diff options
Diffstat (limited to 'arch/powerpc/kernel/ptrace/ptrace-noadv.c')
| -rw-r--r-- | arch/powerpc/kernel/ptrace/ptrace-noadv.c | 265 |
1 files changed, 265 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/ptrace/ptrace-noadv.c b/arch/powerpc/kernel/ptrace/ptrace-noadv.c new file mode 100644 index 000000000000..f87e7c5c3bf3 --- /dev/null +++ b/arch/powerpc/kernel/ptrace/ptrace-noadv.c @@ -0,0 +1,265 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include <linux/regset.h> +#include <linux/hw_breakpoint.h> + +#include <asm/debug.h> + +#include "ptrace-decl.h" + +void user_enable_single_step(struct task_struct *task) +{ + struct pt_regs *regs = task->thread.regs; + + if (regs != NULL) { + regs->msr &= ~MSR_BE; + regs->msr |= MSR_SE; + } + set_tsk_thread_flag(task, TIF_SINGLESTEP); +} + +void user_enable_block_step(struct task_struct *task) +{ + struct pt_regs *regs = task->thread.regs; + + if (regs != NULL) { + regs->msr &= ~MSR_SE; + regs->msr |= MSR_BE; + } + set_tsk_thread_flag(task, TIF_SINGLESTEP); +} + +void user_disable_single_step(struct task_struct *task) +{ + struct pt_regs *regs = task->thread.regs; + + if (regs != NULL) + regs->msr &= ~(MSR_SE | MSR_BE); + + clear_tsk_thread_flag(task, TIF_SINGLESTEP); +} + +void ppc_gethwdinfo(struct ppc_debug_info *dbginfo) +{ + dbginfo->version = 1; + dbginfo->num_instruction_bps = 0; + if (ppc_breakpoint_available()) + dbginfo->num_data_bps = 1; + else + dbginfo->num_data_bps = 0; + dbginfo->num_condition_regs = 0; + dbginfo->data_bp_alignment = sizeof(long); + dbginfo->sizeof_condition = 0; + if (IS_ENABLED(CONFIG_HAVE_HW_BREAKPOINT)) { + dbginfo->features = PPC_DEBUG_FEATURE_DATA_BP_RANGE; + if (dawr_enabled()) + dbginfo->features |= PPC_DEBUG_FEATURE_DATA_BP_DAWR; + } else { + dbginfo->features = 0; + } +} + +int ptrace_get_debugreg(struct task_struct *child, unsigned long addr, + unsigned long __user *datalp) +{ + unsigned long dabr_fake; + + /* We only support one DABR and no IABRS at the moment */ + if (addr > 0) + return -EINVAL; + dabr_fake = ((child->thread.hw_brk.address & (~HW_BRK_TYPE_DABR)) | + (child->thread.hw_brk.type & HW_BRK_TYPE_DABR)); + return put_user(dabr_fake, datalp); +} + +int ptrace_set_debugreg(struct task_struct *task, unsigned long addr, unsigned long data) +{ +#ifdef CONFIG_HAVE_HW_BREAKPOINT + int ret; + struct thread_struct *thread = &task->thread; + struct perf_event *bp; + struct perf_event_attr attr; +#endif /* CONFIG_HAVE_HW_BREAKPOINT */ + bool set_bp = true; + struct arch_hw_breakpoint hw_brk; + + /* For ppc64 we support one DABR and no IABR's at the moment (ppc64). + * For embedded processors we support one DAC and no IAC's at the + * moment. + */ + if (addr > 0) + return -EINVAL; + + /* The bottom 3 bits in dabr are flags */ + if ((data & ~0x7UL) >= TASK_SIZE) + return -EIO; + + /* For processors using DABR (i.e. 970), the bottom 3 bits are flags. + * It was assumed, on previous implementations, that 3 bits were + * passed together with the data address, fitting the design of the + * DABR register, as follows: + * + * bit 0: Read flag + * bit 1: Write flag + * bit 2: Breakpoint translation + * + * Thus, we use them here as so. + */ + + /* Ensure breakpoint translation bit is set */ + if (data && !(data & HW_BRK_TYPE_TRANSLATE)) + return -EIO; + hw_brk.address = data & (~HW_BRK_TYPE_DABR); + hw_brk.type = (data & HW_BRK_TYPE_DABR) | HW_BRK_TYPE_PRIV_ALL; + hw_brk.len = DABR_MAX_LEN; + hw_brk.hw_len = DABR_MAX_LEN; + set_bp = (data) && (hw_brk.type & HW_BRK_TYPE_RDWR); +#ifdef CONFIG_HAVE_HW_BREAKPOINT + bp = thread->ptrace_bps[0]; + if (!set_bp) { + if (bp) { + unregister_hw_breakpoint(bp); + thread->ptrace_bps[0] = NULL; + } + return 0; + } + if (bp) { + attr = bp->attr; + attr.bp_addr = hw_brk.address; + attr.bp_len = DABR_MAX_LEN; + arch_bp_generic_fields(hw_brk.type, &attr.bp_type); + + /* Enable breakpoint */ + attr.disabled = false; + + ret = modify_user_hw_breakpoint(bp, &attr); + if (ret) + return ret; + + thread->ptrace_bps[0] = bp; + thread->hw_brk = hw_brk; + return 0; + } + + /* Create a new breakpoint request if one doesn't exist already */ + hw_breakpoint_init(&attr); + attr.bp_addr = hw_brk.address; + attr.bp_len = DABR_MAX_LEN; + arch_bp_generic_fields(hw_brk.type, + &attr.bp_type); + + thread->ptrace_bps[0] = bp = register_user_hw_breakpoint(&attr, + ptrace_triggered, NULL, task); + if (IS_ERR(bp)) { + thread->ptrace_bps[0] = NULL; + return PTR_ERR(bp); + } + +#else /* !CONFIG_HAVE_HW_BREAKPOINT */ + if (set_bp && (!ppc_breakpoint_available())) + return -ENODEV; +#endif /* CONFIG_HAVE_HW_BREAKPOINT */ + task->thread.hw_brk = hw_brk; + return 0; +} + +long ppc_set_hwdebug(struct task_struct *child, struct ppc_hw_breakpoint *bp_info) +{ +#ifdef CONFIG_HAVE_HW_BREAKPOINT + int len = 0; + struct thread_struct *thread = &child->thread; + struct perf_event *bp; + struct perf_event_attr attr; +#endif /* CONFIG_HAVE_HW_BREAKPOINT */ + struct arch_hw_breakpoint brk; + + if (bp_info->version != 1) + return -ENOTSUPP; + /* + * We only support one data breakpoint + */ + if ((bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_RW) == 0 || + (bp_info->trigger_type & ~PPC_BREAKPOINT_TRIGGER_RW) != 0 || + bp_info->condition_mode != PPC_BREAKPOINT_CONDITION_NONE) + return -EINVAL; + + if ((unsigned long)bp_info->addr >= TASK_SIZE) + return -EIO; + + brk.address = bp_info->addr & ~HW_BREAKPOINT_ALIGN; + brk.type = HW_BRK_TYPE_TRANSLATE; + brk.len = DABR_MAX_LEN; + if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_READ) + brk.type |= HW_BRK_TYPE_READ; + if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_WRITE) + brk.type |= HW_BRK_TYPE_WRITE; +#ifdef CONFIG_HAVE_HW_BREAKPOINT + if (bp_info->addr_mode == PPC_BREAKPOINT_MODE_RANGE_INCLUSIVE) + len = bp_info->addr2 - bp_info->addr; + else if (bp_info->addr_mode == PPC_BREAKPOINT_MODE_EXACT) + len = 1; + else + return -EINVAL; + bp = thread->ptrace_bps[0]; + if (bp) + return -ENOSPC; + + /* Create a new breakpoint request if one doesn't exist already */ + hw_breakpoint_init(&attr); + attr.bp_addr = (unsigned long)bp_info->addr; + attr.bp_len = len; + arch_bp_generic_fields(brk.type, &attr.bp_type); + + bp = register_user_hw_breakpoint(&attr, ptrace_triggered, NULL, child); + thread->ptrace_bps[0] = bp; + if (IS_ERR(bp)) { + thread->ptrace_bps[0] = NULL; + return PTR_ERR(bp); + } + + return 1; +#endif /* CONFIG_HAVE_HW_BREAKPOINT */ + + if (bp_info->addr_mode != PPC_BREAKPOINT_MODE_EXACT) + return -EINVAL; + + if (child->thread.hw_brk.address) + return -ENOSPC; + + if (!ppc_breakpoint_available()) + return -ENODEV; + + child->thread.hw_brk = brk; + + return 1; +} + +long ppc_del_hwdebug(struct task_struct *child, long data) +{ +#ifdef CONFIG_HAVE_HW_BREAKPOINT + int ret = 0; + struct thread_struct *thread = &child->thread; + struct perf_event *bp; +#endif /* CONFIG_HAVE_HW_BREAKPOINT */ + if (data != 1) + return -EINVAL; + +#ifdef CONFIG_HAVE_HW_BREAKPOINT + bp = thread->ptrace_bps[0]; + if (bp) { + unregister_hw_breakpoint(bp); + thread->ptrace_bps[0] = NULL; + } else { + ret = -ENOENT; + } + return ret; +#else /* CONFIG_HAVE_HW_BREAKPOINT */ + if (child->thread.hw_brk.address == 0) + return -ENOENT; + + child->thread.hw_brk.address = 0; + child->thread.hw_brk.type = 0; +#endif /* CONFIG_HAVE_HW_BREAKPOINT */ + + return 0; +} |