1
linux/fs/nfs/nfs4state.c
Yanjun Zhang a848c29e34 NFSv4: Prevent NULL-pointer dereference in nfs42_complete_copies()
On the node of an NFS client, some files saved in the mountpoint of the
NFS server were copied to another location of the same NFS server.
Accidentally, the nfs42_complete_copies() got a NULL-pointer dereference
crash with the following syslog:

[232064.838881] NFSv4: state recovery failed for open file nfs/pvc-12b5200d-cd0f-46a3-b9f0-af8f4fe0ef64.qcow2, error = -116
[232064.839360] NFSv4: state recovery failed for open file nfs/pvc-12b5200d-cd0f-46a3-b9f0-af8f4fe0ef64.qcow2, error = -116
[232066.588183] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000058
[232066.588586] Mem abort info:
[232066.588701]   ESR = 0x0000000096000007
[232066.588862]   EC = 0x25: DABT (current EL), IL = 32 bits
[232066.589084]   SET = 0, FnV = 0
[232066.589216]   EA = 0, S1PTW = 0
[232066.589340]   FSC = 0x07: level 3 translation fault
[232066.589559] Data abort info:
[232066.589683]   ISV = 0, ISS = 0x00000007
[232066.589842]   CM = 0, WnR = 0
[232066.589967] user pgtable: 64k pages, 48-bit VAs, pgdp=00002000956ff400
[232066.590231] [0000000000000058] pgd=08001100ae100003, p4d=08001100ae100003, pud=08001100ae100003, pmd=08001100b3c00003, pte=0000000000000000
[232066.590757] Internal error: Oops: 96000007 [#1] SMP
[232066.590958] Modules linked in: rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace fscache netfs ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm vhost_net vhost vhost_iotlb tap tun ipt_rpfilter xt_multiport ip_set_hash_ip ip_set_hash_net xfrm_interface xfrm6_tunnel tunnel4 tunnel6 esp4 ah4 wireguard libcurve25519_generic veth xt_addrtype xt_set nf_conntrack_netlink ip_set_hash_ipportnet ip_set_hash_ipportip ip_set_bitmap_port ip_set_hash_ipport dummy ip_set ip_vs_sh ip_vs_wrr ip_vs_rr ip_vs iptable_filter sch_ingress nfnetlink_cttimeout vport_gre ip_gre ip_tunnel gre vport_geneve geneve vport_vxlan vxlan ip6_udp_tunnel udp_tunnel openvswitch nf_conncount dm_round_robin dm_service_time dm_multipath xt_nat xt_MASQUERADE nft_chain_nat nf_nat xt_mark xt_conntrack xt_comment nft_compat nft_counter nf_tables nfnetlink ocfs2 ocfs2_nodemanager ocfs2_stackglue iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ipmi_ssif nbd overlay 8021q garp mrp bonding tls rfkill sunrpc ext4 mbcache jbd2
[232066.591052]  vfat fat cas_cache cas_disk ses enclosure scsi_transport_sas sg acpi_ipmi ipmi_si ipmi_devintf ipmi_msghandler ip_tables vfio_pci vfio_pci_core vfio_virqfd vfio_iommu_type1 vfio dm_mirror dm_region_hash dm_log dm_mod nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 br_netfilter bridge stp llc fuse xfs libcrc32c ast drm_vram_helper qla2xxx drm_kms_helper syscopyarea crct10dif_ce sysfillrect ghash_ce sysimgblt sha2_ce fb_sys_fops cec sha256_arm64 sha1_ce drm_ttm_helper ttm nvme_fc igb sbsa_gwdt nvme_fabrics drm nvme_core i2c_algo_bit i40e scsi_transport_fc megaraid_sas aes_neon_bs
[232066.596953] CPU: 6 PID: 4124696 Comm: 10.253.166.125- Kdump: loaded Not tainted 5.15.131-9.cl9_ocfs2.aarch64 #1
[232066.597356] Hardware name: Great Wall .\x93\x8e...RF6260 V5/GWMSSE2GL1T, BIOS T656FBE_V3.0.18 2024-01-06
[232066.597721] pstate: 20400009 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[232066.598034] pc : nfs4_reclaim_open_state+0x220/0x800 [nfsv4]
[232066.598327] lr : nfs4_reclaim_open_state+0x12c/0x800 [nfsv4]
[232066.598595] sp : ffff8000f568fc70
[232066.598731] x29: ffff8000f568fc70 x28: 0000000000001000 x27: ffff21003db33000
[232066.599030] x26: ffff800005521ae0 x25: ffff0100f98fa3f0 x24: 0000000000000001
[232066.599319] x23: ffff800009920008 x22: ffff21003db33040 x21: ffff21003db33050
[232066.599628] x20: ffff410172fe9e40 x19: ffff410172fe9e00 x18: 0000000000000000
[232066.599914] x17: 0000000000000000 x16: 0000000000000004 x15: 0000000000000000
[232066.600195] x14: 0000000000000000 x13: ffff800008e685a8 x12: 00000000eac0c6e6
[232066.600498] x11: 0000000000000000 x10: 0000000000000008 x9 : ffff8000054e5828
[232066.600784] x8 : 00000000ffffffbf x7 : 0000000000000001 x6 : 000000000a9eb14a
[232066.601062] x5 : 0000000000000000 x4 : ffff70ff8a14a800 x3 : 0000000000000058
[232066.601348] x2 : 0000000000000001 x1 : 54dce46366daa6c6 x0 : 0000000000000000
[232066.601636] Call trace:
[232066.601749]  nfs4_reclaim_open_state+0x220/0x800 [nfsv4]
[232066.601998]  nfs4_do_reclaim+0x1b8/0x28c [nfsv4]
[232066.602218]  nfs4_state_manager+0x928/0x10f0 [nfsv4]
[232066.602455]  nfs4_run_state_manager+0x78/0x1b0 [nfsv4]
[232066.602690]  kthread+0x110/0x114
[232066.602830]  ret_from_fork+0x10/0x20
[232066.602985] Code: 1400000d f9403f20 f9402e61 91016003 (f9402c00)
[232066.603284] SMP: stopping secondary CPUs
[232066.606936] Starting crashdump kernel...
[232066.607146] Bye!

Analysing the vmcore, we know that nfs4_copy_state listed by destination
nfs_server->ss_copies was added by the field copies in handle_async_copy(),
and we found a waiting copy process with the stack as:
PID: 3511963  TASK: ffff710028b47e00  CPU: 0   COMMAND: "cp"
 #0 [ffff8001116ef740] __switch_to at ffff8000081b92f4
 #1 [ffff8001116ef760] __schedule at ffff800008dd0650
 #2 [ffff8001116ef7c0] schedule at ffff800008dd0a00
 #3 [ffff8001116ef7e0] schedule_timeout at ffff800008dd6aa0
 #4 [ffff8001116ef860] __wait_for_common at ffff800008dd166c
 #5 [ffff8001116ef8e0] wait_for_completion_interruptible at ffff800008dd1898
 #6 [ffff8001116ef8f0] handle_async_copy at ffff8000055142f4 [nfsv4]
 #7 [ffff8001116ef970] _nfs42_proc_copy at ffff8000055147c8 [nfsv4]
 #8 [ffff8001116efa80] nfs42_proc_copy at ffff800005514cf0 [nfsv4]
 #9 [ffff8001116efc50] __nfs4_copy_file_range.constprop.0 at ffff8000054ed694 [nfsv4]

The NULL-pointer dereference was due to nfs42_complete_copies() listed
the nfs_server->ss_copies by the field ss_copies of nfs4_copy_state.
So the nfs4_copy_state address ffff0100f98fa3f0 was offset by 0x10 and
the data accessed through this pointer was also incorrect. Generally,
the ordered list nfs4_state_owner->so_states indicate open(O_RDWR) or
open(O_WRITE) states are reclaimed firstly by nfs4_reclaim_open_state().
When destination state reclaim is failed with NFS_STATE_RECOVERY_FAILED
and copies are not deleted in nfs_server->ss_copies, the source state
may be passed to the nfs42_complete_copies() process earlier, resulting
in this crash scene finally. To solve this issue, we add a list_head
nfs_server->ss_src_copies for a server-to-server copy specially.

Fixes: 0e65a32c8a ("NFS: handle source server reboot")
Signed-off-by: Yanjun Zhang <zhangyanjun@cestc.cn>
Reviewed-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
2024-10-03 16:19:13 -04:00

2785 lines
73 KiB
C

/*
* fs/nfs/nfs4state.c
*
* Client-side XDR for NFSv4.
*
* Copyright (c) 2002 The Regents of the University of Michigan.
* All rights reserved.
*
* Kendrick Smith <kmsmith@umich.edu>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Implementation of the NFSv4 state model. For the time being,
* this is minimal, but will be made much more complex in a
* subsequent patch.
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/nfs_fs.h>
#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/random.h>
#include <linux/ratelimit.h>
#include <linux/workqueue.h>
#include <linux/bitops.h>
#include <linux/jiffies.h>
#include <linux/sched/mm.h>
#include <linux/sunrpc/clnt.h>
#include "nfs4_fs.h"
#include "callback.h"
#include "delegation.h"
#include "internal.h"
#include "nfs4idmap.h"
#include "nfs4session.h"
#include "pnfs.h"
#include "netns.h"
#include "nfs4trace.h"
#define NFSDBG_FACILITY NFSDBG_STATE
#define OPENOWNER_POOL_SIZE 8
static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp);
const nfs4_stateid zero_stateid = {
{ .data = { 0 } },
.type = NFS4_SPECIAL_STATEID_TYPE,
};
const nfs4_stateid invalid_stateid = {
{
/* Funky initialiser keeps older gcc versions happy */
.data = { 0xff, 0xff, 0xff, 0xff, 0 },
},
.type = NFS4_INVALID_STATEID_TYPE,
};
const nfs4_stateid current_stateid = {
{
/* Funky initialiser keeps older gcc versions happy */
.data = { 0x0, 0x0, 0x0, 0x1, 0 },
},
.type = NFS4_SPECIAL_STATEID_TYPE,
};
static DEFINE_MUTEX(nfs_clid_init_mutex);
static int nfs4_setup_state_renewal(struct nfs_client *clp)
{
int status;
struct nfs_fsinfo fsinfo;
if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
nfs4_schedule_state_renewal(clp);
return 0;
}
status = nfs4_proc_get_lease_time(clp, &fsinfo);
if (status == 0) {
nfs4_set_lease_period(clp, fsinfo.lease_time * HZ);
nfs4_schedule_state_renewal(clp);
}
return status;
}
int nfs4_init_clientid(struct nfs_client *clp, const struct cred *cred)
{
struct nfs4_setclientid_res clid = {
.clientid = clp->cl_clientid,
.confirm = clp->cl_confirm,
};
unsigned short port;
int status;
struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
goto do_confirm;
port = nn->nfs_callback_tcpport;
if (clp->cl_addr.ss_family == AF_INET6)
port = nn->nfs_callback_tcpport6;
status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
if (status != 0)
goto out;
clp->cl_clientid = clid.clientid;
clp->cl_confirm = clid.confirm;
set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
do_confirm:
status = nfs4_proc_setclientid_confirm(clp, &clid, cred);
if (status != 0)
goto out;
clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
nfs4_setup_state_renewal(clp);
out:
return status;
}
/**
* nfs40_discover_server_trunking - Detect server IP address trunking (mv0)
*
* @clp: nfs_client under test
* @result: OUT: found nfs_client, or clp
* @cred: credential to use for trunking test
*
* Returns zero, a negative errno, or a negative NFS4ERR status.
