Initial import

1 files changed, 354 insertions, 0 deletions

diff --git a/arch/xtensa/kernel/ptrace.c b/arch/xtensa/kernel/ptrace.c
new file mode 100644
index 000000000..4d54b4811
--- /dev/null
+++ b/arch/xtensa/kernel/ptrace.c
@@ -0,0 +1,354 @@
+// TODO some minor issues
+/*
+ * 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) 2001 - 2007  Tensilica Inc.
+ *
+ * Joe Taylor	<joe@tensilica.com, joetylr@yahoo.com>
+ * Chris Zankel <chris@zankel.net>
+ * Scott Foehner<sfoehner@yahoo.com>,
+ * Kevin Chea
+ * Marc Gauthier<marc@tensilica.com> <marc@alumni.uwaterloo.ca>
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/smp.h>
+#include <linux/security.h>
+#include <linux/signal.h>
+
+#include <asm/pgtable.h>
+#include <asm/page.h>
+#include <asm/uaccess.h>
+#include <asm/ptrace.h>
+#include <asm/elf.h>
+#include <asm/coprocessor.h>
+
+
+void user_enable_single_step(struct task_struct *child)
+{
+	child->ptrace |= PT_SINGLESTEP;
+}
+
+void user_disable_single_step(struct task_struct *child)
+{
+	child->ptrace &= ~PT_SINGLESTEP;
+}
+
+/*
+ * Called by kernel/ptrace.c when detaching to disable single stepping.
+ */
+
+void ptrace_disable(struct task_struct *child)
+{
+	/* Nothing to do.. */
+}
+
+int ptrace_getregs(struct task_struct *child, void __user *uregs)
+{
+	struct pt_regs *regs = task_pt_regs(child);
+	xtensa_gregset_t __user *gregset = uregs;
+	unsigned long wb = regs->windowbase;
+	int i;
+
+	if (!access_ok(VERIFY_WRITE, uregs, sizeof(xtensa_gregset_t)))
+		return -EIO;
+
+	__put_user(regs->pc, &gregset->pc);
+	__put_user(regs->ps & ~(1 << PS_EXCM_BIT), &gregset->ps);
+	__put_user(regs->lbeg, &gregset->lbeg);
+	__put_user(regs->lend, &gregset->lend);
+	__put_user(regs->lcount, &gregset->lcount);
+	__put_user(regs->windowstart, &gregset->windowstart);
+	__put_user(regs->windowbase, &gregset->windowbase);
+	__put_user(regs->threadptr, &gregset->threadptr);
+
+	for (i = 0; i < XCHAL_NUM_AREGS; i++)
+		__put_user(regs->areg[i],
+				gregset->a + ((wb * 4 + i) % XCHAL_NUM_AREGS));
+
+	return 0;
+}
+
+int ptrace_setregs(struct task_struct *child, void __user *uregs)
+{
+	struct pt_regs *regs = task_pt_regs(child);
+	xtensa_gregset_t *gregset = uregs;
+	const unsigned long ps_mask = PS_CALLINC_MASK | PS_OWB_MASK;
+	unsigned long ps;
+	unsigned long wb, ws;
+
+	if (!access_ok(VERIFY_WRITE, uregs, sizeof(xtensa_gregset_t)))
+		return -EIO;
+
+	__get_user(regs->pc, &gregset->pc);
+	__get_user(ps, &gregset->ps);
+	__get_user(regs->lbeg, &gregset->lbeg);
+	__get_user(regs->lend, &gregset->lend);
+	__get_user(regs->lcount, &gregset->lcount);
+	__get_user(ws, &gregset->windowstart);
+	__get_user(wb, &gregset->windowbase);
+	__get_user(regs->threadptr, &gregset->threadptr);
+
+	regs->ps = (regs->ps & ~ps_mask) | (ps & ps_mask) | (1 << PS_EXCM_BIT);
+
+	if (wb >= XCHAL_NUM_AREGS / 4)
+		return -EFAULT;
+
+	if (wb != regs->windowbase || ws != regs->windowstart) {
+		unsigned long rotws, wmask;
+
+		rotws = (((ws | (ws << WSBITS)) >> wb) &
+				((1 << WSBITS) - 1)) & ~1;
+		wmask = ((rotws ? WSBITS + 1 - ffs(rotws) : 0) << 4) |
+			(rotws & 0xF) | 1;
+		regs->windowbase = wb;
+		regs->windowstart = ws;
+		regs->wmask = wmask;
+	}
+
+	if (wb != 0 &&  __copy_from_user(regs->areg + XCHAL_NUM_AREGS - wb * 4,
+				gregset->a, wb * 16))
+		return -EFAULT;
+
+	if (__copy_from_user(regs->areg, gregset->a + wb * 4,
+				(WSBITS - wb) * 16))
+		return -EFAULT;
+
+	return 0;
+}
+
+
+int ptrace_getxregs(struct task_struct *child, void __user *uregs)
+{
+	struct pt_regs *regs = task_pt_regs(child);
+	struct thread_info *ti = task_thread_info(child);
+	elf_xtregs_t __user *xtregs = uregs;
+	int ret = 0;
+
+	if (!access_ok(VERIFY_WRITE, uregs, sizeof(elf_xtregs_t)))
+		return -EIO;
+
+#if XTENSA_HAVE_COPROCESSORS
+	/* Flush all coprocessor registers to memory. */
+	coprocessor_flush_all(ti);
+	ret |= __copy_to_user(&xtregs->cp0, &ti->xtregs_cp,
+			      sizeof(xtregs_coprocessor_t));
+#endif
+	ret |= __copy_to_user(&xtregs->opt, &regs->xtregs_opt,
+			      sizeof(xtregs->opt));
+	ret |= __copy_to_user(&xtregs->user,&ti->xtregs_user,
+			      sizeof(xtregs->user));
+
+	return ret ? -EFAULT : 0;
+}
+
+int ptrace_setxregs(struct task_struct *child, void __user *uregs)
+{
+	struct thread_info *ti = task_thread_info(child);
+	struct pt_regs *regs = task_pt_regs(child);
+	elf_xtregs_t *xtregs = uregs;
+	int ret = 0;
+
+	if (!access_ok(VERIFY_READ, uregs, sizeof(elf_xtregs_t)))
+		return -EFAULT;
+
+#if XTENSA_HAVE_COPROCESSORS
+	/* Flush all coprocessors before we overwrite them. */
+	coprocessor_flush_all(ti);
+	coprocessor_release_all(ti);
+
+	ret |= __copy_from_user(&ti->xtregs_cp, &xtregs->cp0,
+				sizeof(xtregs_coprocessor_t));
+#endif
+	ret |= __copy_from_user(&regs->xtregs_opt, &xtregs->opt,
+				sizeof(xtregs->opt));
+	ret |= __copy_from_user(&ti->xtregs_user, &xtregs->user,
+				sizeof(xtregs->user));
+
+	return ret ? -EFAULT : 0;
+}
+
+int ptrace_peekusr(struct task_struct *child, long regno, long __user *ret)
+{
+	struct pt_regs *regs;
+	unsigned long tmp;
+
+	regs = task_pt_regs(child);
+	tmp = 0;  /* Default return value. */
+
+	switch(regno) {
+
+		case REG_AR_BASE ... REG_AR_BASE + XCHAL_NUM_AREGS - 1:
+			tmp = regs->areg[regno - REG_AR_BASE];
+			break;
+
+		case REG_A_BASE ... REG_A_BASE + 15:
+			tmp = regs->areg[regno - REG_A_BASE];
+			break;
+
+		case REG_PC:
+			tmp = regs->pc;
+			break;
+
+		case REG_PS:
+			/* Note:  PS.EXCM is not set while user task is running;
+			 * its being set in regs is for exception handling
+			 * convenience.  */
+			tmp = (regs->ps & ~(1 << PS_EXCM_BIT));
+			break;
+
