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Diffstat (limited to 'arch/sparc/kernel/unaligned_64.c')
-rw-r--r--arch/sparc/kernel/unaligned_64.c694
1 files changed, 694 insertions, 0 deletions
diff --git a/arch/sparc/kernel/unaligned_64.c b/arch/sparc/kernel/unaligned_64.c
new file mode 100644
index 00000000000..379209982a0
--- /dev/null
+++ b/arch/sparc/kernel/unaligned_64.c
@@ -0,0 +1,694 @@
+/*
+ * unaligned.c: Unaligned load/store trap handling with special
+ * cases for the kernel to do them more quickly.
+ *
+ * Copyright (C) 1996,2008 David S. Miller (davem@davemloft.net)
+ * Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ */
+
+
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <asm/asi.h>
+#include <asm/ptrace.h>
+#include <asm/pstate.h>
+#include <asm/processor.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <linux/smp.h>
+#include <linux/bitops.h>
+#include <asm/fpumacro.h>
+
+/* #define DEBUG_MNA */
+
+enum direction {
+ load, /* ld, ldd, ldh, ldsh */
+ store, /* st, std, sth, stsh */
+ both, /* Swap, ldstub, cas, ... */
+ fpld,
+ fpst,
+ invalid,
+};
+
+#ifdef DEBUG_MNA
+static char *dirstrings[] = {
+ "load", "store", "both", "fpload", "fpstore", "invalid"
+};
+#endif
+
+static inline enum direction decode_direction(unsigned int insn)
+{
+ unsigned long tmp = (insn >> 21) & 1;
+
+ if (!tmp)
+ return load;
+ else {
+ switch ((insn>>19)&0xf) {
+ case 15: /* swap* */
+ return both;
+ default:
+ return store;
+ }
+ }
+}
+
+/* 16 = double-word, 8 = extra-word, 4 = word, 2 = half-word */
+static inline int decode_access_size(unsigned int insn)
+{
+ unsigned int tmp;
+
+ tmp = ((insn >> 19) & 0xf);
+ if (tmp == 11 || tmp == 14) /* ldx/stx */
+ return 8;
+ tmp &= 3;
+ if (!tmp)
+ return 4;
+ else if (tmp == 3)
+ return 16; /* ldd/std - Although it is actually 8 */
+ else if (tmp == 2)
+ return 2;
+ else {
+ printk("Impossible unaligned trap. insn=%08x\n", insn);
+ die_if_kernel("Byte sized unaligned access?!?!", current_thread_info()->kregs);
+
+ /* GCC should never warn that control reaches the end
+ * of this function without returning a value because
+ * die_if_kernel() is marked with attribute 'noreturn'.
+ * Alas, some versions do...
+ */
+
+ return 0;
+ }
+}
+
+static inline int decode_asi(unsigned int insn, struct pt_regs *regs)
+{
+ if (insn & 0x800000) {
+ if (insn & 0x2000)
+ return (unsigned char)(regs->tstate >> 24); /* %asi */
+ else
+ return (unsigned char)(insn >> 5); /* imm_asi */
+ } else
+ return ASI_P;
+}
+
+/* 0x400000 = signed, 0 = unsigned */
+static inline int decode_signedness(unsigned int insn)
+{
+ return (insn & 0x400000);
+}
+
+static inline void maybe_flush_windows(unsigned int rs1, unsigned int rs2,
+ unsigned int rd, int from_kernel)
