xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

csky: Implement ptrace regs and stack API

Browse Source 
Needed for kprobes support. Copied and adapted from Patrick's patch,
but it has been modified for csky's pt_regs.

ref:
https://lore.kernel.org/linux-riscv/1572919114-3886-2-git-send-email-vincent.chen@sifive.com/raw

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Patrick Staehlin <me@packi.ch>
This commit is contained in:
Guo Ren
2019-12-17 14:57:22 +08:00
committed by Guo Ren
parent 12879bda3c
commit bfe47f358a
3 changed files with 145 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

103
arch/csky/kernel/ptrace.c
View File

@@ -193,6 +193,109 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task)
return &user_csky_view;
}
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(tls),
REG_OFFSET_NAME(lr),
REG_OFFSET_NAME(pc),
REG_OFFSET_NAME(sr),
REG_OFFSET_NAME(usp),
REG_OFFSET_NAME(orig_a0),
REG_OFFSET_NAME(a0),
REG_OFFSET_NAME(a1),
REG_OFFSET_NAME(a2),
REG_OFFSET_NAME(a3),
REG_OFFSET_NAME(regs[0]),
REG_OFFSET_NAME(regs[1]),
REG_OFFSET_NAME(regs[2]),
REG_OFFSET_NAME(regs[3]),
REG_OFFSET_NAME(regs[4]),
REG_OFFSET_NAME(regs[5]),
REG_OFFSET_NAME(regs[6]),
REG_OFFSET_NAME(regs[7]),
REG_OFFSET_NAME(regs[8]),
REG_OFFSET_NAME(regs[9]),
#if defined(__CSKYABIV2__)
REG_OFFSET_NAME(exregs[0]),
REG_OFFSET_NAME(exregs[1]),
REG_OFFSET_NAME(exregs[2]),
REG_OFFSET_NAME(exregs[3]),
REG_OFFSET_NAME(exregs[4]),
REG_OFFSET_NAME(exregs[5]),
REG_OFFSET_NAME(exregs[6]),
REG_OFFSET_NAME(exregs[7]),
REG_OFFSET_NAME(exregs[8]),
REG_OFFSET_NAME(exregs[9]),
REG_OFFSET_NAME(exregs[10]),
REG_OFFSET_NAME(exregs[11]),
REG_OFFSET_NAME(exregs[12]),
REG_OFFSET_NAME(exregs[13]),
REG_OFFSET_NAME(exregs[14]),
REG_OFFSET_NAME(rhi),
REG_OFFSET_NAME(rlo),
REG_OFFSET_NAME(dcsr),
#endif
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)
{
singlestep_disable(child);