* If zero is returned, an nfs_client pointer is planted in
* "result".
*
* Note: The returned client may not yet be marked ready.
*/
int nfs40_discover_server_trunking(struct nfs_client *clp,
struct nfs_client **result,
const struct cred *cred)
{
struct nfs4_setclientid_res clid = {
.clientid = clp->cl_clientid,
.confirm = clp->cl_confirm,
};
struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
unsigned short port;
int status;
port = nn->nfs_callback_tcpport;
if (clp->cl_addr.ss_family == AF_INET6)
port = nn->nfs_callback_tcpport6;
status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
if (status != 0)
goto out;
clp->cl_clientid = clid.clientid;
clp->cl_confirm = clid.confirm;
status = nfs40_walk_client_list(clp, result, cred);
if (status == 0) {
/* Sustain the lease, even if it's empty. If the clientid4
* goes stale it's of no use for trunking discovery. */
nfs4_schedule_state_renewal(*result);
/* If the client state need to recover, do it. */
if (clp->cl_state)
nfs4_schedule_state_manager(clp);
}
out:
return status;
}
const struct cred *nfs4_get_machine_cred(struct nfs_client *clp)
{
return get_cred(rpc_machine_cred());
}
static void nfs4_root_machine_cred(struct nfs_client *clp)
{
/* Force root creds instead of machine */
clp->cl_principal = NULL;
clp->cl_rpcclient->cl_principal = NULL;
}
static const struct cred *
nfs4_get_renew_cred_server_locked(struct nfs_server *server)
{
const struct cred *cred = NULL;
struct nfs4_state_owner *sp;
struct rb_node *pos;
for (pos = rb_first(&server->state_owners);
pos != NULL;
pos = rb_next(pos)) {
sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
if (list_empty(&sp->so_states))
continue;
cred = get_cred(sp->so_cred);
break;
}
return cred;
}
/**
* nfs4_get_renew_cred - Acquire credential for a renew operation
* @clp: client state handle
*
* Returns an rpc_cred with reference count bumped, or NULL.
* Caller must hold clp->cl_lock.
*/
const struct cred *nfs4_get_renew_cred(struct nfs_client *clp)
{
const struct cred *cred = NULL;
struct nfs_server *server;
/* Use machine credentials if available */
cred = nfs4_get_machine_cred(clp);
if (cred != NULL)
goto out;
spin_lock(&clp->cl_lock);
rcu_read_lock();
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
cred = nfs4_get_renew_cred_server_locked(server);
if (cred != NULL)
break;
}
rcu_read_unlock();
spin_unlock(&clp->cl_lock);
out:
return cred;
}
static void nfs4_end_drain_slot_table(struct nfs4_slot_table *tbl)
{
if (test_and_clear_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
spin_lock(&tbl->slot_tbl_lock);
nfs41_wake_slot_table(tbl);
spin_unlock(&tbl->slot_tbl_lock);
}
}
static void nfs4_end_drain_session(struct nfs_client *clp)
{
struct nfs4_session *ses = clp->cl_session;
if (clp->cl_slot_tbl) {
nfs4_end_drain_slot_table(clp->cl_slot_tbl);
return;
}
if (ses != NULL) {
nfs4_end_drain_slot_table(&ses->bc_slot_table);
nfs4_end_drain_slot_table(&ses->fc_slot_table);
}
}
static int nfs4_drain_slot_tbl(struct nfs4_slot_table *tbl)
{
set_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state);
spin_lock(&tbl->slot_tbl_lock);
if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
reinit_completion(&tbl->complete);
spin_unlock(&tbl->slot_tbl_lock);
return wait_for_completion_interruptible(&tbl->complete);
}
spin_unlock(&tbl->slot_tbl_lock);
return 0;
}
static int nfs4_begin_drain_session(struct nfs_client *clp)
{
struct nfs4_session *ses = clp->cl_session;
int ret;
if (clp->cl_slot_tbl)
return nfs4_drain_slot_tbl(clp->cl_slot_tbl);
/* back channel */
ret = nfs4_drain_slot_tbl(&ses->bc_slot_table);
if (ret)
return ret;
/* fore channel */
return nfs4_drain_slot_tbl(&ses->fc_slot_table);
}
#if defined(CONFIG_NFS_V4_1)
static void nfs41_finish_session_reset(struct nfs_client *clp)
{
clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
/* create_session negotiated new slot table */
clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
nfs4_setup_state_renewal(clp);
}
int nfs41_init_clientid(struct nfs_client *clp, const struct cred *cred)
{
int status;
if (test_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state))
goto do_confirm;
status = nfs4_proc_exchange_id(clp, cred);
if (status != 0)
goto out;
set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
do_confirm:
status = nfs4_proc_create_session(clp, cred);
if (status != 0)
goto out;
if (!(clp->cl_exchange_flags & EXCHGID4_FLAG_CONFIRMED_R))
nfs4_state_start_reclaim_reboot(clp);
nfs41_finish_session_reset(clp);
nfs_mark_client_ready(clp, NFS_CS_READY);
out:
return status;
}
/**
* nfs41_discover_server_trunking - Detect server IP address trunking (mv1)
*
* @clp: nfs_client under test
* @result: OUT: found nfs_client, or clp
* @cred: credential to use for trunking test
*
* Returns NFS4_OK, a negative errno, or a negative NFS4ERR status.
* If NFS4_OK is returned, an nfs_client pointer is planted in
* "result".
*
* Note: The returned client may not yet be marked ready.
*/
int nfs41_discover_server_trunking(struct nfs_client *clp,
struct nfs_client **result,
const struct cred *cred)
{
int status;
status = nfs4_proc_exchange_id(clp, cred);
if (status != NFS4_OK)
return status;
status = nfs41_walk_client_list(clp, result, cred);
if (status < 0)
return status;
if (clp != *result)
return 0;
/*
* Purge state if the client id was established in a prior
* instance and the client id could not have arrived on the
* server via Transparent State Migration.
*/
if (clp->cl_exchange_flags & EXCHGID4_FLAG_CONFIRMED_R) {
if (!test_bit(NFS_CS_TSM_POSSIBLE, &clp->cl_flags))
set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
else
set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
}
nfs4_schedule_state_manager(clp);
status = nfs_wait_client_init_complete(clp);
if (status < 0)
nfs_put_client(clp);
return status;
}
#endif /* CONFIG_NFS_V4_1 */
/**
* nfs4_get_clid_cred - Acquire credential for a setclientid operation
* @clp: client state handle
*
* Returns a cred with reference count bumped, or NULL.
*/
const struct cred *nfs4_get_clid_cred(struct nfs_client *clp)
{
const struct cred *cred;
cred = nfs4_get_machine_cred(clp);
return cred;
}
static struct nfs4_state_owner *
nfs4_find_state_owner_locked(struct nfs_server *server, const struct cred *cred)
{
struct rb_node **p = &server->state_owners.rb_node,
*parent = NULL;
struct nfs4_state_owner *sp;
int cmp;
while (*p != NULL) {
parent = *p;
sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
cmp = cred_fscmp(cred, sp->so_cred);
if (cmp < 0)
p = &parent->rb_left;
else if (cmp > 0)
p = &parent->rb_right;
else {
if (!list_empty(&sp->so_lru))
list_del_init(&sp->so_lru);
atomic_inc(&sp->so_count);
return sp;
}
}
return NULL;
}
static struct nfs4_state_owner *
nfs4_insert_state_owner_locked(struct nfs4_state_owner *new)
{
struct nfs_server *server = new->so_server;
struct rb_node **p = &server->state_owners.rb_node,
*parent = NULL;
struct nfs4_state_owner *sp;
int cmp;
while (*p != NULL) {
parent = *p;
sp = rb_entry(parent, struct nfs4_state_owner, so_server_node);
cmp = cred_fscmp(new->so_cred, sp->so_cred);
if (cmp < 0)
p = &parent->rb_left;
else if (cmp > 0)
p = &parent->rb_right;
else {
if (!list_empty(&sp->so_lru))
list_del_init(&sp->so_lru);
atomic_inc(&sp->so_count);
return sp;
}
}
rb_link_node(&new->so_server_node, parent, p);
rb_insert_color(&new->so_server_node, &server->state_owners);
return new;
}
static void
nfs4_remove_state_owner_locked(struct nfs4_state_owner *sp)
{
struct nfs_server *server = sp->so_server;
if (!RB_EMPTY_NODE(&sp->so_server_node))
rb_erase(&sp->so_server_node, &server->state_owners);
}
static void
nfs4_init_seqid_counter(struct nfs_seqid_counter *sc)
{
sc->create_time = ktime_get();
sc->flags = 0;
sc->counter = 0;
spin_lock_init(&sc->lock);
INIT_LIST_HEAD(&sc->list);
rpc_init_wait_queue(&sc->wait, "Seqid_waitqueue");
}
static void
nfs4_destroy_seqid_counter(struct nfs_seqid_counter *sc)
{
rpc_destroy_wait_queue(&sc->wait);
}
/*
* nfs4_alloc_state_owner(): this is called on the OPEN or CREATE path to
* create a new state_owner.
*
*/
static struct nfs4_state_owner *
nfs4_alloc_state_owner(struct nfs_server *server,
const struct cred *cred,
gfp_t gfp_flags)
{
struct nfs4_state_owner *sp;
sp = kzalloc(sizeof(*sp), gfp_flags);
if (!sp)
return NULL;
sp->so_seqid.owner_id = atomic64_inc_return(&server->owner_ctr);
sp->so_server = server;
sp->so_cred = get_cred(cred);
spin_lock_init(&sp->so_lock);
INIT_LIST_HEAD(&sp->so_states);
nfs4_init_seqid_counter(&sp->so_seqid);
atomic_set(&sp->so_count, 1);
INIT_LIST_HEAD(&sp->so_lru);
mutex_init(&sp->so_delegreturn_mutex);
return sp;
}
static void
nfs4_reset_state_owner(struct nfs4_state_owner *sp)
{
/* This state_owner is no longer usable, but must
* remain in place so that state recovery can find it
* and the opens associated with it.
* It may also be used for new 'open' request to
* return a delegation to the server.
