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Mark Salyzyn <salyzyn@android.com>,
	Peter Collingbourne <pcc@google.com>,
	Shuah Khan <shuah@kernel.org>,
	Dmitry Safonov <0x7f454c46@gmail.com>,
	Rasmus Villemoes <linux@rasmusvillemoes.dk>,
	Huw Davies <huw@codeweavers.com>,
	Shijith Thotton <sthotton@marvell.com>,
	Andre Przywara <andre.przywara@arm.com>
Subject: [PATCH v7 11/25] arm64: Refactor vDSO code
Date: Fri, 21 Jun 2019 10:52:38 +0100
Message-ID: <20190621095252.32307-12-vincenzo.frascino@arm.com> (raw)
In-Reply-To: <20190621095252.32307-1-vincenzo.frascino@arm.com>

Most of the code for initializing the vDSOs in arm64 and compat will
be in common, hence a refactor of the current code is required to avoid
duplication and simplify maintainability.

Refactor vdso.c to simplify the implementation of arm64 vDSO compat
(which will be pushed with a future patch).

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Tested-by: Shijith Thotton <sthotton@marvell.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
---
 arch/arm64/kernel/vdso.c | 215 ++++++++++++++++++++++++++-------------
 1 file changed, 144 insertions(+), 71 deletions(-)

diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c
index 23c38303a52a..aa1fb25a9fe4 100644
--- a/arch/arm64/kernel/vdso.c
+++ b/arch/arm64/kernel/vdso.c
@@ -40,7 +40,31 @@
 #include <asm/vdso.h>
 
 extern char vdso_start[], vdso_end[];
-static unsigned long vdso_pages __ro_after_init;
+
+/* vdso_lookup arch_index */
+enum arch_vdso_type {
+	ARM64_VDSO = 0,
+};
+#define VDSO_TYPES		(ARM64_VDSO + 1)
+
+struct __vdso_abi {
+	const char *name;
+	const char *vdso_code_start;
+	const char *vdso_code_end;
+	unsigned long vdso_pages;
+	/* Data Mapping */
+	struct vm_special_mapping *dm;
+	/* Code Mapping */
+	struct vm_special_mapping *cm;
+};
+
+static struct __vdso_abi vdso_lookup[VDSO_TYPES] __ro_after_init = {
+	{
+		.name = "vdso",
+		.vdso_code_start = vdso_start,
+		.vdso_code_end = vdso_end,
+	},
+};
 
 /*
  * The vDSO data page.
@@ -51,10 +75,110 @@ static union {
 } vdso_data_store __page_aligned_data;
 struct vdso_data *vdso_data = vdso_data_store.data;
 
