Merge tag 'asoc-v5.0' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus

ASoC: Updates for v5.0/v4.20

As ever there's a lot of small and driver specific changes going on
here, but we do also have some relatively large changes in the core
thanks to the hard work of Charles and Morimoto-san:

 - More component transitions from Morimoto-san, I think we're about
   finished with this.  Thanks for all the hard work!
 - Morimoto-san also added a bunch of for_each_foo macros
 - A bunch of cleanups and fixes for DAPM from Charles.
 - MCLK support for several different devices, including CS42L51, STM32
   SAI, and MAX98373.
 - Support for Allwinner A64 CODEC analog, Intel boards with DA7219 and
   MAX98927, Meson AXG PDM inputs, Nuvoton NAU8822, Renesas R8A7744 and
   TI PCM3060.

1 files changed, 35 insertions, 8 deletions

diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
index 3f3b7b253445..64fd96eada31 100644
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -332,6 +332,35 @@ err_no_vma:
 	return vma ? -ENOMEM : -ESRCH;
 }
 
+
+static inline void binder_alloc_set_vma(struct binder_alloc *alloc,
+		struct vm_area_struct *vma)
+{
+	if (vma)
+		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;
+}
+
+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;
+}
+
 static struct binder_buffer *binder_alloc_new_buf_locked(
 				struct binder_alloc *alloc,
 				size_t data_size,
@@ -348,7 +377,7 @@ static struct binder_buffer *binder_alloc_new_buf_locked(
 	size_t size, data_offsets_size;
 	int ret;
 
-	if (alloc->vma == NULL) {
+	if (!binder_alloc_get_vma(alloc)) {
 		binder_alloc_debug(BINDER_DEBUG_USER_ERROR,
 				   "%d: binder_alloc_buf, no vma\n",
 				   alloc->pid);
@@ -723,9 +752,7 @@ 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;
-	barrier();
-	alloc->vma = vma;
-	alloc->vma_vm_mm = vma->vm_mm;
+	binder_alloc_set_vma(alloc, vma);
 	mmgrab(alloc->vma_vm_mm);
 
 	return 0;
@@ -754,10 +781,10 @@ void binder_alloc_deferred_release(struct binder_alloc *alloc)
 	int buffers, page_count;
 	struct binder_buffer *buffer;
 
-	BUG_ON(alloc->vma);
-
 	buffers = 0;
 	mutex_lock(&alloc->mutex);
+	BUG_ON(alloc->vma);
+
 	while ((n = rb_first(&alloc->allocated_buffers))) {
 		buffer = rb_entry(n, struct binder_buffer, rb_node);
 
@@ -900,7 +927,7 @@ int binder_alloc_get_allocated_count(struct binder_alloc *alloc)
  */
 void binder_alloc_vma_close(struct binder_alloc *alloc)
 {
-	WRITE_ONCE(alloc->vma, NULL);
+	binder_alloc_set_vma(alloc, NULL);
 }
 
 /**
@@ -935,7 +962,7 @@ enum lru_status binder_alloc_free_page(struct list_head *item,
 
 	index = page - alloc->pages;
 	page_addr = (uintptr_t)alloc->buffer + index * PAGE_SIZE;
-	vma = alloc->vma;
+	vma = binder_alloc_get_vma(alloc);
 	if (vma) {
 		if (!mmget_not_zero(alloc->vma_vm_mm))
 			goto err_mmget;