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-rw-r--r--arch/powerpc/kernel/align.c1042
1 files changed, 1042 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/align.c b/arch/powerpc/kernel/align.c
new file mode 100644
index 000000000..86150fbb4
--- /dev/null
+++ b/arch/powerpc/kernel/align.c
@@ -0,0 +1,1042 @@
+/* align.c - handle alignment exceptions for the Power PC.
+ *
+ * Copyright (c) 1996 Paul Mackerras <paulus@cs.anu.edu.au>
+ * Copyright (c) 1998-1999 TiVo, Inc.
+ * PowerPC 403GCX modifications.
+ * Copyright (c) 1999 Grant Erickson <grant@lcse.umn.edu>
+ * PowerPC 403GCX/405GP modifications.
+ * Copyright (c) 2001-2002 PPC64 team, IBM Corp
+ * 64-bit and Power4 support
+ * Copyright (c) 2005 Benjamin Herrenschmidt, IBM Corp
+ * <benh@kernel.crashing.org>
+ * Merge ppc32 and ppc64 implementations
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <asm/processor.h>
+#include <asm/uaccess.h>
+#include <asm/cache.h>
+#include <asm/cputable.h>
+#include <asm/emulated_ops.h>
+#include <asm/switch_to.h>
+#include <asm/disassemble.h>
+
+struct aligninfo {
+ unsigned char len;
+ unsigned char flags;
+};
+
+
+#define INVALID { 0, 0 }
+
+/* Bits in the flags field */
+#define LD 0 /* load */
+#define ST 1 /* store */
+#define SE 2 /* sign-extend value, or FP ld/st as word */
+#define F 4 /* to/from fp regs */
+#define U 8 /* update index register */
+#define M 0x10 /* multiple load/store */
+#define SW 0x20 /* byte swap */
+#define S 0x40 /* single-precision fp or... */
+#define SX 0x40 /* ... byte count in XER */
+#define HARD 0x80 /* string, stwcx. */
+#define E4 0x40 /* SPE endianness is word */
+#define E8 0x80 /* SPE endianness is double word */
+#define SPLT 0x80 /* VSX SPLAT load */
+
+/* DSISR bits reported for a DCBZ instruction: */
+#define DCBZ 0x5f /* 8xx/82xx dcbz faults when cache not enabled */
+
+/*
+ * The PowerPC stores certain bits of the instruction that caused the
+ * alignment exception in the DSISR register. This array maps those
+ * bits to information about the operand length and what the
+ * instruction would do.
+ */
+static struct aligninfo aligninfo[128] = {
+ { 4, LD }, /* 00 0 0000: lwz / lwarx */
+ INVALID, /* 00 0 0001 */
+ { 4, ST }, /* 00 0 0010: stw */
+ INVALID, /* 00 0 0011 */
+ { 2, LD }, /* 00 0 0100: lhz */
+ { 2, LD+SE }, /* 00 0 0101: lha */
+ { 2, ST }, /* 00 0 0110: sth */
+ { 4, LD+M }, /* 00 0 0111: lmw */
+ { 4, LD+F+S }, /* 00 0 1000: lfs */
+ { 8, LD+F }, /* 00 0 1001: lfd */
+ { 4, ST+F+S }, /* 00 0 1010: stfs */
+ { 8, ST+F }, /* 00 0 1011: stfd */
+ { 16, LD }, /* 00 0 1100: lq */
+ { 8, LD }, /* 00 0 1101: ld/ldu/lwa */
+ INVALID, /* 00 0 1110 */
+ { 8, ST }, /* 00 0 1111: std/stdu */
+ { 4, LD+U }, /* 00 1 0000: lwzu */
+ INVALID, /* 00 1 0001 */
+ { 4, ST+U }, /* 00 1 0010: stwu */
+ INVALID, /* 00 1 0011 */
+ { 2, LD+U }, /* 00 1 0100: lhzu */
+ { 2, LD+SE+U }, /* 00 1 0101: lhau */
+ { 2, ST+U }, /* 00 1 0110: sthu */
+ { 4, ST+M }, /* 00 1 0111: stmw */
+ { 4, LD+F+S+U }, /* 00 1 1000: lfsu */
+ { 8, LD+F+U }, /* 00 1 1001: lfdu */
+ { 4, ST+F+S+U }, /* 00 1 1010: stfsu */
+ { 8, ST+F+U }, /* 00 1 1011: stfdu */
+ { 16, LD+F }, /* 00 1 1100: lfdp */
+ INVALID, /* 00 1 1101 */
+ { 16, ST+F }, /* 00 1 1110: stfdp */
+ INVALID, /* 00 1 1111 */
+ { 8, LD }, /* 01 0 0000: ldx */
