| .. | .. |
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| 1 | +// SPDX-License-Identifier: GPL-2.0 |
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| 1 | 2 | /* |
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| 2 | 3 | * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) |
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| 3 | | - * Licensed under the GPL |
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| 4 | 4 | */ |
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| 5 | 5 | |
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| 6 | 6 | #include <linux/mm.h> |
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| 7 | 7 | #include <linux/module.h> |
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| 8 | 8 | #include <linux/sched/signal.h> |
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| 9 | 9 | |
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| 10 | | -#include <asm/pgtable.h> |
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| 11 | 10 | #include <asm/tlbflush.h> |
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| 12 | 11 | #include <as-layout.h> |
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| 13 | 12 | #include <mem_user.h> |
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| .. | .. |
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| 37 | 36 | } mprotect; |
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| 38 | 37 | } u; |
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| 39 | 38 | } ops[1]; |
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| 39 | + int userspace; |
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| 40 | 40 | int index; |
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| 41 | | - struct mm_id *id; |
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| 41 | + struct mm_struct *mm; |
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| 42 | 42 | void *data; |
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| 43 | 43 | int force; |
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| 44 | 44 | }; |
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| 45 | 45 | |
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| 46 | | -#define INIT_HVC(mm, force) \ |
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| 46 | +#define INIT_HVC(mm, force, userspace) \ |
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| 47 | 47 | ((struct host_vm_change) \ |
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| 48 | 48 | { .ops = { { .type = NONE } }, \ |
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| 49 | | - .id = &mm->context.id, \ |
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| 49 | + .mm = mm, \ |
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| 50 | 50 | .data = NULL, \ |
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| 51 | + .userspace = userspace, \ |
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| 51 | 52 | .index = 0, \ |
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| 52 | 53 | .force = force }) |
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| 53 | 54 | |
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| .. | .. |
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| 68 | 69 | op = &hvc->ops[i]; |
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| 69 | 70 | switch (op->type) { |
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| 70 | 71 | case MMAP: |
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| 71 | | - ret = map(hvc->id, op->u.mmap.addr, op->u.mmap.len, |
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| 72 | | - op->u.mmap.prot, op->u.mmap.fd, |
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| 73 | | - op->u.mmap.offset, finished, &hvc->data); |
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| 72 | + if (hvc->userspace) |
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| 73 | + ret = map(&hvc->mm->context.id, op->u.mmap.addr, |
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| 74 | + op->u.mmap.len, op->u.mmap.prot, |
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| 75 | + op->u.mmap.fd, |
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| 76 | + op->u.mmap.offset, finished, |
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| 77 | + &hvc->data); |
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| 78 | + else |
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| 79 | + map_memory(op->u.mmap.addr, op->u.mmap.offset, |
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| 80 | + op->u.mmap.len, 1, 1, 1); |
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| 74 | 81 | break; |
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| 75 | 82 | case MUNMAP: |
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| 76 | | - ret = unmap(hvc->id, op->u.munmap.addr, |
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| 77 | | - op->u.munmap.len, finished, &hvc->data); |
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| 83 | + if (hvc->userspace) |
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| 84 | + ret = unmap(&hvc->mm->context.id, |
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| 85 | + op->u.munmap.addr, |
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| 86 | + op->u.munmap.len, finished, |
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| 87 | + &hvc->data); |
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| 88 | + else |
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| 89 | + ret = os_unmap_memory( |
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| 90 | + (void *) op->u.munmap.addr, |
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| 91 | + op->u.munmap.len); |
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| 92 | + |
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| 78 | 93 | break; |
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| 79 | 94 | case MPROTECT: |
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| 80 | | - ret = protect(hvc->id, op->u.mprotect.addr, |
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| 81 | | - op->u.mprotect.len, op->u.mprotect.prot, |
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| 82 | | - finished, &hvc->data); |
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| 95 | + if (hvc->userspace) |
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| 96 | + ret = protect(&hvc->mm->context.id, |
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| 97 | + op->u.mprotect.addr, |
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| 98 | + op->u.mprotect.len, |
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| 99 | + op->u.mprotect.prot, |
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| 100 | + finished, &hvc->data); |
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| 101 | + else |
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| 102 | + ret = os_protect_memory( |
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| 103 | + (void *) op->u.mprotect.addr, |
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| 104 | + op->u.mprotect.len, |
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| 105 | + 1, 1, 1); |
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| 83 | 106 | break; |
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| 84 | 107 | default: |
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| 85 | 108 | printk(KERN_ERR "Unknown op type %d in do_ops\n", |
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| .. | .. |
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| 100 | 123 | { |
