WebSVN – HelenOS – Diff – /branches/dynload/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/mm/page_fault.h>
#include <mm/as.h>
#include <genarch/mm/page_pt.h>
#include <arch.h>
#include <interrupt.h>
#include <print.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, %[dummy], c5, c0, 0"
        : [dummy] "=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, %[ret], c6, c0, 0"
        : [ret] "=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 does not 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 __attribute__ ((unused)) =
        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);
        printf("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.");
    }
}
 
/** 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) {
        printf("prefetch_abort\n");
        print_istate(istate);
        panic("page fault - prefetch_abort at address: %x.",
            istate->pc);
    }
}
 
/** @}
 */
 

Rev 4345	Rev 4346
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>	-
38	#include <arch/mm/page_fault.h>	37	#include <arch/mm/page_fault.h>
39	#include <mm/as.h>	38	#include <mm/as.h>
40	#include <genarch/mm/page_pt.h>	39	#include <genarch/mm/page_pt.h>
41	#include <arch.h>	40	#include <arch.h>
42	#include <interrupt.h>	41	#include <interrupt.h>
43	#include <print.h>	42	#include <print.h>
44		43
45	/** Returns value stored in fault status register.	44	/** Returns value stored in fault status register.
46	*	45	*
47	* @return Value stored in CP15 fault status register (FSR).	46	* @return Value stored in CP15 fault status register (FSR).
48	*/	47	*/
49	static inline fault_status_t read_fault_status_register(void)	48	static inline fault_status_t read_fault_status_register(void)
50	{	49	{
51	fault_status_union_t fsu;	50	fault_status_union_t fsu;
52		51
53	/* fault status is stored in CP15 register 5 */	52	/* fault status is stored in CP15 register 5 */
54	asm volatile (	53	asm volatile (
55	"mrc p15, 0, %[dummy], c5, c0, 0"	54	"mrc p15, 0, %[dummy], c5, c0, 0"
56	: [dummy] "=r" (fsu.dummy)	55	: [dummy] "=r" (fsu.dummy)
57	);	56	);
58		57
59	return fsu.fs;	58	return fsu.fs;
60	}	59	}
61		60
62	/** Returns FAR (fault address register) content.	61	/** Returns FAR (fault address register) content.
63	*	62	*
64	* @return FAR (fault address register) content (address that caused a page	63	* @return FAR (fault address register) content (address that caused a page
65	* fault)	64	* fault)
66	*/	65	*/
67	static inline uintptr_t read_fault_address_register(void)	66	static inline uintptr_t read_fault_address_register(void)
68	{	67	{
69	uintptr_t ret;	68	uintptr_t ret;
70		69
71	/* fault adress is stored in CP15 register 6 */	70	/* fault adress is stored in CP15 register 6 */
72	asm volatile (	71	asm volatile (
73	"mrc p15, 0, %[ret], c6, c0, 0"	72	"mrc p15, 0, %[ret], c6, c0, 0"
74	: [ret] "=r" (ret)	73	: [ret] "=r" (ret)
75	);	74	);
76		75
77	return ret;	76	return ret;
78	}	77	}
79		78
80	/** Decides whether the instruction is load/store or not.	79	/** Decides whether the instruction is load/store or not.
81	*	80	*
82	* @param instr Instruction	81	* @param instr Instruction
83	*	82	*
84	* @return true when instruction is load/store, false otherwise	83	* @return true when instruction is load/store, false otherwise
85	*	84	*
86	*/	85	*/
87	static inline bool is_load_store_instruction(instruction_t instr)	86	static inline bool is_load_store_instruction(instruction_t instr)
88	{	87	{
89	/* load store immediate offset */	88	/* load store immediate offset */
90	if (instr.type == 0x2)	89	if (instr.type == 0x2)
91	return true;	90	return true;
92		91
93	/* load store register offset */	92	/* load store register offset */
94	if ((instr.type == 0x3) && (instr.bit4 == 0))	93	if ((instr.type == 0x3) && (instr.bit4 == 0))
95	return true;	94	return true;
96		95
97	/* load store multiple */	96	/* load store multiple */
98	if (instr.type == 0x4)	97	if (instr.type == 0x4)
99	return true;	98	return true;
100		99
101	/* oprocessor load/store */	100	/* oprocessor load/store */
102	if (instr.type == 0x6)	101	if (instr.type == 0x6)
103	return true;	102	return true;
104		103
105	return false;	104	return false;
106	}	105	}
107		106
108	/** Decides whether the instruction is swap or not.	107	/** Decides whether the instruction is swap or not.
