From f8bf33b5aea6b8cb65900153583d9675eae345df Mon Sep 17 00:00:00 2001 From: Atle Nissestad Date: Sun, 16 Dec 2007 17:34:35 +0100 Subject: [PATCH] nios2: Fixed ptrace register handling The ptrace syscall (at least when it comes to register/memory read/write) should now for the 1st time in history actually work for nios2. Signed-off-by: Atle Nissestad --- linux-2.6.x/arch/nios2nommu/kernel/ptrace.c | 86 ++++++++++++++++----------- linux-2.6.x/include/asm-nios2nommu/ptrace.h | 38 ++++++++---- 2 files changed, 76 insertions(+), 48 deletions(-) diff --git a/linux-2.6.x/arch/nios2nommu/kernel/ptrace.c b/linux-2.6.x/arch/nios2nommu/kernel/ptrace.c index 59940aa..d2028b7 100644 --- a/linux-2.6.x/arch/nios2nommu/kernel/ptrace.c +++ b/linux-2.6.x/arch/nios2nommu/kernel/ptrace.c @@ -25,6 +25,14 @@ #include #include +#define DEBUG + +#ifdef DEBUG +# define PRINTK_DEBUG(str...) printk(KERN_DEBUG str) +#else +# define PRINTK_DEBUG(str...) do { } while (0) +#endif + /* * does not yet catch signals sent when the child dies. * in exit.c or in signal.c. @@ -38,18 +46,21 @@ #define PT_REG(reg) ((long)&((struct pt_regs *)0)->reg) #define SW_REG(reg) ((long)&((struct switch_stack *)0)->reg \ - sizeof(struct switch_stack)) + /* Mapping from PT_xxx to the stack offset at which the register is saved. Notice that usp has no stack-slot and needs to be treated specially (see get_reg/put_reg below). */ static int regoff[] = { - -1, PT_REG(r1), PT_REG(r2), PT_REG(r3), PT_REG(r4), - PT_REG(r5), PT_REG(r6), PT_REG(r7), PT_REG(r8), - PT_REG(r9), PT_REG(r10), PT_REG(r11), PT_REG(r12), - PT_REG(r13), PT_REG(r14), PT_REG(r15), SW_REG(r16), - SW_REG(r17), SW_REG(r18), SW_REG(r19), SW_REG(r20), - SW_REG(r21), SW_REG(r22), SW_REG(r23), -1, -1, - PT_REG(gp), PT_REG(sp), -1, -1, PT_REG(ra), -1, - PT_REG(estatus), -1, -1, -1 + -1, PT_REG( r1), PT_REG( r2), PT_REG( r3), + PT_REG( r4), PT_REG( r5), PT_REG( r6), PT_REG( r7), + PT_REG( r8), PT_REG( r9), PT_REG(r10), PT_REG(r11), + PT_REG(r12), PT_REG(r13), PT_REG(r14), PT_REG(r15), + SW_REG(r16), SW_REG(r17), SW_REG(r18), SW_REG(r19), + SW_REG(r20), SW_REG(r21), SW_REG(r22), SW_REG(r23), + -1, -1, PT_REG( gp), PT_REG( sp), + -1, -1, -1, PT_REG( ra), + -1, PT_REG(estatus), -1, -1, + -1, -1 }; /* @@ -59,15 +70,7 @@ static inline long get_reg(struct task_struct *task, int regno) { unsigned long *addr; - if (regno == PTR_R0) - return 0; - else if (regno == PTR_BA) - return 0; - else if (regno == PTR_STATUS) - return 0; - else if (regno == PTR_IENABLE) - return 0; - else if (regno == PTR_IPENDING) + if (regoff[regno] == -1) return 0; else if (regno < sizeof(regoff)/sizeof(regoff[0])) addr = (unsigned long *)(task->thread.kregs + regoff[regno]); @@ -84,15 +87,7 @@ static inline int put_reg(struct task_struct *task, int regno, { unsigned long *addr; - if (regno == PTR_R0) - return -1; - else if (regno == PTR_BA) - return -1; - else if (regno == PTR_STATUS) - return -1; - else if (regno == PTR_IENABLE) - return -1; - else if (regno == PTR_IPENDING) + if (regoff[regno] == -1) return -1; else if (regno < sizeof(regoff)/sizeof(regoff[0])) addr = (unsigned long *) (task->thread.kregs + regoff[regno]); @@ -122,11 +117,13 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) unsigned long tmp; int