[linux-block.git] / arch / s390 / kernel / rethook.c

// SPDX-License-Identifier: GPL-2.0-or-later
#include <linux/rethook.h>
#include <linux/kprobes.h>
#include "rethook.h"

void arch_rethook_prepare(struct rethook_node *rh, struct pt_regs *regs, bool mcount)
{
	rh->ret_addr = regs->gprs[14];
	rh->frame = regs->gprs[15];

	/* Replace the return addr with trampoline addr */
	regs->gprs[14] = (unsigned long)&arch_rethook_trampoline;
}
NOKPROBE_SYMBOL(arch_rethook_prepare);

void arch_rethook_fixup_return(struct pt_regs *regs,
			       unsigned long correct_ret_addr)
{
	/* Replace fake return address with real one. */
	regs->gprs[14] = correct_ret_addr;
}
NOKPROBE_SYMBOL(arch_rethook_fixup_return);

/*
 * Called from arch_rethook_trampoline
 */
unsigned long arch_rethook_trampoline_callback(struct pt_regs *regs)
{
	return rethook_trampoline_handler(regs, regs->gprs[15]);
}
NOKPROBE_SYMBOL(arch_rethook_trampoline_callback);

/* assembler function that handles the rethook must not be probed itself */
NOKPROBE_SYMBOL(arch_rethook_trampoline);
Commit	Line	Data
	1	// SPDX-License-Identifier: GPL-2.0-or-later
	2	#include <linux/rethook.h>
	3	#include <linux/kprobes.h>
	4	#include "rethook.h"
	5
	6	void arch_rethook_prepare(struct rethook_node rh, struct pt_regs regs, bool mcount)
	7	{
	8	rh->ret_addr = regs->gprs[14];
	9	rh->frame = regs->gprs[15];
	10
	11	/* Replace the return addr with trampoline addr */
	12	regs->gprs[14] = (unsigned long)&arch_rethook_trampoline;
	13	}
	14	NOKPROBE_SYMBOL(arch_rethook_prepare);
	15
	16	void arch_rethook_fixup_return(struct pt_regs *regs,
	17	unsigned long correct_ret_addr)
	18	{
	19	/* Replace fake return address with real one. */
	20	regs->gprs[14] = correct_ret_addr;
	21	}
	22	NOKPROBE_SYMBOL(arch_rethook_fixup_return);
	23
	24	/*
	25	* Called from arch_rethook_trampoline
	26	*/
	27	unsigned long arch_rethook_trampoline_callback(struct pt_regs *regs)
	28	{
	29	return rethook_trampoline_handler(regs, regs->gprs[15]);
	30	}
	31	NOKPROBE_SYMBOL(arch_rethook_trampoline_callback);
	32
	33	/* assembler function that handles the rethook must not be probed itself */
	34	NOKPROBE_SYMBOL(arch_rethook_trampoline);