+		case REG_WB:
+			break;		/* tmp = 0 */
+
+		case REG_WS:
+		{
+			unsigned long wb = regs->windowbase;
+			unsigned long ws = regs->windowstart;
+			tmp = ((ws>>wb) | (ws<<(WSBITS-wb))) & ((1<<WSBITS)-1);
+			break;
+		}
+		case REG_LBEG:
+			tmp = regs->lbeg;
+			break;
+
+		case REG_LEND:
+			tmp = regs->lend;
+			break;
+
+		case REG_LCOUNT:
+			tmp = regs->lcount;
+			break;
+
+		case REG_SAR:
+			tmp = regs->sar;
+			break;
+
+		case SYSCALL_NR:
+			tmp = regs->syscall;
+			break;
+
+		default:
+			return -EIO;
+	}
+	return put_user(tmp, ret);
+}
+
+int ptrace_pokeusr(struct task_struct *child, long regno, long val)
+{
+	struct pt_regs *regs;
+	regs = task_pt_regs(child);
+
+	switch (regno) {
+		case REG_AR_BASE ... REG_AR_BASE + XCHAL_NUM_AREGS - 1:
+			regs->areg[regno - REG_AR_BASE] = val;
+			break;
+
+		case REG_A_BASE ... REG_A_BASE + 15:
+			regs->areg[regno - REG_A_BASE] = val;
+			break;
+
+		case REG_PC:
+			regs->pc = val;
+			break;
+
+		case SYSCALL_NR:
+			regs->syscall = val;
+			break;
+
+		default:
+			return -EIO;
+	}
+	return 0;
+}
+
+long arch_ptrace(struct task_struct *child, long request,
+		 unsigned long addr, unsigned long data)
+{
+	int ret = -EPERM;
+	void __user *datap = (void __user *) data;
+
+	switch (request) {
+	case PTRACE_PEEKTEXT:	/* read word at location addr. */
+	case PTRACE_PEEKDATA:
+		ret = generic_ptrace_peekdata(child, addr, data);
+		break;
+
+	case PTRACE_PEEKUSR:	/* read register specified by addr. */
+		ret = ptrace_peekusr(child, addr, datap);
+		break;
+
+	case PTRACE_POKETEXT:	/* write the word at location addr. */
+	case PTRACE_POKEDATA:
+		ret = generic_ptrace_pokedata(child, addr, data);
+		break;
+
+	case PTRACE_POKEUSR:	/* write register specified by addr. */
+		ret = ptrace_pokeusr(child, addr, data);
+		break;
+
+	case PTRACE_GETREGS:
+		ret = ptrace_getregs(child, datap);
+		break;
+
+	case PTRACE_SETREGS:
+		ret = ptrace_setregs(child, datap);
+		break;
+
+	case PTRACE_GETXTREGS:
+		ret = ptrace_getxregs(child, datap);
+		break;
+
+	case PTRACE_SETXTREGS:
+		ret = ptrace_setxregs(child, datap);
+		break;
+
+	default:
+		ret = ptrace_request(child, request, addr, data);
+		break;
+	}
+
+	return ret;
+}
+
+void do_syscall_trace(void)
+{
+	/*
+	 * The 0x80 provides a way for the tracing parent to distinguish
+	 * between a syscall stop and SIGTRAP delivery
+	 */
+	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;
+	}
+}
+
+void do_syscall_trace_enter(struct pt_regs *regs)
+{
+	if (test_thread_flag(TIF_SYSCALL_TRACE)
+			&& (current->ptrace & PT_PTRACED))
+		do_syscall_trace();
+
+#if 0
+	audit_syscall_entry(...);
+#endif
+}
+
+void do_syscall_trace_leave(struct pt_regs *regs)
+{
+	if ((test_thread_flag(TIF_SYSCALL_TRACE))
+			&& (current->ptrace & PT_PTRACED))
+		do_syscall_trace();
+}