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Diffstat (limited to 'arch/tile/kernel/ptrace.c')
-rw-r--r--arch/tile/kernel/ptrace.c140
1 files changed, 113 insertions, 27 deletions
diff --git a/arch/tile/kernel/ptrace.c b/arch/tile/kernel/ptrace.c
index e92e40527d6d..9835312d5a91 100644
--- a/arch/tile/kernel/ptrace.c
+++ b/arch/tile/kernel/ptrace.c
@@ -19,7 +19,10 @@
#include <linux/kprobes.h>
#include <linux/compat.h>
#include <linux/uaccess.h>
+#include <linux/regset.h>
+#include <linux/elf.h>
#include <asm/traps.h>
+#include <arch/chip.h>
void user_enable_single_step(struct task_struct *child)
{
@@ -45,6 +48,100 @@ void ptrace_disable(struct task_struct *child)
clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
}
+/*
+ * Get registers from task and ready the result for userspace.
+ * Note that we localize the API issues to getregs() and putregs() at
+ * some cost in performance, e.g. we need a full pt_regs copy for
+ * PEEKUSR, and two copies for POKEUSR. But in general we expect
+ * GETREGS/PUTREGS to be the API of choice anyway.
+ */
+static char *getregs(struct task_struct *child, struct pt_regs *uregs)
+{
+ *uregs = *task_pt_regs(child);
+
+ /* Set up flags ABI bits. */
+ uregs->flags = 0;
+#ifdef CONFIG_COMPAT
+ if (task_thread_info(child)->status & TS_COMPAT)
+ uregs->flags |= PT_FLAGS_COMPAT;
+#endif
+
+ return (char *)uregs;
+}
+
+/* Put registers back to task. */
+static void putregs(struct task_struct *child, struct pt_regs *uregs)
+{
+ struct pt_regs *regs = task_pt_regs(child);
+
+ /* Don't allow overwriting the kernel-internal flags word. */
+ uregs->flags = regs->flags;
+
+ /* Only allow setting the ICS bit in the ex1 word. */
+ uregs->ex1 = PL_ICS_EX1(USER_PL, EX1_ICS(uregs->ex1));
+
+ *regs = *uregs;
+}
+
+enum tile_regset {
+ REGSET_GPR,
+};
+
+static int tile_gpr_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;
+
+ getregs(target, &regs);
+
+ return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &regs, 0,
+ sizeof(regs));
+}
+
+static int tile_gpr_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ int ret;
+ struct pt_regs regs;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &regs, 0,
+ sizeof(regs));
+ if (ret)
+ return ret;
+
+ putregs(target, &regs);
+
+ return 0;
+}
+
+static const struct user_regset tile_user_regset[] = {
+ [REGSET_GPR] = {
+ .core_note_type = NT_PRSTATUS,
+ .n = ELF_NGREG,
+ .size = sizeof(elf_greg_t),
+ .align = sizeof(elf_greg_t),
+ .get = tile_gpr_get,
+ .set = tile_gpr_set,
+ },
+};
+
+static const struct user_regset_view tile_user_regset_view = {
+ .name = CHIP_ARCH_NAME,
+ .e_machine = ELF_ARCH,
+ .ei_osabi = ELF_OSABI,
+ .regsets = tile_user_regset,
+ .n = ARRAY_SIZE(tile_user_regset),
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+ return &tile_user_regset_view;
+}
+
long arch_ptrace(struct task_struct *child, long request,
unsigned long addr, unsigned long data)
{
@@ -53,14 +150,13 @@ long arch_ptrace(struct task_struct *child, long request,
long ret = -EIO;
char *childreg;
struct pt_regs copyregs;
- int ex1_offset;
switch (request) {
case PTRACE_PEEKUSR: /* Read register from pt_regs. */
if (addr >= PTREGS_SIZE)
break;
- childreg = (char *)task_pt_regs(child) + addr;
+ childreg = getregs(child, &copyregs) + addr;
#ifdef CONFIG_COMPAT
if (is_compat_task()) {
if (addr & (sizeof(compat_long_t)-1))
@@ -79,17 +175,7 @@ long arch_ptrace(struct task_struct *child, long request,
case PTRACE_POKEUSR: /* Write register in pt_regs. */
if (addr >= PTREGS_SIZE)
break;
- childreg = (char *)task_pt_regs(child) + addr;
-
- /* Guard against overwrites of the privilege level. */
- ex1_offset = PTREGS_OFFSET_EX1;
-#if defined(CONFIG_COMPAT) && defined(__BIG_ENDIAN)
- if (is_compat_task()) /* point at low word */
- ex1_offset += sizeof(compat_long_t);
-#endif
- if (addr == ex1_offset)
- data = PL_ICS_EX1(USER_PL, EX1_ICS(data));
-
+ childreg = getregs(child, &copyregs) + addr;
#ifdef CONFIG_COMPAT
if (is_compat_task()) {
if (addr & (sizeof(compat_long_t)-1))
@@ -102,24 +188,20 @@ long arch_ptrace(struct task_struct *child, long request,
break;
*(long *)childreg = data;
}
+ putregs(child, &copyregs);
ret = 0;
break;
case PTRACE_GETREGS: /* Get all registers from the child. */
- if (copy_to_user(datap, task_pt_regs(child),
- sizeof(struct pt_regs)) == 0) {
- ret = 0;
- }
+ ret = copy_regset_to_user(child, &tile_user_regset_view,
+ REGSET_GPR, 0,
+ sizeof(struct pt_regs), datap);
break;
case PTRACE_SETREGS: /* Set all registers in the child. */
- if (copy_from_user(&copyregs, datap,
- sizeof(struct pt_regs)) == 0) {
- copyregs.ex1 =
- PL_ICS_EX1(USER_PL, EX1_ICS(copyregs.ex1));
- *task_pt_regs(child) = copyregs;
- ret = 0;
- }
+ ret = copy_regset_from_user(child, &tile_user_regset_view,
+ REGSET_GPR, 0,
+ sizeof(struct pt_regs), datap);
break;
case PTRACE_GETFPREGS: /* Get the child FPU state. */
@@ -128,12 +210,16 @@ long arch_ptrace(struct task_struct *child, long request,
case PTRACE_SETOPTIONS:
/* Support TILE-specific ptrace options. */
- child->ptrace &= ~PT_TRACE_MASK_TILE;
+ BUILD_BUG_ON(PTRACE_O_MASK_TILE & PTRACE_O_MASK);
tmp = data & PTRACE_O_MASK_TILE;
data &= ~PTRACE_O_MASK_TILE;
ret = ptrace_request(child, request, addr, data);
- if (tmp & PTRACE_O_TRACEMIGRATE)
- child->ptrace |= PT_TRACE_MIGRATE;
+ if (ret == 0) {
+ unsigned int flags = child->ptrace;
+ flags &= ~(PTRACE_O_MASK_TILE << PT_OPT_FLAG_SHIFT);
+ flags |= (tmp << PT_OPT_FLAG_SHIFT);
+ child->ptrace = flags;
+ }
break;
default: