Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 364 insertions, 0 deletions

diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c
new file mode 100644
index 0000000..6e70c42
--- /dev/null
+++ b/arch/mips/kernel/process.c
@@ -0,0 +1,364 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1994 - 1999, 2000 by Ralf Baechle and others.
+ * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ * Copyright (C) 2004 Thiemo Seufer
+ */
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/stddef.h>
+#include <linux/unistd.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/mman.h>
+#include <linux/personality.h>
+#include <linux/sys.h>
+#include <linux/user.h>
+#include <linux/a.out.h>
+#include <linux/init.h>
+#include <linux/completion.h>
+
+#include <asm/bootinfo.h>
+#include <asm/cpu.h>
+#include <asm/fpu.h>
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/mipsregs.h>
+#include <asm/processor.h>
+#include <asm/uaccess.h>
+#include <asm/io.h>
+#include <asm/elf.h>
+#include <asm/isadep.h>
+#include <asm/inst.h>
+
+/*
+ * We use this if we don't have any better idle routine..
+ * (This to kill: kernel/platform.c.
+ */
+void default_idle (void)
+{
+}
+
+/*
+ * The idle thread. There's no useful work to be done, so just try to conserve
+ * power and have a low exit latency (ie sit in a loop waiting for somebody to
+ * say that they'd like to reschedule)
+ */
+ATTRIB_NORET void cpu_idle(void)
+{
+	/* endless idle loop with no priority at all */
+	while (1) {
+		while (!need_resched())
+			if (cpu_wait)
+				(*cpu_wait)();
+		schedule();
+	}
+}
+
+asmlinkage void ret_from_fork(void);
+
+void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp)
+{
+	unsigned long status;
+
+	/* New thread loses kernel privileges. */
+	status = regs->cp0_status & ~(ST0_CU0|ST0_CU1|KU_MASK);
+#ifdef CONFIG_MIPS64
+	status &= ~ST0_FR;
+	status |= (current->thread.mflags & MF_32BIT_REGS) ? 0 : ST0_FR;
+#endif
+	status |= KU_USER;
+	regs->cp0_status = status;
+	clear_used_math();
+	lose_fpu();
+	regs->cp0_epc = pc;
+	regs->regs[29] = sp;
+	current_thread_info()->addr_limit = USER_DS;
+}
+
+void exit_thread(void)
+{
+}
+
+void flush_thread(void)
+{
+}
+
+int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
+	unsigned long unused, struct task_struct *p, struct pt_regs *regs)
+{
+	struct thread_info *ti = p->thread_info;
+	struct pt_regs *childregs;
+	long childksp;
+
+	childksp = (unsigned long)ti + THREAD_SIZE - 32;
+
+	preempt_disable();
+
+	if (is_fpu_owner()) {
+		save_fp(p);
+	}
+
+	preempt_enable();
+
+	/* set up new TSS. */
+	childregs = (struct pt_regs *) childksp - 1;
+	*childregs = *regs;
+	childregs->regs[7] = 0;	/* Clear error flag */
+
+#if defined(CONFIG_BINFMT_IRIX)
+	if (current->personality != PER_LINUX) {
+		/* Under IRIX things are a little different. */
+		childregs->regs[3] = 1;
+		regs->regs[3] = 0;
+	}
+#endif
+	childregs->regs[2] = 0;	/* Child gets zero as return value */
+	regs->regs[2] = p->pid;
+
+	if (childregs->cp0_status & ST0_CU0) {
+		childregs->regs[28] = (unsigned long) ti;
+		childregs->regs[29] = childksp;
+		ti->addr_limit = KERNEL_DS;
+	} else {
+		childregs->regs[29] = usp;
+		ti->addr_limit = USER_DS;
+	}
+	p->thread.reg29 = (unsigned long) childregs;
+	p->thread.reg31 = (unsigned long) ret_from_fork;
+
+	/*
+	 * New tasks lose permission to use the fpu. This accelerates context
+	 * switching for most programs since they don't use the fpu.
