X-Git-Url: http://git.monstr.eu/?a=blobdiff_plain;f=mm%2Fnommu.c;h=57ba243c6a37f466962891f6d71b7dc0910ffce7;hb=04a357b1f6f0b6f7c8689361fa8802e8e35d02ad;hp=5b83938ecb67cf4533c4a30e997cea3e3111b285;hpb=585a78c1f77be305b1f6adad392f16047fb66ffd;p=linux-2.6-microblaze.git diff --git a/mm/nommu.c b/mm/nommu.c index 5b83938ecb67..57ba243c6a37 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -173,7 +173,7 @@ static void *__vmalloc_user_flags(unsigned long size, gfp_t flags) mmap_write_lock(current->mm); vma = find_vma(current->mm, (unsigned long)ret); if (vma) - vma->vm_flags |= VM_USERMAP; + vm_flags_set(vma, VM_USERMAP); mmap_write_unlock(current->mm); } @@ -544,19 +544,6 @@ static void put_nommu_region(struct vm_region *region) __put_nommu_region(region); } -void vma_mas_store(struct vm_area_struct *vma, struct ma_state *mas) -{ - mas_set_range(mas, vma->vm_start, vma->vm_end - 1); - mas_store_prealloc(mas, vma); -} - -void vma_mas_remove(struct vm_area_struct *vma, struct ma_state *mas) -{ - mas->index = vma->vm_start; - mas->last = vma->vm_end - 1; - mas_store_prealloc(mas, NULL); -} - static void setup_vma_to_mm(struct vm_area_struct *vma, struct mm_struct *mm) { vma->vm_mm = mm; @@ -573,44 +560,6 @@ static void setup_vma_to_mm(struct vm_area_struct *vma, struct mm_struct *mm) } } -/* - * mas_add_vma_to_mm() - Maple state variant of add_mas_to_mm(). - * @mas: The maple state with preallocations. - * @mm: The mm_struct - * @vma: The vma to add - * - */ -static void mas_add_vma_to_mm(struct ma_state *mas, struct mm_struct *mm, - struct vm_area_struct *vma) -{ - BUG_ON(!vma->vm_region); - - setup_vma_to_mm(vma, mm); - mm->map_count++; - - /* add the VMA to the tree */ - vma_mas_store(vma, mas); -} - -/* - * add a VMA into a process's mm_struct in the appropriate place in the list - * and tree and add to the address space's page tree also if not an anonymous - * page - * - should be called with mm->mmap_lock held writelocked - */ -static int add_vma_to_mm(struct mm_struct *mm, struct vm_area_struct *vma) -{ - MA_STATE(mas, &mm->mm_mt, vma->vm_start, vma->vm_end); - - if (mas_preallocate(&mas, vma, GFP_KERNEL)) { - pr_warn("Allocation of vma tree for process %d failed\n", - current->pid); - return -ENOMEM; - } - mas_add_vma_to_mm(&mas, mm, vma); - return 0; -} - static void cleanup_vma_from_mm(struct vm_area_struct *vma) { vma->vm_mm->map_count--; @@ -626,14 +575,15 @@ static void cleanup_vma_from_mm(struct vm_area_struct *vma) i_mmap_unlock_write(mapping); } } + /* * delete a VMA from its owning mm_struct and address space */ static int delete_vma_from_mm(struct vm_area_struct *vma) { - MA_STATE(mas, &vma->vm_mm->mm_mt, 0, 0); + VMA_ITERATOR(vmi, vma->vm_mm, vma->vm_start); - if (mas_preallocate(&mas, vma, GFP_KERNEL)) { + if (vma_iter_prealloc(&vmi)) { pr_warn("Allocation of vma tree for process %d failed\n", current->pid); return -ENOMEM; @@ -641,10 +591,9 @@ static int delete_vma_from_mm(struct vm_area_struct *vma) cleanup_vma_from_mm(vma); /* remove from the MM's tree and list */ - vma_mas_remove(vma, &mas); + vma_iter_clear(&vmi, vma->vm_start, vma->vm_end); return 0; } - /* * destroy a VMA record */ @@ -675,9 +624,9 @@ EXPORT_SYMBOL(find_vma_intersection); */ struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr) { - MA_STATE(mas, &mm->mm_mt, addr, addr); + VMA_ITERATOR(vmi, mm, addr); - return mas_walk(&mas); + return