885 lines
21 KiB
C
885 lines
21 KiB
C
/*
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* Central processing for nfsd.
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*
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* Authors: Olaf Kirch (okir@monad.swb.de)
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*
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* Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
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*/
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#include <linux/sched/signal.h>
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#include <linux/freezer.h>
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#include <linux/module.h>
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#include <linux/fs_struct.h>
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#include <linux/swap.h>
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#include <linux/sunrpc/stats.h>
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#include <linux/sunrpc/svcsock.h>
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#include <linux/sunrpc/svc_xprt.h>
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#include <linux/lockd/bind.h>
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#include <linux/nfsacl.h>
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#include <linux/seq_file.h>
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#include <linux/inetdevice.h>
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#include <net/addrconf.h>
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#include <net/ipv6.h>
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#include <net/net_namespace.h>
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#include "nfsd.h"
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#include "cache.h"
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#include "vfs.h"
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#include "netns.h"
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#define NFSDDBG_FACILITY NFSDDBG_SVC
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extern struct svc_program nfsd_program;
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static int nfsd(void *vrqstp);
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/*
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* nfsd_mutex protects nn->nfsd_serv -- both the pointer itself and the members
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* of the svc_serv struct. In particular, ->sv_nrthreads but also to some
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* extent ->sv_temp_socks and ->sv_permsocks. It also protects nfsdstats.th_cnt
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*
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* If (out side the lock) nn->nfsd_serv is non-NULL, then it must point to a
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* properly initialised 'struct svc_serv' with ->sv_nrthreads > 0. That number
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* of nfsd threads must exist and each must listed in ->sp_all_threads in each
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* entry of ->sv_pools[].
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*
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* Transitions of the thread count between zero and non-zero are of particular
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* interest since the svc_serv needs to be created and initialized at that
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* point, or freed.
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*
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* Finally, the nfsd_mutex also protects some of the global variables that are
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* accessed when nfsd starts and that are settable via the write_* routines in
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* nfsctl.c. In particular:
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*
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* user_recovery_dirname
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* user_lease_time
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* nfsd_versions
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*/
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DEFINE_MUTEX(nfsd_mutex);
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/*
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* nfsd_drc_lock protects nfsd_drc_max_pages and nfsd_drc_pages_used.
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* nfsd_drc_max_pages limits the total amount of memory available for
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* version 4.1 DRC caches.
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* nfsd_drc_pages_used tracks the current version 4.1 DRC memory usage.
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*/
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spinlock_t nfsd_drc_lock;
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unsigned long nfsd_drc_max_mem;
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unsigned long nfsd_drc_mem_used;
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#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
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static struct svc_stat nfsd_acl_svcstats;
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static const struct svc_version *nfsd_acl_version[] = {
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[2] = &nfsd_acl_version2,
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[3] = &nfsd_acl_version3,
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};
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#define NFSD_ACL_MINVERS 2
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#define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version)
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static const struct svc_version *nfsd_acl_versions[NFSD_ACL_NRVERS];
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static struct svc_program nfsd_acl_program = {
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.pg_prog = NFS_ACL_PROGRAM,
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.pg_nvers = NFSD_ACL_NRVERS,
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.pg_vers = nfsd_acl_versions,
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.pg_name = "nfsacl",
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.pg_class = "nfsd",
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.pg_stats = &nfsd_acl_svcstats,
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.pg_authenticate = &svc_set_client,
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};
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static struct svc_stat nfsd_acl_svcstats = {
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.program = &nfsd_acl_program,
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};
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#endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */
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static const struct svc_version *nfsd_version[] = {
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[2] = &nfsd_version2,
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#if defined(CONFIG_NFSD_V3)
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[3] = &nfsd_version3,
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#endif
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#if defined(CONFIG_NFSD_V4)
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[4] = &nfsd_version4,
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#endif
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};
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#define NFSD_MINVERS 2
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#define NFSD_NRVERS ARRAY_SIZE(nfsd_version)
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static const struct svc_version *nfsd_versions[NFSD_NRVERS];
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struct svc_program nfsd_program = {
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#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
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.pg_next = &nfsd_acl_program,
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#endif
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.pg_prog = NFS_PROGRAM, /* program number */