+static int __vdso_remap(enum arch_vdso_type arch_index,
+			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_size = vdso_lookup[arch_index].vdso_code_end -
+				  vdso_lookup[arch_index].vdso_code_start;
+
+	if (vdso_size != new_size)
+		return -EINVAL;
+
+	current->mm->context.vdso = (void *)new_vma->vm_start;
+
+	return 0;
+}
+
+static int __vdso_init(enum arch_vdso_type arch_index)
+{
+	int i;
+	struct page **vdso_pagelist;
+	unsigned long pfn;
+
+	if (memcmp(vdso_lookup[arch_index].vdso_code_start, "\177ELF", 4)) {
+		pr_err("vDSO is not a valid ELF object!\n");
+		return -EINVAL;
+	}
+
+	vdso_lookup[arch_index].vdso_pages = (
+			vdso_lookup[arch_index].vdso_code_end -
+			vdso_lookup[arch_index].vdso_code_start) >>
+			PAGE_SHIFT;
+
+	/* Allocate the vDSO pagelist, plus a page for the data. */
+	vdso_pagelist = kcalloc(vdso_lookup[arch_index].vdso_pages + 1,
+				sizeof(struct page *),
+				GFP_KERNEL);
+	if (vdso_pagelist == NULL)
+		return -ENOMEM;
+
+	/* Grab the vDSO data page. */
+	vdso_pagelist[0] = phys_to_page(__pa_symbol(vdso_data));
+
+
+	/* Grab the vDSO code pages. */
+	pfn = sym_to_pfn(vdso_lookup[arch_index].vdso_code_start);
+
+	for (i = 0; i < vdso_lookup[arch_index].vdso_pages; i++)
+		vdso_pagelist[i + 1] = pfn_to_page(pfn + i);
+
+	vdso_lookup[arch_index].dm->pages = &vdso_pagelist[0];
+	vdso_lookup[arch_index].cm->pages = &vdso_pagelist[1];
+
+	return 0;
+}
+
+static int __setup_additional_pages(enum arch_vdso_type arch_index,
+				    struct mm_struct *mm,
+				    struct linux_binprm *bprm,
+				    int uses_interp)
+{
+	unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
+	void *ret;
+
+	vdso_text_len = vdso_lookup[arch_index].vdso_pages << PAGE_SHIFT;
+	/* Be sure to map the data page */
+	vdso_mapping_len = vdso_text_len + PAGE_SIZE;
+
+	vdso_base = get_unmapped_area(NULL, 0, vdso_mapping_len, 0, 0);
+	if (IS_ERR_VALUE(vdso_base)) {
+		ret = ERR_PTR(vdso_base);
+		goto up_fail;
+	}
+
+	ret = _install_special_mapping(mm, vdso_base, PAGE_SIZE,
+				       VM_READ|VM_MAYREAD,
+				       vdso_lookup[arch_index].dm);
+	if (IS_ERR(ret))
+		goto up_fail;
+
+	vdso_base += PAGE_SIZE;
+	mm->context.vdso = (void *)vdso_base;
+	ret = _install_special_mapping(mm, vdso_base, vdso_text_len,
+				       VM_READ|VM_EXEC|
+				       VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
+				       vdso_lookup[arch_index].cm);
+	if (IS_ERR(ret))
+		goto up_fail;
+
+	return 0;
+
+up_fail:
+	mm->context.vdso = NULL;
+	return PTR_ERR(ret);
+}
+
 #ifdef CONFIG_COMPAT
 /*
  * Create and map the vectors page for AArch32 tasks.
  */
+/*
+ * aarch32_vdso_pages:
+ * 0 - kuser helpers
+ * 1 - sigreturn code
+ */
 #define C_VECTORS	0
 #define C_SIGPAGE	1
 #define C_PAGES		(C_SIGPAGE + 1)
@@ -183,18 +307,18 @@ int aarch32_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 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_size = vdso_end - vdso_start;
-
-	if (vdso_size != new_size)
-		return -EINVAL;
-
-	current->mm->context.vdso = (void *)new_vma->vm_start;
-
-	return 0;
+	return __vdso_remap(ARM64_VDSO, sm, new_vma);
 }
 
-static struct vm_special_mapping vdso_spec[2] __ro_after_init = {
+/*
+ * aarch64_vdso_pages:
+ * 0 - vvar
+ * 1 - vdso
+ */
+#define A_VVAR		0
+#define A_VDSO		1
+#define A_PAGES		(A_VDSO + 1)
+static struct vm_special_mapping vdso_spec[A_PAGES] __ro_after_init = {
 	{
 		.name	= "[vvar]",
 	},
@@ -206,37 +330,10 @@ static struct vm_special_mapping vdso_spec[2] __ro_after_init = {
 
 static int __init vdso_init(void)
 {
-	int i;
-	struct page **vdso_pagelist;
-	unsigned long pfn;
-
-	if (memcmp(vdso_start, "\177ELF", 4)) {
-		pr_err("vDSO is not a valid ELF object!\n");
-		return -EINVAL;
-	}
-
-	vdso_pages = (vdso_end - vdso_start) >> PAGE_SHIFT;
-
-	/* Allocate the vDSO pagelist, plus a page for the data. */
-	vdso_pagelist = kcalloc(vdso_pages + 1, sizeof(struct page *),
-				GFP_KERNEL);
-	if (vdso_pagelist == NULL)
-		return -ENOMEM;
-
-	/* Grab the vDSO data page. */
-	vdso_pagelist[0] = phys_to_page(__pa_symbol(vdso_data));
-
+	vdso_lookup[ARM64_VDSO].dm = &vdso_spec[A_VVAR];
+	vdso_lookup[ARM64_VDSO].cm = &vdso_spec[A_VDSO];
 
-	/* Grab the vDSO code pages. */
-	pfn = sym_to_pfn(vdso_start);
-
-	for (i = 0; i < vdso_pages; i++)
-		vdso_pagelist[i + 1] = pfn_to_page(pfn + i);
-
-	vdso_spec[0].pages = &vdso_pagelist[0];
-	vdso_spec[1].pages = &vdso_pagelist[1];
-
-	return 0;
+	return __vdso_init(ARM64_VDSO);
 }
 arch_initcall(vdso_init);
 
@@ -244,41 +341,17 @@ int arch_setup_additional_pages(struct linux_binprm *bprm,
 				int uses_interp)
 {
 	struct mm_struct *mm = current->mm;
-	unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
-	void *ret;
-
-	vdso_text_len = vdso_pages << PAGE_SHIFT;
-	/* Be sure to map the data page */
-	vdso_mapping_len = vdso_text_len + PAGE_SIZE;
+	int ret;
 
 	if (down_write_killable(&mm->mmap_sem))
 		return -EINTR;
-	vdso_base = get_unmapped_area(NULL, 0, vdso_mapping_len, 0, 0);
-	if (IS_ERR_VALUE(vdso_base)) {
-		ret = ERR_PTR(vdso_base);
-		goto up_fail;
-	}
-	ret = _install_special_mapping(mm, vdso_base, PAGE_SIZE,
-				       VM_READ|VM_MAYREAD,
-				       &vdso_spec[0]);
-	if (IS_ERR(ret))
-		goto up_fail;
-
-	vdso_base += PAGE_SIZE;
-	mm->context.vdso = (void *)vdso_base;
-	ret = _install_special_mapping(mm, vdso_base, vdso_text_len,
-				       VM_READ|VM_EXEC|
-				       VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
-				       &vdso_spec[1]);
-	if (IS_ERR(ret))
-		goto up_fail;
 
+	ret = __setup_additional_pages(ARM64_VDSO,
+				       mm,
+				       bprm,
+				       uses_interp);
 
 	up_write(&mm->mmap_sem);
-	return 0;
 
-up_fail:
-	mm->context.vdso = NULL;
-	up_write(&mm->mmap_sem);
-	return PTR_ERR(ret);
+	return ret;
 }
-- 
2.21.0


