![David Howells](/assets/img/avatar_default.png)
When a cell with a volume location server list is added manually by
echoing the details into /proc/net/afs/cells, a record is added but the
flag saying it has been looked up isn't set.
This causes the VL server rotation code to wait forever, with the top of
/proc/pid/stack looking like:
afs_select_vlserver+0x3a6/0x6f3
afs_vl_lookup_vldb+0x4b/0x92
afs_create_volume+0x25/0x1b9
...
with the thread stuck in afs_start_vl_iteration() waiting for
AFS_CELL_FL_NO_LOOKUP_YET to be cleared.
Fix this by clearing AFS_CELL_FL_NO_LOOKUP_YET when setting up a record
if that record's details were supplied manually.
Fixes: 0a5143f2f8
("afs: Implement VL server rotation")
Reported-by: Dave Botsch <dwb7@cornell.edu>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
812 lines
20 KiB
C
812 lines
20 KiB
C
/* AFS cell and server record management
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*
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* Copyright (C) 2002, 2017 Red Hat, Inc. All Rights Reserved.
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* Written by David Howells (dhowells@redhat.com)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/slab.h>
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#include <linux/key.h>
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#include <linux/ctype.h>
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#include <linux/dns_resolver.h>
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#include <linux/sched.h>
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#include <linux/inet.h>
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#include <linux/namei.h>
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#include <keys/rxrpc-type.h>
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#include "internal.h"
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static unsigned __read_mostly afs_cell_gc_delay = 10;
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static unsigned __read_mostly afs_cell_min_ttl = 10 * 60;
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static unsigned __read_mostly afs_cell_max_ttl = 24 * 60 * 60;
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static void afs_manage_cell(struct work_struct *);
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static void afs_dec_cells_outstanding(struct afs_net *net)
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{
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if (atomic_dec_and_test(&net->cells_outstanding))
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wake_up_var(&net->cells_outstanding);
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}
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/*
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* Set the cell timer to fire after a given delay, assuming it's not already
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* set for an earlier time.
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*/
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static void afs_set_cell_timer(struct afs_net *net, time64_t delay)
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{
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if (net->live) {
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atomic_inc(&net->cells_outstanding);
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if (timer_reduce(&net->cells_timer, jiffies + delay * HZ))
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afs_dec_cells_outstanding(net);
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}
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}
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/*
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* Look up and get an activation reference on a cell record under RCU
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* conditions. The caller must hold the RCU read lock.
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*/
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struct afs_cell *afs_lookup_cell_rcu(struct afs_net *net,
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const char *name, unsigned int namesz)
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{
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struct afs_cell *cell = NULL;
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struct rb_node *p;
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int n, seq = 0, ret = 0;
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_enter("%*.*s", namesz, namesz, name);
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if (name && namesz == 0)
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return ERR_PTR(-EINVAL);
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if (namesz > AFS_MAXCELLNAME)
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return ERR_PTR(-ENAMETOOLONG);
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do {
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/* Unfortunately, rbtree walking doesn't give reliable results
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* under just the RCU read lock, so we have to check for
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* changes.
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*/
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if (cell)
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afs_put_cell(net, cell);
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cell = NULL;
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ret = -ENOENT;
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read_seqbegin_or_lock(&net->cells_lock, &seq);
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if (!name) {
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cell = rcu_dereference_raw(net->ws_cell);
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if (cell) {
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afs_get_cell(cell);
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break;
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}
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ret = -EDESTADDRREQ;
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continue;
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}
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p = rcu_dereference_raw(net->cells.rb_node);
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while (p) {
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cell = rb_entry(p, struct afs_cell, net_node);
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n = strncasecmp(cell->name, name,
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min_t(size_t, cell->name_len, namesz));
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if (n == 0)
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n = cell->name_len - namesz;
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if (n < 0) {
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p = rcu_dereference_raw(p->rb_left);
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} else if (n > 0) {
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p = rcu_dereference_raw(p->rb_right);
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} else {
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if (atomic_inc_not_zero(&cell->usage)) {
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ret = 0;
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break;
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}
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/* We want to repeat the search, this time with
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* the lock properly locked.
