summaryrefslogtreecommitdiffstats
path: root/arch/sh64/kernel/process.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/sh64/kernel/process.c')
-rw-r--r--arch/sh64/kernel/process.c962
1 files changed, 962 insertions, 0 deletions
diff --git a/arch/sh64/kernel/process.c b/arch/sh64/kernel/process.c
new file mode 100644
index 00000000000..efde41c0cd6
--- /dev/null
+++ b/arch/sh64/kernel/process.c
@@ -0,0 +1,962 @@
+/*
+ * 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.
+ *
+ * arch/sh64/kernel/process.c
+ *
+ * Copyright (C) 2000, 2001 Paolo Alberelli
+ * Copyright (C) 2003 Paul Mundt
+ * Copyright (C) 2003, 2004 Richard Curnow
+ *
+ * Started from SH3/4 version:
+ * Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
+ *
+ * In turn started from i386 version:
+ * Copyright (C) 1995 Linus Torvalds
+ *
+ */
+
+/*
+ * This file handles the architecture-dependent parts of process handling..
+ */
+
+/* Temporary flags/tests. All to be removed/undefined. BEGIN */
+#define IDLE_TRACE
+#define VM_SHOW_TABLES
+#define VM_TEST_FAULT
+#define VM_TEST_RTLBMISS
+#define VM_TEST_WTLBMISS
+
+#undef VM_SHOW_TABLES
+#undef IDLE_TRACE
+/* Temporary flags/tests. All to be removed/undefined. END */
+
+#define __KERNEL_SYSCALLS__
+#include <stdarg.h>
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/rwsem.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/user.h>
+#include <linux/a.out.h>
+#include <linux/interrupt.h>
+#include <linux/unistd.h>
+#include <linux/delay.h>
+#include <linux/reboot.h>
+#include <linux/init.h>
+
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/processor.h> /* includes also <asm/registers.h> */
+#include <asm/mmu_context.h>
+#include <asm/elf.h>
+#include <asm/page.h>
+
+#include <linux/irq.h>
+
+struct task_struct *last_task_used_math = NULL;
+
+#ifdef IDLE_TRACE
+#ifdef VM_SHOW_TABLES
+/* For testing */
+static void print_PTE(long base)
+{
+ int i, skip=0;
+ long long x, y, *p = (long long *) base;
+
+ for (i=0; i< 512; i++, p++){
+ if (*p == 0) {
+ if (!skip) {
+ skip++;
+ printk("(0s) ");
+ }
+ } else {
+ skip=0;
+ x = (*p) >> 32;
+ y = (*p) & 0xffffffff;
+ printk("%08Lx%08Lx ", x, y);
+ if (!((i+1)&0x3)) printk("\n");
+ }
+ }
+}
+
+/* For testing */
+static void print_DIR(long base)
+{
+ int i, skip=0;
+ long *p = (long *) base;
+
+ for (i=0; i< 512; i++, p++){
+ if (*p == 0) {
+ if (!skip) {
+ skip++;
+ printk("(0s) ");
+ }
+ } else {
+ skip=0;
+ printk("%08lx ", *p);
+ if (!((i+1)&0x7)) printk("\n");
+ }
+ }
+}
+
+/* For testing */
+static void print_vmalloc_first_tables(void)
+{
+
+#define PRESENT 0x800 /* Bit 11 */
+
+ /*
+ * Do it really dirty by looking at raw addresses,
+ * raw offsets, no types. If we used pgtable/pgalloc
+ * macros/definitions we could hide potential bugs.
+ *
+ * Note that pointers are 32-bit for CDC.
