/* * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) * Licensed under the GPL */ #include <linux/mm.h> #include <linux/module.h> #include <linux/sched.h> #include <asm/pgtable.h> #include <asm/tlbflush.h> #include <as-layout.h> #include <mem_user.h> #include <os.h> #include <skas.h> #include <kern_util.h> struct host_vm_change { struct host_vm_op { enum { NONE, MMAP, MUNMAP, MPROTECT } type; union { struct { unsigned long addr; unsigned long len; unsigned int prot; int fd; __u64 offset; } mmap; struct { unsigned long addr; unsigned long len; } munmap; struct { unsigned long addr; unsigned long len; unsigned int prot; } mprotect; } u; } ops[1]; int index; struct mm_id *id; void *data; int force; }; #define INIT_HVC(mm, force) \ ((struct host_vm_change) \ { .ops = { { .type = NONE } }, \ .id = &mm->context.id, \ .data = NULL, \ .index = 0, \ .force = force }) static int do_ops(struct host_vm_change *hvc, int end, int finished) { struct host_vm_op *op; int i, ret = 0; for (i = 0; i < end && !ret; i++) { op = &hvc->ops[i]; switch (op->type) { case MMAP: ret = map(hvc->id, op->u.mmap.addr, op->u.mmap.len, op->u.mmap.prot, op->u.mmap.fd, op->u.mmap.offset, finished, &hvc->data); break; case MUNMAP: ret = unmap(hvc->id, op->u.munmap.addr, op->u.munmap.len, finished, &hvc->data); break; case MPROTECT: ret = protect(hvc->id, op->u.mprotect.addr, op->u.mprotect.len, op->u.mprotect.prot, finished, &hvc->data); break; default: printk(KERN_ERR "Unknown op type %d in do_ops\n", op->type); BUG(); break; } } return ret; } static int add_mmap(unsigned long virt, unsigned long phys, unsigned long len, unsigned int prot, struct host_vm_change *hvc) { __u64 offset; struct host_vm_op *last; int fd, ret = 0; fd = phys_mapping(phys, &offset); if (hvc->index != 0) { last = &hvc->ops[hvc->index - 1]; if ((last->type == MMAP) && (last->u.mmap.addr + last->u.mmap.len == virt) && (last->u.mmap.prot == prot) && (last->u.mmap.fd == fd) && (last->u.mmap.offset + last->u.mmap.len == offset)) { last->u.mmap.len += len; return 0; } } if (hvc->index == ARRAY_SIZE(hvc->ops)) { ret = do_ops(hvc, ARRAY_SIZE(hvc->ops), 0); hvc->index = 0; } hvc->ops[hvc->index++] = ((struct host_vm_op) { .type = MMAP, .u = { .mmap = { .addr = virt, .len = len, .prot = prot, .fd = fd, .offset = offset } } }); return ret; } static int add_munmap(unsigned long addr, unsigned long len, struct host_vm_change *hvc) { struct host_vm_op *last; int ret = 0; if ((addr >= STUB_START) && (addr < STUB_END)) return -EINVAL; if (hvc->index != 0) { last = &hvc->ops[hvc->index - 1]; if ((last->type == MUNMAP) && (last->u.munmap.addr + last->u.mmap.len == addr)) { last->u.munmap.len += len; return 0; } } if (hvc->index == ARRAY_SIZE(hvc->ops)) { ret = do_ops(hvc, ARRAY_SIZE(hvc->ops), 0); hvc->index = 0; } hvc->ops[hvc->index++] = ((struct host_vm_op) { .type = MUNMAP, .u = { .munmap = { .addr = addr, .len = len } } }); return ret; } static int add_mprotect(unsigned long addr, unsigned long len, unsigned int prot, struct host_vm_change *hvc) { struct host_vm_op *last; int ret = 0; if (hvc->index != 0) { last = &hvc->ops[hvc->index - 1]; if ((last->type == MPROTECT) && (last->u.mprotect.addr + last->u.mprotect.len == addr) && (last->u.mprotect.prot == prot)) { last->u.mprotect.len += len; return 0; } } if (hvc->index == ARRAY_SIZE(hvc->ops)) { ret = do_ops(hvc, ARRAY_SIZE(hvc->ops), 0); hvc->index = 0; } hvc->ops[hvc->index++] = ((struct host_vm_op) { .type = MPROTECT, .u = { .mprotect = { .addr = addr, .len = len, .prot = prot } } }); return ret; } #define ADD_ROUND(n, inc) (((n) + (inc)) & ~((inc) - 1)) static inline int update_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, struct