fs: export empty_aops

With the ->sync_page() hook gone, we have a few users that
add their own static address_space_operations without any
functions defined.

fs/inode.c already has an empty_aops that it uses for init
purposes. Lets export that and use it in the places where
an otherwise empty aops was defined.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
This commit is contained in:
Jens Axboe 2011-04-05 23:51:48 +02:00
parent 929e27252e
commit 7dcda1c96d
4 changed files with 12 additions and 5 deletions

View file

@ -124,6 +124,14 @@ __cacheline_aligned_in_smp DEFINE_SPINLOCK(inode_wb_list_lock);
*/
static DECLARE_RWSEM(iprune_sem);
/*
* Empty aops. Can be used for the cases where the user does not
* define any of the address_space operations.
*/
const struct address_space_operations empty_aops = {
};
EXPORT_SYMBOL(empty_aops);
/*
* Statistics gathering..
*/
@ -176,7 +184,6 @@ int proc_nr_inodes(ctl_table *table, int write,
*/
int inode_init_always(struct super_block *sb, struct inode *inode)
{
static const struct address_space_operations empty_aops;
static const struct inode_operations empty_iops;
static const struct file_operations empty_fops;
struct address_space *const mapping = &inode->i_data;

View file

@ -495,8 +495,6 @@ unsigned nilfs_page_count_clean_buffers(struct page *page,
void nilfs_mapping_init(struct address_space *mapping,
struct backing_dev_info *bdi)
{
static const struct address_space_operations empty_aops;
mapping->host = NULL;
mapping->flags = 0;
mapping_set_gfp_mask(mapping, GFP_NOFS);

View file

@ -56,6 +56,7 @@
*/
#include "ubifs.h"
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/xattr.h>
#include <linux/posix_acl_xattr.h>
@ -80,7 +81,6 @@ enum {
};
static const struct inode_operations none_inode_operations;
static const struct address_space_operations none_address_operations;
static const struct file_operations none_file_operations;
/**
@ -130,7 +130,7 @@ static int create_xattr(struct ubifs_info *c, struct inode *host,
}
/* Re-define all operations to be "nothing" */
inode->i_mapping->a_ops = &none_address_operations;
inode->i_mapping->a_ops = &empty_aops;
inode->i_op = &none_inode_operations;
inode->i_fop = &none_file_operations;

View file

@ -613,6 +613,8 @@ struct address_space_operations {
int (*error_remove_page)(struct address_space *, struct page *);
};
extern const struct address_space_operations empty_aops;
/*
* pagecache_write_begin/pagecache_write_end must be used by general code
* to write into the pagecache.