+ */
+ long pgdt, pmdt, ptet;
+
+ pgdt = (long) &swapper_pg_dir;
+ printk("-->PGD (0x%08lx):\n", pgdt);
+ print_DIR(pgdt);
+ printk("\n");
+
+ /* VMALLOC pool is mapped at 0xc0000000, second (pointer) entry in PGD */
+ pgdt += 4;
+ pmdt = (long) (* (long *) pgdt);
+ if (!(pmdt & PRESENT)) {
+ printk("No PMD\n");
+ return;
+ } else pmdt &= 0xfffff000;
+
+ printk("-->PMD (0x%08lx):\n", pmdt);
+ print_DIR(pmdt);
+ printk("\n");
+
+ /* Get the pmdt displacement for 0xc0000000 */
+ pmdt += 2048;
+
+ /* just look at first two address ranges ... */
+ /* ... 0xc0000000 ... */
+ ptet = (long) (* (long *) pmdt);
+ if (!(ptet & PRESENT)) {
+ printk("No PTE0\n");
+ return;
+ } else ptet &= 0xfffff000;
+
+ printk("-->PTE0 (0x%08lx):\n", ptet);
+ print_PTE(ptet);
+ printk("\n");
+
+ /* ... 0xc0001000 ... */
+ ptet += 4;
+ if (!(ptet & PRESENT)) {
+ printk("No PTE1\n");
+ return;
+ } else ptet &= 0xfffff000;
+ printk("-->PTE1 (0x%08lx):\n", ptet);
+ print_PTE(ptet);
+ printk("\n");
+}
+#else
+#define print_vmalloc_first_tables()
+#endif /* VM_SHOW_TABLES */
+
+static void test_VM(void)
+{
+ void *a, *b, *c;
+
+#ifdef VM_SHOW_TABLES
+ printk("Initial PGD/PMD/PTE\n");
+#endif
+ print_vmalloc_first_tables();
+
+ printk("Allocating 2 bytes\n");
+ a = vmalloc(2);
+ print_vmalloc_first_tables();
+
+ printk("Allocating 4100 bytes\n");
+ b = vmalloc(4100);
+ print_vmalloc_first_tables();
+
+ printk("Allocating 20234 bytes\n");
+ c = vmalloc(20234);
+ print_vmalloc_first_tables();
+
+#ifdef VM_TEST_FAULT
+ /* Here you may want to fault ! */
+
+#ifdef VM_TEST_RTLBMISS
+ printk("Ready to fault upon read.\n");
+ if (* (char *) a) {
+ printk("RTLBMISSed on area a !\n");
+ }
+ printk("RTLBMISSed on area a !\n");
+#endif
+
+#ifdef VM_TEST_WTLBMISS
+ printk("Ready to fault upon write.\n");
+ *((char *) b) = 'L';
+ printk("WTLBMISSed on area b !\n");
+#endif
+
+#endif /* VM_TEST_FAULT */
+
+ printk("Deallocating the 4100 byte chunk\n");
+ vfree(b);
+ print_vmalloc_first_tables();
+
+ printk("Deallocating the 2 byte chunk\n");
+ vfree(a);
+ print_vmalloc_first_tables();
+
+ printk("Deallocating the last chunk\n");
+ vfree(c);
+ print_vmalloc_first_tables();
+}
+
+extern unsigned long volatile jiffies;
+int once = 0;
+unsigned long old_jiffies;
+int pid = -1, pgid = -1;
+
+void idle_trace(void)
+{
+
+ _syscall0(int, getpid)
+ _syscall1(int, getpgid, int, pid)
+
+ if (!once) {
+ /* VM allocation/deallocation simple test */
+ test_VM();
+ pid = getpid();
+
+ printk("Got all through to Idle !!\n");
+ printk("I'm now going to loop forever ...\n");
+ printk("Any ! below is a timer tick.\n");
+ printk("Any . below is a getpgid system call from pid = %d.\n", pid);
+
+
+ old_jiffies = jiffies;
+ once++;
+ }
+
+ if (old_jiffies != jiffies) {
+ old_jiffies = jiffies - old_jiffies;
+ switch (old_jiffies) {
+ case 1:
+ printk("!");
+ break;
+ case 2:
+ printk("!!");
+ break;
+ case 3:
+ printk("!!!");
+ break;
+ case 4:
+ printk("!!!!");
+ break;
+ default:
+ printk("(%d!)", (int) old_jiffies);
+ }
+ old_jiffies = jiffies;
+ }
+ pgid = getpgid(pid);
+ printk(".");
+}
+#else
+#define idle_trace() do { } while (0)
+#endif /* IDLE_TRACE */
+
+static int hlt_counter = 1;
+
+#define HARD_IDLE_TIMEOUT (HZ / 3)
+
+void disable_hlt(void)
+{
+ hlt_counter++;
+}
+
+void enable_hlt(void)
+{
+ hlt_counter--;
+}
+
+static int __init nohlt_setup(char *__unused)
+{
+ hlt_counter = 1;
+ return 1;
+}
+
+static int __init hlt_setup(char *__unused)
+{
+ hlt_counter = 0;
+ return 1;
+}
+
+__setup("nohlt", nohlt_setup);
+__setup("hlt", hlt_setup);
+
+static inline void hlt(void)
+{
+ if (hlt_counter)
+ return;
+
+ __asm__ __volatile__ ("sleep" : : : "memory");
+}
+
+/*
+ * The idle loop on a uniprocessor SH..
