summaryrefslogtreecommitdiffstats
path: root/arch/hexagon/kernel/ptrace.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/hexagon/kernel/ptrace.c')
-rw-r--r--arch/hexagon/kernel/ptrace.c171
1 files changed, 171 insertions, 0 deletions
diff --git a/arch/hexagon/kernel/ptrace.c b/arch/hexagon/kernel/ptrace.c
new file mode 100644
index 000000000..8975f9b4c
--- /dev/null
+++ b/arch/hexagon/kernel/ptrace.c
@@ -0,0 +1,171 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Ptrace support for Hexagon
+ *
+ * Copyright (c) 2010-2013, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/sched/task_stack.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/regset.h>
+#include <linux/user.h>
+#include <linux/elf.h>
+
+#include <asm/user.h>
+
+#if arch_has_single_step()
+/* Both called from ptrace_resume */
+void user_enable_single_step(struct task_struct *child)
+{
+ pt_set_singlestep(task_pt_regs(child));
+ set_tsk_thread_flag(child, TIF_SINGLESTEP);
+}
+
+void user_disable_single_step(struct task_struct *child)
+{
+ pt_clr_singlestep(task_pt_regs(child));
+ clear_tsk_thread_flag(child, TIF_SINGLESTEP);
+}
+#endif
+
+static int genregs_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ struct pt_regs *regs = task_pt_regs(target);
+
+ /* The general idea here is that the copyout must happen in
+ * exactly the same order in which the userspace expects these
+ * regs. Now, the sequence in userspace does not match the
+ * sequence in the kernel, so everything past the 32 gprs
+ * happens one at a time.
+ */
+ membuf_write(&to, &regs->r00, 32*sizeof(unsigned long));
+ /* Must be exactly same sequence as struct user_regs_struct */
+ membuf_store(&to, regs->sa0);
+ membuf_store(&to, regs->lc0);
+ membuf_store(&to, regs->sa1);
+ membuf_store(&to, regs->lc1);
+ membuf_store(&to, regs->m0);
+ membuf_store(&to, regs->m1);
+ membuf_store(&to, regs->usr);
+ membuf_store(&to, regs->preds);
+ membuf_store(&to, regs->gp);
+ membuf_store(&to, regs->ugp);
+ membuf_store(&to, pt_elr(regs)); // pc
+ membuf_store(&to, (unsigned long)pt_cause(regs)); // cause
+ membuf_store(&to, pt_badva(regs)); // badva
+#if CONFIG_HEXAGON_ARCH_VERSION >=4
+ membuf_store(&to, regs->cs0);
+ membuf_store(&to, regs->cs1);
+ return membuf_zero(&to, sizeof(unsigned long));
+#else
+ return membuf_zero(&to, 3 * sizeof(unsigned long));
+#endif
+}
+
+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)
+{
+ int ret;
+ unsigned long bucket;
+ struct pt_regs *regs = task_pt_regs(target);
+
+ if (!regs)
+ return -EIO;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &regs->r00, 0, 32*sizeof(unsigned long));
+
+#define INEXT(KPT_REG, USR_REG) \
+ if (!ret) \
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
+ KPT_REG, offsetof(struct user_regs_struct, USR_REG), \
+ offsetof(struct user_regs_struct, USR_REG) + \
+ sizeof(unsigned long));
+
+ /* Must be exactly same sequence as struct user_regs_struct */
+ INEXT(&regs->sa0, sa0);
+ INEXT(&regs->lc0, lc0);
+ INEXT(&regs->sa1, sa1);
+ INEXT(&regs->lc1, lc1);
+ INEXT(&regs->m0, m0);
+ INEXT(&regs->m1, m1);
+ INEXT(&regs->usr, usr);
+ INEXT(&regs->preds, p3_0);
+ INEXT(&regs->gp, gp);
+ INEXT(&regs->ugp, ugp);
+ INEXT(&pt_elr(regs), pc);
+
+ /* CAUSE and BADVA aren't writeable. */
+ INEXT(&bucket, cause);
+ INEXT(&bucket, badva);
+
+#if CONFIG_HEXAGON_ARCH_VERSION >=4
+ INEXT(&regs->cs0, cs0);
+ INEXT(&regs->cs1, cs1);
+#endif
+
+ /* Ignore the rest, if needed */
+ if (!ret)
+ ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+ offsetof(struct user_regs_struct, pad1), -1);
+
+ if (ret)
+ return ret;
+
+ /*
+ * This is special; SP is actually restored by the VM via the
+ * special event record which is set by the special trap.
+ */
+ regs->hvmer.vmpsp = regs->r29;
+ return 0;
+}
+
+enum hexagon_regset {
+ REGSET_GENERAL,
+};
+
+static const struct user_regset hexagon_regsets[] = {
+ [REGSET_GENERAL] = {
+ .core_note_type = NT_PRSTATUS,
+ .n = ELF_NGREG,
+ .size = sizeof(unsigned long),
+ .align = sizeof(unsigned long),
+ .regset_get = genregs_get,
+ .set = genregs_set,
+ },
+};
+
+static const struct user_regset_view hexagon_user_view = {
+ .name = "hexagon",
+ .e_machine = ELF_ARCH,
+ .ei_osabi = ELF_OSABI,
+ .regsets = hexagon_regsets,
+ .e_flags = ELF_CORE_EFLAGS,
+ .n = ARRAY_SIZE(hexagon_regsets)
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+ return &hexagon_user_view;
+}
+
+void ptrace_disable(struct task_struct *child)
+{
+ /* Boilerplate - resolves to null inline if no HW single-step */
+ user_disable_single_step(child);
+}
+
+long arch_ptrace(struct task_struct *child, long request,
+ unsigned long addr, unsigned long data)
+{
+ return ptrace_request(child, request, addr, data);
+}