diff options
45 files changed, 1805 insertions, 51 deletions
diff --git a/Documentation/riscv/hwprobe.rst b/Documentation/riscv/hwprobe.rst index 9f0dd62dcb5d..7431d9d01c73 100644 --- a/Documentation/riscv/hwprobe.rst +++ b/Documentation/riscv/hwprobe.rst @@ -64,6 +64,9 @@ The following keys are defined: * :c:macro:`RISCV_HWPROBE_IMA_C`: The C extension is supported, as defined by version 2.2 of the RISC-V ISA manual. + * :c:macro:`RISCV_HWPROBE_IMA_V`: The V extension is supported, as defined by + version 1.0 of the RISC-V Vector extension manual. + * :c:macro:`RISCV_HWPROBE_KEY_CPUPERF_0`: A bitmask that contains performance information about the selected set of processors. diff --git a/Documentation/riscv/index.rst b/Documentation/riscv/index.rst index 175a91db0200..95cf9c1e1da1 100644 --- a/Documentation/riscv/index.rst +++ b/Documentation/riscv/index.rst @@ -10,6 +10,7 @@ RISC-V architecture hwprobe patch-acceptance uabi + vector features diff --git a/Documentation/riscv/vector.rst b/Documentation/riscv/vector.rst new file mode 100644 index 000000000000..48f189d79e41 --- /dev/null +++ b/Documentation/riscv/vector.rst @@ -0,0 +1,132 @@ +.. SPDX-License-Identifier: GPL-2.0 + +========================================= +Vector Extension Support for RISC-V Linux +========================================= + +This document briefly outlines the interface provided to userspace by Linux in +order to support the use of the RISC-V Vector Extension. + +1. prctl() Interface +--------------------- + +Two new prctl() calls are added to allow programs to manage the enablement +status for the use of Vector in userspace. The intended usage guideline for +these interfaces is to give init systems a way to modify the availability of V +for processes running under its domain. Calling thess interfaces is not +recommended in libraries routines because libraries should not override policies +configured from the parant process. Also, users must noted that these interfaces +are not portable to non-Linux, nor non-RISC-V environments, so it is discourage +to use in a portable code. To get the availability of V in an ELF program, +please read :c:macro:`COMPAT_HWCAP_ISA_V` bit of :c:macro:`ELF_HWCAP` in the +auxiliary vector. + +* prctl(PR_RISCV_V_SET_CONTROL, unsigned long arg) + + Sets the Vector enablement status of the calling thread, where the control + argument consists of two 2-bit enablement statuses and a bit for inheritance + mode. Other threads of the calling process are unaffected. + + Enablement status is a tri-state value each occupying 2-bit of space in + the control argument: + + * :c:macro:`PR_RISCV_V_VSTATE_CTRL_DEFAULT`: Use the system-wide default + enablement status on execve(). The system-wide default setting can be + controlled via sysctl interface (see sysctl section below). + + * :c:macro:`PR_RISCV_V_VSTATE_CTRL_ON`: Allow Vector to be run for the + thread. + + * :c:macro:`PR_RISCV_V_VSTATE_CTRL_OFF`: Disallow Vector. Executing Vector + instructions under such condition will trap and casuse the termination of the thread. + + arg: The control argument is a 5-bit value consisting of 3 parts, and + accessed by 3 masks respectively. + + The 3 masks, PR_RISCV_V_VSTATE_CTRL_CUR_MASK, + PR_RISCV_V_VSTATE_CTRL_NEXT_MASK, and PR_RISCV_V_VSTATE_CTRL_INHERIT + represents bit[1:0], bit[3:2], and bit[4]. bit[1:0] accounts for the + enablement status of current thread, and the setting at bit[3:2] takes place + at next execve(). bit[4] defines the inheritance mode of the setting in + bit[3:2]. + + * :c:macro:`PR_RISCV_V_VSTATE_CTRL_CUR_MASK`: bit[1:0]: Account for the + Vector enablement status for the calling thread. The calling thread is + not able to turn off Vector once it has been enabled. The prctl() call + fails with EPERM if the value in this mask is PR_RISCV_V_VSTATE_CTRL_OFF + but the current enablement status is not off. Setting + PR_RISCV_V_VSTATE_CTRL_DEFAULT here takes no effect but to set back + the original enablement status. + + * :c:macro:`PR_RISCV_V_VSTATE_CTRL_NEXT_MASK`: bit[3:2]: Account for the + Vector enablement setting for the calling thread at the next execve() + system call. If PR_RISCV_V_VSTATE_CTRL_DEFAULT is used in this mask, + then the enablement status will be decided by the system-wide + enablement status when execve() happen. + + * :c:macro:`PR_RISCV_V_VSTATE_CTRL_INHERIT`: bit[4]: the inheritance + mode for the setting at PR_RISCV_V_VSTATE_CTRL_NEXT_MASK. If the bit + is set then the following execve() will not clear the setting in both + PR_RISCV_V_VSTATE_CTRL_NEXT_MASK and PR_RISCV_V_VSTATE_CTRL_INHERIT. + This setting persists across changes in the system-wide default value. + + Return value: + * 0 on success; + * EINVAL: Vector not supported, invalid enablement status for current or + next mask; + * EPERM: Turning off Vector in PR_RISCV_V_VSTATE_CTRL_CUR_MASK if Vector + was enabled for the calling thread. + + On success: + * A valid setting for PR_RISCV_V_VSTATE_CTRL_CUR_MASK takes place + immediately. The enablement status specified in + PR_RISCV_V_VSTATE_CTRL_NEXT_MASK happens at the next execve() call, or + all following execve() calls if PR_RISCV_V_VSTATE_CTRL_INHERIT bit is + set. + * Every successful call overwrites a previous setting for the calling + thread. + +* prctl(PR_RISCV_V_GET_CONTROL) + + Gets the same Vector enablement status for the calling thread. Setting for + next execve() call and the inheritance bit are all OR-ed together. + + Note that ELF programs are able to get the availability of V for itself by + reading :c:macro:`COMPAT_HWCAP_ISA_V` bit of :c:macro:`ELF_HWCAP` in the + auxiliary vector. + + Return value: + * a nonnegative value on success; + * EINVAL: Vector not supported. + +2. System runtime configuration (sysctl) +----------------------------------------- + +To mitigate the ABI impact of expansion of the signal stack, a +policy mechanism is provided to the administrators, distro maintainers, and +developers to control the default Vector enablement status for userspace +processes in form of sysctl knob: + +* /proc/sys/abi/riscv_v_default_allow + + Writing the text representation of 0 or 1 to this file sets the default + system enablement status for new starting userspace programs. Valid values + are: + + * 0: Do not allow Vector code to be executed as the default for new processes. + * 1: Allow Vector code to be executed as the default for new processes. + + Reading this file returns the current system default enablement status. + + At every execve() call, a new enablement status of the new process is set to + the system default, unless: + + * PR_RISCV_V_VSTATE_CTRL_INHERIT is set for the calling process, and the + setting in PR_RISCV_V_VSTATE_CTRL_NEXT_MASK is not + PR_RISCV_V_VSTATE_CTRL_DEFAULT. Or, + + * The setting in PR_RISCV_V_VSTATE_CTRL_NEXT_MASK is not + PR_RISCV_V_VSTATE_CTRL_DEFAULT. + + Modifying the system default enablement status does not affect the enablement + status of any existing process of thread that do not make an execve() call. diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 491ecd7d2336..a3d54cd14fca 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -264,6 +264,12 @@ config RISCV_DMA_NONCOHERENT config AS_HAS_INSN def_bool $(as-instr,.insn r 51$(comma) 0$(comma) 0$(comma) t0$(comma) t0$(comma) zero) +config AS_HAS_OPTION_ARCH + # https://reviews.llvm.org/D123515 + def_bool y + depends on $(as-instr, .option arch$(comma) +m) + depends on !$(as-instr, .option arch$(comma) -i) + source "arch/riscv/Kconfig.socs" source "arch/riscv/Kconfig.errata" @@ -462,13 +468,44 @@ config RISCV_ISA_SVPBMT If you don't know what to do here, say Y. +config TOOLCHAIN_HAS_V + bool + default y + depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64iv) + depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32iv) + depends on LLD_VERSION >= 140000 || LD_VERSION >= 23800 + depends on AS_HAS_OPTION_ARCH + +config RISCV_ISA_V + bool "VECTOR extension support" + depends on TOOLCHAIN_HAS_V + depends on FPU + select DYNAMIC_SIGFRAME + default y + help + Say N here if you want to disable all vector related procedure + in the kernel. + + If you don't know what to do here, say Y. + +config RISCV_ISA_V_DEFAULT_ENABLE + bool "Enable userspace Vector by default" + depends on RISCV_ISA_V + default y + help + Say Y here if you want to enable Vector in userspace by default. + Otherwise, userspace has to make explicit prctl() call to enable + Vector, or enable it via the sysctl interface. + + If you don't know what to do here, say Y. + config TOOLCHAIN_HAS_ZBB bool default y depends on !64BIT || $(cc-option,-mabi=lp64 -march=rv64ima_zbb) depends on !32BIT || $(cc-option,-mabi=ilp32 -march=rv32ima_zbb) depends on LLD_VERSION >= 150000 || LD_VERSION >= 23900 - depends on AS_IS_GNU + depends on AS_HAS_OPTION_ARCH config RISCV_ISA_ZBB bool "Zbb extension support for bit manipulation instructions" diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile index 0fb256bf8270..6ec6d52a4180 100644 --- a/arch/riscv/Makefile +++ b/arch/riscv/Makefile @@ -60,6 +60,7 @@ riscv-march-$(CONFIG_ARCH_RV32I) := rv32ima riscv-march-$(CONFIG_ARCH_RV64I) := rv64ima riscv-march-$(CONFIG_FPU) := $(riscv-march-y)fd riscv-march-$(CONFIG_RISCV_ISA_C) := $(riscv-march-y)c +riscv-march-$(CONFIG_RISCV_ISA_V) := $(riscv-march-y)v ifdef CONFIG_TOOLCHAIN_NEEDS_OLD_ISA_SPEC KBUILD_CFLAGS += -Wa,-misa-spec=2.2 @@ -71,7 +72,10 @@ endif # Check if the toolchain supports Zihintpause extension riscv-march-$(CONFIG_TOOLCHAIN_HAS_ZIHINTPAUSE) := $(riscv-march-y)_zihintpause -KBUILD_CFLAGS += -march=$(subst fd,,$(riscv-march-y)) +# Remove F,D,V from isa string for all. Keep extensions between "fd" and "v" by +# matching non-v and non-multi-letter extensions out with the filter ([^v_]*) +KBUILD_CFLAGS += -march=$(shell echo $(riscv-march-y) | sed -E 's/(rv32ima|rv64ima)fd([^v_]*)v?