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*/
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}
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cell = NULL;
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}
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} while (need_seqretry(&net->cells_lock, seq));
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done_seqretry(&net->cells_lock, seq);
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return ret == 0 ? cell : ERR_PTR(ret);
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}
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/*
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* Set up a cell record and fill in its name, VL server address list and
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* allocate an anonymous key
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*/
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static struct afs_cell *afs_alloc_cell(struct afs_net *net,
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const char *name, unsigned int namelen,
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const char *addresses)
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{
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struct afs_cell *cell;
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int i, ret;
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ASSERT(name);
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if (namelen == 0)
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return ERR_PTR(-EINVAL);
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if (namelen > AFS_MAXCELLNAME) {
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_leave(" = -ENAMETOOLONG");
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return ERR_PTR(-ENAMETOOLONG);
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}
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if (namelen == 5 && memcmp(name, "@cell", 5) == 0)
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return ERR_PTR(-EINVAL);
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_enter("%*.*s,%s", namelen, namelen, name, addresses);
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cell = kzalloc(sizeof(struct afs_cell), GFP_KERNEL);
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if (!cell) {
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_leave(" = -ENOMEM");
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return ERR_PTR(-ENOMEM);
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}
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cell->net = net;
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cell->name_len = namelen;
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for (i = 0; i < namelen; i++)
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cell->name[i] = tolower(name[i]);
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atomic_set(&cell->usage, 2);
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INIT_WORK(&cell->manager, afs_manage_cell);
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cell->flags = ((1 << AFS_CELL_FL_NOT_READY) |
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(1 << AFS_CELL_FL_NO_LOOKUP_YET));
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INIT_LIST_HEAD(&cell->proc_volumes);
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rwlock_init(&cell->proc_lock);
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rwlock_init(&cell->vl_servers_lock);
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/* Fill in the VL server list if we were given a list of addresses to
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* use.
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*/
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if (addresses) {
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struct afs_vlserver_list *vllist;
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vllist = afs_parse_text_addrs(net,
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addresses, strlen(addresses), ':',
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VL_SERVICE, AFS_VL_PORT);
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if (IS_ERR(vllist)) {
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ret = PTR_ERR(vllist);
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goto parse_failed;
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}
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rcu_assign_pointer(cell->vl_servers, vllist);
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cell->dns_expiry = TIME64_MAX;
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__clear_bit(AFS_CELL_FL_NO_LOOKUP_YET, &cell->flags);
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} else {
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cell->dns_expiry = ktime_get_real_seconds();
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}
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_leave(" = %p", cell);
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return cell;
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parse_failed:
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if (ret == -EINVAL)
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printk(KERN_ERR "kAFS: bad VL server IP address\n");
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kfree(cell);
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_leave(" = %d", ret);
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return ERR_PTR(ret);
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}
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/*
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* afs_lookup_cell - Look up or create a cell record.
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* @net: The network namespace
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* @name: The name of the cell.
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* @namesz: The strlen of the cell name.
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* @vllist: A colon/comma separated list of numeric IP addresses or NULL.
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* @excl: T if an error should be given if the cell name already exists.
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*
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* Look up a cell record by name and query the DNS for VL server addresses if
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* needed. Note that that actual DNS query is punted off to the manager thread
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* so that this function can return immediately if interrupted whilst allowing
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* cell records to be shared even if not yet fully constructed.
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*/
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struct afs_cell *afs_lookup_cell(struct afs_net *net,
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const char *name, unsigned int namesz,
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const char *vllist, bool excl)
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{
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struct afs_cell *cell, *candidate, *cursor;
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struct rb_node *parent, **pp;
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int ret, n;
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_enter("%s,%s", name, vllist);
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if (!excl) {
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rcu_read_lock();
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cell = afs_lookup_cell_rcu(net, name, namesz);
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rcu_read_unlock();
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if (!IS_ERR(cell))
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goto wait_for_cell;
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}
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/* Assume we're probably going to create a cell and preallocate and
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* mostly set up a candidate record. We can then use this to stash the
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* name, the net namespace and VL server addresses.