+ */
+void default_idle(void)
+{
+ /* endless idle loop with no priority at all */
+ while (1) {
+ if (hlt_counter) {
+ while (1)
+ if (need_resched())
+ break;
+ } else {
+ local_irq_disable();
+ while (!need_resched()) {
+ local_irq_enable();
+ idle_trace();
+ hlt();
+ local_irq_disable();
+ }
+ local_irq_enable();
+ }
+ schedule();
+ }
+}
+
+void cpu_idle(void)
+{
+ default_idle();
+}
+
+void machine_restart(char * __unused)
+{
+ extern void phys_stext(void);
+
+ phys_stext();
+}
+
+void machine_halt(void)
+{
+ for (;;);
+}
+
+void machine_power_off(void)
+{
+ extern void enter_deep_standby(void);
+
+ enter_deep_standby();
+}
+
+void show_regs(struct pt_regs * regs)
+{
+ unsigned long long ah, al, bh, bl, ch, cl;
+
+ printk("\n");
+
+ ah = (regs->pc) >> 32;
+ al = (regs->pc) & 0xffffffff;
+ bh = (regs->regs[18]) >> 32;
+ bl = (regs->regs[18]) & 0xffffffff;
+ ch = (regs->regs[15]) >> 32;
+ cl = (regs->regs[15]) & 0xffffffff;
+ printk("PC : %08Lx%08Lx LINK: %08Lx%08Lx SP : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->sr) >> 32;
+ al = (regs->sr) & 0xffffffff;
+ asm volatile ("getcon " __TEA ", %0" : "=r" (bh));
+ asm volatile ("getcon " __TEA ", %0" : "=r" (bl));
+ bh = (bh) >> 32;
+ bl = (bl) & 0xffffffff;
+ asm volatile ("getcon " __KCR0 ", %0" : "=r" (ch));
+ asm volatile ("getcon " __KCR0 ", %0" : "=r" (cl));
+ ch = (ch) >> 32;
+ cl = (cl) & 0xffffffff;
+ printk("SR : %08Lx%08Lx TEA : %08Lx%08Lx KCR0: %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[0]) >> 32;
+ al = (regs->regs[0]) & 0xffffffff;
+ bh = (regs->regs[1]) >> 32;
+ bl = (regs->regs[1]) & 0xffffffff;
+ ch = (regs->regs[2]) >> 32;
+ cl = (regs->regs[2]) & 0xffffffff;
+ printk("R0 : %08Lx%08Lx R1 : %08Lx%08Lx R2 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[3]) >> 32;
+ al = (regs->regs[3]) & 0xffffffff;
+ bh = (regs->regs[4]) >> 32;
+ bl = (regs->regs[4]) & 0xffffffff;
+ ch = (regs->regs[5]) >> 32;
+ cl = (regs->regs[5]) & 0xffffffff;
+ printk("R3 : %08Lx%08Lx R4 : %08Lx%08Lx R5 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[6]) >> 32;
+ al = (regs->regs[6]) & 0xffffffff;
+ bh = (regs->regs[7]) >> 32;
+ bl = (regs->regs[7]) & 0xffffffff;
+ ch = (regs->regs[8]) >> 32;
+ cl = (regs->regs[8]) & 0xffffffff;
+ printk("R6 : %08Lx%08Lx R7 : %08Lx%08Lx R8 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[9]) >> 32;
+ al = (regs->regs[9]) & 0xffffffff;
+ bh = (regs->regs[10]) >> 32;
+ bl = (regs->regs[10]) & 0xffffffff;
+ ch = (regs->regs[11]) >> 32;
+ cl = (regs->regs[11]) & 0xffffffff;
+ printk("R9 : %08Lx%08Lx R10 : %08Lx%08Lx R11 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[12]) >> 32;
+ al = (regs->regs[12]) & 0xffffffff;
+ bh = (regs->regs[13]) >> 32;
+ bl = (regs->regs[13]) & 0xffffffff;
