Staging: vme: llseek support in user driver

Provide vme_user_llseek() implementation.

Signed-off-by: Arthur Benilov <arthur.benilov@iba-group.com>
Signed-off-by: Vincent Bossier <vincent.bossier@iba-group.com>
Acked-by: Martyn Welch <martyn.welch@ge.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Arthur Benilov 2010-02-16 15:40:30 +01:00 committed by Greg Kroah-Hartman
parent bb9ea89ec8
commit 877de4b486
1 changed files with 33 additions and 2 deletions

View File

@ -400,8 +400,39 @@ static ssize_t vme_user_write(struct file *file, const char *buf, size_t count,
static loff_t vme_user_llseek(struct file *file, loff_t off, int whence)
{
printk(KERN_ERR "Llseek currently incomplete\n");
return -EINVAL;
loff_t absolute = -1;
unsigned int minor = MINOR(file->f_dentry->d_inode->i_rdev);
size_t image_size;
down(&image[minor].sem);
image_size = vme_get_size(image[minor].resource);
switch (whence) {
case SEEK_SET:
absolute = off;
break;
case SEEK_CUR:
absolute = file->f_pos + off;
break;
case SEEK_END:
absolute = image_size + off;
break;
default:
up(&image[minor].sem);
return -EINVAL;
break;
}
if ((absolute < 0) || (absolute >= image_size)) {
up(&image[minor].sem);
return -EINVAL;
}
file->f_pos = absolute;
up(&image[minor].sem);
return absolute;
}
/*