Subversion Repositories HelenOS-historic

Rev

Rev 1270 | Rev 1374 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
1215 decky 1
/*
2
 * Copyright (C) 2006 Martin Decky
3
 * All rights reserved.
4
 *
5
 * Redistribution and use in source and binary forms, with or without
6
 * modification, are permitted provided that the following conditions
7
 * are met:
8
 *
9
 * - Redistributions of source code must retain the above copyright
10
 *   notice, this list of conditions and the following disclaimer.
11
 * - Redistributions in binary form must reproduce the above copyright
12
 *   notice, this list of conditions and the following disclaimer in the
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
15
 *   derived from this software without specific prior written permission.
16
 *
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
19
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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
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
26
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
 */
28
 
29
#include <arch/mm/tlb.h>
30
#include <arch/types.h>
31
#include <mm/tlb.h>
1269 decky 32
#include <mm/frame.h>
1215 decky 33
#include <mm/page.h>
34
#include <mm/as.h>
35
#include <arch.h>
36
#include <print.h>
37
#include <symtab.h>
38
 
39
 
1269 decky 40
static phte_t *phte;
41
 
42
 
1215 decky 43
/** Initialize Page Hash Table.
44
 *
45
 * Setup the Page Hash Table with no entries.
46
 *
47
 */
48
void tlb_arch_init(void)
49
{
1269 decky 50
    phte_t *physical_phte = (phte_t *) PFN2ADDR(frame_alloc(PHT_ORDER, FRAME_KA | FRAME_PANIC));
51
    phte =(phte_t *) PA2KA((__address) physical_phte);
52
 
53
    ASSERT((__address) physical_phte % (1 << PHT_BITS) == 0);
54
 
55
    memsetb((__address) phte, 1 << PHT_BITS, 0);
56
 
57
    asm volatile (
58
        "mtsdr1 %0\n"
59
        :
60
        : "r" ((__address) physical_phte)
61
    );
1215 decky 62
}
63
 
64
 
65
/** Try to find PTE for faulting address
66
 *
67
 * Try to find PTE for faulting address.
68
 * The AS->lock must be held on entry to this function.
69
 *
70
 * @param badvaddr Faulting virtual address.
1288 jermar 71
 * @param istate Pointer to interrupted state.
72
 * @param pfrc Pointer to variable where as_page_fault() return code will be stored.
1215 decky 73
 * @return         PTE on success, NULL otherwise.
74
 *
75
 */
1288 jermar 76
static pte_t *find_mapping_and_check(__address badvaddr, istate_t *istate, int *pfcr)
1215 decky 77
{
78
    /*
79
     * Check if the mapping exists in page tables.
80
     */
81
    pte_t *pte = page_mapping_find(AS, badvaddr);
82
    if ((pte) && (pte->p)) {
83
        /*
84
         * Mapping found in page tables.
85
         * Immediately succeed.
86
         */
87
        return pte;
88
    } else {
1288 jermar 89
        int rc;
90
 
1215 decky 91
        /*
92
         * Mapping not found in page tables.
93
         * Resort to higher-level page fault handler.
94
         */
95
        page_table_unlock(AS, true);
1288 jermar 96
        switch (rc = as_page_fault(badvaddr, istate)) {
97
        case AS_PF_OK:
1215 decky 98
            /*
99
             * The higher-level page fault handler succeeded,
100
             * The mapping ought to be in place.
101
             */
102
            page_table_lock(AS, true);
103
            pte = page_mapping_find(AS, badvaddr);
104
            ASSERT((pte) && (pte->p));
105
            return pte;
1288 jermar 106
            break;
107
        case AS_PF_DEFER:
1215 decky 108
            page_table_lock(AS, true);
1288 jermar 109
            *pfcr = rc;
110
            return NULL;
111
            break;
112
        case AS_PF_FAULT:
113
            page_table_lock(AS, true);
1215 decky 114
            printf("Page fault.\n");
1288 jermar 115
            *pfcr = rc;
1215 decky 116
            return NULL;
1288 jermar 117
            break;
118
        default:
119
            panic("unexpected rc (%d)\n", rc);
120
            break;
121
        }  
1215 decky 122
    }
123
}
124
 
