X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=mm%2Fmprotect.c;h=05dc34246b20e29e46545af8e744c013d6f5ecfc;hb=000af042c9fbf7f86f68f59be2836111d3331aba;hp=5db73dcd2bc3e4c6899b9a81b5b000817cd5c511;hpb=cace1c4618b6c6442b7dc973e935e7f3268e4aa7;p=linux-2.6.git diff --git a/mm/mprotect.c b/mm/mprotect.c index 5db73dcd2..05dc34246 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -30,8 +30,9 @@ static void change_pte_range(struct mm_struct *mm, pmd_t *pmd, unsigned long addr, unsigned long end, pgprot_t newprot) { pte_t *pte; + spinlock_t *ptl; - pte = pte_offset_map(pmd, addr); + pte = pte_offset_map_lock(mm, pmd, addr, &ptl); do { if (pte_present(*pte)) { pte_t ptent; @@ -45,7 +46,7 @@ static void change_pte_range(struct mm_struct *mm, pmd_t *pmd, lazy_mmu_prot_update(ptent); } } while (pte++, addr += PAGE_SIZE, addr != end); - pte_unmap(pte - 1); + pte_unmap_unlock(pte - 1, ptl); } static inline void change_pmd_range(struct mm_struct *mm, pud_t *pud, @@ -89,7 +90,6 @@ static void change_protection(struct vm_area_struct *vma, BUG_ON(addr >= end); pgd = pgd_offset(mm, addr); flush_cache_range(vma, addr, end); - spin_lock(&mm->page_table_lock); do { next = pgd_addr_end(addr, end); if (pgd_none_or_clear_bad(pgd)) @@ -97,7 +97,6 @@ static void change_protection(struct vm_area_struct *vma, change_pud_range(mm, pgd, addr, next, newprot); } while (pgd++, addr = next, addr != end); flush_tlb_range(vma, start, end); - spin_unlock(&mm->page_table_lock); } static int @@ -126,7 +125,7 @@ mprotect_fixup(struct vm_area_struct *vma, struct vm_area_struct **pprev, * a MAP_NORESERVE private mapping to writable will now reserve. */ if (newflags & VM_WRITE) { - if (!(oldflags & (VM_ACCOUNT|VM_WRITE|VM_SHARED|VM_HUGETLB))) { + if (!(oldflags & (VM_ACCOUNT|VM_WRITE|VM_SHARED))) { charged = nrpages; if (security_vm_enough_memory(charged)) return -ENOMEM; @@ -170,9 +169,12 @@ success: vma->vm_page_prot = newprot; if (oldflags & VM_EXEC) arch_remove_exec_range(current->mm, old_end); - change_protection(vma, start, end, newprot); - __vm_stat_account(mm, oldflags, vma->vm_file, -nrpages); - __vm_stat_account(mm, newflags, vma->vm_file, nrpages); + if (is_vm_hugetlb_page(vma)) + hugetlb_change_protection(vma, start, end, newprot); + else + change_protection(vma, start, end, newprot); + vm_stat_account(mm, oldflags, vma->vm_file, -nrpages); + vm_stat_account(mm, newflags, vma->vm_file, nrpages); return 0; fail: @@ -181,8 +183,7 @@ fail: } asmlinkage long -do_mprotect(struct mm_struct *mm, unsigned long start, size_t len, - unsigned long prot) +sys_mprotect(unsigned long start, size_t len, unsigned long prot) { unsigned long vm_flags, nstart, end, tmp, reqprot; struct vm_area_struct *vma, *prev; @@ -213,9 +214,9 @@ do_mprotect(struct mm_struct *mm, unsigned long start, size_t len, vm_flags = calc_vm_prot_bits(prot); - down_write(&mm->mmap_sem); + down_write(¤t->mm->mmap_sem); - vma = find_vma_prev(mm, start, &prev); + vma = find_vma_prev(current->mm, start, &prev); error = -ENOMEM; if (!vma) goto out; @@ -245,14 +246,10 @@ do_mprotect(struct mm_struct *mm, unsigned long start, size_t len, /* Here we know that vma->vm_start <= nstart < vma->vm_end. */ - if (is_vm_hugetlb_page(vma)) { - error = -EACCES; - goto out; - } - newflags = vm_flags | (vma->vm_flags & ~(VM_READ | VM_WRITE | VM_EXEC)); - if ((newflags & ~(newflags >> 4)) & 0xf) { + /* newflags >> 4 shift VM_MAY% in place of VM_% */ + if ((newflags & ~(newflags >> 4)) & (VM_READ | VM_WRITE | VM_EXEC)) { error = -EACCES; goto out; } @@ -281,11 +278,6 @@ do_mprotect(struct mm_struct *mm, unsigned long start, size_t len, } } out: - up_write(&mm->mmap_sem); + up_write(¤t->mm->mmap_sem); return error; } - -asmlinkage long sys_mprotect(unsigned long start, size_t len, unsigned long prot) -{ - return(do_mprotect(current->mm, start, len, prot)); -}