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| 101 | 124 | __u64 offset; |
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| 102 | 125 | struct host_vm_op *last; |
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| 103 | | - int fd, ret = 0; |
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| 126 | + int fd = -1, ret = 0; |
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| 104 | 127 | |
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| 105 | | - fd = phys_mapping(phys, &offset); |
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| 128 | + if (virt + len > STUB_START && virt < STUB_END) |
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| 129 | + return -EINVAL; |
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| 130 | + |
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| 131 | + if (hvc->userspace) |
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| 132 | + fd = phys_mapping(phys, &offset); |
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| 133 | + else |
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| 134 | + offset = phys; |
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| 106 | 135 | if (hvc->index != 0) { |
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| 107 | 136 | last = &hvc->ops[hvc->index - 1]; |
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| 108 | 137 | if ((last->type == MMAP) && |
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| .. | .. |
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| 136 | 165 | struct host_vm_op *last; |
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| 137 | 166 | int ret = 0; |
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| 138 | 167 | |
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| 139 | | - if ((addr >= STUB_START) && (addr < STUB_END)) |
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| 168 | + if (addr + len > STUB_START && addr < STUB_END) |
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| 140 | 169 | return -EINVAL; |
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| 141 | 170 | |
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| 142 | 171 | if (hvc->index != 0) { |
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| .. | .. |
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| 165 | 194 | { |
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| 166 | 195 | struct host_vm_op *last; |
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| 167 | 196 | int ret = 0; |
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| 197 | + |
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| 198 | + if (addr + len > STUB_START && addr < STUB_END) |
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| 199 | + return -EINVAL; |
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| 168 | 200 | |
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| 169 | 201 | if (hvc->index != 0) { |
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| 170 | 202 | last = &hvc->ops[hvc->index - 1]; |
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| .. | .. |
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| 215 | 247 | prot = ((r ? UM_PROT_READ : 0) | (w ? UM_PROT_WRITE : 0) | |
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| 216 | 248 | (x ? UM_PROT_EXEC : 0)); |
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| 217 | 249 | if (hvc->force || pte_newpage(*pte)) { |
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| 218 | | - if (pte_present(*pte)) |
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| 219 | | - ret = add_mmap(addr, pte_val(*pte) & PAGE_MASK, |
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| 220 | | - PAGE_SIZE, prot, hvc); |
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| 221 | | - else |
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| 250 | + if (pte_present(*pte)) { |
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| 251 | + if (pte_newpage(*pte)) |
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| 252 | + ret = add_mmap(addr, pte_val(*pte) & PAGE_MASK, |
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| 253 | + PAGE_SIZE, prot, hvc); |
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| 254 | + } else |
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| 222 | 255 | ret = add_munmap(addr, PAGE_SIZE, hvc); |
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| 223 | 256 | } else if (pte_newprot(*pte)) |
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| 224 | 257 | ret = add_mprotect(addr, PAGE_SIZE, prot, hvc); |
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| .. | .. |
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| 249 | 282 | return ret; |
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| 250 | 283 | } |
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| 251 | 284 | |
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| 252 | | -static inline int update_pud_range(pgd_t *pgd, unsigned long addr, |
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| 285 | +static inline int update_pud_range(p4d_t *p4d, unsigned long addr, |
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| 253 | 286 | unsigned long end, |
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| 254 | 287 | struct host_vm_change *hvc) |
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| 255 | 288 | { |
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| .. | .. |
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| 257 | 290 | unsigned long next; |
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| 258 | 291 | int ret = 0; |
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| 259 | 292 | |
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| 260 | | - pud = pud_offset(pgd, addr); |
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| 293 | + pud = pud_offset(p4d, addr); |
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| 261 | 294 | do { |
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| 262 | 295 | next = pud_addr_end(addr, end); |
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| 263 | 296 | if (!pud_present(*pud)) { |
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| .. | .. |
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| 271 | 304 | return ret; |
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| 272 | 305 | } |
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| 273 | 306 | |
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| 307 | +static inline int update_p4d_range(pgd_t *pgd, unsigned long addr, |
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| 308 | + unsigned long end, |
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| 309 | + struct host_vm_change *hvc) |
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| 310 | +{ |
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| 311 | + p4d_t *p4d; |
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| 312 | + unsigned long next; |
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| 313 | + int ret = 0; |
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| 314 | + |
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| 315 | + p4d = p4d_offset(pgd, addr); |
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| 316 | + do { |
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| 317 | + next = p4d_addr_end(addr, end); |
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| 318 | + if (!p4d_present(*p4d)) { |
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| 319 | + if (hvc->force || p4d_newpage(*p4d)) { |