+ INVALID, /* 01 0 0001 */
+ { 8, ST }, /* 01 0 0010: stdx */
+ INVALID, /* 01 0 0011 */
+ INVALID, /* 01 0 0100 */
+ { 4, LD+SE }, /* 01 0 0101: lwax */
+ INVALID, /* 01 0 0110 */
+ INVALID, /* 01 0 0111 */
+ { 4, LD+M+HARD+SX }, /* 01 0 1000: lswx */
+ { 4, LD+M+HARD }, /* 01 0 1001: lswi */
+ { 4, ST+M+HARD+SX }, /* 01 0 1010: stswx */
+ { 4, ST+M+HARD }, /* 01 0 1011: stswi */
+ INVALID, /* 01 0 1100 */
+ { 8, LD+U }, /* 01 0 1101: ldu */
+ INVALID, /* 01 0 1110 */
+ { 8, ST+U }, /* 01 0 1111: stdu */
+ { 8, LD+U }, /* 01 1 0000: ldux */
+ INVALID, /* 01 1 0001 */
+ { 8, ST+U }, /* 01 1 0010: stdux */
+ INVALID, /* 01 1 0011 */
+ INVALID, /* 01 1 0100 */
+ { 4, LD+SE+U }, /* 01 1 0101: lwaux */
+ INVALID, /* 01 1 0110 */
+ INVALID, /* 01 1 0111 */
+ INVALID, /* 01 1 1000 */
+ INVALID, /* 01 1 1001 */
+ INVALID, /* 01 1 1010 */
+ INVALID, /* 01 1 1011 */
+ INVALID, /* 01 1 1100 */
+ INVALID, /* 01 1 1101 */
+ INVALID, /* 01 1 1110 */
+ INVALID, /* 01 1 1111 */
+ INVALID, /* 10 0 0000 */
+ INVALID, /* 10 0 0001 */
+ INVALID, /* 10 0 0010: stwcx. */
+ INVALID, /* 10 0 0011 */
+ INVALID, /* 10 0 0100 */
+ INVALID, /* 10 0 0101 */
+ INVALID, /* 10 0 0110 */
+ INVALID, /* 10 0 0111 */
+ { 4, LD+SW }, /* 10 0 1000: lwbrx */
+ INVALID, /* 10 0 1001 */
+ { 4, ST+SW }, /* 10 0 1010: stwbrx */
+ INVALID, /* 10 0 1011 */
+ { 2, LD+SW }, /* 10 0 1100: lhbrx */
+ { 4, LD+SE }, /* 10 0 1101 lwa */
+ { 2, ST+SW }, /* 10 0 1110: sthbrx */
+ { 16, ST }, /* 10 0 1111: stq */
+ INVALID, /* 10 1 0000 */
+ INVALID, /* 10 1 0001 */
+ INVALID, /* 10 1 0010 */
+ INVALID, /* 10 1 0011 */
+ INVALID, /* 10 1 0100 */
+ INVALID, /* 10 1 0101 */
+ INVALID, /* 10 1 0110 */
+ INVALID, /* 10 1 0111 */
+ INVALID, /* 10 1 1000 */
+ INVALID, /* 10 1 1001 */
+ INVALID, /* 10 1 1010 */
+ INVALID, /* 10 1 1011 */
+ INVALID, /* 10 1 1100 */
+ INVALID, /* 10 1 1101 */
+ INVALID, /* 10 1 1110 */
+ { 0, ST+HARD }, /* 10 1 1111: dcbz */
+ { 4, LD }, /* 11 0 0000: lwzx */
+ INVALID, /* 11 0 0001 */
+ { 4, ST }, /* 11 0 0010: stwx */
+ INVALID, /* 11 0 0011 */
+ { 2, LD }, /* 11 0 0100: lhzx */
+ { 2, LD+SE }, /* 11 0 0101: lhax */
+ { 2, ST }, /* 11 0 0110: sthx */
+ INVALID, /* 11 0 0111 */
+ { 4, LD+F+S }, /* 11 0 1000: lfsx */
+ { 8, LD+F }, /* 11 0 1001: lfdx */
+ { 4, ST+F+S }, /* 11 0 1010: stfsx */
+ { 8, ST+F }, /* 11 0 1011: stfdx */
+ { 16, LD+F }, /* 11 0 1100: lfdpx */
+ { 4, LD+F+SE }, /* 11 0 1101: lfiwax */
+ { 16, ST+F }, /* 11 0 1110: stfdpx */
+ { 4, ST+F }, /* 11 0 1111: stfiwx */
+ { 4, LD+U }, /* 11 1 0000: lwzux */
+ INVALID, /* 11 1 0001 */
+ { 4, ST+U }, /* 11 1 0010: stwux */
+ INVALID, /* 11 1 0011 */
+ { 2, LD+U }, /* 11 1 0100: lhzux */
+ { 2, LD+SE+U }, /* 11 1 0101: lhaux */
+ { 2, ST+U }, /* 11 1 0110: sthux */
+ INVALID, /* 11 1 0111 */
+ { 4, LD+F+S+U }, /* 11 1 1000: lfsux */
+ { 8, LD+F+U }, /* 11 1 1001: lfdux */
+ { 4, ST+F+S+U }, /* 11 1 1010: stfsux */
+ { 8, ST+F+U }, /* 11 1 1011: stfdux */
+ INVALID, /* 11 1 1100 */
+ { 4, LD+F }, /* 11 1 1101: lfiwzx */
+ INVALID, /* 11 1 1110 */
+ INVALID, /* 11 1 1111 */
+};
+
+/*
+ * The dcbz (data cache block zero) instruction
+ * gives an alignment fault if used on non-cacheable
+ * memory. We handle the fault mainly for the
+ * case when we are running with the cache disabled
+ * for debugging.
