From: Vincenzo Frascino <vincenzo.frascino@arm.com>
To: linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org
Cc: Arnd Bergmann <arnd@arndb.de>,
Catalin Marinas <catalin.marinas@arm.com>,
Daniel Lezcano <daniel.lezcano@linaro.org>,
Will Deacon <will.deacon@arm.com>,
Russell King <linux@armlinux.org.uk>,
Ralf Baechle <ralf@linux-mips.org>,
Mark Salyzyn <salyzyn@android.com>,
Paul Burton <paul.burton@mips.com>,
Thomas Gleixner <tglx@linutronix.de>,
Peter Collingbourne <pcc@google.com>
Subject: [PATCH v2 18/28] arm64: Refactor vDSO code
Date: Thu, 29 Nov 2018 17:05:20 +0000 [thread overview]
Message-ID: <20181129170530.37789-19-vincenzo.frascino@arm.com> (raw)
In-Reply-To: <20181129170530.37789-1-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.
This patch refactors 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>
---
arch/arm64/kernel/vdso.c | 208 +++++++++++++++++++++++++--------------
1 file changed, 135 insertions(+), 73 deletions(-)
diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c
index 8903087cca4c..f8020db654db 100644
--- a/arch/arm64/kernel/vdso.c
+++ b/arch/arm64/kernel/vdso.c
@@ -40,7 +40,30 @@
#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,
+};
+
+struct __vdso_lookup_t {
+ 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_lookup_t vdso_lookup[2] __ro_after_init = {
+ {
+ .name = "vdso",
+ .vdso_code_start = vdso_start,
+ .vdso_code_end = vdso_end,
+ },
+};
/*
* The vDSO data page.
@@ -51,6 +74,106 @@ 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;
+ pr_info("%s: %ld pages (%ld code @ %p, %ld data @ %p)\n",
+ vdso_lookup[arch_index].name,
+ vdso_lookup[arch_index].vdso_pages + 1,
+ vdso_lookup[arch_index].vdso_pages,
+ vdso_lookup[arch_index].vdso_code_start, 1L, vdso_data);
+
+ /* 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.
@@ -61,7 +184,7 @@ struct vdso_data *vdso_data = &vdso_data_store.data;
* 1 - sigreturn code
*/
static struct page *aarch32_vdso_pages[2] __ro_after_init;
-static const struct vm_special_mapping aarch32_vdso_spec[2] = {
+static struct vm_special_mapping aarch32_vdso_spec[2] __ro_after_init = {
{
/* Must be named [vectors] for compatibility with arm. */
.name = "[vectors]",
@@ -201,15 +324,7 @@ 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 = {
@@ -224,39 +339,10 @@ 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;
+ vdso_lookup[ARM64_VDSO].dm = &vdso_spec[0];
+ vdso_lookup[ARM64_VDSO].cm = &vdso_spec[1];
- 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;
- pr_info("vdso: %ld pages (%ld code @ %p, %ld data @ %p)\n",
- vdso_pages + 1, vdso_pages, vdso_start, 1L, vdso_data);
-
- /* 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));
-
-
- /* 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);
@@ -264,43 +350,19 @@ 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;
}
#define VDSO_PRECISION_MASK ~(0xFF00ULL<<48)
--
2.19.2
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2018-11-29 17:25 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-29 17:05 [PATCH v2 00/28] Unify vDSOs across more architectures Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 01/28] kernel: Standardize vdso_datapage Vincenzo Frascino
2018-11-29 22:39 ` Thomas Gleixner
2018-12-11 13:22 ` Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 02/28] kernel: Add Monotonic boot time support Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 03/28] kernel: Add International Atomic Time support Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 04/28] kernel: Add masks support for Raw and NTP time Vincenzo Frascino
2018-11-29 22:41 ` Thomas Gleixner
2018-12-11 13:24 ` Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 05/28] kernel: Add clock_mode support Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 06/28] kernel: Define gettimeofday vdso common code Vincenzo Frascino
2018-11-29 20:42 ` Arnd Bergmann
2018-12-11 13:39 ` Vincenzo Frascino
2018-12-11 21:41 ` Arnd Bergmann
2018-12-13 9:46 ` Vincenzo Frascino
2018-11-29 22:11 ` Thomas Gleixner
2018-11-30 14:29 ` Arnd Bergmann
2018-12-11 14:02 ` Vincenzo Frascino
2018-12-07 17:53 ` Will Deacon
2019-02-08 17:35 ` Will Deacon
2019-02-08 19:28 ` Thomas Gleixner
2019-02-08 19:30 ` Thomas Gleixner
2019-02-13 17:04 ` Will Deacon
2019-02-13 19:35 ` Thomas Gleixner
2019-02-13 17:05 ` Will Deacon
2018-12-11 13:54 ` Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 07/28] arm64: Build vDSO with -ffixed-x18 Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 08/28] arm64: Substitute gettimeofday with C implementation Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 09/28] arm64: compat: Alloc separate pages for vectors and sigpage Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 10/28] arm64: compat: Split kuser32 Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 11/28] arm64: compat: Refactor aarch32_alloc_vdso_pages() Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 12/28] arm64: compat: Add KUSER_HELPERS config option Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 13/28] arm64: compat: Add missing syscall numbers Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 14/28] arm64: compat: Expose signal related structures Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 15/28] arm64: compat: Generate asm offsets for signals Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 16/28] lib: vdso: Add compat support Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 17/28] arm64: compat: Add vDSO Vincenzo Frascino
2018-11-29 17:05 ` Vincenzo Frascino [this message]
2018-11-29 17:05 ` [PATCH v2 19/28] arm64: compat: vDSO setup for compat layer Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 20/28] arm64: elf: vDSO code page discovery Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 21/28] arm64: compat: Get sigreturn trampolines from vDSO Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 22/28] arm64: Add vDSO compat support Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 23/28] arm64: Enable compat vDSO support Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 24/28] arm: Add support for generic vDSO Vincenzo Frascino
2018-12-10 22:13 ` Mark Salyzyn
2018-12-11 14:15 ` Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 25/28] mips: Introduce vdso_direct Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 26/28] clock: csrc-4k: Add support for vdso_direct Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 27/28] clock: gic-timer: " Vincenzo Frascino
2018-11-29 17:05 ` [PATCH v2 28/28] mips: Add support for generic vDSO Vincenzo Frascino
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20181129170530.37789-19-vincenzo.frascino@arm.com \
--to=vincenzo.frascino@arm.com \
--cc=arnd@arndb.de \
--cc=catalin.marinas@arm.com \
--cc=daniel.lezcano@linaro.org \
--cc=linux-arch@vger.kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux@armlinux.org.uk \
--cc=paul.burton@mips.com \
--cc=pcc@google.com \
--cc=ralf@linux-mips.org \
--cc=salyzyn@android.com \
--cc=tglx@linutronix.de \
--cc=will.deacon@arm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).