lkml.org 
[lkml]   [2012]   [Oct]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [patch 05/10] vfs: pass data to alloc_inode super operation
On Tue, Oct 30, 2012 at 08:51:42PM +0000, Al Viro wrote:
> On Tue, Oct 30, 2012 at 04:14:39PM -0400, Jeff Moyer wrote:
> > This patch passes a data pointer along to the alloc_inode
> > super_operations function. The value will initially be used by
> > bdev_alloc_inode to allocate the bdev_inode on the same numa
> > node as the device to which it is tied.
>
> Yecchhh...
>
> > -static struct inode *bdev_alloc_inode(struct super_block *sb)
> > +static struct inode *bdev_alloc_inode(struct super_block *sb, void *data)
> > {
> > - struct bdev_inode *ei = kmem_cache_alloc(bdev_cachep, GFP_KERNEL);
> > + struct bdev_inode *ei;
> > + int partno;
> > + int node;
> > +
> > + if (data) {
> > + struct gendisk *disk;
> > + dev_t dev = *(dev_t *)data;
> > + disk = get_gendisk(dev, &partno);
> > + node = disk->node_id;

BTW, speaking of other reasons this is FUBAR - mknod a block device node
for something that doesn't exist and try to open it. struct block_device
lifetime is not limited to that of struct gendisk; it can be allocated
before gendisk is there. Moreover, with static /dev and demand-loaded
modules this will be the normal scenario.

IOW, this is completely misguided.


\
 
 \ /
  Last update: 2012-10-30 22:41    [W:0.100 / U:0.404 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site