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*
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* We also want to do this before we hold any locks as it may involve
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* upcalling to userspace to make DNS queries.
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*/
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candidate = afs_alloc_cell(net, name, namesz, vllist);
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if (IS_ERR(candidate)) {
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_leave(" = %ld", PTR_ERR(candidate));
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return candidate;
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}
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/* Find the insertion point and check to see if someone else added a
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* cell whilst we were allocating.
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*/
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write_seqlock(&net->cells_lock);
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pp = &net->cells.rb_node;
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parent = NULL;
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while (*pp) {
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parent = *pp;
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cursor = rb_entry(parent, struct afs_cell, net_node);
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n = strncasecmp(cursor->name, name,
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min_t(size_t, cursor->name_len, namesz));
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if (n == 0)
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n = cursor->name_len - namesz;
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if (n < 0)
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pp = &(*pp)->rb_left;
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else if (n > 0)
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pp = &(*pp)->rb_right;
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else
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goto cell_already_exists;
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}
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cell = candidate;
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candidate = NULL;
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rb_link_node_rcu(&cell->net_node, parent, pp);
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rb_insert_color(&cell->net_node, &net->cells);
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atomic_inc(&net->cells_outstanding);
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write_sequnlock(&net->cells_lock);
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queue_work(afs_wq, &cell->manager);
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wait_for_cell:
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_debug("wait_for_cell");
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ret = wait_on_bit(&cell->flags, AFS_CELL_FL_NOT_READY, TASK_INTERRUPTIBLE);
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smp_rmb();
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switch (READ_ONCE(cell->state)) {
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case AFS_CELL_FAILED:
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ret = cell->error;
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goto error;
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default:
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_debug("weird %u %d", cell->state, cell->error);
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goto error;
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case AFS_CELL_ACTIVE:
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break;
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}
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_leave(" = %p [cell]", cell);
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return cell;
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cell_already_exists:
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_debug("cell exists");
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cell = cursor;
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if (excl) {
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ret = -EEXIST;
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} else {
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afs_get_cell(cursor);
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ret = 0;
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}
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write_sequnlock(&net->cells_lock);
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kfree(candidate);
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if (ret == 0)
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goto wait_for_cell;
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goto error_noput;
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error:
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afs_put_cell(net, cell);
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error_noput:
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_leave(" = %d [error]", ret);
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return ERR_PTR(ret);
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}
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/*
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* set the root cell information
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* - can be called with a module parameter string
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* - can be called from a write to /proc/fs/afs/rootcell
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*/
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int afs_cell_init(struct afs_net *net, const char *rootcell)
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{
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struct afs_cell *old_root, *new_root;
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const char *cp, *vllist;
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size_t len;
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_enter("");
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if (!rootcell) {
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/* module is loaded with no parameters, or built statically.
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* - in the future we might initialize cell DB here.
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*/
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_leave(" = 0 [no root]");
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return 0;
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}
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cp = strchr(rootcell, ':');
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if (!cp) {
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_debug("kAFS: no VL server IP addresses specified");
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vllist = NULL;
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len = strlen(rootcell);
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} else {
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vllist = cp + 1;
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len = cp - rootcell;
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}
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/* allocate a cell record for the root cell */
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new_root = afs_lookup_cell(net, rootcell, len, vllist, false);
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if (IS_ERR(new_root)) {
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_leave(" = %ld", PTR_ERR(new_root));
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return PTR_ERR(new_root);
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}
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if (!test_and_set_bit(AFS_CELL_FL_NO_GC, &new_root->flags))
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afs_get_cell(new_root);
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/* install the new cell */
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write_seqlock(&net->cells_lock);
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old_root = rcu_access_pointer(net->ws_cell);
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rcu_assign_pointer(net->ws_cell, new_root);
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write_sequnlock(&net->cells_lock);
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afs_put_cell(net, old_root);
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_leave(" = 0");
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return 0;
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}
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/*
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* Update a cell's VL server address list from the DNS.