/\1\2/') + KBUILD_AFLAGS += -march=$(riscv-march-y) KBUILD_CFLAGS += -mno-save-restore diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h index b6acb7ed115f..b98b3b6c9da2 100644 --- a/arch/riscv/include/asm/csr.h +++ b/arch/riscv/include/asm/csr.h @@ -24,16 +24,24 @@ #define SR_FS_CLEAN _AC(0x00004000, UL) #define SR_FS_DIRTY _AC(0x00006000, UL) +#define SR_VS _AC(0x00000600, UL) /* Vector Status */ +#define SR_VS_OFF _AC(0x00000000, UL) +#define SR_VS_INITIAL _AC(0x00000200, UL) +#define SR_VS_CLEAN _AC(0x00000400, UL) +#define SR_VS_DIRTY _AC(0x00000600, UL) + #define SR_XS _AC(0x00018000, UL) /* Extension Status */ #define SR_XS_OFF _AC(0x00000000, UL) #define SR_XS_INITIAL _AC(0x00008000, UL) #define SR_XS_CLEAN _AC(0x00010000, UL) #define SR_XS_DIRTY _AC(0x00018000, UL) +#define SR_FS_VS (SR_FS | SR_VS) /* Vector and Floating-Point Unit */ + #ifndef CONFIG_64BIT -#define SR_SD _AC(0x80000000, UL) /* FS/XS dirty */ +#define SR_SD _AC(0x80000000, UL) /* FS/VS/XS dirty */ #else -#define SR_SD _AC(0x8000000000000000, UL) /* FS/XS dirty */ +#define SR_SD _AC(0x8000000000000000, UL) /* FS/VS/XS dirty */ #endif #ifdef CONFIG_64BIT @@ -375,6 +383,12 @@ #define CSR_MVIPH 0x319 #define CSR_MIPH 0x354 +#define CSR_VSTART 0x8 +#define CSR_VCSR 0xf +#define CSR_VL 0xc20 +#define CSR_VTYPE 0xc21 +#define CSR_VLENB 0xc22 + #ifdef CONFIG_RISCV_M_MODE # define CSR_STATUS CSR_MSTATUS # define CSR_IE CSR_MIE diff --git a/arch/riscv/include/asm/elf.h b/arch/riscv/include/asm/elf.h index 30e7d2455960..c24280774caf 100644 --- a/arch/riscv/include/asm/elf.h +++ b/arch/riscv/include/asm/elf.h @@ -66,7 +66,7 @@ extern bool compat_elf_check_arch(Elf32_Ehdr *hdr); * via a bitmap that coorespends to each single-letter ISA extension. This is * essentially defunct, but will remain for compatibility with userspace. */ -#define ELF_HWCAP (elf_hwcap & ((1UL << RISCV_ISA_EXT_BASE) - 1)) +#define ELF_HWCAP riscv_get_elf_hwcap() extern unsigned long elf_hwcap; /* @@ -105,6 +105,15 @@ do { \ get_cache_size(3, CACHE_TYPE_UNIFIED)); \ NEW_AUX_ENT(AT_L3_CACHEGEOMETRY, \ get_cache_geometry(3, CACHE_TYPE_UNIFIED)); \ + /* \ + * Should always be nonzero unless there's a kernel bug. \ + * If we haven't determined a sensible value to give to \ + * userspace, omit the entry: \ + */ \ + if (likely(signal_minsigstksz)) \ + NEW_AUX_ENT(AT_MINSIGSTKSZ, signal_minsigstksz); \ + else \ + NEW_AUX_ENT(AT_IGNORE, 0); \ } while (0) #define ARCH_HAS_SETUP_ADDITIONAL_PAGES struct linux_binprm; diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h index e0c40a4c63d5..e6c288ac4581 100644 --- a/arch/riscv/include/asm/hwcap.h +++ b/arch/riscv/include/asm/hwcap.h @@ -22,6 +22,7 @@ #define RISCV_ISA_EXT_m ('m' - 'a') #define RISCV_ISA_EXT_s ('s' - 'a') #define RISCV_ISA_EXT_u ('u' - 'a') +#define RISCV_ISA_EXT_v ('v' - 'a') /* * These macros represent the logical IDs of each multi-letter RISC-V ISA @@ -60,6 +61,8 @@ #include <linux/jump_label.h> +unsigned long riscv_get_elf_hwcap(void); + struct riscv_isa_ext_data { /* Name of the extension displayed to userspace via /proc/cpuinfo */ char uprop[RISCV_ISA_EXT_NAME_LEN_MAX]; diff --git a/arch/riscv/include/asm/insn.h b/arch/riscv/include/asm/insn.h index 8d5c84f2d5ef..4e1505cef8aa 100644 --- a/arch/riscv/include/asm/insn.h +++ b/arch/riscv/include/asm/insn.h @@ -137,6 +137,26 @@ #define RVG_OPCODE_JALR 0x67 #define RVG_OPCODE_JAL 0x6f #define RVG_OPCODE_SYSTEM 0x73 +#define RVG_SYSTEM_CSR_OFF 20 +#define RVG_SYSTEM_CSR_MASK GENMASK(12, 0) + +/* parts of opcode for RVF, RVD and RVQ */ +#define RVFDQ_FL_FS_WIDTH_OFF 12 +#define RVFDQ_FL_FS_WIDTH_MASK GENMASK(3, 0) +#define RVFDQ_FL_FS_WIDTH_W 2 +#define RVFDQ_FL_FS_WIDTH_D 3 +#define RVFDQ_LS_FS_WIDTH_Q 4 +#define RVFDQ_OPCODE_FL 0x07 +#define RVFDQ_OPCODE_FS 0x27 + +/* parts of opcode for RVV */ +#define RVV_OPCODE_VECTOR 0x57 +#define RVV_VL_VS_WIDTH_8 0 +#define RVV_VL_VS_WIDTH_16 5 +#define RVV_VL_VS_WIDTH_32 6 +#define RVV_VL_VS_WIDTH_64 7 +#define RVV_OPCODE_VL RVFDQ_OPCODE_FL +#define RVV_OPCODE_VS RVFDQ_OPCODE_FS /* parts of opcode for RVC*/ #define RVC_OPCODE_C0 0x0 @@ -304,6 +324,15 @@ static __always_inline bool riscv_insn_is_branch(u32 code) (RVC_X(x_, RVC_B_IMM_7_6_OPOFF, RVC_B_IMM_7_6_MASK) << RVC_B_IMM_7_6_OFF) | \ (RVC_IMM_SIGN(x_) << RVC_B_IMM_SIGN_OFF); }) +#define RVG_EXTRACT_SYSTEM_CSR(x) \ + ({typeof(x) x_ = (x); RV_X(x_, RVG_SYSTEM_CSR_OFF, RVG_SYSTEM_CSR_MASK); }) + +#define RVFDQ_EXTRACT_FL_FS_WIDTH(x) \ + ({typeof(x) x_ = (x); RV_X(x_, RVFDQ_FL_FS_WIDTH_OFF, \ + RVFDQ_FL_FS_WIDTH_MASK); }) + +#define RVV_EXRACT_VL_VS_WIDTH(x) RVFDQ_EXTRACT_FL_FS_WIDTH(x) + /* * Get the immediate from a J-type instruction. * diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h index ee0acccb1d3b..bd47a1dc2ff8 100644 --- a/arch/riscv/include/asm/kvm_host.h +++ b/arch/riscv/include/asm/kvm_host.h @@ -15,6 +15,7 @@ #include <linux/spinlock.h> #include <asm/hwcap.h> #include <asm/kvm_aia.h> +#include <asm/ptrace.h> #include <asm/kvm_vcpu_fp.h> #include <asm/kvm_vcpu_insn.h> #include <asm/kvm_vcpu_sbi.h> @@ -145,6 +146,7 @@ struct kvm_cpu_context { unsigned long sstatus; unsigned long hstatus; union __riscv_fp_state fp; + struct __riscv_v_ext_state vector; }; struct kvm_vcpu_csr { diff --git a/arch/riscv/include/asm/kvm_vcpu_vector.h b/arch/riscv/include/asm/kvm_vcpu_vector.h new file mode 100644 index 000000000000..ff994fdd6d0d --- /dev/null +++ b/arch/riscv/include/asm/kvm_vcpu_vector.h @@ -0,0 +1,82 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2022 SiFive + * + * Authors: + * Vincent Chen <vincent.chen@sifive.com> + * Greentime Hu <greentime.hu@sifive.com> + */ + +#ifndef __KVM_VCPU_RISCV_VECTOR_H +#define __KVM_VCPU_RISCV_VECTOR_H + +#include <linux/types.h> + +#ifdef CONFIG_RISCV_ISA_V +#include <asm/vector.h> +#include <asm/kvm_host.h> + +static __always_inline void __kvm_riscv_vector_save(struct kvm_cpu_context *context) +{ + __riscv_v_vstate_save(&context->vector, context->vector.datap); +} + +static __always_inline void __kvm_riscv_vector_restore(struct kvm_cpu_context *context) +{ + __riscv_v_vstate_restore(&context->vector, context->vector.datap); +} + +void kvm_riscv_vcpu_vector_reset(struct kvm_vcpu *vcpu); +void kvm_riscv_vcpu_guest_vector_save(struct kvm_cpu_context *cntx, + unsigned long *isa); +void kvm_riscv_vcpu_guest_vector_restore(struct kvm_cpu_context *cntx, + unsigned long *isa); +void kvm_riscv_vcpu_host_vector_save(struct kvm_cpu_context *cntx); +void kvm_riscv_vcpu_host_vector_restore(struct kvm_cpu_context *cntx); +int kvm_riscv_vcpu_alloc_vector_context(struct kvm_vcpu *vcpu, + struct kvm_cpu_context *cntx); +void kvm_riscv_vcpu_free_vector_context(struct kvm_vcpu *vcpu); +#else + +struct kvm_cpu_context; + +static inline void kvm_riscv_vcpu_vector_reset(struct kvm_vcpu *vcpu) +{ +} + +static inline void kvm_riscv_vcpu_guest_vector_save(struct kvm_cpu_context *cntx, + unsigned long *isa) +{ +} + +static inline void kvm_riscv_vcpu_guest_vector_restore(struct kvm_cpu_context *cntx, + unsigned long *isa) +{ +} + +static inline void kvm_riscv_vcpu_host_vector_save(struct kvm_cpu_context *cntx) +{ +} + +static inline void kvm_riscv_vcpu_host_vector_restore(struct kvm_cpu_context *cntx) +{ +} + +static inline int kvm_riscv_vcpu_alloc_vector_context(struct kvm_vcpu *vcpu, + struct kvm_cpu_context *cntx) +{ + return 0; +} + +static inline void kvm_riscv_vcpu_free_vector_context(struct kvm_vcpu *vcpu) +{ +} +#endif + +int kvm_riscv_vcpu_get_reg_vector(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg, + unsigned long rtype); +int kvm_riscv_vcpu_set_reg_vector(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg, + unsigned long rtype); +#endif diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h index 94a0590c6971..e82af1097e26 100644 --- a/arch/riscv/include/asm/processor.h +++ b/arch/riscv/include/asm/processor.h @@ -7,6 +7,7 @@ #define _ASM_RISCV_PROCESSOR_H #include <linux/const.h> +#include <linux/cache.h> #include <vdso/processor.h> @@ -39,6 +40,8 @@ struct thread_struct { unsigned long s[12]; /* s[0]: frame pointer */ struct __riscv_d_ext_state fstate; unsigned long bad_cause; + unsigned long vstate_ctrl; + struct __riscv_v_ext_state vstate; }; /* Whitelist the fstate from the task_struct for hardened usercopy */ @@ -80,6 +83,16 @@ int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid); extern void riscv_fill_hwcap(void); extern int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src); +extern unsigned long signal_minsigstksz __ro_after_init; + +#ifdef CONFIG_RISCV_ISA_V +/* Userspace interface for PR_RISCV_V_{SET,GET}_VS prctl()s: */ +#define RISCV_V_SET_CONTROL(arg) riscv_v_vstate_ctrl_set_current(arg) +#define RISCV_V_GET_CONTROL() riscv_v_vstate_ctrl_get_current() +extern long riscv_v_vstate_ctrl_set_current(unsigned long arg); +extern long riscv_v_vstate_ctrl_get_current(void); +#endif /* CONFIG_RISCV_ISA_V */ + #endif /* __ASSEMBLY__ */ #endif /* _ASM_RISCV_PROCESSOR_H */ diff --git a/arch/riscv/include/asm/switch_to.h b/arch/riscv/include/asm/switch_to.h index 60f8ca01d36e..a727be723c56 100644 --- a/arch/riscv/include/asm/switch_to.h +++ b/arch/riscv/include/asm/switch_to.h @@ -8,6 +8,7 @@ #include <linux/jump_label.h> #include <linux/sched/task_stack.h> +#include <asm/vector.h> #include <asm/hwcap.h> #include <asm/processor.h> #include <asm/ptrace.h> @@ -46,7 +47,7 @@ static inline void fstate_restore(struct task_struct *task, } } -static inline void __switch_to_aux(struct task_struct *prev, +static inline void __switch_to_fpu(struct task_struct *prev, struct task_struct *next) { struct pt_regs *regs; @@ -66,7 +67,7 @@ static __always_inline bool has_fpu(void) static __always_inline bool has_fpu(void) { return false; } #define fstate_save(task, regs) do { } while (0) #define fstate_restore(task, regs) do { } while (0) -#define __switch_to_aux(__prev, __next) do { } while (0) +#define __switch_to_fpu(__prev, __next) do { } while (0) #endif extern struct task_struct *__switch_to(struct task_struct *, @@ -77,7 +78,9 @@ do { \ struct task_struct *__prev = (prev); \ struct task_struct *__next = (next); \ if (has_fpu()) \ - __switch_to_aux(__prev, __next); \ + __switch_to_fpu(__prev, __next); \ + if (has_vector()) \ + __switch_to_vector(__prev, __next); \ ((last) = __switch_to(__prev, __next)); \ } while (0) diff --git a/arch/riscv/include/asm/thread_info.h b/arch/riscv/include/asm/thread_info.h index e0d202134b44..97e6f65ec176 100644 --- a/arch/riscv/include/asm/thread_info.h +++ b/arch/riscv/include/asm/thread_info.h @@ -81,6 +81,9 @@ struct thread_info { .preempt_count = INIT_PREEMPT_COUNT, \ } +void arch_release_task_struct(struct task_struct *tsk); +int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src); + #endif /* !