Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * Jump label s390 support
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  * Copyright IBM Corp. 2011
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  * Author(s): Jan Glauber <jang@linux.vnet.ibm.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) #include <linux/uaccess.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) #include <linux/stop_machine.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/jump_label.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <asm/ipl.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) struct insn {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) 	u16 opcode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) 	s32 offset;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) } __packed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) static void jump_label_make_nop(struct jump_entry *entry, struct insn *insn)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 	/* brcl 0,offset */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 	insn->opcode = 0xc004;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 	insn->offset = (jump_entry_target(entry) - jump_entry_code(entry)) >> 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) static void jump_label_make_branch(struct jump_entry *entry, struct insn *insn)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 	/* brcl 15,offset */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 	insn->opcode = 0xc0f4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 	insn->offset = (jump_entry_target(entry) - jump_entry_code(entry)) >> 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) static void jump_label_bug(struct jump_entry *entry, struct insn *expected,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 			   struct insn *new)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 	unsigned char *ipc = (unsigned char *)jump_entry_code(entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 	unsigned char *ipe = (unsigned char *)expected;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 	unsigned char *ipn = (unsigned char *)new;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 	pr_emerg("Jump label code mismatch at %pS [%px]\n", ipc, ipc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 	pr_emerg("Found:    %6ph\n", ipc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 	pr_emerg("Expected: %6ph\n", ipe);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 	pr_emerg("New:      %6ph\n", ipn);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 	panic("Corrupted kernel text");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) static struct insn orignop = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 	.opcode = 0xc004,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 	.offset = JUMP_LABEL_NOP_OFFSET >> 1,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) static void __jump_label_transform(struct jump_entry *entry,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 				   enum jump_label_type type,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 				   int init)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 	void *code = (void *)jump_entry_code(entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 	struct insn old, new;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 	if (type == JUMP_LABEL_JMP) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 		jump_label_make_nop(entry, &old);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 		jump_label_make_branch(entry, &new);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 		jump_label_make_branch(entry, &old);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 		jump_label_make_nop(entry, &new);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 	if (init) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 		if (memcmp(code, &orignop, sizeof(orignop)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 			jump_label_bug(entry, &orignop, &new);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) 		if (memcmp(code, &old, sizeof(old)))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 			jump_label_bug(entry, &old, &new);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) 	s390_kernel_write(code, &new, sizeof(new));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) static void __jump_label_sync(void *dummy)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) void arch_jump_label_transform(struct jump_entry *entry,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) 			       enum jump_label_type type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) 	__jump_label_transform(entry, type, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) 	smp_call_function(__jump_label_sync, NULL, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) void arch_jump_label_transform_static(struct jump_entry *entry,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) 				      enum jump_label_type type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) 	__jump_label_transform(entry, type, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) }