+ */
+static int emulate_dcbz(struct pt_regs *regs, unsigned char __user *addr)
+{
+ long __user *p;
+ int i, size;
+
+#ifdef __powerpc64__
+ size = ppc64_caches.dline_size;
+#else
+ size = L1_CACHE_BYTES;
+#endif
+ p = (long __user *) (regs->dar & -size);
+ if (user_mode(regs) && !access_ok(VERIFY_WRITE, p, size))
+ return -EFAULT;
+ for (i = 0; i < size / sizeof(long); ++i)
+ if (__put_user_inatomic(0, p+i))
+ return -EFAULT;
+ return 1;
+}
+
+/*
+ * Emulate load & store multiple instructions
+ * On 64-bit machines, these instructions only affect/use the
+ * bottom 4 bytes of each register, and the loads clear the
+ * top 4 bytes of the affected register.
+ */
+#ifdef __BIG_ENDIAN__
+#ifdef CONFIG_PPC64
+#define REG_BYTE(rp, i) *((u8 *)((rp) + ((i) >> 2)) + ((i) & 3) + 4)
+#else
+#define REG_BYTE(rp, i) *((u8 *)(rp) + (i))
+#endif
+#endif
+
+#ifdef __LITTLE_ENDIAN__
+#define REG_BYTE(rp, i) (*(((u8 *)((rp) + ((i)>>2)) + ((i)&3))))
+#endif
+
+#define SWIZ_PTR(p) ((unsigned char __user *)((p) ^ swiz))
+
+static int emulate_multiple(struct pt_regs *regs, unsigned char __user *addr,
+ unsigned int reg, unsigned int nb,
+ unsigned int flags, unsigned int instr,
+ unsigned long swiz)
+{
+ unsigned long *rptr;
+ unsigned int nb0, i, bswiz;
+ unsigned long p;
+
+ /*
+ * We do not try to emulate 8 bytes multiple as they aren't really
+ * available in our operating environments and we don't try to
+ * emulate multiples operations in kernel land as they should never
+ * be used/generated there at least not on unaligned boundaries
+ */
+ if (unlikely((nb > 4) || !user_mode(regs)))
+ return 0;
+
+ /* lmw, stmw, lswi/x, stswi/x */
+ nb0 = 0;
+ if (flags & HARD) {
+ if (flags & SX) {
+ nb = regs->xer & 127;
+ if (nb == 0)
+ return 1;
+ } else {
+ unsigned long pc = regs->nip ^ (swiz & 4);
+
+ if (__get_user_inatomic(instr,
+ (unsigned int __user *)pc))
+ return -EFAULT;
+ if (swiz == 0 && (flags & SW))
+ instr = cpu_to_le32(instr);
+ nb = (instr >> 11) & 0x1f;
+ if (nb == 0)
+ nb = 32;
+ }
+ if (nb + reg * 4 > 128) {
+ nb0 = nb + reg * 4 - 128;
+ nb = 128 - reg * 4;
+ }
+#ifdef __LITTLE_ENDIAN__
+ /*
+ * String instructions are endian neutral but the code
+ * below is not. Force byte swapping on so that the
+ * effects of swizzling are undone in the load/store
+ * loops below.
+ */
+ flags ^= SW;
+#endif
+ } else {
+ /* lwm, stmw */
+ nb = (32 - reg) * 4;
+ }
+
+ if (!access_ok((flags & ST ? VERIFY_WRITE: VERIFY_READ), addr, nb+nb0))
+ return -EFAULT; /* bad address */
+
+ rptr = &regs->gpr[reg];
+ p = (unsigned long) addr;
+ bswiz = (flags & SW)? 3: 0;
+
+ if (!(flags & ST)) {
+ /*
+ * This zeroes the top 4 bytes of the affected registers
+ * in 64-bit mode, and also zeroes out any remaining
+ * bytes of the last register for lsw*.