+ ch = (regs->regs[14]) >> 32;
+ cl = (regs->regs[14]) & 0xffffffff;
+ printk("R12 : %08Lx%08Lx R13 : %08Lx%08Lx R14 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[16]) >> 32;
+ al = (regs->regs[16]) & 0xffffffff;
+ bh = (regs->regs[17]) >> 32;
+ bl = (regs->regs[17]) & 0xffffffff;
+ ch = (regs->regs[19]) >> 32;
+ cl = (regs->regs[19]) & 0xffffffff;
+ printk("R16 : %08Lx%08Lx R17 : %08Lx%08Lx R19 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[20]) >> 32;
+ al = (regs->regs[20]) & 0xffffffff;
+ bh = (regs->regs[21]) >> 32;
+ bl = (regs->regs[21]) & 0xffffffff;
+ ch = (regs->regs[22]) >> 32;
+ cl = (regs->regs[22]) & 0xffffffff;
+ printk("R20 : %08Lx%08Lx R21 : %08Lx%08Lx R22 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[23]) >> 32;
+ al = (regs->regs[23]) & 0xffffffff;
+ bh = (regs->regs[24]) >> 32;
+ bl = (regs->regs[24]) & 0xffffffff;
+ ch = (regs->regs[25]) >> 32;
+ cl = (regs->regs[25]) & 0xffffffff;
+ printk("R23 : %08Lx%08Lx R24 : %08Lx%08Lx R25 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[26]) >> 32;
+ al = (regs->regs[26]) & 0xffffffff;
+ bh = (regs->regs[27]) >> 32;
+ bl = (regs->regs[27]) & 0xffffffff;
+ ch = (regs->regs[28]) >> 32;
+ cl = (regs->regs[28]) & 0xffffffff;
+ printk("R26 : %08Lx%08Lx R27 : %08Lx%08Lx R28 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[29]) >> 32;
+ al = (regs->regs[29]) & 0xffffffff;
+ bh = (regs->regs[30]) >> 32;
+ bl = (regs->regs[30]) & 0xffffffff;
+ ch = (regs->regs[31]) >> 32;
+ cl = (regs->regs[31]) & 0xffffffff;
+ printk("R29 : %08Lx%08Lx R30 : %08Lx%08Lx R31 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[32]) >> 32;
+ al = (regs->regs[32]) & 0xffffffff;
+ bh = (regs->regs[33]) >> 32;
+ bl = (regs->regs[33]) & 0xffffffff;
+ ch = (regs->regs[34]) >> 32;
+ cl = (regs->regs[34]) & 0xffffffff;
+ printk("R32 : %08Lx%08Lx R33 : %08Lx%08Lx R34 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[35]) >> 32;
+ al = (regs->regs[35]) & 0xffffffff;
+ bh = (regs->regs[36]) >> 32;
+ bl = (regs->regs[36]) & 0xffffffff;
+ ch = (regs->regs[37]) >> 32;
+ cl = (regs->regs[37]) & 0xffffffff;
+ printk("R35 : %08Lx%08Lx R36 : %08Lx%08Lx R37 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[38]) >> 32;
+ al = (regs->regs[38]) & 0xffffffff;
+ bh = (regs->regs[39]) >> 32;
+ bl = (regs->regs[39]) & 0xffffffff;
+ ch = (regs->regs[40]) >> 32;
+ cl = (regs->regs[40]) & 0xffffffff;
+ printk("R38 : %08Lx%08Lx R39 : %08Lx%08Lx R40 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[41]) >> 32;
+ al = (regs->regs[41]) & 0xffffffff;
+ bh = (regs->regs[42]) >> 32;
+ bl = (regs->regs[42]) & 0xffffffff;
+ ch = (regs->regs[43]) >> 32;
+ cl = (regs->regs[43]) & 0xffffffff;
