1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* AFS fileserver list management.
4 * Copyright (C) 2017 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
8 #include <linux/kernel.h>
9 #include <linux/slab.h>
12 void afs_put_serverlist(struct afs_net *net, struct afs_server_list *slist)
16 if (slist && refcount_dec_and_test(&slist->usage)) {
17 for (i = 0; i < slist->nr_servers; i++) {
18 afs_put_cb_interest(net, slist->servers[i].cb_interest);
19 afs_unuse_server(net, slist->servers[i].server,
20 afs_server_trace_put_slist);
27 * Build a server list from a VLDB record.
29 struct afs_server_list *afs_alloc_server_list(struct afs_cell *cell,
31 struct afs_vldb_entry *vldb,
34 struct afs_server_list *slist;
35 struct afs_server *server;
36 int ret = -ENOMEM, nr_servers = 0, i, j;
38 for (i = 0; i < vldb->nr_servers; i++)
39 if (vldb->fs_mask[i] & type_mask)
42 slist = kzalloc(struct_size(slist, servers, nr_servers), GFP_KERNEL);
46 refcount_set(&slist->usage, 1);
47 rwlock_init(&slist->lock);
49 for (i = 0; i < AFS_MAXTYPES; i++)
50 slist->vids[i] = vldb->vid[i];
52 /* Make sure a records exists for each server in the list. */
53 for (i = 0; i < vldb->nr_servers; i++) {
54 if (!(vldb->fs_mask[i] & type_mask))
57 server = afs_lookup_server(cell, key, &vldb->fs_server[i],
58 vldb->addr_version[i]);
60 ret = PTR_ERR(server);
67 /* Insertion-sort by UUID */
68 for (j = 0; j < slist->nr_servers; j++)
69 if (memcmp(&slist->servers[j].server->uuid,
71 sizeof(server->uuid)) >= 0)
73 if (j < slist->nr_servers) {
74 if (slist->servers[j].server == server) {
75 afs_put_server(cell->net, server,
76 afs_server_trace_put_slist_isort);
80 memmove(slist->servers + j + 1,
82 (slist->nr_servers - j) * sizeof(struct afs_server_entry));
85 slist->servers[j].server = server;
89 if (slist->nr_servers == 0) {
97 afs_put_serverlist(cell->net, slist);
103 * Copy the annotations from an old server list to its potential replacement.
105 bool afs_annotate_server_list(struct afs_server_list *new,
106 struct afs_server_list *old)
108 struct afs_server *cur;
111 if (old->nr_servers != new->nr_servers)
114 for (i = 0; i < old->nr_servers; i++)
115 if (old->servers[i].server != new->servers[i].server)
121 /* Maintain the same preferred server as before if possible. */
122 cur = old->servers[old->preferred].server;
123 for (j = 0; j < new->nr_servers; j++) {
124 if (new->servers[j].server == cur) {
130 /* Keep the old callback interest records where possible so that we
131 * maintain callback interception.
135 while (i < old->nr_servers && j < new->nr_servers) {
136 if (new->servers[j].server == old->servers[i].server) {
137 struct afs_cb_interest *cbi = old->servers[i].cb_interest;
139 new->servers[j].cb_interest = cbi;
140 refcount_inc(&cbi->usage);
147 if (new->servers[j].server < old->servers[i].server) {