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From: Anton Blanchard <anton@samba.org>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Subject: [PATCH 15/39] powerpc: Add little endian support to alignment handler
Date: Mon, 23 Sep 2013 12:04:49 +1000	[thread overview]
Message-ID: <1379901913-5945-16-git-send-email-anton@samba.org> (raw)
In-Reply-To: <1379901913-5945-1-git-send-email-anton@samba.org>

Handle most unaligned load and store faults in little
endian mode. Strings, multiples and VSX are not supported.

Signed-off-by: Anton Blanchard <anton@samba.org>
---
 arch/powerpc/kernel/align.c | 93 ++++++++++++++++++++++++++++++---------------
 1 file changed, 63 insertions(+), 30 deletions(-)

diff --git a/arch/powerpc/kernel/align.c b/arch/powerpc/kernel/align.c
index 3049bd0..cce82b1 100644
--- a/arch/powerpc/kernel/align.c
+++ b/arch/powerpc/kernel/align.c
@@ -262,6 +262,7 @@ static int emulate_dcbz(struct pt_regs *regs, unsigned char __user *addr)
 
 #define SWIZ_PTR(p)		((unsigned char __user *)((p) ^ swiz))
 
+#ifdef __BIG_ENDIAN__
 static int emulate_multiple(struct pt_regs *regs, unsigned char __user *addr,
 			    unsigned int reg, unsigned int nb,
 			    unsigned int flags, unsigned int instr,
@@ -390,6 +391,7 @@ static int emulate_fp_pair(unsigned char __user *addr, unsigned int reg,
 		return -EFAULT;
 	return 1;	/* exception handled and fixed up */
 }
+#endif
 
 #ifdef CONFIG_SPE
 
@@ -628,7 +630,7 @@ static int emulate_spe(struct pt_regs *regs, unsigned int reg,
 }
 #endif /* CONFIG_SPE */
 
-#ifdef CONFIG_VSX
+#if defined(CONFIG_VSX) && defined(__BIG_ENDIAN__)
 /*
  * Emulate VSX instructions...
  */
@@ -702,18 +704,28 @@ int fix_alignment(struct pt_regs *regs)
 	unsigned int dsisr;
 	unsigned char __user *addr;
 	unsigned long p, swiz;
-	int ret;
-	union {
+	int ret, i;
+	union data {
 		u64 ll;
 		double dd;
 		unsigned char v[8];
 		struct {
+#ifdef __LITTLE_ENDIAN__
+			int	 low32;
+			unsigned hi32;
+#else
 			unsigned hi32;
 			int	 low32;
+#endif
 		} x32;
 		struct {
+#ifdef __LITTLE_ENDIAN__
+			short	      low16;
+			unsigned char hi48[6];
+#else
 			unsigned char hi48[6];
 			short	      low16;
+#endif
 		} x16;
 	} data;
 
@@ -772,8 +784,9 @@ int fix_alignment(struct pt_regs *regs)
 
 	/* Byteswap little endian loads and stores */
 	swiz = 0;
-	if (regs->msr & MSR_LE) {
+	if ((regs->msr & MSR_LE) != (MSR_KERNEL & MSR_LE)) {
 		flags ^= SW;
+#ifdef __BIG_ENDIAN__
 		/*
 		 * So-called "PowerPC little endian" mode works by
 		 * swizzling addresses rather than by actually doing
@@ -786,11 +799,13 @@ int fix_alignment(struct pt_regs *regs)
 		 */
 		if (cpu_has_feature(CPU_FTR_PPC_LE))
 			swiz = 7;
+#endif
 	}
 
 	/* DAR has the operand effective address */
 	addr = (unsigned char __user *)regs->dar;
 
+#ifdef __BIG_ENDIAN__
 #ifdef CONFIG_VSX
 	if ((instruction & 0xfc00003e) == 0x7c000018) {
 		unsigned int elsize;
@@ -810,7 +825,7 @@ int fix_alignment(struct pt_regs *regs)
 			elsize = 8;
 
 		flags = 0;
-		if (regs->msr & MSR_LE)
+		if ((regs->msr & MSR_LE) != (MSR_KERNEL & MSR_LE))
 			flags |= SW;
 		if (instruction & 0x100)
 			flags |= ST;
@@ -825,6 +840,9 @@ int fix_alignment(struct pt_regs *regs)
 		return emulate_vsx(addr, reg, areg, regs, flags, nb, elsize);
 	}
 #endif
+#else
+	return -EFAULT;
+#endif
 	/* A size of 0 indicates an instruction we don't support, with
 	 * the exception of DCBZ which is handled as a special case here
 	 */
@@ -839,9 +857,13 @@ int fix_alignment(struct pt_regs *regs)
 	 * function
 	 */
 	if (flags & M) {
+#ifdef __BIG_ENDIAN__
 		PPC_WARN_ALIGNMENT(multiple, regs);
 		return emulate_multiple(regs, addr, reg, nb,
 					flags, instr, swiz);
+#else
+		return -EFAULT;
+#endif
 	}
 
