alistair23-linux/fs/afs/main.c
David Howells 0da0b7fd73 afs: Display manually added cells in dynamic root mount
Alter the dynroot mount so that cells created by manipulation of
/proc/fs/afs/cells and /proc/fs/afs/rootcell and by specification of a root
cell as a module parameter will cause directories for those cells to be
created in the dynamic root superblock for the network namespace[*].

To this end:

 (1) Only one dynamic root superblock is now created per network namespace
     and this is shared between all attempts to mount it.  This makes it
     easier to find the superblock to modify.

 (2) When a dynamic root superblock is created, the list of cells is walked
     and directories created for each cell already defined.

 (3) When a new cell is added, if a dynamic root superblock exists, a
     directory is created for it.

 (4) When a cell is destroyed, the directory is removed.

 (5) These directories are created by calling lookup_one_len() on the root
     dir which automatically creates them if they don't exist.

[*] Inasmuch as network namespaces are currently supported here.

Signed-off-by: David Howells <dhowells@redhat.com>
2018-06-15 15:27:09 +01:00

256 lines
6.3 KiB
C

/* AFS client file system
*
* Copyright (C) 2002,5 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 License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/completion.h>
#include <linux/sched.h>
#include <linux/random.h>
#include <linux/proc_fs.h>
#define CREATE_TRACE_POINTS
#include "internal.h"
MODULE_DESCRIPTION("AFS Client File System");
MODULE_AUTHOR("Red Hat, Inc.");
MODULE_LICENSE("GPL");
unsigned afs_debug;
module_param_named(debug, afs_debug, uint, S_IWUSR | S_IRUGO);
MODULE_PARM_DESC(debug, "AFS debugging mask");
static char *rootcell;
module_param(rootcell, charp, 0);
MODULE_PARM_DESC(rootcell, "root AFS cell name and VL server IP addr list");
struct workqueue_struct *afs_wq;
static struct proc_dir_entry *afs_proc_symlink;
#if defined(CONFIG_ALPHA)
const char afs_init_sysname[] = "alpha_linux26";
#elif defined(CONFIG_X86_64)
const char afs_init_sysname[] = "amd64_linux26";
#elif defined(CONFIG_ARM)
const char afs_init_sysname[] = "arm_linux26";
#elif defined(CONFIG_ARM64)
const char afs_init_sysname[] = "aarch64_linux26";
#elif defined(CONFIG_X86_32)
const char afs_init_sysname[] = "i386_linux26";
#elif defined(CONFIG_IA64)
const char afs_init_sysname[] = "ia64_linux26";
#elif defined(CONFIG_PPC64)
const char afs_init_sysname[] = "ppc64_linux26";
#elif defined(CONFIG_PPC32)
const char afs_init_sysname[] = "ppc_linux26";
#elif defined(CONFIG_S390)
#ifdef CONFIG_64BIT
const char afs_init_sysname[] = "s390x_linux26";
#else
const char afs_init_sysname[] = "s390_linux26";
#endif
#elif defined(CONFIG_SPARC64)
const char afs_init_sysname[] = "sparc64_linux26";
#elif defined(CONFIG_SPARC32)
const char afs_init_sysname[] = "sparc_linux26";
#else
const char afs_init_sysname[] = "unknown_linux26";
#endif
/*
* Initialise an AFS network namespace record.
*/
static int __net_init afs_net_init(struct net *net_ns)
{
struct afs_sysnames *sysnames;
struct afs_net *net = afs_net(net_ns);
int ret;
net->net = net_ns;
net->live = true;
generate_random_uuid((unsigned char *)&net->uuid);
INIT_WORK(&net->charge_preallocation_work, afs_charge_preallocation);
mutex_init(&net->socket_mutex);
net->cells = RB_ROOT;
seqlock_init(&net->cells_lock);
INIT_WORK(&net->cells_manager, afs_manage_cells);
timer_setup(&net->cells_timer, afs_cells_timer, 0);
mutex_init(&net->proc_cells_lock);
INIT_LIST_HEAD(&net->proc_cells);
