ieee1394: mark char device files as not seekable

The
  - raw1394   (/dev/raw1394),
  - video1394 (/dev/video1394/*),
  - dv1394    (/dev/dv1394/*)
character device file ABIs do not make any use of lseek(), pread(), or
pwrite().  Therefore use nonseekable_open() and, redundantly, set
file_operations.llseek to no_llseek to remove any doubt whether the BKL-
grabbing default_llseek handler is used.

Although all this is legacy code which should be left in peace until it
is eventually removed (as it is superseded by firewire-core's
<linux/firewire-cdev.h> ABI), this change seems still worth doing to
further minimize the presence of BKL usage in the kernel.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This commit is contained in:
Stefan Richter 2010-04-10 16:47:18 +01:00
parent 3ac26b2ee3
commit 7cfe21aae1
3 changed files with 11 additions and 8 deletions

View file

@ -1824,7 +1824,7 @@ static int dv1394_open(struct inode *inode, struct file *file)
"and will not be available in the new firewire driver stack. "
"Try libraw1394 based programs instead.\n", current->comm);
return 0;
return nonseekable_open(inode, file);
}
@ -2153,17 +2153,18 @@ static struct cdev dv1394_cdev;
static const struct file_operations dv1394_fops=
{
.owner = THIS_MODULE,
.poll = dv1394_poll,
.poll = dv1394_poll,
.unlocked_ioctl = dv1394_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = dv1394_compat_ioctl,
#endif
.mmap = dv1394_mmap,
.open = dv1394_open,
.write = dv1394_write,
.read = dv1394_read,
.write = dv1394_write,
.read = dv1394_read,
.release = dv1394_release,
.fasync = dv1394_fasync,
.fasync = dv1394_fasync,
.llseek = no_llseek,
};

View file

@ -2834,7 +2834,7 @@ static int raw1394_open(struct inode *inode, struct file *file)
file->private_data = fi;
return 0;
return nonseekable_open(inode, file);
}
static int raw1394_release(struct inode *inode, struct file *file)
@ -3035,6 +3035,7 @@ static const struct file_operations raw1394_fops = {
.poll = raw1394_poll,
.open = raw1394_open,
.release = raw1394_release,
.llseek = no_llseek,
};
static int __init init_raw1394(void)

View file

@ -1239,7 +1239,7 @@ static int video1394_open(struct inode *inode, struct file *file)
ctx->current_ctx = NULL;
file->private_data = ctx;
return 0;
return nonseekable_open(inode, file);
}
static int video1394_release(struct inode *inode, struct file *file)
@ -1287,7 +1287,8 @@ static const struct file_operations video1394_fops=
.poll = video1394_poll,
.mmap = video1394_mmap,
.open = video1394_open,
.release = video1394_release
.release = video1394_release,
.llseek = no_llseek,
};
/*** HOTPLUG STUFF **********************************************************/