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*/
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static void afs_update_cell(struct afs_cell *cell)
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{
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struct afs_vlserver_list *vllist, *old;
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unsigned int min_ttl = READ_ONCE(afs_cell_min_ttl);
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unsigned int max_ttl = READ_ONCE(afs_cell_max_ttl);
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time64_t now, expiry = 0;
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_enter("%s", cell->name);
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vllist = afs_dns_query(cell, &expiry);
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now = ktime_get_real_seconds();
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if (min_ttl > max_ttl)
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max_ttl = min_ttl;
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if (expiry < now + min_ttl)
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expiry = now + min_ttl;
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else if (expiry > now + max_ttl)
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expiry = now + max_ttl;
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if (IS_ERR(vllist)) {
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switch (PTR_ERR(vllist)) {
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case -ENODATA:
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case -EDESTADDRREQ:
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/* The DNS said that the cell does not exist or there
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* weren't any addresses to be had.
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*/
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set_bit(AFS_CELL_FL_NOT_FOUND, &cell->flags);
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clear_bit(AFS_CELL_FL_DNS_FAIL, &cell->flags);
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cell->dns_expiry = expiry;
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break;
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case -EAGAIN:
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case -ECONNREFUSED:
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default:
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set_bit(AFS_CELL_FL_DNS_FAIL, &cell->flags);
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cell->dns_expiry = now + 10;
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break;
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}
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cell->error = -EDESTADDRREQ;
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} else {
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clear_bit(AFS_CELL_FL_DNS_FAIL, &cell->flags);
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clear_bit(AFS_CELL_FL_NOT_FOUND, &cell->flags);
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/* Exclusion on changing vl_addrs is achieved by a
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* non-reentrant work item.
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*/
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old = rcu_dereference_protected(cell->vl_servers, true);
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rcu_assign_pointer(cell->vl_servers, vllist);
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cell->dns_expiry = expiry;
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if (old)
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afs_put_vlserverlist(cell->net, old);
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}
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if (test_and_clear_bit(AFS_CELL_FL_NO_LOOKUP_YET, &cell->flags))
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wake_up_bit(&cell->flags, AFS_CELL_FL_NO_LOOKUP_YET);
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now = ktime_get_real_seconds();
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afs_set_cell_timer(cell->net, cell->dns_expiry - now);
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_leave("");
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}
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/*
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* Destroy a cell record
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*/
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static void afs_cell_destroy(struct rcu_head *rcu)
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{
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struct afs_cell *cell = container_of(rcu, struct afs_cell, rcu);
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_enter("%p{%s}", cell, cell->name);
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ASSERTCMP(atomic_read(&cell->usage), ==, 0);
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afs_put_vlserverlist(cell->net, rcu_access_pointer(cell->vl_servers));
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key_put(cell->anonymous_key);
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kfree(cell);
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_leave(" [destroyed]");
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}
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/*
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* Queue the cell manager.
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*/
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static void afs_queue_cell_manager(struct afs_net *net)
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{
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int outstanding = atomic_inc_return(&net->cells_outstanding);
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_enter("%d", outstanding);
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if (!queue_work(afs_wq, &net->cells_manager))
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afs_dec_cells_outstanding(net);
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}
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/*
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* Cell management timer. We have an increment on cells_outstanding that we
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* need to pass along to the work item.
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*/
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void afs_cells_timer(struct timer_list *timer)
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{
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struct afs_net *net = container_of(timer, struct afs_net, cells_timer);
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_enter("");
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if (!queue_work(afs_wq, &net->cells_manager))
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afs_dec_cells_outstanding(net);
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}
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/*
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* Get a reference on a cell record.
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*/
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struct afs_cell *afs_get_cell(struct afs_cell *cell)
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{
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atomic_inc(&cell->usage);
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return cell;
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}
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/*
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* Drop a reference on a cell record.
