diff options
Diffstat (limited to 'mm/mmap.c')
| -rw-r--r-- | mm/mmap.c | 42 |
1 files changed, 27 insertions, 15 deletions
diff --git a/mm/mmap.c b/mm/mmap.c index 15678aa6ec7..a32d28ce31c 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -36,6 +36,10 @@ #define arch_mmap_check(addr, len, flags) (0) #endif +#ifndef arch_rebalance_pgtables +#define arch_rebalance_pgtables(addr, len) (addr) +#endif + static void unmap_region(struct mm_struct *mm, struct vm_area_struct *vma, struct vm_area_struct *prev, unsigned long start, unsigned long end); @@ -241,7 +245,7 @@ asmlinkage unsigned long sys_brk(unsigned long brk) down_write(&mm->mmap_sem); - if (brk < mm->end_code) + if (brk < mm->start_brk) goto out; /* @@ -251,7 +255,8 @@ asmlinkage unsigned long sys_brk(unsigned long brk) * not page aligned -Ram Gupta */ rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur; - if (rlim < RLIM_INFINITY && brk - mm->start_data > rlim) + if (rlim < RLIM_INFINITY && (brk - mm->start_brk) + + (mm->end_data - mm->start_data) > rlim) goto out; newbrk = PAGE_ALIGN(brk); @@ -1423,7 +1428,7 @@ get_unmapped_area(struct file *file, unsigned long addr, unsigned long len, if (addr & ~PAGE_MASK) return -EINVAL; - return addr; + return arch_rebalance_pgtables(addr, len); } EXPORT_SYMBOL(get_unmapped_area); @@ -1620,7 +1625,7 @@ static inline int expand_downwards(struct vm_area_struct *vma, return -ENOMEM; address &= PAGE_MASK; - error = security_file_mmap(0, 0, 0, 0, address, 1); + error = security_file_mmap(NULL, 0, 0, 0, address, 1); if (error) return error; @@ -1941,7 +1946,7 @@ unsigned long do_brk(unsigned long addr, unsigned long len) if (is_hugepage_only_range(mm, addr, len)) return -EINVAL; - error = security_file_mmap(0, 0, 0, 0, addr, 1); + error = security_file_mmap(NULL, 0, 0, 0, addr, 1); if (error) return error; @@ -2160,24 +2165,31 @@ int may_expand_vm(struct mm_struct *mm, unsigned long npages) } -static struct page *special_mapping_nopage(struct vm_area_struct *vma, - unsigned long address, int *type) +static int special_mapping_fault(struct vm_area_struct *vma, + struct vm_fault *vmf) { + pgoff_t pgoff; struct page **pages; - BUG_ON(address < vma->vm_start || address >= vma->vm_end); + /* + * special mappings have no vm_file, and in that case, the mm + * uses vm_pgoff internally. So we have to subtract it from here. + * We are allowed to do this because we are the mm; do not copy + * this code into drivers! + */ + pgoff = vmf->pgoff - vma->vm_pgoff; - address -= vma->vm_start; - for (pages = vma->vm_private_data; address > 0 && *pages; ++pages) - address -= PAGE_SIZE; + for (pages = vma->vm_private_data; pgoff && *pages; ++pages) + pgoff--; if (*pages) { struct page *page = *pages; get_page(page); - return page; + vmf->page = page; + return 0; } - return NOPAGE_SIGBUS; + return VM_FAULT_SIGBUS; } /* @@ -2189,7 +2201,7 @@ static void special_mapping_close(struct vm_area_struct *vma) static struct vm_operations_struct special_mapping_vmops = { .close = special_mapping_close, - .nopage = special_mapping_nopage, + .fault = special_mapping_fault, }; /* @@ -2215,7 +2227,7 @@ int install_special_mapping(struct mm_struct *mm, vma->vm_start = addr; vma->vm_end = addr + len; - vma->vm_flags = vm_flags | mm->def_flags; + vma->vm_flags = vm_flags | mm->def_flags | VM_DONTEXPAND; vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); vma->vm_ops = &special_mapping_vmops; |