[deliverable/linux.git] / arch / arc / kernel / troubleshoot.c

/*
 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 */

#include <linux/ptrace.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/kdev_t.h>
#include <linux/fs_struct.h>
#include <linux/proc_fs.h>
#include <linux/file.h>
#include <asm/arcregs.h>

/*
 * Common routine to print scratch regs (r0-r12) or callee regs (r13-r25)
 *   -Prints 3 regs per line and a CR.
 *   -To continue, callee regs right after scratch, special handling of CR
 */
static noinline void print_reg_file(long *reg_rev, int start_num)
{
	unsigned int i;
	char buf[512];
	int n = 0, len = sizeof(buf);

	for (i = start_num; i < start_num + 13; i++) {
		n += scnprintf(buf + n, len - n, "r%02u: 0x%08lx\t",
			       i, (unsigned long)*reg_rev);

		if (((i + 1) % 3) == 0)
			n += scnprintf(buf + n, len - n, "\n");

		/* because pt_regs has regs reversed: r12..r0, r25..r13 */
		reg_rev--;
	}

	if (start_num != 0)
		n += scnprintf(buf + n, len - n, "\n\n");

	/* To continue printing callee regs on same line as scratch regs */
	if (start_num == 0)
		pr_info("%s", buf);
	else
		pr_cont("%s\n", buf);
}

static void show_callee_regs(struct callee_regs *cregs)
{
	print_reg_file(&(cregs->r13), 13);
}

void print_task_path_n_nm(struct task_struct *tsk, char *buf)
{
	struct path path;
	char *path_nm = NULL;
	struct mm_struct *mm;
	struct file *exe_file;

	mm = get_task_mm(tsk);
	if (!mm)
		goto done;

	exe_file = get_mm_exe_file(mm);
	mmput(mm);

	if (exe_file) {
		path = exe_file->f_path;
		path_get(&exe_file->f_path);
		fput(exe_file);
		path_nm = d_path(&path, buf, 255);
		path_put(&path);
	}

done:
	pr_info("Path: %s\n", path_nm);
}
EXPORT_SYMBOL(print_task_path_n_nm);

static void show_faulting_vma(unsigned long address, char *buf)
{
	struct vm_area_struct *vma;
	struct inode *inode;
	unsigned long ino = 0;
	dev_t dev = 0;
	char *nm = buf;

	/* can't use print_vma_addr() yet as it doesn't check for
	 * non-inclusive vma
	 */

	vma = find_vma(current->active_mm, address);

	/* check against the find_vma( ) behaviour which returns the next VMA
	 * if the container VMA is not found
	 */
	if (vma && (vma->vm_start <= address)) {
		struct file *file = vma->vm_file;
		if (file) {
			struct path *path = &file->f_path;
			nm = d_path(path, buf, PAGE_SIZE - 1);
			inode = vma->vm_file->f_path.dentry->d_inode;
			dev = inode->i_sb->s_dev;
			ino = inode->i_ino;
		}
		pr_info("    @off 0x%lx in [%s]\n"
			"    VMA: 0x%08lx to 0x%08lx\n",
			vma->vm_start < TASK_UNMAPPED_BASE ?
				address : address - vma->vm_start,
			nm, vma->vm_start, vma->vm_end);
	} else {
		pr_info("    @No matching VMA found\n");
	}
}

static void show_ecr_verbose(struct pt_regs *regs)
{
	unsigned int vec, cause_code, cause_reg;
	unsigned long address;

	cause_reg = current->thread.cause_code;
	pr_info("\n[ECR   ]: 0x%08x => ", cause_reg);

	/* For Data fault, this is data address not instruction addr */
	address = current->thread.fault_address;

	vec = cause_reg >> 16;
	cause_code = (cause_reg >> 8) & 0xFF;