host_vm_change *hvc) { pte_t *pte; int r, w, x, prot, ret = 0; pte = pte_offset_kernel(pmd, addr); do { if ((addr >= STUB_START) && (addr < STUB_END)) continue; r = pte_read(*pte); w = pte_write(*pte); x = pte_exec(*pte); if (!pte_young(*pte)) { r = 0; w = 0; } else if (!pte_dirty(*pte)) w = 0; prot = ((r ? UM_PROT_READ : 0) | (w ? UM_PROT_WRITE : 0) | (x ? UM_PROT_EXEC : 0)); if (hvc->force || pte_newpage(*pte)) { if (pte_present(*pte)) ret = add_mmap(addr, pte_val(*pte) & PAGE_MASK, PAGE_SIZE, prot, hvc); else ret = add_munmap(addr, PAGE_SIZE, hvc); } else if (pte_newprot(*pte)) ret = add_mprotect(addr, PAGE_SIZE, prot, hvc); *pte = pte_mkuptodate(*pte); } while (pte++, addr += PAGE_SIZE, ((addr < end) && !ret)); return ret; } static inline int update_pmd_range(pud_t *pud, unsigned long addr, unsigned long end, struct host_vm_change *hvc) { pmd_t *pmd; unsigned long next; int ret = 0; pmd = pmd_offset(pud, addr); do { next = pmd_addr_end(addr, end); if (!pmd_present(*pmd)) { if (hvc->force || pmd_newpage(*pmd)) { ret = add_munmap(addr, next - addr, hvc); pmd_mkuptodate(*pmd); } } else ret = update_pte_range(pmd, addr, next, hvc); } while (pmd++, addr = next, ((addr < end) && !ret)); return ret; } static inline int update_pud_range(pgd_t *pgd, unsigned long addr, unsigned long end, struct host_vm_change *hvc) { pud_t *pud; unsigned long next; int ret = 0; pud = pud_offset(pgd, addr); do { next = pud_addr_end(addr, end); if (!pud_present(*pud)) { if (hvc->force || pud_newpage(*pud)) { ret = add_munmap(addr, next - addr, hvc); pud_mkuptodate(*pud); } } else ret = update_pmd_range(pud, addr, next, hvc); } while (pud++, addr = next, ((addr < end) && !ret)); return ret; } void fix_range_common(struct mm_struct *mm, unsigned long start_addr, unsigned long end_addr, int force) { pgd_t *pgd; struct host_vm_change hvc; unsigned long addr = start_addr, next; int ret = 0; hvc = INIT_HVC(mm, force); pgd = pgd_offset(mm, addr); do { next = pgd_addr_end(addr, end_addr); if (!pgd_present(*pgd)) { if (force || pgd_newpage(*pgd)) { ret = add_munmap(addr, next - addr, &hvc); pgd_mkuptodate(*pgd); } } else ret = update_pud_range(pgd, addr, next, &hvc); } while (pgd++, addr = next, ((addr < end_addr) && !ret)); if (!ret) ret = do_ops(&hvc, hvc.index, 1); /* This is not an else because ret is modified above */ if (ret) { printk(KERN_ERR "fix_range_common: failed, killing current " "process: %d\n", task_tgid_vnr(current)); /* We are under mmap_sem, release it such that current can terminate */ up_write(¤t->mm->mmap_sem); force_sig(SIGKILL, current); do_signal(); } } static int flush_tlb_kernel_range_common(unsigned long start, unsigned long end) { struct mm_struct *mm; pgd_t *pgd; pud_t *pud; pmd_t *pmd; pte_t *pte; unsigned long addr, last; int updated = 0, err; mm = &init_mm; for (addr = start; addr < end;) { pgd = pgd_offset(mm, addr); if (!pgd_present(*pgd)) { last = ADD_ROUND(addr, PGDIR_SIZE); if (last > end) last = end; if (pgd_newpage(*pgd)) { updated = 1; err = os_unmap_memory((void *) addr, last - addr); if (err < 0) panic("munmap failed, errno = %d\n", -err); } addr = last; continue; } pud = pud_offset(pgd, addr); if (!pud_present(*pud)) { last = ADD_ROUND(addr, PUD_SIZE); if (last > end) last = end; if (pud_newpage(*pud)) { updated = 1; err = os_unmap_memory((void *) addr, last - addr); if (err < 0) panic("munmap failed, errno = %d\n", -err); } addr = last; continue; } pmd = pmd_offset(pud, addr); if (!pmd_present(*pmd)) { last = ADD_ROUND(addr, PMD_SIZE); if (last > end) last = end; if (pmd_newpage(*pmd)) { updated = 1; err = os_unmap_memory((void *) addr, last - addr); if (err < 0) panic("munmap