diff options
Diffstat (limited to 'arch/hexagon/kernel/ptrace.c')
| -rw-r--r-- | arch/hexagon/kernel/ptrace.c | 171 |
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, ®s->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, + ®s->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(®s->sa0, sa0); + INEXT(®s->lc0, lc0); + INEXT(®s->sa1, sa1); + INEXT(®s->lc1, lc1); + INEXT(®s->m0, m0); + INEXT(®s->m1, m1); + INEXT(®s->usr, usr); + INEXT(®s->preds, p3_0); + INEXT(®s->gp, gp); + INEXT(®s->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(®s->cs0, cs0); + INEXT(®s->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); +} |