 	/* Verify the address of the operand */
@@ -860,8 +882,12 @@ int fix_alignment(struct pt_regs *regs)
 
 	/* Special case for 16-byte FP loads and stores */
 	if (nb == 16) {
+#ifdef __BIG_ENDIAN__
 		PPC_WARN_ALIGNMENT(fp_pair, regs);
 		return emulate_fp_pair(addr, reg, flags);
+#else
+		return -EFAULT;
+#endif
 	}
 
 	PPC_WARN_ALIGNMENT(unaligned, regs);
@@ -870,24 +896,28 @@ int fix_alignment(struct pt_regs *regs)
 	 * get it from register values
 	 */
 	if (!(flags & ST)) {
-		data.ll = 0;
-		ret = 0;
-		p = (unsigned long) addr;
+		unsigned int start = 0;
+
 		switch (nb) {
-		case 8:
-			ret |= __get_user_inatomic(data.v[0], SWIZ_PTR(p++));
-			ret |= __get_user_inatomic(data.v[1], SWIZ_PTR(p++));
-			ret |= __get_user_inatomic(data.v[2], SWIZ_PTR(p++));
-			ret |= __get_user_inatomic(data.v[3], SWIZ_PTR(p++));
 		case 4:
-			ret |= __get_user_inatomic(data.v[4], SWIZ_PTR(p++));
-			ret |= __get_user_inatomic(data.v[5], SWIZ_PTR(p++));
+			start = offsetof(union data, x32.low32);
+			break;
 		case 2:
-			ret |= __get_user_inatomic(data.v[6], SWIZ_PTR(p++));
-			ret |= __get_user_inatomic(data.v[7], SWIZ_PTR(p++));
-			if (unlikely(ret))
-				return -EFAULT;
+			start = offsetof(union data, x16.low16);
+			break;
 		}
+
+		data.ll = 0;
+		ret = 0;
+		p = (unsigned long)addr;
+
+		for (i = 0; i < nb; i++)
+			ret |= __get_user_inatomic(data.v[start + i],
+						   SWIZ_PTR(p++));
+
+		if (unlikely(ret))
+			return -EFAULT;
+
 	} else if (flags & F) {
 		data.dd = current->thread.TS_FPR(reg);
 		if (flags & S) {
@@ -945,21 +975,24 @@ int fix_alignment(struct pt_regs *regs)
 
 	/* Store result to memory or update registers */
 	if (flags & ST) {
-		ret = 0;
-		p = (unsigned long) addr;
+		unsigned int start = 0;
+
 		switch (nb) {
-		case 8:
-			ret |= __put_user_inatomic(data.v[0], SWIZ_PTR(p++));
-			ret |= __put_user_inatomic(data.v[1], SWIZ_PTR(p++));
-			ret |= __put_user_inatomic(data.v[2], SWIZ_PTR(p++));
-			ret |= __put_user_inatomic(data.v[3], SWIZ_PTR(p++));
 		case 4:
-			ret |= __put_user_inatomic(data.v[4], SWIZ_PTR(p++));
-			ret |= __put_user_inatomic(data.v[5], SWIZ_PTR(p++));
+			start = offsetof(union data, x32.low32);
+			break;
 		case 2:
-			ret |= __put_user_inatomic(data.v[6], SWIZ_PTR(p++));
-			ret |= __put_user_inatomic(data.v[7], SWIZ_PTR(p++));
+			start = offsetof(union data, x16.low16);
+			break;
 		}
+
+		ret = 0;
+		p = (unsigned long)addr;
+
+		for (i = 0; i < nb; i++)
+			ret |= __put_user_inatomic(data.v[start + i],
+						   SWIZ_PTR(p++));
+
 		if (unlikely(ret))
 			return -EFAULT;
 	} else if (flags & F)
-- 
1.8.1.2

  parent reply	other threads:[~2013-09-23  2:04 UTC|newest]

