Initial import

1 files changed, 411 insertions, 0 deletions

diff --git a/arch/blackfin/kernel/ptrace.c b/arch/blackfin/kernel/ptrace.c
new file mode 100644
index 000000000..8b8fe671b
--- /dev/null
+++ b/arch/blackfin/kernel/ptrace.c
@@ -0,0 +1,411 @@
+/*
+ * linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
+ * these modifications are Copyright 2004-2010 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/elf.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/user.h>
+#include <linux/regset.h>
+#include <linux/signal.h>
+#include <linux/tracehook.h>
+#include <linux/uaccess.h>
+
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/processor.h>
+#include <asm/asm-offsets.h>
+#include <asm/dma.h>
+#include <asm/fixed_code.h>
+#include <asm/cacheflush.h>
+#include <asm/mem_map.h>
+#include <asm/mmu_context.h>
+
+/*
+ * does not yet catch signals sent when the child dies.
+ * in exit.c or in signal.c.
+ */
+
+/*
+ * Get contents of register REGNO in task TASK.
+ */
+static inline long
+get_reg(struct task_struct *task, unsigned long regno,
+	unsigned long __user *datap)
+{
+	long tmp;
+	struct pt_regs *regs = task_pt_regs(task);
+
+	if (regno & 3 || regno > PT_LAST_PSEUDO)
+		return -EIO;
+
+	switch (regno) {
+	case PT_TEXT_ADDR:
+		tmp = task->mm->start_code;
+		break;
+	case PT_TEXT_END_ADDR:
+		tmp = task->mm->end_code;
+		break;
+	case PT_DATA_ADDR:
+		tmp = task->mm->start_data;
+		break;
+	case PT_USP:
+		tmp = task->thread.usp;
+		break;
+	default:
+		if (regno < sizeof(*regs)) {
+			void *reg_ptr = regs;
+			tmp = *(long *)(reg_ptr + regno);
+		} else
+			return -EIO;
+	}
+
+	return put_user(tmp, datap);
+}
+
+/*
+ * Write contents of register REGNO in task TASK.
+ */
+static inline int
+put_reg(struct task_struct *task, unsigned long regno, unsigned long data)
+{
+	struct pt_regs *regs = task_pt_regs(task);
+
+	if (regno & 3 || regno > PT_LAST_PSEUDO)
+		return -EIO;
+
+	switch (regno) {
+	case PT_PC:
+		/*********************************************************************/
+		/* At this point the kernel is most likely in exception.             */
+		/* The RETX register will be used to populate the pc of the process. */
+		/*********************************************************************/
+		regs->retx = data;
+		regs->pc = data;
+		break;
+	case PT_RETX:
+		break;		/* regs->retx = data; break; */
+	case PT_USP:
+		regs->usp = data;
+		task->thread.usp = data;
+		break;
+	case PT_SYSCFG:	/* don't let userspace screw with this */
+		if ((data & ~1) != 0x6)
+			pr_warning("ptrace: ignore syscfg write of %#lx\n", data);
+		break;		/* regs->syscfg = data; break; */
+	default:
+		if (regno < sizeof(*regs)) {
+			void *reg_offset = regs;
+			*(long *)(reg_offset + regno) = data;
+		}
+		/* Ignore writes to pseudo registers */
+	}
+
+	return 0;
+}
+
+/*
+ * check that an address falls within the bounds of the target process's memory mappings
+ */
+int
+is_user_addr_valid(struct task_struct *child, unsigned long start, unsigned long len)
+{
+	bool valid;
+	struct vm_area_struct *vma;
+	struct sram_list_struct *sraml;
+
+	/* overflow */
+	if (start + len < start)
+		return -EIO;
+
+	down_read(&child->mm->mmap_sem);
+	vma = find_vma(child->mm, start);
+	valid = vma && start >= vma->vm_start && start + len <= vma->vm_end;
+	up_read(&child->mm->mmap_sem);
+	if (valid)
+		return 0;
+
+	for (sraml = child->mm->context.sram_list; sraml; sraml = sraml->next)
+		if (start >= (unsigned long)sraml->addr
+		    && start + len < (unsigned long)sraml->addr + sraml->length)
+			return 0;
