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Diffstat (limited to 'linux-2.4-xen-sparse/mm/mprotect.c')
-rw-r--r--linux-2.4-xen-sparse/mm/mprotect.c344
1 files changed, 0 insertions, 344 deletions
diff --git a/linux-2.4-xen-sparse/mm/mprotect.c b/linux-2.4-xen-sparse/mm/mprotect.c
deleted file mode 100644
index 9d2ed3c24c..0000000000
--- a/linux-2.4-xen-sparse/mm/mprotect.c
+++ /dev/null
@@ -1,344 +0,0 @@
-/*
- * linux/mm/mprotect.c
- *
- * (C) Copyright 1994 Linus Torvalds
- */
-#include <linux/slab.h>
-#include <linux/smp_lock.h>
-#include <linux/shm.h>
-#include <linux/mman.h>
-
-#include <asm/uaccess.h>
-#include <asm/pgalloc.h>
-#include <asm/pgtable.h>
-
-static inline void change_pte_range(pmd_t * pmd, unsigned long address,
- unsigned long size, pgprot_t newprot)
-{
- pte_t * pte;
- unsigned long end;
-
- if (pmd_none(*pmd))
- return;
- if (pmd_bad(*pmd)) {
- pmd_ERROR(*pmd);
- pmd_clear(pmd);
- return;
- }
- pte = pte_offset(pmd, address);
- address &= ~PMD_MASK;
- end = address + size;
- if (end > PMD_SIZE)
- end = PMD_SIZE;
- do {
- if (pte_present(*pte)) {
- pte_t entry;
-
- /* Avoid an SMP race with hardware updated dirty/clean
- * bits by wiping the pte and then setting the new pte
- * into place.
- */
- entry = ptep_get_and_clear(pte);
- set_pte(pte, pte_modify(entry, newprot));
- }
- address += PAGE_SIZE;
- pte++;
- } while (address && (address < end));
-}
-
-static inline void change_pmd_range(pgd_t * pgd, unsigned long address,
- unsigned long size, pgprot_t newprot)
-{
- pmd_t * pmd;
- unsigned long end;
-
- if (pgd_none(*pgd))
- return;
- if (pgd_bad(*pgd)) {
- pgd_ERROR(*pgd);
- pgd_clear(pgd);
- return;
- }
- pmd = pmd_offset(pgd, address);
- address &= ~PGDIR_MASK;
- end = address + size;
- if (end > PGDIR_SIZE)
- end = PGDIR_SIZE;
- do {
- change_pte_range(pmd, address, end - address, newprot);
- address = (address + PMD_SIZE) & PMD_MASK;
- pmd++;
- } while (address && (address < end));
-}
-
-static void change_protection(unsigned long start, unsigned long end, pgprot_t newprot)
-{
- pgd_t *dir;
- unsigned long beg = start;
-
- dir = pgd_offset(current->mm, start);
- flush_cache_range(current->mm, beg, end);
- if (start >= end)
- BUG();
- spin_lock(&current->mm->page_table_lock);
- do {
- change_pmd_range(dir, start, end - start, newprot);
- start = (start + PGDIR_SIZE) & PGDIR_MASK;
- dir++;
- } while (start && (start < end));
- spin_unlock(&current->mm->page_table_lock);
- flush_tlb_range(current->mm, beg, end);
- return;
-}
-
-static inline int mprotect_fixup_all(struct vm_area_struct * vma, struct vm_area_struct ** pprev,
- int newflags, pgprot_t prot)
-{
- struct vm_area_struct * prev = *pprev;
- struct mm_struct * mm = vma->vm_mm;
-
- if (prev && prev->vm_end == vma->vm_start && can_vma_merge(prev, newflags) &&
- !vma->vm_file && !(vma->vm_flags & VM_SHARED)) {
- spin_lock(&mm->page_table_lock);
- prev->vm_end = vma->vm_end;
- __vma_unlink(mm, vma, prev);
- spin_unlock(&mm->page_table_lock);
-
- kmem_cache_free(vm_area_cachep, vma);