__ASSEMBLY__ */ /* diff --git a/arch/riscv/include/asm/vector.h b/arch/riscv/include/asm/vector.h new file mode 100644 index 000000000000..04c0b07bf6cd --- /dev/null +++ b/arch/riscv/include/asm/vector.h @@ -0,0 +1,184 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2020 SiFive + */ + +#ifndef __ASM_RISCV_VECTOR_H +#define __ASM_RISCV_VECTOR_H + +#include <linux/types.h> +#include <uapi/asm-generic/errno.h> + +#ifdef CONFIG_RISCV_ISA_V + +#include <linux/stringify.h> +#include <linux/sched.h> +#include <linux/sched/task_stack.h> +#include <asm/ptrace.h> +#include <asm/hwcap.h> +#include <asm/csr.h> +#include <asm/asm.h> + +extern unsigned long riscv_v_vsize; +int riscv_v_setup_vsize(void); +bool riscv_v_first_use_handler(struct pt_regs *regs); + +static __always_inline bool has_vector(void) +{ + return riscv_has_extension_unlikely(RISCV_ISA_EXT_v); +} + +static inline void __riscv_v_vstate_clean(struct pt_regs *regs) +{ + regs->status = (regs->status & ~SR_VS) | SR_VS_CLEAN; +} + +static inline void riscv_v_vstate_off(struct pt_regs *regs) +{ + regs->status = (regs->status & ~SR_VS) | SR_VS_OFF; +} + +static inline void riscv_v_vstate_on(struct pt_regs *regs) +{ + regs->status = (regs->status & ~SR_VS) | SR_VS_INITIAL; +} + +static inline bool riscv_v_vstate_query(struct pt_regs *regs) +{ + return (regs->status & SR_VS) != 0; +} + +static __always_inline void riscv_v_enable(void) +{ + csr_set(CSR_SSTATUS, SR_VS); +} + +static __always_inline void riscv_v_disable(void) +{ + csr_clear(CSR_SSTATUS, SR_VS); +} + +static __always_inline void __vstate_csr_save(struct __riscv_v_ext_state *dest) +{ + asm volatile ( + "csrr %0, " __stringify(CSR_VSTART) "\n\t" + "csrr %1, " __stringify(CSR_VTYPE) "\n\t" + "csrr %2, " __stringify(CSR_VL) "\n\t" + "csrr %3, " __stringify(CSR_VCSR) "\n\t" + : "=r" (dest->vstart), "=r" (dest->vtype), "=r" (dest->vl), + "=r" (dest->vcsr) : :); +} + +static __always_inline void __vstate_csr_restore(struct __riscv_v_ext_state *src) +{ + asm volatile ( + ".option push\n\t" + ".option arch, +v\n\t" + "vsetvl x0, %2, %1\n\t" + ".option pop\n\t" + "csrw " __stringify(CSR_VSTART) ", %0\n\t" + "csrw " __stringify(CSR_VCSR) ", %3\n\t" + : : "r" (src->vstart), "r" (src->vtype), "r" (src->vl), + "r" (src->vcsr) :); +} + +static inline void __riscv_v_vstate_save(struct __riscv_v_ext_state *save_to, + void *datap) +{ + unsigned long vl; + + riscv_v_enable(); + __vstate_csr_save(save_to); + asm volatile ( + ".option push\n\t" + ".option arch, +v\n\t" + "vsetvli %0, x0, e8, m8, ta, ma\n\t" + "vse8.v v0, (%1)\n\t" + "add %1, %1, %0\n\t" + "vse8.v v8, (%1)\n\t" + "add %1, %1, %0\n\t" + "vse8.v v16, (%1)\n\t" + "add %1, %1, %0\n\t" + "vse8.v v24, (%1)\n\t" + ".option pop\n\t" + : "=&r" (vl) : "r" (datap) : "memory"); + riscv_v_disable(); +} + +static inline void __riscv_v_vstate_restore(struct __riscv_v_ext_state *restore_from, + void *datap) +{ + unsigned long vl; + + riscv_v_enable(); + asm volatile ( + ".option push\n\t" + ".option arch, +v\n\t" + "vsetvli %0, x0, e8, m8, ta, ma\n\t" + "vle8.v v0, (%1)\n\t" + "add %1, %1, %0\n\t" + "vle8.v v8, (%1)\n\t" + "add %1, %1, %0\n\t" + "vle8.v v16, (%1)\n\t" + "add %1, %1, %0\n\t" + "vle8.v v24, (%1)\n\t" + ".option pop\n\t" + : "=&r" (vl) : "r" (datap) : "memory"); + __vstate_csr_restore(restore_from); + riscv_v_disable(); +} + +static inline void riscv_v_vstate_save(struct task_struct *task, + struct pt_regs *regs) +{ + if ((regs->status & SR_VS) == SR_VS_DIRTY) { + struct __riscv_v_ext_state *vstate = &task->thread.vstate; + + __riscv_v_vstate_save(vstate, vstate->datap); + __riscv_v_vstate_clean(regs); + } +} + +static inline void riscv_v_vstate_restore(struct task_struct *task, + struct pt_regs *regs) +{ + if ((regs->status & SR_VS) != SR_VS_OFF) { + struct __riscv_v_ext_state *vstate = &task->thread.vstate; + + __riscv_v_vstate_restore(vstate, vstate->datap); + __riscv_v_vstate_clean(regs); + } +} + +static inline void __switch_to_vector(struct task_struct *prev, + struct task_struct *next) +{ + struct pt_regs *regs; + + regs = task_pt_regs(prev); + riscv_v_vstate_save(prev, regs); + riscv_v_vstate_restore(next, task_pt_regs(next)); +} + +void riscv_v_vstate_ctrl_init(struct task_struct *tsk); +bool riscv_v_vstate_ctrl_user_allowed(void); + +#else /* ! CONFIG_RISCV_ISA_V */ + +struct pt_regs; + +static inline int riscv_v_setup_vsize(void) { return -EOPNOTSUPP; } +static __always_inline bool has_vector(void) { return false; } +static inline bool riscv_v_first_use_handler(struct pt_regs *regs) { return false; } +static inline bool riscv_v_vstate_query(struct pt_regs *regs) { return false; } +static inline bool riscv_v_vstate_ctrl_user_allowed(void) { return false; } +#define riscv_v_vsize (0) +#define riscv_v_vstate_save(task, regs) do {} while (0) +#define riscv_v_vstate_restore(task, regs) do {} while (0) +#define __switch_to_vector(__prev, __next) do {} while (0) +#define riscv_v_vstate_off(regs) do {} while (0) +#define riscv_v_vstate_on(regs) do {} while (0) + +#endif /* CONFIG_RISCV_ISA_V */ + +#endif /* ! __ASM_RISCV_VECTOR_H */ diff --git a/arch/riscv/include/uapi/asm/auxvec.h b/arch/riscv/include/uapi/asm/auxvec.h index fb187a33ce58..10aaa83db89e 100644 --- a/arch/riscv/include/uapi/asm/auxvec.h +++ b/arch/riscv/include/uapi/asm/auxvec.h @@ -35,5 +35,6 @@ /* entries in ARCH_DLINFO */ #define AT_VECTOR_SIZE_ARCH 9 +#define AT_MINSIGSTKSZ 51 #endif /* _UAPI_ASM_RISCV_AUXVEC_H */ diff --git a/arch/riscv/include/uapi/asm/hwcap.h b/arch/riscv/include/uapi/asm/hwcap.h index 46dc3f5ee99f..c52bb7bbbabe 100644 --- a/arch/riscv/include/uapi/asm/hwcap.h +++ b/arch/riscv/include/uapi/asm/hwcap.h @@ -21,5 +21,6 @@ #define COMPAT_HWCAP_ISA_F (1 << ('F' - 'A')) #define COMPAT_HWCAP_ISA_D (1 << ('D' - 'A')) #define COMPAT_HWCAP_ISA_C (1 << ('C' - 'A')) +#define COMPAT_HWCAP_ISA_V (1 << ('V' - 'A')) #endif /* _UAPI_ASM_RISCV_HWCAP_H */ diff --git a/arch/riscv/include/uapi/asm/hwprobe.h b/arch/riscv/include/uapi/asm/hwprobe.h index 8d745a4ad8a2..7c6fdcf7ced5 100644 --- a/arch/riscv/include/uapi/asm/hwprobe.h +++ b/arch/riscv/include/uapi/asm/hwprobe.h @@ -25,6 +25,7 @@ struct riscv_hwprobe { #define RISCV_HWPROBE_KEY_IMA_EXT_0 4 #define RISCV_HWPROBE_IMA_FD (1 << 0) #define RISCV_HWPROBE_IMA_C (1 << 1) +#define RISCV_HWPROBE_IMA_V (1 << 2) #define RISCV_HWPROBE_KEY_CPUPERF_0 5 #define RISCV_HWPROBE_MISALIGNED_UNKNOWN (0 << 0) #define RISCV_HWPROBE_MISALIGNED_EMULATED (1 << 0) diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h index f92790c9481a..855c047e86d4 100644 --- a/arch/riscv/include/uapi/asm/kvm.h +++ b/arch/riscv/include/uapi/asm/kvm.h @@ -121,6 +121,7 @@ enum KVM_RISCV_ISA_EXT_ID { KVM_RISCV_ISA_EXT_ZICBOZ, KVM_RISCV_ISA_EXT_ZBB, KVM_RISCV_ISA_EXT_SSAIA, + KVM_RISCV_ISA_EXT_V, KVM_RISCV_ISA_EXT_MAX, }; @@ -203,6 +204,13 @@ enum KVM_RISCV_SBI_EXT_ID { #define KVM_REG_RISCV_SBI_MULTI_REG_LAST \ KVM_REG_RISCV_SBI_MULTI_REG(KVM_RISCV_SBI_EXT_MAX - 1) +/* V extension registers are mapped as type 9 */ +#define KVM_REG_RISCV_VECTOR (0x09 << KVM_REG_RISCV_TYPE_SHIFT) +#define KVM_REG_RISCV_VECTOR_CSR_REG(name) \ + (offsetof(struct __riscv_v_ext_state, name) / sizeof(unsigned long)) +#define KVM_REG_RISCV_VECTOR_REG(n) \ + ((n) + sizeof(struct __riscv_v_ext_state) / sizeof(unsigned long)) + #endif #endif /* __LINUX_KVM_RISCV_H */ diff --git a/arch/riscv/include/uapi/asm/ptrace.h b/arch/riscv/include/uapi/asm/ptrace.h index 882547f6bd5c..e17c550986a6 100644 --- a/arch/riscv/include/uapi/asm/ptrace.h +++ b/arch/riscv/include/uapi/asm/ptrace.h @@ -71,12 +71,51 @@ struct __riscv_q_ext_state { __u32 reserved[3]; }; +struct __riscv_ctx_hdr { + __u32 magic; + __u32 size; +}; + +struct __riscv_extra_ext_header { + __u32 __padding[129] __attribute__((aligned(16))); + /* + * Reserved for expansion of sigcontext structure. Currently zeroed + * upon signal, and must be zero upon sigreturn. + */ + __u32 reserved; + struct __riscv_ctx_hdr hdr; +}; + union __riscv_fp_state { struct __riscv_f_ext_state f; struct __riscv_d_ext_state d; struct __riscv_q_ext_state q; }; +struct __riscv_v_ext_state { + unsigned long vstart; + unsigned long vl; + unsigned long vtype; + unsigned long vcsr; + void *datap; + /* + * In signal handler, datap will be set a correct user stack offset + * and vector registers will be copied to the address of datap + * pointer. + * + * In ptrace syscall, datap will be set to zero and the vector + * registers will be copied to the address right after this + * structure. + */ +}; + +/* + * According to spec: The number of bits in a single vector register, + * VLEN >= ELEN, which must be a power of 2, and must be no greater than + * 2^16 = 65536bits = 8192bytes + */ +#define RISCV_MAX_VLENB (8192) + #endif /* __ASSEMBLY__ */ #endif /* _UAPI_ASM_RISCV_PTRACE_H */ diff --git a/arch/riscv/include/uapi/asm/sigcontext.h