From 24640f233b466051ad3a5d2786d2951e43026c9d Mon Sep 17 00:00:00 2001 From: Vincenzo Frascino Date: Fri, 21 Jun 2019 10:52:46 +0100 Subject: [PATCH] mips: Add support for generic vDSO The mips vDSO library requires some adaptations to take advantage of the newly introduced generic vDSO library. Introduce the following changes: - Modification of vdso.c to be compliant with the common vdso datapage - Use of lib/vdso for gettimeofday Cc: Ralf Baechle Cc: Paul Burton Signed-off-by: Vincenzo Frascino [paul.burton@mips.com: Prepend $(src) to config-n32-o32-env.c path.] Signed-off-by: Paul Burton --- arch/mips/Kconfig | 2 + arch/mips/include/asm/vdso.h | 78 +---------- arch/mips/include/asm/vdso/gettimeofday.h | 151 ++++++++++++++++++++++ arch/mips/{ => include/asm}/vdso/vdso.h | 6 +- arch/mips/include/asm/vdso/vsyscall.h | 43 ++++++ arch/mips/kernel/vdso.c | 37 +----- arch/mips/vdso/Makefile | 33 ++++- arch/mips/vdso/config-n32-o32-env.c | 17 +++ arch/mips/vdso/elf.S | 2 +- arch/mips/vdso/sigreturn.S | 2 +- arch/mips/vdso/vgettimeofday.c | 40 ++++++ 11 files changed, 296 insertions(+), 115 deletions(-) create mode 100644 arch/mips/include/asm/vdso/gettimeofday.h rename arch/mips/{ => include/asm}/vdso/vdso.h (89%) create mode 100644 arch/mips/include/asm/vdso/vsyscall.h create mode 100644 arch/mips/vdso/config-n32-o32-env.c create mode 100644 arch/mips/vdso/vgettimeofday.c diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 947c75684897..99078c1b5273 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -22,6 +22,7 @@ config MIPS select GENERIC_CLOCKEVENTS select GENERIC_CMOS_UPDATE select GENERIC_CPU_AUTOPROBE + select GENERIC_GETTIMEOFDAY select GENERIC_IOMAP select GENERIC_IRQ_PROBE select GENERIC_IRQ_SHOW @@ -74,6 +75,7 @@ config MIPS select HAVE_STACKPROTECTOR select HAVE_SYSCALL_TRACEPOINTS select HAVE_VIRT_CPU_ACCOUNTING_GEN if 64BIT || !SMP + select HAVE_GENERIC_VDSO select IRQ_FORCED_THREADING select ISA if EISA select MODULES_USE_ELF_RELA if MODULES && 64BIT diff --git a/arch/mips/include/asm/vdso.h b/arch/mips/include/asm/vdso.h index a013fa4a3682..cc7b516129a8 100644 --- a/arch/mips/include/asm/vdso.h +++ b/arch/mips/include/asm/vdso.h @@ -8,6 +8,7 @@ #define __ASM_VDSO_H #include +#include #include @@ -49,84 +50,9 @@ extern struct mips_vdso_image vdso_image_o32; extern struct mips_vdso_image vdso_image_n32; #endif -/** - * union mips_vdso_data - Data provided by the kernel for the VDSO. - * @xtime_sec: Current real time (seconds part). - * @xtime_nsec: Current real time (nanoseconds part, shifted). - * @wall_to_mono_sec: Wall-to-monotonic offset (seconds part). - * @wall_to_mono_nsec: Wall-to-monotonic offset (nanoseconds part). - * @seq_count: Counter to synchronise updates (odd = updating). - * @cs_shift: Clocksource shift value. - * @clock_mode: Clocksource to use for time functions. - * @cs_mult: Clocksource multiplier value. - * @cs_cycle_last: Clock cycle value at last update. - * @cs_mask: Clocksource mask value. - * @tz_minuteswest: Minutes west of Greenwich (from timezone). - * @tz_dsttime: Type of DST correction (from timezone). - * - * This structure contains data needed by functions within the VDSO. It is - * populated by the kernel and mapped read-only into user memory. The time - * fields are mirrors of internal data from the timekeeping infrastructure. - * - * Note: Care should be taken when modifying as the layout must remain the