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| 320 | + ret = add_munmap(addr, next - addr, hvc); |
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| 321 | + p4d_mkuptodate(*p4d); |
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| 322 | + } |
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| 323 | + } else |
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| 324 | + ret = update_pud_range(p4d, addr, next, hvc); |
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| 325 | + } while (p4d++, addr = next, ((addr < end) && !ret)); |
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| 326 | + return ret; |
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| 327 | +} |
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| 328 | + |
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| 274 | 329 | void fix_range_common(struct mm_struct *mm, unsigned long start_addr, |
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| 275 | 330 | unsigned long end_addr, int force) |
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| 276 | 331 | { |
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| 277 | 332 | pgd_t *pgd; |
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| 278 | 333 | struct host_vm_change hvc; |
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| 279 | 334 | unsigned long addr = start_addr, next; |
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| 280 | | - int ret = 0; |
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| 335 | + int ret = 0, userspace = 1; |
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| 281 | 336 | |
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| 282 | | - hvc = INIT_HVC(mm, force); |
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| 337 | + hvc = INIT_HVC(mm, force, userspace); |
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| 283 | 338 | pgd = pgd_offset(mm, addr); |
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| 284 | 339 | do { |
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| 285 | 340 | next = pgd_addr_end(addr, end_addr); |
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| .. | .. |
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| 288 | 343 | ret = add_munmap(addr, next - addr, &hvc); |
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| 289 | 344 | pgd_mkuptodate(*pgd); |
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| 290 | 345 | } |
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| 291 | | - } |
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| 292 | | - else ret = update_pud_range(pgd, addr, next, &hvc); |
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| 346 | + } else |
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| 347 | + ret = update_p4d_range(pgd, addr, next, &hvc); |
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| 293 | 348 | } while (pgd++, addr = next, ((addr < end_addr) && !ret)); |
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| 294 | 349 | |
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| 295 | 350 | if (!ret) |
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| .. | .. |
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| 297 | 352 | |
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| 298 | 353 | /* This is not an else because ret is modified above */ |
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| 299 | 354 | if (ret) { |
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| 355 | + struct mm_id *mm_idp = ¤t->mm->context.id; |
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| 356 | + |
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| 300 | 357 | printk(KERN_ERR "fix_range_common: failed, killing current " |
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| 301 | 358 | "process: %d\n", task_tgid_vnr(current)); |
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| 302 | | - /* We are under mmap_sem, release it such that current can terminate */ |
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| 303 | | - up_write(¤t->mm->mmap_sem); |
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| 304 | | - force_sig(SIGKILL, current); |
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| 305 | | - do_signal(¤t->thread.regs); |
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| 359 | + mm_idp->kill = 1; |
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| 306 | 360 | } |
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| 307 | 361 | } |
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| 308 | 362 | |
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| .. | .. |
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| 310 | 364 | { |
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| 311 | 365 | struct mm_struct *mm; |
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| 312 | 366 | pgd_t *pgd; |
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| 367 | + p4d_t *p4d; |
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| 313 | 368 | pud_t *pud; |
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| 314 | 369 | pmd_t *pmd; |
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| 315 | 370 | pte_t *pte; |
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| 316 | 371 | unsigned long addr, last; |
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| 317 | | - int updated = 0, err; |
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| 372 | + int updated = 0, err = 0, force = 0, userspace = 0; |
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| 373 | + struct host_vm_change hvc; |
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| 318 | 374 | |
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| 319 | 375 | mm = &init_mm; |
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| 376 | + hvc = INIT_HVC(mm, force, userspace); |
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| 320 | 377 | for (addr = start; addr < end;) { |
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| 321 | 378 | pgd = pgd_offset(mm, addr); |
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| 322 | 379 | if (!pgd_present(*pgd)) { |
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| .. | .. |
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| 325 | 382 | last = end; |
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| 326 | 383 | if (pgd_newpage(*pgd)) { |
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| 327 | 384 | updated = 1; |
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| 328 | | - err = os_unmap_memory((void *) addr, |
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| 329 | | - last - addr); |
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| 385 | + err = add_munmap(addr, last - addr, &hvc); |
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| 330 | 386 | if (err < 0) |
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| 331 | 387 | panic("munmap failed, errno = %d\n", |
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| 332 | 388 | -err); |
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| .. | .. |
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| 335 | 391 | continue; |
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| 336 | 392 | } |
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| 337 | 393 | |
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| 338 | | - pud = pud_offset(pgd, addr); |
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| 394 | + p4d = p4d_offset(pgd, addr); |
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| 395 | + if (!p4d_present(*p4d)) { |