vma_iter_load(&vmi); } EXPORT_SYMBOL(find_vma); @@ -709,9 +658,9 @@ static struct vm_area_struct *find_vma_exact(struct mm_struct *mm, { struct vm_area_struct *vma; unsigned long end = addr + len; - MA_STATE(mas, &mm->mm_mt, addr, addr); + VMA_ITERATOR(vmi, mm, addr); - vma = mas_walk(&mas); + vma = vma_iter_load(&vmi); if (!vma) return NULL; if (vma->vm_start != addr) @@ -892,29 +841,36 @@ static unsigned long determine_vm_flags(struct file *file, unsigned long vm_flags; vm_flags = calc_vm_prot_bits(prot, 0) | calc_vm_flag_bits(flags); - /* vm_flags |= mm->def_flags; */ - if (!(capabilities & NOMMU_MAP_DIRECT)) { - /* attempt to share read-only copies of mapped file chunks */ + if (!file) { + /* + * MAP_ANONYMOUS. MAP_SHARED is mapped to MAP_PRIVATE, because + * there is no fork(). + */ vm_flags |= VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC; - if (file && !(prot & PROT_WRITE)) - vm_flags |= VM_MAYSHARE; + } else if (flags & MAP_PRIVATE) { + /* MAP_PRIVATE file mapping */ + if (capabilities & NOMMU_MAP_DIRECT) + vm_flags |= (capabilities & NOMMU_VMFLAGS); + else + vm_flags |= VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC; + + if (!(prot & PROT_WRITE) && !current->ptrace) + /* + * R/O private file mapping which cannot be used to + * modify memory, especially also not via active ptrace + * (e.g., set breakpoints) or later by upgrading + * permissions (no mprotect()). We can try overlaying + * the file mapping, which will work e.g., on chardevs, + * ramfs/tmpfs/shmfs and romfs/cramf. + */ + vm_flags |= VM_MAYOVERLAY; } else { - /* overlay a shareable mapping on the backing device or inode - * if possible - used for chardevs, ramfs/tmpfs/shmfs and - * romfs/cramfs */ - vm_flags |= VM_MAYSHARE | (capabilities & NOMMU_VMFLAGS); - if (flags & MAP_SHARED) - vm_flags |= VM_SHARED; + /* MAP_SHARED file mapping: NOMMU_MAP_DIRECT is set. */ + vm_flags |= VM_SHARED | VM_MAYSHARE | + (capabilities & NOMMU_VMFLAGS); } - /* refuse to let anyone share private mappings with this process if - * it's being traced - otherwise breakpoints set in it may interfere - * with another untraced process - */ - if ((flags & MAP_PRIVATE) && current->ptrace) - vm_flags &= ~VM_MAYSHARE; - return vm_flags; } @@ -952,15 +908,18 @@ static int do_mmap_private(struct vm_area_struct *vma, void *base; int ret, order; - /* invoke the file's mapping function so that it can keep track of - * shared mappings on devices or memory - * - VM_MAYSHARE will be set if it may attempt to share + /* + * Invoke the file's mapping function so that it can keep track of + * shared mappings on devices or memory. VM_MAYOVERLAY will be set if + * it may attempt to share, which will make is_nommu_shared_mapping() + * happy. */ if (capabilities & NOMMU_MAP_DIRECT) { ret = call_mmap(vma->vm_file, vma); + /* shouldn't return success if we're not sharing */ + if (WARN_ON_ONCE(!is_nommu_shared_mapping(vma->vm_flags))) + ret = -ENOSYS; if (ret == 0) { - /* shouldn't return success if we're not sharing */ - BUG_ON(!