Revert "android: binder: Disable preemption while holding the global binder lock."

This reverts commit 6fd130fe5ba15d200251d27aabab0bf4c94d8f13.

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 41e6ffac7c79b825a140b1ba2aefb59123eaf927..cfb76f8c1df3a841a558259f4d82751cd27e938d 100644 (file)
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -473,7 +473,6 @@ static inline void binder_lock(struct binder_context *context, const char *tag)
 {
        trace_binder_lock(tag);
        mutex_lock(&context->binder_main_lock);
-       preempt_disable();
        trace_binder_locked(tag);
 }
 
@@ -482,62 +481,8 @@ static inline void binder_unlock(struct binder_context *context,
 {
        trace_binder_unlock(tag);
        mutex_unlock(&context->binder_main_lock);
-       preempt_enable();
-}
-
-static inline void *kzalloc_preempt_disabled(size_t size)
-{
-       void *ptr;
-
-       ptr = kzalloc(size, GFP_NOWAIT);
-       if (ptr)
-               return ptr;
-
-       preempt_enable_no_resched();
-       ptr = kzalloc(size, GFP_KERNEL);
-       preempt_disable();
-
-       return ptr;
-}
-
-static inline long copy_to_user_preempt_disabled(void __user *to, const void *from, long n)
-{
-       long ret;
-
-       preempt_enable_no_resched();
-       ret = copy_to_user(to, from, n);
-       preempt_disable();
-       return ret;
 }
 
-static inline long copy_from_user_preempt_disabled(void *to, const void __user *from, long n)
-{
-       long ret;
-
-       preempt_enable_no_resched();
-       ret = copy_from_user(to, from, n);
-       preempt_disable();
-       return ret;
-}
-
-#define get_user_preempt_disabled(x, ptr)      \
-({                                             \
-       int __ret;                              \
-       preempt_enable_no_resched();            \
-       __ret = get_user(x, ptr);               \
-       preempt_disable();                      \
-       __ret;                                  \
-})
-
-#define put_user_preempt_disabled(x, ptr)      \
-({                                             \
-       int __ret;                              \
-       preempt_enable_no_resched();            \
-       __ret = put_user(x, ptr);               \
-       preempt_disable();                      \
-       __ret;                                  \
-})
-
 static void binder_set_nice(long nice)
 {
        long min_nice;
@@ -671,8 +616,6 @@ static int binder_update_page_range(struct binder_proc *proc, int allocate,
        else
                mm = get_task_mm(proc->tsk);
 
-       preempt_enable_no_resched();
-
        if (mm) {
                down_write(&mm->mmap_sem);
                vma = proc->vma;
@@ -726,9 +669,6 @@ static int binder_update_page_range(struct binder_proc *proc, int allocate,
                up_write(&mm->mmap_sem);
                mmput(mm);
        }
-
-       preempt_disable();
-
        return 0;
 
 free_range:
@@ -751,9 +691,6 @@ err_no_vma:
                up_write(&mm->mmap_sem);
                mmput(mm);
        }
-
-       preempt_disable();
-
        return -ENOMEM;
 }
 
@@ -1022,7 +959,7 @@ static struct binder_node *binder_new_node(struct binder_proc *proc,
                        return NULL;
        }
 
-       node = kzalloc_preempt_disabled(sizeof(*node));
+       node = kzalloc(sizeof(*node), GFP_KERNEL);
        if (node == NULL)
                return NULL;
        binder_stats_created(BINDER_STAT_NODE);
@@ -1166,7 +1103,7 @@ static struct binder_ref *binder_get_ref_for_node(struct binder_proc *proc,
                else
                        return ref;
        }
-       new_ref = kzalloc_preempt_disabled(sizeof(*ref));
+       new_ref = kzalloc(sizeof(*ref), GFP_KERNEL);
        if (new_ref == NULL)
                return NULL;
        binder_stats_created(BINDER_STAT_REF);
@@ -2037,14 +1974,14 @@ static void binder_transaction(struct binder_proc *proc,
        e->to_proc = target_proc->pid;
 
        /* TODO: reuse incoming transaction for reply */
-       t = kzalloc_preempt_disabled(sizeof(*t));
+       t = kzalloc(sizeof(*t), GFP_KERNEL);
        if (t == NULL) {
                return_error = BR_FAILED_REPLY;
                goto err_alloc_t_failed;
        }
        binder_stats_created(BINDER_STAT_TRANSACTION);
 
-       tcomplete = kzalloc_preempt_disabled(sizeof(*tcomplete));
+       tcomplete = kzalloc(sizeof(*tcomplete), GFP_KERNEL);
        if (tcomplete == NULL) {
                return_error = BR_FAILED_REPLY;
                goto err_alloc_tcomplete_failed;
@@ -2105,14 +2042,14 @@ static void binder_transaction(struct binder_proc *proc,
                                      ALIGN(tr->data_size, sizeof(void *)));
        offp = off_start;
 