- mm->map_count--;
-
- return 0;
- }
-
- spin_lock(&mm->page_table_lock);
- vma->vm_flags = newflags;
- vma->vm_page_prot = prot;
- spin_unlock(&mm->page_table_lock);
-
- *pprev = vma;
-
- return 0;
-}
-
-static inline int mprotect_fixup_start(struct vm_area_struct * vma, struct vm_area_struct ** pprev,
- unsigned long end,
- int newflags, pgprot_t prot)
-{
- struct vm_area_struct * n, * prev = *pprev;
-
- *pprev = vma;
-
- if (prev && prev->vm_end == vma->vm_start && can_vma_merge(prev, newflags) &&
- !vma->vm_file && !(vma->vm_flags & VM_SHARED)) {
- spin_lock(&vma->vm_mm->page_table_lock);
- prev->vm_end = end;
- vma->vm_start = end;
- spin_unlock(&vma->vm_mm->page_table_lock);
-
- return 0;
- }
- n = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
- if (!n)
- return -ENOMEM;
- *n = *vma;
- n->vm_end = end;
- n->vm_flags = newflags;
- n->vm_raend = 0;
- n->vm_page_prot = prot;
- if (n->vm_file)
- get_file(n->vm_file);
- if (n->vm_ops && n->vm_ops->open)
- n->vm_ops->open(n);
- vma->vm_pgoff += (end - vma->vm_start) >> PAGE_SHIFT;
- lock_vma_mappings(vma);
- spin_lock(&vma->vm_mm->page_table_lock);
- vma->vm_start = end;
- __insert_vm_struct(current->mm, n);
- spin_unlock(&vma->vm_mm->page_table_lock);
- unlock_vma_mappings(vma);
-
- return 0;
-}
-
-static inline int mprotect_fixup_end(struct vm_area_struct * vma, struct vm_area_struct ** pprev,
- unsigned long start,
- int newflags, pgprot_t prot)
-{
- struct vm_area_struct * n;
-
- n = kmem_cache_alloc(vm_area_cachep, GFP_KERNEL);
- if (!n)
- return -ENOMEM;
- *n = *vma;
- n->vm_start = start;
- n->vm_pgoff += (n->vm_start - vma->vm_start) >> PAGE_SHIFT;
- n->vm_flags = newflags;
- n->vm_raend = 0;
- n->vm_page_prot = prot;
- if (n->vm_file)
- get_file(n->vm_file);
- if (n->vm_ops && n->vm_ops->open)
- n->vm_ops->open(n);
- lock_vma_mappings(vma);
- spin_lock(&vma->vm_mm->page_table_lock);
- vma->vm_end = start;
- __insert_vm_struct(current->mm, n);
- spin_unlock(&vma->vm_mm->page_table_lock);
- unlock_vma_mappings(vma);
-
- *pprev = n;
-
- return 0;
-}
-
-static inline int mprotect_fixup_middle(struct vm_area_struct * vma, struct vm_area_struct ** pprev,
- unsigned long start, unsigned long end,
- int newflags, pgprot_t prot)
-{
- struct vm_area_struct * left, * right;
-
- left = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
- if (!left)
- return -ENOMEM;
- right = kmem_cache_alloc(vm_area_cachep, SLAB_KERNEL);
- if (!right) {
- kmem_cache_free(vm_area_cachep, left);
- return -ENOMEM;
- }
- *left = *vma;
- *right = *vma;
- left->vm_end = start;
- right->vm_start = end;
- right->vm_pgoff += (right->vm_start - left->vm_start) >> PAGE_SHIFT;
- left->vm_raend = 0;
- right->vm_raend = 0;
- if (vma->vm_file)
- atomic_add(2,&vma->vm_file->f_count);
- if (vma->vm_ops && vma->vm_ops->open) {
- vma->vm_ops->open(left);
- vma->vm_ops->open(right);
- }
- vma->vm_pgoff += (start - vma->vm_start) >> PAGE_SHIFT;
- vma->vm_raend = 0;
- vma->vm_page_prot = prot;
- lock_vma_mappings(vma);
- spin_lock(&vma->vm_mm->page_table_lock);