+	 */
+	p->thread.cp0_status = read_c0_status() & ~(ST0_CU2|ST0_CU1);
+	childregs->cp0_status &= ~(ST0_CU2|ST0_CU1);
+	clear_tsk_thread_flag(p, TIF_USEDFPU);
+
+	return 0;
+}
+
+/* Fill in the fpu structure for a core dump.. */
+int dump_fpu(struct pt_regs *regs, elf_fpregset_t *r)
+{
+	memcpy(r, &current->thread.fpu, sizeof(current->thread.fpu));
+
+	return 1;
+}
+
+void dump_regs(elf_greg_t *gp, struct pt_regs *regs)
+{
+	int i;
+
+	for (i = 0; i < EF_R0; i++)
+		gp[i] = 0;
+	gp[EF_R0] = 0;
+	for (i = 1; i <= 31; i++)
+		gp[EF_R0 + i] = regs->regs[i];
+	gp[EF_R26] = 0;
+	gp[EF_R27] = 0;
+	gp[EF_LO] = regs->lo;
+	gp[EF_HI] = regs->hi;
+	gp[EF_CP0_EPC] = regs->cp0_epc;
+	gp[EF_CP0_BADVADDR] = regs->cp0_badvaddr;
+	gp[EF_CP0_STATUS] = regs->cp0_status;
+	gp[EF_CP0_CAUSE] = regs->cp0_cause;
+#ifdef EF_UNUSED0
+	gp[EF_UNUSED0] = 0;
+#endif
+}
+
+int dump_task_fpu (struct task_struct *t, elf_fpregset_t *fpr)
+{
+	memcpy(fpr, &t->thread.fpu, sizeof(current->thread.fpu));
+
+	return 1;
+}
+
+/*
+ * Create a kernel thread
+ */
+ATTRIB_NORET void kernel_thread_helper(void *arg, int (*fn)(void *))
+{
+	do_exit(fn(arg));
+}
+
+long kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
+{
+	struct pt_regs regs;
+
+	memset(&regs, 0, sizeof(regs));
+
+	regs.regs[4] = (unsigned long) arg;
+	regs.regs[5] = (unsigned long) fn;
+	regs.cp0_epc = (unsigned long) kernel_thread_helper;
+	regs.cp0_status = read_c0_status();
+#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
+	regs.cp0_status &= ~(ST0_KUP | ST0_IEC);
+	regs.cp0_status |= ST0_IEP;
+#else
+	regs.cp0_status |= ST0_EXL;
+#endif
+
+	/* Ok, create the new process.. */
+	return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
+}
+
+struct mips_frame_info {
+	int frame_offset;
+	int pc_offset;
+};
+static struct mips_frame_info schedule_frame;
+static struct mips_frame_info schedule_timeout_frame;
+static struct mips_frame_info sleep_on_frame;
+static struct mips_frame_info sleep_on_timeout_frame;
+static struct mips_frame_info wait_for_completion_frame;
+static int mips_frame_info_initialized;
+static int __init get_frame_info(struct mips_frame_info *info, void *func)
+{
+	int i;
+	union mips_instruction *ip = (union mips_instruction *)func;
+	info->pc_offset = -1;
+	info->frame_offset = -1;
+	for (i = 0; i < 128; i++, ip++) {
+		/* if jal, jalr, jr, stop. */
+		if (ip->j_format.opcode == jal_op ||
+		    (ip->r_format.opcode == spec_op &&
+		     (ip->r_format.func == jalr_op ||
+		      ip->r_format.func == jr_op)))
+			break;
+
+		if (
+#ifdef CONFIG_MIPS32
+		    ip->i_format.opcode == sw_op &&
+#endif
+#ifdef CONFIG_MIPS64
+		    ip->i_format.opcode == sd_op &&
+#endif
+		    ip->i_format.rs == 29)
+		{
+			/* sw / sd $ra, offset($sp) */
+			if (ip->i_format.rt == 31) {
+				if (info->pc_offset != -1)
+					break;
+				info->pc_offset =
+					ip->i_format.simmediate / sizeof(long);
+			}
+			/* sw / sd $s8, offset($sp) */
+			if (ip->i_format.rt == 30) {
+				if (info->frame_offset != -1)
+					break;
+				info->frame_offset =
+					ip->i_format.simmediate / sizeof(long);
+			}
+		}
+	}
+	if (info->pc_offset == -1 || info->frame_offset == -1) {
+		printk("Can't analyze prologue code at %p\n", func);
+		info->pc_offset = -1;
+		info->frame_offset = -1;
+		return -1;
+	}
+
+	return 0;
+}
+
+static int __init frame_info_init(void)
+{
+	mips_frame_info_initialized =
+		!get_frame_info(&schedule_frame, schedule) &&
+		!get_frame_info(&schedule_timeout_frame, schedule_timeout) &&
+		!get_frame_info(&sleep_on_frame, sleep_on) &&
+		!get_frame_info(&sleep_on_timeout_frame, sleep_on_timeout) &&
+		!get_frame_info(&wait_for_completion_frame, wait_for_completion);
+
+	return 0;
+}
+
+arch_initcall(frame_info_init);
+
+/*
+ * Return saved PC of a blocked thread.