same - * for both 64- and 32-bit (for 32-bit userland on 64-bit kernel). - */ union mips_vdso_data { - struct { - u64 xtime_sec; - u64 xtime_nsec; - u64 wall_to_mono_sec; - u64 wall_to_mono_nsec; - u32 seq_count; - u32 cs_shift; - u8 clock_mode; - u32 cs_mult; - u64 cs_cycle_last; - u64 cs_mask; - s32 tz_minuteswest; - s32 tz_dsttime; - }; - + struct vdso_data data[CS_BASES]; u8 page[PAGE_SIZE]; }; -static inline u32 vdso_data_read_begin(const union mips_vdso_data *data) -{ - u32 seq; - - while (true) { - seq = READ_ONCE(data->seq_count); - if (likely(!(seq & 1))) { - /* Paired with smp_wmb() in vdso_data_write_*(). */ - smp_rmb(); - return seq; - } - - cpu_relax(); - } -} - -static inline bool vdso_data_read_retry(const union mips_vdso_data *data, - u32 start_seq) -{ - /* Paired with smp_wmb() in vdso_data_write_*(). */ - smp_rmb(); - return unlikely(data->seq_count != start_seq); -} - -static inline void vdso_data_write_begin(union mips_vdso_data *data) -{ - ++data->seq_count; - - /* Ensure sequence update is written before other data page values. */ - smp_wmb(); -} - -static inline void vdso_data_write_end(union mips_vdso_data *data) -{ - /* Ensure data values are written before updating sequence again. */ - smp_wmb(); - ++data->seq_count; -} - #endif /* __ASM_VDSO_H */ diff --git a/arch/mips/include/asm/vdso/gettimeofday.h b/arch/mips/include/asm/vdso/gettimeofday.h new file mode 100644 index 000000000000..aa20865b288b --- /dev/null +++ b/arch/mips/include/asm/vdso/gettimeofday.h @@ -0,0 +1,151 @@ +/* + * Copyright (C) 2018 ARM Limited + * Copyright (C) 2015 Imagination Technologies + * Author: Alex Smith + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ +#ifndef __ASM_VDSO_GETTIMEOFDAY_H +#define __ASM_VDSO_GETTIMEOFDAY_H + +#ifndef __ASSEMBLY__ + +#include +#include + +#include +#include +#include +#include +#include + +#ifdef CONFIG_MIPS_CLOCK_VSYSCALL + +static __always_inline long gettimeofday_fallback( + struct __kernel_old_timeval *_tv, + struct timezone *_tz) +{ + register struct timezone *tz asm("a1") = _tz; + register struct __kernel_old_timeval *tv asm("a0") = _tv; + register long ret asm("v0"); + register long nr asm("v0") = __NR_gettimeofday; + register long error asm("a3"); + + asm volatile( + " syscall\n" + : "=r" (ret), "=r" (error) + : "r" (tv), "r" (tz), "r" (nr) + : "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13", + "$14", "$15", "$24", "$25", "hi", "lo", "memory"); + + return error ? -ret : ret; +} + +#else + +static __always_inline long gettimeofday_fallback( + struct __kernel_old_timeval *_tv, + struct timezone *_tz) +{ + return -1; +} + +#endif + +static __always_inline long clock_gettime_fallback( + clockid_t _clkid, + struct __kernel_timespec *_ts) +{ + register struct __kernel_timespec *ts asm("a1") = _ts; + register clockid_t clkid asm("a0") = _clkid; + register long ret asm("v0"); +#if _MIPS_SIM == _MIPS_SIM_ABI64 + register long nr asm("v0") = __NR_clock_gettime; +#else + register long nr asm("v0") = __NR_clock_gettime64; +#endif + register long error asm("a3"); + + asm volatile( + " syscall\n" + : "=r" (ret), "=r" (error) + : "r" (clkid), "r" (ts), "r" (nr) + : "$1", "$3", "$8", "$9", "$10", "$11", "$12", "$13", + "$14", "$15", "$24", "$25", "hi", "lo", "memory"); + + return error ? -ret : ret; +} + +#ifdef CONFIG_CSRC_R4K + +static __always_inline u64 read_r4k_count(void) +{ + unsigned int count; + + __asm__ __volatile__( + " .set push\n" + " .set mips32r2\n" + " rdhwr %0, $2\n" + " .set pop\n" + : "=r" (count)); + + return count; +} + +#endif + +#ifdef CONFIG_CLKSRC_MIPS_GIC + +static __always_inline u64 read_gic_count(const struct vdso_data *data) +{ + void __iomem *gic = get_gic(data); + u32 hi, hi2, lo; + + do { + hi = __raw_readl(gic + sizeof(lo)); + lo = __raw_readl(gic); + hi2 = __raw_readl(gic + sizeof(lo)); + } while (hi2 != hi); + + return (((u64)hi) << 32) + lo; +} + +#endif + +static __always_inline u64 __arch_get_hw_counter(s32 clock_mode) +{ +#ifdef CONFIG_CLKSRC_MIPS_GIC + const struct vdso_data *data = get_vdso_data(); +#endif + u64 cycle_now; + + switch (clock_mode) { +#ifdef CONFIG_CSRC_R4K + case VDSO_CLOCK_R4K: + cycle_now = read_r4k_count(); + break; +#endif +#ifdef CONFIG_CLKSRC_MIPS_GIC + case VDSO_CLOCK_GIC: + cycle_now = read_gic_count(data); + break; +#endif + default: + cycle_now = 0; + break; + } + + return cycle_now; +} + +static __always_inline const struct vdso_data *__arch_get_vdso_data(void) +{ + return get_vdso_data(); +} + +#endif /* !__ASSEMBLY__ */ + +#endif /* __ASM_VDSO_GETTIMEOFDAY_H */ diff --git a/arch/mips/vdso/vdso.h b/arch/mips/include/asm/vdso/vdso.h similarity index 89% rename from arch/mips/vdso/vdso.h rename to arch/mips/include/asm/vdso/vdso.h index 14b1931be69c..526695bc65ee 100644 --- a/arch/mips/vdso/vdso.h +++ b/arch/mips/include/asm/vdso/vdso.h @@ -68,14 +68,14 @@ static inline unsigned long get_vdso_base(void) return addr; } -static inline const union mips_vdso_data *get_vdso_data(void) +static inline const struct vdso_data *get_vdso_data(void) { - return (const union mips_vdso_data *)(get_vdso_base() - PAGE_SIZE); + return (const struct vdso_data *)(get_vdso_base() - PAGE_SIZE); } #ifdef CONFIG_CLKSRC_MIPS_GIC -static inline void __iomem *get_gic(const union mips_vdso_data *data) +static inline void __iomem *get_gic(const struct vdso_data *data) { return (void __iomem *)data - PAGE_SIZE; } diff --git a/arch/mips/include/asm/vdso/vsyscall.h b/arch/mips/include/asm/vdso/vsyscall.h new file mode 100644 index 000000000000..195314732233 --- /dev/null +++ b/arch/mips/include/asm/vdso/vsyscall.h @@ -0,0 +1,43 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ASM_VDSO_VSYSCALL_H +#define __ASM_VDSO_VSYSCALL_H + +#ifndef __ASSEMBLY__ + +#include +#include + +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 + +static __always_inline +int __mips_get_clock_mode(struct timekeeper *tk) +{ + u32 clock_mode = tk->tkr_mono.clock->archdata.vdso_clock_mode; + + return clock_mode; +} +#define __arch_get_clock_mode __mips_get_clock_mode + +static __always_inline +int __mips_use_vsyscall(struct vdso_data *vdata) +{ + return (vdata[CS_HRES_COARSE].clock_mode != VDSO_CLOCK_NONE); +} +#define __arch_use_vsyscall __mips_use_vsyscall + +/* The asm-generic header needs to be included after the definitions above */ +#include + +#endif /* !