125
 
126
static void pht_refill_fail(__address badvaddr, istate_t *istate)
127
{
128
    char *symbol = "";
129
    char *sym2 = "";
130
 
131
    char *s = get_symtab_entry(istate->pc);
132
    if (s)
133
        symbol = s;
134
    s = get_symtab_entry(istate->lr);
135
    if (s)
136
        sym2 = s;
1269 decky 137
    panic("%p: PHT Refill Exception at %p (%s<-%s)\n", badvaddr, istate->pc, symbol, sym2);
1215 decky 138
}
139
 
140
 
1269 decky 141
/** Process Instruction/Data Storage Interrupt
1215 decky 142
 *
1269 decky 143
 * @param data   True if Data Storage Interrupt.
1215 decky 144
 * @param istate Interrupted register context.
145
 *
146
 */
1269 decky 147
void pht_refill(bool data, istate_t *istate)
1215 decky 148
{
149
    asid_t asid;
150
    __address badvaddr;
151
    pte_t *pte;
1269 decky 152
    __u32 page;
153
    __u32 api;
154
    __u32 vsid;
155
    __u32 hash;
156
    __u32 i;
1288 jermar 157
    int pfcr;
1215 decky 158
 
1269 decky 159
    if (data) {
160
        asm volatile (
161
            "mfdar %0\n"
162
            : "=r" (badvaddr)
163
        );
164
    } else
165
        badvaddr = istate->pc;
166
 
1215 decky 167
    spinlock_lock(&AS->lock);
168
    asid = AS->asid;
169
    spinlock_unlock(&AS->lock);
170
 
171
    page_table_lock(AS, true);
172
 
1288 jermar 173
    pte = find_mapping_and_check(badvaddr, istate, &pfcr);
174
    if (!pte) {
175
        switch (pfcr) {
176
        case AS_PF_FAULT:
177
            goto fail;
178
            break;
179
        case AS_PF_DEFER:
180
            /*
181
             * The page fault came during copy_from_uspace()
182
             * or copy_to_uspace().
183
             */
184
            page_table_unlock(AS, true);
185
            return;
186
        default:
187
            panic("Unexpected pfrc (%d)\n", pfcr);
188
            break;
189
        }
190
    }
1215 decky 191
 
1269 decky 192
    /* Record access to PTE */
1215 decky 193
    pte->a = 1;
194
 
1270 decky 195
    page = (badvaddr >> 12) & 0xffff;
1269 decky 196
    api = (badvaddr >> 22) & 0x3f;
197
    asm volatile (
198
        "mfsrin %0, %1\n"
199
        : "=r" (vsid)
1270 decky 200
        : "r" (badvaddr)
1269 decky 201
    );
202
 
203
    /* Primary hash (xor) */
204
    hash = ((vsid ^ page) & 0x3ff) << 3;
205
 
206
    /* Find invalid PTE in PTEG */
207
    for (i = 0; i < 8; i++) {
208
        if (!phte[hash + i].v)
209
            break;
210
    }
211
 
212
    // TODO: Check access/change bits, secondary hash
213
 
214
    if (i == 8)
215
        i = page % 8;
216
 
217
    phte[hash + i].v = 1;
218
    phte[hash + i].vsid = vsid;
219
    phte[hash + i].h = 0;
220
    phte[hash + i].api = api;
221
    phte[hash + i].rpn = pte->pfn;
222
    phte[hash + i].r = 0;
223
    phte[hash + i].c = 0;
224
    phte[hash + i].pp = 2; // FIXME
225
 
1215 decky 226
    page_table_unlock(AS, true);
227
    return;
228
 
229
fail:
230
    page_table_unlock(AS, true);
231
    pht_refill_fail(badvaddr, istate);
232
}
233
 
234
 
235
/** Print contents of Page Hash Table. */
236
void tlb_print(void)
237
{
238
}