109	*	108	*
110	* @param instr Instruction	109	* @param instr Instruction
111	*	110	*
112	* @return true when instruction is swap, false otherwise	111	* @return true when instruction is swap, false otherwise
113	*/	112	*/
114	static inline bool is_swap_instruction(instruction_t instr)	113	static inline bool is_swap_instruction(instruction_t instr)
115	{	114	{
116	/* swap, swapb instruction */	115	/* swap, swapb instruction */
117	if ((instr.type == 0x0) &&	116	if ((instr.type == 0x0) &&
118	((instr.opcode == 0x8) \|\| (instr.opcode == 0xa)) &&	117	((instr.opcode == 0x8) \|\| (instr.opcode == 0xa)) &&
119	(instr.access == 0x0) && (instr.bits567 == 0x4) && (instr.bit4 == 1))	118	(instr.access == 0x0) && (instr.bits567 == 0x4) && (instr.bit4 == 1))
120	return true;	119	return true;
121		120
122	return false;	121	return false;
123	}	122	}
124		123
125	/** Decides whether read or write into memory is requested.	124	/** Decides whether read or write into memory is requested.
126	*	125	*
127	* @param instr_addr Address of instruction which tries to access memory.	126	* @param instr_addr Address of instruction which tries to access memory.
128	* @param badvaddr Virtual address the instruction tries to access.	127	* @param badvaddr Virtual address the instruction tries to access.
129	*	128	*
130	* @return Type of access into memory, PF_ACCESS_EXEC if no memory access is	129	* @return Type of access into memory, PF_ACCESS_EXEC if no memory access is
131	* requested.	130	* requested.
132	*/	131	*/
133	static pf_access_t get_memory_access_type(uint32_t instr_addr,	132	static pf_access_t get_memory_access_type(uint32_t instr_addr,
134	uintptr_t badvaddr)	133	uintptr_t badvaddr)
135	{	134	{
136	instruction_union_t instr_union;	135	instruction_union_t instr_union;
137	instr_union.pc = instr_addr;	136	instr_union.pc = instr_addr;
138		137
139	instruction_t instr = *(instr_union.instr);	138	instruction_t instr = *(instr_union.instr);
140		139
141	/* undefined instructions */	140	/* undefined instructions */
142	if (instr.condition == 0xf) {	141	if (instr.condition == 0xf) {
143	panic("page_fault - instruction does not access memory "	142	panic("page_fault - instruction does not access memory "
144	"(instr_code: %x, badvaddr:%x).", instr, badvaddr);	143	"(instr_code: %x, badvaddr:%x).", instr, badvaddr);
145	return PF_ACCESS_EXEC;	144	return PF_ACCESS_EXEC;
146	}	145	}
147		146
148	/* load store instructions */	147	/* load store instructions */
149	if (is_load_store_instruction(instr)) {	148	if (is_load_store_instruction(instr)) {
150	if (instr.access == 1) {	149	if (instr.access == 1) {
151	return PF_ACCESS_READ;	150	return PF_ACCESS_READ;
152	} else {	151	} else {
153	return PF_ACCESS_WRITE;	152	return PF_ACCESS_WRITE;
154	}	153	}
155	}	154	}
156		155
157	/* swap, swpb instruction */	156	/* swap, swpb instruction */
158	if (is_swap_instruction(instr)) {	157	if (is_swap_instruction(instr)) {
159	return PF_ACCESS_WRITE;	158	return PF_ACCESS_WRITE;
160	}	159	}
161		160
162	panic("page_fault - instruction doesn't access memory "	161	panic("page_fault - instruction doesn't access memory "
163	"(instr_code: %x, badvaddr:%x).", instr, badvaddr);	162	"(instr_code: %x, badvaddr:%x).", instr, badvaddr);
164		163
165	return PF_ACCESS_EXEC;	164	return PF_ACCESS_EXEC;
166	}	165	}
167		166
168	/** Handles "data abort" exception (load or store at invalid address).	167	/** Handles "data abort" exception (load or store at invalid address).