-       if (copy_from_user_preempt_disabled(t->buffer->data, (const void __user *)(uintptr_t)
+       if (copy_from_user(t->buffer->data, (const void __user *)(uintptr_t)
                           tr->data.ptr.buffer, tr->data_size)) {
                binder_user_error("%d:%d got transaction with invalid data ptr\n",
                                proc->pid, thread->pid);
                return_error = BR_FAILED_REPLY;
                goto err_copy_data_failed;
        }
-       if (copy_from_user_preempt_disabled(offp, (const void __user *)(uintptr_t)
+       if (copy_from_user(offp, (const void __user *)(uintptr_t)
                           tr->data.ptr.offsets, tr->offsets_size)) {
                binder_user_error("%d:%d got transaction with invalid offsets ptr\n",
                                proc->pid, thread->pid);
@@ -2346,7 +2283,7 @@ int binder_thread_write(struct binder_proc *proc,
        void __user *end = buffer + size;
 
        while (ptr < end && thread->return_error == BR_OK) {
-               if (get_user_preempt_disabled(cmd, (uint32_t __user *)ptr))
+               if (get_user(cmd, (uint32_t __user *)ptr))
                        return -EFAULT;
                ptr += sizeof(uint32_t);
                trace_binder_command(cmd);
@@ -2364,7 +2301,7 @@ int binder_thread_write(struct binder_proc *proc,
                        struct binder_ref *ref;
                        const char *debug_string;
 
-                       if (get_user_preempt_disabled(target, (uint32_t __user *)ptr))
+                       if (get_user(target, (uint32_t __user *)ptr))
                                return -EFAULT;
                        ptr += sizeof(uint32_t);
                        if (target == 0 && context->binder_context_mgr_node &&
@@ -2416,10 +2353,10 @@ int binder_thread_write(struct binder_proc *proc,
                        binder_uintptr_t cookie;
                        struct binder_node *node;
 
-                       if (get_user_preempt_disabled(node_ptr, (binder_uintptr_t __user *)ptr))
+                       if (get_user(node_ptr, (binder_uintptr_t __user *)ptr))
                                return -EFAULT;
                        ptr += sizeof(binder_uintptr_t);
-                       if (get_user_preempt_disabled(cookie, (binder_uintptr_t __user *)ptr))
+                       if (get_user(cookie, (binder_uintptr_t __user *)ptr))
                                return -EFAULT;
                        ptr += sizeof(binder_uintptr_t);
                        node = binder_get_node(proc, node_ptr);
@@ -2477,7 +2414,7 @@ int binder_thread_write(struct binder_proc *proc,
                        binder_uintptr_t data_ptr;
                        struct binder_buffer *buffer;
 
-                       if (get_user_preempt_disabled(data_ptr, (binder_uintptr_t __user *)ptr))
+                       if (get_user(data_ptr, (binder_uintptr_t __user *)ptr))
                                return -EFAULT;
                        ptr += sizeof(binder_uintptr_t);
 
@@ -2531,7 +2468,7 @@ int binder_thread_write(struct binder_proc *proc,
                case BC_REPLY: {
                        struct binder_transaction_data tr;
 
-                       if (copy_from_user_preempt_disabled(&tr, ptr, sizeof(tr)))
+                       if (copy_from_user(&tr, ptr, sizeof(tr)))
                                return -EFAULT;
                        ptr += sizeof(tr);
                        binder_transaction(proc, thread, &tr,
@@ -2582,10 +2519,10 @@ int binder_thread_write(struct binder_proc *proc,
                        struct binder_ref *ref;
                        struct binder_ref_death *death;
 
-                       if (get_user_preempt_disabled(target, (uint32_t __user *)ptr))
+                       if (get_user(target, (uint32_t __user *)ptr))
                                return -EFAULT;
                        ptr += sizeof(uint32_t);
-                       if (get_user_preempt_disabled(cookie, (binder_uintptr_t __user *)ptr))
+                       if (get_user(cookie, (binder_uintptr_t __user *)ptr))
                                return -EFAULT;
                        ptr += sizeof(binder_uintptr_t);
                        ref = binder_get_ref(proc, target, false);
@@ -2614,7 +2551,7 @@ int binder_thread_write(struct binder_proc *proc,
                                                proc->pid, thread->pid);
                                        break;
                                }
-                               death = kzalloc_preempt_disabled(sizeof(*death));
+                               death = kzalloc(sizeof(*death), GFP_KERNEL);
                                if (death == NULL) {
                                        thread->return_error = BR_ERROR;
                                        binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
@@ -2669,7 +2606,7 @@ int binder_thread_write(struct binder_proc *proc,
                        binder_uintptr_t cookie;
                        struct binder_ref_death *death = NULL;
 