	/* For DTLB Miss or ProtV, display the memory involved too */
	if (vec == ECR_V_DTLB_MISS) {
		pr_cont("Invalid %s @ 0x%08lx by insn @ 0x%08lx\n",
		       (cause_code == 0x01) ? "Read" :
		       ((cause_code == 0x02) ? "Write" : "EX"),
		       address, regs->ret);
	} else if (vec == ECR_V_ITLB_MISS) {
		pr_cont("Insn could not be fetched\n");
	} else if (vec == ECR_V_MACH_CHK) {
		pr_cont("%s\n", (cause_code == 0x0) ?
					"Double Fault" : "Other Fatal Err");

	} else if (vec == ECR_V_PROTV) {
		if (cause_code == ECR_C_PROTV_INST_FETCH)
			pr_cont("Execute from Non-exec Page\n");
		else if (cause_code == ECR_C_PROTV_MISALIG_DATA)
			pr_cont("Misaligned r/w from 0x%08lx\n", address);
		else
			pr_cont("%s access not allowed on page\n",
				(cause_code == 0x01) ? "Read" :
				((cause_code == 0x02) ? "Write" : "EX"));
	} else if (vec == ECR_V_INSN_ERR) {
		pr_cont("Illegal Insn\n");
	} else {
		pr_cont("Check Programmer's Manual\n");
	}
}

/************************************************************************
 *  API called by rest of kernel
 ***********************************************************************/

void show_regs(struct pt_regs *regs)
{
	struct task_struct *tsk = current;
	struct callee_regs *cregs;
	char *buf;

	buf = (char *)__get_free_page(GFP_TEMPORARY);
	if (!buf)
		return;

	print_task_path_n_nm(tsk, buf);
	show_regs_print_info(KERN_INFO);

	if (current->thread.cause_code)
		show_ecr_verbose(regs);

	pr_info("[EFA   ]: 0x%08lx\n[BLINK ]: %pS\n[ERET  ]: %pS\n",
		current->thread.fault_address,
		(void *)regs->blink, (void *)regs->ret);

	if (user_mode(regs))
		show_faulting_vma(regs->ret, buf); /* faulting code, not data */

	pr_info("[STAT32]: 0x%08lx", regs->status32);

#define STS_BIT(r, bit)	r->status32 & STATUS_##bit##_MASK ? #bit : ""
	if (!user_mode(regs))
		pr_cont(" : %2s %2s %2s %2s %2s\n",
			STS_BIT(regs, AE), STS_BIT(regs, A2), STS_BIT(regs, A1),
			STS_BIT(regs, E2), STS_BIT(regs, E1));

	pr_info("BTA: 0x%08lx\t SP: 0x%08lx\t FP: 0x%08lx\n",
		regs->bta, regs->sp, regs->fp);
	pr_info("LPS: 0x%08lx\tLPE: 0x%08lx\tLPC: 0x%08lx\n",
	       regs->lp_start, regs->lp_end, regs->lp_count);

	/* print regs->r0 thru regs->r12
	 * Sequential printing was generating horrible code
	 */
	print_reg_file(&(regs->r0), 0);

	/* If Callee regs were saved, display them too */
	cregs = (struct callee_regs *)current->thread.callee_reg;
	if (cregs)
		show_callee_regs(cregs);

	free_page((unsigned long)buf);
}

void show_kernel_fault_diag(const char *str, struct pt_regs *regs,
			    unsigned long address, unsigned long cause_reg)
{
	current->thread.fault_address = address;
	current->thread.cause_code = cause_reg;

	/* Caller and Callee regs */
	show_regs(regs);

	/* Show stack trace if this Fatality happened in kernel mode */
	if (!user_mode(regs))
		show_stacktrace(current, regs);
}

#ifdef CONFIG_DEBUG_FS

#include <linux/module.h>
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/pagemap.h>
#include <linux/init.h>
#include <linux/namei.h>
#include <linux/debugfs.h>

static struct dentry *test_dentry;
static struct dentry *test_dir;
static struct dentry *test_u32_dentry;

static u32 clr_on_read = 1;

#ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT
u32 numitlb, numdtlb, num_pte_not_present;

static int fill_display_data(char *kbuf)
{
	size_t num = 0;
	num += sprintf(kbuf + num, "I-TLB Miss %x\n", numitlb);
	num += sprintf(kbuf + num, "D-TLB Miss %x\n", numdtlb);
	num += sprintf(kbuf + num, "PTE not present %x\n", num_pte_not_present);

	if (clr_on_read)
		numitlb = numdtlb = num_pte_not_present = 0;

	return num;
}

static int tlb_stats_open(struct inode *inode, struct file *file)
{
	file->private_data = (void *)__get_free_page(GFP_KERNEL);
	return 0;
}

/* called on user read(): display the couters */
static ssize_t tlb_stats_output(struct file *file,	/* file descriptor */
				char __user *user_buf,	/* user buffer */
				size_t len,		/* length of buffer */
				loff_t *offset)		/* offset in the file */
{
	size_t num;
	char *kbuf = (char *)file->private_data;

	/* All of the data can he shoved in one iteration */
	if (*offset != 0)
		return 0;

	num = fill_display_data(kbuf);

	/* simple_read_from_buffer() is helper for copy to user space
	   It copies up to @2 (num) bytes from kernel buffer @4 (kbuf) at offset
	   @3 (offset) into the user space address starting at @1 (user_buf).
	   @5 (len) is max size of user buffer
	 */
	return simple_read_from_buffer(user_buf, num, offset, kbuf, len);
}

/* called on user write : clears the counters */
static ssize_t tlb_stats_clear(struct file *file, const char __user *user_buf,
			       size_t length, loff_t *offset)
{
	numitlb = numdtlb = num_pte_not_present = 0;
	return length;
}

static int tlb_stats_close(struct inode *inode, struct file *file)
{
	free_page((unsigned long)(file->private_data));
	return 0;
}

static const struct file_operations tlb_stats_file_ops = {
	.read = tlb_stats_output,
	.write = tlb_stats_clear,
	.open = tlb_stats_open,
	.release = tlb_stats_close
};
#endif

static int __init arc_debugfs_init(void)
{
	test_dir = debugfs_create_dir("arc", NULL);

#ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT
	test_dentry = debugfs_create_file("tlb_stats", 0444, test_dir, NULL,
					  &tlb_stats_file_ops);
#endif

	test_u32_dentry =
	    debugfs_create_u32("clr_on_read", 0444, test_dir, &clr_on_read);

	return 0;
}

module_init(arc_debugfs_init);

static void __exit arc_debugfs_exit(void)
{
	debugfs_remove(test_u32_dentry);
	debugfs_remove(test_dentry);
	debugfs_remove(test_dir);
}
module_exit(arc_debugfs_exit);

#endif
Commit	Line	Data
c08098f2 VG	1	/*
	2	* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	*/
	7
	8	#include <linux/ptrace.h>
0ef88a54 VG	9	#include <linux/module.h>
	10	#include <linux/mm.h>
	11	#include <linux/fs.h>
	12	#include <linux/kdev_t.h>
	13	#include <linux/fs_struct.h>
	14	#include <linux/proc_fs.h>
	15	#include <linux/file.h>
	16	#include <asm/arcregs.h>
	17
	18	/*
	19	* Common routine to print scratch regs (r0-r12) or callee regs (r13-r25)
	20	* -Prints 3 regs per line and a CR.
	21	* -To continue, callee regs right after scratch, special handling of CR
	22	*/
	23	static noinline void print_reg_file(long *reg_rev, int start_num)
	24	{
	25	unsigned int i;
	26	char buf[512];
	27	int n = 0, len = sizeof(buf);
	28
0ef88a54 VG	29	for (i = start_num; i < start_num + 13; i++) {
	30	n += scnprintf(buf + n, len - n, "r%02u: 0x%08lx\t",
	31	i, (unsigned long)*reg_rev);
	32
	33	if (((i + 1) % 3) == 0)
	34	n += scnprintf(buf + n, len - n, "\n");
	35
bd3c8b11	36	/* because pt_regs has regs reversed: r12..r0, r25..r13 */
0ef88a54 VG	37	reg_rev--;
	38	}
	39
	40	if (start_num != 0)
	41	n += scnprintf(buf + n, len - n, "\n\n");
	42
bd3c8b11 VG	43	/* To continue printing callee regs on same line as scratch regs */
	44	if (start_num == 0)
	45	pr_info("%s", buf);
	46	else
	47	pr_cont("%s\n", buf);
0ef88a54 VG	48	}
	49
	50	static void show_callee_regs(struct callee_regs *cregs)
	51	{
	52	print_reg_file(&(cregs->r13), 13);
	53	}
	54
	55	void print_task_path_n_nm(struct task_struct tsk, char buf)
	56	{
	57	struct path path;
	58	char *path_nm = NULL;
	59	struct mm_struct *mm;
	60	struct file *exe_file;
	61
	62	mm = get_task_mm(tsk);
	63	if (!mm)
	64	goto done;
	65
	66	exe_file = get_mm_exe_file(mm);
	67	mmput(mm);
	68
	69	if (exe_file) {
	70	path = exe_file->f_path;
	71	path_get(&exe_file->f_path);
	72	fput(exe_file);
	73	path_nm = d_path(&path, buf, 255);
	74	path_put(&path);
	75	}
	76
	77	done:
681a90ff	78	pr_info("Path: %s\n", path_nm);
0ef88a54 VG	79	}
	80	EXPORT_SYMBOL(print_task_path_n_nm);
	81
	82	static void show_faulting_vma(unsigned long address, char *buf)
	83	{
	84	struct vm_area_struct *vma;
	85	struct inode *inode;
	86	unsigned long ino = 0;
	87	dev_t dev = 0;
	88	char *nm = buf;
	89
bd3c8b11 VG	90	/* can't use print_vma_addr() yet as it doesn't check for
	91	* non-inclusive vma
	92	*/
	93
0ef88a54 VG	94	vma = find_vma(current->active_mm, address);
	95
	96	/* check against the find_vma( ) behaviour which returns the next VMA
	97	* if the container VMA is not found
	98	*/
	99	if (vma && (vma->vm_start <= address)) {
	100	struct file *file = vma->vm_file;
	101	if (file) {
	102	struct path *path = &file->f_path;
	103	nm = d_path(path, buf, PAGE_SIZE - 1);
	104	inode = vma->vm_file->f_path.dentry->d_inode;
	105	dev = inode->i_sb->s_dev;
	106	ino = inode->i_ino;
	107	}
	108	pr_info(" @off 0x%lx in [%s]\n"
bd3c8b11 VG	109	" VMA: 0x%08lx to 0x%08lx\n",
	110	vma->vm_start < TASK_UNMAPPED_BASE ?
	111	address : address - vma->vm_start,
	112	nm, vma->vm_start, vma->vm_end);
	113	} else {
0ef88a54	114	pr_info(" @No matching VMA found\n");
bd3c8b11	115	}
0ef88a54 VG	116	}
	117
	118	static void show_ecr_verbose(struct pt_regs *regs)
	119	{
	120	unsigned int vec, cause_code, cause_reg;
	121	unsigned long address;
	122
	123	cause_reg = current->thread.cause_code;
bd3c8b11	124	pr_info("\n[ECR ]: 0x%08x => ", cause_reg);
0ef88a54 VG	125
	126	/* For Data fault, this is data address not instruction addr */
	127	address = current->thread.fault_address;
	128
	129	vec = cause_reg >> 16;
	130	cause_code = (cause_reg >> 8) & 0xFF;
	131
	132	/* For DTLB Miss or ProtV, display the memory involved too */
	133	if (vec == ECR_V_DTLB_MISS) {
65464152 VG	134	pr_cont("Invalid %s @ 0x%08lx by insn @ 0x%08lx\n",
	135	(cause_code == 0x01) ? "Read" :
	136	((cause_code == 0x02) ? "Write" : "EX"),
0ef88a54 VG	137	address, regs->ret);
	138	} else if (vec == ECR_V_ITLB_MISS) {
	139	pr_cont("Insn could not be fetched\n");
	140	} else if (vec == ECR_V_MACH_CHK) {
	141	pr_cont("%s\n", (cause_code == 0x0) ?
	142	"Double Fault" : "Other Fatal Err");
	143
	144	} else if (vec == ECR_V_PROTV) {
	145	if (cause_code == ECR_C_PROTV_INST_FETCH)
	146	pr_cont("Execute from Non-exec Page\n");
0ef88a54 VG	147	else if (cause_code == ECR_C_PROTV_MISALIG_DATA)
0ef88a54 VG	148	pr_cont("Misaligned r/w from 0x%08lx\n", address);
65464152 VG	149	else
	150	pr_cont("%s access not allowed on page\n",
	151	(cause_code == 0x01) ? "Read" :
	152	((cause_code == 0x02) ? "Write" : "EX"));
0ef88a54 VG	153	} else if (vec == ECR_V_INSN_ERR) {
	154	pr_cont("Illegal Insn\n");
	155	} else {
	156	pr_cont("Check Programmer's Manual\n");
	157	}
	158	}
	159
	160	/************************************************************************
	161	* API called by rest of kernel
	162	***********************************************************************/
c08098f2 VG	163
	164	void show_regs(struct pt_regs *regs)
	165	{
0ef88a54 VG	166	struct task_struct *tsk = current;
	167	struct callee_regs *cregs;
	168	char *buf;
	169
	170	buf = (char *)__get_free_page(GFP_TEMPORARY);
	171	if (!buf)
	172	return;
	173
	174	print_task_path_n_nm(tsk, buf);
a43cb95d	175	show_regs_print_info(KERN_INFO);
0ef88a54 VG	176
	177	if (current->thread.cause_code)
	178	show_ecr_verbose(regs);
	179
bd3c8b11 VG	180	pr_info("[EFA ]: 0x%08lx\n[BLINK ]: %pS\n[ERET ]: %pS\n",
	181	current->thread.fault_address,
	182	(void )regs->blink, (void )regs->ret);
0ef88a54	183
bd3c8b11 VG	184	if (user_mode(regs))
bd3c8b11 VG	185	show_faulting_vma(regs->ret, buf); /* faulting code, not data */
0ef88a54	186
bd3c8b11 VG	187	pr_info("[STAT32]: 0x%08lx", regs->status32);
	188
	189	#define STS_BIT(r, bit) r->status32 & STATUS_##bit##_MASK ? #bit : ""
	190	if (!user_mode(regs))
	191	pr_cont(" : %2s %2s %2s %2s %2s\n",
	192	STS_BIT(regs, AE), STS_BIT(regs, A2), STS_BIT(regs, A1),
	193	STS_BIT(regs, E2), STS_BIT(regs, E1));
0ef88a54	194
bd3c8b11 VG	195	pr_info("BTA: 0x%08lx\t SP: 0x%08lx\t FP: 0x%08lx\n",
bd3c8b11 VG	196	regs->bta, regs->sp, regs->fp);
0ef88a54 VG	197	pr_info("LPS: 0x%08lx\tLPE: 0x%08lx\tLPC: 0x%08lx\n",
	198	regs->lp_start, regs->lp_end, regs->lp_count);
	199
	200	/* print regs->r0 thru regs->r12
	201	* Sequential printing was generating horrible code
	202	*/
	203	print_reg_file(&(regs->r0), 0);
	204
	205	/* If Callee regs were saved, display them too */
	206	cregs = (struct callee_regs *)current->thread.callee_reg;
	207	if (cregs)
	208	show_callee_regs(cregs);
	209
	210	free_page((unsigned long)buf);
c08098f2 VG	211	}
	212
	213	void show_kernel_fault_diag(const char str, struct pt_regs regs,
	214	unsigned long address, unsigned long cause_reg)
	215	{
0ef88a54 VG	216	current->thread.fault_address = address;
	217	current->thread.cause_code = cause_reg;