+ */
+ memset(rptr, 0, ((nb + 3) / 4) * sizeof(unsigned long));
+ if (nb0 > 0)
+ memset(&regs->gpr[0], 0,
+ ((nb0 + 3) / 4) * sizeof(unsigned long));
+
+ for (i = 0; i < nb; ++i, ++p)
+ if (__get_user_inatomic(REG_BYTE(rptr, i ^ bswiz),
+ SWIZ_PTR(p)))
+ return -EFAULT;
+ if (nb0 > 0) {
+ rptr = &regs->gpr[0];
+ addr += nb;
+ for (i = 0; i < nb0; ++i, ++p)
+ if (__get_user_inatomic(REG_BYTE(rptr,
+ i ^ bswiz),
+ SWIZ_PTR(p)))
+ return -EFAULT;
+ }
+
+ } else {
+ for (i = 0; i < nb; ++i, ++p)
+ if (__put_user_inatomic(REG_BYTE(rptr, i ^ bswiz),
+ SWIZ_PTR(p)))
+ return -EFAULT;
+ if (nb0 > 0) {
+ rptr = &regs->gpr[0];
+ addr += nb;
+ for (i = 0; i < nb0; ++i, ++p)
+ if (__put_user_inatomic(REG_BYTE(rptr,
+ i ^ bswiz),
+ SWIZ_PTR(p)))
+ return -EFAULT;
+ }
+ }
+ return 1;
+}
+
+/*
+ * Emulate floating-point pair loads and stores.
+ * Only POWER6 has these instructions, and it does true little-endian,
+ * so we don't need the address swizzling.
+ */
+static int emulate_fp_pair(unsigned char __user *addr, unsigned int reg,
+ unsigned int flags)
+{
+ char *ptr0 = (char *) &current->thread.TS_FPR(reg);
+ char *ptr1 = (char *) &current->thread.TS_FPR(reg+1);
+ int i, ret, sw = 0;
+
+ if (reg & 1)
+ return 0; /* invalid form: FRS/FRT must be even */
+ if (flags & SW)
+ sw = 7;
+ ret = 0;
+ for (i = 0; i < 8; ++i) {
+ if (!(flags & ST)) {
+ ret |= __get_user(ptr0[i^sw], addr + i);
+ ret |= __get_user(ptr1[i^sw], addr + i + 8);
+ } else {
+ ret |= __put_user(ptr0[i^sw], addr + i);
+ ret |= __put_user(ptr1[i^sw], addr + i + 8);
+ }
+ }
+ if (ret)
+ return -EFAULT;
+ return 1; /* exception handled and fixed up */
+}
+
+#ifdef CONFIG_PPC64
+static int emulate_lq_stq(struct pt_regs *regs, unsigned char __user *addr,
+ unsigned int reg, unsigned int flags)
+{
+ char *ptr0 = (char *)&regs->gpr[reg];
+ char *ptr1 = (char *)&regs->gpr[reg+1];
+ int i, ret, sw = 0;
+
+ if (reg & 1)
+ return 0; /* invalid form: GPR must be even */
+ if (flags & SW)
+ sw = 7;
+ ret = 0;
+ for (i = 0; i < 8; ++i) {
+ if (!(flags & ST)) {
+ ret |= __get_user(ptr0[i^sw], addr + i);
+ ret |= __get_user(ptr1[i^sw], addr + i + 8);
+ } else {
+ ret |= __put_user(ptr0[i^sw], addr + i);
+ ret |= __put_user(ptr1[i^sw], addr + i + 8);
+ }
+ }
+ if (ret)
+ return -EFAULT;
+ return 1; /* exception handled and fixed up */
+}
+#endif /* CONFIG_PPC64 */
+
+#ifdef CONFIG_SPE
+
+static struct aligninfo spe_aligninfo[32] = {
+ { 8, LD+E8 }, /* 0 00 00: evldd[x] */
+ { 8, LD+E4 }, /* 0 00 01: evldw[x] */
+ { 8, LD }, /* 0 00 10: evldh[x] */
+ INVALID, /* 0 00 11 */
+ { 2, LD }, /* 0 01 00: evlhhesplat[x] */
+ INVALID, /* 0 01 01 */
+ { 2, LD }, /* 0 01 10: evlhhousplat[x] */
+ { 2, LD+SE }, /* 0 01 11: evlhhossplat[x] */
+ { 4, LD }, /* 0 10 00: evlwhe[x] */
+ INVALID, /* 0 10 01 */
+ { 4, LD }, /* 0 10 10: evlwhou[x] */
