Support lseek(2) in ashmem driver
Signed-off-by: Bjorn Bringert <bringert@android.com>
Change-Id: I509d18b21832e229737ea7ebaa231fb107eb61d7
diff --git a/mm/ashmem.c b/mm/ashmem.c
index b6c5e2a..f92eb34 100644
--- a/mm/ashmem.c
+++ b/mm/ashmem.c
@@ -178,7 +178,7 @@
struct ashmem_area *asma;
int ret;
- ret = nonseekable_open(inode, file);
+ ret = generic_file_open(inode, file);
if (unlikely(ret))
return ret;
@@ -230,6 +230,42 @@
}
ret = asma->file->f_op->read(asma->file, buf, len, pos);
+ if (ret < 0) {
+ goto out;
+ }
+
+ /** Update backing file pos, since f_ops->read() doesn't */
+ asma->file->f_pos = *pos;
+
+out:
+ mutex_unlock(&ashmem_mutex);
+ return ret;
+}
+
+static loff_t ashmem_llseek(struct file *file, loff_t offset, int origin)
+{
+ struct ashmem_area *asma = file->private_data;
+ int ret;
+
+ mutex_lock(&ashmem_mutex);
+
+ if (asma->size == 0) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (!asma->file) {
+ ret = -EBADF;
+ goto out;
+ }
+
+ ret = asma->file->f_op->llseek(asma->file, offset, origin);
+ if (ret < 0) {
+ goto out;
+ }
+
+ /** Copy f_pos from backing file, since f_ops->llseek() sets it */
+ file->f_pos = asma->file->f_pos;
out:
mutex_unlock(&ashmem_mutex);
@@ -640,6 +676,7 @@
.open = ashmem_open,
.release = ashmem_release,
.read = ashmem_read,
+ .llseek = ashmem_llseek,
.mmap = ashmem_mmap,
.unlocked_ioctl = ashmem_ioctl,
.compat_ioctl = ashmem_ioctl,