From 877de4b4866f1cc0a25a4d67d3927304556f5d1f Mon Sep 17 00:00:00 2001 From: Arthur Benilov Date: Tue, 16 Feb 2010 15:40:30 +0100 Subject: [PATCH] Staging: vme: llseek support in user driver Provide vme_user_llseek() implementation. Signed-off-by: Arthur Benilov Signed-off-by: Vincent Bossier Acked-by: Martyn Welch Signed-off-by: Greg Kroah-Hartman --- drivers/staging/vme/devices/vme_user.c | 35 ++++++++++++++++++++++++-- 1 file changed, 33 insertions(+), 2 deletions(-) diff --git a/drivers/staging/vme/devices/vme_user.c b/drivers/staging/vme/devices/vme_user.c index 48d46cadb13f..ddecbe5105b9 100644 --- a/drivers/staging/vme/devices/vme_user.c +++ b/drivers/staging/vme/devices/vme_user.c @@ -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; } /* -- 2.34.1