(vma->vm_flags & VM_MAYSHARE)); vma->vm_region->vm_top = vma->vm_region->vm_end; return 0; } @@ -991,7 +950,8 @@ static int do_mmap_private(struct vm_area_struct *vma, atomic_long_add(total, &mmap_pages_allocated); - region->vm_flags = vma->vm_flags |= VM_MAPPED_COPY; + vm_flags_set(vma, VM_MAPPED_COPY); + region->vm_flags = vma->vm_flags; region->vm_start = (unsigned long) base; region->vm_end = region->vm_start + len; region->vm_top = region->vm_start + (total << PAGE_SHIFT); @@ -1052,7 +1012,7 @@ unsigned long do_mmap(struct file *file, vm_flags_t vm_flags; unsigned long capabilities, result; int ret; - MA_STATE(mas, ¤t->mm->mm_mt, 0, 0); + VMA_ITERATOR(vmi, current->mm, 0); *populate = 0; @@ -1081,14 +1041,14 @@ unsigned long do_mmap(struct file *file, if (!vma) goto error_getting_vma; - if (mas_preallocate(&mas, vma, GFP_KERNEL)) - goto error_maple_preallocate; + if (vma_iter_prealloc(&vmi)) + goto error_vma_iter_prealloc; region->vm_usage = 1; region->vm_flags = vm_flags; region->vm_pgoff = pgoff; - vma->vm_flags = vm_flags; + vm_flags_init(vma, vm_flags); vma->vm_pgoff = pgoff; if (file) { @@ -1106,7 +1066,7 @@ unsigned long do_mmap(struct file *file, * these cases, sharing is handled in the driver or filesystem rather * than here */ - if (vm_flags & VM_MAYSHARE) { + if (is_nommu_shared_mapping(vm_flags)) { struct vm_region *pregion; unsigned long pglen, rpglen, pgend, rpgend, start; @@ -1116,7 +1076,7 @@ unsigned long do_mmap(struct file *file, for (rb = rb_first(&nommu_region_tree); rb; rb = rb_next(rb)) { pregion = rb_entry(rb, struct vm_region, vm_rb); - if (!(pregion->vm_flags & VM_MAYSHARE)) + if (!is_nommu_shared_mapping(pregion->vm_flags)) continue; /* search for overlapping mappings on the same file */ @@ -1152,7 +1112,7 @@ unsigned long do_mmap(struct file *file, vma->vm_end = start + len; if (pregion->vm_flags & VM_MAPPED_COPY) - vma->vm_flags |= VM_MAPPED_COPY; + vm_flags_set(vma, VM_MAPPED_COPY); else { ret = do_mmap_shared_file(vma); if (ret < 0) { @@ -1224,7 +1184,11 @@ unsigned long do_mmap(struct file *file, current->mm->total_vm += len >> PAGE_SHIFT; share: - mas_add_vma_to_mm(&mas, current->mm, vma); + BUG_ON(!vma->vm_region); + setup_vma_to_mm(vma, current->mm); + current->mm->map_count++; + /* add the VMA to the tree */ + vma_iter_store(&vmi, vma); /* we flush the region from the icache only when the first executable * mapping of it is made */ @@ -1240,7 +1204,7 @@ share: error_just_free: up_write(&nommu_region_sem); error: - mas_destroy(&mas); + vma_iter_free(&vmi); if (region->vm_file) fput(region->vm_file); kmem_cache_free(vm_region_jar, region); @@ -1268,7 +1232,7 @@ error_getting_region: show_free_areas(0, NULL); return -ENOMEM; -error_maple_preallocate: +error_vma_iter_prealloc: kmem_cache_free(vm_region_jar, region); vm_area_free(vma); pr_warn("Allocation of vma tree for process %d failed\n", current->pid); @@ -1334,13 +1298,13 @@ SYSCALL_DEFINE1(old_mmap, struct mmap_arg_struct __user *, arg) * split a vma into two pieces at address 'addr', a new vma is allocated either * for the first part or the tail. */ -int split_vma(struct mm_struct *mm, struct vm_area_struct *vma, +int split_vma(struct vma_iterator *vmi, struct vm_area_struct *vma, unsigned long addr, int new_below) { struct vm_area_struct *new; struct vm_region *region; unsigned long npages; - MA_STATE(mas, &mm->mm_mt, vma->vm_start, vma->vm_end); + struct mm_struct *mm; /* we're only permitted to split anonymous regions (these should have * only a single usage on the region) */ @@ -1359,10 +1323,10 @@ int split_vma(struct mm_struct *mm, struct vm_area_struct *vma, if (!new) goto err_vma_dup; - if (mas_preallocate(&mas, vma, GFP_KERNEL)) { + if (vma_iter_prealloc(vmi)) { pr_warn("Allocation