+{
+ if (rs2 >= 16 || rs1 >= 16 || rd >= 16) {
+ if (from_kernel != 0)
+ __asm__ __volatile__("flushw");
+ else
+ flushw_user();
+ }
+}
+
+static inline long sign_extend_imm13(long imm)
+{
+ return imm << 51 >> 51;
+}
+
+static unsigned long fetch_reg(unsigned int reg, struct pt_regs *regs)
+{
+ unsigned long value;
+
+ if (reg < 16)
+ return (!reg ? 0 : regs->u_regs[reg]);
+ if (regs->tstate & TSTATE_PRIV) {
+ struct reg_window *win;
+ win = (struct reg_window *)(regs->u_regs[UREG_FP] + STACK_BIAS);
+ value = win->locals[reg - 16];
+ } else if (test_thread_flag(TIF_32BIT)) {
+ struct reg_window32 __user *win32;
+ win32 = (struct reg_window32 __user *)((unsigned long)((u32)regs->u_regs[UREG_FP]));
+ get_user(value, &win32->locals[reg - 16]);
+ } else {
+ struct reg_window __user *win;
+ win = (struct reg_window __user *)(regs->u_regs[UREG_FP] + STACK_BIAS);
+ get_user(value, &win->locals[reg - 16]);
+ }
+ return value;
+}
+
+static unsigned long *fetch_reg_addr(unsigned int reg, struct pt_regs *regs)
+{
+ if (reg < 16)
+ return &regs->u_regs[reg];
+ if (regs->tstate & TSTATE_PRIV) {
+ struct reg_window *win;
+ win = (struct reg_window *)(regs->u_regs[UREG_FP] + STACK_BIAS);
+ return &win->locals[reg - 16];
+ } else if (test_thread_flag(TIF_32BIT)) {
+ struct reg_window32 *win32;
+ win32 = (struct reg_window32 *)((unsigned long)((u32)regs->u_regs[UREG_FP]));
+ return (unsigned long *)&win32->locals[reg - 16];
+ } else {
+ struct reg_window *win;
+ win = (struct reg_window *)(regs->u_regs[UREG_FP] + STACK_BIAS);
+ return &win->locals[reg - 16];
+ }
+}
+
+unsigned long compute_effective_address(struct pt_regs *regs,
+ unsigned int insn, unsigned int rd)
+{
+ unsigned int rs1 = (insn >> 14) & 0x1f;
+ unsigned int rs2 = insn & 0x1f;
+ int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
+
+ if (insn & 0x2000) {
+ maybe_flush_windows(rs1, 0, rd, from_kernel);
+ return (fetch_reg(rs1, regs) + sign_extend_imm13(insn));
+ } else {
+ maybe_flush_windows(rs1, rs2, rd, from_kernel);
+ return (fetch_reg(rs1, regs) + fetch_reg(rs2, regs));
+ }
+}
+
+/* This is just to make gcc think die_if_kernel does return... */
+static void __used unaligned_panic(char *str, struct pt_regs *regs)
+{
+ die_if_kernel(str, regs);
+}
+
+extern int do_int_load(unsigned long *dest_reg, int size,
+ unsigned long *saddr, int is_signed, int asi);
+
+extern int __do_int_store(unsigned long *dst_addr, int size,
+ unsigned long src_val, int asi);
+
+static inline int do_int_store(int reg_num, int size, unsigned long *dst_addr,
+ struct pt_regs *regs, int asi, int orig_asi)
+{
+ unsigned long zero = 0;
+ unsigned long *src_val_p = &zero;
+ unsigned long src_val;
+
+ if (size == 16) {
+ size = 8;
+ zero = (((long)(reg_num ?