-                       if (get_user_preempt_disabled(cookie, (binder_uintptr_t __user *)ptr))
+                       if (get_user(cookie, (binder_uintptr_t __user *)ptr))
                                return -EFAULT;
 
                        ptr += sizeof(cookie);
@@ -2750,7 +2687,7 @@ static int binder_thread_read(struct binder_proc *proc,
        int wait_for_proc_work;
 
        if (*consumed == 0) {
-               if (put_user_preempt_disabled(BR_NOOP, (uint32_t __user *)ptr))
+               if (put_user(BR_NOOP, (uint32_t __user *)ptr))
                        return -EFAULT;
                ptr += sizeof(uint32_t);
        }
@@ -2761,7 +2698,7 @@ retry:
 
        if (thread->return_error != BR_OK && ptr < end) {
                if (thread->return_error2 != BR_OK) {
-                       if (put_user_preempt_disabled(thread->return_error2, (uint32_t __user *)ptr))
+                       if (put_user(thread->return_error2, (uint32_t __user *)ptr))
                                return -EFAULT;
                        ptr += sizeof(uint32_t);
                        binder_stat_br(proc, thread, thread->return_error2);
@@ -2769,7 +2706,7 @@ retry:
                                goto done;
                        thread->return_error2 = BR_OK;
                }
-               if (put_user_preempt_disabled(thread->return_error, (uint32_t __user *)ptr))
+               if (put_user(thread->return_error, (uint32_t __user *)ptr))
                        return -EFAULT;
                ptr += sizeof(uint32_t);
                binder_stat_br(proc, thread, thread->return_error);
@@ -2847,7 +2784,7 @@ retry:
                } break;
                case BINDER_WORK_TRANSACTION_COMPLETE: {
                        cmd = BR_TRANSACTION_COMPLETE;
-                       if (put_user_preempt_disabled(cmd, (uint32_t __user *)ptr))
+                       if (put_user(cmd, (uint32_t __user *)ptr))
                                return -EFAULT;
                        ptr += sizeof(uint32_t);
 
@@ -2889,14 +2826,14 @@ retry:
                                node->has_weak_ref = 0;
                        }
                        if (cmd != BR_NOOP) {
-                               if (put_user_preempt_disabled(cmd, (uint32_t __user *)ptr))
+                               if (put_user(cmd, (uint32_t __user *)ptr))
                                        return -EFAULT;
                                ptr += sizeof(uint32_t);
-                               if (put_user_preempt_disabled(node->ptr,
+                               if (put_user(node->ptr,
                                             (binder_uintptr_t __user *)ptr))
                                        return -EFAULT;
                                ptr += sizeof(binder_uintptr_t);
-                               if (put_user_preempt_disabled(node->cookie,
+                               if (put_user(node->cookie,
                                             (binder_uintptr_t __user *)ptr))
                                        return -EFAULT;
                                ptr += sizeof(binder_uintptr_t);
@@ -2940,10 +2877,10 @@ retry:
                                cmd = BR_CLEAR_DEATH_NOTIFICATION_DONE;
                        else
                                cmd = BR_DEAD_BINDER;
-                       if (put_user_preempt_disabled(cmd, (uint32_t __user *)ptr))
+                       if (put_user(cmd, (uint32_t __user *)ptr))
                                return -EFAULT;
                        ptr += sizeof(uint32_t);
-                       if (put_user_preempt_disabled(death->cookie,
+                       if (put_user(death->cookie,
                                     (binder_uintptr_t __user *)ptr))
                                return -EFAULT;
                        ptr += sizeof(binder_uintptr_t);
@@ -3011,10 +2948,10 @@ retry:
                                        ALIGN(t->buffer->data_size,
                                            sizeof(void *));
 
-               if (put_user_preempt_disabled(cmd, (uint32_t __user *)ptr))
+               if (put_user(cmd, (uint32_t __user *)ptr))
                        return -EFAULT;
                ptr += sizeof(uint32_t);
-               if (copy_to_user_preempt_disabled(ptr, &tr, sizeof(tr)))
+               if (copy_to_user(ptr, &tr, sizeof(tr)))
                        return -EFAULT;
                ptr += sizeof(tr);
 
