On Tue, Sep 17, 2013 at 10:18:25AM -0400, Benjamin LaHaise wrote:
> +static int aio_set_page_dirty(struct page *page)
> +{
> +     return 0;
> +};
> +
> +static const struct address_space_operations aio_aops = {
> +     .set_page_dirty = aio_set_page_dirty,
> +};
> +
> +/*
> + * A single inode exists for each aio_inode file.  The inodes are only
> + * used for mapping the event ring buffers in order to make it possible
> + * to provide migration ops to the vm.
> + */
> +static struct inode *aio_inode_mkinode(struct super_block *s)
> +{
> +     struct inode *inode = new_inode_pseudo(s);
> +
> +     if (!inode)
> +             return ERR_PTR(-ENOMEM);
> +
> +     inode->i_ino = get_next_ino();
> +     inode->i_fop = &aio_ring_fops;
> +     inode->i_mapping->a_ops = &aio_aops;
> +
> +     /*
> +      * Mark the inode dirty from the very beginning,
> +      * that way it will never be moved to the dirty
> +      * list because mark_inode_dirty() will think
> +      * that it already _is_ on the dirty list.
> +      */
> +     inode->i_state = I_DIRTY;
> +     inode->i_mode = S_IRUSR | S_IWUSR;
> +     inode->i_uid = current_fsuid();
> +     inode->i_gid = current_fsgid();
> +     inode->i_flags |= S_PRIVATE;
> +     inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
> +     return inode;
> +}

FWIW, I would've taken that to fs/libfs.c, sans the assignment of ->i_fop.
BTW, are you sure that you want it to be opened via procfs symlink?  Is that
even possible?  IOW, what's that ->i_fop for?

> +struct file *aio_inode_getfile_private(const char *name,
> +                                    const struct file_operations *fops,
> +                                    void *priv, int flags)

Why is it not static?  And why bother with fops as argument, etc.?

> +     if (fops->owner && !try_module_get(fops->owner))
> +             return ERR_PTR(-ENOENT);

Also pointless, AFAICS.  BTW, you've just open-coded fops_get(fops), not
that it mattered in this case...

> +     inode = aio_inode_mkinode(aio_mnt->mnt_sb);
> +     if (IS_ERR(inode)) {
> +             file = ERR_PTR(-ENOMEM);
> +             goto err_module;
> +     }
> +
> +     /*
> +      * Link the inode to a directory entry by creating a unique name
> +      * using the inode sequence number.
> +      */
> +     file = ERR_PTR(-ENOMEM);
> +     this.name = name;
> +     this.len = strlen(name);
> +     this.hash = 0;

Umm...  ITYM
        struct qstr this = QSTR_INIT("[aio]", 5);
, if not
        path.dentry = d_alloc_pseudo(aio_mnt->mnt_sb,
                                     &(struct qstr)QSTR_INIT("[aio]", 5));
> +     if (!path.dentry)
> +             goto err_module;
> +
> +     path.mnt = mntget(aio_mnt);
> +
> +     d_instantiate(path.dentry, inode);
> +
> +     file = alloc_file(&path, OPEN_FMODE(flags), fops);
> +     if (IS_ERR(file))
> +             goto err_dput;

> +     file->f_mapping = inode->i_mapping;

Pointless, BTW - alloc_file() will have already set it that way.

> +     file->f_flags = flags & (O_ACCMODE | O_NONBLOCK);
> +     file->private_data = priv;
> +
> +     return file;
> +
> +err_dput:
> +     path_put(&path);
> +err_module:
> +     module_put(fops->owner);

And that module_put is pointless as well here.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to