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.pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */
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.pg_vers = nfsd_versions, /* version table */
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.pg_name = "nfsd", /* program name */
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.pg_class = "nfsd", /* authentication class */
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.pg_stats = &nfsd_svcstats, /* version table */
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.pg_authenticate = &svc_set_client, /* export authentication */
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};
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static bool nfsd_supported_minorversions[NFSD_SUPPORTED_MINOR_VERSION + 1] = {
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[0] = 1,
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[1] = 1,
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[2] = 1,
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};
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int nfsd_vers(int vers, enum vers_op change)
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{
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if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS)
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return 0;
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switch(change) {
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case NFSD_SET:
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nfsd_versions[vers] = nfsd_version[vers];
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#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
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if (vers < NFSD_ACL_NRVERS)
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nfsd_acl_versions[vers] = nfsd_acl_version[vers];
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#endif
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break;
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case NFSD_CLEAR:
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nfsd_versions[vers] = NULL;
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#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
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if (vers < NFSD_ACL_NRVERS)
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nfsd_acl_versions[vers] = NULL;
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#endif
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break;
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case NFSD_TEST:
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return nfsd_versions[vers] != NULL;
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case NFSD_AVAIL:
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return nfsd_version[vers] != NULL;
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}
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return 0;
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}
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static void
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nfsd_adjust_nfsd_versions4(void)
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{
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unsigned i;
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for (i = 0; i <= NFSD_SUPPORTED_MINOR_VERSION; i++) {
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if (nfsd_supported_minorversions[i])
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return;
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}
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nfsd_vers(4, NFSD_CLEAR);
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}
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int nfsd_minorversion(u32 minorversion, enum vers_op change)
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{
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if (minorversion > NFSD_SUPPORTED_MINOR_VERSION &&
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change != NFSD_AVAIL)
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return -1;
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switch(change) {
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case NFSD_SET:
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nfsd_supported_minorversions[minorversion] = true;
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nfsd_vers(4, NFSD_SET);
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break;
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case NFSD_CLEAR:
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nfsd_supported_minorversions[minorversion] = false;
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nfsd_adjust_nfsd_versions4();
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break;
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case NFSD_TEST:
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return nfsd_supported_minorversions[minorversion];
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case NFSD_AVAIL:
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return minorversion <= NFSD_SUPPORTED_MINOR_VERSION;
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}
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return 0;
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}
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/*
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* Maximum number of nfsd processes
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*/
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#define NFSD_MAXSERVS 8192
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int nfsd_nrthreads(struct net *net)
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{
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int rv = 0;
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struct nfsd_net *nn = net_generic(net, nfsd_net_id);
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mutex_lock(&nfsd_mutex);
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if (nn->nfsd_serv)
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rv = nn->nfsd_serv->sv_nrthreads;
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mutex_unlock(&nfsd_mutex);
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return rv;
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}
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static int nfsd_init_socks(struct net *net)
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{
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int error;
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struct nfsd_net *nn = net_generic(net, nfsd_net_id);
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if (!list_empty(&nn->nfsd_serv->sv_permsocks))
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return 0;
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error = svc_create_xprt(nn->nfsd_serv, "udp", net, PF_INET, NFS_PORT,
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SVC_SOCK_DEFAULTS);
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if (error < 0)
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return error;
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error = svc_create_xprt(nn->nfsd_serv, "tcp", net, PF_INET, NFS_PORT,
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SVC_SOCK_DEFAULTS);
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if (error < 0)
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return error;
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return 0;
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}
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static int nfsd_users = 0;
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static int nfsd_startup_generic(int nrservs)
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{
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int ret;
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if (nfsd_users++)
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return 0;
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/*
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* Readahead param cache - will no-op if it already exists.
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* (Note therefore results will be suboptimal if number of
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* threads is modified after nfsd start.)
