Files
kernel-zhihe-a210/arch/riscv/kernel/ptrace.c
2025-11-19 21:14:48 +08:00

636 lines
16 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright 2010 Tilera Corporation. All Rights Reserved.
* Copyright 2015 Regents of the University of California
* Copyright 2017 SiFive
*
* Copied from arch/tile/kernel/ptrace.c
*/
#include <asm/vector.h>
#include <asm/ptrace.h>
#include <asm/syscall.h>
#include <asm/thread_info.h>
#include <asm/switch_to.h>
#include <linux/audit.h>
#include <linux/compat.h>
#include <linux/ptrace.h>
#include <linux/elf.h>
#include <linux/regset.h>
#include <linux/sched.h>
#include <linux/sched/task_stack.h>
#include <linux/hw_breakpoint.h>
enum riscv_regset {
REGSET_X,
#ifdef CONFIG_FPU
REGSET_F,
#endif
#ifdef CONFIG_RISCV_ISA_V
REGSET_V,
#endif
#ifdef CONFIG_HAVE_HW_BREAKPOINT
REGSET_HW_BREAK,
REGSET_HW_WATCH,
#endif
};
static int riscv_gpr_get(struct task_struct *target,
const struct user_regset *regset,
struct membuf to)
{
return membuf_write(&to, task_pt_regs(target),
sizeof(struct user_regs_struct));
}
static int riscv_gpr_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
struct pt_regs *regs;
regs = task_pt_regs(target);
return user_regset_copyin(&pos, &count, &kbuf, &ubuf, regs, 0, -1);
}
#ifdef CONFIG_FPU
static int riscv_fpr_get(struct task_struct *target,
const struct user_regset *regset,
struct membuf to)
{
struct __riscv_d_ext_state *fstate = &target->thread.fstate;
if (target == current)
fstate_save(current, task_pt_regs(current));
membuf_write(&to, fstate, offsetof(struct __riscv_d_ext_state, fcsr));
membuf_store(&to, fstate->fcsr);
return membuf_zero(&to, 4); // explicitly pad
}
static int riscv_fpr_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_d_ext_state *fstate = &target->thread.fstate;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, fstate, 0,
offsetof(struct __riscv_d_ext_state, fcsr));
if (!ret) {
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, fstate, 0,
offsetof(struct __riscv_d_ext_state, fcsr) +
sizeof(fstate->fcsr));
}
return ret;
}
#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;
struct __riscv_v_regset_state ptrace_vstate;
if (!riscv_v_vstate_query(task_pt_regs(target))) {
if (riscv_v_thread_zalloc(target))
return -EINVAL;
riscv_v_vstate_on(task_pt_regs(target));
if (target == current)
riscv_v_vstate_restore(current, task_pt_regs(current));
}
/*
* 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));
ptrace_vstate.vstart = vstate->vstart;
ptrace_vstate.vl = vstate->vl;
ptrace_vstate.vtype = vstate->vtype;
ptrace_vstate.vcsr = vstate->vcsr;
ptrace_vstate.vlenb = vstate->vlenb;
/* Copy vector header from vstate. */
membuf_write(&to, &ptrace_vstate, sizeof(struct __riscv_v_regset_state));
/* 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;
struct __riscv_v_ext_state *vstate = &target->thread.vstate;
struct __riscv_v_regset_state ptrace_vstate;
if (!riscv_v_vstate_query(task_pt_regs(target))) {
if (riscv_v_thread_zalloc(target))
return -EINVAL;
riscv_v_vstate_on(task_pt_regs(target));
if (target == current)
riscv_v_vstate_restore(current, task_pt_regs(current));
}
/* Copy rest of the vstate except datap */
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ptrace_vstate, 0,
sizeof(struct __riscv_v_regset_state));
if (unlikely(ret))
return ret;
if (vstate->vlenb != ptrace_vstate.vlenb)
return -EINVAL;
vstate->vstart = ptrace_vstate.vstart;
vstate->vl = ptrace_vstate.vl;
vstate->vtype = ptrace_vstate.vtype;
vstate->vcsr = ptrace_vstate.vcsr;
/* Copy all the vector registers. */
pos = 0;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vstate->datap,
0, riscv_v_vsize);
return ret;
}
#endif
#ifdef CONFIG_HAVE_HW_BREAKPOINT
static void ptrace_hbptriggered(struct perf_event *bp,