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*/
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void afs_put_cell(struct afs_net *net, struct afs_cell *cell)
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{
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time64_t now, expire_delay;
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if (!cell)
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return;
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_enter("%s", cell->name);
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now = ktime_get_real_seconds();
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cell->last_inactive = now;
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expire_delay = 0;
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if (!test_bit(AFS_CELL_FL_DNS_FAIL, &cell->flags) &&
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!test_bit(AFS_CELL_FL_NOT_FOUND, &cell->flags))
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expire_delay = afs_cell_gc_delay;
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if (atomic_dec_return(&cell->usage) > 1)
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return;
|
|
|
|
/* 'cell' may now be garbage collected. */
|
|
afs_set_cell_timer(net, expire_delay);
|
|
}
|
|
|
|
/*
|
|
* Allocate a key to use as a placeholder for anonymous user security.
|
|
*/
|
|
static int afs_alloc_anon_key(struct afs_cell *cell)
|
|
{
|
|
struct key *key;
|
|
char keyname[4 + AFS_MAXCELLNAME + 1], *cp, *dp;
|
|
|
|
/* Create a key to represent an anonymous user. */
|
|
memcpy(keyname, "afs@", 4);
|
|
dp = keyname + 4;
|
|
cp = cell->name;
|
|
do {
|
|
*dp++ = tolower(*cp);
|
|
} while (*cp++);
|
|
|
|
key = rxrpc_get_null_key(keyname);
|
|
if (IS_ERR(key))
|
|
return PTR_ERR(key);
|
|
|
|
cell->anonymous_key = key;
|
|
|
|
_debug("anon key %p{%x}",
|
|
cell->anonymous_key, key_serial(cell->anonymous_key));
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Activate a cell.
|
|
*/
|
|
static int afs_activate_cell(struct afs_net *net, struct afs_cell *cell)
|
|
{
|
|
struct hlist_node **p;
|
|
struct afs_cell *pcell;
|
|
int ret;
|
|
|
|
if (!cell->anonymous_key) {
|
|
ret = afs_alloc_anon_key(cell);
|
|
if (ret < 0)
|
|
return ret;
|
|
}
|
|
|
|
#ifdef CONFIG_AFS_FSCACHE
|
|
cell->cache = fscache_acquire_cookie(afs_cache_netfs.primary_index,
|
|
&afs_cell_cache_index_def,
|
|
cell->name, strlen(cell->name),
|
|
NULL, 0,
|
|
cell, 0, true);
|
|
#endif
|
|
ret = afs_proc_cell_setup(cell);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
mutex_lock(&net->proc_cells_lock);
|
|
for (p = &net->proc_cells.first; *p; p = &(*p)->next) {
|
|
pcell = hlist_entry(*p, struct afs_cell, proc_link);
|
|
if (strcmp(cell->name, pcell->name) < 0)
|
|
break;
|
|
}
|
|
|
|
cell->proc_link.pprev = p;
|
|
cell->proc_link.next = *p;
|
|
rcu_assign_pointer(*p, &cell->proc_link.next);
|
|
if (cell->proc_link.next)
|
|
cell->proc_link.next->pprev = &cell->proc_link.next;
|
|
|
|
afs_dynroot_mkdir(net, cell);
|
|
mutex_unlock(&net->proc_cells_lock);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Deactivate a cell.
|
|
*/
|
|
static void afs_deactivate_cell(struct afs_net *net, struct afs_cell *cell)
|
|
{
|
|
_enter("%s", cell->name);
|
|
|
|
afs_proc_cell_remove(cell);
|
|
|
|
mutex_lock(&net->proc_cells_lock);
|
|
hlist_del_rcu(&cell->proc_link);
|
|
afs_dynroot_rmdir(net, cell);
|
|
mutex_unlock(&net->proc_cells_lock);
|
|
|
|
#ifdef CONFIG_AFS_FSCACHE
|
|
fscache_relinquish_cookie(cell->cache, NULL, false);
|
|
cell->cache = NULL;
|
|
#endif
|
|
|
|
_leave("");
|
|
}
|
|
|
|
/*
|
|
* Manage a cell record, initialising and destroying it, maintaining its DNS
|
|
* records.