+ */
+unsigned long thread_saved_pc(struct task_struct *tsk)
+{
+	struct thread_struct *t = &tsk->thread;
+
+	/* New born processes are a special case */
+	if (t->reg31 == (unsigned long) ret_from_fork)
+		return t->reg31;
+
+	if (schedule_frame.pc_offset < 0)
+		return 0;
+	return ((unsigned long *)t->reg29)[schedule_frame.pc_offset];
+}
+
+/* get_wchan - a maintenance nightmare^W^Wpain in the ass ...  */
+unsigned long get_wchan(struct task_struct *p)
+{
+	unsigned long frame, pc;
+
+	if (!p || p == current || p->state == TASK_RUNNING)
+		return 0;
+
+	if (!mips_frame_info_initialized)
+		return 0;
+	pc = thread_saved_pc(p);
+	if (!in_sched_functions(pc))
+		goto out;
+
+	if (pc >= (unsigned long) sleep_on_timeout)
+		goto schedule_timeout_caller;
+	if (pc >= (unsigned long) sleep_on)
+		goto schedule_caller;
+	if (pc >= (unsigned long) interruptible_sleep_on_timeout)
+		goto schedule_timeout_caller;
+	if (pc >= (unsigned long)interruptible_sleep_on)
+		goto schedule_caller;
+	if (pc >= (unsigned long)wait_for_completion)
+		goto schedule_caller;
+	goto schedule_timeout_caller;
+
+schedule_caller:
+	frame = ((unsigned long *)p->thread.reg30)[schedule_frame.frame_offset];
+	if (pc >= (unsigned long) sleep_on)
+		pc = ((unsigned long *)frame)[sleep_on_frame.pc_offset];
+	else
+		pc = ((unsigned long *)frame)[wait_for_completion_frame.pc_offset];
+	goto out;
+
+schedule_timeout_caller:
+	/*
+	 * The schedule_timeout frame
+	 */
+	frame = ((unsigned long *)p->thread.reg30)[schedule_frame.frame_offset];
+
+	/*
+	 * frame now points to sleep_on_timeout's frame
+	 */
+	pc    = ((unsigned long *)frame)[schedule_timeout_frame.pc_offset];
+
+	if (in_sched_functions(pc)) {
+		/* schedule_timeout called by [interruptible_]sleep_on_timeout */
+		frame = ((unsigned long *)frame)[schedule_timeout_frame.frame_offset];
+		pc    = ((unsigned long *)frame)[sleep_on_timeout_frame.pc_offset];
+	}
+
+out:
+
+#ifdef CONFIG_MIPS64
+	if (current->thread.mflags & MF_32BIT_REGS) /* Kludge for 32-bit ps  */
+		pc &= 0xffffffffUL;
+#endif
+
+	return pc;
+}
+
+EXPORT_SYMBOL(get_wchan);