diff options
| -rw-r--r-- | include/linux/mm_types.h | 2 | ||||
| -rw-r--r-- | kernel/fork.c | 7 | ||||
| -rw-r--r-- | mm/mmap.c | 21 | ||||
| -rw-r--r-- | mm/nommu.c | 7 |
4 files changed, 28 insertions, 9 deletions
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index 84a524afb3d..9d12ed56bfb 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -138,7 +138,7 @@ struct vm_area_struct { within vm_mm. */ /* linked list of VM areas per task, sorted by address */ - struct vm_area_struct *vm_next; + struct vm_area_struct *vm_next, *vm_prev; pgprot_t vm_page_prot; /* Access permissions of this VMA. */ unsigned long vm_flags; /* Flags, see mm.h. */ diff --git a/kernel/fork.c b/kernel/fork.c index ce2f5859933..9f3b066bf73 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -277,7 +277,7 @@ out: #ifdef CONFIG_MMU static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) { - struct vm_area_struct *mpnt, *tmp, **pprev; + struct vm_area_struct *mpnt, *tmp, *prev, **pprev; struct rb_node **rb_link, *rb_parent; int retval; unsigned long charge; @@ -305,6 +305,7 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) if (retval) goto out; + prev = NULL; for (mpnt = oldmm->mmap; mpnt; mpnt = mpnt->vm_next) { struct file *file; @@ -333,7 +334,7 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) vma_set_policy(tmp, pol); tmp->vm_flags &= ~VM_LOCKED; tmp->vm_mm = mm; - tmp->vm_next = NULL; + tmp->vm_next = tmp->vm_prev = NULL; anon_vma_link(tmp); file = tmp->vm_file; if (file) { @@ -367,6 +368,8 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) */ *pprev = tmp; pprev = &tmp->vm_next; + tmp->vm_prev = prev; + prev = tmp; __vma_link_rb(mm, tmp, rb_link, rb_parent); rb_link = &tmp->vm_rb.rb_right; diff --git a/mm/mmap.c b/mm/mmap.c index ae197468b35..b309c75b497 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -389,17 +389,23 @@ static inline void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma, struct vm_area_struct *prev, struct rb_node *rb_parent) { + struct vm_area_struct *next; + + vma->vm_prev = prev; if (prev) { - vma->vm_next = prev->vm_next; + next = prev->vm_next; prev->vm_next = vma; } else { mm->mmap = vma; if (rb_parent) - vma->vm_next = rb_entry(rb_parent, + next = rb_entry(rb_parent, struct vm_area_struct, vm_rb); else - vma->vm_next = NULL; + next = NULL; } + vma->vm_next = next; + if (next) + next->vm_prev = vma; } void __vma_link_rb(struct mm_struct *mm, struct vm_area_struct *vma, @@ -487,7 +493,11 @@ static inline void __vma_unlink(struct mm_struct *mm, struct vm_area_struct *vma, struct vm_area_struct *prev) { - prev->vm_next = vma->vm_next; + struct vm_area_struct *next = vma->vm_next; + + prev->vm_next = next; + if (next) + next->vm_prev = prev; rb_erase(&vma->vm_rb, &mm->mm_rb); if (mm->mmap_cache == vma) mm->mmap_cache = prev; @@ -1798,6 +1808,7 @@ detach_vmas_to_be_unmapped(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long addr; insertion_point = (prev ? &prev->vm_next : &mm->mmap); + vma->vm_prev = NULL; do { rb_erase(&vma->vm_rb, &mm->mm_rb); mm->map_count--; @@ -1805,6 +1816,8 @@ detach_vmas_to_be_unmapped(struct mm_struct *mm, struct vm_area_struct *vma, vma = vma->vm_next; } while (vma && vma->vm_start < end); *insertion_point = vma; + if (vma) + vma->vm_prev = prev; tail_vma->vm_next = NULL; if (mm->unmap_area == arch_unmap_area) addr = prev ? prev->vm_end : mm->mmap_base; diff --git a/mm/nommu.c b/mm/nommu.c index 9876fa0c3ad..ebb3154d84e 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -608,7 +608,7 @@ static void protect_vma(struct vm_area_struct *vma, unsigned long flags) */ static void add_vma_to_mm(struct mm_struct *mm, struct vm_area_struct *vma) { - struct vm_area_struct *pvma, **pp; + struct vm_area_struct *pvma, **pp, *next; struct address_space *mapping; struct rb_node **p, *parent; @@ -668,8 +668,11 @@ static void add_vma_to_mm(struct mm_struct *mm, struct vm_area_struct *vma) break; } - vma->vm_next = *pp; + next = *pp; *pp = vma; + vma->vm_next = next; + if (next) + next->vm_prev = vma; } /* |