	218
	219	/* Caller and Callee regs */
	220	show_regs(regs);
	221
	222	/* Show stack trace if this Fatality happened in kernel mode */
	223	if (!user_mode(regs))
	224	show_stacktrace(current, regs);
c08098f2	225	}
0ef88a54 VG	226
	227	#ifdef CONFIG_DEBUG_FS
	228
	229	#include <linux/module.h>
	230	#include <linux/fs.h>
	231	#include <linux/mount.h>
	232	#include <linux/pagemap.h>
	233	#include <linux/init.h>
	234	#include <linux/namei.h>
	235	#include <linux/debugfs.h>
	236
	237	static struct dentry *test_dentry;
	238	static struct dentry *test_dir;
	239	static struct dentry *test_u32_dentry;
	240
	241	static u32 clr_on_read = 1;
	242
	243	#ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT
	244	u32 numitlb, numdtlb, num_pte_not_present;
	245
	246	static int fill_display_data(char *kbuf)
	247	{
	248	size_t num = 0;
	249	num += sprintf(kbuf + num, "I-TLB Miss %x\n", numitlb);
	250	num += sprintf(kbuf + num, "D-TLB Miss %x\n", numdtlb);
	251	num += sprintf(kbuf + num, "PTE not present %x\n", num_pte_not_present);
	252
	253	if (clr_on_read)
	254	numitlb = numdtlb = num_pte_not_present = 0;
	255
	256	return num;
	257	}
	258
	259	static int tlb_stats_open(struct inode inode, struct file file)
	260	{
	261	file->private_data = (void *)__get_free_page(GFP_KERNEL);
	262	return 0;
	263	}
	264
	265	/* called on user read(): display the couters */
	266	static ssize_t tlb_stats_output(struct file file, / file descriptor */
	267	char __user user_buf, / user buffer */
	268	size_t len, /* length of buffer */
	269	loff_t offset) / offset in the file */
	270	{
	271	size_t num;
	272	char kbuf = (char )file->private_data;
	273
	274	/* All of the data can he shoved in one iteration */
	275	if (*offset != 0)
	276	return 0;
	277
	278	num = fill_display_data(kbuf);
	279
	280	/* simple_read_from_buffer() is helper for copy to user space
	281	It copies up to @2 (num) bytes from kernel buffer @4 (kbuf) at offset
	282	@3 (offset) into the user space address starting at @1 (user_buf).
	283	@5 (len) is max size of user buffer
	284	*/
	285	return simple_read_from_buffer(user_buf, num, offset, kbuf, len);
	286	}
	287
	288	/* called on user write : clears the counters */
	289	static ssize_t tlb_stats_clear(struct file file, const char __user user_buf,
290	size_t length, loff_t *offset)
291	{
292	numitlb = numdtlb = num_pte_not_present = 0;
293	return length;
294	}
295
296	static int tlb_stats_close(struct inode inode, struct file file)
297	{
298	free_page((unsigned long)(file->private_data));
299	return 0;
300	}
301
302	static const struct file_operations tlb_stats_file_ops = {
303	.read = tlb_stats_output,
304	.write = tlb_stats_clear,
305	.open = tlb_stats_open,
306	.release = tlb_stats_close
307	};
308	#endif
309
310	static int __init arc_debugfs_init(void)
311	{
312	test_dir = debugfs_create_dir("arc", NULL);
313
314	#ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT
315	test_dentry = debugfs_create_file("tlb_stats", 0444, test_dir, NULL,
316	&tlb_stats_file_ops);
317	#endif
318
319	test_u32_dentry =
320	debugfs_create_u32("clr_on_read", 0444, test_dir, &clr_on_read);
321
322	return 0;
323	}
324
325	module_init(arc_debugfs_init);
326
327	static void __exit arc_debugfs_exit(void)
328	{
329	debugfs_remove(test_u32_dentry);
330	debugfs_remove(test_dentry);
331	debugfs_remove(test_dir);
332	}
333	module_exit(arc_debugfs_exit);
334
335	#endif