copied; + PRINTK_DEBUG("%s PEEKTEXT: addr=0x%08x\n", __FUNCTION__,(u32)addr); copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0); ret = -EIO; if (copied != sizeof(tmp)) break; ret = put_user(tmp,(unsigned long *) data); + PRINTK_DEBUG("%s PEEKTEXT: rword=0x%08x\n", __FUNCTION__, (u32)tmp); break; } @@ -139,33 +136,42 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) addr > sizeof(struct user) - 3) break; + PRINTK_DEBUG("%s PEEKUSR: addr=0x%08x\n", __FUNCTION__, (u32)addr); tmp = 0; /* Default return condition */ addr = addr >> 2; /* temporary hack. */ ret = -EIO; - if (addr < 19) { + if (addr < sizeof(regoff)/sizeof(regoff[0])) { tmp = get_reg(child, addr); - } else if (addr == 49) { + } else if (addr == PT_TEXT_ADDR/4) { tmp = child->mm->start_code; - } else if (addr == 50) { + } else if (addr == PT_DATA_ADDR/4) { tmp = child->mm->start_data; - } else if (addr == 51) { + } else if (addr == PT_TEXT_END_ADDR/4) { tmp = child->mm->end_code; } else break; ret = put_user(tmp,(unsigned long *) data); + PRINTK_DEBUG("%s PEEKUSR: rdword=0x%08x\n", __FUNCTION__, (u32)tmp); break; } /* when I and D space are separate, this will have to be fixed. */ case PTRACE_POKETEXT: /* write the word at location addr. */ - case PTRACE_POKEDATA: + case PTRACE_POKEDATA: { + int copied; + + PRINTK_DEBUG("%s POKETEXT: addr=0x%08x, data=0x%08x\n", __FUNCTION__, (u32)addr, (u32)data); ret = 0; - if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data)) + copied = access_process_vm(child, addr, &data, sizeof(data), 1); + PRINTK_DEBUG("%s POKETEXT: copied size = %d\n", __FUNCTION__, copied); + if (copied == sizeof(data)) break; ret = -EIO; break; + } case PTRACE_POKEUSR: /* write the word at location addr in the USER area */ + PRINTK_DEBUG("%s POKEUSR: addr=0x%08x, data=0x%08x\n", __FUNCTION__, (u32)addr, (u32)data); ret = -EIO; if ((addr & 3) || addr < 0 || addr > sizeof(struct user) - 3) @@ -177,7 +183,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) data &= SR_MASK; data |= get_reg(child, PTR_ESTATUS) & ~(SR_MASK); } - if (addr < 19) { + if (addr < sizeof(regoff)/sizeof(regoff[0])) { if (put_reg(child, addr, data)) break; ret = 0; @@ -188,6 +194,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */ case PTRACE_CONT: { /* restart after signal. */ + PRINTK_DEBUG("%s CONT: addr=0x%08x, data=0x%08x\n", __FUNCTION__, (u32)addr, (u32)data); ret = -EIO; if ((unsigned long) data > _NSIG) break; @@ -196,6 +203,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) else clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); child->exit_code = data; + PRINTK_DEBUG("%s CONT: About to run wake_up_process()\n", __FUNCTION__); wake_up_process(child); ret = 0; break; @@ -208,6 +216,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) */ case PTRACE_KILL: { + PRINTK_DEBUG("%s KILL\n", __FUNCTION__); ret = 0; if (child->state == EXIT_ZOMBIE) /* already dead */ break; @@ -224,6 +233,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) */ case PTRACE_SINGLESTEP: { /* set the trap flag. */ + PRINTK_DEBUG("%s SINGLESTEP: addr=0x%08x, data=0x%08x\n", __FUNCTION__, (u32)addr, (u32)data); ret = -EIO; if ((unsigned long) data > _NSIG) break; @@ -237,13 +247,16 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) } case PTRACE_DETACH: /* detach a process that was attached. */ + PRINTK_DEBUG("%s DETACH\n", __FUNCTION__); ret = ptrace_detach(child, data); break; case PTRACE_GETREGS: { /* Get all gp regs from the child. */ int i; unsigned long tmp; - for (i = 0; i < 19; i++) { + + PRINTK_DEBUG("%s GETREGS\n", __FUNCTION__); + for (i = 0; i < sizeof(regoff)/sizeof(regoff[0]); i++) { tmp = get_reg(child, i); if (put_user(tmp, (unsigned long *) data)) { ret = -EFAULT; @@ -258,7 +271,9 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) case PTRACE_SETREGS: { /* Set all gp regs in the child. */ int i; unsigned long tmp; - for (i = 0; i < 19; i++) { + + PRINTK_DEBUG("%s SETREGS\n", __FUNCTION__); + for (i = 0; i < sizeof(regoff)/sizeof(regoff[0]); i++) { if (get_user(tmp, (unsigned long *) data)) { ret = -EFAULT; break; @@ -275,6 +290,7 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) } default: + PRINTK_DEBUG("%s Undefined\n", __FUNCTION__); ret = -EIO; break; } diff --git a/linux-2.6.x/include/asm-nios2nommu/ptrace.h b/linux-2.6.x/include/asm-nios2nommu/ptrace.h index 924ad12..ceeed6b 100644 --- a/linux-2.6.x/include/asm-nios2nommu/ptrace.h +++ b/linux-2.6.x/include/asm-nios2nommu/ptrace.h @@ -26,6 +26,11 @@ #ifndef __ASSEMBLY__ +/* + * Register numbers used by 'ptrace' system call interface. + */ + +/* GP registers */ #define PTR_R0 0 #define PTR_R1 1 #define PTR_R2 2 @@ -58,11 +63,18 @@ #define PTR_EA 29 #define PTR_BA 30 #define PTR_RA 31 +/* Control registers */ #define PTR_STATUS 32 #define PTR_ESTATUS 33 #define PTR_BSTATUS 34 #define PTR_IENABLE 35 #define PTR_IPENDING 36 +#define PTR_CPUID 37 + +/* Text/data offsets, needed by gdbserver */ +#define PT_TEXT_ADDR 38*4 +#define PT_DATA_ADDR 39*4 +#define PT_TEXT_END_ADDR 40*4 /* this struct defines the way the registers are stored on the stack during a system call. @@ -70,7 +82,7 @@ There is a fake_regs in setup.c that has to match pt_regs.*/ struct pt_regs { - unsigned long r8; + unsigned long r8; /* r8-r15 Caller-saved GP registers */ unsigned long r9; unsigned long r10; unsigned long r11; @@ -78,21 +90,21 @@ struct pt_regs { unsigned long r13; unsigned long r14; unsigned long r15; - unsigned long r1; - unsigned long r2; - unsigned long r3; - unsigned long r4; + unsigned long r1; /* Assembler temporary */ + unsigned long r2; /* Retval LS 32bits */ + unsigned long r3; /* Retval MS 32bits */ + unsigned long r4; /* r4-r7 Register arguments */ unsigned long r5; unsigned long r6; unsigned long r7; - unsigned long orig_r2; - unsigned long ra; - unsigned long fp; - unsigned long sp; - unsigned long gp; + unsigned long orig_r2; /* Copy of r2 ?? */ + unsigned long ra; /* Return address */ + unsigned long fp; /* Frame pointer */ + unsigned long sp; /* Stack pointer */ + unsigned long gp; /* Global pointer */ unsigned long estatus; - unsigned long status_extension; - unsigned long ea; + unsigned long status_extension; /* Status extension. Used to fake user mode */ + unsigned long ea; /* Exception return address (pc) */ }; @@ -101,7 +113,7 @@ struct pt_regs { * switcher: it's pushed after the normal "struct pt_regs". */ struct switch_stack { - unsigned long r16; + unsigned long r16; /* r16-r23 Callee-saved GP registers */ unsigned long r17; unsigned long r18; unsigned long r19; -- 1.5.3.3