Linux-2.6.12-rc2v2.6.12-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, 423 insertions, 0 deletions

diff --git a/arch/parisc/kernel/ptrace.c b/arch/parisc/kernel/ptrace.c
new file mode 100644
index 00000000000..2937a923638
--- /dev/null
+++ b/arch/parisc/kernel/ptrace.c
@@ -0,0 +1,423 @@
+/*
+ * Kernel support for the ptrace() and syscall tracing interfaces.
+ *
+ * Copyright (C) 2000 Hewlett-Packard Co, Linuxcare Inc.
+ * Copyright (C) 2000 Matthew Wilcox <matthew@wil.cx>
+ * Copyright (C) 2000 David Huggins-Daines <dhd@debian.org>
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/personality.h>
+#include <linux/security.h>
+#include <linux/compat.h>
+
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/system.h>
+#include <asm/processor.h>
+#include <asm/offsets.h>
+
+/* PSW bits we allow the debugger to modify */
+#define USER_PSW_BITS	(PSW_N | PSW_V | PSW_CB)
+
+#undef DEBUG_PTRACE
+
+#ifdef DEBUG_PTRACE
+#define DBG(x...)	printk(x)
+#else
+#define DBG(x...)
+#endif
+
+#ifdef __LP64__
+
+/* This function is needed to translate 32 bit pt_regs offsets in to
+ * 64 bit pt_regs offsets.  For example, a 32 bit gdb under a 64 bit kernel
+ * will request offset 12 if it wants gr3, but the lower 32 bits of
+ * the 64 bit kernels view of gr3 will be at offset 28 (3*8 + 4).
+ * This code relies on a 32 bit pt_regs being comprised of 32 bit values
+ * except for the fp registers which (a) are 64 bits, and (b) follow
+ * the gr registers at the start of pt_regs.  The 32 bit pt_regs should
+ * be half the size of the 64 bit pt_regs, plus 32*4 to allow for fr[]
+ * being 64 bit in both cases.
+ */
+
+static long translate_usr_offset(long offset)
+{
+	if (offset < 0)
+		return -1;
+	else if (offset <= 32*4)	/* gr[0..31] */
+		return offset * 2 + 4;
+	else if (offset <= 32*4+32*8)	/* gr[0..31] + fr[0..31] */
+		return offset + 32*4;
+	else if (offset < sizeof(struct pt_regs)/2 + 32*4)
+		return offset * 2 + 4 - 32*8;
+	else
+		return -1;
+}
+#endif
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ *
+ * Make sure single step bits etc are not set.
+ */
+void ptrace_disable(struct task_struct *child)
+{
+	/* make sure the trap bits are not set */
+	pa_psw(child)->r = 0;
+	pa_psw(child)->t = 0;
+	pa_psw(child)->h = 0;
+	pa_psw(child)->l = 0;
+}
+
+long sys_ptrace(long request, pid_t pid, long addr, long data)
+{
+	struct task_struct *child;
+	long ret;
+#ifdef DEBUG_PTRACE
+	long oaddr=addr, odata=data;
+#endif
+
+	lock_kernel();
+	ret = -EPERM;
+	if (request == PTRACE_TRACEME) {
+		/* are we already being traced? */
+		if (current->ptrace & PT_PTRACED)
+			goto out;
+
+		ret = security_ptrace(current->parent, current);
+		if (ret) 
+			goto out;
+
+		/* set the ptrace bit in the process flags. */
+		current->ptrace |= PT_PTRACED;
+		ret = 0;
+		goto out;
+	}
+
+	ret = -ESRCH;
+	read_lock(&tasklist_lock);
+	child = find_task_by_pid(pid);
+	if (child)
+		get_task_struct(child);
+	read_unlock(&tasklist_lock);
+	if (!child)
+		goto out;
+	ret = -EPERM;
+	if (pid == 1)		/* no messing around with init! */
+		goto out_tsk;
+
+	if (request == PTRACE_ATTACH) {
+		ret = ptrace_attach(child);
+		goto out_tsk;
+	}
+
+	ret = ptrace_check_attach(child, request == PTRACE_KILL);
+	if (ret < 0)
+		goto out_tsk;
+
+	switch (request) {
+	case PTRACE_PEEKTEXT: /* read word at location addr. */ 
+	case PTRACE_PEEKDATA: {
+		int copied;
+
+#ifdef __LP64__
+		if (is_compat_task(child)) {
+			unsigned int tmp;
+
+			addr &= 0xffffffffL;
+			copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
+			ret = -EIO;
+			if (copied != sizeof(tmp))
+				goto out_tsk;
+			ret = put_user(tmp,(unsigned int *) data);
+			DBG("sys_ptrace(PEEK%s, %d, %lx, %lx) returning %ld, data %x\n",
+				request == PTRACE_PEEKTEXT ? "TEXT" : "DATA",
+				pid, oaddr, odata, ret, tmp);
+		}
+		else
+#endif
+		{
+			unsigned long tmp;
+
+			copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
+			ret = -EIO;
+			if (copied != sizeof(tmp))
+				goto out_tsk;
+			ret = put_user(tmp,(unsigned long *) data);
+		}
+		goto out_tsk;
+	}
+
+	/* when I and D space are separate, this will have to be fixed. */
+	case PTRACE_POKETEXT: /* write the word at location addr. */
+	case PTRACE_POKEDATA:
+		ret = 0;
+#ifdef __LP64__
+		if (is_compat_task(child)) {
+			unsigned int tmp = (unsigned int)data;
+			DBG("sys_ptrace(POKE%s, %d, %lx, %lx)\n",
+				request == PTRACE_POKETEXT ? "TEXT" : "DATA",
+				pid, oaddr, odata);
+			addr &= 0xffffffffL;
+			if (access_process_vm(child, addr, &tmp, sizeof(tmp), 1) == sizeof(tmp))
+				goto out_tsk;
+		}
+		else
+#endif
+		{
+			if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data))
+				goto out_tsk;
+		}
+		ret = -EIO;
+		goto out_tsk;
+
+	/* Read the word at location addr in the USER area.  For ptraced
+	   processes, the kernel saves all regs on a syscall. */
+	case PTRACE_PEEKUSR: {
+		ret = -EIO;
+#ifdef __LP64__
+		if (is_compat_task(child)) {
+			unsigned int tmp;
+
+			if (addr & (sizeof(int)-1))
+				goto out_tsk;
+			if ((addr = translate_usr_offset(addr)) < 0)
+				goto out_tsk;
+
+			tmp = *(unsigned int *) ((char *) task_regs(child) + addr);
+			ret = put_user(tmp, (unsigned int *) data);
+			DBG("sys_ptrace(PEEKUSR, %d, %lx, %lx) returning %ld, addr %lx, data %x\n",
+				pid, oaddr, odata, ret, addr, tmp);
+		}
+		else
+#endif
+		{
+			unsigned long tmp;
+
+			if ((addr & (sizeof(long)-1)) || (unsigned long) addr >= sizeof(struct pt_regs))
+				goto out_tsk;
+			tmp = *(unsigned long *) ((char *) task_regs(child) + addr);
+			ret = put_user(tmp, (unsigned long *) data);
+		}
+		goto out_tsk;
+	}
+
+	/* Write the word at location addr in the USER area.  This will need
+	   to change when the kernel no longer saves all regs on a syscall.
+	   FIXME.  There is a problem at the moment in that r3-r18 are only
+	   saved if the process is ptraced on syscall entry, and even then
+	   those values are overwritten by actual register values on syscall
+	   exit. */
+	case PTRACE_POKEUSR:
+		ret = -EIO;
+		/* Some register values written here may be ignored in
+		 * entry.S:syscall_restore_rfi; e.g. iaoq is written with
+		 * r31/r31+4, and not with the values in pt_regs.