+ printk("R41 : %08Lx%08Lx R42 : %08Lx%08Lx R43 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[44]) >> 32;
+ al = (regs->regs[44]) & 0xffffffff;
+ bh = (regs->regs[45]) >> 32;
+ bl = (regs->regs[45]) & 0xffffffff;
+ ch = (regs->regs[46]) >> 32;
+ cl = (regs->regs[46]) & 0xffffffff;
+ printk("R44 : %08Lx%08Lx R45 : %08Lx%08Lx R46 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[47]) >> 32;
+ al = (regs->regs[47]) & 0xffffffff;
+ bh = (regs->regs[48]) >> 32;
+ bl = (regs->regs[48]) & 0xffffffff;
+ ch = (regs->regs[49]) >> 32;
+ cl = (regs->regs[49]) & 0xffffffff;
+ printk("R47 : %08Lx%08Lx R48 : %08Lx%08Lx R49 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[50]) >> 32;
+ al = (regs->regs[50]) & 0xffffffff;
+ bh = (regs->regs[51]) >> 32;
+ bl = (regs->regs[51]) & 0xffffffff;
+ ch = (regs->regs[52]) >> 32;
+ cl = (regs->regs[52]) & 0xffffffff;
+ printk("R50 : %08Lx%08Lx R51 : %08Lx%08Lx R52 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[53]) >> 32;
+ al = (regs->regs[53]) & 0xffffffff;
+ bh = (regs->regs[54]) >> 32;
+ bl = (regs->regs[54]) & 0xffffffff;
+ ch = (regs->regs[55]) >> 32;
+ cl = (regs->regs[55]) & 0xffffffff;
+ printk("R53 : %08Lx%08Lx R54 : %08Lx%08Lx R55 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[56]) >> 32;
+ al = (regs->regs[56]) & 0xffffffff;
+ bh = (regs->regs[57]) >> 32;
+ bl = (regs->regs[57]) & 0xffffffff;
+ ch = (regs->regs[58]) >> 32;
+ cl = (regs->regs[58]) & 0xffffffff;
+ printk("R56 : %08Lx%08Lx R57 : %08Lx%08Lx R58 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[59]) >> 32;
+ al = (regs->regs[59]) & 0xffffffff;
+ bh = (regs->regs[60]) >> 32;
+ bl = (regs->regs[60]) & 0xffffffff;
+ ch = (regs->regs[61]) >> 32;
+ cl = (regs->regs[61]) & 0xffffffff;
+ printk("R59 : %08Lx%08Lx R60 : %08Lx%08Lx R61 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->regs[62]) >> 32;
+ al = (regs->regs[62]) & 0xffffffff;
+ bh = (regs->tregs[0]) >> 32;
+ bl = (regs->tregs[0]) & 0xffffffff;
+ ch = (regs->tregs[1]) >> 32;
+ cl = (regs->tregs[1]) & 0xffffffff;
+ printk("R62 : %08Lx%08Lx T0 : %08Lx%08Lx T1 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->tregs[2]) >> 32;
+ al = (regs->tregs[2]) & 0xffffffff;
+ bh = (regs->tregs[3]) >> 32;
+ bl = (regs->tregs[3]) & 0xffffffff;
+ ch = (regs->tregs[4]) >> 32;
+ cl = (regs->tregs[4]) & 0xffffffff;
+ printk("T2 : %08Lx%08Lx T3 : %08Lx%08Lx T4 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ ah = (regs->tregs[5]) >> 32;
+ al = (regs->tregs[5]) & 0xffffffff;
+ bh = (regs->tregs[6]) >> 32;
+ bl = (regs->tregs[6]) & 0xffffffff;
+ ch = (regs->tregs[7]) >> 32;
+ cl = (regs->tregs[7]) & 0xffffffff;
+ printk("T5 : %08Lx%08Lx T6 : %08Lx%08Lx T7 : %08Lx%08Lx\n",
+ ah, al, bh, bl, ch, cl);
+
+ /*
+ * If we're in kernel mode, dump the stack too..