@@ -3056,7 +2993,7 @@ done:
                binder_debug(BINDER_DEBUG_THREADS,
                             "%d:%d BR_SPAWN_LOOPER\n",
                             proc->pid, thread->pid);
-               if (put_user_preempt_disabled(BR_SPAWN_LOOPER, (uint32_t __user *)buffer))
+               if (put_user(BR_SPAWN_LOOPER, (uint32_t __user *)buffer))
                        return -EFAULT;
                binder_stat_br(proc, thread, BR_SPAWN_LOOPER);
        }
@@ -3131,7 +3068,7 @@ static struct binder_thread *binder_get_thread(struct binder_proc *proc)
                        break;
        }
        if (*p == NULL) {
-               thread = kzalloc_preempt_disabled(sizeof(*thread));
+               thread = kzalloc(sizeof(*thread), GFP_KERNEL);
                if (thread == NULL)
                        return NULL;
                binder_stats_created(BINDER_STAT_THREAD);
@@ -3235,7 +3172,7 @@ static int binder_ioctl_write_read(struct file *filp,
                ret = -EINVAL;
                goto out;
        }
-       if (copy_from_user_preempt_disabled(&bwr, ubuf, sizeof(bwr))) {
+       if (copy_from_user(&bwr, ubuf, sizeof(bwr))) {
                ret = -EFAULT;
                goto out;
        }
@@ -3253,7 +3190,7 @@ static int binder_ioctl_write_read(struct file *filp,
                trace_binder_write_done(ret);
                if (ret < 0) {
                        bwr.read_consumed = 0;
-                       if (copy_to_user_preempt_disabled(ubuf, &bwr, sizeof(bwr)))
+                       if (copy_to_user(ubuf, &bwr, sizeof(bwr)))
                                ret = -EFAULT;
                        goto out;
                }
@@ -3267,7 +3204,7 @@ static int binder_ioctl_write_read(struct file *filp,
                if (!list_empty(&proc->todo))
                        wake_up_interruptible(&proc->wait);
                if (ret < 0) {
-                       if (copy_to_user_preempt_disabled(ubuf, &bwr, sizeof(bwr)))
+                       if (copy_to_user(ubuf, &bwr, sizeof(bwr)))
                                ret = -EFAULT;
                        goto out;
                }
@@ -3277,7 +3214,7 @@ static int binder_ioctl_write_read(struct file *filp,
                     proc->pid, thread->pid,
                     (u64)bwr.write_consumed, (u64)bwr.write_size,
                     (u64)bwr.read_consumed, (u64)bwr.read_size);
-       if (copy_to_user_preempt_disabled(ubuf, &bwr, sizeof(bwr))) {
+       if (copy_to_user(ubuf, &bwr, sizeof(bwr))) {
                ret = -EFAULT;
                goto out;
        }
@@ -3358,7 +3295,7 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
                        goto err;
                break;
        case BINDER_SET_MAX_THREADS:
-               if (copy_from_user_preempt_disabled(&proc->max_threads, ubuf, sizeof(proc->max_threads))) {
+               if (copy_from_user(&proc->max_threads, ubuf, sizeof(proc->max_threads))) {
                        ret = -EINVAL;
                        goto err;
                }
@@ -3381,8 +3318,7 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
                        ret = -EINVAL;
                        goto err;
                }
-
-               if (put_user_preempt_disabled(BINDER_CURRENT_PROTOCOL_VERSION,
+               if (put_user(BINDER_CURRENT_PROTOCOL_VERSION,
                             &ver->protocol_version)) {
                        ret = -EINVAL;
                        goto err;
@@ -3445,7 +3381,6 @@ static struct vm_operations_struct binder_vm_ops = {
 static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
 {
        int ret;
-
        struct vm_struct *area;
        struct binder_proc *proc = filp->private_data;
        const char *failure_string;
@@ -3506,11 +3441,7 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
        vma->vm_ops = &binder_vm_ops;
        vma->vm_private_data = proc;
 
-       /* binder_update_page_range assumes preemption is disabled */
-       preempt_disable();
-       ret = binder_update_page_range(proc, 1, proc->buffer, proc->buffer + PAGE_SIZE, vma);
-       preempt_enable_no_resched();
-       if (ret) {
+       if (binder_update_page_range(proc, 1, proc->buffer, proc->buffer + PAGE_SIZE, vma)) {
                ret = -ENOMEM;
                failure_string = "alloc small buf";
                goto err_alloc_small_buf_failed;
@@ -3799,12 +3730,8 @@ static void binder_deferred_func(struct work_struct *work)
        int defer;
 
        do {
-               trace_binder_lock(__func__);
-               mutex_lock(&context->binder_main_lock);
-               trace_binder_locked(__func__);
-
+               binder_lock(__func__);
                mutex_lock(&context->binder_deferred_lock);
-               preempt_disable();
                if (!hlist_empty(&context->binder_deferred_list)) {
                        proc = hlist_entry(context->binder_deferred_list.first,
                                           struct binder_proc,
@@ -3831,9 +3758,7 @@ static void binder_deferred_func(struct work_struct *work)
                if (defer & BINDER_DEFERRED_RELEASE)
                        binder_deferred_release(proc); /* frees proc */
 
-               trace_binder_unlock(__func__);
-               mutex_unlock(&context->binder_main_lock);
-               preempt_enable_no_resched();
+               binder_unlock(__func__);
                if (files)
                        put_files_struct(files);
        } while (proc);