diff options
Diffstat (limited to 'mm/ashmem.c')
| -rw-r--r-- | mm/ashmem.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/mm/ashmem.c b/mm/ashmem.c index 230810f9387c..04e886e2c909 100644 --- a/mm/ashmem.c +++ b/mm/ashmem.c @@ -211,6 +211,31 @@ static int ashmem_release(struct inode *ignored, struct file *file) 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 @@ static struct file_operations ashmem_fops = { .owner = THIS_MODULE, .open = ashmem_open, .release = ashmem_release, + .read = ashmem_read, .mmap = ashmem_mmap, .unlocked_ioctl = ashmem_ioctl, .compat_ioctl = ashmem_ioctl, |