+ */
+ if (!user_mode(regs)) {
+ void show_stack(struct task_struct *tsk, unsigned long *sp);
+ unsigned long sp = regs->regs[15] & 0xffffffff;
+ struct task_struct *tsk = get_current();
+
+ tsk->thread.kregs = regs;
+
+ show_stack(tsk, (unsigned long *)sp);
+ }
+}
+
+struct task_struct * alloc_task_struct(void)
+{
+ /* Get task descriptor pages */
+ return (struct task_struct *)
+ __get_free_pages(GFP_KERNEL, get_order(THREAD_SIZE));
+}
+
+void free_task_struct(struct task_struct *p)
+{
+ free_pages((unsigned long) p, get_order(THREAD_SIZE));
+}
+
+/*
+ * Create a kernel thread
+ */
+
+/*
+ * This is the mechanism for creating a new kernel thread.
+ *
+ * NOTE! Only a kernel-only process(ie the swapper or direct descendants
+ * who haven't done an "execve()") should use this: it will work within
+ * a system call from a "real" process, but the process memory space will
+ * not be free'd until both the parent and the child have exited.
+ */
+int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
+{
+ /* A bit less processor dependent than older sh ... */
+ unsigned int reply;
+
+static __inline__ _syscall2(int,clone,unsigned long,flags,unsigned long,newsp)
+static __inline__ _syscall1(int,exit,int,ret)
+
+ reply = clone(flags | CLONE_VM, 0);
+ if (!reply) {
+ /* Child */
+ reply = exit(fn(arg));
+ }
+
+ return reply;
+}
+
+/*
+ * Free current thread data structures etc..
+ */
+void exit_thread(void)
+{
+ /* See arch/sparc/kernel/process.c for the precedent for doing this -- RPC.
+
+ The SH-5 FPU save/restore approach relies on last_task_used_math
+ pointing to a live task_struct. When another task tries to use the
+ FPU for the 1st time, the FPUDIS trap handling (see
+ arch/sh64/kernel/fpu.c) will save the existing FPU state to the
+ FP regs field within last_task_used_math before re-loading the new
+ task's FPU state (or initialising it if the FPU has been used
+ before). So if last_task_used_math is stale, and its page has already been
+ re-allocated for another use, the consequences are rather grim. Unless we
+ null it here, there is no other path through which it would get safely
+ nulled. */
+
+#ifdef CONFIG_SH_FPU
+ if (last_task_used_math == current) {
+ last_task_used_math = NULL;
+ }
+#endif
+}
+
+void flush_thread(void)
+{
+
+ /* Called by fs/exec.c (flush_old_exec) to remove traces of a
+ * previously running executable. */
+#ifdef CONFIG_SH_FPU
+ if (last_task_used_math == current) {
+ last_task_used_math = NULL;
+ }
+ /* Force FPU state to be reinitialised after exec */
+ clear_used_math();
+#endif
+
+ /* if we are a kernel thread, about to change to user thread,
+ * update kreg
+ */
+ if(current->thread.kregs==&fake_swapper_regs) {
+ current->thread.kregs =
+ ((struct pt_regs *)(THREAD_SIZE + (unsigned long) current) - 1);
+ current->thread.uregs = current->thread.kregs;
+ }
+}
+
+void release_thread(struct task_struct *dead_task)
+{
+ /* do nothing */
+}
+
+/* Fill in the fpu structure for a core dump.. */
+int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
+{
+#ifdef CONFIG_SH_FPU
+ int fpvalid;
+ struct task_struct *tsk = current;
+
+ fpvalid = !!tsk_used_math(tsk);
+ if (fpvalid) {
+ if (current == last_task_used_math) {
+ grab_fpu();
+ fpsave(&tsk->thread.fpu.hard);