* So update the 'create_time' so that it looks like
* a new state_owner. This will cause the server to
* request an OPEN_CONFIRM to start a new sequence.
*/
sp->so_seqid.create_time = ktime_get();
}
static void nfs4_free_state_owner(struct nfs4_state_owner *sp)
{
nfs4_destroy_seqid_counter(&sp->so_seqid);
put_cred(sp->so_cred);
kfree(sp);
}
static void nfs4_gc_state_owners(struct nfs_server *server)
{
struct nfs_client *clp = server->nfs_client;
struct nfs4_state_owner *sp, *tmp;
unsigned long time_min, time_max;
LIST_HEAD(doomed);
spin_lock(&clp->cl_lock);
time_max = jiffies;
time_min = (long)time_max - (long)clp->cl_lease_time;
list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
/* NB: LRU is sorted so that oldest is at the head */
if (time_in_range(sp->so_expires, time_min, time_max))
break;
list_move(&sp->so_lru, &doomed);
nfs4_remove_state_owner_locked(sp);
}
spin_unlock(&clp->cl_lock);
list_for_each_entry_safe(sp, tmp, &doomed, so_lru) {
list_del(&sp->so_lru);
nfs4_free_state_owner(sp);
}
}
/**
* nfs4_get_state_owner - Look up a state owner given a credential
* @server: nfs_server to search
* @cred: RPC credential to match
* @gfp_flags: allocation mode
*
* Returns a pointer to an instantiated nfs4_state_owner struct, or NULL.
*/
struct nfs4_state_owner *nfs4_get_state_owner(struct nfs_server *server,
const struct cred *cred,
gfp_t gfp_flags)
{
struct nfs_client *clp = server->nfs_client;
struct nfs4_state_owner *sp, *new;
spin_lock(&clp->cl_lock);
sp = nfs4_find_state_owner_locked(server, cred);
spin_unlock(&clp->cl_lock);
if (sp != NULL)
goto out;
new = nfs4_alloc_state_owner(server, cred, gfp_flags);
if (new == NULL)
goto out;
spin_lock(&clp->cl_lock);
sp = nfs4_insert_state_owner_locked(new);
spin_unlock(&clp->cl_lock);
if (sp != new)
nfs4_free_state_owner(new);
out:
nfs4_gc_state_owners(server);
return sp;
}
/**
* nfs4_put_state_owner - Release a nfs4_state_owner
* @sp: state owner data to release
*
* Note that we keep released state owners on an LRU
* list.
* This caches valid state owners so that they can be
* reused, to avoid the OPEN_CONFIRM on minor version 0.
* It also pins the uniquifier of dropped state owners for
* a while, to ensure that those state owner names are
* never reused.
*/
void nfs4_put_state_owner(struct nfs4_state_owner *sp)
{
struct nfs_server *server = sp->so_server;
struct nfs_client *clp = server->nfs_client;
if (!atomic_dec_and_lock(&sp->so_count, &clp->cl_lock))
return;
sp->so_expires = jiffies;
list_add_tail(&sp->so_lru, &server->state_owners_lru);
spin_unlock(&clp->cl_lock);
}
/**
* nfs4_purge_state_owners - Release all cached state owners
* @server: nfs_server with cached state owners to release
* @head: resulting list of state owners
*
* Called at umount time. Remaining state owners will be on
* the LRU with ref count of zero.
* Note that the state owners are not freed, but are added
* to the list @head, which can later be used as an argument
* to nfs4_free_state_owners.
*/
void nfs4_purge_state_owners(struct nfs_server *server, struct list_head *head)
{
struct nfs_client *clp = server->nfs_client;
struct nfs4_state_owner *sp, *tmp;
spin_lock(&clp->cl_lock);
list_for_each_entry_safe(sp, tmp, &server->state_owners_lru, so_lru) {
list_move(&sp->so_lru, head);
nfs4_remove_state_owner_locked(sp);
}
spin_unlock(&clp->cl_lock);
}
/**
* nfs4_free_state_owners - Release all cached state owners
* @head: resulting list of state owners
*
* Frees a list of state owners that was generated by
* nfs4_purge_state_owners
*/
void nfs4_free_state_owners(struct list_head *head)
{
struct nfs4_state_owner *sp, *tmp;
list_for_each_entry_safe(sp, tmp, head, so_lru) {
list_del(&sp->so_lru);
nfs4_free_state_owner(sp);
}
}
static struct nfs4_state *
nfs4_alloc_open_state(void)
{
struct nfs4_state *state;
state = kzalloc(sizeof(*state), GFP_KERNEL_ACCOUNT);
if (!state)
return NULL;
refcount_set(&state->count, 1);
INIT_LIST_HEAD(&state->lock_states);
spin_lock_init(&state->state_lock);
seqlock_init(&state->seqlock);
init_waitqueue_head(&state->waitq);
return state;
}
void
nfs4_state_set_mode_locked(struct nfs4_state *state, fmode_t fmode)
{
if (state->state == fmode)
return;
/* NB! List reordering - see the reclaim code for why. */
if ((fmode & FMODE_WRITE) != (state->state & FMODE_WRITE)) {
if (fmode & FMODE_WRITE)
list_move(&state->open_states, &state->owner->so_states);
else
list_move_tail(&state->open_states, &state->owner->so_states);
}
state->state = fmode;
}
static struct nfs4_state *
__nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
{
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs4_state *state;
list_for_each_entry_rcu(state, &nfsi->open_states, inode_states) {
if (state->owner != owner)
continue;
if (!nfs4_valid_open_stateid(state))
continue;
if (refcount_inc_not_zero(&state->count))
return state;
}
return NULL;
}
static void
nfs4_free_open_state(struct nfs4_state *state)
{
kfree_rcu(state, rcu_head);
}
struct nfs4_state *
nfs4_get_open_state(struct inode *inode, struct nfs4_state_owner *owner)
{
struct nfs4_state *state, *new;
struct nfs_inode *nfsi = NFS_I(inode);
rcu_read_lock();
state = __nfs4_find_state_byowner(inode, owner);
rcu_read_unlock();
if (state)
goto out;
new = nfs4_alloc_open_state();
spin_lock(&owner->so_lock);
spin_lock(&inode->i_lock);
state = __nfs4_find_state_byowner(inode, owner);
if (state == NULL && new != NULL) {
state = new;
state->owner = owner;
atomic_inc(&owner->so_count);
ihold(inode);
state->inode = inode;
list_add_rcu(&state->inode_states, &nfsi->open_states);
spin_unlock(&inode->i_lock);
/* Note: The reclaim code dictates that we add stateless
* and read-only stateids to the end of the list */
list_add_tail(&state->open_states, &owner->so_states);
spin_unlock(&owner->so_lock);
} else {
spin_unlock(&inode->i_lock);
spin_unlock(&owner->so_lock);
if (new)
nfs4_free_open_state(new);
}
out:
return state;
}
void nfs4_put_open_state(struct nfs4_state *state)
{
struct inode *inode = state->inode;
struct nfs4_state_owner *owner = state->owner;
if (!refcount_dec_and_lock(&state->count, &owner->so_lock))
return;
spin_lock(&inode->i_lock);
list_del_rcu(&state->inode_states);
list_del(&state->open_states);
spin_unlock(&inode->i_lock);
spin_unlock(&owner->so_lock);
nfs4_inode_return_delegation_on_close(inode);
iput(inode);
nfs4_free_open_state(state);
nfs4_put_state_owner(owner);
}
/*
* Close the current file.
*/
static void __nfs4_close(struct nfs4_state *state,
fmode_t fmode, gfp_t gfp_mask, int wait)
{
struct nfs4_state_owner *owner = state->owner;
int call_close = 0;
fmode_t newstate;
atomic_inc(&owner->so_count);
/* Protect against nfs4_find_state() */
spin_lock(&owner->so_lock);
switch (fmode & (FMODE_READ | FMODE_WRITE)) {
case FMODE_READ:
state->n_rdonly--;
break;
case FMODE_WRITE:
state->n_wronly--;
break;
case FMODE_READ|FMODE_WRITE:
state->n_rdwr--;
}
newstate = FMODE_READ|FMODE_WRITE;
if (state->n_rdwr == 0) {
if (state->n_rdonly == 0) {
newstate &= ~FMODE_READ;
call_close |= test_bit(NFS_O_RDONLY_STATE, &state->flags);
call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
}
if (state->n_wronly == 0) {
newstate &= ~FMODE_WRITE;
call_close |= test_bit(NFS_O_WRONLY_STATE, &state->flags);
call_close |= test_bit(NFS_O_RDWR_STATE, &state->flags);
}
if (newstate == 0)
clear_bit(NFS_DELEGATED_STATE, &state->flags);
}
nfs4_state_set_mode_locked(state, newstate);
spin_unlock(&owner->so_lock);
if (!call_close) {
nfs4_put_open_state(state);
nfs4_put_state_owner(owner);
} else
nfs4_do_close(state, gfp_mask, wait);
}
void nfs4_close_state(struct nfs4_state *state, fmode_t fmode)
{
__nfs4_close(state, fmode, GFP_KERNEL, 0);
}
void nfs4_close_sync(struct nfs4_state *state, fmode_t fmode)
{
__nfs4_close(state, fmode, GFP_KERNEL, 1);
}
/*
* Search the state->lock_states for an existing lock_owner
* that is compatible with either of the given owners.
* If the second is non-zero, then the first refers to a Posix-lock
* owner (current->files) and the second refers to a flock/OFD
* owner (struct file*). In that case, prefer a match for the first
* owner.
* If both sorts of locks are held on the one file we cannot know
* which stateid was intended to be used, so a "correct" choice cannot
* be made. Failing that, a "consistent" choice is preferable. The
* consistent choice we make is to prefer the first owner, that of a
* Posix lock.
*/
static struct nfs4_lock_state *
__nfs4_find_lock_state(struct nfs4_state *state,
fl_owner_t owner, fl_owner_t owner2)
{
struct nfs4_lock_state *pos, *ret = NULL;
list_for_each_entry(pos, &state->lock_states, ls_locks) {
if (pos->ls_owner == owner) {
ret = pos;
break;
}
if (pos->ls_owner == owner2)
ret = pos;
}
if (ret)
refcount_inc(&ret->ls_count);
return ret;
}
/*
* Return a compatible lock_state. If no initialized lock_state structure
* exists, return an uninitialized one.
*
*/
static struct nfs4_lock_state *nfs4_alloc_lock_state(struct nfs4_state *state, fl_owner_t owner)
{
struct nfs4_lock_state *lsp;
struct nfs_server *server = state->owner->so_server;
lsp = kzalloc(sizeof(*lsp), GFP_KERNEL_ACCOUNT);
if (lsp == NULL)
return NULL;
nfs4_init_seqid_counter(&lsp->ls_seqid);
refcount_set(&lsp->ls_count, 1);
lsp->ls_state = state;
lsp->ls_owner = owner;
lsp->ls_seqid.owner_id = atomic64_inc_return(&server->owner_ctr);
INIT_LIST_HEAD(&lsp->ls_locks);
return lsp;
}
void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp)
{
nfs4_destroy_seqid_counter(&lsp->ls_seqid);
kfree(lsp);
}
/*
* Return a compatible lock_state. If no initialized lock_state structure
* exists, return an uninitialized one.