  parent reply index

Thread overview: 108+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-06-21  9:52 [PATCH v7 00/25] Unify vDSOs across more architectures Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 01/25] kernel: Standardize vdso_datapage Vincenzo Frascino
2019-06-24 13:56   ` Catalin Marinas
2019-06-21  9:52 ` [PATCH v7 02/25] kernel: Define gettimeofday vdso common code Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 03/25] kernel: Unify update_vsyscall implementation Vincenzo Frascino
2019-06-21 10:49   ` Huw Davies
2019-06-21  9:52 ` [PATCH v7 04/25] arm64: Substitute gettimeofday with C implementation Vincenzo Frascino
2019-06-24 13:36   ` Will Deacon
2019-06-24 13:59     ` Vincenzo Frascino
2019-06-25 16:18     ` [PATCH 1/3] lib/vdso: Delay mask application in do_hres() Vincenzo Frascino
2019-06-25 16:18       ` [PATCH 2/3] arm64: Fix __arch_get_hw_counter() implementation Vincenzo Frascino
2019-06-25 16:18       ` [PATCH 3/3] arm64: compat: " Vincenzo Frascino
2019-06-25 17:02       ` [PATCH 1/3] lib/vdso: Delay mask application in do_hres() Thomas Gleixner
2019-06-25 18:27         ` Thomas Gleixner
2019-06-25 20:15           ` Andy Lutomirski
2019-06-25 22:24             ` Thomas Gleixner
2019-06-26  6:38         ` Thomas Gleixner
2019-06-26  9:25           ` Vincenzo Frascino
2019-06-26 10:02             ` lib/vdso: Make delta calculation work correctly Thomas Gleixner
2019-06-26 11:08               ` Vincenzo Frascino
2019-06-24 13:58   ` [PATCH v7 04/25] arm64: Substitute gettimeofday with C implementation Catalin Marinas
2019-06-25 15:33   ` Dave Martin
2019-06-26 13:27     ` Vincenzo Frascino
2019-06-26 16:14       ` Dave Martin
2019-06-26 19:01         ` Vincenzo Frascino
2019-06-27 10:01           ` Dave Martin
2019-06-27 10:57             ` Vincenzo Frascino
2019-06-27 11:27               ` Dave Martin
2019-06-27 11:59                 ` Vincenzo Frascino
2019-06-27 14:38                   ` Dave Martin
2019-06-27 15:34                     ` Vincenzo Frascino
2019-06-25 17:43   ` [PATCH] arm64: vdso: Fix compilation with clang < 8 Vincenzo Frascino
2019-06-26 11:36   ` [PATCH v2] arm64: vdso: Fix compilation with clang older then 8 Vincenzo Frascino
     [not found]   ` <CGME20190628130921eucas1p239935b0771032c331911eacc1a69dd2e@eucas1p2.samsung.com>
2019-06-28 13:09     ` [PATCH v7 04/25] arm64: Substitute gettimeofday with C implementation Marek Szyprowski
2019-06-28 14:32       ` Vincenzo Frascino
2019-06-28 16:50         ` Sylwester Nawrocki
2019-06-29  6:58           ` Vincenzo Frascino
2019-07-08 12:57             ` Sylwester Nawrocki
2019-07-08 13:09               ` Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 05/25] arm64: Build vDSO with -ffixed-x18 Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 06/25] arm64: compat: Add missing syscall numbers Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 07/25] arm64: compat: Expose signal related structures Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 08/25] arm64: compat: Generate asm offsets for signals Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 09/25] lib: vdso: Add compat support Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 10/25] arm64: compat: Add vDSO Vincenzo Frascino
2019-06-24 14:00   ` Catalin Marinas
2019-07-10  4:02   ` John Stultz
2019-07-10  6:12     ` Thomas Gleixner
2019-07-10  9:48       ` Vincenzo Frascino
2019-07-10  8:27     ` Will Deacon
2019-07-10  8:58       ` Thomas Gleixner
2019-07-10  9:12         ` Will Deacon
2019-07-10  9:47     ` Vincenzo Frascino
2019-07-10 13:41       ` Vincenzo Frascino
2019-07-10 13:04   ` [PATCH] arm64: vdso: Fix ABI regression in compat vdso Vincenzo Frascino
2019-07-10 13:25     ` Will Deacon
2019-07-10 13:42       ` Vincenzo Frascino
2019-07-10 14:01   ` [PATCH v2] " Vincenzo Frascino
2019-07-10 15:44     ` John Stultz
2019-07-10 15:53       ` Vincenzo Frascino
2019-07-11  9:45     ` Will Deacon
2019-07-11 10:34       ` Thomas Gleixner
2019-07-11 11:32         ` Will Deacon
2019-06-21  9:52 ` Vincenzo Frascino [this message]
2019-06-21  9:52 ` [PATCH v7 12/25] arm64: compat: vDSO setup for compat layer Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 13/25] arm64: elf: vDSO code page discovery Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 14/25] arm64: compat: Get sigreturn trampolines from vDSO Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 15/25] arm64: Add vDSO compat support Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 16/25] arm: Add support for generic vDSO Vincenzo Frascino
2019-12-04 13:51   ` [PATCH v7 16/25] arm: Add support for generic vDSO (causing crash) Guenter Roeck
2019-12-04 13:58     ` Vincenzo Frascino
2019-12-04 16:16       ` Guenter Roeck
2019-12-04 17:15         ` Vincenzo Frascino
2019-12-04 19:39           ` Guenter Roeck
2019-12-05  9:42           ` Philippe Mathieu-Daudé
2019-12-05 10:00             ` Vincenzo Frascino
2019-12-05 11:02               ` Arnd Bergmann
2019-12-05 14:56                 ` Philippe Mathieu-Daudé
2019-06-21  9:52 ` [PATCH v7 17/25] arm: Add clock_getres entry point Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 18/25] arm: Add clock_gettime64 " Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 19/25] mips: Add support for generic vDSO Vincenzo Frascino
2019-07-26  5:15   ` Paul Burton
2019-07-26 16:29     ` [PATCH 0/2] mips: vdso: Fix Makefile Vincenzo Frascino
2019-07-26 16:29       ` [PATCH 1/2] mips: vdso: Fix source path Vincenzo Frascino
2019-07-26 16:29       ` [PATCH 2/2] mips: vdso: Fix flip/flop vdso building bug Vincenzo Frascino
2019-07-28 22:20       ` [PATCH 0/2] mips: vdso: Fix Makefile Paul Burton
2019-06-21  9:52 ` [PATCH v7 20/25] mips: Add clock_getres entry point Vincenzo Frascino
2019-07-26  5:15   ` Paul Burton
2019-06-21  9:52 ` [PATCH v7 21/25] mips: Add clock_gettime64 " Vincenzo Frascino
2019-07-26  5:15   ` Paul Burton
2019-06-21  9:52 ` [PATCH v7 22/25] x86: Add support for generic vDSO Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 23/25] x86: Add clock_getres entry point Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 24/25] x86: Add clock_gettime64 " Vincenzo Frascino
2019-06-21  9:52 ` [PATCH v7 25/25] kselftest: Extend vDSO selftest Vincenzo Frascino
2019-06-24  0:34 ` [PATCH v7 00/25] Unify vDSOs across more architectures Thomas Gleixner
2019-06-24  1:15   ` Andy Lutomirski
2019-06-24  7:42     ` Thomas Gleixner
2019-06-24 13:21   ` Vincenzo Frascino
2019-06-24 14:18   ` Thomas Gleixner
2019-06-24 14:23     ` Russell King - ARM Linux admin
2019-06-24 14:49       ` Catalin Marinas
2019-06-24 16:20         ` Vincenzo Frascino
2019-10-25 11:42         ` Geert Uytterhoeven
2019-06-24 18:41   ` Paul Burton
2019-06-24 23:16     ` Vincenzo Frascino
2019-06-25 17:11       ` Paul Burton
2019-06-25 17:17         ` Vincenzo Frascino
2019-06-24 12:50 ` Andre Przywara

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