+ release_fpu();
+ last_task_used_math = 0;
+ regs->sr |= SR_FD;
+ }
+
+ memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu));
+ }
+
+ return fpvalid;
+#else
+ return 0; /* Task didn't use the fpu at all. */
+#endif
+}
+
+asmlinkage void ret_from_fork(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 pt_regs *childregs;
+ unsigned long long se; /* Sign extension */
+
+#ifdef CONFIG_SH_FPU
+ if(last_task_used_math == current) {
+ grab_fpu();
+ fpsave(&current->thread.fpu.hard);
+ release_fpu();
+ last_task_used_math = NULL;
+ regs->sr |= SR_FD;
+ }
+#endif
+ /* Copy from sh version */
+ childregs = ((struct pt_regs *)(THREAD_SIZE + (unsigned long) p->thread_info )) - 1;
+
+ *childregs = *regs;
+
+ if (user_mode(regs)) {
+ childregs->regs[15] = usp;
+ p->thread.uregs = childregs;
+ } else {
+ childregs->regs[15] = (unsigned long)p->thread_info + THREAD_SIZE;
+ }
+
+ childregs->regs[9] = 0; /* Set return value for child */
+ childregs->sr |= SR_FD; /* Invalidate FPU flag */
+
+ p->thread.sp = (unsigned long) childregs;
+ p->thread.pc = (unsigned long) ret_from_fork;
+
+ /*
+ * Sign extend the edited stack.
+ * Note that thread.pc and thread.pc will stay
+ * 32-bit wide and context switch must take care
+ * of NEFF sign extension.
+ */
+
+ se = childregs->regs[15];
+ se = (se & NEFF_SIGN) ? (se | NEFF_MASK) : se;
+ childregs->regs[15] = se;
+
+ return 0;
+}
+
+/*
+ * fill in the user structure for a core dump..
+ */
+void dump_thread(struct pt_regs * regs, struct user * dump)
+{
+ dump->magic = CMAGIC;
+ dump->start_code = current->mm->start_code;
+ dump->start_data = current->mm->start_data;
+ dump->start_stack = regs->regs[15] & ~(PAGE_SIZE - 1);
+ dump->u_tsize = (current->mm->end_code - dump->start_code) >> PAGE_SHIFT;
+ dump->u_dsize = (current->mm->brk + (PAGE_SIZE-1) - dump->start_data) >> PAGE_SHIFT;
+ dump->u_ssize = (current->mm->start_stack - dump->start_stack +
+ PAGE_SIZE - 1) >> PAGE_SHIFT;
+ /* Debug registers will come here. */
+
+ dump->regs = *regs;
+
+ dump->u_fpvalid = dump_fpu(regs, &dump->fpu);
+}
+
+asmlinkage int sys_fork(unsigned long r2, unsigned long r3,
+ unsigned long r4, unsigned long r5,
+ unsigned long r6, unsigned long r7,
+ struct pt_regs *pregs)
+{
+ return do_fork(SIGCHLD, pregs->regs[15], pregs, 0, 0, 0);
+}
+
+asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
+ unsigned long r4, unsigned long r5,
+ unsigned long r6, unsigned long r7,
+ struct pt_regs *pregs)
+{
+ if (!newsp)
+ newsp = pregs->regs[15];
+ return do_fork(clone_flags, newsp, pregs, 0, 0, 0);
+}
+
+/*
+ * This is trivial, and on the face of it looks like it
+ * could equally well be done in user mode.
+ *
+ * Not so, for quite unobvious reasons - register pressure.
+ * In user mode vfork() cannot have a stack frame, and if
+ * done by calling the "clone()" system call directly, you
+ * do not have enough call-clobbered registers to hold all
+ * the information you need.
+ */
+asmlinkage int sys_vfork(unsigned long r2, unsigned long r3,
+ unsigned long r4, unsigned long r5,
+ unsigned long r6, unsigned long r7,
+ struct pt_regs *pregs)
+{
+ return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, pregs->regs[15], pregs, 0, 0, 0);
+}
+
+/*
+ * sys_execve() executes a new program.