+ { 4, LD+SE }, /* 0 10 11: evlwhos[x] */
+ { 4, LD+E4 }, /* 0 11 00: evlwwsplat[x] */
+ INVALID, /* 0 11 01 */
+ { 4, LD }, /* 0 11 10: evlwhsplat[x] */
+ INVALID, /* 0 11 11 */
+
+ { 8, ST+E8 }, /* 1 00 00: evstdd[x] */
+ { 8, ST+E4 }, /* 1 00 01: evstdw[x] */
+ { 8, ST }, /* 1 00 10: evstdh[x] */
+ INVALID, /* 1 00 11 */
+ INVALID, /* 1 01 00 */
+ INVALID, /* 1 01 01 */
+ INVALID, /* 1 01 10 */
+ INVALID, /* 1 01 11 */
+ { 4, ST }, /* 1 10 00: evstwhe[x] */
+ INVALID, /* 1 10 01 */
+ { 4, ST }, /* 1 10 10: evstwho[x] */
+ INVALID, /* 1 10 11 */
+ { 4, ST+E4 }, /* 1 11 00: evstwwe[x] */
+ INVALID, /* 1 11 01 */
+ { 4, ST+E4 }, /* 1 11 10: evstwwo[x] */
+ INVALID, /* 1 11 11 */
+};
+
+#define EVLDD 0x00
+#define EVLDW 0x01
+#define EVLDH 0x02
+#define EVLHHESPLAT 0x04
+#define EVLHHOUSPLAT 0x06
+#define EVLHHOSSPLAT 0x07
+#define EVLWHE 0x08
+#define EVLWHOU 0x0A
+#define EVLWHOS 0x0B
+#define EVLWWSPLAT 0x0C
+#define EVLWHSPLAT 0x0E
+#define EVSTDD 0x10
+#define EVSTDW 0x11
+#define EVSTDH 0x12
+#define EVSTWHE 0x18
+#define EVSTWHO 0x1A
+#define EVSTWWE 0x1C
+#define EVSTWWO 0x1E
+
+/*
+ * Emulate SPE loads and stores.
+ * Only Book-E has these instructions, and it does true little-endian,
+ * so we don't need the address swizzling.
+ */
+static int emulate_spe(struct pt_regs *regs, unsigned int reg,
+ unsigned int instr)
+{
+ int ret;
+ union {
+ u64 ll;
+ u32 w[2];
+ u16 h[4];
+ u8 v[8];
+ } data, temp;
+ unsigned char __user *p, *addr;
+ unsigned long *evr = &current->thread.evr[reg];
+ unsigned int nb, flags;
+
+ instr = (instr >> 1) & 0x1f;
+
+ /* DAR has the operand effective address */
+ addr = (unsigned char __user *)regs->dar;
+
+ nb = spe_aligninfo[instr].len;
+ flags = spe_aligninfo[instr].flags;
+
+ /* Verify the address of the operand */
+ if (unlikely(user_mode(regs) &&
+ !access_ok((flags & ST ? VERIFY_WRITE : VERIFY_READ),
+ addr, nb)))
+ return -EFAULT;
+
+ /* userland only */
+ if (unlikely(!user_mode(regs)))
+ return 0;
+
+ flush_spe_to_thread(current);
+
+ /* If we are loading, get the data from user space, else
+ * get it from register values
+ */
+ if (flags & ST) {
+ data.ll = 0;
+ switch (instr) {
+ case EVSTDD:
+ case EVSTDW:
+ case EVSTDH:
+ data.w[0] = *evr;
+ data.w[1] = regs->gpr[reg];
+ break;
+ case EVSTWHE:
+ data.h[2] = *evr >> 16;
+ data.h[3] = regs->gpr[reg] >> 16;
+ break;
+ case EVSTWHO:
+ data.h[2] = *evr & 0xffff;
+ data.h[3] = regs->gpr[reg] & 0xffff;
+ break;
+ case EVSTWWE:
+ data.w[1] = *evr;
+ break;
+ case EVSTWWO:
+ data.w[1] = regs->gpr[reg];
+ break;
+ default:
+ return -EINVAL;
+ }
+ } else {
+ temp.ll = data.ll = 0;
+ ret = 0;
+ p = addr;
+
+ switch (nb) {
+ case 8:
+ ret |= __get_user_inatomic(temp.v[0], p++);
+ ret |= __get_user_inatomic(temp.v[1], p++);
+ ret |= __get_user_inatomic(temp.v[2], p++);
+ ret |= __get_user_inatomic(temp.v[3], p++);