of vma tree for process %d failed\n", current->pid); - goto err_mas_preallocate; + goto err_vmi_preallocate; } /* most fields are the same, copy all, and then fixup */ @@ -1396,13 +1360,11 @@ int split_vma(struct mm_struct *mm, struct vm_area_struct *vma, setup_vma_to_mm(vma, mm); setup_vma_to_mm(new, mm); - mas_set_range(&mas, vma->vm_start, vma->vm_end - 1); - mas_store(&mas, vma); - vma_mas_store(new, &mas); + vma_iter_store(vmi, new); mm->map_count++; return 0; -err_mas_preallocate: +err_vmi_preallocate: vm_area_free(new); err_vma_dup: kmem_cache_free(vm_region_jar, region); @@ -1413,7 +1375,7 @@ err_vma_dup: * shrink a VMA by removing the specified chunk from either the beginning or * the end */ -static int shrink_vma(struct mm_struct *mm, +static int vmi_shrink_vma(struct vma_iterator *vmi, struct vm_area_struct *vma, unsigned long from, unsigned long to) { @@ -1421,14 +1383,19 @@ static int shrink_vma(struct mm_struct *mm, /* adjust the VMA's pointers, which may reposition it in the MM's tree * and list */ - if (delete_vma_from_mm(vma)) + if (vma_iter_prealloc(vmi)) { + pr_warn("Allocation of vma tree for process %d failed\n", + current->pid); return -ENOMEM; - if (from > vma->vm_start) + } + + if (from > vma->vm_start) { + vma_iter_clear(vmi, from, vma->vm_end); vma->vm_end = from; - else + } else { + vma_iter_clear(vmi, vma->vm_start, to); vma->vm_start = to; - if (add_vma_to_mm(mm, vma)) - return -ENOMEM; + } /* cut the backing region down to size */ region = vma->vm_region; @@ -1456,7 +1423,7 @@ static int shrink_vma(struct mm_struct *mm, */ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len, struct list_head *uf) { - MA_STATE(mas, &mm->mm_mt, start, start); + VMA_ITERATOR(vmi, mm, start); struct vm_area_struct *vma; unsigned long end; int ret = 0; @@ -1468,7 +1435,7 @@ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len, struct list end = start + len; /* find the first potentially overlapping VMA */ - vma = mas_find(&mas, end - 1); + vma = vma_find(&vmi, end); if (!vma) { static int limit; if (limit < 5) { @@ -1487,7 +1454,7 @@ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len, struct list return -EINVAL; if (end == vma->vm_end) goto erase_whole_vma; - vma = mas_next(&mas, end - 1); + vma = vma_find(&vmi, end); } while (vma); return -EINVAL; } else { @@ -1501,11 +1468,11 @@ int do_munmap(struct mm_struct *mm, unsigned long start, size_t len, struct list if (end != vma->vm_end && offset_in_page(end)) return -EINVAL; if (start != vma->vm_start && end != vma->vm_end) { - ret = split_vma(mm, vma, start, 1); + ret = split_vma(&vmi, vma, start, 1); if (ret < 0) return ret; } - return shrink_vma(mm, vma, start, end); + return vmi_shrink_vma(&vmi, vma, start, end); } erase_whole_vma: @@ -1600,7 +1567,7 @@ static unsigned long do_mremap(unsigned long addr, if (vma->vm_end != vma->vm_start + old_len) return (unsigned long) -EFAULT; - if (vma->vm_flags & VM_MAYSHARE) + if (is_nommu_shared_mapping(vma->vm_flags)) return (unsigned long) -EPERM; if (new_len > vma->vm_region->vm_end - vma->vm_region->vm_start) @@ -1635,7 +1602,7 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr, if (addr != (pfn << PAGE_SHIFT)) return -EINVAL; - vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP; + vm_flags_set(vma, VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP); return 0; } EXPORT_SYMBOL(remap_pfn_range);