169	*	168	*
170	* @param exc_no Exception number.	169	* @param exc_no Exception number.
171	* @param istate CPU state when exception occured.	170	* @param istate CPU state when exception occured.
172	*/	171	*/
173	void data_abort(int exc_no, istate_t *istate)	172	void data_abort(int exc_no, istate_t *istate)
174	{	173	{
175	fault_status_t fsr __attribute__ ((unused)) =	174	fault_status_t fsr __attribute__ ((unused)) =
176	read_fault_status_register();	175	read_fault_status_register();
177	uintptr_t badvaddr = read_fault_address_register();	176	uintptr_t badvaddr = read_fault_address_register();
178		177
179	pf_access_t access = get_memory_access_type(istate->pc, badvaddr);	178	pf_access_t access = get_memory_access_type(istate->pc, badvaddr);
180		179
181	int ret = as_page_fault(badvaddr, access, istate);	180	int ret = as_page_fault(badvaddr, access, istate);
182		181
183	if (ret == AS_PF_FAULT) {	182	if (ret == AS_PF_FAULT) {
184	print_istate(istate);	183	print_istate(istate);
185	dprintf("page fault - pc: %x, va: %x, status: %x(%x), "	184	printf("page fault - pc: %x, va: %x, status: %x(%x), "
186	"access:%d\n", istate->pc, badvaddr, fsr.status, fsr,	185	"access:%d\n", istate->pc, badvaddr, fsr.status, fsr,
187	access);	186	access);
188		187
189	fault_if_from_uspace(istate, "Page fault: %#x.", badvaddr);	188	fault_if_from_uspace(istate, "Page fault: %#x.", badvaddr);
190	panic("Page fault.");	189	panic("Page fault.");
191	}	190	}
192	}	191	}
193		192
194	/** Handles "prefetch abort" exception (instruction couldn't be executed).	193	/** Handles "prefetch abort" exception (instruction couldn't be executed).
195	*	194	*
196	* @param exc_no Exception number.	195	* @param exc_no Exception number.
197	* @param istate CPU state when exception occured.	196	* @param istate CPU state when exception occured.
198	*/	197	*/
199	void prefetch_abort(int exc_no, istate_t *istate)	198	void prefetch_abort(int exc_no, istate_t *istate)
200	{	199	{
201	int ret = as_page_fault(istate->pc, PF_ACCESS_EXEC, istate);	200	int ret = as_page_fault(istate->pc, PF_ACCESS_EXEC, istate);
202		201
203	if (ret == AS_PF_FAULT) {	202	if (ret == AS_PF_FAULT) {
204	dprintf("prefetch_abort\n");	203	printf("prefetch_abort\n");
205	print_istate(istate);	204	print_istate(istate);
206	panic("page fault - prefetch_abort at address: %x.",	205	panic("page fault - prefetch_abort at address: %x.",
207	istate->pc);	206	istate->pc);
208	}	207	}
209	}	208	}
210		209
211	/** @}	210	/** @}
212	*/	211	*/
213		212

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(root)/branches/dynload/kernel/arch/arm32/src/mm/page_fault.c – Rev 4345 → 4346