Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 282 insertions, 0 deletions

diff --git a/arch/sparc/kernel/unaligned_32.c b/arch/sparc/kernel/unaligned_32.c
new file mode 100644
index 000000000..455f0258c
--- /dev/null
+++ b/arch/sparc/kernel/unaligned_32.c
@@ -0,0 +1,282 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * unaligned.c: Unaligned load/store trap handling with special
+ *              cases for the kernel to do them more quickly.
+ *
+ * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
+ * Copyright (C) 1996 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ */
+
+
+#include <linux/kernel.h>
+#include <linux/sched/signal.h>
+#include <linux/mm.h>
+#include <asm/ptrace.h>
+#include <asm/processor.h>
+#include <linux/uaccess.h>
+#include <linux/smp.h>
+#include <linux/perf_event.h>
+#include <linux/extable.h>
+
+#include <asm/setup.h>
+
+#include "kernel.h"
+
+enum direction {
+	load,    /* ld, ldd, ldh, ldsh */
+	store,   /* st, std, sth, stsh */
+	both,    /* Swap, ldstub, etc. */
+	fpload,
+	fpstore,
+	invalid,
+};
+
+static inline enum direction decode_direction(unsigned int insn)
+{
+	unsigned long tmp = (insn >> 21) & 1;
+
+	if(!tmp)
+		return load;
+	else {
+		if(((insn>>19)&0x3f) == 15)
+			return both;
+		else
+			return store;
+	}
+}
+
+/* 8 = double-word, 4 = word, 2 = half-word */
+static inline int decode_access_size(unsigned int insn)
+{
+	insn = (insn >> 19) & 3;
+
+	if(!insn)
+		return 4;
+	else if(insn == 3)
+		return 8;
+	else if(insn == 2)
+		return 2;
+	else {
+		printk("Impossible unaligned trap. insn=%08x\n", insn);
+		die_if_kernel("Byte sized unaligned access?!?!", current->thread.kregs);
+		return 4; /* just to keep gcc happy. */
+	}
+}
+
+/* 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)
+{
+	if(rs2 >= 16 || rs1 >= 16 || rd >= 16) {
+		/* Wheee... */
+		__asm__ __volatile__("save %sp, -0x40, %sp\n\t"
+				     "save %sp, -0x40, %sp\n\t"
+				     "save %sp, -0x40, %sp\n\t"
+				     "save %sp, -0x40, %sp\n\t"
+				     "save %sp, -0x40, %sp\n\t"
+				     "save %sp, -0x40, %sp\n\t"
+				     "save %sp, -0x40, %sp\n\t"
+				     "restore; restore; restore; restore;\n\t"
+				     "restore; restore; restore;\n\t");
+	}
+}
+
+static inline int sign_extend_imm13(int imm)
+{
+	return imm << 19 >> 19;
+}
+
+static inline unsigned long fetch_reg(unsigned int reg, struct pt_regs *regs)
+{
+	struct reg_window32 *win;
+
+	if(reg < 16)
+		return (!reg ? 0 : regs->u_regs[reg]);
+
+	/* Ho hum, the slightly complicated case. */
+	win = (struct reg_window32 *) regs->u_regs[UREG_FP];
+	return win->locals[reg - 16]; /* yes, I know what this does... */
+}
+
+static inline unsigned long safe_fetch_reg(unsigned int reg, struct pt_regs *regs)
+{
+	struct reg_window32 __user *win;
+	unsigned long ret;
+
+	if (reg < 16)
+		return (!reg ? 0 : regs->u_regs[reg]);
+
+	/* Ho hum, the slightly complicated case. */
+	win = (struct reg_window32 __user *) regs->u_regs[UREG_FP];
+
+	if ((unsigned long)win & 3)
+		return -1;
+
+	if (get_user(ret, &win->locals[reg - 16]))
+		return -1;
+
+	return ret;
+}
+
+static inline unsigned long *fetch_reg_addr(unsigned int reg, struct pt_regs *regs)
+{
+	struct reg_window32 *win;
+
+	if(reg < 16)
+		return &regs->u_regs[reg];
+	win = (struct reg_window32 *) regs->u_regs[UREG_FP];
+	return &win->locals[reg - 16];
+}
+
+static unsigned long compute_effective_address(struct pt_regs *regs,
+					       unsigned int insn)
+{
+	unsigned int rs1 = (insn >> 14) & 0x1f;
+	unsigned int rs2 = insn & 0x1f;
+	unsigned int rd = (insn >> 25) & 0x1f;
+
+	if(insn & 0x2000) {
