diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c index 51b502217d00..f555eebceef6 100644 --- a/drivers/android/binder_alloc.c +++ b/drivers/android/binder_alloc.c @@ -213,7 +213,7 @@ static int binder_update_page_range(struct binder_alloc *alloc, int allocate, if (mm) { mmap_read_lock(mm); - vma = alloc->vma; + vma = vma_lookup(mm, alloc->vma_addr); } if (!vma && need_mm) { @@ -313,16 +313,15 @@ err_no_vma: static inline void binder_alloc_set_vma(struct binder_alloc *alloc, struct vm_area_struct *vma) { - if (vma) + unsigned long vm_start = 0; + + if (vma) { + vm_start = vma->vm_start; alloc->vma_vm_mm = vma->vm_mm; - /* - * If we see alloc->vma is not NULL, buffer data structures set up - * completely. Look at smp_rmb side binder_alloc_get_vma. - * We also want to guarantee new alloc->vma_vm_mm is always visible - * if alloc->vma is set. - */ - smp_wmb(); - alloc->vma = vma; + } + + mmap_assert_write_locked(alloc->vma_vm_mm); + alloc->vma_addr = vm_start; } static inline struct vm_area_struct *binder_alloc_get_vma( @@ -330,11 +329,9 @@ static inline struct vm_area_struct *binder_alloc_get_vma( { struct vm_area_struct *vma = NULL; - if (alloc->vma) { - /* Look at description in binder_alloc_set_vma */ - smp_rmb(); - vma = alloc->vma; - } + if (alloc->vma_addr) + vma = vma_lookup(alloc->vma_vm_mm, alloc->vma_addr); + return vma; } @@ -817,7 +814,8 @@ void binder_alloc_deferred_release(struct binder_alloc *alloc) buffers = 0; mutex_lock(&alloc->mutex); - BUG_ON(alloc->vma); + BUG_ON(alloc->vma_addr && + vma_lookup(alloc->vma_vm_mm, alloc->vma_addr)); while ((n = rb_first(&alloc->allocated_buffers))) { buffer = rb_entry(n, struct binder_buffer, rb_node); diff --git a/drivers/android/binder_alloc.h b/drivers/android/binder_alloc.h index 7dea57a84c79..1e4fd37af5e0 100644 --- a/drivers/android/binder_alloc.h +++ b/drivers/android/binder_alloc.h @@ -100,7 +100,7 @@ struct binder_lru_page { */ struct binder_alloc { struct mutex mutex; - struct vm_area_struct *vma; + unsigned long vma_addr; struct mm_struct *vma_vm_mm; void __user *buffer; struct list_head buffers; diff --git a/drivers/android/binder_alloc_selftest.c b/drivers/android/binder_alloc_selftest.c index c2b323bc3b3a..43a881073a42 100644 --- a/drivers/android/binder_alloc_selftest.c +++ b/drivers/android/binder_alloc_selftest.c @@ -287,7 +287,7 @@ void binder_selftest_alloc(struct binder_alloc *alloc) if (!binder_selftest_run) return; mutex_lock(&binder_selftest_lock); - if (!binder_selftest_run || !alloc->vma) + if (!binder_selftest_run || !alloc->vma_addr) goto done; pr_info("STARTED\n"); binder_selftest_alloc_offset(alloc, end_offset, 0);