__ASSEMBLY__ */ + +#endif /* __ASM_VDSO_VSYSCALL_H */ diff --git a/arch/mips/kernel/vdso.c b/arch/mips/kernel/vdso.c index 3a372686ffca..bc35f8499111 100644 --- a/arch/mips/kernel/vdso.c +++ b/arch/mips/kernel/vdso.c @@ -20,9 +20,12 @@ #include #include #include +#include +#include /* Kernel-provided data used by the VDSO. */ -static union mips_vdso_data vdso_data __page_aligned_data; +static union mips_vdso_data mips_vdso_data __page_aligned_data; +struct vdso_data *vdso_data = mips_vdso_data.data; /* * Mapping for the VDSO data/GIC pages. The real pages are mapped manually, as @@ -66,34 +69,6 @@ static int __init init_vdso(void) } subsys_initcall(init_vdso); -void update_vsyscall(struct timekeeper *tk) -{ - vdso_data_write_begin(&vdso_data); - - vdso_data.xtime_sec = tk->xtime_sec; - vdso_data.xtime_nsec = tk->tkr_mono.xtime_nsec; - vdso_data.wall_to_mono_sec = tk->wall_to_monotonic.tv_sec; - vdso_data.wall_to_mono_nsec = tk->wall_to_monotonic.tv_nsec; - vdso_data.cs_shift = tk->tkr_mono.shift; - - vdso_data.clock_mode = tk->tkr_mono.clock->archdata.vdso_clock_mode; - if (vdso_data.clock_mode != VDSO_CLOCK_NONE) { - vdso_data.cs_mult = tk->tkr_mono.mult; - vdso_data.cs_cycle_last = tk->tkr_mono.cycle_last; - vdso_data.cs_mask = tk->tkr_mono.mask; - } - - vdso_data_write_end(&vdso_data); -} - -void update_vsyscall_tz(void) -{ - if (vdso_data.clock_mode != VDSO_CLOCK_NONE) { - vdso_data.tz_minuteswest = sys_tz.tz_minuteswest; - vdso_data.tz_dsttime = sys_tz.tz_dsttime; - } -} - static unsigned long vdso_base(void) { unsigned long base; @@ -163,7 +138,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) */ if (cpu_has_dc_aliases) { base = __ALIGN_MASK(base, shm_align_mask); - base += ((unsigned long)&vdso_data - gic_size) & shm_align_mask; + base += ((unsigned long)vdso_data - gic_size) & shm_align_mask; } data_addr = base + gic_size; @@ -189,7 +164,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) /* Map data page. */ ret = remap_pfn_range(vma, data_addr, - virt_to_phys(&vdso_data) >> PAGE_SHIFT, + virt_to_phys(vdso_data) >> PAGE_SHIFT, PAGE_SIZE, PAGE_READONLY); if (ret) goto out; diff --git a/arch/mips/vdso/Makefile b/arch/mips/vdso/Makefile index 7221df24cb23..de853c6aab28 100644 --- a/arch/mips/vdso/Makefile +++ b/arch/mips/vdso/Makefile @@ -1,6 +1,12 @@ # SPDX-License-Identifier: GPL-2.0 # Objects to go into the VDSO. -obj-vdso-y := elf.o gettimeofday.o sigreturn.o + +# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before +# the inclusion of generic Makefile. +ARCH_REL_TYPE_ABS := R_MIPS_JUMP_SLOT|R_MIPS_GLOB_DAT +include $(srctree)/lib/vdso/Makefile + +obj-vdso-y := elf.o vgettimeofday.o sigreturn.o # Common compiler flags between ABIs. ccflags-vdso := \ @@ -15,15 +21,31 @@ ifdef CONFIG_CC_IS_CLANG ccflags-vdso += $(filter --target=%,$(KBUILD_CFLAGS)) endif +# +# The -fno-jump-tables flag only prevents the compiler from generating +# jump tables but does not prevent the compiler from emitting absolute +# offsets. cflags-vdso := $(ccflags-vdso) \ $(filter -W%,$(filter-out -Wa$(comma)%,$(KBUILD_CFLAGS))) \ - -O2 -g -fPIC -fno-strict-aliasing -fno-common -fno-builtin -G 0 \ - -DDISABLE_BRANCH_PROFILING \ + -O3 -g -fPIC -fno-strict-aliasing -fno-common -fno-builtin -G 0 \ + -fno-stack-protector -fno-jump-tables -DDISABLE_BRANCH_PROFILING \ $(call cc-option, -fno-asynchronous-unwind-tables) \ $(call cc-option, -fno-stack-protector) aflags-vdso := $(ccflags-vdso) \ -D__ASSEMBLY__ -Wa,-gdwarf-2 +ifneq ($(c-gettimeofday-y),) +CFLAGS_vgettimeofday.o = -include $(c-gettimeofday-y) + +# config-n32-o32-env.c prepares the environment to build a 32bit vDSO +# library on a 64bit kernel. +# Note: Needs to be included before than the generic library. +CFLAGS_vgettimeofday-o32.o = -include $(src)/config-n32-o32-env.c -include $(c-gettimeofday-y) +CFLAGS_vgettimeofday-n32.o = -include $(src)/config-n32-o32-env.c -include $(c-gettimeofday-y) +endif + +CFLAGS_REMOVE_vgettimeofday.o = -pg + # # For the pre-R6 code in arch/mips/vdso/vdso.h for locating # the base address of VDSO, the linker will emit a R_MIPS_PC32 @@ -48,6 +70,8 @@ VDSO_LDFLAGS := \ $(addprefix -Wl$(comma),$(filter -E%,$(KBUILD_CFLAGS))) \ -nostdlib -shared -Wl,--hash-style=sysv -Wl,--build-id +CFLAGS_REMOVE_vdso.o = -pg + GCOV_PROFILE := n UBSAN_SANITIZE := n @@ -96,6 +120,7 @@ $(obj)/vdso.lds: KBUILD_CPPFLAGS := $(ccflags-vdso) $(native-abi) $(obj)/vdso.so.dbg.raw: $(obj)/vdso.lds $(obj-vdso) FORCE $(call if_changed,vdsold) + $(call if_changed,vdso_check) $(obj)/vdso-image.c: $(obj)/vdso.so.dbg.raw $(obj)/vdso.so.raw \ $(obj)/genvdso FORCE @@ -134,6 +159,7 @@ $(obj)/vdso-o32.lds: $(src)/vdso.lds.S FORCE $(obj)/vdso-o32.so.dbg.raw: $(obj)/vdso-o32.lds $(obj-vdso-o32) FORCE $(call if_changed,vdsold) + $(call if_changed,vdso_check) $(obj)/vdso-o32-image.c: VDSO_NAME := o32 $(obj)/vdso-o32-image.c: $(obj)/vdso-o32.so.dbg.raw $(obj)/vdso-o32.so.raw \ @@ -174,6 +200,7 @@ $(obj)/vdso-n32.lds: $(src)/vdso.lds.S FORCE $(obj)/vdso-n32.so.dbg.raw: $(obj)/vdso-n32.lds $(obj-vdso-n32) FORCE $(call if_changed,vdsold) + $(call if_changed,vdso_check) $(obj)/vdso-n32-image.c: VDSO_NAME := n32 $(obj)/vdso-n32-image.c: $(obj)/vdso-n32.so.dbg.raw $(obj)/vdso-n32.so.raw \ diff --git a/arch/mips/vdso/config-n32-o32-env.c b/arch/mips/vdso/config-n32-o32-env.c new file mode 100644 index 000000000000..da4994b2b3e5 --- /dev/null +++ b/arch/mips/vdso/config-n32-o32-env.c @@ -0,0 +1,17 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Configuration file for O32 and N32 binaries. + * Note: To be included before lib/vdso/gettimeofday.c + */ +#if defined(CONFIG_MIPS32_O32) || defined(CONFIG_MIPS32_N32) +/* + * In case of a 32 bit VDSO for a 64 bit kernel fake a 32 bit kernel + * configuration. + */ +#undef CONFIG_64BIT + +#define CONFIG_32BIT 1 +#define CONFIG_GENERIC_ATOMIC64 1 + +#endif + diff --git a/arch/mips/vdso/elf.S b/arch/mips/vdso/elf.S index e7543e8f426c..a25cb147f1ca 100644 --- a/arch/mips/vdso/elf.S +++ b/arch/mips/vdso/elf.S @@ -4,7 +4,7 @@ * Author: Alex Smith */ -#include "vdso.h" +#include #include diff --git a/arch/mips/vdso/sigreturn.S b/arch/mips/vdso/sigreturn.S index c3597632874b..e5c0ab98ab46 100644 --- a/arch/mips/vdso/sigreturn.S +++ b/arch/mips/vdso/sigreturn.S @@ -4,7 +4,7 @@ * Author: Alex Smith */ -#include "vdso.h" +#include #include diff --git a/arch/mips/vdso/vgettimeofday.c b/arch/mips/vdso/vgettimeofday.c new file mode 100644 index 000000000000..1c46dace041e --- /dev/null +++ b/arch/mips/vdso/vgettimeofday.c @@ -0,0 +1,40 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * MIPS64 and compat userspace implementations of gettimeofday() + * and similar. + * + * Copyright (C) 2015 Imagination Technologies + * Copyright (C) 2018 ARM Limited + * + */ +#include +#include + +#if _MIPS_SIM != _MIPS_SIM_ABI64 +int __vdso_clock_gettime(clockid_t clock, + struct old_timespec32 *ts) +{ + return __cvdso_clock_gettime32(clock, ts); +} + +int __vdso_gettimeofday(struct __kernel_old_timeval *tv, + struct timezone *tz) +{ + return __cvdso_gettimeofday(tv, tz); +} + +#else + +int __vdso_clock_gettime(clockid_t clock, + struct __kernel_timespec *ts) +{ + return __cvdso_clock_gettime(clock, ts); +} + +int __vdso_gettimeofday(struct __kernel_old_timeval *tv, + struct timezone *tz) +{ + return __cvdso_gettimeofday(tv, tz); +} + +#endif