struct perf_sample_data *data,
struct pt_regs *regs)
{
struct arch_hw_breakpoint *bkpt = counter_arch_bp(bp);
force_sig_fault(SIGTRAP, TRAP_HWBKPT, (void __user *)bkpt->addr);
}
static int hw_break_get(struct task_struct *target,
const struct user_regset *regset,
struct membuf to)
{
/* send total number of h/w debug triggers */
struct user_hwdebug_state hw_state;
hw_state.dbg_slots = hw_breakpoint_slots(regset->core_note_type);
membuf_write(&to, &hw_state, sizeof(hw_state));
return 0;
}
static inline int hw_break_empty(u64 addr, u64 type, u64 len)
{
/* TODO: for now adjusted to current riscv-gdb behavior */
return (!addr && !len);
}
static int hw_break_cache_trigger(struct task_struct *target, u32 note_type,
u64 addr, u64 type, u64 len, u32 idx)
{
struct arch_hw_breakpoint *bp;
u64 bp_type;
u64 bp_len;
// pr_info("%s:[%d] note_type=%d addr=%llx type=%lld len=%lld\n", __func__, idx, note_type, addr, type, len);
if (!hw_break_empty(addr, type, len)) {
/* bp len: gdb to kernel */
switch (len) {
case 2:
bp_len = HW_BREAKPOINT_LEN_2;
break;
case 4:
bp_len = HW_BREAKPOINT_LEN_4;
break;
case 8:
bp_len = HW_BREAKPOINT_LEN_8;
break;
default:
pr_warn("%s: unsupported len: %llu\n", __func__, len);
return -EINVAL;
}
/* bp type: gdb to kernel */
switch (type) {
case 0:
bp_type = HW_BREAKPOINT_X;
break;
case 1:
bp_type = HW_BREAKPOINT_R;
break;
case 2:
bp_type = HW_BREAKPOINT_W;
break;
case 3:
bp_type = HW_BREAKPOINT_RW;
break;
default:
pr_warn("%s: unsupported type: %llu\n", __func__, type);
return -EINVAL;
}
}
if (note_type == NT_RISCV_HW_BREAK)
bp = &(target->thread.hbp_break[idx]);
if (note_type == NT_RISCV_HW_WATCH)
bp = &(target->thread.hbp_watch[idx]);
bp->addr = addr;
bp->type = bp_type;
bp->len = bp_len;
return 0;
}
static int hw_break_register_trigger(struct task_struct *target, u32 note_type,
u64 addr, u64 type, u64 len, u32 idx)
{
struct perf_event *bp = ERR_PTR(-EINVAL);
struct perf_event_attr attr;
// pr_info("%s:[%d] note_type=%d addr=%llx type=%lld len=%lld\n", __func__, idx, note_type, addr, type, len);
bp = target->thread.ptrace_bps[idx];
if (bp) {
attr = bp->attr;
if (hw_break_empty(addr, type, len)) {
attr.disabled = 1;
} else {
attr.bp_addr = addr;
attr.bp_type = type;
attr.bp_len = len;
attr.disabled = 0;
}
return modify_user_hw_breakpoint(bp, &attr);
}
ptrace_breakpoint_init(&attr);
attr.bp_addr = addr;
attr.bp_type = type;
attr.bp_len = len;
bp = register_user_hw_breakpoint(&attr, ptrace_hbptriggered,
NULL, target);
if (IS_ERR(bp)) {
pr_err("%s failed! ret=%ld\n", __func__, PTR_ERR(bp));
return PTR_ERR(bp);
}
target->thread.ptrace_bps[idx] = bp;
return 0;
}
static int hw_break_setup_trigger(struct task_struct *target)
{
u32 i, idx = 0;
flush_ptrace_hw_breakpoint(target);
for (i = 0; i < HW_BP_NUM_MAX; i++) {
if (target->thread.hbp_break[i].addr) {
hw_break_register_trigger(target, NT_RISCV_HW_BREAK, target->thread.hbp_break[i].addr, target->thread.hbp_break[i].type, target->thread.hbp_break[i].len, idx);
idx++;
}
}
for (i = 0; i < HW_BP_NUM_MAX; i++) {
if (target->thread.hbp_watch[i].addr) {
hw_break_register_trigger(target, NT_RISCV_HW_WATCH, target->thread.hbp_watch[i].addr, target->thread.hbp_watch[i].type, target->thread.hbp_watch[i].len, idx);
idx++;
}
}
return idx;
}
static int hw_break_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, idx = 0, offset, limit, note_type;
u64 addr;
u64 type;
u64 size;
#define PTRACE_HBP_ADDR_SZ sizeof(u64)
#define PTRACE_HBP_TYPE_SZ sizeof(u64)
#define PTRACE_HBP_SIZE_SZ sizeof(u64)
note_type = regset->core_note_type; // NT_RISCV_HW_BREAK(0x904) | NT_RISCV_HW_WATCH(0x905)
/* Resource info and pad */
offset = offsetof(struct user_hwdebug_state, dbg_regs);
user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, offset);