+ case 4:
+ ret |= __get_user_inatomic(temp.v[4], p++);
+ ret |= __get_user_inatomic(temp.v[5], p++);
+ case 2:
+ ret |= __get_user_inatomic(temp.v[6], p++);
+ ret |= __get_user_inatomic(temp.v[7], p++);
+ if (unlikely(ret))
+ return -EFAULT;
+ }
+
+ switch (instr) {
+ case EVLDD:
+ case EVLDW:
+ case EVLDH:
+ data.ll = temp.ll;
+ break;
+ case EVLHHESPLAT:
+ data.h[0] = temp.h[3];
+ data.h[2] = temp.h[3];
+ break;
+ case EVLHHOUSPLAT:
+ case EVLHHOSSPLAT:
+ data.h[1] = temp.h[3];
+ data.h[3] = temp.h[3];
+ break;
+ case EVLWHE:
+ data.h[0] = temp.h[2];
+ data.h[2] = temp.h[3];
+ break;
+ case EVLWHOU:
+ case EVLWHOS:
+ data.h[1] = temp.h[2];
+ data.h[3] = temp.h[3];
+ break;
+ case EVLWWSPLAT:
+ data.w[0] = temp.w[1];
+ data.w[1] = temp.w[1];
+ break;
+ case EVLWHSPLAT:
+ data.h[0] = temp.h[2];
+ data.h[1] = temp.h[2];
+ data.h[2] = temp.h[3];
+ data.h[3] = temp.h[3];
+ break;
+ default:
+ return -EINVAL;
+ }
+ }
+
+ if (flags & SW) {
+ switch (flags & 0xf0) {
+ case E8:
+ data.ll = swab64(data.ll);
+ break;
+ case E4:
+ data.w[0] = swab32(data.w[0]);
+ data.w[1] = swab32(data.w[1]);
+ break;
+ /* Its half word endian */
+ default:
+ data.h[0] = swab16(data.h[0]);
+ data.h[1] = swab16(data.h[1]);
+ data.h[2] = swab16(data.h[2]);
+ data.h[3] = swab16(data.h[3]);
+ break;
+ }
+ }
+
+ if (flags & SE) {
+ data.w[0] = (s16)data.h[1];
+ data.w[1] = (s16)data.h[3];
+ }
+
+ /* Store result to memory or update registers */
+ if (flags & ST) {
+ ret = 0;
+ p = addr;
+ switch (nb) {
+ case 8:
+ ret |= __put_user_inatomic(data.v[0], p++);
+ ret |= __put_user_inatomic(data.v[1], p++);
+ ret |= __put_user_inatomic(data.v[2], p++);
+ ret |= __put_user_inatomic(data.v[3], p++);
+ case 4:
+ ret |= __put_user_inatomic(data.v[4], p++);
+ ret |= __put_user_inatomic(data.v[5], p++);
+ case 2:
+ ret |= __put_user_inatomic(data.v[6], p++);
+ ret |= __put_user_inatomic(data.v[7], p++);
+ }
+ if (unlikely(ret))
+ return -EFAULT;
+ } else {
+ *evr = data.w[0];
+ regs->gpr[reg] = data.w[1];
+ }
+
+ return 1;
+}
+#endif /* CONFIG_SPE */
+
+#ifdef CONFIG_VSX
+/*
+ * Emulate VSX instructions...
+ */
+static int emulate_vsx(unsigned char __user *addr, unsigned int reg,
+ unsigned int areg, struct pt_regs *regs,
+ unsigned int flags, unsigned int length,
+ unsigned int elsize)
+{
+ char *ptr;
+ unsigned long *lptr;
+ int ret = 0;
+ int sw = 0;
+ int i, j;
+
+ /* userland only */
+ if (unlikely(!user_mode(regs)))
+ return 0;
+
+ flush_vsx_to_thread(current);
+
+ if (reg < 32)
+ ptr = (char *) &current->thread.fp_state.fpr[reg][0];
+ else
+ ptr = (char *) &current->thread.vr_state.vr[reg - 32];
+
+ lptr = (unsigned long *) ptr;
+
+#ifdef __LITTLE_ENDIAN__
+ if (flags & SW) {
+ elsize = length;
+ sw = length-1;
+ } else {
+ /*
+ * The elements are BE ordered, even in LE mode, so process
+ * them in reverse order.
