linux-kernel - [tip: timers/vdso] x86/vdso: Access timens vdso data without vvar.h

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Message-ID: <173054822091.3137.16845283982212981168.tip-bot2@tip-bot2>
Date: Sat, 02 Nov 2024 11:50:20 -0000
From:
 tip-bot2 for Thomas Weißschuh <tip-bot2@...utronix.de>
To: linux-tip-commits@...r.kernel.org
Cc: thomas.weissschuh@...utronix.de, Thomas Gleixner <tglx@...utronix.de>,
 x86@...nel.org, linux-kernel@...r.kernel.org
Subject: [tip: timers/vdso] x86/vdso: Access timens vdso data without vvar.h

The following commit has been merged into the timers/vdso branch of tip:

Commit-ID:     59b7761638a3f299750c04f431f2b4e1bea9465c
Gitweb:        https://git.kernel.org/tip/59b7761638a3f299750c04f431f2b4e1bea9465c
Author:        Thomas Weißschuh <thomas.weissschuh@...utronix.de>
AuthorDate:    Thu, 10 Oct 2024 09:01:17 +02:00
Committer:     Thomas Gleixner <tglx@...utronix.de>
CommitterDate: Sat, 02 Nov 2024 12:37:34 +01:00

x86/vdso: Access timens vdso data without vvar.h

The vdso_data is at the start of the timens page.
Make use of this invariant to remove the usage of vvar.h.
This also matches the logic for the pvclock and hvclock pages.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@...utronix.de>
Signed-off-by: Thomas Gleixner <tglx@...utronix.de>
Link: https://lore.kernel.org/all/20241010-vdso-generic-base-v1-15-b64f0842d512@linutronix.de

---
 arch/x86/entry/vdso/vdso-layout.lds.S    | 6 ------
 arch/x86/include/asm/vdso/getrandom.h    | 2 +-
 arch/x86/include/asm/vdso/gettimeofday.h | 6 ++++--
 3 files changed, 5 insertions(+), 9 deletions(-)

diff --git a/arch/x86/entry/vdso/vdso-layout.lds.S b/arch/x86/entry/vdso/vdso-layout.lds.S
index bafa73f..51c0cc0 100644
--- a/arch/x86/entry/vdso/vdso-layout.lds.S
+++ b/arch/x86/entry/vdso/vdso-layout.lds.S
@@ -28,12 +28,6 @@ SECTIONS
 	hvclock_page = vvar_start + 2 * PAGE_SIZE;
 	timens_page  = vvar_start + 3 * PAGE_SIZE;
 
-#undef _ASM_X86_VVAR_H
-	/* Place all vvars in timens too at the offsets in asm/vvar.h. */
-#define EMIT_VVAR(name, offset) timens_ ## name = timens_page + offset;
-#include <asm/vvar.h>
-#undef EMIT_VVAR
-
 	. = SIZEOF_HEADERS;
 
 	.hash		: { *(.hash) }			:text
diff --git a/arch/x86/include/asm/vdso/getrandom.h b/arch/x86/include/asm/vdso/getrandom.h
index ecdcdbc..d0713c8 100644
--- a/arch/x86/include/asm/vdso/getrandom.h
+++ b/arch/x86/include/asm/vdso/getrandom.h
@@ -33,7 +33,7 @@ static __always_inline ssize_t getrandom_syscall(void *buffer, size_t len, unsig
 static __always_inline const struct vdso_rng_data *__arch_get_vdso_rng_data(void)
 {
 	if (IS_ENABLED(CONFIG_TIME_NS) && __arch_get_vdso_data()->clock_mode == VDSO_CLOCKMODE_TIMENS)
-		return (void *)&__vdso_rng_data + ((void *)&__timens_vdso_data - (void *)__arch_get_vdso_data());
+		return (void *)&__vdso_rng_data + ((void *)&timens_page - (void *)__arch_get_vdso_data());
 	return &__vdso_rng_data;
 }
 
diff --git a/arch/x86/include/asm/vdso/gettimeofday.h b/arch/x86/include/asm/vdso/gettimeofday.h
index b2d2df0..1e61161 100644
--- a/arch/x86/include/asm/vdso/gettimeofday.h
+++ b/arch/x86/include/asm/vdso/gettimeofday.h
@@ -21,7 +21,9 @@
 #include <clocksource/hyperv_timer.h>
 
 #define __vdso_data (VVAR(_vdso_data))
-#define __timens_vdso_data (TIMENS(_vdso_data))
+
+extern struct vdso_data timens_page
+	__attribute__((visibility("hidden")));
 
 #define VDSO_HAS_TIME 1
 
@@ -61,7 +63,7 @@ extern struct ms_hyperv_tsc_page hvclock_page
 static __always_inline
 const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd)
 {
-	return __timens_vdso_data;
+	return &timens_page;
 }
 #endif