Thread overview: 49+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-09-23  2:04 [PATCH 00/39] Second round of 64bit PowerPC little endian patches Anton Blanchard
2013-09-23  2:04 ` [PATCH 01/39] powerpc: Fix endian issues in VMX copy loops Anton Blanchard
2013-09-23  2:04 ` [PATCH 02/39] powerpc: Book 3S MMU little endian support Anton Blanchard
2013-09-23  2:04 ` [PATCH 03/39] powerpc: Fix offset of FPRs in VSX registers in little endian builds Anton Blanchard
2013-09-23  2:04 ` [PATCH 04/39] powerpc: PTRACE_PEEKUSR/PTRACE_POKEUSER of FPR " Anton Blanchard
2013-09-23  2:04 ` [PATCH 05/39] powerpc: Little endian builds double word swap VSX state during context save/restore Anton Blanchard
2013-09-23  2:04 ` [PATCH 06/39] powerpc: Support endian agnostic MMIO Anton Blanchard
2013-09-23  2:04 ` [PATCH 07/39] powerpc: Add little endian support for word-at-a-time functions Anton Blanchard
2013-09-23  2:04 ` [PATCH 08/39] powerpc: Set MSR_LE bit on little endian builds Anton Blanchard
2013-09-23  2:04 ` [PATCH 09/39] powerpc: Reset MSR_LE on signal entry Anton Blanchard
2013-09-23  2:04 ` [PATCH 10/39] powerpc: Include the appropriate endianness header Anton Blanchard
2013-09-23  2:04 ` [PATCH 11/39] powerpc: endian safe trampoline Anton Blanchard
2013-12-28  7:24   ` Olof Johansson
2013-12-28  7:58     ` Benjamin Herrenschmidt
2013-09-23  2:04 ` [PATCH 12/39] powerpc: Remove open coded byte swap macro in alignment handler Anton Blanchard
2013-09-23  2:04 ` [PATCH 13/39] powerpc: Remove hard coded FP offsets " Anton Blanchard
2013-09-23  2:04 ` [PATCH 14/39] powerpc: Alignment handler shouldn't access VSX registers with TS_FPR Anton Blanchard
2013-09-23  2:04 ` Anton Blanchard [this message]
2013-09-23  2:04 ` [PATCH 16/39] powerpc: Handle VSX alignment faults in little endian mode Anton Blanchard
2013-09-23  2:04 ` [PATCH 17/39] powerpc: Use generic checksum code in little endian Anton Blanchard
2013-09-23  2:04 ` [PATCH 18/39] powerpc: Use generic memcpy " Anton Blanchard
2013-09-23  2:04 ` [PATCH 19/39] powerpc: uname should return ppc64le/ppcle on little endian builds Anton Blanchard
2013-09-23  2:04 ` [PATCH 20/39] powerpc: Little endian fixes for platforms/powernv/opal.c Anton Blanchard
2013-09-23  2:04 ` [PATCH 21/39] powerpc: Little endian fix for arch/powerpc/platforms/powernv/pci.c Anton Blanchard
2013-09-23  2:04 ` [PATCH 22/39] powerpc: Little endian fix for arch/powerpc/platforms/powernv/pci-p5ioc2.c Anton Blanchard
2013-09-23  2:04 ` [PATCH 23/39] powerpc: Little endian sparse clean up for arch/powerpc/platforms/powernv/pci-ioda.c Anton Blanchard
2013-09-23  2:04 ` [PATCH 24/39] powerpc/powernv: Fix endian issues in OPAL RTC driver Anton Blanchard
2013-09-23  2:04 ` [PATCH 25/39] powerpc/powernv: Fix endian issues in OPAL ICS backend Anton Blanchard
2013-09-23  2:05 ` [PATCH 26/39] powerpc/powernv: Make OPAL NVRAM device tree accesses endian safe Anton Blanchard
2013-09-23  2:05 ` [PATCH 27/39] powerpc/powernv: Fix endian issues in powernv PCI code Anton Blanchard
2013-09-23  2:05 ` [PATCH 28/39] powerpc/powernv: Fix endian issues in OPAL console and udbg backend Anton Blanchard
2013-09-23  2:05 ` [PATCH 29/39] powerpc/powernv: Fix OPAL entry and exit in little endian mode Anton Blanchard
2013-09-23  2:05 ` [PATCH 30/39] powerpc/powernv: Don't register exception handlers " Anton Blanchard
2013-09-23  2:05 ` [PATCH 31/39] powerpc/powernv: More little endian issues in OPAL RTC driver Anton Blanchard
2013-09-23  2:05 ` [PATCH 32/39] powerpc/powernv: Fix some PCI sparse errors and one LE bug Anton Blanchard
2013-09-23  2:05 ` [PATCH 33/39] powerpc/hvsi: Fix endian issues in HVSI driver Anton Blanchard
2013-09-23  2:05 ` [PATCH 34/39] tty/hvc_opal: powerpc: Make OPAL HVC device tree accesses endian safe Anton Blanchard
2013-09-23  2:05 ` [PATCH 35/39] KVM: PPC: Disable KVM on little endian builds Anton Blanchard
2013-09-23  2:05 ` [PATCH 36/39] powerpc/kvm/book3s_hv: Add little endian guest support Anton Blanchard
2013-09-25 12:10   ` [PATCH] powerpc/kvmbook3s_hv: propagate H_SET_MODE to the host Laurent Dufour
2013-09-25 12:27     ` Greg Kurz
2013-09-25 22:31     ` Paul Mackerras
2013-09-27  8:14       ` Laurent Dufour
2013-09-27 13:59       ` [PATCH V2] powerpc/kvm/book3s_hv: propagate H_SET_MODE_RESOURCE_LE " Laurent Dufour
2013-09-27 14:45         ` Greg Kurz
2013-09-30 18:40   ` [PATCH 36/39] powerpc/kvm/book3s_hv: Add little endian guest support Alexander Graf
2013-09-23  2:05 ` [PATCH 37/39] powerpc: Add ability to build little endian kernels Anton Blanchard
2013-09-23  2:05 ` [PATCH 38/39] powerpc: Don't set HAVE_EFFICIENT_UNALIGNED_ACCESS on little endian builds Anton Blanchard
2013-09-23  2:05 ` [PATCH 39/39] powerpc: Work around little endian gcc bug Anton Blanchard

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