Implement read(2) in ashmem driver
Bug: 2595601
Change-Id: I47c0016f594f9354fb8658ccb26e3d395bcb137b
Signed-off-by: Bjorn Bringert <bringert@android.com>
diff --git a/mm/ashmem.c b/mm/ashmem.c
index 230810f..04e886e 100644
--- a/mm/ashmem.c
+++ b/mm/ashmem.c
@@ -211,6 +211,31 @@
return 0;
}
+static ssize_t ashmem_read(struct file *file, char __user *buf,
+ size_t len, loff_t *pos)
+{
+ struct ashmem_area *asma = file->private_data;
+ int ret = 0;
+
+ mutex_lock(&ashmem_mutex);
+
+ /* If size is not set, or set to 0, always return EOF. */
+ if (asma->size == 0) {
+ goto out;
+ }
+
+ if (!asma->file) {
+ ret = -EBADF;
+ goto out;
+ }
+
+ ret = asma->file->f_op->read(asma->file, buf, len, pos);
+
+out:
+ mutex_unlock(&ashmem_mutex);
+ return ret;
+}
+
static int ashmem_mmap(struct file *file, struct vm_area_struct *vma)
{
struct ashmem_area *asma = file->private_data;
@@ -604,6 +629,7 @@
.owner = THIS_MODULE,
.open = ashmem_open,
.release = ashmem_release,
+ .read = ashmem_read,
.mmap = ashmem_mmap,
.unlocked_ioctl = ashmem_ioctl,
.compat_ioctl = ashmem_ioctl,