*
*/
static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_owner_t owner)
{
struct nfs4_lock_state *lsp, *new = NULL;
for(;;) {
spin_lock(&state->state_lock);
lsp = __nfs4_find_lock_state(state, owner, NULL);
if (lsp != NULL)
break;
if (new != NULL) {
list_add(&new->ls_locks, &state->lock_states);
set_bit(LK_STATE_IN_USE, &state->flags);
lsp = new;
new = NULL;
break;
}
spin_unlock(&state->state_lock);
new = nfs4_alloc_lock_state(state, owner);
if (new == NULL)
return NULL;
}
spin_unlock(&state->state_lock);
if (new != NULL)
nfs4_free_lock_state(state->owner->so_server, new);
return lsp;
}
/*
* Release reference to lock_state, and free it if we see that
* it is no longer in use
*/
void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
{
struct nfs_server *server;
struct nfs4_state *state;
if (lsp == NULL)
return;
state = lsp->ls_state;
if (!refcount_dec_and_lock(&lsp->ls_count, &state->state_lock))
return;
list_del(&lsp->ls_locks);
if (list_empty(&state->lock_states))
clear_bit(LK_STATE_IN_USE, &state->flags);
spin_unlock(&state->state_lock);
server = state->owner->so_server;
if (test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags)) {
struct nfs_client *clp = server->nfs_client;
clp->cl_mvops->free_lock_state(server, lsp);
} else
nfs4_free_lock_state(server, lsp);
}
static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
{
struct nfs4_lock_state *lsp = src->fl_u.nfs4_fl.owner;
dst->fl_u.nfs4_fl.owner = lsp;
refcount_inc(&lsp->ls_count);
}
static void nfs4_fl_release_lock(struct file_lock *fl)
{
nfs4_put_lock_state(fl->fl_u.nfs4_fl.owner);
}
static const struct file_lock_operations nfs4_fl_lock_ops = {
.fl_copy_lock = nfs4_fl_copy_lock,
.fl_release_private = nfs4_fl_release_lock,
};
int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
{
struct nfs4_lock_state *lsp;
if (fl->fl_ops != NULL)
return 0;
lsp = nfs4_get_lock_state(state, fl->c.flc_owner);
if (lsp == NULL)
return -ENOMEM;
fl->fl_u.nfs4_fl.owner = lsp;
fl->fl_ops = &nfs4_fl_lock_ops;
return 0;
}
static int nfs4_copy_lock_stateid(nfs4_stateid *dst,
struct nfs4_state *state,
const struct nfs_lock_context *l_ctx)
{
struct nfs4_lock_state *lsp;
fl_owner_t owner, fl_flock_owner;
int ret = -ENOENT;
if (l_ctx == NULL)
goto out;
if (test_bit(LK_STATE_IN_USE, &state->flags) == 0)
goto out;
owner = l_ctx->lockowner;
fl_flock_owner = l_ctx->open_context->flock_owner;
spin_lock(&state->state_lock);
lsp = __nfs4_find_lock_state(state, owner, fl_flock_owner);
if (lsp && test_bit(NFS_LOCK_LOST, &lsp->ls_flags))
ret = -EIO;
else if (lsp != NULL && test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags) != 0) {
nfs4_stateid_copy(dst, &lsp->ls_stateid);
ret = 0;
}
spin_unlock(&state->state_lock);
nfs4_put_lock_state(lsp);
out:
return ret;
}
bool nfs4_copy_open_stateid(nfs4_stateid *dst, struct nfs4_state *state)
{
bool ret;
const nfs4_stateid *src;
int seq;
do {
ret = false;
src = &zero_stateid;
seq = read_seqbegin(&state->seqlock);
if (test_bit(NFS_OPEN_STATE, &state->flags)) {
src = &state->open_stateid;
ret = true;
}
nfs4_stateid_copy(dst, src);
} while (read_seqretry(&state->seqlock, seq));
return ret;
}
/*
* Byte-range lock aware utility to initialize the stateid of read/write
* requests.
*/
int nfs4_select_rw_stateid(struct nfs4_state *state,
fmode_t fmode, const struct nfs_lock_context *l_ctx,
nfs4_stateid *dst, const struct cred **cred)
{
int ret;
if (!nfs4_valid_open_stateid(state))
return -EIO;
if (cred != NULL)
*cred = NULL;
ret = nfs4_copy_lock_stateid(dst, state, l_ctx);
if (ret == -EIO)
/* A lost lock - don't even consider delegations */
goto out;
/* returns true if delegation stateid found and copied */
if (nfs4_copy_delegation_stateid(state->inode, fmode, dst, cred)) {
ret = 0;
goto out;
}
if (ret != -ENOENT)
/* nfs4_copy_delegation_stateid() didn't over-write
* dst, so it still has the lock stateid which we now
* choose to use.
*/
goto out;
ret = nfs4_copy_open_stateid(dst, state) ? 0 : -EAGAIN;
out:
if (nfs_server_capable(state->inode, NFS_CAP_STATEID_NFSV41))
dst->seqid = 0;
return ret;
}
struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
{
struct nfs_seqid *new;
new = kmalloc(sizeof(*new), gfp_mask);
if (new == NULL)
return ERR_PTR(-ENOMEM);
new->sequence = counter;
INIT_LIST_HEAD(&new->list);
new->task = NULL;
return new;
}
void nfs_release_seqid(struct nfs_seqid *seqid)
{
struct nfs_seqid_counter *sequence;
if (seqid == NULL || list_empty(&seqid->list))
return;
sequence = seqid->sequence;
spin_lock(&sequence->lock);
list_del_init(&seqid->list);
if (!list_empty(&sequence->list)) {
struct nfs_seqid *next;
next = list_first_entry(&sequence->list,
struct nfs_seqid, list);
rpc_wake_up_queued_task(&sequence->wait, next->task);
}
spin_unlock(&sequence->lock);
}
void nfs_free_seqid(struct nfs_seqid *seqid)
{
nfs_release_seqid(seqid);
kfree(seqid);
}
/*
* Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
* failed with a seqid incrementing error -
* see comments nfs4.h:seqid_mutating_error()
*/
static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
{
switch (status) {
case 0:
break;
case -NFS4ERR_BAD_SEQID:
if (seqid->sequence->flags & NFS_SEQID_CONFIRMED)
return;
pr_warn_ratelimited("NFS: v4 server returned a bad"
" sequence-id error on an"
" unconfirmed sequence %p!\n",
seqid->sequence);
return;
case -NFS4ERR_STALE_CLIENTID:
case -NFS4ERR_STALE_STATEID:
case -NFS4ERR_BAD_STATEID:
case -NFS4ERR_BADXDR:
case -NFS4ERR_RESOURCE:
case -NFS4ERR_NOFILEHANDLE:
case -NFS4ERR_MOVED:
/* Non-seqid mutating errors */
return;
}
/*
* Note: no locking needed as we are guaranteed to be first
* on the sequence list
*/
seqid->sequence->counter++;
}
void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
{
struct nfs4_state_owner *sp;
if (seqid == NULL)
return;
sp = container_of(seqid->sequence, struct nfs4_state_owner, so_seqid);
if (status == -NFS4ERR_BAD_SEQID)
nfs4_reset_state_owner(sp);
if (!nfs4_has_session(sp->so_server->nfs_client))
nfs_increment_seqid(status, seqid);
}
/*
* Increment the seqid if the LOCK/LOCKU succeeded, or
* failed with a seqid incrementing error -
* see comments nfs4.h:seqid_mutating_error()
*/
void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
{
if (seqid != NULL)
nfs_increment_seqid(status, seqid);
}
int nfs_wait_on_sequence(struct nfs_seqid *seqid, struct rpc_task *task)
{
struct nfs_seqid_counter *sequence;
int status = 0;
if (seqid == NULL)
goto out;
sequence = seqid->sequence;
spin_lock(&sequence->lock);
seqid->task = task;
if (list_empty(&seqid->list))
list_add_tail(&seqid->list, &sequence->list);
if (list_first_entry(&sequence->list, struct nfs_seqid, list) == seqid)
goto unlock;
rpc_sleep_on(&sequence->wait, task, NULL);
status = -EAGAIN;
unlock:
spin_unlock(&sequence->lock);
out:
return status;
}
static int nfs4_run_state_manager(void *);
static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
{
clear_and_wake_up_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
rpc_wake_up(&clp->cl_rpcwaitq);
}
/*
* Schedule the nfs_client asynchronous state management routine
*/
void nfs4_schedule_state_manager(struct nfs_client *clp)
{
struct task_struct *task;
char buf[INET6_ADDRSTRLEN + sizeof("-manager") + 1];
struct rpc_clnt *clnt = clp->cl_rpcclient;
bool swapon = false;
if (clnt->cl_shutdown)
return;
set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state);
if (atomic_read(&clnt->cl_swapper)) {
swapon = !test_and_set_bit(NFS4CLNT_MANAGER_AVAILABLE,
&clp->cl_state);
if (!swapon) {
wake_up_var(&clp->cl_state);
return;
}
}
if (test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) != 0)
return;
__module_get(THIS_MODULE);
refcount_inc(&clp->cl_count);
/* The rcu_read_lock() is not strictly necessary, as the state
* manager is the only thread that ever changes the rpc_xprt
* after it's initialized. At this point, we're single threaded. */
rcu_read_lock();
snprintf(buf, sizeof(buf), "%s-manager",
rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
rcu_read_unlock();
task = kthread_run(nfs4_run_state_manager, clp, "%s", buf);
if (IS_ERR(task)) {
printk(KERN_ERR "%s: kthread_run: %ld\n",
__func__, PTR_ERR(task));
if (!nfs_client_init_is_complete(clp))
nfs_mark_client_ready(clp, PTR_ERR(task));
if (swapon)
clear_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state);
nfs4_clear_state_manager_bit(clp);
nfs_put_client(clp);
module_put(THIS_MODULE);
}
}
/*
* Schedule a lease recovery attempt
*/
void nfs4_schedule_lease_recovery(struct nfs_client *clp)
{
if (!clp)
return;
if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
dprintk("%s: scheduling lease recovery for server %s\n", __func__,
clp->cl_hostname);
nfs4_schedule_state_manager(clp);
}
EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery);
/**
* nfs4_schedule_migration_recovery - trigger migration recovery
*
* @server: FSID that is migrating
*
* Returns zero if recovery has started, otherwise a negative NFS4ERR
* value is returned.