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*/
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ret = nfsd_racache_init(2*nrservs);
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if (ret)
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goto dec_users;
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ret = nfs4_state_start();
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if (ret)
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goto out_racache;
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return 0;
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out_racache:
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nfsd_racache_shutdown();
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dec_users:
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nfsd_users--;
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return ret;
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}
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static void nfsd_shutdown_generic(void)
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{
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if (--nfsd_users)
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return;
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nfs4_state_shutdown();
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nfsd_racache_shutdown();
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}
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static bool nfsd_needs_lockd(void)
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{
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#if defined(CONFIG_NFSD_V3)
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return (nfsd_versions[2] != NULL) || (nfsd_versions[3] != NULL);
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#else
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return (nfsd_versions[2] != NULL);
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#endif
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}
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static int nfsd_startup_net(int nrservs, struct net *net)
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{
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struct nfsd_net *nn = net_generic(net, nfsd_net_id);
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int ret;
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if (nn->nfsd_net_up)
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return 0;
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ret = nfsd_startup_generic(nrservs);
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if (ret)
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return ret;
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ret = nfsd_init_socks(net);
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if (ret)
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goto out_socks;
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if (nfsd_needs_lockd() && !nn->lockd_up) {
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ret = lockd_up(net);
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if (ret)
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goto out_socks;
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nn->lockd_up = 1;
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}
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ret = nfs4_state_start_net(net);
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if (ret)
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goto out_lockd;
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nn->nfsd_net_up = true;
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return 0;
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out_lockd:
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if (nn->lockd_up) {
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lockd_down(net);
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nn->lockd_up = 0;
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}
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out_socks:
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nfsd_shutdown_generic();
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return ret;
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}
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static void nfsd_shutdown_net(struct net *net)
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{
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struct nfsd_net *nn = net_generic(net, nfsd_net_id);
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nfs4_state_shutdown_net(net);
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if (nn->lockd_up) {
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lockd_down(net);
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nn->lockd_up = 0;
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}
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nn->nfsd_net_up = false;
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nfsd_shutdown_generic();
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}
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static int nfsd_inetaddr_event(struct notifier_block *this, unsigned long event,
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void *ptr)
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{
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struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
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struct net_device *dev = ifa->ifa_dev->dev;
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struct net *net = dev_net(dev);
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struct nfsd_net *nn = net_generic(net, nfsd_net_id);
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struct sockaddr_in sin;
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if (event != NETDEV_DOWN)
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goto out;
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if (nn->nfsd_serv) {
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dprintk("nfsd_inetaddr_event: removed %pI4\n", &ifa->ifa_local);
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sin.sin_family = AF_INET;
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sin.sin_addr.s_addr = ifa->ifa_local;
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svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin);
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}
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out:
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return NOTIFY_DONE;
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}
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static struct notifier_block nfsd_inetaddr_notifier = {
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.notifier_call = nfsd_inetaddr_event,
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};
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#if IS_ENABLED(CONFIG_IPV6)
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static int nfsd_inet6addr_event(struct notifier_block *this,
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unsigned long event, void *ptr)
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{
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struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
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struct net_device *dev = ifa->idev->dev;
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struct net *net = dev_net(dev);
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struct nfsd_net *nn = net_generic(net, nfsd_net_id);
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struct sockaddr_in6 sin6;
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if (event != NETDEV_DOWN)
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goto out;
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if (nn->nfsd_serv) {
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dprintk("nfsd_inet6addr_event: removed %pI6\n", &ifa->addr);
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sin6.sin6_family = AF_INET6;
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sin6.sin6_addr = ifa->addr;
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if (ipv6_addr_type(&sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
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sin6.sin6_scope_id = ifa->idev->dev->ifindex;
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svc_age_temp_xprts_now(nn->nfsd_serv, (struct sockaddr *)&sin6);
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}
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out:
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return NOTIFY_DONE;
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}
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static struct notifier_block nfsd_inet6addr_notifier = {
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.notifier_call = nfsd_inet6addr_event,
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};
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#endif
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/* Only used under nfsd_mutex, so this atomic may be overkill: */
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static atomic_t nfsd_notifier_refcount = ATOMIC_INIT(0);
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static void nfsd_last_thread(struct svc_serv *serv, struct net *net)
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{
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struct nfsd_net *nn = net_generic(net, nfsd_net_id);
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/* check if the notifier still has clients */
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if (atomic_dec_return(&nfsd_notifier_refcount) == 0) {
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unregister_inetaddr_notifier(&nfsd_inetaddr_notifier);
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#if IS_ENABLED(CONFIG_IPV6)
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unregister_inet6addr_notifier(&nfsd_inet6addr_notifier);
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#endif
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}
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/*
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* write_ports can create the server without actually starting
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* any threads--if we get shut down before any threads are
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* started, then nfsd_last_thread will be run before any of this
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* other initialization has been done except the rpcb information.
