WebSVN – HelenOS – Diff – /trunk/kernel/arch/arm32/src/mm/page_fault.c


/*
 * Copyright (c) 2007 Pavel Jancik, Michal Kebrt
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
/** @addtogroup arm32mm
 * @{
 */
/** @file
 *  @brief Page fault related functions.
 */
#include <panic.h>
#include <arch/exception.h>
#include <arch/debug/print.h>
#include <arch/mm/page_fault.h>
#include <mm/as.h>
#include <genarch/mm/page_pt.h>
#include <arch.h>
#include <interrupt.h>
 
/** Returns value stored in fault status register.
 *
 *  @return Value stored in CP15 fault status register (FSR).
 */
static inline fault_status_t read_fault_status_register(void)
{
    fault_status_union_t fsu;
 
    /* fault status is stored in CP15 register 5 */
    asm volatile (
        "mrc p15, 0, %0, c5, c0, 0"
        : "=r"(fsu.dummy)
    );
    return fsu.fs;
}
 
/** Returns FAR (fault address register) content.
 *
 * @return FAR (fault address register) content (address that caused a page
 *     fault)
 */
static inline uintptr_t read_fault_address_register(void)
{
    uintptr_t ret;
 
    /* fault adress is stored in CP15 register 6 */
    asm volatile (
        "mrc p15, 0, %0, c6, c0, 0"
        : "=r"(ret)
    );
    return ret;
}
 
/** Decides whether the instruction is load/store or not.
 *
 * @param instr Instruction
 *
 * @return true when instruction is load/store, false otherwise
 */
static inline bool is_load_store_instruction(instruction_t instr)
{
    /* load store immediate offset */
    if (instr.type == 0x2) {
        return true;
    }
 
    /* load store register offset */
    if (instr.type == 0x3 && instr.bit4 == 0) {
        return true;
    }
 
    /* load store multiple */
    if (instr.type == 0x4) {
        return true;
    }
 
    /* oprocessor load/store */
    if (instr.type == 0x6) {
        return true;
    }
 
    return false;
}
 
/** Decides whether the instruction is swap or not.
 *
 * @param instr Instruction
 *
 * @return true when instruction is swap, false otherwise
 */
static inline bool is_swap_instruction(instruction_t instr)
{
    /* swap, swapb instruction */
    if (instr.type == 0x0 &&
        (instr.opcode == 0x8 || instr.opcode == 0xa) &&
        instr.access == 0x0 && instr.bits567 == 0x4 && instr.bit4 == 1) {
        return true;
    }
 
    return false;
}
 
/** Decides whether read or write into memory is requested.
 *
 * @param instr_addr   Address of instruction which tries to access memory.
 * @param badvaddr     Virtual address the instruction tries to access.
 *
 * @return Type of access into memory, PF_ACCESS_EXEC if no memory access is
 *     requested.
 */
static pf_access_t get_memory_access_type(uint32_t instr_addr,
    uintptr_t badvaddr)
{
    instruction_union_t instr_union;
    instr_union.pc = instr_addr;
 
    instruction_t instr = *(instr_union.instr);
 
    /* undefined instructions */
    if (instr.condition == 0xf) {
        panic("page_fault - instruction doesn't access memory "
            "(instr_code: %x, badvaddr:%x)", instr, badvaddr);
        return PF_ACCESS_EXEC;
    }
 
    /* load store instructions */
    if (is_load_store_instruction(instr)) {
        if (instr.access == 1) {
            return PF_ACCESS_READ;
        } else {
            return PF_ACCESS_WRITE;
        }
    }
 
    /* swap, swpb instruction */
    if (is_swap_instruction(instr)) {
        return PF_ACCESS_WRITE;
    }
 
    panic("page_fault - instruction doesn't access memory "
        "(instr_code: %x, badvaddr:%x)", instr, badvaddr);
 
    return PF_ACCESS_EXEC;
}
 
/** Handles "data abort" exception (load or store at invalid address).
 *
 * @param exc_no    Exception number.
 * @param istate    CPU state when exception occured.
 */
void data_abort(int exc_no, istate_t *istate)
{
    fault_status_t fsr = read_fault_status_register();
    uintptr_t badvaddr = read_fault_address_register();
 
    pf_access_t access = get_memory_access_type(istate->pc, badvaddr);
 
    int ret = as_page_fault(badvaddr, access, istate);
 
    if (ret == AS_PF_FAULT) {
        print_istate(istate);
        dprintf("page fault - pc: %x, va: %x, status: %x(%x), "
            "access:%d\n", istate->pc, badvaddr, fsr.status, fsr,
            access);
 
        fault_if_from_uspace(istate, "Page fault: %#x", badvaddr);
        panic("page fault\n");
    }
}
 