+		maybe_flush_windows(rs1, 0, rd);
+		return (fetch_reg(rs1, regs) + sign_extend_imm13(insn));
+	} else {
+		maybe_flush_windows(rs1, rs2, rd);
+		return (fetch_reg(rs1, regs) + fetch_reg(rs2, regs));
+	}
+}
+
+unsigned long safe_compute_effective_address(struct pt_regs *regs,
+					     unsigned int insn)
+{
+	unsigned int rs1 = (insn >> 14) & 0x1f;
+	unsigned int rs2 = insn & 0x1f;
+	unsigned int rd = (insn >> 25) & 0x1f;
+
+	if(insn & 0x2000) {
+		maybe_flush_windows(rs1, 0, rd);
+		return (safe_fetch_reg(rs1, regs) + sign_extend_imm13(insn));
+	} else {
+		maybe_flush_windows(rs1, rs2, rd);
+		return (safe_fetch_reg(rs1, regs) + safe_fetch_reg(rs2, regs));
+	}
+}
+
+/* This is just to make gcc think panic does return... */
+static void unaligned_panic(char *str)
+{
+	panic("%s", str);
+}
+
+/* una_asm.S */
+extern int do_int_load(unsigned long *dest_reg, int size,
+		       unsigned long *saddr, int is_signed);
+extern int __do_int_store(unsigned long *dst_addr, int size,
+			  unsigned long *src_val);
+
+static int do_int_store(int reg_num, int size, unsigned long *dst_addr,
+			struct pt_regs *regs)
+{
+	unsigned long zero[2] = { 0, 0 };
+	unsigned long *src_val;
+
+	if (reg_num)
+		src_val = fetch_reg_addr(reg_num, regs);
+	else {
+		src_val = &zero[0];
+		if (size == 8)
+			zero[1] = fetch_reg(1, regs);
+	}
+	return __do_int_store(dst_addr, size, src_val);
+}
+
+extern void smp_capture(void);
+extern void smp_release(void);
+
+static inline void advance(struct pt_regs *regs)
+{
+	regs->pc   = regs->npc;
+	regs->npc += 4;
+}
+
+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(struct pt_regs *regs, unsigned int insn)
+{
+	const struct exception_table_entry *entry;
+
+	entry = search_exception_tables(regs->pc);
+	if (!entry) {
+		unsigned long address = compute_effective_address(regs, insn);
+        	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 %08lx\n",address);
+		printk(KERN_ALERT "current->{mm,active_mm}->context = %08lx\n",
+			(current->mm ? current->mm->context :
+			current->active_mm->context));
+		printk(KERN_ALERT "current->{mm,active_mm}->pgd = %08lx\n",
+			(current->mm ? (unsigned long) current->mm->pgd :
+			(unsigned long) current->active_mm->pgd));
+	        die_if_kernel("Oops", regs);
+		/* Not reached */
+	}
+	regs->pc = entry->fixup;
+	regs->npc = regs->pc + 4;
+}
+
+asmlinkage void kernel_unaligned_trap(struct pt_regs *regs, unsigned int insn)
+{
+	enum direction dir = decode_direction(insn);
+	int size = decode_access_size(insn);
+
+	if(!ok_for_kernel(insn) || dir == both) {
+		printk("Unsupported unaligned load/store trap for kernel at <%08lx>.\n",
+		       regs->pc);
+		unaligned_panic("Wheee. Kernel does fpu/atomic unaligned load/store.");
+	} else {
+		unsigned long addr = compute_effective_address(regs, insn);
+		int err;
+
+		perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, addr);
+		switch (dir) {
+		case load:
+			err = do_int_load(fetch_reg_addr(((insn>>25)&0x1f),
+							 regs),
+					  size, (unsigned long *) addr,
+					  decode_signedness(insn));
+			break;
+
+		case store:
+			err = do_int_store(((insn>>25)&0x1f), size,
+					   (unsigned long *) addr, regs);
+			break;
+		default:
+			panic("Impossible kernel unaligned trap.");
+			/* Not reached... */
+		}
+		if (err)
+			kernel_mna_trap_fault(regs, insn);
+		else
+			advance(regs);
+	}
+}
+
+asmlinkage void user_unaligned_trap(struct pt_regs *regs, unsigned int insn)
+{
+	send_sig_fault(SIGBUS, BUS_ADRALN,
+		       (void __user *)safe_compute_effective_address(regs, insn),
+		       current);
+}