mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-11-24 23:00:53 +07:00
b130ed5998
Only override netfs->primary_index when registering success. Cc: stable@vger.kernel.org # v2.6.30+ Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
103 lines
2.5 KiB
C
103 lines
2.5 KiB
C
/* FS-Cache netfs (client) registration
|
|
*
|
|
* Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public Licence
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the Licence, or (at your option) any later version.
|
|
*/
|
|
|
|
#define FSCACHE_DEBUG_LEVEL COOKIE
|
|
#include <linux/module.h>
|
|
#include <linux/slab.h>
|
|
#include "internal.h"
|
|
|
|
static LIST_HEAD(fscache_netfs_list);
|
|
|
|
/*
|
|
* register a network filesystem for caching
|
|
*/
|
|
int __fscache_register_netfs(struct fscache_netfs *netfs)
|
|
{
|
|
struct fscache_netfs *ptr;
|
|
struct fscache_cookie *cookie;
|
|
int ret;
|
|
|
|
_enter("{%s}", netfs->name);
|
|
|
|
INIT_LIST_HEAD(&netfs->link);
|
|
|
|
/* allocate a cookie for the primary index */
|
|
cookie = kmem_cache_zalloc(fscache_cookie_jar, GFP_KERNEL);
|
|
|
|
if (!cookie) {
|
|
_leave(" = -ENOMEM");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* initialise the primary index cookie */
|
|
atomic_set(&cookie->usage, 1);
|
|
atomic_set(&cookie->n_children, 0);
|
|
atomic_set(&cookie->n_active, 1);
|
|
|
|
cookie->def = &fscache_fsdef_netfs_def;
|
|
cookie->parent = &fscache_fsdef_index;
|
|
cookie->netfs_data = netfs;
|
|
cookie->flags = 1 << FSCACHE_COOKIE_ENABLED;
|
|
|
|
spin_lock_init(&cookie->lock);
|
|
INIT_HLIST_HEAD(&cookie->backing_objects);
|
|
|
|
/* check the netfs type is not already present */
|
|
down_write(&fscache_addremove_sem);
|
|
|
|
ret = -EEXIST;
|
|
list_for_each_entry(ptr, &fscache_netfs_list, link) {
|
|
if (strcmp(ptr->name, netfs->name) == 0)
|
|
goto already_registered;
|
|
}
|
|
|
|
atomic_inc(&cookie->parent->usage);
|
|
atomic_inc(&cookie->parent->n_children);
|
|
|
|
netfs->primary_index = cookie;
|
|
list_add(&netfs->link, &fscache_netfs_list);
|
|
ret = 0;
|
|
|
|
pr_notice("Netfs '%s' registered for caching\n", netfs->name);
|
|
|
|
already_registered:
|
|
up_write(&fscache_addremove_sem);
|
|
|
|
if (ret < 0)
|
|
kmem_cache_free(fscache_cookie_jar, cookie);
|
|
|
|
_leave(" = %d", ret);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(__fscache_register_netfs);
|
|
|
|
/*
|
|
* unregister a network filesystem from the cache
|
|
* - all cookies must have been released first
|
|
*/
|
|
void __fscache_unregister_netfs(struct fscache_netfs *netfs)
|
|
{
|
|
_enter("{%s.%u}", netfs->name, netfs->version);
|
|
|
|
down_write(&fscache_addremove_sem);
|
|
|
|
list_del(&netfs->link);
|
|
fscache_relinquish_cookie(netfs->primary_index, 0);
|
|
|
|
up_write(&fscache_addremove_sem);
|
|
|
|
pr_notice("Netfs '%s' unregistered from caching\n",
|
|
netfs->name);
|
|
|
|
_leave("");
|
|
}
|
|
EXPORT_SYMBOL(__fscache_unregister_netfs);
|