+		 */
+		 /* PT_PSW=0, so this is valid for 32 bit processes under 64
+		 * bit kernels.
+		 */
+		if (addr == PT_PSW) {
+			/* PT_PSW=0, so this is valid for 32 bit processes
+			 * under 64 bit kernels.
+			 *
+			 * Allow writing to Nullify, Divide-step-correction,
+			 * and carry/borrow bits.
+			 * BEWARE, if you set N, and then single step, it won't
+			 * stop on the nullified instruction.
+			 */
+			DBG("sys_ptrace(POKEUSR, %d, %lx, %lx)\n",
+				pid, oaddr, odata);
+			data &= USER_PSW_BITS;
+			task_regs(child)->gr[0] &= ~USER_PSW_BITS;
+			task_regs(child)->gr[0] |= data;
+			ret = 0;
+			goto out_tsk;
+		}
+#ifdef __LP64__
+		if (is_compat_task(child)) {
+			if (addr & (sizeof(int)-1))
+				goto out_tsk;
+			if ((addr = translate_usr_offset(addr)) < 0)
+				goto out_tsk;
+			DBG("sys_ptrace(POKEUSR, %d, %lx, %lx) addr %lx\n",
+				pid, oaddr, odata, addr);
+			if (addr >= PT_FR0 && addr <= PT_FR31 + 4) {
+				/* Special case, fp regs are 64 bits anyway */
+				*(unsigned int *) ((char *) task_regs(child) + addr) = data;
+				ret = 0;
+			}
+			else if ((addr >= PT_GR1+4 && addr <= PT_GR31+4) ||
+					addr == PT_IAOQ0+4 || addr == PT_IAOQ1+4 ||
+					addr == PT_SAR+4) {
+				/* Zero the top 32 bits */
+				*(unsigned int *) ((char *) task_regs(child) + addr - 4) = 0;
+				*(unsigned int *) ((char *) task_regs(child) + addr) = data;
+				ret = 0;
+			}
+			goto out_tsk;
+		}
+		else
+#endif
+		{
+			if ((addr & (sizeof(long)-1)) || (unsigned long) addr >= sizeof(struct pt_regs))
+				goto out_tsk;
+			if ((addr >= PT_GR1 && addr <= PT_GR31) ||
+					addr == PT_IAOQ0 || addr == PT_IAOQ1 ||
+					(addr >= PT_FR0 && addr <= PT_FR31 + 4) ||
+					addr == PT_SAR) {
+				*(unsigned long *) ((char *) task_regs(child) + addr) = data;
+				ret = 0;
+			}
+			goto out_tsk;
+		}
+
+	case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
+	case PTRACE_CONT:
+		ret = -EIO;
+		DBG("sys_ptrace(%s)\n",
+			request == PTRACE_SYSCALL ? "SYSCALL" : "CONT");
+		if ((unsigned long) data > _NSIG)
+			goto out_tsk;
+		child->ptrace &= ~(PT_SINGLESTEP|PT_BLOCKSTEP);
+		if (request == PTRACE_SYSCALL) {
+			set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+		} else {
+			clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+		}		
+		child->exit_code = data;
+		goto out_wake_notrap;
+
+	case PTRACE_KILL:
+		/*
+		 * make the child exit.  Best I can do is send it a
+		 * sigkill.  perhaps it should be put in the status
+		 * that it wants to exit.