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| 396 | + last = ADD_ROUND(addr, P4D_SIZE); |
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| 397 | + if (last > end) |
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| 398 | + last = end; |
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| 399 | + if (p4d_newpage(*p4d)) { |
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| 400 | + updated = 1; |
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| 401 | + err = add_munmap(addr, last - addr, &hvc); |
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| 402 | + if (err < 0) |
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| 403 | + panic("munmap failed, errno = %d\n", |
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| 404 | + -err); |
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| 405 | + } |
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| 406 | + addr = last; |
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| 407 | + continue; |
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| 408 | + } |
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| 409 | + |
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| 410 | + pud = pud_offset(p4d, addr); |
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| 339 | 411 | if (!pud_present(*pud)) { |
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| 340 | 412 | last = ADD_ROUND(addr, PUD_SIZE); |
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| 341 | 413 | if (last > end) |
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| 342 | 414 | last = end; |
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| 343 | 415 | if (pud_newpage(*pud)) { |
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| 344 | 416 | updated = 1; |
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| 345 | | - err = os_unmap_memory((void *) addr, |
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| 346 | | - last - addr); |
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| 417 | + err = add_munmap(addr, last - addr, &hvc); |
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| 347 | 418 | if (err < 0) |
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| 348 | 419 | panic("munmap failed, errno = %d\n", |
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| 349 | 420 | -err); |
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| .. | .. |
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| 359 | 430 | last = end; |
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| 360 | 431 | if (pmd_newpage(*pmd)) { |
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| 361 | 432 | updated = 1; |
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| 362 | | - err = os_unmap_memory((void *) addr, |
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| 363 | | - last - addr); |
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| 433 | + err = add_munmap(addr, last - addr, &hvc); |
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| 364 | 434 | if (err < 0) |
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| 365 | 435 | panic("munmap failed, errno = %d\n", |
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| 366 | 436 | -err); |
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| .. | .. |
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| 372 | 442 | pte = pte_offset_kernel(pmd, addr); |
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| 373 | 443 | if (!pte_present(*pte) || pte_newpage(*pte)) { |
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| 374 | 444 | updated = 1; |
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| 375 | | - err = os_unmap_memory((void *) addr, |
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| 376 | | - PAGE_SIZE); |
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| 445 | + err = add_munmap(addr, PAGE_SIZE, &hvc); |
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| 377 | 446 | if (err < 0) |
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| 378 | 447 | panic("munmap failed, errno = %d\n", |
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| 379 | 448 | -err); |
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| 380 | 449 | if (pte_present(*pte)) |
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| 381 | | - map_memory(addr, |
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| 382 | | - pte_val(*pte) & PAGE_MASK, |
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| 383 | | - PAGE_SIZE, 1, 1, 1); |
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| 450 | + err = add_mmap(addr, pte_val(*pte) & PAGE_MASK, |
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| 451 | + PAGE_SIZE, 0, &hvc); |
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| 384 | 452 | } |
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| 385 | 453 | else if (pte_newprot(*pte)) { |
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| 386 | 454 | updated = 1; |
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| 387 | | - os_protect_memory((void *) addr, PAGE_SIZE, 1, 1, 1); |
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| 455 | + err = add_mprotect(addr, PAGE_SIZE, 0, &hvc); |
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| 388 | 456 | } |
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| 389 | 457 | addr += PAGE_SIZE; |
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| 390 | 458 | } |
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| 459 | + if (!err) |
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| 460 | + err = do_ops(&hvc, hvc.index, 1); |
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| 461 | + |
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| 462 | + if (err < 0) |
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| 463 | + panic("flush_tlb_kernel failed, errno = %d\n", err); |
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| 391 | 464 | return updated; |
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| 392 | 465 | } |
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| 393 | 466 | |
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| 394 | 467 | void flush_tlb_page(struct vm_area_struct *vma, unsigned long address) |
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| 395 | 468 | { |
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| 396 | 469 | pgd_t *pgd; |
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| 470 | + p4d_t *p4d; |
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| 397 | 471 | pud_t *pud; |
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| 398 | 472 | pmd_t *pmd; |
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| 399 | 473 | pte_t *pte; |
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| .. | .. |
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| 403 | 477 | struct mm_id *mm_id; |
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| 404 | 478 | |
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| 405 | 479 | address &= PAGE_MASK; |
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| 480 | + |
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| 481 | + if (address >= STUB_START && address < STUB_END) |
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| 482 | + goto kill; |
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| 483 | + |
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| 406 | 484 | pgd = pgd_offset(mm, address); |
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| 407 | 485 | if (!pgd_present(*pgd)) |
