[RFC PATCH V3 10/11] riscv: Add ptrace support

From: guoren
Date: Sun Mar 08 2020 - 05:53:50 EST


From: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>

Add new regset for vector and the implementation is similar to
fpu.

Signed-off-by: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>
---
arch/riscv/include/uapi/asm/elf.h | 1 +
arch/riscv/kernel/ptrace.c | 41 +++++++++++++++++++++++++++++++
include/uapi/linux/elf.h | 1 +
3 files changed, 43 insertions(+)

diff --git a/arch/riscv/include/uapi/asm/elf.h b/arch/riscv/include/uapi/asm/elf.h
index d696d6610231..099434d075a7 100644
--- a/arch/riscv/include/uapi/asm/elf.h
+++ b/arch/riscv/include/uapi/asm/elf.h
@@ -23,6 +23,7 @@ typedef struct user_regs_struct elf_gregset_t;
typedef __u64 elf_fpreg_t;
typedef union __riscv_fp_state elf_fpregset_t;
#define ELF_NFPREG (sizeof(struct __riscv_d_ext_state) / sizeof(elf_fpreg_t))
+#define ELF_NVREG (sizeof(struct __riscv_v_state) / sizeof(elf_greg_t))

#if __riscv_xlen == 64
#define ELF_RISCV_R_SYM(r_info) ELF64_R_SYM(r_info)
diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c
index 407464201b91..0e3c3543476c 100644
--- a/arch/riscv/kernel/ptrace.c
+++ b/arch/riscv/kernel/ptrace.c
@@ -26,6 +26,9 @@ enum riscv_regset {
#ifdef CONFIG_FPU
REGSET_F,
#endif
+#ifdef CONFIG_VECTOR
+ REGSET_V,
+#endif
};

static int riscv_gpr_get(struct task_struct *target,
@@ -92,6 +95,34 @@ static int riscv_fpr_set(struct task_struct *target,
}
#endif

+#ifdef CONFIG_VECTOR
+static int riscv_vr_get(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ void *kbuf, void __user *ubuf)
+{
+ int ret;
+ struct __riscv_v_state *vstate = &target->thread.vstate;
+
+ ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, vstate, 0,
+ offsetof(struct __riscv_v_state, vtype));
+ return ret;
+}
+
+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;
+ struct __riscv_v_state *vstate = &target->thread.vstate;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vstate, 0,
+ offsetof(struct __riscv_v_state, vtype));
+ return ret;
+}
+#endif
+
static const struct user_regset riscv_user_regset[] = {
[REGSET_X] = {
.core_note_type = NT_PRSTATUS,
@@ -111,6 +142,16 @@ static const struct user_regset riscv_user_regset[] = {
.set = &riscv_fpr_set,
},
#endif
+#ifdef CONFIG_VECTOR
+ [REGSET_V] = {
+ .core_note_type = NT_RISCV_VECTOR,
+ .n = ELF_NVREG,
+ .size = sizeof(elf_greg_t),
+ .align = sizeof(elf_greg_t),
+ .get = &riscv_vr_get,
+ .set = &riscv_vr_set,
+ },
+#endif
};

static const struct user_regset_view riscv_user_native_view = {
diff --git a/include/uapi/linux/elf.h b/include/uapi/linux/elf.h
index 34c02e4290fe..e428f9e8710a 100644
--- a/include/uapi/linux/elf.h
+++ b/include/uapi/linux/elf.h
@@ -428,6 +428,7 @@ 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 */

/* Note header in a PT_NOTE section */
typedef struct elf32_note {
--
2.17.0