Merge tag 'timers-vdso-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull VDSO infrastructure updates from Thomas Gleixner:

 - Consolidate the VDSO storage

   The VDSO data storage and data layout has been largely architecture
   specific for historical reasons. That increases the maintenance
   effort and causes inconsistencies over and over.

   There is no real technical reason for architecture specific layouts
   and implementations. The architecture specific details can easily be
   integrated into a generic layout, which also reduces the amount of
   duplicated code for managing the mappings.

   Convert all architectures over to a unified layout and common mapping
   infrastructure. This splits the VDSO data layout into subsystem
   specific blocks, timekeeping, random and architecture parts, which
   provides a better structure and allows to improve and update the
   functionalities without conflict and interaction.

 - Rework the timekeeping data storage

   The current implementation is designed for exposing system
   timekeeping accessors, which was good enough at the time when it was
   designed.

   PTP and Time Sensitive Networking (TSN) change that as there are
   requirements to expose independent PTP clocks, which are not related
   to system timekeeping.

   Replace the monolithic data storage by a structured layout, which
   allows to add support for independent PTP clocks on top while reusing
   both the data structures and the time accessor implementations.

* tag 'timers-vdso-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (55 commits)
  sparc/vdso: Always reject undefined references during linking
  x86/vdso: Always reject undefined references during linking
  vdso: Rework struct vdso_time_data and introduce struct vdso_clock
  vdso: Move architecture related data before basetime data
  powerpc/vdso: Prepare introduction of struct vdso_clock
  arm64/vdso: Prepare introduction of struct vdso_clock
  x86/vdso: Prepare introduction of struct vdso_clock
  time/namespace: Prepare introduction of struct vdso_clock
  vdso/namespace: Rename timens_setup_vdso_data() to reflect new vdso_clock struct
  vdso/vsyscall: Prepare introduction of struct vdso_clock
  vdso/gettimeofday: Prepare helper functions for introduction of struct vdso_clock
  vdso/gettimeofday: Prepare do_coarse_timens() for introduction of struct vdso_clock
  vdso/gettimeofday: Prepare do_coarse() for introduction of struct vdso_clock
  vdso/gettimeofday: Prepare do_hres_timens() for introduction of struct vdso_clock
  vdso/gettimeofday: Prepare do_hres() for introduction of struct vdso_clock
  vdso/gettimeofday: Prepare introduction of struct vdso_clock
  vdso/helpers: Prepare introduction of struct vdso_clock
  vdso/datapage: Define vdso_clock to prepare for multiple PTP clocks
  vdso: Make vdso_time_data cacheline aligned
  arm64: Make asm/cache.h compatible with vDSO
  ...

3 files changed, 15 insertions, 27 deletions

diff --git a/arch/mips/include/asm/vdso/gettimeofday.h b/arch/mips/include/asm/vdso/gettimeofday.h
index 44a45f3fa4b0..fd32baa30e17 100644
--- a/arch/mips/include/asm/vdso/gettimeofday.h
+++ b/arch/mips/include/asm/vdso/gettimeofday.h
@@ -167,7 +167,7 @@ static __always_inline u64 read_r4k_count(void)
 
 #ifdef CONFIG_CLKSRC_MIPS_GIC
 
-static __always_inline u64 read_gic_count(const struct vdso_data *data)
+static __always_inline u64 read_gic_count(const struct vdso_time_data *data)
 {
 	void __iomem *gic = get_gic(data);
 	u32 hi, hi2, lo;
@@ -184,7 +184,7 @@ static __always_inline u64 read_gic_count(const struct vdso_data *data)
 #endif
 
 static __always_inline u64 __arch_get_hw_counter(s32 clock_mode,
-						 const struct vdso_data *vd)
+						 const struct vdso_time_data *vd)
 {
 #ifdef CONFIG_CSRC_R4K
 	if (clock_mode == VDSO_CLOCKMODE_R4K)
@@ -209,10 +209,11 @@ static inline bool mips_vdso_hres_capable(void)
 }
 #define __arch_vdso_hres_capable mips_vdso_hres_capable
 
