powerpc: Extended ptrace interface From: Torez Smith <lnxto...@linux.vnet.ibm.com>
Add a new extended ptrace interface so that user-space has a single interface for powerpc, without having to know the specific layout of the debug registers. Implement: PPC_PTRACE_GETHWDEBUGINFO PPC_PTRACE_SETHWDEBUG PPC_PTRACE_DELHWDEBUG Signed-off-by: Dave Kleikamp <sha...@linux.vnet.ibm.com> Signed-off-by: Torez Smith <lnxto...@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <b...@kernel.crashing.org> Cc: Thiago Jung Bauermann <bauer...@br.ibm.com> Cc: Sergio Durigan Junior <sergi...@br.ibm.com> Cc: David Gibson <d...@au1.ibm.com> Cc: linuxppc-dev list <linuxppc-...@ozlabs.org> --- arch/powerpc/include/asm/ptrace.h | 75 ++++++++++++++++++++++++++++++++ arch/powerpc/kernel/ptrace.c | 88 +++++++++++++++++++++++++++++++++++++ 2 files changed, 163 insertions(+), 0 deletions(-) diff --git a/arch/powerpc/include/asm/ptrace.h b/arch/powerpc/include/asm/ptrace.h index 8c34149..7ae887b 100644 --- a/arch/powerpc/include/asm/ptrace.h +++ b/arch/powerpc/include/asm/ptrace.h @@ -24,6 +24,12 @@ * 2 of the License, or (at your option) any later version. */ +#ifdef __KERNEL__ +#include <linux/types.h> +#else +#include <stdint.h> +#endif + #ifndef __ASSEMBLY__ struct pt_regs { @@ -292,4 +298,73 @@ extern void user_disable_single_step(struct task_struct *); #define PTRACE_SINGLEBLOCK 0x100 /* resume execution until next branch */ +#define PPC_PTRACE_GETHWDBGINFO 0x89 +#define PPC_PTRACE_SETHWDEBUG 0x88 +#define PPC_PTRACE_DELHWDEBUG 0x87 + +#ifndef __ASSEMBLY__ + +struct ppc_debug_info { + uint32_t version; /* Only version 1 exists to date */ + uint32_t num_instruction_bps; + uint32_t num_data_bps; + uint32_t num_condition_regs; + uint32_t data_bp_alignment; + uint32_t sizeof_condition; /* size of the DVC register */ + uint64_t features; +}; + +#endif /* __ASSEMBLY__ */ + +/* + * features will have bits indication whether there is support for: + */ +#define PPC_DEBUG_FEATURE_INSN_BP_RANGE 0x1 +#define PPC_DEBUG_FEATURE_INSN_BP_MASK 0x2 +#define PPC_DEBUG_FEATURE_DATA_BP_RANGE 0x4 +#define PPC_DEBUG_FEATURE_DATA_BP_MASK 0x8 + +#ifndef __ASSEMBLY__ + +struct ppc_hw_breakpoint { + uint32_t version; /* currently, version must be 1 */ + uint32_t trigger_type; /* only some combinations allowed */ + uint32_t addr_mode; /* address match mode */ + uint32_t condition_mode; /* break/watchpoint condition flags */ + uint64_t addr; /* break/watchpoint address */ + uint64_t addr2; /* range end or mask */ + uint64_t condition_value; /* contents of the DVC register */ +}; + +#endif /* __ASSEMBLY__ */ + +/* + * Trigger Type + */ +#define PPC_BREAKPOINT_TRIGGER_EXECUTE 0x1 +#define PPC_BREAKPOINT_TRIGGER_READ 0x2 +#define PPC_BREAKPOINT_TRIGGER_WRITE 0x4 +#define PPC_BREAKPOINT_TRIGGER_RW 0x6 + +/* + * Address Mode + */ +#define PPC_BREAKPOINT_MODE_EXACT 0x0 +#define PPC_BREAKPOINT_MODE_RANGE_INCLUSIVE 0x1 +#define PPC_BREAKPOINT_MODE_RANGE_EXCLUSIVE 0x2 +#define PPC_BREAKPOINT_MODE_MASK 0x3 + +/* + * Condition Mode + */ +#define PPC_BREAKPOINT_CONDITION_NONE 0x0 +#define PPC_BREAKPOINT_CONDITION_AND 0x1 +#define PPC_BREAKPOINT_CONDITION_EXACT 0x1 +#define