[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;
	struct mm_struct *active_mm = current->active_mm;

	/* can't use print_vma_addr() yet as it doesn't check for
	 * non-inclusive vma
	 */
	down_read(&active_mm->mmap_sem);
	vma = find_vma(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 = file_inode(vma->vm_file);
			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");

	up_read(&active_mm->mmap_sem);
}

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

	pr_info("\n[ECR   ]: 0x%08lx => ", regs->event);

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

	vec = regs->ecr_vec;
	cause_code = regs->ecr_cause;

	/* 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);

	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)
{
	current->thread.fault_address = address;

	/* 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;
5040573e	89	struct mm_struct *active_mm = current->active_mm;
0ef88a54	90
bd3c8b11 VG	91	/* can't use print_vma_addr() yet as it doesn't check for
	92	* non-inclusive vma
	93	*/
5040573e DB	94	down_read(&active_mm->mmap_sem);
5040573e DB	95	vma = find_vma(active_mm, address);
0ef88a54 VG	96
	97	/* check against the find_vma( ) behaviour which returns the next VMA
	98	* if the container VMA is not found
	99	*/
	100	if (vma && (vma->vm_start <= address)) {
	101	struct file *file = vma->vm_file;
	102	if (file) {
	103	struct path *path = &file->f_path;
	104	nm = d_path(path, buf, PAGE_SIZE - 1);
e77e4300	105	inode = file_inode(vma->vm_file);
0ef88a54 VG	106	dev = inode->i_sb->s_dev;
	107	ino = inode->i_ino;
	108	}
	109	pr_info(" @off 0x%lx in [%s]\n"
bd3c8b11 VG	110	" VMA: 0x%08lx to 0x%08lx\n",
	111	vma->vm_start < TASK_UNMAPPED_BASE ?
	112	address : address - vma->vm_start,
	113	nm, vma->vm_start, vma->vm_end);
5040573e	114	} else
0ef88a54	115	pr_info(" @No matching VMA found\n");
5040573e DB	116
5040573e DB	117	up_read(&active_mm->mmap_sem);
0ef88a54 VG	118	}
	119
	120	static void show_ecr_verbose(struct pt_regs *regs)
	121	{
502a0c77	122	unsigned int vec, cause_code;
0ef88a54 VG	123	unsigned long address;
0ef88a54 VG	124
502a0c77	125	pr_info("\n[ECR ]: 0x%08lx => ", regs->event);
0ef88a54 VG	126
	127	/* For Data fault, this is data address not instruction addr */
	128	address = current->thread.fault_address;
	129
502a0c77 VG	130	vec = regs->ecr_vec;
502a0c77 VG	131	cause_code = regs->ecr_cause;
0ef88a54 VG	132
	133	/* For DTLB Miss or ProtV, display the memory involved too */
	134	if (vec == ECR_V_DTLB_MISS) {
65464152 VG	135	pr_cont("Invalid %s @ 0x%08lx by insn @ 0x%08lx\n",
	136	(cause_code == 0x01) ? "Read" :
	137	((cause_code == 0x02) ? "Write" : "EX"),
0ef88a54 VG	138	address, regs->ret);
	139	} else if (vec == ECR_V_ITLB_MISS) {
	140	pr_cont("Insn could not be fetched\n");
	141	} else if (vec == ECR_V_MACH_CHK) {
	142	pr_cont("%s\n", (cause_code == 0x0) ?
	143	"Double Fault" : "Other Fatal Err");
	144
	145	} else if (vec == ECR_V_PROTV) {
	146	if (cause_code == ECR_C_PROTV_INST_FETCH)
	147	pr_cont("Execute from Non-exec Page\n");
0ef88a54 VG	148	else if (cause_code == ECR_C_PROTV_MISALIG_DATA)
0ef88a54 VG	149	pr_cont("Misaligned r/w from 0x%08lx\n", address);
65464152 VG	150	else
	151	pr_cont("%s access not allowed on page\n",
	152	(cause_code == 0x01) ? "Read" :
	153	((cause_code == 0x02) ? "Write" : "EX"));
0ef88a54 VG	154	} else if (vec == ECR_V_INSN_ERR) {
	155	pr_cont("Illegal Insn\n");
	156	} else {
	157	pr_cont("Check Programmer's Manual\n");
	158	}
	159	}
	160
	161	/************************************************************************
	162	* API called by rest of kernel
	163	***********************************************************************/
c08098f2 VG	164
	165	void show_regs(struct pt_regs *regs)
	166	{
0ef88a54 VG	167	struct task_struct *tsk = current;
	168	struct callee_regs *cregs;
	169	char *buf;
	170
	171	buf = (char *)__get_free_page(GFP_TEMPORARY);
	172	if (!buf)
	173	return;
	174
	175	print_task_path_n_nm(tsk, buf);
a43cb95d	176	show_regs_print_info(KERN_INFO);
0ef88a54	177
502a0c77	178	show_ecr_verbose(regs);
0ef88a54	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,
38a9ff6d	214	unsigned long address)
c08098f2	215	{
0ef88a54	216	current->thread.fault_address = address;
0ef88a54 VG	217
	218	/* Caller and Callee regs */
	219	show_regs(regs);
	220
	221	/* Show stack trace if this Fatality happened in kernel mode */
	222	if (!user_mode(regs))
	223	show_stacktrace(current, regs);
c08098f2	224	}
0ef88a54 VG	225
	226	#ifdef CONFIG_DEBUG_FS
	227
	228	#include <linux/module.h>
	229	#include <linux/fs.h>
	230	#include <linux/mount.h>
	231	#include <linux/pagemap.h>
	232	#include <linux/init.h>
	233	#include <linux/namei.h>
	234	#include <linux/debugfs.h>
	235
	236	static struct dentry *test_dentry;
	237	static struct dentry *test_dir;
	238	static struct dentry *test_u32_dentry;
	239
	240	static u32 clr_on_read = 1;
	241
	242	#ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT
	243	u32 numitlb, numdtlb, num_pte_not_present;
	244
	245	static int fill_display_data(char *kbuf)
	246	{
	247	size_t num = 0;
	248	num += sprintf(kbuf + num, "I-TLB Miss %x\n", numitlb);
	249	num += sprintf(kbuf + num, "D-TLB Miss %x\n", numdtlb);
	250	num += sprintf(kbuf + num, "PTE not present %x\n", num_pte_not_present);
	251
	252	if (clr_on_read)
	253	numitlb = numdtlb = num_pte_not_present = 0;
	254
	255	return num;
	256	}
	257
	258	static int tlb_stats_open(struct inode inode, struct file file)
	259	{
	260	file->private_data = (void *)__get_free_page(GFP_KERNEL);
	261	return 0;
	262	}
	263
	264	/* called on user read(): display the couters */
	265	static ssize_t tlb_stats_output(struct file file, / file descriptor */
	266	char __user user_buf, / user buffer */
	267	size_t len, /* length of buffer */
	268	loff_t offset) / offset in the file */
	269	{
	270	size_t num;
	271	char kbuf = (char )file->private_data;
	272
	273	/* All of the data can he shoved in one iteration */
	274	if (*offset != 0)
	275	return 0;
	276
	277	num = fill_display_data(kbuf);
	278
	279	/* simple_read_from_buffer() is helper for copy to user space
	280	It copies up to @2 (num) bytes from kernel buffer @4 (kbuf) at offset
	281	@3 (offset) into the user space address starting at @1 (user_buf).
	282	@5 (len) is max size of user buffer
	283	*/
	284	return simple_read_from_buffer(user_buf, num, offset, kbuf, len);
	285	}
	286
	287	/* called on user write : clears the counters */
	288	static ssize_t tlb_stats_clear(struct file file, const char __user user_buf,
289	size_t length, loff_t *offset)
290	{
291	numitlb = numdtlb = num_pte_not_present = 0;
292	return length;
293	}
294
295	static int tlb_stats_close(struct inode inode, struct file file)
296	{
297	free_page((unsigned long)(file->private_data));
298	return 0;
299	}
300
301	static const struct file_operations tlb_stats_file_ops = {
302	.read = tlb_stats_output,
303	.write = tlb_stats_clear,
304	.open = tlb_stats_open,
305	.release = tlb_stats_close
306	};
307	#endif
308
309	static int __init arc_debugfs_init(void)
310	{
311	test_dir = debugfs_create_dir("arc", NULL);
312
313	#ifdef CONFIG_ARC_DBG_TLB_MISS_COUNT
314	test_dentry = debugfs_create_file("tlb_stats", 0444, test_dir, NULL,
315	&tlb_stats_file_ops);
316	#endif
317
318	test_u32_dentry =
319	debugfs_create_u32("clr_on_read", 0444, test_dir, &clr_on_read);
320
321	return 0;
322	}
323
324	module_init(arc_debugfs_init);
325
326	static void __exit arc_debugfs_exit(void)
327	{
328	debugfs_remove(test_u32_dentry);
329	debugfs_remove(test_dentry);
330	debugfs_remove(test_dir);
331	}
332	module_exit(arc_debugfs_exit);
333
334	#endif