diff options
| author | spkal01 <kalligeross@gmail.com> | 2021-05-17 02:37:28 +0530 |
|---|---|---|
| committer | spkal01 <kalligeross@gmail.com> | 2021-05-17 02:37:28 +0530 |
| commit | 93b265ae2eba8d93d0ffa406958547232f3114c8 (patch) | |
| tree | c2f093aa144f732b5cf7bd8a0b45bf35eda42e1c /drivers/android/binder.c | |
| parent | 0a82617b8fce8994076b518064e7d420af290ea8 (diff) | |
| parent | 016f4ba70bffb6d02725e778c3989fa542e6d12a (diff) | |
Diffstat (limited to 'drivers/android/binder.c')
| -rw-r--r-- | drivers/android/binder.c | 212 |
1 files changed, 200 insertions, 12 deletions
diff --git a/drivers/android/binder.c b/drivers/android/binder.c index afb4675d65f3..632308c48bf7 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -459,9 +459,19 @@ struct binder_priority { * (protected by binder_deferred_lock) * @deferred_work: bitmap of deferred work to perform * (protected by binder_deferred_lock) + * @outstanding_txns: number of transactions to be transmitted before + * processes in freeze_wait are woken up + * (protected by @inner_lock) * @is_dead: process is dead and awaiting free * when outstanding transactions are cleaned up * (protected by @inner_lock) + * @sync_recv: process received sync transactions since last frozen + * (protected by @inner_lock) + * @async_recv: process received async transactions since last frozen + * (protected by @inner_lock) + * @freeze_wait: waitqueue of processes waiting for all outstanding + * transactions to be processed + * (protected by @inner_lock) * @todo: list of work for this process * (protected by @inner_lock) * @stats: per-process binder statistics @@ -505,7 +515,12 @@ struct binder_proc { struct mutex files_lock; struct hlist_node deferred_work_node; int deferred_work; + int outstanding_txns; bool is_dead; + bool is_frozen; + bool sync_recv; + bool async_recv; + wait_queue_head_t freeze_wait; struct list_head todo; struct binder_stats stats; @@ -2076,6 +2091,10 @@ static void binder_free_transaction(struct binder_transaction *t) spin_unlock(&t->lock); binder_inner_proc_lock(target_proc); + target_proc->outstanding_txns--; + BUG_ON(target_proc->outstanding_txns < 0); + if (!target_proc->outstanding_txns && target_proc->is_frozen) + wake_up_interruptible_all(&target_proc->freeze_wait); if (t->buffer) t->buffer->transaction = NULL; binder_inner_proc_unlock(target_proc); @@ -2829,10 +2848,11 @@ static int binder_fixup_parent(struct binder_transaction *t, * If the @thread parameter is not NULL, the transaction is always queued * to the waitlist of that specific thread. * - * Return: true if the transactions was successfully queued - * false if the target process or thread is dead + * Return: 0 if the transaction was successfully queued + * BR_DEAD_REPLY if the target process or thread is dead + * BR_FROZEN_REPLY if the target process or thread is frozen */ -static bool binder_proc_transaction(struct binder_transaction *t, +static int binder_proc_transaction(struct binder_transaction *t, struct binder_proc *proc, struct binder_thread *thread) { @@ -2856,11 +2876,18 @@ static bool binder_proc_transaction(struct binder_transaction *t, } binder_inner_proc_lock(proc); + if (proc->is_frozen) { + proc->sync_recv |= !oneway; + proc->async_recv |= oneway; + } - if (proc->is_dead || (thread && thread->is_dead)) { + if ((proc->is_frozen && !oneway) || proc->is_dead || + (thread && thread->is_dead)) { + bool proc_is_dead = proc->is_dead + || (thread && thread->is_dead); binder_inner_proc_unlock(proc); binder_node_unlock(node); - return false; + return proc_is_dead ? BR_DEAD_REPLY : BR_FROZEN_REPLY; } if (!thread && !pending_async) @@ -2879,10 +2906,11 @@ static bool binder_proc_transaction(struct binder_transaction *t, if (!pending_async) binder_wakeup_thread_ilocked(proc, thread, !oneway /* sync */); + proc->outstanding_txns++; binder_inner_proc_unlock(proc); binder_node_unlock(node); - return true; + return 0; } /** @@ -3203,7 +3231,7 @@ static void binder_transaction(struct binder_proc *proc, t->buffer = binder_alloc_new_buf(&target_proc->alloc, tr->data_size, tr->offsets_size, extra_buffers_size, - !reply && (t->flags & TF_ONE_WAY)); + !reply && (t->flags & TF_ONE_WAY), current->tgid); if (IS_ERR(t->buffer)) { /* * -ESRCH indicates VMA cleared. The target is dying. @@ -3231,6 +3259,7 @@ static void binder_transaction(struct binder_proc *proc, t->buffer->debug_id = t->debug_id; t->buffer->transaction = t; t->buffer->target_node = target_node; + t->buffer->clear_on_free = !!(t->flags & TF_CLEAR_BUF); trace_binder_transaction_alloc_buf(t->buffer); if (binder_alloc_copy_user_to_buffer( @@ -3476,13 +3505,16 @@ static void binder_transaction(struct binder_proc *proc, if (reply) { binder_enqueue_thread_work(thread, tcomplete); binder_inner_proc_lock(target_proc); - if (target_thread->is_dead) { + if (target_thread->is_dead || target_proc->is_frozen) { + return_error = target_thread->is_dead ? + BR_DEAD_REPLY : BR_FROZEN_REPLY; binder_inner_proc_unlock(target_proc); goto err_dead_proc_or_thread; } BUG_ON(t->buffer->async_transaction != 0); binder_pop_transaction_ilocked(target_thread, in_reply_to); binder_enqueue_thread_work_ilocked(target_thread, &t->work); + target_proc->outstanding_txns++; binder_inner_proc_unlock(target_proc); wake_up_interruptible_sync(&target_thread->wait); binder_restore_priority(current, in_reply_to->saved_priority); @@ -3502,7 +3534,9 @@ static void binder_transaction(struct binder_proc *proc, t->from_parent = thread->transaction_stack; thread->transaction_stack = t; binder_inner_proc_unlock(proc); - if (!binder_proc_transaction(t, target_proc, target_thread)) { + return_error = binder_proc_transaction(t, + target_proc, target_thread); + if (return_error) { binder_inner_proc_lock(proc); binder_pop_transaction_ilocked(thread, t); binder_inner_proc_unlock(proc); @@ -3512,7 +3546,8 @@ static void binder_transaction(struct binder_proc *proc, BUG_ON(target_node == NULL); BUG_ON(t->buffer->async_transaction != 1); binder_enqueue_thread_work(thread, tcomplete); - if (!binder_proc_transaction(t, target_proc, NULL)) + return_error = binder_proc_transaction(t, target_proc, NULL); + if (return_error) goto err_dead_proc_or_thread; } if (target_thread) @@ -3529,7 +3564,6 @@ static void binder_transaction(struct binder_proc *proc, return; err_dead_proc_or_thread: - return_error = BR_DEAD_REPLY; return_error_line = __LINE__; binder_dequeue_work(proc, tcomplete); err_translate_failed: @@ -4134,7 +4168,7 @@ static int binder_wait_for_work(struct binder_thread *thread, binder_inner_proc_lock(proc); list_del_init(&thread->waiting_thread_node); if (signal_pending(current)) { - ret = -ERESTARTSYS; + ret = -EINTR; break; } } @@ -4638,6 +4672,7 @@ static void binder_free_proc(struct binder_proc *proc) BUG_ON(!list_empty(&proc->todo)); BUG_ON(!list_empty(&proc->delivered_death)); + WARN_ON(proc->outstanding_txns); device = container_of(proc->context, struct binder_device, context); if (refcount_dec_and_test(&device->ref)) { kfree(proc->context->name); @@ -4698,6 +4733,7 @@ static int binder_thread_release(struct binder_proc *proc, (t->to_thread == thread) ? "in" : "out"); if (t->to_thread == thread) { + t->to_proc->outstanding_txns--; t->to_proc = NULL; t->to_thread = NULL; if (t->buffer) { @@ -4944,6 +4980,76 @@ static int binder_ioctl_get_node_debug_info(struct binder_proc *proc, return 0; } +static int binder_ioctl_freeze(struct binder_freeze_info *info, + struct binder_proc *target_proc) +{ + int ret = 0; + + if (!info->enable) { + binder_inner_proc_lock(target_proc); + target_proc->sync_recv = false; + target_proc->async_recv = false; + target_proc->is_frozen = false; + binder_inner_proc_unlock(target_proc); + return 0; + } + + /* + * Freezing the target. Prevent new transactions by + * setting frozen state. If timeout specified, wait + * for transactions to drain. + */ + binder_inner_proc_lock(target_proc); + target_proc->sync_recv = false; + target_proc->async_recv = false; + target_proc->is_frozen = true; + binder_inner_proc_unlock(target_proc); + + if (info->timeout_ms > 0) + ret = wait_event_interruptible_timeout( + target_proc->freeze_wait, + (!target_proc->outstanding_txns), + msecs_to_jiffies(info->timeout_ms)); + + if (!ret && target_proc->outstanding_txns) + ret = -EAGAIN; + + if (ret < 0) { + binder_inner_proc_lock(target_proc); + target_proc->is_frozen = false; + binder_inner_proc_unlock(target_proc); + } + + return ret; +} + +static int binder_ioctl_get_freezer_info( + struct binder_frozen_status_info *info) +{ + struct binder_proc *target_proc; + bool found = false; + + info->sync_recv = 0; + info->async_recv = 0; + + mutex_lock(&binder_procs_lock); + hlist_for_each_entry(target_proc, &binder_procs, proc_node) { + if (target_proc->pid == info->pid) { + found = true; + binder_inner_proc_lock(target_proc); + info->sync_recv |= target_proc->sync_recv; + info->async_recv |= target_proc->async_recv; + binder_inner_proc_unlock(target_proc); + } + } + mutex_unlock(&binder_procs_lock); + + if (!found) + return -EINVAL; + + return 0; +} + static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { int ret; @@ -5062,6 +5168,84 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) } break; } + case BINDER_FREEZE: { + struct binder_freeze_info info; + struct binder_proc **target_procs = NULL, *target_proc; + int target_procs_count = 0, i = 0; + + ret = 0; + + if (copy_from_user(&info, ubuf, sizeof(info))) { + ret = -EFAULT; + goto err; + } + + mutex_lock(&binder_procs_lock); + hlist_for_each_entry(target_proc, &binder_procs, proc_node) { + if (target_proc->pid == info.pid) + target_procs_count++; + } + + if (target_procs_count == 0) { + mutex_unlock(&binder_procs_lock); + ret = -EINVAL; + goto err; + } + + target_procs = kmalloc(sizeof(struct binder_proc *) * + target_procs_count, + GFP_KERNEL); + + if (!target_procs) { + mutex_unlock(&binder_procs_lock); + ret = -ENOMEM; + goto err; + } + + hlist_for_each_entry(target_proc, &binder_procs, proc_node) { + if (target_proc->pid != info.pid) + continue; + + binder_inner_proc_lock(target_proc); + atomic_inc(&target_proc->tmp_ref); + binder_inner_proc_unlock(target_proc); + + target_procs[i++] = target_proc; + } + mutex_unlock(&binder_procs_lock); + + for (i = 0; i < target_procs_count; i++) { + if (ret >= 0) + ret = binder_ioctl_freeze(&info, + target_procs[i]); + + binder_proc_dec_tmpref(target_procs[i]); + } + + kfree(target_procs); + + if (ret < 0) + goto err; + break; + } + case BINDER_GET_FROZEN_INFO: { + struct binder_frozen_status_info info; + + if (copy_from_user(&info, ubuf, sizeof(info))) { + ret = -EFAULT; + goto err; + } + + ret = binder_ioctl_get_freezer_info(&info); + if (ret < 0) + goto err; + + if (copy_to_user(ubuf, &info, sizeof(info))) { + ret = -EFAULT; + goto err; + } + break; + } default: ret = -EINVAL; goto err; @@ -5176,6 +5360,7 @@ static int binder_open(struct inode *nodp, struct file *filp) proc->tsk = current->group_leader; mutex_init(&proc->files_lock); INIT_LIST_HEAD(&proc->todo); + init_waitqueue_head(&proc->freeze_wait); if (binder_supported_policy(current->policy)) { proc->default_priority.sched_policy = current->policy; proc->default_priority.prio = current->normal_prio; @@ -5397,6 +5582,9 @@ static void binder_deferred_release(struct binder_proc *proc) atomic_inc(&proc->tmp_ref); proc->is_dead = true; + proc->is_frozen = false; + proc->sync_recv = false; + proc->async_recv = false; threads = 0; active_transactions = 0; while ((n = rb_first(&proc->threads))) { |