|
|
*/
|
|
static void afs_manage_cell(struct work_struct *work)
|
|
{
|
|
struct afs_cell *cell = container_of(work, struct afs_cell, manager);
|
|
struct afs_net *net = cell->net;
|
|
bool deleted;
|
|
int ret, usage;
|
|
|
|
_enter("%s", cell->name);
|
|
|
|
again:
|
|
_debug("state %u", cell->state);
|
|
switch (cell->state) {
|
|
case AFS_CELL_INACTIVE:
|
|
case AFS_CELL_FAILED:
|
|
write_seqlock(&net->cells_lock);
|
|
usage = 1;
|
|
deleted = atomic_try_cmpxchg_relaxed(&cell->usage, &usage, 0);
|
|
if (deleted)
|
|
rb_erase(&cell->net_node, &net->cells);
|
|
write_sequnlock(&net->cells_lock);
|
|
if (deleted)
|
|
goto final_destruction;
|
|
if (cell->state == AFS_CELL_FAILED)
|
|
goto done;
|
|
cell->state = AFS_CELL_UNSET;
|
|
goto again;
|
|
|
|
case AFS_CELL_UNSET:
|
|
cell->state = AFS_CELL_ACTIVATING;
|
|
goto again;
|
|
|
|
case AFS_CELL_ACTIVATING:
|
|
ret = afs_activate_cell(net, cell);
|
|
if (ret < 0)
|
|
goto activation_failed;
|
|
|
|
cell->state = AFS_CELL_ACTIVE;
|
|
smp_wmb();
|
|
clear_bit(AFS_CELL_FL_NOT_READY, &cell->flags);
|
|
wake_up_bit(&cell->flags, AFS_CELL_FL_NOT_READY);
|
|
goto again;
|
|
|
|
case AFS_CELL_ACTIVE:
|
|
if (atomic_read(&cell->usage) > 1) {
|
|
time64_t now = ktime_get_real_seconds();
|
|
if (cell->dns_expiry <= now && net->live)
|
|
afs_update_cell(cell);
|
|
goto done;
|
|
}
|
|
cell->state = AFS_CELL_DEACTIVATING;
|
|
goto again;
|
|
|
|
case AFS_CELL_DEACTIVATING:
|
|
set_bit(AFS_CELL_FL_NOT_READY, &cell->flags);
|
|
if (atomic_read(&cell->usage) > 1)
|
|
goto reverse_deactivation;
|
|
afs_deactivate_cell(net, cell);
|
|
cell->state = AFS_CELL_INACTIVE;
|
|
goto again;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
_debug("bad state %u", cell->state);
|
|
BUG(); /* Unhandled state */
|
|
|
|
activation_failed:
|
|
cell->error = ret;
|
|
afs_deactivate_cell(net, cell);
|
|
|
|
cell->state = AFS_CELL_FAILED;
|
|
smp_wmb();
|
|
if (test_and_clear_bit(AFS_CELL_FL_NOT_READY, &cell->flags))
|
|
wake_up_bit(&cell->flags, AFS_CELL_FL_NOT_READY);
|
|
goto again;
|
|
|
|
reverse_deactivation:
|
|
cell->state = AFS_CELL_ACTIVE;
|
|
smp_wmb();
|
|
clear_bit(AFS_CELL_FL_NOT_READY, &cell->flags);
|
|
wake_up_bit(&cell->flags, AFS_CELL_FL_NOT_READY);
|
|
_leave(" [deact->act]");
|
|
return;
|
|
|
|
done:
|
|
_leave(" [done %u]", cell->state);
|
|
return;
|
|
|
|
final_destruction:
|
|
call_rcu(&cell->rcu, afs_cell_destroy);
|
|
afs_dec_cells_outstanding(net);
|
|
_leave(" [destruct %d]", atomic_read(&net->cells_outstanding));
|
|
}
|
|
|
|
/*
|
|
* Manage the records of cells known to a network namespace. This includes
|
|
* updating the DNS records and garbage collecting unused cells that were
|
|
* automatically added.
|
|
*
|
|
* Note that constructed cell records may only be removed from net->cells by
|
|
* this work item, so it is safe for this work item to stash a cursor pointing
|
|
* into the tree and then return to caller (provided it skips cells that are
|
|
* still under construction).
|
|
*
|
|
* Note also that we were given an increment on net->cells_outstanding by
|
|
* whoever queued us that we need to deal with before returning.