+ */
+ addr += length - elsize;
+
+ /* 8 byte memory accesses go in the top 8 bytes of the VR */
+ if (length == 8)
+ ptr += 8;
+ }
+#else
+ if (flags & SW)
+ sw = elsize-1;
+#endif
+
+ for (j = 0; j < length; j += elsize) {
+ for (i = 0; i < elsize; ++i) {
+ if (flags & ST)
+ ret |= __put_user(ptr[i^sw], addr + i);
+ else
+ ret |= __get_user(ptr[i^sw], addr + i);
+ }
+ ptr += elsize;
+#ifdef __LITTLE_ENDIAN__
+ addr -= elsize;
+#else
+ addr += elsize;
+#endif
+ }
+
+#ifdef __BIG_ENDIAN__
+#define VSX_HI 0
+#define VSX_LO 1
+#else
+#define VSX_HI 1
+#define VSX_LO 0
+#endif
+
+ if (!ret) {
+ if (flags & U)
+ regs->gpr[areg] = regs->dar;
+
+ /* Splat load copies the same data to top and bottom 8 bytes */
+ if (flags & SPLT)
+ lptr[VSX_LO] = lptr[VSX_HI];
+ /* For 8 byte loads, zero the low 8 bytes */
+ else if (!(flags & ST) && (8 == length))
+ lptr[VSX_LO] = 0;
+ } else
+ return -EFAULT;
+
+ return 1;
+}
+#endif
+
+/*
+ * Called on alignment exception. Attempts to fixup
+ *
+ * Return 1 on success
+ * Return 0 if unable to handle the interrupt
+ * Return -EFAULT if data address is bad
+ */
+
+int fix_alignment(struct pt_regs *regs)
+{
+ unsigned int instr, nb, flags, instruction = 0;
+ unsigned int reg, areg;
+ unsigned int dsisr;
+ unsigned char __user *addr;
+ unsigned long p, swiz;
+ 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;
+
+ /*
+ * We require a complete register set, if not, then our assembly
+ * is broken
+ */
+ CHECK_FULL_REGS(regs);
+
+ dsisr = regs->dsisr;
+
+ /* Some processors don't provide us with a DSISR we can use here,
+ * let's make one up from the instruction
+ */
+ if (cpu_has_feature(CPU_FTR_NODSISRALIGN)) {
+ unsigned long pc = regs->nip;
+
+ if (cpu_has_feature(CPU_FTR_PPC_LE) && (regs->msr & MSR_LE))
+ pc ^= 4;
+ if (unlikely(__get_user_inatomic(instr,
+ (unsigned int __user *)pc)))
+ return -EFAULT;
+ if (cpu_has_feature(CPU_FTR_REAL_LE) && (regs->msr & MSR_LE))
+ instr = cpu_to_le32(instr);
+ dsisr = make_dsisr(instr);
+ instruction = instr;
+ }
+
+ /* extract the operation and registers from the dsisr */
+ reg = (dsisr >> 5) & 0x1f; /* source/dest register */
+ areg = dsisr & 0x1f; /* register to update */
+
+#ifdef CONFIG_SPE
+ if ((instr >> 26) == 0x4) {
+ PPC_WARN_ALIGNMENT(spe, regs);
+ return emulate_spe(regs, reg, instr);
+ }
+#endif
+
+ instr = (dsisr >> 10) & 0x7f;
+ instr |= (dsisr >> 13) & 0x60;
+
+ /* Lookup the operation in our table */
+ nb = aligninfo[instr].len;
+ flags = aligninfo[instr].flags;
+
+ /* ldbrx/stdbrx overlap lfs/stfs in the DSISR unfortunately */
+ if (IS_XFORM(instruction) && ((instruction >> 1) & 0x3ff) == 532) {
+ nb = 8;
+ flags = LD+SW;
+ } else if (IS_XFORM(instruction) &&
+ ((instruction >> 1) & 0x3ff) == 660) {
+ nb = 8;
+ flags = ST+SW;
+ }
+
+ /* Byteswap little endian loads and stores */
+ swiz = 0;
+ 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
+ * any byte-swapping. To emulate this, we XOR each
+ * byte address with 7. We also byte-swap, because
+ * the processor's address swizzling depends on the
+ * operand size (it xors the address with 7 for bytes,
+ * 6 for halfwords, 4 for words, 0 for doublewords) but
+ * we will xor with 7 and load/store each byte separately.