*/
int nfs4_schedule_migration_recovery(const struct nfs_server *server)
{
struct nfs_client *clp = server->nfs_client;
if (server->fh_expire_type != NFS4_FH_PERSISTENT) {
pr_err("NFS: volatile file handles not supported (server %s)\n",
clp->cl_hostname);
return -NFS4ERR_IO;
}
if (test_bit(NFS_MIG_FAILED, &server->mig_status))
return -NFS4ERR_IO;
dprintk("%s: scheduling migration recovery for (%llx:%llx) on %s\n",
__func__,
(unsigned long long)server->fsid.major,
(unsigned long long)server->fsid.minor,
clp->cl_hostname);
set_bit(NFS_MIG_IN_TRANSITION,
&((struct nfs_server *)server)->mig_status);
set_bit(NFS4CLNT_MOVED, &clp->cl_state);
nfs4_schedule_state_manager(clp);
return 0;
}
EXPORT_SYMBOL_GPL(nfs4_schedule_migration_recovery);
/**
* nfs4_schedule_lease_moved_recovery - start lease-moved recovery
*
* @clp: server to check for moved leases
*
*/
void nfs4_schedule_lease_moved_recovery(struct nfs_client *clp)
{
dprintk("%s: scheduling lease-moved recovery for client ID %llx on %s\n",
__func__, clp->cl_clientid, clp->cl_hostname);
set_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state);
nfs4_schedule_state_manager(clp);
}
EXPORT_SYMBOL_GPL(nfs4_schedule_lease_moved_recovery);
int nfs4_wait_clnt_recover(struct nfs_client *clp)
{
int res;
might_sleep();
refcount_inc(&clp->cl_count);
res = wait_on_bit_action(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING,
nfs_wait_bit_killable,
TASK_KILLABLE|TASK_FREEZABLE_UNSAFE);
if (res)
goto out;
if (clp->cl_cons_state < 0)
res = clp->cl_cons_state;
out:
nfs_put_client(clp);
return res;
}
int nfs4_client_recover_expired_lease(struct nfs_client *clp)
{
unsigned int loop;
int ret;
for (loop = NFS4_MAX_LOOP_ON_RECOVER; loop != 0; loop--) {
ret = nfs4_wait_clnt_recover(clp);
if (ret != 0)
break;
if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) &&
!test_bit(NFS4CLNT_CHECK_LEASE,&clp->cl_state))
break;
nfs4_schedule_state_manager(clp);
ret = -EIO;
}
return ret;
}
/*
* nfs40_handle_cb_pathdown - return all delegations after NFS4ERR_CB_PATH_DOWN
* @clp: client to process
*
* Set the NFS4CLNT_LEASE_EXPIRED state in order to force a
* resend of the SETCLIENTID and hence re-establish the
* callback channel. Then return all existing delegations.
*/
static void nfs40_handle_cb_pathdown(struct nfs_client *clp)
{
set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
nfs_expire_all_delegations(clp);
dprintk("%s: handling CB_PATHDOWN recovery for server %s\n", __func__,
clp->cl_hostname);
}
void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
{
nfs40_handle_cb_pathdown(clp);
nfs4_schedule_state_manager(clp);
}
static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
{
if (!nfs4_valid_open_stateid(state))
return 0;
set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
/* Don't recover state that expired before the reboot */
if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
return 0;
}
set_bit(NFS_OWNER_RECLAIM_REBOOT, &state->owner->so_flags);
set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
return 1;
}
int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
{
if (!nfs4_valid_open_stateid(state))
return 0;
set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
set_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
return 1;
}
int nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
{
struct nfs_client *clp = server->nfs_client;
if (!nfs4_state_mark_reclaim_nograce(clp, state))
return -EBADF;
nfs_inode_find_delegation_state_and_recover(state->inode,
&state->stateid);
dprintk("%s: scheduling stateid recovery for server %s\n", __func__,
clp->cl_hostname);
nfs4_schedule_state_manager(clp);
return 0;
}
EXPORT_SYMBOL_GPL(nfs4_schedule_stateid_recovery);
static struct nfs4_lock_state *
nfs_state_find_lock_state_by_stateid(struct nfs4_state *state,
const nfs4_stateid *stateid)
{
struct nfs4_lock_state *pos;
list_for_each_entry(pos, &state->lock_states, ls_locks) {
if (!test_bit(NFS_LOCK_INITIALIZED, &pos->ls_flags))
continue;
if (nfs4_stateid_match_or_older(&pos->ls_stateid, stateid))
return pos;
}
return NULL;
}
static bool nfs_state_lock_state_matches_stateid(struct nfs4_state *state,
const nfs4_stateid *stateid)
{
bool found = false;
if (test_bit(LK_STATE_IN_USE, &state->flags)) {
spin_lock(&state->state_lock);
if (nfs_state_find_lock_state_by_stateid(state, stateid))
found = true;
spin_unlock(&state->state_lock);
}
return found;
}
void nfs_inode_find_state_and_recover(struct inode *inode,
const nfs4_stateid *stateid)
{
struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs_open_context *ctx;
struct nfs4_state *state;
bool found = false;
rcu_read_lock();
list_for_each_entry_rcu(ctx, &nfsi->open_files, list) {
state = ctx->state;
if (state == NULL)
continue;
if (nfs4_stateid_match_or_older(&state->stateid, stateid) &&
nfs4_state_mark_reclaim_nograce(clp, state)) {
found = true;
continue;
}
if (test_bit(NFS_OPEN_STATE, &state->flags) &&
nfs4_stateid_match_or_older(&state->open_stateid, stateid) &&
nfs4_state_mark_reclaim_nograce(clp, state)) {
found = true;
continue;
}
if (nfs_state_lock_state_matches_stateid(state, stateid) &&
nfs4_state_mark_reclaim_nograce(clp, state))
found = true;
}
rcu_read_unlock();
nfs_inode_find_delegation_state_and_recover(inode, stateid);
if (found)
nfs4_schedule_state_manager(clp);
}
static void nfs4_state_mark_open_context_bad(struct nfs4_state *state, int err)
{
struct inode *inode = state->inode;
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs_open_context *ctx;
rcu_read_lock();
list_for_each_entry_rcu(ctx, &nfsi->open_files, list) {
if (ctx->state != state)
continue;
set_bit(NFS_CONTEXT_BAD, &ctx->flags);
pr_warn("NFSv4: state recovery failed for open file %pd2, "
"error = %d\n", ctx->dentry, err);
}
rcu_read_unlock();
}
static void nfs4_state_mark_recovery_failed(struct nfs4_state *state, int error)
{
set_bit(NFS_STATE_RECOVERY_FAILED, &state->flags);
nfs4_state_mark_open_context_bad(state, error);
}
static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
{
struct inode *inode = state->inode;
struct nfs_inode *nfsi = NFS_I(inode);
struct file_lock *fl;
struct nfs4_lock_state *lsp;
int status = 0;
struct file_lock_context *flctx = locks_inode_context(inode);
struct list_head *list;
if (flctx == NULL)
return 0;
list = &flctx->flc_posix;
/* Guard against delegation returns and new lock/unlock calls */
down_write(&nfsi->rwsem);
spin_lock(&flctx->flc_lock);
restart:
for_each_file_lock(fl, list) {
if (nfs_file_open_context(fl->c.flc_file)->state != state)
continue;
spin_unlock(&flctx->flc_lock);
status = ops->recover_lock(state, fl);
switch (status) {
case 0:
break;
case -ETIMEDOUT:
case -ESTALE:
case -NFS4ERR_ADMIN_REVOKED:
case -NFS4ERR_STALE_STATEID:
case -NFS4ERR_BAD_STATEID:
case -NFS4ERR_EXPIRED:
case -NFS4ERR_NO_GRACE:
case -NFS4ERR_STALE_CLIENTID:
case -NFS4ERR_BADSESSION:
case -NFS4ERR_BADSLOT:
case -NFS4ERR_BAD_HIGH_SLOT:
case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
goto out;
default:
pr_err("NFS: %s: unhandled error %d\n",
__func__, status);
fallthrough;
case -ENOMEM:
case -NFS4ERR_DENIED:
case -NFS4ERR_RECLAIM_BAD:
case -NFS4ERR_RECLAIM_CONFLICT:
lsp = fl->fl_u.nfs4_fl.owner;
if (lsp)
set_bit(NFS_LOCK_LOST, &lsp->ls_flags);
status = 0;
}
spin_lock(&flctx->flc_lock);
}
if (list == &flctx->flc_posix) {
list = &flctx->flc_flock;
goto restart;
}
spin_unlock(&flctx->flc_lock);
out:
up_write(&nfsi->rwsem);
return status;
}
#ifdef CONFIG_NFS_V4_2
static void nfs42_complete_copies(struct nfs4_state_owner *sp, struct nfs4_state *state)
{
struct nfs4_copy_state *copy;
if (!test_bit(NFS_CLNT_DST_SSC_COPY_STATE, &state->flags) &&
!test_bit(NFS_CLNT_SRC_SSC_COPY_STATE, &state->flags))
return;
spin_lock(&sp->so_server->nfs_client->cl_lock);
list_for_each_entry(copy, &sp->so_server->ss_copies, copies) {
if ((test_bit(NFS_CLNT_DST_SSC_COPY_STATE, &state->flags) &&
!nfs4_stateid_match_other(&state->stateid,
&copy->parent_dst_state->stateid)))
continue;
copy->flags = 1;
if (test_and_clear_bit(NFS_CLNT_DST_SSC_COPY_STATE,
&state->flags)) {
clear_bit(NFS_CLNT_SRC_SSC_COPY_STATE, &state->flags);
complete(&copy->completion);
}
}
list_for_each_entry(copy, &sp->so_server->ss_src_copies, src_copies) {
if ((test_bit(NFS_CLNT_SRC_SSC_COPY_STATE, &state->flags) &&
!nfs4_stateid_match_other(&state->stateid,
&copy->parent_src_state->stateid)))
continue;
copy->flags = 1;
if (test_and_clear_bit(NFS_CLNT_DST_SSC_COPY_STATE,
&state->flags))
complete(&copy->completion);
}
spin_unlock(&sp->so_server->nfs_client->cl_lock);
}
#else /* !CONFIG_NFS_V4_2 */
static inline void nfs42_complete_copies(struct nfs4_state_owner *sp,
struct nfs4_state *state)
{
}
#endif /* CONFIG_NFS_V4_2 */
static int __nfs4_reclaim_open_state(struct nfs4_state_owner *sp, struct nfs4_state *state,
const struct nfs4_state_recovery_ops *ops,
int *lost_locks)
{
struct nfs4_lock_state *lock;
int status;
status = ops->recover_open(sp, state);
if (status < 0)
return status;
status = nfs4_reclaim_locks(state, ops);
if (status < 0)
return status;
if (!test_bit(NFS_DELEGATED_STATE, &state->flags)) {
spin_lock(&state->state_lock);
list_for_each_entry(lock, &state->lock_states, ls_locks) {
trace_nfs4_state_lock_reclaim(state, lock);
if (!test_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags) &&
!test_bit(NFS_LOCK_UNLOCKING, &lock->ls_flags))
*lost_locks += 1;
}
spin_unlock(&state->state_lock);
}
nfs42_complete_copies(sp, state);
clear_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
return status;
}
static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp,
const struct nfs4_state_recovery_ops *ops,
int *lost_locks)
{
struct nfs4_state *state;
unsigned int loop = 0;
int status = 0;
#ifdef CONFIG_NFS_V4_2
bool found_ssc_copy_state = false;
#endif /* CONFIG_NFS_V4_2 */
/* Note: we rely on the sp->so_states list being ordered
* so that we always reclaim open(O_RDWR) and/or open(O_WRITE)
* states first.