+ (unsigned)fetch_reg(reg_num, regs) : 0)) << 32) |
+ (unsigned)fetch_reg(reg_num + 1, regs);
+ } else if (reg_num) {
+ src_val_p = fetch_reg_addr(reg_num, regs);
+ }
+ src_val = *src_val_p;
+ if (unlikely(asi != orig_asi)) {
+ switch (size) {
+ case 2:
+ src_val = swab16(src_val);
+ break;
+ case 4:
+ src_val = swab32(src_val);
+ break;
+ case 8:
+ src_val = swab64(src_val);
+ break;
+ case 16:
+ default:
+ BUG();
+ break;
+ };
+ }
+ return __do_int_store(dst_addr, size, src_val, asi);
+}
+
+static inline void advance(struct pt_regs *regs)
+{
+ regs->tpc = regs->tnpc;
+ regs->tnpc += 4;
+ if (test_thread_flag(TIF_32BIT)) {
+ regs->tpc &= 0xffffffff;
+ regs->tnpc &= 0xffffffff;
+ }
+}
+
+static inline int floating_point_load_or_store_p(unsigned int insn)
+{
+ return (insn >> 24) & 1;
+}
+
+static inline int ok_for_kernel(unsigned int insn)
+{
+ return !floating_point_load_or_store_p(insn);
+}
+
+static void kernel_mna_trap_fault(int fixup_tstate_asi)
+{
+ struct pt_regs *regs = current_thread_info()->kern_una_regs;
+ unsigned int insn = current_thread_info()->kern_una_insn;
+ const struct exception_table_entry *entry;
+
+ entry = search_exception_tables(regs->tpc);
+ if (!entry) {
+ unsigned long address;
+
+ address = compute_effective_address(regs, insn,
+ ((insn >> 25) & 0x1f));
+ if (address < PAGE_SIZE) {
+ printk(KERN_ALERT "Unable to handle kernel NULL "
+ "pointer dereference in mna handler");
+ } else
+ printk(KERN_ALERT "Unable to handle kernel paging "
+ "request in mna handler");
+ printk(KERN_ALERT " at virtual address %016lx\n",address);
+ printk(KERN_ALERT "current->{active_,}mm->context = %016lx\n",
+ (current->mm ? CTX_HWBITS(current->mm->context) :
+ CTX_HWBITS(current->active_mm->context)));
+ printk(KERN_ALERT "current->{active_,}mm->pgd = %016lx\n",
+ (current->mm ? (unsigned long) current->mm->pgd :
+ (unsigned long) current->active_mm->pgd));
+ die_if_kernel("Oops", regs);
+ /* Not reached */
+ }
+ regs->tpc = entry->fixup;
+ regs->tnpc = regs->tpc + 4;
+
+ if (fixup_tstate_asi) {
+ regs->tstate &= ~TSTATE_ASI;
+ regs->tstate |= (ASI_AIUS << 24UL);
+ }
+}
+
+static void log_unaligned(struct pt_regs *regs)
+{
+ static unsigned long count, last_time;
+
+ if (time_after(jiffies, last_time + 5 * HZ))
+ count = 0;
+ if (count < 5) {
+ last_time = jiffies;
+ count++;
+ printk("Kernel unaligned access at TPC[%lx] %pS\n",
+ regs->tpc, (void *) regs->tpc);
+ }
+}
+
+asmlinkage void kernel_unaligned_trap(struct pt_regs *regs, unsigned int insn)
+{
+ enum direction dir = decode_direction(insn);
+ int size = decode_access_size(insn);
+ int orig_asi, asi;
+
+ current_thread_info()->kern_una_regs = regs;
+ current_thread_info()->kern_una_insn = insn;
+
+ orig_asi = asi = decode_asi(insn, regs);
+
+ /* If this is a {get,put}_user() on an unaligned userspace pointer,
+ * just signal a fault and do not log the event.
+ */
+ if (asi == ASI_AIUS) {
+ kernel_mna_trap_fault(0);
+ return;
+ }
+
+ log_unaligned(regs);
+
+ if (!ok_for_kernel(insn) || dir == both) {
+ printk("Unsupported unaligned load/store trap for kernel "
+ "at <%016lx>.\n", regs->tpc);