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| 408 | 486 | goto kill; |
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| 409 | 487 | |
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| 410 | | - pud = pud_offset(pgd, address); |
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| 488 | + p4d = p4d_offset(pgd, address); |
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| 489 | + if (!p4d_present(*p4d)) |
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| 490 | + goto kill; |
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| 491 | + |
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| 492 | + pud = pud_offset(p4d, address); |
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| 411 | 493 | if (!pud_present(*pud)) |
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| 412 | 494 | goto kill; |
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| 413 | 495 | |
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| .. | .. |
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| 457 | 539 | |
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| 458 | 540 | kill: |
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| 459 | 541 | printk(KERN_ERR "Failed to flush page for address 0x%lx\n", address); |
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| 460 | | - force_sig(SIGKILL, current); |
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| 461 | | -} |
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| 462 | | - |
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| 463 | | -pgd_t *pgd_offset_proc(struct mm_struct *mm, unsigned long address) |
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| 464 | | -{ |
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| 465 | | - return pgd_offset(mm, address); |
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| 466 | | -} |
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| 467 | | - |
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| 468 | | -pud_t *pud_offset_proc(pgd_t *pgd, unsigned long address) |
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| 469 | | -{ |
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| 470 | | - return pud_offset(pgd, address); |
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| 471 | | -} |
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| 472 | | - |
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| 473 | | -pmd_t *pmd_offset_proc(pud_t *pud, unsigned long address) |
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| 474 | | -{ |
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| 475 | | - return pmd_offset(pud, address); |
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| 476 | | -} |
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| 477 | | - |
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| 478 | | -pte_t *pte_offset_proc(pmd_t *pmd, unsigned long address) |
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| 479 | | -{ |
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| 480 | | - return pte_offset_kernel(pmd, address); |
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| 481 | | -} |
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| 482 | | - |
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| 483 | | -pte_t *addr_pte(struct task_struct *task, unsigned long addr) |
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| 484 | | -{ |
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| 485 | | - pgd_t *pgd = pgd_offset(task->mm, addr); |
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| 486 | | - pud_t *pud = pud_offset(pgd, addr); |
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| 487 | | - pmd_t *pmd = pmd_offset(pud, addr); |
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| 488 | | - |
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| 489 | | - return pte_offset_map(pmd, addr); |
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| 542 | + force_sig(SIGKILL); |
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| 490 | 543 | } |
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| 491 | 544 | |
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| 492 | 545 | void flush_tlb_all(void) |
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| 493 | 546 | { |
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| 547 | + /* |
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| 548 | + * Don't bother flushing if this address space is about to be |
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| 549 | + * destroyed. |
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| 550 | + */ |
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| 551 | + if (atomic_read(¤t->mm->mm_users) == 0) |
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| 552 | + return; |
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| 553 | + |
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| 494 | 554 | flush_tlb_mm(current->mm); |
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| 495 | 555 | } |
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| 496 | 556 | |
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| .. | .. |
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| 512 | 572 | static void fix_range(struct mm_struct *mm, unsigned long start_addr, |
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| 513 | 573 | unsigned long end_addr, int force) |
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| 514 | 574 | { |
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| 575 | + /* |
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| 576 | + * Don't bother flushing if this address space is about to be |
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| 577 | + * destroyed. |
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| 578 | + */ |
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| 579 | + if (atomic_read(&mm->mm_users) == 0) |
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| 580 | + return; |
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| 581 | + |
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| 515 | 582 | fix_range_common(mm, start_addr, end_addr, force); |
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| 516 | 583 | } |
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| 517 | 584 | |
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| .. | .. |
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| 527 | 594 | void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start, |
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| 528 | 595 | unsigned long end) |
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| 529 | 596 | { |
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| 530 | | - /* |
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| 531 | | - * Don't bother flushing if this address space is about to be |
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| 532 | | - * destroyed. |
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| 533 | | - */ |
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| 534 | | - if (atomic_read(&mm->mm_users) == 0) |
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| 535 | | - return; |
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| 536 | | - |
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| 537 | 597 | fix_range(mm, start, end, 0); |
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| 538 | 598 | } |
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| 539 | 599 | |
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