* This is needed to ensure that the server won't give us any
* read delegations that we have to return if, say, we are
* recovering after a network partition or a reboot from a
* server that doesn't support a grace period.
*/
spin_lock(&sp->so_lock);
restart:
list_for_each_entry(state, &sp->so_states, open_states) {
if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
continue;
if (!nfs4_valid_open_stateid(state))
continue;
if (state->state == 0)
continue;
#ifdef CONFIG_NFS_V4_2
if (test_bit(NFS_SRV_SSC_COPY_STATE, &state->flags)) {
nfs4_state_mark_recovery_failed(state, -EIO);
found_ssc_copy_state = true;
continue;
}
#endif /* CONFIG_NFS_V4_2 */
refcount_inc(&state->count);
spin_unlock(&sp->so_lock);
status = __nfs4_reclaim_open_state(sp, state, ops, lost_locks);
switch (status) {
default:
if (status >= 0) {
loop = 0;
break;
}
printk(KERN_ERR "NFS: %s: unhandled error %d\n", __func__, status);
fallthrough;
case -ENOENT:
case -ENOMEM:
case -EACCES:
case -EROFS:
case -EIO:
case -ESTALE:
/* Open state on this file cannot be recovered */
nfs4_state_mark_recovery_failed(state, status);
break;
case -EAGAIN:
ssleep(1);
if (loop++ < 10) {
set_bit(ops->state_flag_bit, &state->flags);
break;
}
fallthrough;
case -NFS4ERR_ADMIN_REVOKED:
case -NFS4ERR_STALE_STATEID:
case -NFS4ERR_OLD_STATEID:
case -NFS4ERR_BAD_STATEID:
case -NFS4ERR_RECLAIM_BAD:
case -NFS4ERR_RECLAIM_CONFLICT:
nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
break;
case -NFS4ERR_EXPIRED:
case -NFS4ERR_NO_GRACE:
nfs4_state_mark_reclaim_nograce(sp->so_server->nfs_client, state);
fallthrough;
case -NFS4ERR_STALE_CLIENTID:
case -NFS4ERR_BADSESSION:
case -NFS4ERR_BADSLOT:
case -NFS4ERR_BAD_HIGH_SLOT:
case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
case -ETIMEDOUT:
goto out_err;
}
nfs4_put_open_state(state);
spin_lock(&sp->so_lock);
goto restart;
}
spin_unlock(&sp->so_lock);
#ifdef CONFIG_NFS_V4_2
if (found_ssc_copy_state)
return -EIO;
#endif /* CONFIG_NFS_V4_2 */
return 0;
out_err:
nfs4_put_open_state(state);
spin_lock(&sp->so_lock);
spin_unlock(&sp->so_lock);
return status;
}
static void nfs4_clear_open_state(struct nfs4_state *state)
{
struct nfs4_lock_state *lock;
clear_bit(NFS_DELEGATED_STATE, &state->flags);
clear_bit(NFS_O_RDONLY_STATE, &state->flags);
clear_bit(NFS_O_WRONLY_STATE, &state->flags);
clear_bit(NFS_O_RDWR_STATE, &state->flags);
spin_lock(&state->state_lock);
list_for_each_entry(lock, &state->lock_states, ls_locks) {
lock->ls_seqid.flags = 0;
clear_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags);
}
spin_unlock(&state->state_lock);
}
static void nfs4_reset_seqids(struct nfs_server *server,
int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
{
struct nfs_client *clp = server->nfs_client;
struct nfs4_state_owner *sp;
struct rb_node *pos;
struct nfs4_state *state;
spin_lock(&clp->cl_lock);
for (pos = rb_first(&server->state_owners);
pos != NULL;
pos = rb_next(pos)) {
sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
sp->so_seqid.flags = 0;
spin_lock(&sp->so_lock);
list_for_each_entry(state, &sp->so_states, open_states) {
if (mark_reclaim(clp, state))
nfs4_clear_open_state(state);
}
spin_unlock(&sp->so_lock);
}
spin_unlock(&clp->cl_lock);
}
static void nfs4_state_mark_reclaim_helper(struct nfs_client *clp,
int (*mark_reclaim)(struct nfs_client *clp, struct nfs4_state *state))
{
struct nfs_server *server;
rcu_read_lock();
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
nfs4_reset_seqids(server, mark_reclaim);
rcu_read_unlock();
}
static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
{
set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
/* Mark all delegations for reclaim */
nfs_delegation_mark_reclaim(clp);
nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
}
static int nfs4_reclaim_complete(struct nfs_client *clp,
const struct nfs4_state_recovery_ops *ops,
const struct cred *cred)
{
/* Notify the server we're done reclaiming our state */
if (ops->reclaim_complete)
return ops->reclaim_complete(clp, cred);
return 0;
}
static void nfs4_clear_reclaim_server(struct nfs_server *server)
{
struct nfs_client *clp = server->nfs_client;
struct nfs4_state_owner *sp;
struct rb_node *pos;
struct nfs4_state *state;
spin_lock(&clp->cl_lock);
for (pos = rb_first(&server->state_owners);
pos != NULL;
pos = rb_next(pos)) {
sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
spin_lock(&sp->so_lock);
list_for_each_entry(state, &sp->so_states, open_states) {
if (!test_and_clear_bit(NFS_STATE_RECLAIM_REBOOT,
&state->flags))
continue;
nfs4_state_mark_reclaim_nograce(clp, state);
}
spin_unlock(&sp->so_lock);
}
spin_unlock(&clp->cl_lock);
}
static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
{
struct nfs_server *server;
if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
return 0;
rcu_read_lock();
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
nfs4_clear_reclaim_server(server);
rcu_read_unlock();
nfs_delegation_reap_unclaimed(clp);
return 1;
}
static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
{
const struct nfs4_state_recovery_ops *ops;
const struct cred *cred;
int err;
if (!nfs4_state_clear_reclaim_reboot(clp))
return;
pnfs_destroy_all_layouts(clp);
ops = clp->cl_mvops->reboot_recovery_ops;
cred = nfs4_get_clid_cred(clp);
err = nfs4_reclaim_complete(clp, ops, cred);
put_cred(cred);
if (err == -NFS4ERR_CONN_NOT_BOUND_TO_SESSION)
set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
}
static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
{
nfs_mark_test_expired_all_delegations(clp);
nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
}
static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
{
switch (error) {
case 0:
break;
case -NFS4ERR_CB_PATH_DOWN:
nfs40_handle_cb_pathdown(clp);
break;
case -NFS4ERR_NO_GRACE:
nfs4_state_end_reclaim_reboot(clp);
break;
case -NFS4ERR_STALE_CLIENTID:
set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
nfs4_state_start_reclaim_reboot(clp);
break;
case -NFS4ERR_EXPIRED:
set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
nfs4_state_start_reclaim_nograce(clp);
break;
case -NFS4ERR_BADSESSION:
case -NFS4ERR_BADSLOT:
case -NFS4ERR_BAD_HIGH_SLOT:
case -NFS4ERR_DEADSESSION:
case -NFS4ERR_SEQ_FALSE_RETRY:
case -NFS4ERR_SEQ_MISORDERED:
set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
/* Zero session reset errors */
break;
case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
break;
default:
dprintk("%s: failed to handle error %d for server %s\n",
__func__, error, clp->cl_hostname);
return error;
}
dprintk("%s: handled error %d for server %s\n", __func__, error,
clp->cl_hostname);
return 0;
}
static int nfs4_do_reclaim(struct nfs_client *clp, const struct nfs4_state_recovery_ops *ops)
{
struct nfs4_state_owner *sp;
struct nfs_server *server;
struct rb_node *pos;
LIST_HEAD(freeme);
int lost_locks = 0;
int status;
status = nfs4_begin_drain_session(clp);
if (status < 0)
return status;
restart:
rcu_read_lock();
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
nfs4_purge_state_owners(server, &freeme);
spin_lock(&clp->cl_lock);
for (pos = rb_first(&server->state_owners);
pos != NULL;
pos = rb_next(pos)) {
sp = rb_entry(pos,
struct nfs4_state_owner, so_server_node);
if (!test_and_clear_bit(ops->owner_flag_bit,
&sp->so_flags))
continue;
if (!atomic_inc_not_zero(&sp->so_count))
continue;
spin_unlock(&clp->cl_lock);
rcu_read_unlock();
status = nfs4_reclaim_open_state(sp, ops, &lost_locks);
if (status < 0) {
if (lost_locks)
pr_warn("NFS: %s: lost %d locks\n",
clp->cl_hostname, lost_locks);
set_bit(ops->owner_flag_bit, &sp->so_flags);
nfs4_put_state_owner(sp);
status = nfs4_recovery_handle_error(clp, status);
nfs4_free_state_owners(&freeme);
return (status != 0) ? status : -EAGAIN;
}
nfs4_put_state_owner(sp);
goto restart;
}
spin_unlock(&clp->cl_lock);
}
rcu_read_unlock();
nfs4_free_state_owners(&freeme);
if (lost_locks)
pr_warn("NFS: %s: lost %d locks\n",
clp->cl_hostname, lost_locks);
return 0;
}
static int nfs4_check_lease(struct nfs_client *clp)
{
const struct cred *cred;
const struct nfs4_state_maintenance_ops *ops =
clp->cl_mvops->state_renewal_ops;
int status;
/* Is the client already known to have an expired lease? */
if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
return 0;
cred = ops->get_state_renewal_cred(clp);
if (cred == NULL) {
cred = nfs4_get_clid_cred(clp);
status = -ENOKEY;
if (cred == NULL)
goto out;
}
status = ops->renew_lease(clp, cred);
put_cred(cred);
if (status == -ETIMEDOUT) {
set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
return 0;
}
out:
return nfs4_recovery_handle_error(clp, status);
}
/* Set NFS4CLNT_LEASE_EXPIRED and reclaim reboot state for all v4.0 errors
* and for recoverable errors on EXCHANGE_ID for v4.1
*/
static int nfs4_handle_reclaim_lease_error(struct nfs_client *clp, int status)
{
switch (status) {
case -NFS4ERR_SEQ_MISORDERED:
if (test_and_set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state))
return -ESERVERFAULT;
/* Lease confirmation error: retry after purging the lease */
ssleep(1);
clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
break;
case -NFS4ERR_STALE_CLIENTID:
clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
nfs4_state_start_reclaim_reboot(clp);
break;
case -NFS4ERR_CLID_INUSE:
pr_err("NFS: Server %s reports our clientid is in use\n",
clp->cl_hostname);
nfs_mark_client_ready(clp, -EPERM);
clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
return -EPERM;
case -ETIMEDOUT:
if (clp->cl_cons_state == NFS_CS_SESSION_INITING) {
nfs_mark_client_ready(clp, -EIO);
return -EIO;
}
fallthrough;
case -EACCES:
case -NFS4ERR_DELAY:
case -EAGAIN:
ssleep(1);
break;
case -NFS4ERR_MINOR_VERS_MISMATCH:
if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
nfs_mark_client_ready(clp, -EPROTONOSUPPORT);
dprintk("%s: exit with error %d for server %s\n",
__func__, -EPROTONOSUPPORT, clp->cl_hostname);
return -EPROTONOSUPPORT;
case -ENOSPC:
if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
nfs_mark_client_ready(clp, -EIO);
return -EIO;
case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
* in nfs4_exchange_id */
default:
dprintk("%s: exit with error %d for server %s\n", __func__,
status, clp->cl_hostname);
return status;
}
set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
dprintk("%s: handled error %d for server %s\n", __func__, status,
clp->cl_hostname);
return 0;
}
static int nfs4_establish_lease(struct nfs_client *clp)
{
const struct cred *cred;
const struct nfs4_state_recovery_ops *ops =
clp->cl_mvops->reboot_recovery_ops;
int status;
status = nfs4_begin_drain_session(clp);
if (status != 0)
return status;
cred = nfs4_get_clid_cred(clp);
if (cred == NULL)
return -ENOENT;
status = ops->establish_clid(clp, cred);
put_cred(cred);
if (status != 0)
return status;
return 0;
}
/*
* Returns zero or a negative errno. NFS4ERR values are converted
* to local errno values.