// pr_info("%s: core_note_type=%d count=%d offset=%d regset.n=%d regset.size=%d\n", __func__, regset->core_note_type, count, offset, regset->n, regset->size);
/* trigger settings */
limit = regset->n * regset->size;
while (count && offset < limit) {
if (count <= PTRACE_HBP_ADDR_SZ)
return -EINVAL;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &addr,
offset, offset + PTRACE_HBP_ADDR_SZ);
if (ret)
return ret;
offset += PTRACE_HBP_ADDR_SZ;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &type,
offset, offset + PTRACE_HBP_TYPE_SZ);
if (ret)
return ret;
offset += PTRACE_HBP_TYPE_SZ;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &size,
offset, offset + PTRACE_HBP_SIZE_SZ);
if (ret)
return ret;
offset += PTRACE_HBP_SIZE_SZ;
ret = hw_break_cache_trigger(target, note_type, addr, type, size, idx);
if (ret)
return ret;
idx++;
}
// pr_info("%s: count=%d offset=%d\n", __func__, count, offset);
hw_break_setup_trigger(target);
return 0;
}
#endif
static const struct user_regset riscv_user_regset[] = {
[REGSET_X] = {
.core_note_type = NT_PRSTATUS,
.n = ELF_NGREG,
.size = sizeof(elf_greg_t),
.align = sizeof(elf_greg_t),
.regset_get = riscv_gpr_get,
.set = riscv_gpr_set,
},
#ifdef CONFIG_FPU
[REGSET_F] = {
.core_note_type = NT_PRFPREG,
.n = ELF_NFPREG,
.size = sizeof(elf_fpreg_t),
.align = sizeof(elf_fpreg_t),
.regset_get = riscv_fpr_get,
.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_regset_state)) / sizeof(__u32),
.size = sizeof(__u32),
.regset_get = riscv_vr_get,
.set = riscv_vr_set,
},
#endif
#ifdef CONFIG_HAVE_HW_BREAKPOINT
[REGSET_HW_BREAK] = {
.core_note_type = NT_RISCV_HW_BREAK,
.n = sizeof(struct user_hwdebug_state) / sizeof(u32),
.size = sizeof(u32),
.align = sizeof(u32),
.regset_get = hw_break_get,
.set = hw_break_set,
},
[REGSET_HW_WATCH] = {
.core_note_type = NT_RISCV_HW_WATCH,
.n = sizeof(struct user_hwdebug_state) / sizeof(u32),
.size = sizeof(u32),
.align = sizeof(u32),
.regset_get = hw_break_get,
.set = hw_break_set,
},
#endif
};
static const struct user_regset_view riscv_user_native_view = {
.name = "riscv",
.e_machine = EM_RISCV,
.regsets = riscv_user_regset,
.n = ARRAY_SIZE(riscv_user_regset),
};
struct pt_regs_offset {
const char *name;
int offset;
};
#define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
#define REG_OFFSET_END {.name = NULL, .offset = 0}
static const struct pt_regs_offset regoffset_table[] = {
REG_OFFSET_NAME(epc),
REG_OFFSET_NAME(ra),
REG_OFFSET_NAME(sp),
REG_OFFSET_NAME(gp),
REG_OFFSET_NAME(tp),
REG_OFFSET_NAME(t0),
REG_OFFSET_NAME(t1),
REG_OFFSET_NAME(t2),
REG_OFFSET_NAME(s0),
REG_OFFSET_NAME(s1),
REG_OFFSET_NAME(a0),
REG_OFFSET_NAME(a1),
REG_OFFSET_NAME(a2),
REG_OFFSET_NAME(a3),
REG_OFFSET_NAME(a4),
REG_OFFSET_NAME(a5),
REG_OFFSET_NAME(a6),
REG_OFFSET_NAME(a7),
REG_OFFSET_NAME(s2),
REG_OFFSET_NAME(s3),
REG_OFFSET_NAME(s4),
REG_OFFSET_NAME(s5),
REG_OFFSET_NAME(s6),
REG_OFFSET_NAME(s7),
REG_OFFSET_NAME(s8),
REG_OFFSET_NAME(s9),
REG_OFFSET_NAME(s10),
REG_OFFSET_NAME(s11),
REG_OFFSET_NAME(t3),
REG_OFFSET_NAME(t4),
REG_OFFSET_NAME(t5),
REG_OFFSET_NAME(t6),
REG_OFFSET_NAME(status),
REG_OFFSET_NAME(badaddr),
REG_OFFSET_NAME(cause),
REG_OFFSET_NAME(orig_a0),
REG_OFFSET_END,
};
/**
* regs_query_register_offset() - query register offset from its name
* @name: the name of a register
*
* regs_query_register_offset() returns the offset of a register in struct
* pt_regs from its name. If the name is invalid, this returns -EINVAL;
*/
int regs_query_register_offset(const char *name)
{
const struct pt_regs_offset *roff;
for (roff = regoffset_table; roff->name != NULL; roff++)
if (!strcmp(roff->name, name))
return roff->offset;
return -EINVAL;
}
/**
* regs_within_kernel_stack() - check the address in the stack
* @regs: pt_regs which contains kernel stack pointer.