+ */
+asmlinkage int sys_execve(char *ufilename, char **uargv,
+ char **uenvp, unsigned long r5,
+ unsigned long r6, unsigned long r7,
+ struct pt_regs *pregs)
+{
+ int error;
+ char *filename;
+
+ lock_kernel();
+ filename = getname((char __user *)ufilename);
+ error = PTR_ERR(filename);
+ if (IS_ERR(filename))
+ goto out;
+
+ error = do_execve(filename,
+ (char __user * __user *)uargv,
+ (char __user * __user *)uenvp,
+ pregs);
+ if (error == 0) {
+ task_lock(current);
+ current->ptrace &= ~PT_DTRACE;
+ task_unlock(current);
+ }
+ putname(filename);
+out:
+ unlock_kernel();
+ return error;
+}
+
+/*
+ * These bracket the sleeping functions..
+ */
+extern void interruptible_sleep_on(wait_queue_head_t *q);
+
+#define mid_sched ((unsigned long) interruptible_sleep_on)
+
+static int in_sh64_switch_to(unsigned long pc)
+{
+ extern char __sh64_switch_to_end;
+ /* For a sleeping task, the PC is somewhere in the middle of the function,
+ so we don't have to worry about masking the LSB off */
+ return (pc >= (unsigned long) sh64_switch_to) &&
+ (pc < (unsigned long) &__sh64_switch_to_end);
+}
+
+unsigned long get_wchan(struct task_struct *p)
+{
+ unsigned long schedule_fp;
+ unsigned long sh64_switch_to_fp;
+ unsigned long schedule_caller_pc;
+ unsigned long pc;
+
+ if (!p || p == current || p->state == TASK_RUNNING)
+ return 0;
+
+ /*
+ * The same comment as on the Alpha applies here, too ...
+ */
+ pc = thread_saved_pc(p);
+
+#ifdef CONFIG_FRAME_POINTER
+ if (in_sh64_switch_to(pc)) {
+ sh64_switch_to_fp = (long) p->thread.sp;
+ /* r14 is saved at offset 4 in the sh64_switch_to frame */
+ schedule_fp = *(unsigned long *) (long)(sh64_switch_to_fp + 4);
+
+ /* and the caller of 'schedule' is (currently!) saved at offset 24
+ in the frame of schedule (from disasm) */
+ schedule_caller_pc = *(unsigned long *) (long)(schedule_fp + 24);
+ return schedule_caller_pc;
+ }
+#endif
+ return pc;
+}
+
+/* Provide a /proc/asids file that lists out the
+ ASIDs currently associated with the processes. (If the DM.PC register is
+ examined through the debug link, this shows ASID + PC. To make use of this,
+ the PID->ASID relationship needs to be known. This is primarily for
+ debugging.)
+ */
+
+#if defined(CONFIG_SH64_PROC_ASIDS)
+#include <linux/init.h>
+#include <linux/proc_fs.h>
+
+static int
+asids_proc_info(char *buf, char **start, off_t fpos, int length, int *eof, void *data)
+{
+ int len=0;
+ struct task_struct *p;
+ read_lock(&tasklist_lock);
+ for_each_process(p) {
+ int pid = p->pid;
+ struct mm_struct *mm;
+ if (!pid) continue;
+ mm = p->mm;
+ if (mm) {
+ unsigned long asid, context;
+ context = mm->context;
+ asid = (context & 0xff);
+ len += sprintf(buf+len, "%5d : %02lx\n", pid, asid);
+ } else {
+ len += sprintf(buf+len, "%5d : (none)\n", pid);
+ }
+ }
+ read_unlock(&tasklist_lock);
+ *eof = 1;
+ return len;
+}
+
+static int __init register_proc_asids(void)
+{
+ create_proc_read_entry("asids", 0, NULL, asids_proc_info, NULL);
+ return 0;
+}
+
+__initcall(register_proc_asids);
+#endif
+