*/
static int nfs4_reclaim_lease(struct nfs_client *clp)
{
int status;
status = nfs4_establish_lease(clp);
if (status < 0)
return nfs4_handle_reclaim_lease_error(clp, status);
if (test_and_clear_bit(NFS4CLNT_SERVER_SCOPE_MISMATCH, &clp->cl_state))
nfs4_state_start_reclaim_nograce(clp);
if (!test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
clear_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
return 0;
}
static int nfs4_purge_lease(struct nfs_client *clp)
{
int status;
status = nfs4_establish_lease(clp);
if (status < 0)
return nfs4_handle_reclaim_lease_error(clp, status);
clear_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
nfs4_state_start_reclaim_nograce(clp);
return 0;
}
/*
* Try remote migration of one FSID from a source server to a
* destination server. The source server provides a list of
* potential destinations.
*
* Returns zero or a negative NFS4ERR status code.
*/
static int nfs4_try_migration(struct nfs_server *server, const struct cred *cred)
{
struct nfs_client *clp = server->nfs_client;
struct nfs4_fs_locations *locations = NULL;
struct nfs_fattr *fattr;
struct inode *inode;
struct page *page;
int status, result;
dprintk("--> %s: FSID %llx:%llx on \"%s\"\n", __func__,
(unsigned long long)server->fsid.major,
(unsigned long long)server->fsid.minor,
clp->cl_hostname);
page = alloc_page(GFP_KERNEL);
locations = kmalloc(sizeof(struct nfs4_fs_locations), GFP_KERNEL);
fattr = nfs_alloc_fattr();
if (page == NULL || locations == NULL || fattr == NULL) {
dprintk("<-- %s: no memory\n", __func__);
result = 0;
goto out;
}
locations->fattr = fattr;
inode = d_inode(server->super->s_root);
result = nfs4_proc_get_locations(server, NFS_FH(inode), locations,
page, cred);
if (result) {
dprintk("<-- %s: failed to retrieve fs_locations: %d\n",
__func__, result);
goto out;
}
result = -NFS4ERR_NXIO;
if (!locations->nlocations)
goto out;
if (!(locations->fattr->valid & NFS_ATTR_FATTR_V4_LOCATIONS)) {
dprintk("<-- %s: No fs_locations data, migration skipped\n",
__func__);
goto out;
}
status = nfs4_begin_drain_session(clp);
if (status != 0) {
result = status;
goto out;
}
status = nfs4_replace_transport(server, locations);
if (status != 0) {
dprintk("<-- %s: failed to replace transport: %d\n",
__func__, status);
goto out;
}
result = 0;
dprintk("<-- %s: migration succeeded\n", __func__);
out:
if (page != NULL)
__free_page(page);
if (locations != NULL)
kfree(locations->fattr);
kfree(locations);
if (result) {
pr_err("NFS: migration recovery failed (server %s)\n",
clp->cl_hostname);
set_bit(NFS_MIG_FAILED, &server->mig_status);
}
return result;
}
/*
* Returns zero or a negative NFS4ERR status code.
*/
static int nfs4_handle_migration(struct nfs_client *clp)
{
const struct nfs4_state_maintenance_ops *ops =
clp->cl_mvops->state_renewal_ops;
struct nfs_server *server;
const struct cred *cred;
dprintk("%s: migration reported on \"%s\"\n", __func__,
clp->cl_hostname);
cred = ops->get_state_renewal_cred(clp);
if (cred == NULL)
return -NFS4ERR_NOENT;
clp->cl_mig_gen++;
restart:
rcu_read_lock();
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
int status;
if (server->mig_gen == clp->cl_mig_gen)
continue;
server->mig_gen = clp->cl_mig_gen;
if (!test_and_clear_bit(NFS_MIG_IN_TRANSITION,
&server->mig_status))
continue;
rcu_read_unlock();
status = nfs4_try_migration(server, cred);
if (status < 0) {
put_cred(cred);
return status;
}
goto restart;
}
rcu_read_unlock();
put_cred(cred);
return 0;
}
/*
* Test each nfs_server on the clp's cl_superblocks list to see
* if it's moved to another server. Stop when the server no longer
* returns NFS4ERR_LEASE_MOVED.
*/
static int nfs4_handle_lease_moved(struct nfs_client *clp)
{
const struct nfs4_state_maintenance_ops *ops =
clp->cl_mvops->state_renewal_ops;
struct nfs_server *server;
const struct cred *cred;
dprintk("%s: lease moved reported on \"%s\"\n", __func__,
clp->cl_hostname);
cred = ops->get_state_renewal_cred(clp);
if (cred == NULL)
return -NFS4ERR_NOENT;
clp->cl_mig_gen++;
restart:
rcu_read_lock();
list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
struct inode *inode;
int status;
if (server->mig_gen == clp->cl_mig_gen)
continue;
server->mig_gen = clp->cl_mig_gen;
rcu_read_unlock();
inode = d_inode(server->super->s_root);
status = nfs4_proc_fsid_present(inode, cred);
if (status != -NFS4ERR_MOVED)
goto restart; /* wasn't this one */
if (nfs4_try_migration(server, cred) == -NFS4ERR_LEASE_MOVED)
goto restart; /* there are more */
goto out;
}
rcu_read_unlock();
out:
put_cred(cred);
return 0;
}
/**
* nfs4_discover_server_trunking - Detect server IP address trunking
*
* @clp: nfs_client under test
* @result: OUT: found nfs_client, or clp
*
* Returns zero or a negative errno. If zero is returned,
* an nfs_client pointer is planted in "result".
*
* Note: since we are invoked in process context, and
* not from inside the state manager, we cannot use
* nfs4_handle_reclaim_lease_error().
*/
int nfs4_discover_server_trunking(struct nfs_client *clp,
struct nfs_client **result)
{
const struct nfs4_state_recovery_ops *ops =
clp->cl_mvops->reboot_recovery_ops;
struct rpc_clnt *clnt;
const struct cred *cred;
int i, status;
dprintk("NFS: %s: testing '%s'\n", __func__, clp->cl_hostname);
clnt = clp->cl_rpcclient;
i = 0;
mutex_lock(&nfs_clid_init_mutex);
again:
status = -ENOENT;
cred = nfs4_get_clid_cred(clp);
if (cred == NULL)
goto out_unlock;
status = ops->detect_trunking(clp, result, cred);
put_cred(cred);
switch (status) {
case 0:
case -EINTR:
case -ERESTARTSYS:
break;
case -ETIMEDOUT:
if (clnt->cl_softrtry)
break;
fallthrough;
case -NFS4ERR_DELAY:
case -EAGAIN:
ssleep(1);
fallthrough;
case -NFS4ERR_STALE_CLIENTID:
dprintk("NFS: %s after status %d, retrying\n",
__func__, status);
goto again;
case -EACCES:
if (i++ == 0) {
nfs4_root_machine_cred(clp);
goto again;
}
if (clnt->cl_auth->au_flavor == RPC_AUTH_UNIX)
break;
fallthrough;
case -NFS4ERR_CLID_INUSE:
case -NFS4ERR_WRONGSEC:
/* No point in retrying if we already used RPC_AUTH_UNIX */
if (clnt->cl_auth->au_flavor == RPC_AUTH_UNIX) {
status = -EPERM;
break;
}
clnt = rpc_clone_client_set_auth(clnt, RPC_AUTH_UNIX);
if (IS_ERR(clnt)) {
status = PTR_ERR(clnt);
break;
}
/* Note: this is safe because we haven't yet marked the
* client as ready, so we are the only user of
* clp->cl_rpcclient
*/
clnt = xchg(&clp->cl_rpcclient, clnt);
rpc_shutdown_client(clnt);
clnt = clp->cl_rpcclient;
goto again;
case -NFS4ERR_MINOR_VERS_MISMATCH:
status = -EPROTONOSUPPORT;
break;
case -EKEYEXPIRED:
case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
* in nfs4_exchange_id */
status = -EKEYEXPIRED;
break;
default:
pr_warn("NFS: %s unhandled error %d. Exiting with error EIO\n",
__func__, status);
status = -EIO;
}
out_unlock:
mutex_unlock(&nfs_clid_init_mutex);
dprintk("NFS: %s: status = %d\n", __func__, status);
return status;
}
#ifdef CONFIG_NFS_V4_1
void nfs4_schedule_session_recovery(struct nfs4_session *session, int err)
{
struct nfs_client *clp = session->clp;
switch (err) {
default:
set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
break;
case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
}
nfs4_schedule_state_manager(clp);
}
EXPORT_SYMBOL_GPL(nfs4_schedule_session_recovery);
void nfs41_notify_server(struct nfs_client *clp)
{
/* Use CHECK_LEASE to ping the server with a SEQUENCE */
set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
nfs4_schedule_state_manager(clp);
}
static void nfs4_reset_all_state(struct nfs_client *clp)
{
if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
set_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state);
clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
nfs4_state_start_reclaim_nograce(clp);
dprintk("%s: scheduling reset of all state for server %s!\n",
__func__, clp->cl_hostname);
nfs4_schedule_state_manager(clp);
}
}
static void nfs41_handle_server_reboot(struct nfs_client *clp)
{
if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
nfs4_state_start_reclaim_reboot(clp);
dprintk("%s: server %s rebooted!\n", __func__,
clp->cl_hostname);
nfs4_schedule_state_manager(clp);
}
}
static void nfs41_handle_all_state_revoked(struct nfs_client *clp)
{
nfs4_reset_all_state(clp);
dprintk("%s: state revoked on server %s\n", __func__, clp->cl_hostname);
}
static void nfs41_handle_some_state_revoked(struct nfs_client *clp)
{
nfs4_state_start_reclaim_nograce(clp);
nfs4_schedule_state_manager(clp);
dprintk("%s: state revoked on server %s\n", __func__, clp->cl_hostname);
}
static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
{
/* FIXME: For now, we destroy all layouts. */
pnfs_destroy_all_layouts(clp);
nfs_test_expired_all_delegations(clp);
dprintk("%s: Recallable state revoked on server %s!\n", __func__,
clp->cl_hostname);
}
static void nfs41_handle_backchannel_fault(struct nfs_client *clp)
{
set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
nfs4_schedule_state_manager(clp);
dprintk("%s: server %s declared a backchannel fault\n", __func__,
clp->cl_hostname);
}
static void nfs41_handle_cb_path_down(struct nfs_client *clp)
{
if (test_and_set_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
&clp->cl_state) == 0)
nfs4_schedule_state_manager(clp);
}
void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags,
bool recovery)
{
if (!flags)
return;
dprintk("%s: \"%s\" (client ID %llx) flags=0x%08x\n",
__func__, clp->cl_hostname, clp->cl_clientid, flags);
/*
* If we're called from the state manager thread, then assume we're
* already handling the RECLAIM_NEEDED and/or STATE_REVOKED.
