141 строка
4.0 KiB
C
141 строка
4.0 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/* NFS FS-Cache index structure definition
|
|
*
|
|
* Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*/
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/nfs_fs.h>
|
|
#include <linux/nfs_fs_sb.h>
|
|
#include <linux/in6.h>
|
|
#include <linux/iversion.h>
|
|
|
|
#include "internal.h"
|
|
#include "fscache.h"
|
|
|
|
#define NFSDBG_FACILITY NFSDBG_FSCACHE
|
|
|
|
/*
|
|
* Define the NFS filesystem for FS-Cache. Upon registration FS-Cache sticks
|
|
* the cookie for the top-level index object for NFS into here. The top-level
|
|
* index can than have other cache objects inserted into it.
|
|
*/
|
|
struct fscache_netfs nfs_fscache_netfs = {
|
|
.name = "nfs",
|
|
.version = 0,
|
|
};
|
|
|
|
/*
|
|
* Register NFS for caching
|
|
*/
|
|
int nfs_fscache_register(void)
|
|
{
|
|
return fscache_register_netfs(&nfs_fscache_netfs);
|
|
}
|
|
|
|
/*
|
|
* Unregister NFS for caching
|
|
*/
|
|
void nfs_fscache_unregister(void)
|
|
{
|
|
fscache_unregister_netfs(&nfs_fscache_netfs);
|
|
}
|
|
|
|
/*
|
|
* Define the server object for FS-Cache. This is used to describe a server
|
|
* object to fscache_acquire_cookie(). It is keyed by the NFS protocol and
|
|
* server address parameters.
|
|
*/
|
|
const struct fscache_cookie_def nfs_fscache_server_index_def = {
|
|
.name = "NFS.server",
|
|
.type = FSCACHE_COOKIE_TYPE_INDEX,
|
|
};
|
|
|
|
/*
|
|
* Define the superblock object for FS-Cache. This is used to describe a
|
|
* superblock object to fscache_acquire_cookie(). It is keyed by all the NFS
|
|
* parameters that might cause a separate superblock.
|
|
*/
|
|
const struct fscache_cookie_def nfs_fscache_super_index_def = {
|
|
.name = "NFS.super",
|
|
.type = FSCACHE_COOKIE_TYPE_INDEX,
|
|
};
|
|
|
|
/*
|
|
* Consult the netfs about the state of an object
|
|
* - This function can be absent if the index carries no state data
|
|
* - The netfs data from the cookie being used as the target is
|
|
* presented, as is the auxiliary data
|
|
*/
|
|
static
|
|
enum fscache_checkaux nfs_fscache_inode_check_aux(void *cookie_netfs_data,
|
|
const void *data,
|
|
uint16_t datalen,
|
|
loff_t object_size)
|
|
{
|
|
struct nfs_fscache_inode_auxdata auxdata;
|
|
struct nfs_inode *nfsi = cookie_netfs_data;
|
|
|
|
if (datalen != sizeof(auxdata))
|
|
return FSCACHE_CHECKAUX_OBSOLETE;
|
|
|
|
memset(&auxdata, 0, sizeof(auxdata));
|
|
auxdata.mtime_sec = nfsi->vfs_inode.i_mtime.tv_sec;
|
|
auxdata.mtime_nsec = nfsi->vfs_inode.i_mtime.tv_nsec;
|
|
auxdata.ctime_sec = nfsi->vfs_inode.i_ctime.tv_sec;
|
|
auxdata.ctime_nsec = nfsi->vfs_inode.i_ctime.tv_nsec;
|
|
|
|
if (NFS_SERVER(&nfsi->vfs_inode)->nfs_client->rpc_ops->version == 4)
|
|
auxdata.change_attr = inode_peek_iversion_raw(&nfsi->vfs_inode);
|
|
|
|
if (memcmp(data, &auxdata, datalen) != 0)
|
|
return FSCACHE_CHECKAUX_OBSOLETE;
|
|
|
|
return FSCACHE_CHECKAUX_OKAY;
|
|
}
|
|
|
|
/*
|
|
* Get an extra reference on a read context.
|
|
* - This function can be absent if the completion function doesn't require a
|
|
* context.
|
|
* - The read context is passed back to NFS in the event that a data read on the
|
|
* cache fails with EIO - in which case the server must be contacted to
|
|
* retrieve the data, which requires the read context for security.
|
|
*/
|
|
static void nfs_fh_get_context(void *cookie_netfs_data, void *context)
|
|
{
|
|
get_nfs_open_context(context);
|
|
}
|
|
|
|
/*
|
|
* Release an extra reference on a read context.
|
|
* - This function can be absent if the completion function doesn't require a
|
|
* context.
|
|
*/
|
|
static void nfs_fh_put_context(void *cookie_netfs_data, void *context)
|
|
{
|
|
if (context)
|
|
put_nfs_open_context(context);
|
|
}
|
|
|
|
/*
|
|
* Define the inode object for FS-Cache. This is used to describe an inode
|
|
* object to fscache_acquire_cookie(). It is keyed by the NFS file handle for
|
|
* an inode.
|
|
*
|
|
* Coherency is managed by comparing the copies of i_size, i_mtime and i_ctime
|
|
* held in the cache auxiliary data for the data storage object with those in
|
|
* the inode struct in memory.
|
|
*/
|
|
const struct fscache_cookie_def nfs_fscache_inode_object_def = {
|
|
.name = "NFS.fh",
|
|
.type = FSCACHE_COOKIE_TYPE_DATAFILE,
|
|
.check_aux = nfs_fscache_inode_check_aux,
|
|
.get_context = nfs_fh_get_context,
|
|
.put_context = nfs_fh_put_context,
|
|
};
|