+ unaligned_panic("Kernel does fpu/atomic "
+ "unaligned load/store.", regs);
+
+ kernel_mna_trap_fault(0);
+ } else {
+ unsigned long addr, *reg_addr;
+ int err;
+
+ addr = compute_effective_address(regs, insn,
+ ((insn >> 25) & 0x1f));
+#ifdef DEBUG_MNA
+ printk("KMNA: pc=%016lx [dir=%s addr=%016lx size=%d] "
+ "retpc[%016lx]\n",
+ regs->tpc, dirstrings[dir], addr, size,
+ regs->u_regs[UREG_RETPC]);
+#endif
+ switch (asi) {
+ case ASI_NL:
+ case ASI_AIUPL:
+ case ASI_AIUSL:
+ case ASI_PL:
+ case ASI_SL:
+ case ASI_PNFL:
+ case ASI_SNFL:
+ asi &= ~0x08;
+ break;
+ };
+ switch (dir) {
+ case load:
+ reg_addr = fetch_reg_addr(((insn>>25)&0x1f), regs);
+ err = do_int_load(reg_addr, size,
+ (unsigned long *) addr,
+ decode_signedness(insn), asi);
+ if (likely(!err) && unlikely(asi != orig_asi)) {
+ unsigned long val_in = *reg_addr;
+ switch (size) {
+ case 2:
+ val_in = swab16(val_in);
+ break;
+ case 4:
+ val_in = swab32(val_in);
+ break;
+ case 8:
+ val_in = swab64(val_in);
+ break;
+ case 16:
+ default:
+ BUG();
+ break;
+ };
+ *reg_addr = val_in;
+ }
+ break;
+
+ case store:
+ err = do_int_store(((insn>>25)&0x1f), size,
+ (unsigned long *) addr, regs,
+ asi, orig_asi);
+ break;
+
+ default:
+ panic("Impossible kernel unaligned trap.");
+ /* Not reached... */
+ }
+ if (unlikely(err))
+ kernel_mna_trap_fault(1);
+ else
+ advance(regs);
+ }
+}
+
+static char popc_helper[] = {
+0, 1, 1, 2, 1, 2, 2, 3,
+1, 2, 2, 3, 2, 3, 3, 4,
+};
+
+int handle_popc(u32 insn, struct pt_regs *regs)
+{
+ u64 value;
+ int ret, i, rd = ((insn >> 25) & 0x1f);
+ int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
+
+ if (insn & 0x2000) {
+ maybe_flush_windows(0, 0, rd, from_kernel);
+ value = sign_extend_imm13(insn);
+ } else {
+ maybe_flush_windows(0, insn & 0x1f, rd, from_kernel);
+ value = fetch_reg(insn & 0x1f, regs);
+ }
+ for (ret = 0, i = 0; i < 16; i++) {
+ ret += popc_helper[value & 0xf];
+ value >>= 4;
+ }
+ if (rd < 16) {
+ if (rd)
+ regs->u_regs[rd] = ret;
+ } else {
+ if (test_thread_flag(TIF_32BIT)) {
+ struct reg_window32 __user *win32;
+ win32 = (struct reg_window32 __user *)((unsigned long)((u32)regs->u_regs[UREG_FP]));
+ put_user(ret, &win32->locals[rd - 16]);
+ } else {
+ struct reg_window __user *win;
+ win = (struct reg_window __user *)(regs->u_regs[UREG_FP] + STACK_BIAS);
+ put_user(ret, &win->locals[rd - 16]);
+ }
+ }
+ advance(regs);
+ return 1;
+}
+
+extern void do_fpother(struct pt_regs *regs);
+extern void do_privact(struct pt_regs *regs);
+extern void spitfire_data_access_exception(struct pt_regs *regs,
+ unsigned long sfsr,
+ unsigned long sfar);
+extern void sun4v_data_access_exception(struct pt_regs *regs,
+ unsigned long addr,
+ unsigned long type_ctx);
+
+int handle_ldf_stq(u32 insn, struct pt_regs *regs)
+{
+ unsigned long addr = compute_effective_address(regs, insn, 0);
+ int freg = ((insn >> 25) & 0x1e) | ((insn >> 20) & 0x20);
+ struct fpustate *f = FPUSTATE;
+ int asi = decode_asi(insn, regs);
+ int flag = (freg < 32) ? FPRS_DL : FPRS_DU;
+
+ save_and_clear_fpu();
+ current_thread_info()->xfsr[0] &= ~0x1c000;
+ if (freg & 3) {