failed, errno = %d\n", -err); } addr = last; continue; } pte = pte_offset_kernel(pmd, addr); if (!pte_present(*pte) || pte_newpage(*pte)) { updated = 1; err = os_unmap_memory((void *) addr, PAGE_SIZE); if (err < 0) panic("munmap failed, errno = %d\n", -err); if (pte_present(*pte)) map_memory(addr, pte_val(*pte) & PAGE_MASK, PAGE_SIZE, 1, 1, 1); } else if (pte_newprot(*pte)) { updated = 1; os_protect_memory((void *) addr, PAGE_SIZE, 1, 1, 1); } addr += PAGE_SIZE; } return updated; } void flush_tlb_page(struct vm_area_struct *vma, unsigned long address) { pgd_t *pgd; pud_t *pud; pmd_t *pmd; pte_t *pte; struct mm_struct *mm = vma->vm_mm; void *flush = NULL; int r, w, x, prot, err = 0; struct mm_id *mm_id; address &= PAGE_MASK; pgd = pgd_offset(mm, address); if (!pgd_present(*pgd)) goto kill; pud = pud_offset(pgd, address); if (!pud_present(*pud)) goto kill; pmd = pmd_offset(pud, address); if (!pmd_present(*pmd)) goto kill; pte = pte_offset_kernel(pmd, address); r = pte_read(*pte); w = pte_write(*pte); x = pte_exec(*pte); if (!pte_young(*pte)) { r = 0; w = 0; } else if (!pte_dirty(*pte)) { w = 0; } mm_id = &mm->context.id; prot = ((r ? UM_PROT_READ : 0) | (w ? UM_PROT_WRITE : 0) | (x ? UM_PROT_EXEC : 0)); if (pte_newpage(*pte)) { if (pte_present(*pte)) { unsigned long long offset; int fd; fd = phys_mapping(pte_val(*pte) & PAGE_MASK, &offset); err = map(mm_id, address, PAGE_SIZE, prot, fd, offset, 1, &flush); } else err = unmap(mm_id, address, PAGE_SIZE, 1, &flush); } else if (pte_newprot(*pte)) err = protect(mm_id, address, PAGE_SIZE, prot, 1, &flush); if (err) goto kill; *pte = pte_mkuptodate(*pte); return; kill: printk(KERN_ERR "Failed to flush page for address 0x%lx\n", address); force_sig(SIGKILL, current); } pgd_t *pgd_offset_proc(struct mm_struct *mm, unsigned long address) { return pgd_offset(mm, address); } pud_t *pud_offset_proc(pgd_t *pgd, unsigned long address) { return pud_offset(pgd, address); } pmd_t *pmd_offset_proc(pud_t *pud, unsigned long address) { return pmd_offset(pud, address); } pte_t *pte_offset_proc(pmd_t *pmd, unsigned long address) { return pte_offset_kernel(pmd, address); } pte_t *addr_pte(struct task_struct *task, unsigned long addr) { pgd_t *pgd = pgd_offset(task->mm, addr); pud_t *pud = pud_offset(pgd, addr); pmd_t *pmd = pmd_offset(pud, addr); return pte_offset_map(pmd, addr); } void flush_tlb_all(void) { flush_tlb_mm(current->mm); } void flush_tlb_kernel_range(unsigned long start, unsigned long end) { flush_tlb_kernel_range_common(start, end); } void flush_tlb_kernel_vm(void) { flush_tlb_kernel_range_common(start_vm, end_vm); } void __flush_tlb_one(unsigned long addr) { flush_tlb_kernel_range_common(addr, addr + PAGE_SIZE); } static void fix_range(struct mm_struct *mm, unsigned long start_addr, unsigned long end_addr, int force) { fix_range_common(mm, start_addr, end_addr, force); } void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) { if (vma->vm_mm == NULL) flush_tlb_kernel_range_common(start, end); else fix_range(vma->vm_mm, start, end, 0); } EXPORT_SYMBOL(flush_tlb_range); void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start, unsigned long end) { /* * Don't bother flushing if this address space is about to be * destroyed. */ if (atomic_read(&mm->mm_users) == 0) return; fix_range(mm, start, end, 0); } void flush_tlb_mm(struct mm_struct *mm) { struct vm_area_struct *vma = mm->mmap; while (vma != NULL) { fix_range(mm, vma->vm_start, vma->vm_end, 0); vma = vma->vm_next; } } void force_flush_all(void) { struct mm_struct *mm = current->mm; struct vm_area_struct *vma = mm->mmap; while (vma != NULL) { fix_range(mm, vma->vm_start, vma->vm_end, 1); vma = vma->vm_next; } }