PPC_BREAKPOINT_CONDITION_OR 0x2 +#define PPC_BREAKPOINT_CONDITION_AND_OR 0x3 +#define PPC_BREAKPOINT_CONDITION_BE_ALL 0x00ff0000 +#define PPC_BREAKPOINT_CONDITION_BE_SHIFT 16 +#define PPC_BREAKPOINT_CONDITION_BE(n) \ + (1<<((n)+PPC_BREAKPOINT_CONDITION_BE_SHIFT)) + #endif /* _ASM_POWERPC_PTRACE_H */ diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c index ef14988..6be2ce0 100644 --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c @@ -839,6 +839,50 @@ void ptrace_disable(struct task_struct *child) user_disable_single_step(child); } +static long ppc_set_hwdebug(struct task_struct *child, + struct ppc_hw_breakpoint *bp_info) +{ + /* + * We currently 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->trigger_type != PPC_BREAKPOINT_TRIGGER_WRITE) || + (bp_info->addr_mode != PPC_BREAKPOINT_MODE_EXACT) || + (bp_info->condition_mode != PPC_BREAKPOINT_CONDITION_NONE)) + return -EINVAL; + + if (child->thread.dabr) + return -ENOSPC; + + if ((unsigned long)bp_info->addr >= TASK_SIZE) + return -EIO; + + child->thread.dabr = (unsigned long)bp_info->addr; +#ifdef CONFIG_BOOKE + child->thread.dbcr0 = DBCR0_IDM; + if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_READ) + child->thread.dbcr0 |= DBSR_DAC1R; + if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_WRITE) + child->thread.dbcr0 |= DBSR_DAC1W; + child->thread.regs->msr |= MSR_DE; +#endif + return 1; +} + +static long ppc_del_hwdebug(struct task_struct *child, long addr, long data) +{ + if ((data != 1) || (child->thread.dabr == 0)) + return -EINVAL; + + child->thread.dabr = 0; +#ifdef CONFIG_BOOKE + child->thread.dbcr0 &= ~(DBSR_DAC1R | DBSR_DAC1W | DBCR0_IDM); + child->thread.regs->msr &= ~MSR_DE; +#endif + return 0; +} + /* * Here are the old "legacy" powerpc specific getregs/setregs ptrace calls, * we mark them as obsolete now, they will be removed in a future version @@ -932,6 +976,50 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) break; } + case PPC_PTRACE_GETHWDBGINFO: { + struct ppc_debug_info dbginfo; + + dbginfo.version = 1; + dbginfo.num_instruction_bps = 0; + dbginfo.num_data_bps = 1; + dbginfo.num_condition_regs = 0; +#ifdef CONFIG_PPC64 + dbginfo.data_bp_alignment = 8; +#else + dbginfo.data_bp_alignment = 0; +#endif + dbginfo.sizeof_condition = 0; + dbginfo.features = 0; + + if (!access_ok(VERIFY_WRITE, data, + sizeof(struct ppc_debug_info))) + return -EFAULT; + ret = __copy_to_user((struct ppc_debug_info __user *)data, + &dbginfo, sizeof(struct ppc_debug_info)) ? + -EFAULT : 0; + break; + } + + case PPC_PTRACE_SETHWDEBUG: { + struct ppc_hw_breakpoint bp_info; + + if (!access_ok(VERIFY_READ, data, + sizeof(struct ppc_hw_breakpoint))) + return -EFAULT; + ret = __copy_from_user(&bp_info, + (struct ppc_hw_breakpoint __user *)data, + sizeof(struct ppc_hw_breakpoint)) ? + -EFAULT : 0; + if (!ret) + ret = ppc_set_hwdebug(child, &bp_info); + break; + } + + case PPC_PTRACE_DELHWDEBUG: { + ret = ppc_del_hwdebug(child, addr, data); + break; + } + case PTRACE_GET_DEBUGREG: { ret = -EINVAL; /* We only support one DABR and no IABRS at the moment */ -- Dave Kleikamp IBM Linux Technology Center _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev