arm64/sysreg: Rename POE_RXW to POE_RWX

It is customary to list R, W, X permissions in that order. In fact
this is already the case for PIE constants (PIE_RWX). Rename POE_RXW
accordingly, as well as POE_XW (currently unused).

While at it also swap the W/X lines in
compute_s1_overlay_permissions() to follow the R, W, X order.

Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Link: https://lore.kernel.org/r/20250219164029.2309119-3-kevin.brodsky@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/include/asm/sysreg.h

@@ -1077,8 +1077,8 @@
 #define POE_RX		UL(0x3)
 #define POE_W		UL(0x4)
 #define POE_RW		UL(0x5)
-#define POE_XW		UL(0x6)
-#define POE_RXW		UL(0x7)
+#define POE_WX		UL(0x6)
+#define POE_RWX		UL(0x7)
 #define POE_MASK	UL(0xf)
 
 #define POR_ELx_BITS_PER_IDX		4
@@ -1087,7 +1087,7 @@
 #define POR_ELx_PERM_PREP(idx, perm)	(((perm) & POE_MASK) << POR_ELx_PERM_SHIFT(idx))
 
 /* Initial value for Permission Overlay Extension for EL0 */
-#define POR_EL0_INIT	POE_RXW
+#define POR_EL0_INIT	POE_RWX
 
 /*
  * Definitions for Guarded Control Stack

arch/arm64/kernel/signal.c

@@ -91,7 +91,7 @@ static void save_reset_user_access_state(struct user_access_state *ua_state)
 		u64 por_enable_all = 0;
 
 		for (int pkey = 0; pkey < arch_max_pkey(); pkey++)
-			por_enable_all |= POR_ELx_PERM_PREP(pkey, POE_RXW);
+			por_enable_all |= POR_ELx_PERM_PREP(pkey, POE_RWX);
 
 		ua_state->por_el0 = read_sysreg_s(SYS_POR_EL0);
 		write_sysreg_s(por_enable_all, SYS_POR_EL0);

arch/arm64/kvm/at.c

@@ -1090,22 +1090,22 @@ static void compute_s1_overlay_permissions(struct kvm_vcpu *vcpu,
 		break;
 	}
 
-	if (pov_perms & ~POE_RXW)
+	if (pov_perms & ~POE_RWX)
 		pov_perms = POE_NONE;
 
 	if (wi->poe && wr->pov) {
 		wr->pr &= pov_perms & POE_R;
-		wr->px &= pov_perms & POE_X;
 		wr->pw &= pov_perms & POE_W;
+		wr->px &= pov_perms & POE_X;
 	}
 
-	if (uov_perms & ~POE_RXW)
+	if (uov_perms & ~POE_RWX)
 		uov_perms = POE_NONE;
 
 	if (wi->e0poe && wr->uov) {
 		wr->ur &= uov_perms & POE_R;
-		wr->ux &= uov_perms & POE_X;
 		wr->uw &= uov_perms & POE_W;
+		wr->ux &= uov_perms & POE_X;
 	}
 }
 

arch/arm64/mm/mmu.c

@@ -1555,7 +1555,7 @@ void __cpu_replace_ttbr1(pgd_t *pgdp, bool cnp)
 #ifdef CONFIG_ARCH_HAS_PKEYS
 int arch_set_user_pkey_access(struct task_struct *tsk, int pkey, unsigned long init_val)
 {
-	u64 new_por = POE_RXW;
+	u64 new_por;
 	u64 old_por;
 
 	if (!system_supports_poe())
@@ -1570,7 +1570,7 @@ int arch_set_user_pkey_access(struct task_struct *tsk, int pkey, unsigned long i
 		return -EINVAL;
 
 	/* Set the bits we need in POR:  */
-	new_por = POE_RXW;
+	new_por = POE_RWX;
 	if (init_val & PKEY_DISABLE_WRITE)
 		new_por &= ~POE_W;
 	if (init_val & PKEY_DISABLE_ACCESS)