/** Handles "prefetch abort" exception (instruction couldn't be executed).
 *
 * @param exc_no    Exception number.
 * @param istate    CPU state when exception occured.
 */
void prefetch_abort(int exc_no, istate_t *istate)
{
    int ret = as_page_fault(istate->pc, PF_ACCESS_EXEC, istate);
 
    if (ret == AS_PF_FAULT) {
        dprintf("prefetch_abort\n");
        print_istate(istate);
        panic("page fault - prefetch_abort at address: %x\n",
            istate->pc);
    }
}
 
/** @}
 */
 

Rev 2464	Rev 2465
1	/*	1	/*
2	* Copyright (c) 2007 Pavel Jancik, Michal Kebrt	2	* Copyright (c) 2007 Pavel Jancik, Michal Kebrt
3	* All rights reserved.	3	* All rights reserved.
4	*	4	*
5	* Redistribution and use in source and binary forms, with or without	5	* Redistribution and use in source and binary forms, with or without
6	* modification, are permitted provided that the following conditions	6	* modification, are permitted provided that the following conditions
7	* are met:	7	* are met:
8	*	8	*
9	* - Redistributions of source code must retain the above copyright	9	* - Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.	10	* notice, this list of conditions and the following disclaimer.
11	* - Redistributions in binary form must reproduce the above copyright	11	* - Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the	12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.	13	* documentation and/or other materials provided with the distribution.
14	* - The name of the author may not be used to endorse or promote products	14	* - The name of the author may not be used to endorse or promote products
15	* derived from this software without specific prior written permission.	15	* derived from this software without specific prior written permission.
16	*	16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27	*/	27	*/
28		28
29	/** @addtogroup arm32mm	29	/** @addtogroup arm32mm
30	* @{	30	* @{
31	*/	31	*/
32	/** @file	32	/** @file
33	* @brief Page fault related functions.	33	* @brief Page fault related functions.
34	*/	34	*/
35	#include <panic.h>	35	#include <panic.h>
36	#include <arch/exception.h>	36	#include <arch/exception.h>
37	#include <arch/debug/print.h>	37	#include <arch/debug/print.h>
38	#include <arch/mm/page_fault.h>	38	#include <arch/mm/page_fault.h>
39	#include <mm/as.h>	39	#include <mm/as.h>
40	#include <genarch/mm/page_pt.h>	40	#include <genarch/mm/page_pt.h>
41	#include <arch.h>	41	#include <arch.h>
42	#include <interrupt.h>	42	#include <interrupt.h>
43		43
44	/** Returns value stored in fault status register.	44	/** Returns value stored in fault status register.
45	*	45	*
46	* @return Value stored in CP15 fault status register (FSR).	46	* @return Value stored in CP15 fault status register (FSR).
47	*/	47	*/
48	static inline fault_status_t read_fault_status_register(void)	48	static inline fault_status_t read_fault_status_register(void)
49	{	49	{
50	fault_status_union_t fsu;	50	fault_status_union_t fsu;
51		51
52	/* fault status is stored in CP15 register 5 */	52	/* fault status is stored in CP15 register 5 */
53	asm volatile (	53	asm volatile (
54	"mrc p15, 0, %0, c5, c0, 0"	54	"mrc p15, 0, %0, c5, c0, 0"
55	: "=r"(fsu.dummy)	55	: "=r"(fsu.dummy)
56	);	56	);
57	return fsu.fs;	57	return fsu.fs;
58	}	58	}
59		59
60	/** Returns FAR (fault address register) content.	60	/** Returns FAR (fault address register) content.
61	*	61	*
62	* @return FAR (fault address register) content (address that caused a page	62	* @return FAR (fault address register) content (address that caused a page
63	* fault)	63	* fault)
64	*/	64	*/
65	static inline uintptr_t read_fault_address_register(void)	65	static inline uintptr_t read_fault_address_register(void)
66	{	66	{
67	uintptr_t ret;	67	uintptr_t ret;
68		68
69	/* fault adress is stored in CP15 register 6 */	69	/* fault adress is stored in CP15 register 6 */
