diff options
| -rw-r--r-- | drivers/android/binder_alloc.c | 22 |
1 files changed, 7 insertions, 15 deletions
diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c index 3cfad638db63..a54deddafc6d 100644 --- a/drivers/android/binder_alloc.c +++ b/drivers/android/binder_alloc.c @@ -309,29 +309,18 @@ err_no_vma: return vma ? -ENOMEM : -ESRCH; } - static inline void binder_alloc_set_vma(struct binder_alloc *alloc, struct vm_area_struct *vma) { - /* - * If we see alloc->vma is not NULL, buffer data structures set up - * completely. Look at smp_rmb side binder_alloc_get_vma. - */ - smp_wmb(); - alloc->vma = vma; + /* pairs with smp_load_acquire in binder_alloc_get_vma() */ + smp_store_release(&alloc->vma, vma); } static inline struct vm_area_struct *binder_alloc_get_vma( struct binder_alloc *alloc) { - struct vm_area_struct *vma = NULL; - - if (alloc->vma) { - /* Look at description in binder_alloc_set_vma */ - smp_rmb(); - vma = alloc->vma; - } - return vma; + /* pairs with smp_store_release in binder_alloc_set_vma() */ + return smp_load_acquire(&alloc->vma); } static bool debug_low_async_space_locked(struct binder_alloc *alloc, int pid) @@ -394,6 +383,7 @@ static struct binder_buffer *binder_alloc_new_buf_locked( size_t size, data_offsets_size; int ret; + /* Check binder_alloc is fully initialized */ if (!binder_alloc_get_vma(alloc)) { binder_alloc_debug(BINDER_DEBUG_USER_ERROR, "%d: binder_alloc_buf, no vma\n", @@ -789,6 +779,8 @@ int binder_alloc_mmap_handler(struct binder_alloc *alloc, buffer->free = 1; binder_insert_free_buffer(alloc, buffer); alloc->free_async_space = alloc->buffer_size / 2; + + /* Signal binder_alloc is fully initialized */ binder_alloc_set_vma(alloc, vma); return 0; |