seqlock_init(&net->fs_lock);
net->fs_servers = RB_ROOT;
INIT_LIST_HEAD(&net->fs_updates);
INIT_HLIST_HEAD(&net->fs_proc);
INIT_HLIST_HEAD(&net->fs_addresses4);
INIT_HLIST_HEAD(&net->fs_addresses6);
seqlock_init(&net->fs_addr_lock);
INIT_WORK(&net->fs_manager, afs_manage_servers);
timer_setup(&net->fs_timer, afs_servers_timer, 0);
ret = -ENOMEM;
sysnames = kzalloc(sizeof(*sysnames), GFP_KERNEL);
if (!sysnames)
goto error_sysnames;
sysnames->subs[0] = (char *)&afs_init_sysname;
sysnames->nr = 1;
refcount_set(&sysnames->usage, 1);
net->sysnames = sysnames;
rwlock_init(&net->sysnames_lock);
/* Register the /proc stuff */
ret = afs_proc_init(net);
if (ret < 0)
goto error_proc;
/* Initialise the cell DB */
ret = afs_cell_init(net, rootcell);
if (ret < 0)
goto error_cell_init;
/* Create the RxRPC transport */
ret = afs_open_socket(net);
if (ret < 0)
goto error_open_socket;
return 0;
error_open_socket:
net->live = false;
afs_cell_purge(net);
afs_purge_servers(net);
error_cell_init:
net->live = false;
afs_proc_cleanup(net);
error_proc:
afs_put_sysnames(net->sysnames);
error_sysnames:
net->live = false;
return ret;
}
/*
* Clean up and destroy an AFS network namespace record.
*/
static void __net_exit afs_net_exit(struct net *net_ns)
{
struct afs_net *net = afs_net(net_ns);
net->live = false;
afs_cell_purge(net);
afs_purge_servers(net);
afs_close_socket(net);
afs_proc_cleanup(net);
afs_put_sysnames(net->sysnames);
}
static struct pernet_operations afs_net_ops = {
.init = afs_net_init,
.exit = afs_net_exit,
.id = &afs_net_id,
.size = sizeof(struct afs_net),
};
/*
* initialise the AFS client FS module
*/
static int __init afs_init(void)
{
int ret = -ENOMEM;
printk(KERN_INFO "kAFS: Red Hat AFS client v0.1 registering.\n");
afs_wq = alloc_workqueue("afs", 0, 0);
if (!afs_wq)
goto error_afs_wq;
afs_async_calls = alloc_workqueue("kafsd", WQ_MEM_RECLAIM, 0);
if (!afs_async_calls)
goto error_async;
afs_lock_manager = alloc_workqueue("kafs_lockd", WQ_MEM_RECLAIM, 0);
if (!afs_lock_manager)
goto error_lockmgr;
#ifdef CONFIG_AFS_FSCACHE
/* we want to be able to cache */
ret = fscache_register_netfs(&afs_cache_netfs);
if (ret < 0)
goto error_cache;
#endif
ret = register_pernet_subsys(&afs_net_ops);
if (ret < 0)
goto error_net;
/* register the filesystems */
ret = afs_fs_init();
if (ret < 0)
goto error_fs;
afs_proc_symlink = proc_symlink("fs/afs", NULL, "../self/net/afs");
if (IS_ERR(afs_proc_symlink)) {
ret = PTR_ERR(afs_proc_symlink);
goto error_proc;
}
return ret;
error_proc:
afs_fs_exit();
error_fs:
unregister_pernet_subsys(&afs_net_ops);
error_net:
#ifdef CONFIG_AFS_FSCACHE
fscache_unregister_netfs(&afs_cache_netfs);
error_cache:
#endif
destroy_workqueue(afs_lock_manager);
error_lockmgr:
destroy_workqueue(afs_async_calls);
error_async:
destroy_workqueue(afs_wq);
error_afs_wq:
rcu_barrier();
printk(KERN_ERR "kAFS: failed to register: %d\n", ret);
return ret;
}
/* XXX late_initcall is kludgy, but the only alternative seems to create
* a transport upon the first mount, which is worse. Or is it?
*/
late_initcall(afs_init); /* must be called after net/ to create socket */
/*
* clean up on module removal
*/
static void __exit afs_exit(void)
{
printk(KERN_INFO "kAFS: Red Hat AFS client v0.1 unregistering.\n");
proc_remove(afs_proc_symlink);
afs_fs_exit();
unregister_pernet_subsys(&afs_net_ops);
#ifdef CONFIG_AFS_FSCACHE
fscache_unregister_netfs(&afs_cache_netfs);
#endif
destroy_workqueue(afs_lock_manager);
destroy_workqueue(afs_async_calls);
destroy_workqueue(afs_wq);
afs_clean_up_permit_cache();
rcu_barrier();
}
module_exit(afs_exit);