// SPDX-License-Identifier: GPL-2.0-or-later
|
/* AFS fileserver list management.
|
*
|
* Copyright (C) 2017 Red Hat, Inc. All Rights Reserved.
|
* Written by David Howells (dhowells@redhat.com)
|
*/
|
|
#include <linux/kernel.h>
|
#include <linux/slab.h>
|
#include "internal.h"
|
|
void afs_put_serverlist(struct afs_net *net, struct afs_server_list *slist)
|
{
|
int i;
|
|
if (slist && refcount_dec_and_test(&slist->usage)) {
|
for (i = 0; i < slist->nr_servers; i++)
|
afs_unuse_server(net, slist->servers[i].server,
|
afs_server_trace_put_slist);
|
kfree(slist);
|
}
|
}
|
|
/*
|
* Build a server list from a VLDB record.
|
*/
|
struct afs_server_list *afs_alloc_server_list(struct afs_cell *cell,
|
struct key *key,
|
struct afs_vldb_entry *vldb,
|
u8 type_mask)
|
{
|
struct afs_server_list *slist;
|
struct afs_server *server;
|
int ret = -ENOMEM, nr_servers = 0, i, j;
|
|
for (i = 0; i < vldb->nr_servers; i++)
|
if (vldb->fs_mask[i] & type_mask)
|
nr_servers++;
|
|
slist = kzalloc(struct_size(slist, servers, nr_servers), GFP_KERNEL);
|
if (!slist)
|
goto error;
|
|
refcount_set(&slist->usage, 1);
|
rwlock_init(&slist->lock);
|
|
for (i = 0; i < AFS_MAXTYPES; i++)
|
slist->vids[i] = vldb->vid[i];
|
|
/* Make sure a records exists for each server in the list. */
|
for (i = 0; i < vldb->nr_servers; i++) {
|
if (!(vldb->fs_mask[i] & type_mask))
|
continue;
|
|
server = afs_lookup_server(cell, key, &vldb->fs_server[i],
|
vldb->addr_version[i]);
|
if (IS_ERR(server)) {
|
ret = PTR_ERR(server);
|
if (ret == -ENOENT ||
|
ret == -ENOMEDIUM)
|
continue;
|
goto error_2;
|
}
|
|
/* Insertion-sort by UUID */
|
for (j = 0; j < slist->nr_servers; j++)
|
if (memcmp(&slist->servers[j].server->uuid,
|
&server->uuid,
|
sizeof(server->uuid)) >= 0)
|
break;
|
if (j < slist->nr_servers) {
|
if (slist->servers[j].server == server) {
|
afs_put_server(cell->net, server,
|
afs_server_trace_put_slist_isort);
|
continue;
|
}
|
|
memmove(slist->servers + j + 1,
|
slist->servers + j,
|
(slist->nr_servers - j) * sizeof(struct afs_server_entry));
|
}
|
|
slist->servers[j].server = server;
|
slist->nr_servers++;
|
}
|
|
if (slist->nr_servers == 0) {
|
ret = -EDESTADDRREQ;
|
goto error_2;
|
}
|
|
return slist;
|
|
error_2:
|
afs_put_serverlist(cell->net, slist);
|
error:
|
return ERR_PTR(ret);
|
}
|
|
/*
|
* Copy the annotations from an old server list to its potential replacement.
|
*/
|
bool afs_annotate_server_list(struct afs_server_list *new,
|
struct afs_server_list *old)
|
{
|
struct afs_server *cur;
|
int i, j;
|
|
if (old->nr_servers != new->nr_servers)
|
goto changed;
|
|
for (i = 0; i < old->nr_servers; i++)
|
if (old->servers[i].server != new->servers[i].server)
|
goto changed;
|
|
return false;
|
|
changed:
|
/* Maintain the same preferred server as before if possible. */
|
cur = old->servers[old->preferred].server;
|
for (j = 0; j < new->nr_servers; j++) {
|
if (new->servers[j].server == cur) {
|
new->preferred = j;
|
break;
|
}
|
}
|
|
return true;
|
}
|