* Those flags are expected to remain set until we're done
* recovering (see RFC5661, section 18.46.3).
*/
if (recovery)
goto out_recovery;
if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
nfs41_handle_server_reboot(clp);
if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED))
nfs41_handle_all_state_revoked(clp);
if (flags & (SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
SEQ4_STATUS_ADMIN_STATE_REVOKED))
nfs41_handle_some_state_revoked(clp);
if (flags & SEQ4_STATUS_LEASE_MOVED)
nfs4_schedule_lease_moved_recovery(clp);
if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
nfs41_handle_recallable_state_revoked(clp);
out_recovery:
if (flags & SEQ4_STATUS_BACKCHANNEL_FAULT)
nfs41_handle_backchannel_fault(clp);
else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
SEQ4_STATUS_CB_PATH_DOWN_SESSION))
nfs41_handle_cb_path_down(clp);
}
static int nfs4_reset_session(struct nfs_client *clp)
{
const struct cred *cred;
int status;
if (!nfs4_has_session(clp))
return 0;
status = nfs4_begin_drain_session(clp);
if (status != 0)
return status;
cred = nfs4_get_clid_cred(clp);
status = nfs4_proc_destroy_session(clp->cl_session, cred);
switch (status) {
case 0:
case -NFS4ERR_BADSESSION:
case -NFS4ERR_DEADSESSION:
break;
case -NFS4ERR_BACK_CHAN_BUSY:
case -NFS4ERR_DELAY:
set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
status = 0;
ssleep(1);
goto out;
default:
status = nfs4_recovery_handle_error(clp, status);
goto out;
}
memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
status = nfs4_proc_create_session(clp, cred);
if (status) {
dprintk("%s: session reset failed with status %d for server %s!\n",
__func__, status, clp->cl_hostname);
status = nfs4_handle_reclaim_lease_error(clp, status);
goto out;
}
nfs41_finish_session_reset(clp);
dprintk("%s: session reset was successful for server %s!\n",
__func__, clp->cl_hostname);
out:
put_cred(cred);
return status;
}
static int nfs4_bind_conn_to_session(struct nfs_client *clp)
{
const struct cred *cred;
int ret;
if (!nfs4_has_session(clp))
return 0;
ret = nfs4_begin_drain_session(clp);
if (ret != 0)
return ret;
cred = nfs4_get_clid_cred(clp);
ret = nfs4_proc_bind_conn_to_session(clp, cred);
put_cred(cred);
clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
switch (ret) {
case 0:
dprintk("%s: bind_conn_to_session was successful for server %s!\n",
__func__, clp->cl_hostname);
break;
case -NFS4ERR_DELAY:
ssleep(1);
set_bit(NFS4CLNT_BIND_CONN_TO_SESSION, &clp->cl_state);
break;
default:
return nfs4_recovery_handle_error(clp, ret);
}
return 0;
}
static void nfs4_layoutreturn_any_run(struct nfs_client *clp)
{
int iomode = 0;
if (test_and_clear_bit(NFS4CLNT_RECALL_ANY_LAYOUT_READ, &clp->cl_state))
iomode += IOMODE_READ;
if (test_and_clear_bit(NFS4CLNT_RECALL_ANY_LAYOUT_RW, &clp->cl_state))
iomode += IOMODE_RW;
/* Note: IOMODE_READ + IOMODE_RW == IOMODE_ANY */
if (iomode) {
pnfs_layout_return_unused_byclid(clp, iomode);
set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state);
}
}
#else /* CONFIG_NFS_V4_1 */
static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
static int nfs4_bind_conn_to_session(struct nfs_client *clp)
{
return 0;
}
static void nfs4_layoutreturn_any_run(struct nfs_client *clp)
{
}
#endif /* CONFIG_NFS_V4_1 */
static void nfs4_state_manager(struct nfs_client *clp)
{
unsigned int memflags;
int status = 0;
const char *section = "", *section_sep = "";
/*
* State recovery can deadlock if the direct reclaim code tries
* start NFS writeback. So ensure memory allocations are all
* GFP_NOFS.
*/
memflags = memalloc_nofs_save();
/* Ensure exclusive access to NFSv4 state */
do {
trace_nfs4_state_mgr(clp);
clear_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state);
if (test_bit(NFS4CLNT_PURGE_STATE, &clp->cl_state)) {
section = "purge state";
status = nfs4_purge_lease(clp);
if (status < 0)
goto out_error;
continue;
}
if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state)) {
section = "lease expired";
/* We're going to have to re-establish a clientid */
status = nfs4_reclaim_lease(clp);
if (status < 0)
goto out_error;
continue;
}
/* Initialize or reset the session */
if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)) {
section = "reset session";
status = nfs4_reset_session(clp);
if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
continue;
if (status < 0)
goto out_error;
}
/* Send BIND_CONN_TO_SESSION */
if (test_and_clear_bit(NFS4CLNT_BIND_CONN_TO_SESSION,
&clp->cl_state)) {
section = "bind conn to session";
status = nfs4_bind_conn_to_session(clp);
if (status < 0)
goto out_error;
continue;
}
if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
section = "check lease";
status = nfs4_check_lease(clp);
if (status < 0)
goto out_error;
continue;
}
if (test_and_clear_bit(NFS4CLNT_MOVED, &clp->cl_state)) {
section = "migration";
status = nfs4_handle_migration(clp);
if (status < 0)
goto out_error;
}
if (test_and_clear_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state)) {
section = "lease moved";
status = nfs4_handle_lease_moved(clp);
if (status < 0)
goto out_error;
}
/* First recover reboot state... */
if (test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {
section = "reclaim reboot";
status = nfs4_do_reclaim(clp,
clp->cl_mvops->reboot_recovery_ops);
if (status == 0)
status = pnfs_layout_handle_reboot(clp);
if (status == -EAGAIN)
continue;
if (status < 0)
goto out_error;
nfs4_state_end_reclaim_reboot(clp);
continue;
}
/* Detect expired delegations... */
if (test_and_clear_bit(NFS4CLNT_DELEGATION_EXPIRED, &clp->cl_state)) {
section = "detect expired delegations";
status = nfs4_begin_drain_session(clp);
if (status < 0)
goto out_error;
nfs_reap_expired_delegations(clp);
continue;
}
/* Now recover expired state... */
if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
section = "reclaim nograce";
status = nfs4_do_reclaim(clp,
clp->cl_mvops->nograce_recovery_ops);
if (status == -EAGAIN)
continue;
if (status < 0)
goto out_error;
clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state);
}
memalloc_nofs_restore(memflags);
nfs4_end_drain_session(clp);
nfs4_clear_state_manager_bit(clp);
if (test_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state) &&
!test_and_set_bit(NFS4CLNT_MANAGER_RUNNING,
&clp->cl_state)) {
memflags = memalloc_nofs_save();
continue;
}
if (!test_and_set_bit(NFS4CLNT_RECALL_RUNNING, &clp->cl_state)) {
if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
nfs_client_return_marked_delegations(clp);
set_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state);
}
nfs4_layoutreturn_any_run(clp);
clear_bit(NFS4CLNT_RECALL_RUNNING, &clp->cl_state);
}
return;
} while (refcount_read(&clp->cl_count) > 1 && !signalled());
goto out_drain;
out_error:
if (strlen(section))
section_sep = ": ";
trace_nfs4_state_mgr_failed(clp, section, status);
pr_warn_ratelimited("NFS: state manager%s%s failed on NFSv4 server %s"
" with error %d\n", section_sep, section,
clp->cl_hostname, -status);
ssleep(1);
out_drain:
memalloc_nofs_restore(memflags);
nfs4_end_drain_session(clp);
nfs4_clear_state_manager_bit(clp);
}
static int nfs4_run_state_manager(void *ptr)
{
struct nfs_client *clp = ptr;
struct rpc_clnt *cl = clp->cl_rpcclient;
while (cl != cl->cl_parent)
cl = cl->cl_parent;
allow_signal(SIGKILL);
again:
nfs4_state_manager(clp);
if (test_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state) &&
!test_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state)) {
wait_var_event_interruptible(&clp->cl_state,
test_bit(NFS4CLNT_RUN_MANAGER,
&clp->cl_state));
if (!atomic_read(&cl->cl_swapper))
clear_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state);
if (refcount_read(&clp->cl_count) > 1 && !signalled() &&
!test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state))
goto again;
/* Either no longer a swapper, or were signalled */
clear_bit(NFS4CLNT_MANAGER_AVAILABLE, &clp->cl_state);
}
if (refcount_read(&clp->cl_count) > 1 && !signalled() &&
test_bit(NFS4CLNT_RUN_MANAGER, &clp->cl_state) &&
!test_and_set_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state))
goto again;
nfs_put_client(clp);
module_put_and_kthread_exit(0);
return 0;
}