+		 */
+		DBG("sys_ptrace(KILL)\n");
+		if (child->exit_state == EXIT_ZOMBIE)	/* already dead */
+			goto out_tsk;
+		child->exit_code = SIGKILL;
+		goto out_wake_notrap;
+
+	case PTRACE_SINGLEBLOCK:
+		DBG("sys_ptrace(SINGLEBLOCK)\n");
+		ret = -EIO;
+		if ((unsigned long) data > _NSIG)
+			goto out_tsk;
+		clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+		child->ptrace &= ~PT_SINGLESTEP;
+		child->ptrace |= PT_BLOCKSTEP;
+		child->exit_code = data;
+
+		/* Enable taken branch trap. */
+		pa_psw(child)->r = 0;
+		pa_psw(child)->t = 1;
+		pa_psw(child)->h = 0;
+		pa_psw(child)->l = 0;
+		goto out_wake;
+
+	case PTRACE_SINGLESTEP:
+		DBG("sys_ptrace(SINGLESTEP)\n");
+		ret = -EIO;
+		if ((unsigned long) data > _NSIG)
+			goto out_tsk;
+
+		clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+		child->ptrace &= ~PT_BLOCKSTEP;
+		child->ptrace |= PT_SINGLESTEP;
+		child->exit_code = data;
+
+		if (pa_psw(child)->n) {
+			struct siginfo si;
+
+			/* Nullified, just crank over the queue. */
+			task_regs(child)->iaoq[0] = task_regs(child)->iaoq[1];
+			task_regs(child)->iasq[0] = task_regs(child)->iasq[1];
+			task_regs(child)->iaoq[1] = task_regs(child)->iaoq[0] + 4;
+			pa_psw(child)->n = 0;
+			pa_psw(child)->x = 0;
+			pa_psw(child)->y = 0;
+			pa_psw(child)->z = 0;
+			pa_psw(child)->b = 0;
+			ptrace_disable(child);
+			/* Don't wake up the child, but let the
+			   parent know something happened. */
+			si.si_code = TRAP_TRACE;
+			si.si_addr = (void __user *) (task_regs(child)->iaoq[0] & ~3);
+			si.si_signo = SIGTRAP;
+			si.si_errno = 0;
+			force_sig_info(SIGTRAP, &si, child);
+			//notify_parent(child, SIGCHLD);
+			//ret = 0;
+			goto out_wake;
+		}
+
+		/* Enable recovery counter traps.  The recovery counter
+		 * itself will be set to zero on a task switch.  If the
+		 * task is suspended on a syscall then the syscall return
+		 * path will overwrite the recovery counter with a suitable
+		 * value such that it traps once back in user space.  We
+		 * disable interrupts in the childs PSW here also, to avoid
+		 * interrupts while the recovery counter is decrementing.
+		 */
+		pa_psw(child)->r = 1;
+		pa_psw(child)->t = 0;
+		pa_psw(child)->h = 0;
+		pa_psw(child)->l = 0;
+		/* give it a chance to run. */
+		goto out_wake;
+
+	case PTRACE_DETACH:
+		ret = ptrace_detach(child, data);
+		goto out_tsk;
+
+	case PTRACE_GETEVENTMSG:
+                ret = put_user(child->ptrace_message, (unsigned int __user *) data);
+		goto out_tsk;
+
+	default:
+		ret = ptrace_request(child, request, addr, data);
+		goto out_tsk;
+	}
+
+out_wake_notrap:
+	ptrace_disable(child);
+out_wake:
+	wake_up_process(child);
+	ret = 0;
+out_tsk:
+	put_task_struct(child);
+out:
+	unlock_kernel();
+	DBG("sys_ptrace(%ld, %d, %lx, %lx) returning %ld\n",
+		request, pid, oaddr, odata, ret);
+	return ret;
+}
+
+void syscall_trace(void)
+{
+	if (!test_thread_flag(TIF_SYSCALL_TRACE))
+		return;
+	if (!(current->ptrace & PT_PTRACED))
+		return;
+	ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
+				 ? 0x80 : 0));
+	/*
+	 * this isn't the same as continuing with a signal, but it will do
+	 * for normal use.  strace only continues with a signal if the
+	 * stopping signal is not SIGTRAP.  -brl
+	 */
+	if (current->exit_code) {
+		send_sig(current->exit_code, current, 1);
+		current->exit_code = 0;
+	}
+}