b/arch/riscv/include/uapi/asm/sigcontext.h index 84f2dfcfdbce..8b8a8541673a 100644 --- a/arch/riscv/include/uapi/asm/sigcontext.h +++ b/arch/riscv/include/uapi/asm/sigcontext.h @@ -8,6 +8,17 @@ #include <asm/ptrace.h> +/* The Magic number for signal context frame header. */ +#define RISCV_V_MAGIC 0x53465457 +#define END_MAGIC 0x0 + +/* The size of END signal context header. */ +#define END_HDR_SIZE 0x0 + +struct __sc_riscv_v_state { + struct __riscv_v_ext_state v_state; +} __attribute__((aligned(16))); + /* * Signal context structure * @@ -16,7 +27,10 @@ */ struct sigcontext { struct user_regs_struct sc_regs; - union __riscv_fp_state sc_fpregs; + union { + union __riscv_fp_state sc_fpregs; + struct __riscv_extra_ext_header sc_extdesc; + }; }; #endif /* _UAPI_ASM_RISCV_SIGCONTEXT_H */ diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile index ed5fcd90036e..a42951911067 100644 --- a/arch/riscv/kernel/Makefile +++ b/arch/riscv/kernel/Makefile @@ -56,6 +56,7 @@ obj-$(CONFIG_MMU) += vdso.o vdso/ obj-$(CONFIG_RISCV_M_MODE) += traps_misaligned.o obj-$(CONFIG_FPU) += fpu.o +obj-$(CONFIG_RISCV_ISA_V) += vector.o obj-$(CONFIG_SMP) += smpboot.o obj-$(CONFIG_SMP) += smp.o obj-$(CONFIG_SMP) += cpu_ops.o diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c index e3324d661fb9..de2d16300f69 100644 --- a/arch/riscv/kernel/cpufeature.c +++ b/arch/riscv/kernel/cpufeature.c @@ -21,6 +21,7 @@ #include <asm/hwcap.h> #include <asm/patch.h> #include <asm/processor.h> +#include <asm/vector.h> #define NUM_ALPHA_EXTS ('z' - 'a' + 1) @@ -112,6 +113,7 @@ void __init riscv_fill_hwcap(void) isa2hwcap['f' - 'a'] = COMPAT_HWCAP_ISA_F; isa2hwcap['d' - 'a'] = COMPAT_HWCAP_ISA_D; isa2hwcap['c' - 'a'] = COMPAT_HWCAP_ISA_C; + isa2hwcap['v' - 'a'] = COMPAT_HWCAP_ISA_V; elf_hwcap = 0; @@ -292,6 +294,17 @@ void __init riscv_fill_hwcap(void) elf_hwcap &= ~COMPAT_HWCAP_ISA_F; } + if (elf_hwcap & COMPAT_HWCAP_ISA_V) { + riscv_v_setup_vsize(); + /* + * ISA string in device tree might have 'v' flag, but + * CONFIG_RISCV_ISA_V is disabled in kernel. + * Clear V flag in elf_hwcap if CONFIG_RISCV_ISA_V is disabled. + */ + if (!IS_ENABLED(CONFIG_RISCV_ISA_V)) + elf_hwcap &= ~COMPAT_HWCAP_ISA_V; + } + memset(print_str, 0, sizeof(print_str)); for (i = 0, j = 0; i < NUM_ALPHA_EXTS; i++) if (riscv_isa[0] & BIT_MASK(i)) @@ -305,6 +318,18 @@ void __init riscv_fill_hwcap(void) pr_info("riscv: ELF capabilities %s\n", print_str); } +unsigned long riscv_get_elf_hwcap(void) +{ + unsigned long hwcap; + + hwcap = (elf_hwcap & ((1UL << RISCV_ISA_EXT_BASE) - 1)); + + if (!riscv_v_vstate_ctrl_user_allowed()) + hwcap &= ~COMPAT_HWCAP_ISA_V; + + return hwcap; +} + #ifdef CONFIG_RISCV_ALTERNATIVE /* * Alternative patch sites consider 48 bits when determining when to patch diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S index 3fbb100bc9e4..e9ae284a55c1 100644 --- a/arch/riscv/kernel/entry.S +++ b/arch/riscv/kernel/entry.S @@ -48,10 +48,10 @@ _save_context: * Disable user-mode memory access as it should only be set in the * actual user copy routines. * - * Disable the FPU to detect illegal usage of floating point in kernel - * space. + * Disable the FPU/Vector to detect illegal usage of floating point + * or vector in kernel space. */ - li t0, SR_SUM | SR_FS + li t0, SR_SUM | SR_FS_VS REG_L s0, TASK_TI_USER_SP(tp) csrrc s1, CSR_STATUS, t0 diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S index 4bf6c449d78b..11c3b94c4534 100644 --- a/arch/riscv/kernel/head.S +++ b/arch/riscv/kernel/head.S @@ -140,10 +140,10 @@ secondary_start_sbi: .option pop /* - * Disable FPU to detect illegal usage of - * floating point in kernel space + * Disable FPU & VECTOR to detect illegal usage of + * floating point or vector in kernel space */ - li t0, SR_FS + li t0, SR_FS_VS csrc CSR_STATUS, t0 /* Set trap vector to spin forever to help debug */ @@ -234,10 +234,10 @@ pmp_done: .option pop /* - * Disable FPU to detect illegal usage of - * floating point in kernel space + * Disable FPU & VECTOR to detect illegal usage of + * floating point or vector in kernel space */ - li t0, SR_FS + li t0, SR_FS_VS csrc CSR_STATUS, t0 #ifdef CONFIG_RISCV_BOOT_SPINWAIT @@ -301,6 +301,7 @@ clear_bss_done: la tp, init_task la sp, init_thread_union + THREAD_SIZE XIP_FIXUP_OFFSET sp + addi sp, sp, -PT_SIZE_ON_STACK #ifdef CONFIG_BUILTIN_DTB la a0, __dtb_start XIP_FIXUP_OFFSET a0 @@ -318,6 +319,7 @@ clear_bss_done: /* Restore C environment */ la tp, init_task la sp, init_thread_union + THREAD_SIZE + addi sp, sp, -PT_SIZE_ON_STACK #ifdef CONFIG_KASAN call kasan_early_init @@ -392,7 +394,7 @@ ENTRY(reset_regs) #ifdef CONFIG_FPU csrr t0, CSR_MISA andi t0, t0, (COMPAT_HWCAP_ISA_F | COMPAT_HWCAP_ISA_D) - beqz t0, .Lreset_regs_done + beqz t0, .Lreset_regs_done_fpu li t1, SR_FS csrs CSR_STATUS, t1 @@ -430,8 +432,31 @@ ENTRY(reset_regs) fmv.s.x f31, zero csrw fcsr, 0 /* note that the caller must clear SR_FS */ +.Lreset_regs_done_fpu: #endif /* CONFIG_FPU */ -.Lreset_regs_done: + +#ifdef CONFIG_RISCV_ISA_V + csrr t0, CSR_MISA + li t1, COMPAT_HWCAP_ISA_V + and t0, t0, t1 + beqz t0, .Lreset_regs_done_vector + + /* + * Clear vector registers and reset vcsr + * VLMAX has a defined value, VLEN is a constant, + * and this form of vsetvli is defined to set vl to VLMAX. + */ + li t1, SR_VS + csrs CSR_STATUS, t1 + csrs CSR_VCSR, x0 + vsetvli t1, x0, e8, m8, ta, ma + vmv.v.i v0, 0 + vmv.v.i v8, 0 + vmv.v.i v16, 0 + vmv.v.i v24, 0 + /* note that the caller must clear SR_VS */ +.Lreset_regs_done_vector: +#endif /* CONFIG_RISCV_ISA_V */ ret END(reset_regs) #endif /* CONFIG_RISCV_M_MODE */ diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c index e2a060066730..e32d737e039f 100644 --- a/arch/riscv/kernel/process.c +++ b/arch/riscv/kernel/process.c @@ -24,6 +24,7 @@ #include <asm/switch_to.h> #include <asm/thread_info.h> #include <asm/cpuidle.h> +#include <asm/vector.h> register unsigned long gp_in_global __asm__("gp"); @@ -146,12 +147,29 @@ void flush_thread(void) fstate_off(current, task_pt_regs(current)); memset(¤t->thread.fstate, 0, sizeof(current->thread.fstate)); #endif +#ifdef CONFIG_RISCV_ISA_V + /* Reset vector state */ + riscv_v_vstate_ctrl_init(current); + riscv_v_vstate_off(task_pt_regs(current)); + kfree(current->thread.vstate.datap); + memset(¤t->thread.vstate, 0, sizeof(struct __riscv_v_ext_state)); +#endif +} + +void arch_release_task_struct(struct task_struct *tsk) +{ + /* Free the vector context of datap. */ + if (has_vector()) + kfree(tsk->thread.vstate.datap); } int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) { fstate_save(src, task_pt_regs(src)); *dst = *src; + /* clear entire V context, including datap for a new task */ + memset(&dst->thread.vstate, 0, sizeof(struct __riscv_v_ext_state)); + return 0; } @@ -176,6 +194,8 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) p->thread.s[1] = (unsigned long)args->fn_arg; } else { *childregs = *(current_pt_regs()); + /* Turn off status.VS */ + riscv_v_vstate_off(childregs); if (usp) /* User fork */ childregs->sp = usp; if (clone_flags & CLONE_SETTLS) diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c index 23c48b14a0e7..1d572cf3140f 100644 --- a/arch/riscv/kernel/ptrace.c +++ b/arch/riscv/kernel/ptrace.c @@ -7,6 +7,7 @@ * Copied from arch/tile/kernel/ptrace.c */ +#include <asm/vector.h> #include <asm/ptrace.h> #include <asm/syscall.h> #include <asm/thread_info.h> @@ -24,6 +25,9 @@ enum riscv_regset { #ifdef CONFIG_FPU REGSET_F, #endif +#ifdef CONFIG_RISCV_ISA_V + REGSET_V, +#endif }; static int riscv_gpr_get(struct task_struct *target, @@ -80,6 +84,61 @@ static int riscv_fpr_set(struct task_struct *target, } #endif +#ifdef CONFIG_RISCV_ISA_V +static int riscv_vr_get(struct task_struct *target, + const struct user_regset *regset, + struct membuf to) +{ + struct __riscv_v_ext_state *vstate = &target->thread.vstate; + + if (!riscv_v_vstate_query(task_pt_regs(target))) + return -EINVAL; + + /* + * Ensure the vector registers have been saved to the memory before + * copying them to membuf. + */ + if (target == current) + riscv_v_vstate_save(current, task_pt_regs(current)); + + /* Copy vector header from vstate. */ + membuf_write(&to, vstate, offsetof(struct __riscv_v_ext_state, datap)); + membuf_zero(&to, sizeof(vstate->datap)); + + /* Copy all the vector registers from vstate. */ + return membuf_write(&to, vstate->datap, riscv_v_vsize); +} + +static int riscv_vr_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user *ubuf) +{ + int ret, size; + struct __riscv_v_ext_state *vstate = &target->thread.vstate; + + if (!riscv_v_vstate_query(task_pt_regs(target))) + return -EINVAL; + + /* Copy rest of the vstate except datap */ + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vstate, 0, + offsetof(struct __riscv_v_ext_state, datap)); + if (unlikely(ret)) + return ret; + + /* Skip copy datap. */ + size = sizeof(vstate->datap); + count -= size; + ubuf += size; + + /* Copy all the vector registers. */ + pos = 0; + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vstate->datap, + 0, riscv_v_vsize); + return ret; +} +#endif + static const struct user_regset riscv_user_regset[] = { [REGSET_X] = { .core_note_type = NT_PRSTATUS, @@ -99,6 +158,17 @@ static const struct user_regset riscv_user_regset[] = { .set = riscv_fpr_set, }, #endif +#ifdef CONFIG_RISCV_ISA_V + [REGSET_V] = { + .core_note_type = NT_RISCV_VECTOR, + .align = 16, + .n = ((32 * RISCV_MAX_VLENB) + + sizeof(struct __riscv_v_ext_state)) / sizeof(__u32), + .size = sizeof(__u32), + .regset_get = riscv_vr_get, + .set = riscv_vr_set, + }, +#endif }; static const struct user_regset_view riscv_user_native_view = { diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c index 2ab4cdaa2e68..971fe776e2f8 100644 --- a/arch/riscv/kernel/setup.c +++ b/arch/riscv/kernel/setup.c @@ -264,6 +264,8 @@ static void __init parse_dtb(void) #endif } +extern void __init init_rt_signal_env(void); + void __init setup_arch(char **cmdline_p) { parse_dtb(); @@ -304,6 +306,7 @@ void __init setup_arch(char **cmdline_p) riscv_init_cbo_blocksizes(); riscv_fill_hwcap(); + init_rt_signal_env(); apply_boot_alternatives(); if (IS_ENABLED(CONFIG_RISCV_ISA_ZICBOM) && riscv_isa_extension_available(NULL, ZICBOM)) diff --git a/arch/riscv/kernel/signal.c b/arch/riscv/kernel/signal.c index 9aff9d720590..180d951d3624 100644 --- a/arch/riscv/kernel/signal.c +++ b/arch/riscv/kernel/signal.c @@ -19,10 +19,14 @@ #include <asm/signal.h> #include <asm/signal32.h> #include <asm/switch_to.h> +#include <asm/vector.h> #include <asm/csr.h> #include <asm/cacheflush.h> +unsigned long signal_minsigstksz __ro_after_init; + extern u32 __user_rt_sigreturn[2]; +static size_t riscv_v_sc_size __ro_after_init; #define DEBUG_SIG 0 @@ -40,26 +44,13 @@ static long restore_fp_state(struct pt_regs *regs, { long err; struct __riscv_d_ext_state __user *state = &sc_fpregs->d; - size_t i; err = __copy_from_user(¤t->thread.fstate, state, sizeof(*state)); if (unlikely(err)) return err; fstate_restore(current, regs); - - /* We support no other extension state at this time. */ - for (i = 0; i < ARRAY_SIZE(sc_fpregs->q.reserved); i++) { - u32 value; - - err = __get_user(value, &sc_fpregs->q.reserved[i]); - if (unlikely(err)) - break; - if (value != 0) - return -EINVAL; - } - - return err; + return 0; } static long save_fp_state(struct pt_regs *regs, @@ -67,52 +58,186 @@ static long save_fp_state(struct pt_regs *regs, { long err; struct __riscv_d_ext_state __user *state = &sc_fpregs->d; - size_t i; fstate_save(current, regs); err = __copy_to_user(state, ¤t->thread.fstate, sizeof(*state)); + return err; +} +#else +#define save_fp_state(task, regs) (0) +#define restore_fp_state(task, regs) (0) +#endif + +#ifdef CONFIG_RISCV_ISA_V + +static long save_v_state(struct pt_regs *regs, void __user **sc_vec) +{ + struct __riscv_ctx_hdr __user *hdr; + struct __sc_riscv_v_state __user *state; + void __user *datap; + long err; + + hdr = *sc_vec; + /* Place state to the user's signal context space after the hdr */ + state = (struct __sc_riscv_v_state __user *)(hdr + 1); + /* Point datap right after the end of __sc_riscv_v_state */ + datap = state + 1; + + /* datap is designed to be 16 byte aligned for better performance */ + WARN_ON(unlikely(!IS_ALIGNED((unsigned long)datap, 16))); + + riscv_v_vstate_save(current, regs); + /* Copy everything of vstate but datap. */ + err = __copy_to_user(&state->v_state, ¤t->thread.vstate, + offsetof(struct __riscv_v_ext_state, datap)); + /* Copy the pointer datap itself. */ + err |= __put_user(datap, &state->v_state.datap); + /* Copy the whole vector content to user space datap. */ + err |= __copy_to_user(datap, current->thread.vstate.datap, riscv_v_vsize); + /* Copy magic to the user space after saving all vector conetext */ + err |= __put_user(RISCV_V_MAGIC, &hdr->magic); + err |= __put_user(riscv_v_sc_size, &hdr->size); if (unlikely(err)) return err; - /* We support no other extension state at this time. */ - for (i = 0; i < ARRAY_SIZE(sc_fpregs->q.reserved); i++) { - err = __put_user(0, &sc_fpregs->q.reserved[i]); - if (unlikely(err)) - break; - } + /* Only progress the sv_vec if everything has done successfully */ + *sc_vec += riscv_v_sc_size; + return 0; +} + +/* + * Restore Vector extension context from the user's signal frame. This function + * assumes a valid extension header. So magic and size checking must be done by + * the caller. + */ +static long __restore_v_state(struct pt_regs *regs, void __user *sc_vec) +{ + long err; + struct __sc_riscv_v_state __user *state = sc_vec; + void __user *datap; + + /* Copy everything of __sc_riscv_v_state except datap. */ + err = __copy_from_user(¤t->thread.vstate, &state->v_state, + offsetof(struct __riscv_v_ext_state, datap)); + if (unlikely(err)) + return err; + + /* Copy the pointer datap itself. */ + err = __get_user(datap, &state->v_state.datap); + if (unlikely(err)) + return err; + /* + * Copy the whole vector content from user space datap. Use + * copy_from_user to prevent information leak. + */ + err = copy_from_user(current->thread.vstate.datap, datap, riscv_v_vsize); + if (unlikely(err)) + return err; + + riscv_v_vstate_restore(current, regs); return err; } #else -#define save_fp_state(task, regs) (0) -#define restore_fp_state(task, regs) (0) +#define save_v_state(task, regs) (0) +#define __restore_v_state(task, regs) (0) #endif static long restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) { + void __user *sc_ext_ptr = &sc->sc_extdesc.hdr; + __u32 rsvd; long err; /* sc_regs is structured the same as the start of pt_regs */ err = __copy_from_user(regs, &sc->sc_regs, sizeof(sc->sc_regs)); + if (unlikely(err)) + return err; + /* Restore the floating-point state. */ - if (has_fpu()) - err |= restore_fp_state(regs, &sc->sc_fpregs); + if (has_fpu()) { + err = restore_fp_state(regs, &sc->sc_fpregs); + if (unlikely(err)) + return err; + } + + /* Check the reserved word before extensions parsing */ + err = __get_user(rsvd, &sc->sc_extdesc.reserved); + if (unlikely(err)) + return err; + if (unlikely(rsvd)) + return -EINVAL; + + while (!err) { + __u32 magic, size; + struct __riscv_ctx_hdr __user *head = sc_ext_ptr; + + err |= __get_user(magic, &head->magic); + err |= __get_user(size, &head->size); + if (unlikely(err)) + return err; + + sc_ext_ptr += sizeof(*head); + switch (magic) { + case END_MAGIC: + if (size != END_HDR_SIZE) + return -EINVAL; + + return 0; + case RISCV_V_MAGIC: + if (!has_vector() || !riscv_v_vstate_query(regs) || + size != riscv_v_sc_size) + return -EINVAL; + + err = __restore_v_state(regs, sc_ext_ptr); + break; + default: + return -EINVAL; + } + sc_ext_ptr = (void __user *)head + size; + } return err; } +static size_t get_rt_frame_size(bool cal_all) +{ + struct rt_sigframe __user *frame; + size_t frame_size; + size_t total_context_size = 0; + + frame_size = sizeof(*frame); + + if (has_vector()) { + if (cal_all || riscv_v_vstate_query(task_pt_regs(current))) + total_context_size += riscv_v_sc_size; + } + /* + * Preserved a __riscv_ctx_hdr for END signal context header if an + * extension uses __riscv_extra_ext_header + */ + if (total_context_size) + total_context_size += sizeof(struct __riscv_ctx_hdr); + + frame_size += total_context_size; + + frame_size = round_up(frame_size, 16); + return frame_size; +} + SYSCALL_DEFINE0(rt_sigreturn) { struct pt_regs *regs = current_pt_regs(); struct rt_sigframe __user *frame; struct task_struct *task; sigset_t set; + size_t frame_size = get_rt_frame_size(false); /* Always make any pending restarted system calls return -EINTR */ current->restart_block.fn = do_no_restart_syscall; frame = (struct rt_sigframe __user *)regs->sp; - if (!access_ok(frame, sizeof(*frame))) + if (!access_ok(frame, frame_size)) goto badframe; if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) @@ -146,12 +271,23 @@ static long setup_sigcontext(struct rt_sigframe __user *frame, struct pt_regs *regs) { struct sigcontext __user *sc = &frame->uc.uc_mcontext; + struct __riscv_ctx_hdr __user *sc_ext_ptr = &sc->sc_extdesc.hdr; long err; + /* sc_regs is structured the same as the start of pt_regs */ err = __copy_to_user(&sc->sc_regs, regs, sizeof(sc->sc_regs)); /* Save the floating-point state. */ if (has_fpu()) err |= save_fp_state(regs, &sc->sc_fpregs); + /* Save the vector state. */ + if (has_vector() && riscv_v_vstate_query(regs)) + err |= save_v_state(regs, (void __user **)&sc_ext_ptr); + /* Write zero to fp-reserved space and check it on restore_sigcontext */ + err |= __put_user(0, &sc->sc_extdesc.reserved); + /* And put END __riscv_ctx_hdr at the end. */ + err |= __put_user(END_MAGIC, &sc_ext_ptr->magic); + err |= __put_user(END_HDR_SIZE, &sc_ext_ptr->size); + return err; } @@ -175,6 +311,13 @@ static inline void __user *get_sigframe(struct ksignal *ksig, /* Align the stack frame. */ sp &= ~0xfUL; + /* + * Fail if the size of the altstack is not large enough for the + * sigframe construction. + */ + if (current->sas_ss_size && sp < current->sas_ss_sp) + return (void __user __force *)-1UL; + return (void __user *)sp; } @@ -184,9 +327,10 @@ static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct rt_sigframe __user *frame; long err = 0; unsigned long __maybe_unused addr; + size_t frame_size = get_rt_frame_size(false); - frame = get_sigframe(ksig, regs, sizeof(*frame)); - if (!access_ok(frame, sizeof(*frame))) + frame = get_sigframe(ksig, regs, frame_size); + if (!access_ok(frame, frame_size)) return -EFAULT; err |= copy_siginfo_to_user(&frame->info, &ksig->info); @@ -319,3 +463,23 @@ void arch_do_signal_or_restart(struct pt_regs *regs) */ restore_saved_sigmask(); } + +void init_rt_signal_env(void); +void __init init_rt_signal_env(void) +{ + riscv_v_sc_size = sizeof(struct __riscv_ctx_hdr) + + sizeof(struct __sc_riscv_v_state) + riscv_v_vsize; + /* + * Determine the stack space required for guaranteed signal delivery. + * The signal_minsigstksz will be populated into the AT_MINSIGSTKSZ entry + * in the auxiliary array at process startup. + */ + signal_minsigstksz = get_rt_frame_size(true); +} + +#ifdef CONFIG_DYNAMIC_SIGFRAME +bool sigaltstack_size_valid(size_t ss_size) +{ + return ss_size > get_rt_frame_size(false); +} +#endif /* CONFIG_DYNAMIC_SIGFRAME */ diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c index 67bc5ef3e8b2..6ca2b5309aab 100644 --- a/arch/riscv/kernel/smpboot.c +++ b/arch/riscv/kernel/smpboot.c @@ -32,6 +32,8 @@ #include <asm/tlbflush.h> #include <asm/sections.h> #include <asm/smp.h> +#include <uapi/asm/hwcap.h> +#include <asm/vector.h> #include "head.h" @@ -244,6 +246,11 @@ asmlinkage __visible void smp_callin(void) set_cpu_online(curr_cpuid, 1); probe_vendor_features(curr_cpuid); + if (has_vector()) { + if (riscv_v_setup_vsize()) + elf_hwcap &= ~COMPAT_HWCAP_ISA_V; + } + /* * Remote TLB flushes are ignored while the CPU is offline, so emit * a local TLB flush right now just in case. diff --git a/arch/riscv/kernel/sys_riscv.c b/arch/riscv/kernel/sys_riscv.c index 5db29683ebee..88357a848797 100644 --- a/arch/riscv/kernel/sys_riscv.c +++ b/arch/riscv/kernel/sys_riscv.c @@ -10,6 +10,7 @@ #include <asm/cpufeature.h> #include <asm/hwprobe.h> #include <asm/sbi.h> +#include <asm/vector.h> #include <asm/switch_to.h> #include <asm/uaccess.h> #include <asm/unistd.h> @@ -171,6 +172,9 @@ static void hwprobe_one_pair(struct riscv_hwprobe *pair, if (riscv_isa_extension_available(NULL, c)) pair->value |= RISCV_HWPROBE_IMA_C; + if (has_vector()) + pair->value |= RISCV_HWPROBE_IMA_V; + break; case RISCV_HWPROBE_KEY_CPUPERF_0: diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index 8c258b78c925..05ffdcd1424e 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -26,6 +26,7 @@ #include <asm/ptrace.h> #include <asm/syscall.h> #include <asm/thread_info.h> +#include <asm/vector.h> int show_unhandled_signals = 1; @@ -145,8 +146,29 @@ DO_ERROR_INFO(do_trap_insn_misaligned, SIGBUS, BUS_ADRALN, "instruction address misaligned"); DO_ERROR_INFO(do_trap_insn_fault, SIGSEGV, SEGV_ACCERR, "instruction access fault"); -DO_ERROR_INFO(do_trap_insn_illegal, - SIGILL, ILL_ILLOPC, "illegal instruction"); + +asmlinkage __visible __trap_section void do_trap_insn_illegal(struct pt_regs *regs) +{ + if (user_mode(regs)) { + irqentry_enter_from_user_mode(regs); + + local_irq_enable(); + + if (!riscv_v_first_use_handler(regs)) + do_trap_error(regs, SIGILL, ILL_ILLOPC, regs->epc, + "Oops - illegal instruction"); + + irqentry_exit_to_user_mode(regs); + } else { + irqentry_state_t state = irqentry_nmi_enter(regs); + + do_trap_error(regs, SIGILL, ILL_ILLOPC, regs->epc, + "Oops - illegal instruction"); + + irqentry_nmi_exit(regs, state); + } +} + DO_ERROR_INFO(do_trap_load_fault, SIGSEGV, SEGV_ACCERR, "load access fault"); #ifndef CONFIG_RISCV_M_MODE diff --git a/arch/riscv/kernel/vector.c b/arch/riscv/kernel/vector.c new file mode 100644 index 000000000000..f9c8e19ab301 --- /dev/null +++ b/arch/riscv/kernel/vector.c @@ -0,0 +1,276 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2023 SiFive + * Author: Andy Chiu <andy.chiu@sifive.com> + */ +#include <linux/export.h> +#include <linux/sched/signal.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/sched.h> +#include <linux/uaccess.h> +#include <linux/prctl.h> + +#include <asm/thread_info.h> +#include <asm/processor.h> +#include <asm/insn.h> +#include <asm/vector.h> +#include <asm/csr.h> +#include <asm/elf.h> +#include <asm/ptrace.h> +#include <asm/bug.h> + +static bool riscv_v_implicit_uacc = IS_ENABLED(CONFIG_RISCV_ISA_V_DEFAULT_ENABLE); + +unsigned long riscv_v_vsize __read_mostly; +EXPORT_SYMBOL_GPL(riscv_v_vsize); + +int riscv_v_setup_vsize(void) +{ + unsigned long this_vsize; + + /* There are 32 vector registers with vlenb length. */ + riscv_v_enable(); + this_vsize = csr_read(CSR_VLENB) * 32; + riscv_v_disable(); + + if (!riscv_v_vsize) { + riscv_v_vsize = this_vsize; + return 0; + } + + if (riscv_v_vsize != this_vsize) { + WARN(1, "RISCV_ISA_V only supports one vlenb on SMP systems"); + return -EOPNOTSUPP; + } + + return 0; +} + +static bool insn_is_vector(u32 insn_buf) +{ + u32 opcode = insn_buf & __INSN_OPCODE_MASK; + u32 width, csr; + + /* + * All V-related instructions, including CSR operations are 4-Byte. So, + * do not handle if the instruction length is not 4-Byte. + */ + if (unlikely(GET_INSN_LENGTH(insn_buf) != 4)) + return false; + + switch (opcode) { + case RVV_OPCODE_VECTOR: + return true; + case RVV_OPCODE_VL: + case RVV_OPCODE_VS: + width = RVV_EXRACT_VL_VS_WIDTH(insn_buf); + if (width == RVV_VL_VS_WIDTH_8 || width == RVV_VL_VS_WIDTH_16 || + width == RVV_VL_VS_WIDTH_32 || width == RVV_VL_VS_WIDTH_64) + return true; + + break; + case RVG_OPCODE_SYSTEM: + csr = RVG_EXTRACT_SYSTEM_CSR(insn_buf); + if ((csr >= CSR_VSTART && csr <= CSR_VCSR) || + (csr >= CSR_VL && csr <= CSR_VLENB)) + return true; + } + + return false; +} + +static int riscv_v_thread_zalloc(void) +{ + void *datap; + + datap = kzalloc(riscv_v_vsize, GFP_KERNEL); + if (!datap) + return -ENOMEM; + + current->thread.vstate.datap = datap; + memset(¤t->thread.vstate, 0, offsetof(struct __riscv_v_ext_state, + datap)); + return 0; +} + +#define VSTATE_CTRL_GET_CUR(x) ((x) & PR_RISCV_V_VSTATE_CTRL_CUR_MASK) +#define VSTATE_CTRL_GET_NEXT(x) (((x) & PR_RISCV_V_VSTATE_CTRL_NEXT_MASK) >> 2) +#define VSTATE_CTRL_MAKE_NEXT(x) (((x) << 2) & PR_RISCV_V_VSTATE_CTRL_NEXT_MASK) +#define VSTATE_CTRL_GET_INHERIT(x) (!!((x) & PR_RISCV_V_VSTATE_CTRL_INHERIT)) +static inline int riscv_v_ctrl_get_cur(struct task_struct *tsk) +{ + return VSTATE_CTRL_GET_CUR(tsk->thread.vstate_ctrl); +} + +static inline int riscv_v_ctrl_get_next(struct task_struct *tsk) +{ + return VSTATE_CTRL_GET_NEXT(tsk->thread.vstate_ctrl); +} + +static inline bool riscv_v_ctrl_test_inherit(struct task_struct *tsk) +{ + return VSTATE_CTRL_GET_INHERIT(tsk->thread.vstate_ctrl); +} + +static inline void riscv_v_ctrl_set(struct task_struct *tsk, int cur, int nxt, + bool inherit) +{ + unsigned long ctrl; + + ctrl = cur & PR_RISCV_V_VSTATE_CTRL_CUR_MASK; + ctrl |= VSTATE_CTRL_MAKE_NEXT(nxt); + if (inherit) + ctrl |= PR_RISCV_V_VSTATE_CTRL_INHERIT; + tsk->thread.vstate_ctrl = ctrl; +} + +bool riscv_v_vstate_ctrl_user_allowed(void) +{ + return riscv_v_ctrl_get_cur(current) == PR_RISCV_V_VSTATE_CTRL_ON; +} +EXPORT_SYMBOL_GPL(riscv_v_vstate_ctrl_user_allowed); + +bool riscv_v_first_use_handler(struct pt_regs *regs) +{ + u32 __user *epc = (u32 __user *)regs->epc; + u32 insn = (u32)regs->badaddr; + + /* Do not handle if V is not supported, or disabled */ + if (!(ELF_HWCAP & COMPAT_HWCAP_ISA_V)) + return false; + + /* If V has been enabled then it is not the first-use trap */ + if (riscv_v_vstate_query(regs)) + return false; + + /* Get the instruction */ + if (!insn) { + if (__get_user(insn, epc)) + return false; + } + + /* Filter out non-V instructions */ + if (!insn_is_vector(insn)) + return false; + + /* Sanity check. datap should be null by the time of the first-use trap */ + WARN_ON(current->thread.vstate.datap); + + /* + * Now we sure that this is a V instruction. And it executes in the + * context where VS has been off. So, try to allocate the user's V + * context and resume execution. + */ + if (riscv_v_thread_zalloc()) { + force_sig(SIGBUS); + return true; + } + riscv_v_vstate_on(regs); + return true; +} + +void riscv_v_vstate_ctrl_init(struct task_struct *tsk) +{ + bool inherit; + int cur, next; + + if (!has_vector()) + return; + + next = riscv_v_ctrl_get_next(tsk); + if (!next) { + if (READ_ONCE(riscv_v_implicit_uacc)) + cur = PR_RISCV_V_VSTATE_CTRL_ON; + else + cur = PR_RISCV_V_VSTATE_CTRL_OFF; + } else { + cur = next; + } + /* Clear next mask if inherit-bit is not set */ + inherit = riscv_v_ctrl_test_inherit(tsk); + if (!inherit) + next = PR_RISCV_V_VSTATE_CTRL_DEFAULT; + + riscv_v_ctrl_set(tsk, cur, next, inherit); +} + +long riscv_v_vstate_ctrl_get_current(void) +{ + if (!has_vector()) + return -EINVAL; + + return current->thread.vstate_ctrl & PR_RISCV_V_VSTATE_CTRL_MASK; +} + +long riscv_v_vstate_ctrl_set_current(unsigned long arg) +{ + bool inherit; + int cur, next; + + if (!has_vector()) + return -EINVAL; + + if (arg & ~PR_RISCV_V_VSTATE_CTRL_MASK) + return -EINVAL; + + cur = VSTATE_CTRL_GET_CUR(arg); + switch (cur) { + case PR_RISCV_V_VSTATE_CTRL_OFF: + /* Do not allow user to turn off V if current is not off */ + if (riscv_v_ctrl_get_cur(current) != PR_RISCV_V_VSTATE_CTRL_OFF) + return -EPERM; + + break; + case PR_RISCV_V_VSTATE_CTRL_ON: + break; + case PR_RISCV_V_VSTATE_CTRL_DEFAULT: + cur = riscv_v_ctrl_get_cur(current); + break; + default: + return -EINVAL; + } + + next = VSTATE_CTRL_GET_NEXT(arg); + inherit = VSTATE_CTRL_GET_INHERIT(arg); + switch (next) { + case PR_RISCV_V_VSTATE_CTRL_DEFAULT: + case PR_RISCV_V_VSTATE_CTRL_OFF: + case PR_RISCV_V_VSTATE_CTRL_ON: + riscv_v_ctrl_set(current, cur, next, inherit); + return 0; + } + + return -EINVAL; +} + +#ifdef CONFIG_SYSCTL + +static struct ctl_table riscv_v_default_vstate_table[] = { + { + .procname = "riscv_v_default_allow", + .data = &riscv_v_implicit_uacc, + .maxlen = sizeof(riscv_v_implicit_uacc), + .mode = 0644, + .proc_handler = proc_dobool, + }, + { } +}; + +static int __init riscv_v_sysctl_init(void) +{ + if (has_vector()) + if (!register_sysctl("abi", riscv_v_default_vstate_table)) + return -EINVAL; + return 0; +} + +#else /* ! CONFIG_SYSCTL */ +static int __init riscv_v_sysctl_init(void) { return 0; } +#endif /* ! CONFIG_SYSCTL */ + +static int riscv_v_init(void) +{ + return riscv_v_sysctl_init(); +} +core_initcall(riscv_v_init); diff --git a/arch/riscv/kvm/Makefile b/arch/riscv/kvm/Makefile index 8031b8912a0d..7b4c21f9aa6a 100644 --- a/arch/riscv/kvm/Makefile +++ b/arch/riscv/kvm/Makefile @@ -17,6 +17,7 @@ kvm-y += mmu.o kvm-y += vcpu.o kvm-y += vcpu_exit.o kvm-y += vcpu_fp.o +kvm-y += vcpu_vector.o kvm-y += vcpu_insn.o kvm-y += vcpu_switch.o kvm-y += vcpu_sbi.o diff --git a/arch/riscv/kvm/vcpu.c b/arch/riscv/kvm/vcpu.c index 8bd9f2a8a0b9..de24127e7e93 100644 --- a/arch/riscv/kvm/vcpu.c +++ b/arch/riscv/kvm/vcpu.c @@ -22,6 +22,8 @@ #include <asm/cacheflush.h> #include <asm/hwcap.h> #include <asm/sbi.h> +#include <asm/vector.h> +#include <asm/kvm_vcpu_vector.h> const struct _kvm_stats_desc kvm_vcpu_stats_desc[] = { KVM_GENERIC_VCPU_STATS(), @@ -57,6 +59,7 @@ static const unsigned long kvm_isa_ext_arr[] = { [KVM_RISCV_ISA_EXT_H] = RISCV_ISA_EXT_h, [KVM_RISCV_ISA_EXT_I] = RISCV_ISA_EXT_i, [KVM_RISCV_ISA_EXT_M] = RISCV_ISA_EXT_m, + [KVM_RISCV_ISA_EXT_V] = RISCV_ISA_EXT_v, KVM_ISA_EXT_ARR(SSAIA), KVM_ISA_EXT_ARR(SSTC), @@ -85,6 +88,8 @@ static bool kvm_riscv_vcpu_isa_enable_allowed(unsigned long ext) switch (ext) { case KVM_RISCV_ISA_EXT_H: return false; + case KVM_RISCV_ISA_EXT_V: + return riscv_v_vstate_ctrl_user_allowed(); default: break; } @@ -138,6 +143,8 @@ static void kvm_riscv_reset_vcpu(struct kvm_vcpu *vcpu) kvm_riscv_vcpu_fp_reset(vcpu); + kvm_riscv_vcpu_vector_reset(vcpu); + kvm_riscv_vcpu_timer_reset(vcpu); kvm_riscv_vcpu_aia_reset(vcpu); @@ -198,6 +205,9 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu) cntx->hstatus |= HSTATUS_SPVP; cntx->hstatus |= HSTATUS_SPV; + if (kvm_riscv_vcpu_alloc_vector_context(vcpu, cntx)) + return -ENOMEM; + /* By default, make CY, TM, and IR counters accessible in VU mode */ reset_csr->scounteren = 0x7; @@ -241,6 +251,9 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) /* Free unused pages pre-allocated for G-stage page table mappings */ kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); + + /* Free vector context space for host and guest kernel */ + kvm_riscv_vcpu_free_vector_context(vcpu); } int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) @@ -679,6 +692,9 @@ static int kvm_riscv_vcpu_set_reg(struct kvm_vcpu *vcpu, return kvm_riscv_vcpu_set_reg_isa_ext(vcpu, reg); case KVM_REG_RISCV_SBI_EXT: return kvm_riscv_vcpu_set_reg_sbi_ext(vcpu, reg); + case KVM_REG_RISCV_VECTOR: + return kvm_riscv_vcpu_set_reg_vector(vcpu, reg, + KVM_REG_RISCV_VECTOR); default: break; } @@ -708,6 +724,9 @@ static int kvm_riscv_vcpu_get_reg(struct kvm_vcpu *vcpu, return kvm_riscv_vcpu_get_reg_isa_ext(vcpu, reg); case KVM_REG_RISCV_SBI_EXT: return kvm_riscv_vcpu_get_reg_sbi_ext(vcpu, reg); + case KVM_REG_RISCV_VECTOR: + return kvm_riscv_vcpu_get_reg_vector(vcpu, reg, + KVM_REG_RISCV_VECTOR); default: break; } @@ -1002,6 +1021,9 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) kvm_riscv_vcpu_host_fp_save(&vcpu->arch.host_context); kvm_riscv_vcpu_guest_fp_restore(&vcpu->arch.guest_context, vcpu->arch.isa); + kvm_riscv_vcpu_host_vector_save(&vcpu->arch.host_context); + kvm_riscv_vcpu_guest_vector_restore(&vcpu->arch.guest_context, + vcpu->arch.isa); kvm_riscv_vcpu_aia_load(vcpu, cpu); @@ -1021,6 +1043,9 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) kvm_riscv_vcpu_host_fp_restore(&vcpu->arch.host_context); kvm_riscv_vcpu_timer_save(vcpu); + kvm_riscv_vcpu_guest_vector_save(&vcpu->arch.guest_context, + vcpu->arch.isa); + kvm_riscv_vcpu_host_vector_restore(&vcpu->arch.host_context); csr->vsstatus = csr_read(CSR_VSSTATUS); csr->vsie = csr_read(CSR_VSIE); diff --git a/arch/riscv/kvm/vcpu_vector.c b/arch/riscv/kvm/vcpu_vector.c new file mode 100644 index 000000000000..edd2eecbddc2 --- /dev/null +++ b/arch/riscv/kvm/vcpu_vector.c @@ -0,0 +1,186 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2022 SiFive + * + * Authors: + * Vincent Chen <vincent.chen@sifive.com> + * Greentime Hu <greentime.hu@sifive.com> + */ + +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/kvm_host.h> +#include <linux/uaccess.h> +#include <asm/hwcap.h> +#include <asm/kvm_vcpu_vector.h> +#include <asm/vector.h> + +#ifdef CONFIG_RISCV_ISA_V +void kvm_riscv_vcpu_vector_reset(struct kvm_vcpu *vcpu) +{ + unsigned long *isa = vcpu->arch.isa; + struct kvm_cpu_context *cntx = &vcpu->arch.guest_context; + + cntx->sstatus &= ~SR_VS; + if (riscv_isa_extension_available(isa, v)) { + cntx->sstatus |= SR_VS_INITIAL; + WARN_ON(!cntx->vector.datap); + memset(cntx->vector.datap, 0, riscv_v_vsize); + } else { + cntx->sstatus |= SR_VS_OFF; + } +} + +static void kvm_riscv_vcpu_vector_clean(struct kvm_cpu_context *cntx) +{ + cntx->sstatus &= ~SR_VS; + cntx->sstatus |= SR_VS_CLEAN; +} + +void kvm_riscv_vcpu_guest_vector_save(struct kvm_cpu_context *cntx, + unsigned long *isa) +{ + if ((cntx->sstatus & SR_VS) == SR_VS_DIRTY) { + if (riscv_isa_extension_available(isa, v)) + __kvm_riscv_vector_save(cntx); + kvm_riscv_vcpu_vector_clean(cntx); + } +} + +void kvm_riscv_vcpu_guest_vector_restore(struct kvm_cpu_context *cntx, + unsigned long *isa) +{ + if ((cntx->sstatus & SR_VS) != SR_VS_OFF) { + if (riscv_isa_extension_available(isa, v)) + __kvm_riscv_vector_restore(cntx); + kvm_riscv_vcpu_vector_clean(cntx); + } +} + +void kvm_riscv_vcpu_host_vector_save(struct kvm_cpu_context *cntx) +{ + /* No need to check host sstatus as it can be modified outside */ + if (riscv_isa_extension_available(NULL, v)) + __kvm_riscv_vector_save(cntx); +} + +void kvm_riscv_vcpu_host_vector_restore(struct kvm_cpu_context *cntx) +{ + if (riscv_isa_extension_available(NULL, v)) + __kvm_riscv_vector_restore(cntx); +} + +int kvm_riscv_vcpu_alloc_vector_context(struct kvm_vcpu *vcpu, + struct kvm_cpu_context *cntx) +{ + cntx->vector.datap = kmalloc(riscv_v_vsize, GFP_KERNEL); + if (!cntx->vector.datap) + return -ENOMEM; + + vcpu->arch.host_context.vector.datap = kzalloc(riscv_v_vsize, GFP_KERNEL); + if (!vcpu->arch.host_context.vector.datap) + return -ENOMEM; + + return 0; +} + +void kvm_riscv_vcpu_free_vector_context(struct kvm_vcpu *vcpu) +{ + kfree(vcpu->arch.guest_reset_context.vector.datap); + kfree(vcpu->arch.host_context.vector.datap); +} +#endif + +static void *kvm_riscv_vcpu_vreg_addr(struct kvm_vcpu *vcpu, + unsigned long reg_num, + size_t reg_size) +{ + struct kvm_cpu_context *cntx = &vcpu->arch.guest_context; + void *reg_val; + size_t vlenb = riscv_v_vsize / 32; + + if (reg_num < KVM_REG_RISCV_VECTOR_REG(0)) { + if (reg_size != sizeof(unsigned long)) + return NULL; + switch (reg_num) { + case KVM_REG_RISCV_VECTOR_CSR_REG(vstart): + reg_val = &cntx->vector.vstart; + break; + case KVM_REG_RISCV_VECTOR_CSR_REG(vl): + reg_val = &cntx->vector.vl; + break; + case KVM_REG_RISCV_VECTOR_CSR_REG(vtype): + reg_val = &cntx->vector.vtype; + break; + case KVM_REG_RISCV_VECTOR_CSR_REG(vcsr): + reg_val = &cntx->vector.vcsr; + break; + case KVM_REG_RISCV_VECTOR_CSR_REG(datap): + default: + return NULL; + } + } else if (reg_num <= KVM_REG_RISCV_VECTOR_REG(31)) { + if (reg_size != vlenb) + return NULL; + reg_val = cntx->vector.datap + + (reg_num - KVM_REG_RISCV_VECTOR_REG(0)) * vlenb; + } else { + return NULL; + } + + return reg_val; +} + +int kvm_riscv_vcpu_get_reg_vector(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg, + unsigned long rtype) +{ + unsigned long *isa = vcpu->arch.isa; + unsigned long __user *uaddr = + (unsigned long __user *)(unsigned long)reg->addr; + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | + KVM_REG_SIZE_MASK | + rtype); + void *reg_val = NULL; + size_t reg_size = KVM_REG_SIZE(reg->id); + + if (rtype == KVM_REG_RISCV_VECTOR && + riscv_isa_extension_available(isa, v)) { + reg_val = kvm_riscv_vcpu_vreg_addr(vcpu, reg_num, reg_size); + } + + if (!reg_val) + return -EINVAL; + + if (copy_to_user(uaddr, reg_val, reg_size)) + return -EFAULT; + + return 0; +} + +int kvm_riscv_vcpu_set_reg_vector(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg, + unsigned long rtype) +{ + unsigned long *isa = vcpu->arch.isa; + unsigned long __user *uaddr = + (unsigned long __user *)(unsigned long)reg->addr; + unsigned long reg_num = reg->id & ~(KVM_REG_ARCH_MASK | + KVM_REG_SIZE_MASK | + rtype); + void *reg_val = NULL; + size_t reg_size = KVM_REG_SIZE(reg->id); + + if (rtype == KVM_REG_RISCV_VECTOR && + riscv_isa_extension_available(isa, v)) { + reg_val = kvm_riscv_vcpu_vreg_addr(vcpu, reg_num, reg_size); + } + + if (!reg_val) + return -EINVAL; + + if (copy_from_user(reg_val, uaddr, reg_size)) + return -EFAULT; + + return 0; +} diff --git a/include/uapi/linux/elf.h b/include/uapi/linux/elf.h index ac3da855fb19..7d8d9ae36615 100644 --- a/include/uapi/linux/elf.h +++ b/include/uapi/linux/elf.h @@ -440,6 +440,7 @@ typedef struct elf64_shdr { #define NT_MIPS_DSP 0x800 /* MIPS DSP ASE registers */ #define NT_MIPS_FP_MODE 0x801 /* MIPS floating-point mode */ #define NT_MIPS_MSA 0x802 /* MIPS SIMD registers */ +#define NT_RISCV_VECTOR 0x900 /* RISC-V vector registers */ #define NT_LOONGARCH_CPUCFG 0xa00 /* LoongArch CPU config registers */ #define NT_LOONGARCH_CSR 0xa01 /* LoongArch control and status registers */ #define NT_LOONGARCH_LSX 0xa02 /* LoongArch Loongson SIMD Extension registers */ diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h index f23d9a16507f..3c36aeade991 100644 --- a/include/uapi/linux/prctl.h +++ b/include/uapi/linux/prctl.h @@ -294,4 +294,15 @@ struct prctl_mm_map { #define PR_SET_MEMORY_MERGE 67 #define PR_GET_MEMORY_MERGE 68 + +#define PR_RISCV_V_SET_CONTROL 69 +#define PR_RISCV_V_GET_CONTROL 70 +# define PR_RISCV_V_VSTATE_CTRL_DEFAULT 0 +# define PR_RISCV_V_VSTATE_CTRL_OFF 1 +# define PR_RISCV_V_VSTATE_CTRL_ON 2 +# define PR_RISCV_V_VSTATE_CTRL_INHERIT (1 << 4) +# define PR_RISCV_V_VSTATE_CTRL_CUR_MASK 0x3 +# define PR_RISCV_V_VSTATE_CTRL_NEXT_MASK 0xc +# define PR_RISCV_V_VSTATE_CTRL_MASK 0x1f + #endif /* _LINUX_PRCTL_H */ diff --git a/kernel/sys.c b/kernel/sys.c index 339fee3eff6a..05f838929e72 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -140,6 +140,12 @@ #ifndef GET_TAGGED_ADDR_CTRL # define GET_TAGGED_ADDR_CTRL() (-EINVAL) #endif +#ifndef RISCV_V_SET_CONTROL +# define RISCV_V_SET_CONTROL(a) (-EINVAL) +#endif +#ifndef RISCV_V_GET_CONTROL +# define RISCV_V_GET_CONTROL() (-EINVAL) +#endif /* * this is where the system-wide overflow UID and GID are defined, for @@ -2708,6 +2714,12 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, error = !!test_bit(MMF_VM_MERGE_ANY, &me->mm->flags); break; #endif + case PR_RISCV_V_SET_CONTROL: + error = RISCV_V_SET_CONTROL(arg2); + break; + case PR_RISCV_V_GET_CONTROL: + error = RISCV_V_GET_CONTROL(); + break; default: error = -EINVAL; break; diff --git a/tools/testing/selftests/riscv/Makefile b/tools/testing/selftests/riscv/Makefile index 32a72902d045..9dd629cc86aa 100644 --- a/tools/testing/selftests/riscv/Makefile +++ b/tools/testing/selftests/riscv/Makefile @@ -5,7 +5,7 @@ ARCH ?