+
+	if (start >= FIXED_CODE_START && start + len < FIXED_CODE_END)
+		return 0;
+
+#ifdef CONFIG_APP_STACK_L1
+	if (child->mm->context.l1_stack_save)
+		if (start >= (unsigned long)l1_stack_base &&
+			start + len < (unsigned long)l1_stack_base + l1_stack_len)
+			return 0;
+#endif
+
+	return -EIO;
+}
+
+/*
+ * retrieve the contents of Blackfin userspace general registers
+ */
+static int genregs_get(struct task_struct *target,
+		       const struct user_regset *regset,
+		       unsigned int pos, unsigned int count,
+		       void *kbuf, void __user *ubuf)
+{
+	struct pt_regs *regs = task_pt_regs(target);
+	int ret;
+
+	/* This sucks ... */
+	regs->usp = target->thread.usp;
+
+	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+				  regs, 0, sizeof(*regs));
+	if (ret < 0)
+		return ret;
+
+	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
+					sizeof(*regs), -1);
+}
+
+/*
+ * update the contents of the Blackfin userspace general registers
+ */
+static int genregs_set(struct task_struct *target,
+		       const struct user_regset *regset,
+		       unsigned int pos, unsigned int count,
+		       const void *kbuf, const void __user *ubuf)
+{
+	struct pt_regs *regs = task_pt_regs(target);
+	int ret;
+
+	/* Don't let people set SYSCFG (it's at the end of pt_regs) */
+	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+				 regs, 0, PT_SYSCFG);
+	if (ret < 0)
+		return ret;
+
+	/* This sucks ... */
+	target->thread.usp = regs->usp;
+	/* regs->retx = regs->pc; */
+
+	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+					PT_SYSCFG, -1);
+}
+
+/*
+ * Define the register sets available on the Blackfin under Linux
+ */
+enum bfin_regset {
+	REGSET_GENERAL,
+};
+
+static const struct user_regset bfin_regsets[] = {
+	[REGSET_GENERAL] = {
+		.core_note_type = NT_PRSTATUS,
+		.n              = sizeof(struct pt_regs) / sizeof(long),
+		.size           = sizeof(long),
+		.align          = sizeof(long),
+		.get            = genregs_get,
+		.set            = genregs_set,
+	},
+};
+
+static const struct user_regset_view user_bfin_native_view = {
+	.name      = "Blackfin",
+	.e_machine = EM_BLACKFIN,
+	.regsets   = bfin_regsets,
+	.n         = ARRAY_SIZE(bfin_regsets),
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+	return &user_bfin_native_view;
+}
+
+void user_enable_single_step(struct task_struct *child)
+{
+	struct pt_regs *regs = task_pt_regs(child);
+	regs->syscfg |= SYSCFG_SSSTEP;
+
+	set_tsk_thread_flag(child, TIF_SINGLESTEP);
+}
+
+void user_disable_single_step(struct task_struct *child)
+{
+	struct pt_regs *regs = task_pt_regs(child);
+	regs->syscfg &= ~SYSCFG_SSSTEP;
+
+	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
+}
+
+long arch_ptrace(struct task_struct *child, long request,
+		 unsigned long addr, unsigned long data)
+{
+	int ret;
+	unsigned long __user *datap = (unsigned long __user *)data;
+	void *paddr = (void *)addr;
+
+	switch (request) {
+		/* when I and D space are separate, these will need to be fixed. */
+	case PTRACE_PEEKDATA:
+		pr_debug("ptrace: PEEKDATA\n");
+		/* fall through */
+	case PTRACE_PEEKTEXT:	/* read word at location addr. */
+		{
+			unsigned long tmp = 0;
+			int copied = 0, to_copy = sizeof(tmp);
+
+			ret = -EIO;
+			pr_debug("ptrace: PEEKTEXT at addr 0x%08lx + %i\n", addr, to_copy);
+			if (is_user_addr_valid(child, addr, to_copy) < 0)
+				break;
+			pr_debug("ptrace: user address is valid\n");
+
+			switch (bfin_mem_access_type(addr, to_copy)) {
+			case BFIN_MEM_ACCESS_CORE:
+			case BFIN_MEM_ACCESS_CORE_ONLY:
+				copied = access_process_vm(child, addr, &tmp,
+				                           to_copy, 0);
+				if (copied)
+					break;
+
+				/* hrm, why didn't that work ... maybe no mapping */
+				if (addr >= FIXED_CODE_START &&
+				    addr + to_copy <= FIXED_CODE_END) {
+					copy_from_user_page(0, 0, 0, &tmp, paddr, to_copy);
+					copied = to_copy;
+				} else if (addr >= BOOT_ROM_START) {
+					memcpy(&tmp, paddr, to_copy);
+					copied = to_copy;
+				}
+
+				break;
+			case BFIN_MEM_ACCESS_DMA:
+				if (safe_dma_memcpy(&tmp, paddr, to_copy))
+					copied = to_copy;
+				break;
+			case BFIN_MEM_ACCESS_ITEST:
+				if (isram_memcpy(&tmp, paddr, to_copy))
+					copied = to_copy;
+				break;
+			default:
+				copied = 0;
+				break;
+			}
+
+			pr_debug("ptrace: copied size %d [0x%08lx]\n", copied, tmp);
+			if (copied == to_copy)
+				ret = put_user(tmp, datap);
+			break;
+		}
+
+		/* when I and D space are separate, this will have to be fixed. */
+	case PTRACE_POKEDATA:
+		pr_debug("ptrace: PTRACE_PEEKDATA\n");
+		/* fall through */
+	case PTRACE_POKETEXT:	/* write the word at location addr. */
+		{
+			int copied = 0, to_copy = sizeof(data);
+
+			ret = -EIO;
+			pr_debug("ptrace: POKETEXT at addr 0x%08lx + %i bytes %lx\n",
+			         addr, to_copy, data);
+			if (is_user_addr_valid(child, addr, to_copy) < 0)
+				break;
+			pr_debug("ptrace: user address is valid\n");
+
+			switch (bfin_mem_access_type(addr, to_copy)) {
+			case BFIN_MEM_ACCESS_CORE:
+			case BFIN_MEM_ACCESS_CORE_ONLY:
+				copied = access_process_vm(child, addr, &data,
+				                           to_copy, 1);
+				break;
+			case BFIN_MEM_ACCESS_DMA:
+				if (safe_dma_memcpy(paddr, &data, to_copy))
+					copied = to_copy;
+				break;
+			case BFIN_MEM_ACCESS_ITEST:
+				if (isram_memcpy(paddr, &data, to_copy))
+					copied = to_copy;
+				break;
+			default:
+				copied = 0;
+				break;
+			}
+
+			pr_debug("ptrace: copied size %d\n", copied);
+			if (copied == to_copy)
+				ret = 0;
+			break;
+		}
+
+	case PTRACE_PEEKUSR:
+		switch (addr) {
+#ifdef CONFIG_BINFMT_ELF_FDPIC	/* backwards compat */
+		case PT_FDPIC_EXEC:
+			request = PTRACE_GETFDPIC;
+			addr = PTRACE_GETFDPIC_EXEC;
+			goto case_default;
+		case PT_FDPIC_INTERP:
+			request = PTRACE_GETFDPIC;
+			addr = PTRACE_GETFDPIC_INTERP;
+			goto case_default;
+#endif
+		default:
+			ret = get_reg(child, addr, datap);
+		}
+		pr_debug("ptrace: PEEKUSR reg %li with %#lx = %i\n", addr, data, ret);
+		break;
+
+	case PTRACE_POKEUSR:
+		ret = put_reg(child, addr, data);
+		pr_debug("ptrace: POKEUSR reg %li with %li = %i\n", addr, data, ret);
+		break;
+
+	case PTRACE_GETREGS:
+		pr_debug("ptrace: PTRACE_GETREGS\n");
+		return copy_regset_to_user(child, &user_bfin_native_view,
+					   REGSET_GENERAL,
+					   0, sizeof(struct pt_regs),
+					   datap);
+
+	case PTRACE_SETREGS:
+		pr_debug("ptrace: PTRACE_SETREGS\n");
+		return copy_regset_from_user(child, &user_bfin_native_view,
+					     REGSET_GENERAL,
+					     0, sizeof(struct pt_regs),
+					     datap);
+
+	case_default:
+	default:
+		ret = ptrace_request(child, request, addr, data);
+		break;
+	}
+
+	return ret;
+}
+
+asmlinkage int syscall_trace_enter(struct pt_regs *regs)
+{
+	int ret = 0;
+
+	if (test_thread_flag(TIF_SYSCALL_TRACE))
+		ret = tracehook_report_syscall_entry(regs);
+
+	return ret;
+}
+
+asmlinkage void syscall_trace_leave(struct pt_regs *regs)
+{
+	int step;
+
+	step = test_thread_flag(TIF_SINGLESTEP);
+	if (step || test_thread_flag(TIF_SYSCALL_TRACE))
+		tracehook_report_syscall_exit(regs, step);
+}