+ */
+ if (cpu_has_feature(CPU_FTR_PPC_LE))
+ swiz = 7;
+#endif
+ }
+
+ /* DAR has the operand effective address */
+ addr = (unsigned char __user *)regs->dar;
+
+#ifdef CONFIG_VSX
+ if ((instruction & 0xfc00003e) == 0x7c000018) {
+ unsigned int elsize;
+
+ /* Additional register addressing bit (64 VSX vs 32 FPR/GPR) */
+ reg |= (instruction & 0x1) << 5;
+ /* Simple inline decoder instead of a table */
+ /* VSX has only 8 and 16 byte memory accesses */
+ nb = 8;
+ if (instruction & 0x200)
+ nb = 16;
+
+ /* Vector stores in little-endian mode swap individual
+ elements, so process them separately */
+ elsize = 4;
+ if (instruction & 0x80)
+ elsize = 8;
+
+ flags = 0;
+ if ((regs->msr & MSR_LE) != (MSR_KERNEL & MSR_LE))
+ flags |= SW;
+ if (instruction & 0x100)
+ flags |= ST;
+ if (instruction & 0x040)
+ flags |= U;
+ /* splat load needs a special decoder */
+ if ((instruction & 0x400) == 0){
+ flags |= SPLT;
+ nb = 8;
+ }
+ PPC_WARN_ALIGNMENT(vsx, regs);
+ return emulate_vsx(addr, reg, areg, regs, flags, nb, elsize);
+ }
+#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
+ */
+ if (instr == DCBZ) {
+ PPC_WARN_ALIGNMENT(dcbz, regs);
+ return emulate_dcbz(regs, addr);
+ }
+ if (unlikely(nb == 0))
+ return 0;
+
+ /* Load/Store Multiple instructions are handled in their own
+ * function
+ */
+ if (flags & M) {
+ PPC_WARN_ALIGNMENT(multiple, regs);
+ return emulate_multiple(regs, addr, reg, nb,
+ flags, instr, swiz);
+ }
+
+ /* Verify the address of the operand */
+ if (unlikely(user_mode(regs) &&
+ !access_ok((flags & ST ? VERIFY_WRITE : VERIFY_READ),
+ addr, nb)))
+ return -EFAULT;
+
+ /* Force the fprs into the save area so we can reference them */
+ if (flags & F) {
+ /* userland only */
+ if (unlikely(!user_mode(regs)))
+ return 0;
+ flush_fp_to_thread(current);
+ }
+
+ if (nb == 16) {
+ if (flags & F) {
+ /* Special case for 16-byte FP loads and stores */
+ PPC_WARN_ALIGNMENT(fp_pair, regs);
+ return emulate_fp_pair(addr, reg, flags);
+ } else {
+#ifdef CONFIG_PPC64
+ /* Special case for 16-byte loads and stores */
+ PPC_WARN_ALIGNMENT(lq_stq, regs);
+ return emulate_lq_stq(regs, addr, reg, flags);
+#else
+ return 0;
+#endif
+ }
+ }
+
+ PPC_WARN_ALIGNMENT(unaligned, regs);
+
+ /* If we are loading, get the data from user space, else
+ * get it from register values
+ */
+ if (!(flags & ST)) {
+ unsigned int start = 0;
+
+ switch (nb) {
+ case 4:
+ start = offsetof(union data, x32.low32);
+ break;
+ case 2:
+ 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.ll = current->thread.TS_FPR(reg);
+ if (flags & S) {
+ /* Single-precision FP store requires conversion... */
+#ifdef CONFIG_PPC_FPU
+ preempt_disable();
+ enable_kernel_fp();
+ cvt_df(&data.dd, (float *)&data.x32.low32);
+ preempt_enable();
+#else
+ return 0;
+#endif
+ }
+ } else
+ data.ll = regs->gpr[reg];
+
+ if (flags & SW) {
+ switch (nb) {
+ case 8:
+ data.ll = swab64(data.ll);
+ break;
+ case 4:
+ data.x32.low32 = swab32(data.x32.low32);
+ break;
+ case 2:
+ data.x16.low16 = swab16(data.x16.low16);
+ break;
+ }
+ }
+
+ /* Perform other misc operations like sign extension
+ * or floating point single precision conversion
+ */
+ switch (flags & ~(U|SW)) {
+ case LD+SE: /* sign extending integer loads */
+ case LD+F+SE: /* sign extend for lfiwax */
+ if ( nb == 2 )
+ data.ll = data.x16.low16;
+ else /* nb must be 4 */
+ data.ll = data.x32.low32;
+ break;
+
+ /* Single-precision FP load requires conversion... */
+ case LD+F+S:
+#ifdef CONFIG_PPC_FPU
+ preempt_disable();
+ enable_kernel_fp();
+ cvt_fd((float *)&data.x32.low32, &data.dd);
+ preempt_enable();
+#else
+ return 0;
+#endif
+ break;
+ }
+
+ /* Store result to memory or update registers */
+ if (flags & ST) {
+ unsigned int start = 0;
+
+ switch (nb) {
+ case 4:
+ start = offsetof(union data, x32.low32);
+ break;
+ case 2:
+ 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)
+ current->thread.TS_FPR(reg) = data.ll;
+ else
+ regs->gpr[reg] = data.ll;
+
+ /* Update RA as needed */
+ if (flags & U)
+ regs->gpr[areg] = regs->dar;
+
+ return 1;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-27 23:46:18 +0000