Commit ea1afe33 authored by Sven Schnelle's avatar Sven Schnelle Committed by Helge Deller
Browse files

parisc: add functions required by KPROBE_EVENTS 



implement regs_get_register(), regs_get_kernel_stack_nth() and
regs_within_kernel_stack()

Signed-off-by: default avatarSven Schnelle <svens@stackframe.org>
Signed-off-by: default avatarHelge Deller <deller@gmx.de>
parent 82d96bf6

arch/parisc/include/asm/ptrace.h

+13 −0
Original line number Diff line number Diff line
@@ -37,4 +37,17 @@ extern int regs_query_register_offset(const char *name); 
extern const char *regs_query_register_name(unsigned int offset);

#define MAX_REG_OFFSET (offsetof(struct pt_regs, ipsw))



#define kernel_stack_pointer(regs) ((regs)->gr[30])



static inline unsigned long regs_get_register(struct pt_regs *regs,

					      unsigned int offset)

{

	if (unlikely(offset > MAX_REG_OFFSET))

		return 0;

	return *(unsigned long *)((unsigned long)regs + offset);

}



unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n);

int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr);



#endif

arch/parisc/kernel/ptrace.c

+35 −0
Original line number Diff line number Diff line
@@ -789,3 +789,38 @@ const char *regs_query_register_name(unsigned int offset) 
			return roff->name;

	return NULL;

}



/**

 * 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.

 */

int 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 0;



	return *addr;

}