|
|
*/
|
|
void afs_manage_cells(struct work_struct *work)
|
|
{
|
|
struct afs_net *net = container_of(work, struct afs_net, cells_manager);
|
|
struct rb_node *cursor;
|
|
time64_t now = ktime_get_real_seconds(), next_manage = TIME64_MAX;
|
|
bool purging = !net->live;
|
|
|
|
_enter("");
|
|
|
|
/* Trawl the cell database looking for cells that have expired from
|
|
* lack of use and cells whose DNS results have expired and dispatch
|
|
* their managers.
|
|
*/
|
|
read_seqlock_excl(&net->cells_lock);
|
|
|
|
for (cursor = rb_first(&net->cells); cursor; cursor = rb_next(cursor)) {
|
|
struct afs_cell *cell =
|
|
rb_entry(cursor, struct afs_cell, net_node);
|
|
unsigned usage;
|
|
bool sched_cell = false;
|
|
|
|
usage = atomic_read(&cell->usage);
|
|
_debug("manage %s %u", cell->name, usage);
|
|
|
|
ASSERTCMP(usage, >=, 1);
|
|
|
|
if (purging) {
|
|
if (test_and_clear_bit(AFS_CELL_FL_NO_GC, &cell->flags))
|
|
usage = atomic_dec_return(&cell->usage);
|
|
ASSERTCMP(usage, ==, 1);
|
|
}
|
|
|
|
if (usage == 1) {
|
|
time64_t expire_at = cell->last_inactive;
|
|
|
|
if (!test_bit(AFS_CELL_FL_DNS_FAIL, &cell->flags) &&
|
|
!test_bit(AFS_CELL_FL_NOT_FOUND, &cell->flags))
|
|
expire_at += afs_cell_gc_delay;
|
|
if (purging || expire_at <= now)
|
|
sched_cell = true;
|
|
else if (expire_at < next_manage)
|
|
next_manage = expire_at;
|
|
}
|
|
|
|
if (!purging) {
|
|
if (cell->dns_expiry <= now)
|
|
sched_cell = true;
|
|
else if (cell->dns_expiry <= next_manage)
|
|
next_manage = cell->dns_expiry;
|
|
}
|
|
|
|
if (sched_cell)
|
|
queue_work(afs_wq, &cell->manager);
|
|
}
|
|
|
|
read_sequnlock_excl(&net->cells_lock);
|
|
|
|
/* Update the timer on the way out. We have to pass an increment on
|
|
* cells_outstanding in the namespace that we are in to the timer or
|
|
* the work scheduler.
|
|
*/
|
|
if (!purging && next_manage < TIME64_MAX) {
|
|
now = ktime_get_real_seconds();
|
|
|
|
if (next_manage - now <= 0) {
|
|
if (queue_work(afs_wq, &net->cells_manager))
|
|
atomic_inc(&net->cells_outstanding);
|
|
} else {
|
|
afs_set_cell_timer(net, next_manage - now);
|
|
}
|
|
}
|
|
|
|
afs_dec_cells_outstanding(net);
|
|
_leave(" [%d]", atomic_read(&net->cells_outstanding));
|
|
}
|
|
|
|
/*
|
|
* Purge in-memory cell database.
|
|
*/
|
|
void afs_cell_purge(struct afs_net *net)
|
|
{
|
|
struct afs_cell *ws;
|
|
|
|
_enter("");
|
|
|
|
write_seqlock(&net->cells_lock);
|
|
ws = rcu_access_pointer(net->ws_cell);
|
|
RCU_INIT_POINTER(net->ws_cell, NULL);
|
|
write_sequnlock(&net->cells_lock);
|
|
afs_put_cell(net, ws);
|
|
|
|
_debug("del timer");
|
|
if (del_timer_sync(&net->cells_timer))
|
|
atomic_dec(&net->cells_outstanding);
|
|
|
|
_debug("kick mgr");
|
|
afs_queue_cell_manager(net);
|
|
|
|
_debug("wait");
|
|
wait_var_event(&net->cells_outstanding,
|
|
!atomic_read(&net->cells_outstanding));
|
|
_leave("");
|
|
}
|