-static __always_inline const struct vdso_data *__arch_get_vdso_data(void)
+static __always_inline const struct vdso_time_data *__arch_get_vdso_u_time_data(void)
 {
-	return get_vdso_data();
+	return get_vdso_time_data();
 }
+#define __arch_get_vdso_u_time_data __arch_get_vdso_u_time_data
 
 #endif /* !__ASSEMBLY__ */
 
diff --git a/arch/mips/include/asm/vdso/vdso.h b/arch/mips/include/asm/vdso/vdso.h
index 6cd88191fefa..acd0efcd3d93 100644
--- a/arch/mips/include/asm/vdso/vdso.h
+++ b/arch/mips/include/asm/vdso/vdso.h
@@ -5,16 +5,18 @@
  */
 
 #include <asm/sgidefs.h>
+#include <vdso/page.h>
+
+#define __VDSO_PAGES 4
 
 #ifndef __ASSEMBLY__
 
 #include <asm/asm.h>
-#include <asm/page.h>
 #include <asm/vdso.h>
 
-static inline unsigned long get_vdso_base(void)
+static inline const struct vdso_time_data *get_vdso_time_data(void)
 {
-	unsigned long addr;
+	const struct vdso_time_data *addr;
 
 	/*
 	 * We can't use cpu_has_mips_r6 since it needs the cpu_data[]
@@ -27,7 +29,7 @@ static inline unsigned long get_vdso_base(void)
 	 * We can't use addiupc because there is no label-label
 	 * support for the addiupc reloc
 	 */
-	__asm__("lapc	%0, _start			\n"
+	__asm__("lapc	%0, vdso_u_time_data		\n"
 		: "=r" (addr) : :);
 #else
 	/*
@@ -46,7 +48,7 @@ static inline unsigned long get_vdso_base(void)
 	"	.set noreorder				\n"
 	"	bal	1f				\n"
 	"	 nop					\n"
-	"	.word	_start - .			\n"
+	"	.word	vdso_u_time_data - .		\n"
 	"1:	lw	%0, 0($31)			\n"
 	"	" STR(PTR_ADDU) " %0, $31, %0		\n"
 	"	.set pop				\n"
@@ -58,14 +60,9 @@ static inline unsigned long get_vdso_base(void)
 	return addr;
 }
 
-static inline const struct vdso_data *get_vdso_data(void)
-{
-	return (const struct vdso_data *)(get_vdso_base() - PAGE_SIZE);
-}
-
 #ifdef CONFIG_CLKSRC_MIPS_GIC
 
-static inline void __iomem *get_gic(const struct vdso_data *data)
+static inline void __iomem *get_gic(const struct vdso_time_data *data)
 {
 	return (void __iomem *)((unsigned long)data & PAGE_MASK) - PAGE_SIZE;
 }
diff --git a/arch/mips/include/asm/vdso/vsyscall.h b/arch/mips/include/asm/vdso/vsyscall.h
index a4582870aaea..2b1debb62dee 100644
--- a/arch/mips/include/asm/vdso/vsyscall.h
+++ b/arch/mips/include/asm/vdso/vsyscall.h
@@ -2,22 +2,12 @@
 #ifndef __ASM_VDSO_VSYSCALL_H
 #define __ASM_VDSO_VSYSCALL_H
 
+#include <asm/page.h>
+
 #ifndef __ASSEMBLY__
 
 #include <vdso/datapage.h>
 
-extern struct vdso_data *vdso_data;
-
-/*
- * Update the vDSO data page to keep in sync with kernel timekeeping.
- */
-static __always_inline
-struct vdso_data *__mips_get_k_vdso_data(void)
-{
-	return vdso_data;
-}
-#define __arch_get_k_vdso_data __mips_get_k_vdso_data
-
 /* The asm-generic header needs to be included after the definitions above */
 #include <asm-generic/vdso/vsyscall.h>