+ current_thread_info()->xfsr[0] |= (6 << 14) /* invalid_fp_register */;
+ do_fpother(regs);
+ return 0;
+ }
+ if (insn & 0x200000) {
+ /* STQ */
+ u64 first = 0, second = 0;
+
+ if (current_thread_info()->fpsaved[0] & flag) {
+ first = *(u64 *)&f->regs[freg];
+ second = *(u64 *)&f->regs[freg+2];
+ }
+ if (asi < 0x80) {
+ do_privact(regs);
+ return 1;
+ }
+ switch (asi) {
+ case ASI_P:
+ case ASI_S: break;
+ case ASI_PL:
+ case ASI_SL:
+ {
+ /* Need to convert endians */
+ u64 tmp = __swab64p(&first);
+
+ first = __swab64p(&second);
+ second = tmp;
+ break;
+ }
+ default:
+ if (tlb_type == hypervisor)
+ sun4v_data_access_exception(regs, addr, 0);
+ else
+ spitfire_data_access_exception(regs, 0, addr);
+ return 1;
+ }
+ if (put_user (first >> 32, (u32 __user *)addr) ||
+ __put_user ((u32)first, (u32 __user *)(addr + 4)) ||
+ __put_user (second >> 32, (u32 __user *)(addr + 8)) ||
+ __put_user ((u32)second, (u32 __user *)(addr + 12))) {
+ if (tlb_type == hypervisor)
+ sun4v_data_access_exception(regs, addr, 0);
+ else
+ spitfire_data_access_exception(regs, 0, addr);
+ return 1;
+ }
+ } else {
+ /* LDF, LDDF, LDQF */
+ u32 data[4] __attribute__ ((aligned(8)));
+ int size, i;
+ int err;
+
+ if (asi < 0x80) {
+ do_privact(regs);
+ return 1;
+ } else if (asi > ASI_SNFL) {
+ if (tlb_type == hypervisor)
+ sun4v_data_access_exception(regs, addr, 0);
+ else
+ spitfire_data_access_exception(regs, 0, addr);
+ return 1;
+ }
+ switch (insn & 0x180000) {
+ case 0x000000: size = 1; break;
+ case 0x100000: size = 4; break;
+ default: size = 2; break;
+ }
+ for (i = 0; i < size; i++)
+ data[i] = 0;
+
+ err = get_user (data[0], (u32 __user *) addr);
+ if (!err) {
+ for (i = 1; i < size; i++)
+ err |= __get_user (data[i], (u32 __user *)(addr + 4*i));
+ }
+ if (err && !(asi & 0x2 /* NF */)) {
+ if (tlb_type == hypervisor)
+ sun4v_data_access_exception(regs, addr, 0);
+ else
+ spitfire_data_access_exception(regs, 0, addr);
+ return 1;
+ }
+ if (asi & 0x8) /* Little */ {
+ u64 tmp;
+
+ switch (size) {
+ case 1: data[0] = le32_to_cpup(data + 0); break;
+ default:*(u64 *)(data + 0) = le64_to_cpup((u64 *)(data + 0));
+ break;
+ case 4: tmp = le64_to_cpup((u64 *)(data + 0));
+ *(u64 *)(data + 0) = le64_to_cpup((u64 *)(data + 2));
+ *(u64 *)(data + 2) = tmp;
+ break;
+ }
+ }
+ if (!(current_thread_info()->fpsaved[0] & FPRS_FEF)) {
+ current_thread_info()->fpsaved[0] = FPRS_FEF;
+ current_thread_info()->gsr[0] = 0;
+ }
+ if (!(current_thread_info()->fpsaved[0] & flag)) {
+ if (freg < 32)
+ memset(f->regs, 0, 32*sizeof(u32));
+ else
+ memset(f->regs+32, 0, 32*sizeof(u32));
+ }
+ memcpy(f->regs + freg, data, size * 4);
+ current_thread_info()->fpsaved[0] |= flag;
+ }
+ advance(regs);
+ return 1;
+}
+
+void handle_ld_nf(u32 insn, struct pt_regs *regs)
+{
+ int rd = ((insn >> 25) & 0x1f);
+ int from_kernel = (regs->tstate & TSTATE_PRIV) != 0;
+ unsigned long *reg;
+
+ maybe_flush_windows(0, 0, rd, from_kernel);
+ reg = fetch_reg_addr(rd, regs);
+ if (from_kernel || rd < 16) {
+ reg[0] = 0;
+ if ((insn & 0x780000) == 0x180000)
+ reg[1] = 0;
+ } else if (test_thread_flag(TIF_32BIT)) {
+ put_user(0, (int __user *) reg);
+ if ((insn & 0x780000) == 0x180000)
+ put_user(0, ((int __user *) reg) + 1);
+ } else {
+ put_user(0, (unsigned long __user *) reg);
+ if ((insn & 0x780000) == 0x180000)
+ put_user(0, (unsigned long __user *) reg + 1);
+ }
+ advance(regs);
+}
+
+void handle_lddfmna(struct pt_regs *regs, unsigned long sfar, unsigned long sfsr)
+{
+ unsigned long pc = regs->tpc;
+ unsigned long tstate = regs->tstate;
+ u32 insn;
+ u64 value;
+ u8 freg;
+ int flag;
+ struct fpustate *f = FPUSTATE;
+
+ if (tstate & TSTATE_PRIV)
+ die_if_kernel("lddfmna from kernel", regs);
+ if (test_thread_flag(TIF_32BIT))
+ pc = (u32)pc;
+ if (get_user(insn, (u32 __user *) pc) != -EFAULT) {
+ int asi = decode_asi(insn, regs);
+ u32 first, second;
+ int err;
+
+ if ((asi > ASI_SNFL) ||
+ (asi < ASI_P))
+ goto daex;
+ first = second = 0;
+ err = get_user(first, (u32 __user *)sfar);
+ if (!err)
+ err = get_user(second, (u32 __user *)(sfar + 4));
+ if (err) {
+ if (!(asi & 0x2))
+ goto daex;
+ first = second = 0;
+ }
+ save_and_clear_fpu();
+ freg = ((insn >> 25) & 0x1e) | ((insn >> 20) & 0x20);
+ value = (((u64)first) << 32) | second;
+ if (asi & 0x8) /* Little */
+ value = __swab64p(&value);
+ flag = (freg < 32) ? FPRS_DL : FPRS_DU;
+ if (!(current_thread_info()->fpsaved[0] & FPRS_FEF)) {
+ current_thread_info()->fpsaved[0] = FPRS_FEF;
+ current_thread_info()->gsr[0] = 0;
+ }
+ if (!(current_thread_info()->fpsaved[0] & flag)) {
+ if (freg < 32)
+ memset(f->regs, 0, 32*sizeof(u32));
+ else
+ memset(f->regs+32, 0, 32*sizeof(u32));
+ }
+ *(u64 *)(f->regs + freg) = value;
+ current_thread_info()->fpsaved[0] |= flag;
+ } else {
+daex:
+ if (tlb_type == hypervisor)
+ sun4v_data_access_exception(regs, sfar, sfsr);
+ else
+ spitfire_data_access_exception(regs, sfsr, sfar);
+ return;
+ }
+ advance(regs);
+ return;
+}
+
+void handle_stdfmna(struct pt_regs *regs, unsigned long sfar, unsigned long sfsr)
+{
+ unsigned long pc = regs->tpc;
+ unsigned long tstate = regs->tstate;
+ u32 insn;
+ u64 value;
+ u8 freg;
+ int flag;
+ struct fpustate *f = FPUSTATE;
+
+ if (tstate & TSTATE_PRIV)
+ die_if_kernel("stdfmna from kernel", regs);
+ if (test_thread_flag(TIF_32BIT))
+ pc = (u32)pc;
+ if (get_user(insn, (u32 __user *) pc) != -EFAULT) {
+ int asi = decode_asi(insn, regs);
+ freg = ((insn >> 25) & 0x1e) | ((insn >> 20) & 0x20);
+ value = 0;
+ flag = (freg < 32) ? FPRS_DL : FPRS_DU;
+ if ((asi > ASI_SNFL) ||
+ (asi < ASI_P))
+ goto daex;
+ save_and_clear_fpu();
+ if (current_thread_info()->fpsaved[0] & flag)
+ value = *(u64 *)&f->regs[freg];
+ switch (asi) {
+ case ASI_P:
+ case ASI_S: break;
+ case ASI_PL:
+ case ASI_SL:
+ value = __swab64p(&value); break;
+ default: goto daex;
+ }
+ if (put_user (value >> 32, (u32 __user *) sfar) ||
+ __put_user ((u32)value, (u32 __user *)(sfar + 4)))
+ goto daex;
+ } else {
+daex:
+ if (tlb_type == hypervisor)
+ sun4v_data_access_exception(regs, sfar, sfsr);
+ else
+ spitfire_data_access_exception(regs, sfsr, sfar);
+ return;
+ }
+ advance(regs);
+ return;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-21 13:17:52 +0000