70	asm volatile (	70	asm volatile (
71	"mrc p15, 0, %0, c6, c0, 0"	71	"mrc p15, 0, %0, c6, c0, 0"
72	: "=r"(ret)	72	: "=r"(ret)
73	);	73	);
74	return ret;	74	return ret;
75	}	75	}
76		76
77	/** Decides whether the instruction is load/store or not.	77	/** Decides whether the instruction is load/store or not.
78	*	78	*
79	* @param instr Instruction	79	* @param instr Instruction
80	*	80	*
81	* @return true when instruction is load/store, false otherwise	81	* @return true when instruction is load/store, false otherwise
82	*/	82	*/
83	static inline bool is_load_store_instruction(instruction_t instr)	83	static inline bool is_load_store_instruction(instruction_t instr)
84	{	84	{
85	/* load store immediate offset */	85	/* load store immediate offset */
86	if (instr.type == 0x2) {	86	if (instr.type == 0x2) {
87	return true;	87	return true;
88	}	88	}
89		89
90	/* load store register offset */	90	/* load store register offset */
91	if (instr.type == 0x3 && instr.bit4 == 0) {	91	if (instr.type == 0x3 && instr.bit4 == 0) {
92	return true;	92	return true;
93	}	93	}
94		94
95	/* load store multiple */	95	/* load store multiple */
96	if (instr.type == 0x4) {	96	if (instr.type == 0x4) {
97	return true;	97	return true;
98	}	98	}
99		99
100	/* oprocessor load/store */	100	/* oprocessor load/store */
101	if (instr.type == 0x6) {	101	if (instr.type == 0x6) {
102	return true;	102	return true;
103	}	103	}
104		104
105	return false;	105	return false;
106	}	106	}
107		107
108	/** Decides whether the instruction is swap or not.	108	/** Decides whether the instruction is swap or not.
109	*	109	*
110	* @param instr Instruction	110	* @param instr Instruction
111	*	111	*
112	* @return true when instruction is swap, false otherwise	112	* @return true when instruction is swap, false otherwise
113	*/	113	*/
114	static inline bool is_swap_instruction(instruction_t instr)	114	static inline bool is_swap_instruction(instruction_t instr)
115	{	115	{
116	/* swap, swapb instruction */	116	/* swap, swapb instruction */
117	if (instr.type == 0x0 &&	117	if (instr.type == 0x0 &&
118	(instr.opcode == 0x8 \|\| instr.opcode == 0xa) &&	118	(instr.opcode == 0x8 \|\| instr.opcode == 0xa) &&
119	instr.access == 0x0 && instr.bits567 == 0x4 && instr.bit4 == 1) {	119	instr.access == 0x0 && instr.bits567 == 0x4 && instr.bit4 == 1) {
120	return true;	120	return true;
121	}	121	}
122		122
123	return false;	123	return false;
124	}	124	}
125		125
126	/** Decides whether read or write into memory is requested.	126	/** Decides whether read or write into memory is requested.
127	*	127	*
128	* @param instr_addr Address of instruction which tries to access memory.	128	* @param instr_addr Address of instruction which tries to access memory.
129	* @param badvaddr Virtual address the instruction tries to access.	129	* @param badvaddr Virtual address the instruction tries to access.
130	*	130	*
131	* @return Type of access into memory, PF_ACCESS_EXEC if no memory access is	131	* @return Type of access into memory, PF_ACCESS_EXEC if no memory access is
132	* requested.	132	* requested.
133	*/	133	*/
134	static pf_access_t get_memory_access_type(uint32_t instr_addr,	134	static pf_access_t get_memory_access_type(uint32_t instr_addr,
135	uintptr_t badvaddr)	135	uintptr_t badvaddr)
136	{	136	{
137	instruction_union_t instr_union;	137	instruction_union_t instr_union;
138	instr_union.pc = instr_addr;	138	instr_union.pc = instr_addr;
139		139
140	instruction_t instr = *(instr_union.instr);	140	instruction_t instr = *(instr_union.instr);
141		141
142	/* undefined instructions */	142	/* undefined instructions */
143	if (instr.condition == 0xf) {	143	if (instr.condition == 0xf) {
144	panic("page_fault - instruction doesn't access memory "	144	panic("page_fault - instruction doesn't access memory "
