powerpc/signal: Use PPC_RAW_xx() macros

To improve readability, use PPC_RAW_xx() macros instead of
open coding. Those macros are self-explanatory so the comments
can go as well.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4ca2bfdca2f47a293d05f61eb3c4e487ee170f1f.1621506159.git.christophe.leroy@csgroup.eu

arch/powerpc/include/asm/ppc-opcode.h

@@ -275,7 +275,6 @@
 #define PPC_INST_MFSPR_DSCR_USER_MASK	0xfc1ffffe
 #define PPC_INST_MTSPR_DSCR_USER	0x7c0303a6
 #define PPC_INST_MTSPR_DSCR_USER_MASK	0xfc1ffffe
-#define PPC_INST_SC			0x44000002
 #define PPC_INST_STRING			0x7c00042a
 #define PPC_INST_STRING_MASK		0xfc0007fe
 #define PPC_INST_STRING_GEN_MASK	0xfc00067e
@@ -294,7 +293,6 @@
 #define PPC_INST_ADD			0x7c000214
 #define PPC_INST_BLR			0x4e800020
 #define PPC_INST_BCTR			0x4e800420
-#define PPC_INST_BCTRL			0x4e800421
 #define PPC_INST_DIVD			0x7c0003d2
 #define PPC_INST_RLDICR			0x78000004
 #define PPC_INST_ORI			0x60000000
@@ -418,6 +416,8 @@
 #define PPC_RAW_STBCIX(s, a, b)		(0x7c0007aa | __PPC_RS(s) | __PPC_RA(a) | __PPC_RB(b))
 #define PPC_RAW_DCBFPS(a, b)		(0x7c0000ac | ___PPC_RA(a) | ___PPC_RB(b) | (4 << 21))
 #define PPC_RAW_DCBSTPS(a, b)		(0x7c0000ac | ___PPC_RA(a) | ___PPC_RB(b) | (6 << 21))
+#define PPC_RAW_SC()			(0x44000002)
+
 /*
  * Define what the VSX XX1 form instructions will look like, then add
  * the 128 bit load store instructions based on that.
@@ -486,6 +486,7 @@
 #define PPC_RAW_MTLR(r)			(0x7c0803a6 | ___PPC_RT(r))
 #define PPC_RAW_MFLR(t)			(PPC_INST_MFLR | ___PPC_RT(t))
 #define PPC_RAW_BCTR()			(PPC_INST_BCTR)
+#define PPC_RAW_BCTRL()			(0x4e800421)
 #define PPC_RAW_MTCTR(r)		(PPC_INST_MTCTR | ___PPC_RT(r))
 #define PPC_RAW_ADDI(d, a, i)		(PPC_INST_ADDI | ___PPC_RT(d) | ___PPC_RA(a) | IMM_L(i))
 #define PPC_RAW_LI(r, i)		PPC_RAW_ADDI(r, 0, i)

arch/powerpc/kernel/signal_32.c

@@ -828,10 +828,8 @@ int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset,
 		tramp = VDSO32_SYMBOL(tsk->mm->context.vdso, sigtramp_rt32);
 	} else {
 		tramp = (unsigned long)mctx->mc_pad;
-		/* Set up the sigreturn trampoline: li r0,sigret; sc */
-		unsafe_put_user(PPC_INST_ADDI + __NR_rt_sigreturn, &mctx->mc_pad[0],
-				failed);
-		unsafe_put_user(PPC_INST_SC, &mctx->mc_pad[1], failed);
+		unsafe_put_user(PPC_RAW_LI(_R0, __NR_rt_sigreturn), &mctx->mc_pad[0], failed);
+		unsafe_put_user(PPC_RAW_SC(), &mctx->mc_pad[1], failed);
 		asm("dcbst %y0; sync; icbi %y0; sync" :: "Z" (mctx->mc_pad[0]));
 	}
 	unsafe_put_sigset_t(&frame->uc.uc_sigmask, oldset, failed);
@@ -926,9 +924,8 @@ int handle_signal32(struct ksignal *ksig, sigset_t *oldset,
 		tramp = VDSO32_SYMBOL(tsk->mm->context.vdso, sigtramp32);
 	} else {
 		tramp = (unsigned long)mctx->mc_pad;
-		/* Set up the sigreturn trampoline: li r0,sigret; sc */
-		unsafe_put_user(PPC_INST_ADDI + __NR_sigreturn, &mctx->mc_pad[0], failed);
-		unsafe_put_user(PPC_INST_SC, &mctx->mc_pad[1], failed);
+		unsafe_put_user(PPC_RAW_LI(_R0, __NR_sigreturn), &mctx->mc_pad[0], failed);
+		unsafe_put_user(PPC_RAW_SC(), &mctx->mc_pad[1], failed);
 		asm("dcbst %y0; sync; icbi %y0; sync" :: "Z" (mctx->mc_pad[0]));
 	}
 	user_access_end();

arch/powerpc/kernel/signal_64.c

@@ -618,15 +618,12 @@ static long setup_trampoline(unsigned int syscall, unsigned int __user *tramp)
 	int i;
 	long err = 0;
 
-	/* bctrl # call the handler */
-	err |= __put_user(PPC_INST_BCTRL, &tramp[0]);
-	/* addi r1, r1, __SIGNAL_FRAMESIZE  # Pop the dummy stackframe */
-	err |= __put_user(PPC_INST_ADDI | __PPC_RT(R1) | __PPC_RA(R1) |
-			  (__SIGNAL_FRAMESIZE & 0xffff), &tramp[1]);
-	/* li r0, __NR_[rt_]sigreturn| */
-	err |= __put_user(PPC_INST_ADDI | (syscall & 0xffff), &tramp[2]);
-	/* sc */
-	err |= __put_user(PPC_INST_SC, &tramp[3]);
+	/* Call the handler and pop the dummy stackframe*/
+	err |= __put_user(PPC_RAW_BCTRL(), &tramp[0]);
+	err |= __put_user(PPC_RAW_ADDI(_R1, _R1, __SIGNAL_FRAMESIZE), &tramp[1]);
+
+	err |= __put_user(PPC_RAW_LI(_R0, syscall), &tramp[2]);
+	err |= __put_user(PPC_RAW_SC(), &tramp[3]);
 
 	/* Minimal traceback info */
 	for (i=TRAMP_TRACEBACK; i < TRAMP_SIZE ;i++)