* @addr: address which is checked.
*
* regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
* If @addr is within the kernel stack, it returns true. If not, returns false.
*/
static bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr)
{
return (addr & ~(THREAD_SIZE - 1)) ==
(kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1));
}
/**
* regs_get_kernel_stack_nth() - get Nth entry of the stack
* @regs: pt_regs which contains kernel stack pointer.
* @n: stack entry number.
*
* regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
* is specified by @regs. If the @n th entry is NOT in the kernel stack,
* this returns 0.
*/
unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
{
unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs);
addr += n;
if (regs_within_kernel_stack(regs, (unsigned long)addr))
return *addr;
else
return 0;
}
void ptrace_disable(struct task_struct *child)
{
}
long arch_ptrace(struct task_struct *child, long request,
unsigned long addr, unsigned long data)
{
long ret = -EIO;
switch (request) {
default:
ret = ptrace_request(child, request, addr, data);
break;
}
return ret;
}
#if IS_ENABLED(CONFIG_COMPAT) || IS_ENABLED(CONFIG_ARCH_RV64ILP32)
static int compat_riscv_gpr_get(struct task_struct *target,
const struct user_regset *regset,
struct membuf to)
{
struct compat_user_regs_struct cregs;
regs_to_cregs(&cregs, task_pt_regs(target));
return membuf_write(&to, &cregs,
sizeof(struct compat_user_regs_struct));
}
static int compat_riscv_gpr_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 compat_user_regs_struct cregs;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &cregs, 0, -1);
cregs_to_regs(&cregs, task_pt_regs(target));
return ret;
}
static const struct user_regset compat_riscv_user_regset[] = {
[REGSET_X] = {
.core_note_type = NT_PRSTATUS,
.n = ELF_NGREG,
.size = sizeof(compat_elf_greg_t),
.align = sizeof(compat_elf_greg_t),
.regset_get = compat_riscv_gpr_get,
.set = compat_riscv_gpr_set,
},
#ifdef CONFIG_FPU
[REGSET_F] = {
.core_note_type = NT_PRFPREG,
.n = ELF_NFPREG,
.size = sizeof(elf_fpreg_t),
.align = sizeof(elf_fpreg_t),
.regset_get = riscv_fpr_get,
.set = riscv_fpr_set,
},
#endif
};
static const struct user_regset_view compat_riscv_user_native_view = {
.name = "riscv",
.e_machine = EM_RISCV,
.regsets = compat_riscv_user_regset,
.n = ARRAY_SIZE(compat_riscv_user_regset),
};
#endif
#ifdef CONFIG_COMPAT
long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
compat_ulong_t caddr, compat_ulong_t cdata)
{
long ret = -EIO;
switch (request) {
default:
ret = compat_ptrace_request(child, request, caddr, cdata);
break;
}
return ret;
}
#endif /* CONFIG_COMPAT */
const struct user_regset_view *task_user_regset_view(struct task_struct *task)
{
#if IS_ENABLED(CONFIG_COMPAT) || IS_ENABLED(CONFIG_ARCH_RV64ILP32)
if (test_tsk_thread_flag(task, TIF_32BIT) &&
!test_tsk_thread_flag(task, TIF_64ILP32))
return &compat_riscv_user_native_view;
else
#endif
return &riscv_user_native_view;
}