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-rw-r--r--arch/blackfin/kernel/ptrace.c411
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);
+}