145	"(instr_code: %x, badvaddr:%x)", instr, badvaddr);	145	"(instr_code: %x, badvaddr:%x)", instr, badvaddr);
146	return PF_ACCESS_EXEC;	146	return PF_ACCESS_EXEC;
147	}	147	}
148		148
149	/* load store instructions */	149	/* load store instructions */
150	if (is_load_store_instruction(instr)) {	150	if (is_load_store_instruction(instr)) {
151	if (instr.access == 1) {	151	if (instr.access == 1) {
152	return PF_ACCESS_READ;	152	return PF_ACCESS_READ;
153	} else {	153	} else {
154	return PF_ACCESS_WRITE;	154	return PF_ACCESS_WRITE;
155	}	155	}
156	}	156	}
157		157
158	/* swap, swpb instruction */	158	/* swap, swpb instruction */
159	if (is_swap_instruction(instr)) {	159	if (is_swap_instruction(instr)) {
160	return PF_ACCESS_WRITE;	160	return PF_ACCESS_WRITE;
161	}	161	}
162		162
163	panic("page_fault - instruction doesn't access memory "	163	panic("page_fault - instruction doesn't access memory "
164	"(instr_code: %x, badvaddr:%x)", instr, badvaddr);	164	"(instr_code: %x, badvaddr:%x)", instr, badvaddr);
165		165
166	return PF_ACCESS_EXEC;	166	return PF_ACCESS_EXEC;
167	}	167	}
168		168
169	/** Handles "data abort" exception (load or store at invalid address).	169	/** Handles "data abort" exception (load or store at invalid address).
170	*	170	*
171	* @param exc_no Exception number.	171	* @param exc_no Exception number.
172	* @param istate CPU state when exception occured.	172	* @param istate CPU state when exception occured.
173	*/	173	*/
174	void data_abort(int exc_no, istate_t *istate)	174	void data_abort(int exc_no, istate_t *istate)
175	{	175	{
176	fault_status_t fsr = read_fault_status_register();	176	fault_status_t fsr = read_fault_status_register();
177	uintptr_t badvaddr = read_fault_address_register();	177	uintptr_t badvaddr = read_fault_address_register();
178		178
179	pf_access_t access = get_memory_access_type(istate->pc, badvaddr);	179	pf_access_t access = get_memory_access_type(istate->pc, badvaddr);
180		180
181	int ret = as_page_fault(badvaddr, access, istate);	181	int ret = as_page_fault(badvaddr, access, istate);
182		182
183	if (ret == AS_PF_FAULT) {	183	if (ret == AS_PF_FAULT) {
184	print_istate(istate);	184	print_istate(istate);
185	dprintf("page fault - pc: %x, va: %x, status: %x(%x), "	185	dprintf("page fault - pc: %x, va: %x, status: %x(%x), "
186	"access:%d\n", istate->pc, badvaddr, fsr.status, fsr,	186	"access:%d\n", istate->pc, badvaddr, fsr.status, fsr,
187	access);	187	access);
188		188
189	fault_if_from_uspace(istate, "Page fault: %#x", badvaddr);	189	fault_if_from_uspace(istate, "Page fault: %#x", badvaddr);
190	panic("page fault\n");	190	panic("page fault\n");
191	}	191	}
192	}	192	}
193		193
194	/** Handles "prefetch abort" exception (instruction couldn't be executed).	194	/** Handles "prefetch abort" exception (instruction couldn't be executed).
195	*	195	*
196	* @param exc_no Exception number.	196	* @param exc_no Exception number.
197	* @param istate CPU state when exception occured.	197	* @param istate CPU state when exception occured.
198	*/	198	*/
199	void prefetch_abort(int exc_no, istate_t *istate)	199	void prefetch_abort(int exc_no, istate_t *istate)
200	{	200	{
201	int ret = as_page_fault(istate->pc, PF_ACCESS_EXEC, istate);	201	int ret = as_page_fault(istate->pc, PF_ACCESS_EXEC, istate);
202		202
203	if (ret == AS_PF_FAULT) {	203	if (ret == AS_PF_FAULT) {
204	dprintf("prefetch_abort\n");	204	dprintf("prefetch_abort\n");
205	print_istate(istate);	205	print_istate(istate);
206	panic("page fault - prefetch_abort at address: %x\n",	206	panic("page fault - prefetch_abort at address: %x\n",
207	istate->pc);	207	istate->pc);
208	}	208	}
209	}	209	}
210		210
211	/** @}	211	/** @}
212	*/	212	*/
213		213

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(root)/trunk/kernel/arch/arm32/src/mm/page_fault.c – Rev 2464 → 2465