Merge tag 'char-misc-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char / misc driver updates from Greg KH:
 "Here is the big char/misc driver update for 5.11-rc1.

  Continuing the tradition of previous -rc1 pulls, there seems to be
  more and more tiny driver subsystems flowing through this tree.

  Lots of different things, all of which have been in linux-next for a
  while with no reported issues:

   - extcon driver updates

   - habannalab driver updates

   - mei driver updates

   - uio driver updates

   - binder fixes and features added

   - soundwire driver updates

   - mhi bus driver updates

   - phy driver updates

   - coresight driver updates

   - fpga driver updates

   - speakup driver updates

   - slimbus driver updates

   - various small char and misc driver updates"

* tag 'char-misc-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (305 commits)
  extcon: max77693: Fix modalias string
  extcon: fsa9480: Support TI TSU6111 variant
  extcon: fsa9480: Rewrite bindings in YAML and extend
  dt-bindings: extcon: add binding for TUSB320
  extcon: Add driver for TI TUSB320
  slimbus: qcom: fix potential NULL dereference in qcom_slim_prg_slew()
  siox: Make remove callback return void
  siox: Use bus_type functions for probe, remove and shutdown
  spmi: Add driver shutdown support
  spmi: fix some coding style issues at the spmi core
  spmi: get rid of a warning when built with W=1
  uio: uio_hv_generic: use devm_kzalloc() for private data alloc
  uio: uio_fsl_elbc_gpcm: use device-managed allocators
  uio: uio_aec: use devm_kzalloc() for uio_info object
  uio: uio_cif: use devm_kzalloc() for uio_info object
  uio: uio_netx: use devm_kzalloc() for or uio_info object
  uio: uio_mf624: use devm_kzalloc() for uio_info object
  uio: uio_sercos3: use device-managed functions for simple allocs
  uio: uio_dmem_genirq: finalize conversion of probe to devm_ handlers
  uio: uio_dmem_genirq: convert simple allocations to device-managed
  ...

1 files changed, 48 insertions, 0 deletions

diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
index 2f846b7ae8b8..7caf74ad2405 100644
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -696,6 +696,8 @@ static void binder_free_buf_locked(struct binder_alloc *alloc,
 	binder_insert_free_buffer(alloc, buffer);
 }
 
+static void binder_alloc_clear_buf(struct binder_alloc *alloc,
+				   struct binder_buffer *buffer);
 /**
  * binder_alloc_free_buf() - free a binder buffer
  * @alloc:	binder_alloc for this proc
@@ -706,6 +708,18 @@ static void binder_free_buf_locked(struct binder_alloc *alloc,
 void binder_alloc_free_buf(struct binder_alloc *alloc,
 			    struct binder_buffer *buffer)
 {
+	/*
+	 * We could eliminate the call to binder_alloc_clear_buf()
+	 * from binder_alloc_deferred_release() by moving this to
+	 * binder_alloc_free_buf_locked(). However, that could
+	 * increase contention for the alloc mutex if clear_on_free
+	 * is used frequently for large buffers. The mutex is not
+	 * needed for correctness here.
+	 */
+	if (buffer->clear_on_free) {
+		binder_alloc_clear_buf(alloc, buffer);
+		buffer->clear_on_free = false;
+	}
 	mutex_lock(&alloc->mutex);
 	binder_free_buf_locked(alloc, buffer);
 	mutex_unlock(&alloc->mutex);
@@ -802,6 +816,10 @@ void binder_alloc_deferred_release(struct binder_alloc *alloc)
 		/* Transaction should already have been freed */
 		BUG_ON(buffer->transaction);
 
+		if (buffer->clear_on_free) {
+			binder_alloc_clear_buf(alloc, buffer);
+			buffer->clear_on_free = false;
+		}
 		binder_free_buf_locked(alloc, buffer);
 		buffers++;
 	}
@@ -1136,6 +1154,36 @@ static struct page *binder_alloc_get_page(struct binder_alloc *alloc,
 }
 
 /**
+ * binder_alloc_clear_buf() - zero out buffer
+ * @alloc: binder_alloc for this proc
+ * @buffer: binder buffer to be cleared
+ *
+ * memset the given buffer to 0
+ */
+static void binder_alloc_clear_buf(struct binder_alloc *alloc,
+				   struct binder_buffer *buffer)
+{
+	size_t bytes = binder_alloc_buffer_size(alloc, buffer);
+	binder_size_t buffer_offset = 0;
+
+	while (bytes) {
+		unsigned long size;
+		struct page *page;
+		pgoff_t pgoff;
+		void *kptr;
+
+		page = binder_alloc_get_page(alloc, buffer,
+					     buffer_offset, &pgoff);
+		size = min_t(size_t, bytes, PAGE_SIZE - pgoff);
+		kptr = kmap(page) + pgoff;
+		memset(kptr, 0, size);
+		kunmap(page);
+		bytes -= size;
+		buffer_offset += size;
+	}
+}
+
+/**
  * binder_alloc_copy_user_to_buffer() - copy src user to tgt user
  * @alloc: binder_alloc for this proc
  * @buffer: binder buffer to be accessed