- vma->vm_start = start;
- vma->vm_end = end;
- vma->vm_flags = newflags;
- __insert_vm_struct(current->mm, left);
- __insert_vm_struct(current->mm, right);
- spin_unlock(&vma->vm_mm->page_table_lock);
- unlock_vma_mappings(vma);
-
- *pprev = right;
-
- return 0;
-}
-
-static int mprotect_fixup(struct vm_area_struct * vma, struct vm_area_struct ** pprev,
- unsigned long start, unsigned long end, unsigned int newflags)
-{
- pgprot_t newprot;
- int error;
-
- if (newflags == vma->vm_flags) {
- *pprev = vma;
- return 0;
- }
- newprot = protection_map[newflags & 0xf];
- if (start == vma->vm_start) {
- if (end == vma->vm_end)
- error = mprotect_fixup_all(vma, pprev, newflags, newprot);
- else
- error = mprotect_fixup_start(vma, pprev, end, newflags, newprot);
- } else if (end == vma->vm_end)
- error = mprotect_fixup_end(vma, pprev, start, newflags, newprot);
- else
- error = mprotect_fixup_middle(vma, pprev, start, end, newflags, newprot);
-
- if (error)
- return error;
-
- change_protection(start, end, newprot);
- return 0;
-}
-
-asmlinkage long sys_mprotect(unsigned long start, size_t len, unsigned long prot)
-{
- unsigned long nstart, end, tmp;
- struct vm_area_struct * vma, * next, * prev;
- int error = -EINVAL;
-
- if (start & ~PAGE_MASK)
- return -EINVAL;
- len = PAGE_ALIGN(len);
- end = start + len;
- if (end < start)
- return -ENOMEM;
- if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC))
- return -EINVAL;
- if (end == start)
- return 0;
-
- down_write(&current->mm->mmap_sem);
-
- vma = find_vma_prev(current->mm, start, &prev);
- error = -ENOMEM;
- if (!vma || vma->vm_start > start)
- goto out;
-
-#if defined(CONFIG_XEN_PRIVILEGED_GUEST)
- /* mprotect() unsupported for I/O mappings in Xenolinux. */
- error = -EINVAL;
- if (vma->vm_flags & VM_IO)
- goto out;
-#endif
-
- for (nstart = start ; ; ) {
- unsigned int newflags;
- int last = 0;
-
- /* Here we know that vma->vm_start <= nstart < vma->vm_end. */
-
- newflags = prot | (vma->vm_flags & ~(PROT_READ | PROT_WRITE | PROT_EXEC));
- if ((newflags & ~(newflags >> 4)) & 0xf) {
- error = -EACCES;
- goto out;
- }
-
- if (vma->vm_end > end) {
- error = mprotect_fixup(vma, &prev, nstart, end, newflags);
- goto out;
- }
- if (vma->vm_end == end)
- last = 1;
-
- tmp = vma->vm_end;
- next = vma->vm_next;
- error = mprotect_fixup(vma, &prev, nstart, tmp, newflags);
- if (error)
- goto out;
- if (last)
- break;
- nstart = tmp;
- vma = next;
- if (!vma || vma->vm_start != nstart) {
- error = -ENOMEM;
- goto out;
- }
- }
- if (next && prev->vm_end == next->vm_start && can_vma_merge(next, prev->vm_flags) &&
- !prev->vm_file && !(prev->vm_flags & VM_SHARED)) {
- spin_lock(&prev->vm_mm->page_table_lock);
- prev->vm_end = next->vm_end;
- __vma_unlink(prev->vm_mm, next, prev);
- spin_unlock(&prev->vm_mm->page_table_lock);
-
- kmem_cache_free(vm_area_cachep, next);
- prev->vm_mm->map_count--;
- }
-out:
- up_write(&current->mm->mmap_sem);
- return error;
-}
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