= $(shell uname -m 2>/dev/null || echo not) ifneq (,$(filter $(ARCH),riscv)) -RISCV_SUBTARGETS ?= hwprobe +RISCV_SUBTARGETS ?= hwprobe vector else RISCV_SUBTARGETS := endif diff --git a/tools/testing/selftests/riscv/hwprobe/.gitignore b/tools/testing/selftests/riscv/hwprobe/.gitignore new file mode 100644 index 000000000000..8113dc3bdd03 --- /dev/null +++ b/tools/testing/selftests/riscv/hwprobe/.gitignore @@ -0,0 +1 @@ +hwprobe diff --git a/tools/testing/selftests/riscv/vector/.gitignore b/tools/testing/selftests/riscv/vector/.gitignore new file mode 100644 index 000000000000..4f2b4e8a3b08 --- /dev/null +++ b/tools/testing/selftests/riscv/vector/.gitignore @@ -0,0 +1,2 @@ +vstate_exec_nolibc +vstate_prctl diff --git a/tools/testing/selftests/riscv/vector/Makefile b/tools/testing/selftests/riscv/vector/Makefile new file mode 100644 index 000000000000..cd6e80bf995d --- /dev/null +++ b/tools/testing/selftests/riscv/vector/Makefile @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2021 ARM Limited +# Originally tools/testing/arm64/abi/Makefile + +TEST_GEN_PROGS := vstate_prctl +TEST_GEN_PROGS_EXTENDED := vstate_exec_nolibc + +include ../../lib.mk + +$(OUTPUT)/vstate_prctl: vstate_prctl.c ../hwprobe/sys_hwprobe.S + $(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^ + +$(OUTPUT)/vstate_exec_nolibc: vstate_exec_nolibc.c + $(CC) -nostdlib -static -include ../../../../include/nolibc/nolibc.h \ + -Wall $(CFLAGS) $(LDFLAGS) $^ -o $@ -lgcc diff --git a/tools/testing/selftests/riscv/vector/vstate_exec_nolibc.c b/tools/testing/selftests/riscv/vector/vstate_exec_nolibc.c new file mode 100644 index 000000000000..5cbc392944a6 --- /dev/null +++ b/tools/testing/selftests/riscv/vector/vstate_exec_nolibc.c @@ -0,0 +1,111 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <sys/prctl.h> + +#define THIS_PROGRAM "./vstate_exec_nolibc" + +int main(int argc, char **argv) +{ + int rc, pid, status, test_inherit = 0; + long ctrl, ctrl_c; + char *exec_argv[2], *exec_envp[2]; + + if (argc > 1) + test_inherit = 1; + + ctrl = my_syscall1(__NR_prctl, PR_RISCV_V_GET_CONTROL); + if (ctrl < 0) { + puts("PR_RISCV_V_GET_CONTROL is not supported\n"); + return ctrl; + } + + if (test_inherit) { + pid = fork(); + if (pid == -1) { + puts("fork failed\n"); + exit(-1); + } + + /* child */ + if (!pid) { + exec_argv[0] = THIS_PROGRAM; + exec_argv[1] = NULL; + exec_envp[0] = NULL; + exec_envp[1] = NULL; + /* launch the program again to check inherit */ + rc = execve(THIS_PROGRAM, exec_argv, exec_envp); + if (rc) { + puts("child execve failed\n"); + exit(-1); + } + } + + } else { + pid = fork(); + if (pid == -1) { + puts("fork failed\n"); + exit(-1); + } + + if (!pid) { + rc = my_syscall1(__NR_prctl, PR_RISCV_V_GET_CONTROL); + if (rc != ctrl) { + puts("child's vstate_ctrl not equal to parent's\n"); + exit(-1); + } + asm volatile (".option push\n\t" + ".option arch, +v\n\t" + "vsetvli x0, x0, e32, m8, ta, ma\n\t" + ".option pop\n\t" + ); + exit(ctrl); + } + } + + rc = waitpid(-1, &status, 0); + + if (WIFEXITED(status) && WEXITSTATUS(status) == -1) { + puts("child exited abnormally\n"); + exit(-1); + } + + if (WIFSIGNALED(status)) { + if (WTERMSIG(status) != SIGILL) { + puts("child was terminated by unexpected signal\n"); + exit(-1); + } + + if ((ctrl & PR_RISCV_V_VSTATE_CTRL_CUR_MASK) != PR_RISCV_V_VSTATE_CTRL_OFF) { + puts("child signaled by illegal V access but vstate_ctrl is not off\n"); + exit(-1); + } + + /* child terminated, and its vstate_ctrl is off */ + exit(ctrl); + } + + ctrl_c = WEXITSTATUS(status); + if (test_inherit) { + if (ctrl & PR_RISCV_V_VSTATE_CTRL_INHERIT) { + if (!(ctrl_c & PR_RISCV_V_VSTATE_CTRL_INHERIT)) { + puts("parent has inherit bit, but child has not\n"); + exit(-1); + } + } + rc = (ctrl & PR_RISCV_V_VSTATE_CTRL_NEXT_MASK) >> 2; + if (rc != PR_RISCV_V_VSTATE_CTRL_DEFAULT) { + if (rc != (ctrl_c & PR_RISCV_V_VSTATE_CTRL_CUR_MASK)) { + puts("parent's next setting does not equal to child's\n"); + exit(-1); + } + + if (!(ctrl & PR_RISCV_V_VSTATE_CTRL_INHERIT)) { + if ((ctrl_c & PR_RISCV_V_VSTATE_CTRL_NEXT_MASK) != + PR_RISCV_V_VSTATE_CTRL_DEFAULT) { + puts("must clear child's next vstate_ctrl if !inherit\n"); + exit(-1); + } + } + } + } + return ctrl; +} diff --git a/tools/testing/selftests/riscv/vector/vstate_prctl.c b/tools/testing/selftests/riscv/vector/vstate_prctl.c new file mode 100644 index 000000000000..b348b475be57 --- /dev/null +++ b/tools/testing/selftests/riscv/vector/vstate_prctl.c @@ -0,0 +1,189 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <sys/prctl.h> +#include <unistd.h> +#include <asm/hwprobe.h> +#include <errno.h> +#include <sys/wait.h> + +#include "../../kselftest.h" + +/* + * Rather than relying on having a new enough libc to define this, just do it + * ourselves. This way we don't need to be coupled to a new-enough libc to + * contain the call. + */ +long riscv_hwprobe(struct riscv_hwprobe *pairs, size_t pair_count, + size_t cpu_count, unsigned long *cpus, unsigned int flags); + +#define NEXT_PROGRAM "./vstate_exec_nolibc" +static int launch_test(int test_inherit) +{ + char *exec_argv[3], *exec_envp[1]; + int rc, pid, status; + + pid = fork(); + if (pid < 0) { + ksft_test_result_fail("fork failed %d", pid); + return -1; + } + + if (!pid) { + exec_argv[0] = NEXT_PROGRAM; + exec_argv[1] = test_inherit != 0 ? "x" : NULL; + exec_argv[2] = NULL; + exec_envp[0] = NULL; + /* launch the program again to check inherit */ + rc = execve(NEXT_PROGRAM, exec_argv, exec_envp); + if (rc) { + perror("execve"); + ksft_test_result_fail("child execve failed %d\n", rc); + exit(-1); + } + } + + rc = waitpid(-1, &status, 0); + if (rc < 0) { + ksft_test_result_fail("waitpid failed\n"); + return -3; + } + + if ((WIFEXITED(status) && WEXITSTATUS(status) == -1) || + WIFSIGNALED(status)) { + ksft_test_result_fail("child exited abnormally\n"); + return -4; + } + + return WEXITSTATUS(status); +} + +int test_and_compare_child(long provided, long expected, int inherit) +{ + int rc; + + rc = prctl(PR_RISCV_V_SET_CONTROL, provided); + if (rc != 0) { + ksft_test_result_fail("prctl with provided arg %lx failed with code %d\n", + provided, rc); + return -1; + } + rc = launch_test(inherit); + if (rc != expected) { + ksft_test_result_fail("Test failed, check %d != %d\n", rc, + expected); + return -2; + } + return 0; +} + +#define PR_RISCV_V_VSTATE_CTRL_CUR_SHIFT 0 +#define PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT 2 + +int main(void) +{ + struct riscv_hwprobe pair; + long flag, expected; + long rc; + + pair.key = RISCV_HWPROBE_KEY_IMA_EXT_0; + rc = riscv_hwprobe(&pair, 1, 0, NULL, 0); + if (rc < 0) { + ksft_test_result_fail("hwprobe() failed with %d\n", rc); + return -1; + } + + if (pair.key != RISCV_HWPROBE_KEY_IMA_EXT_0) { + ksft_test_result_fail("hwprobe cannot probe RISCV_HWPROBE_KEY_IMA_EXT_0\n"); + return -2; + } + + if (!(pair.value & RISCV_HWPROBE_IMA_V)) { + rc = prctl(PR_RISCV_V_GET_CONTROL); + if (rc != -1 || errno != EINVAL) { + ksft_test_result_fail("GET_CONTROL should fail on kernel/hw without V\n"); + return -3; + } + + rc = prctl(PR_RISCV_V_SET_CONTROL, PR_RISCV_V_VSTATE_CTRL_ON); + if (rc != -1 || errno != EINVAL) { + ksft_test_result_fail("GET_CONTROL should fail on kernel/hw without V\n"); + return -4; + } + + ksft_test_result_skip("Vector not supported\n"); + return 0; + } + + flag = PR_RISCV_V_VSTATE_CTRL_ON; + rc = prctl(PR_RISCV_V_SET_CONTROL, flag); + if (rc != 0) { + ksft_test_result_fail("Enabling V for current should always success\n"); + return -5; + } + + flag = PR_RISCV_V_VSTATE_CTRL_OFF; + rc = prctl(PR_RISCV_V_SET_CONTROL, flag); + if (rc != -1 || errno != EPERM) { + ksft_test_result_fail("Disabling current's V alive must fail with EPERM(%d)\n", + errno); + return -5; + } + + /* Turn on next's vector explicitly and test */ + flag = PR_RISCV_V_VSTATE_CTRL_ON << PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT; + if (test_and_compare_child(flag, PR_RISCV_V_VSTATE_CTRL_ON, 0)) + return -6; + + /* Turn off next's vector explicitly and test */ + flag = PR_RISCV_V_VSTATE_CTRL_OFF << PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT; + if (test_and_compare_child(flag, PR_RISCV_V_VSTATE_CTRL_OFF, 0)) + return -7; + + /* Turn on next's vector explicitly and test inherit */ + flag = PR_RISCV_V_VSTATE_CTRL_ON << PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT; + flag |= PR_RISCV_V_VSTATE_CTRL_INHERIT; + expected = flag | PR_RISCV_V_VSTATE_CTRL_ON; + if (test_and_compare_child(flag, expected, 0)) + return -8; + + if (test_and_compare_child(flag, expected, 1)) + return -9; + + /* Turn off next's vector explicitly and test inherit */ + flag = PR_RISCV_V_VSTATE_CTRL_OFF << PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT; + flag |= PR_RISCV_V_VSTATE_CTRL_INHERIT; + expected = flag | PR_RISCV_V_VSTATE_CTRL_OFF; + if (test_and_compare_child(flag, expected, 0)) + return -10; + + if (test_and_compare_child(flag, expected, 1)) + return -11; + + /* arguments should fail with EINVAL */ + rc = prctl(PR_RISCV_V_SET_CONTROL, 0xff0); + if (rc != -1 || errno != EINVAL) { + ksft_test_result_fail("Undefined control argument should return EINVAL\n"); + return -12; + } + + rc = prctl(PR_RISCV_V_SET_CONTROL, 0x3); + if (rc != -1 || errno != EINVAL) { + ksft_test_result_fail("Undefined control argument should return EINVAL\n"); + return -12; + } + + rc = prctl(PR_RISCV_V_SET_CONTROL, 0xc); + if (rc != -1 || errno != EINVAL) { + ksft_test_result_fail("Undefined control argument should return EINVAL\n"); + return -12; + } + + rc = prctl(PR_RISCV_V_SET_CONTROL, 0xc); + if (rc != -1 || errno != EINVAL) { + ksft_test_result_fail("Undefined control argument should return EINVAL\n"); + return -12; + } + + ksft_test_result_pass("tests for riscv_v_vstate_ctrl pass\n"); + ksft_exit_pass(); + return 0; +} |