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*/
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svc_rpcb_cleanup(serv, net);
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if (!nn->nfsd_net_up)
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return;
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nfsd_shutdown_net(net);
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printk(KERN_WARNING "nfsd: last server has exited, flushing export "
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"cache\n");
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nfsd_export_flush(net);
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}
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void nfsd_reset_versions(void)
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{
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int i;
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for (i = 0; i < NFSD_NRVERS; i++)
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if (nfsd_vers(i, NFSD_TEST))
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return;
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for (i = 0; i < NFSD_NRVERS; i++)
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if (i != 4)
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nfsd_vers(i, NFSD_SET);
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else {
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int minor = 0;
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while (nfsd_minorversion(minor, NFSD_SET) >= 0)
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minor++;
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}
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}
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/*
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* Each session guarantees a negotiated per slot memory cache for replies
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* which in turn consumes memory beyond the v2/v3/v4.0 server. A dedicated
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* NFSv4.1 server might want to use more memory for a DRC than a machine
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* with mutiple services.
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*
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* Impose a hard limit on the number of pages for the DRC which varies
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* according to the machines free pages. This is of course only a default.
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*
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* For now this is a #defined shift which could be under admin control
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* in the future.
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*/
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static void set_max_drc(void)
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{
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#define NFSD_DRC_SIZE_SHIFT 10
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nfsd_drc_max_mem = (nr_free_buffer_pages()
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>> NFSD_DRC_SIZE_SHIFT) * PAGE_SIZE;
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nfsd_drc_mem_used = 0;
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spin_lock_init(&nfsd_drc_lock);
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dprintk("%s nfsd_drc_max_mem %lu \n", __func__, nfsd_drc_max_mem);
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}
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static int nfsd_get_default_max_blksize(void)
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{
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struct sysinfo i;
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unsigned long long target;
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unsigned long ret;
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si_meminfo(&i);
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target = (i.totalram - i.totalhigh) << PAGE_SHIFT;
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/*
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* Aim for 1/4096 of memory per thread This gives 1MB on 4Gig
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* machines, but only uses 32K on 128M machines. Bottom out at
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* 8K on 32M and smaller. Of course, this is only a default.
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*/
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target >>= 12;
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ret = NFSSVC_MAXBLKSIZE;
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while (ret > target && ret >= 8*1024*2)
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ret /= 2;
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return ret;
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}
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static const struct svc_serv_ops nfsd_thread_sv_ops = {
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.svo_shutdown = nfsd_last_thread,
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.svo_function = nfsd,
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.svo_enqueue_xprt = svc_xprt_do_enqueue,
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.svo_setup = svc_set_num_threads,
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.svo_module = THIS_MODULE,
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};
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int nfsd_create_serv(struct net *net)
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{
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int error;
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struct nfsd_net *nn = net_generic(net, nfsd_net_id);
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WARN_ON(!mutex_is_locked(&nfsd_mutex));
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if (nn->nfsd_serv) {
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svc_get(nn->nfsd_serv);
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return 0;
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}
|
|
if (nfsd_max_blksize == 0)
|
|
nfsd_max_blksize = nfsd_get_default_max_blksize();
|
|
nfsd_reset_versions();
|
|
nn->nfsd_serv = svc_create_pooled(&nfsd_program, nfsd_max_blksize,
|
|
&nfsd_thread_sv_ops);
|
|
if (nn->nfsd_serv == NULL)
|
|
return -ENOMEM;
|
|
|
|
nn->nfsd_serv->sv_maxconn = nn->max_connections;
|
|
error = svc_bind(nn->nfsd_serv, net);
|
|
if (error < 0) {
|
|
svc_destroy(nn->nfsd_serv);
|
|
return error;
|
|
}
|
|
|
|
set_max_drc();
|
|
/* check if the notifier is already set */
|
|
if (atomic_inc_return(&nfsd_notifier_refcount) == 1) {
|
|
register_inetaddr_notifier(&nfsd_inetaddr_notifier);
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
register_inet6addr_notifier(&nfsd_inet6addr_notifier);
|
|
#endif
|
|
}
|
|
do_gettimeofday(&nn->nfssvc_boot); /* record boot time */
|
|
return 0;
|
|
}
|
|
|
|
int nfsd_nrpools(struct net *net)
|
|
{
|
|
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
|
|
|
|
if (nn->nfsd_serv == NULL)
|
|
return 0;
|
|
else
|
|
return nn->nfsd_serv->sv_nrpools;
|
|
}
|
|
|
|
int nfsd_get_nrthreads(int n, int *nthreads, struct net *net)
|
|
{
|
|
int i = 0;
|
|
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
|
|
|
|
if (nn->nfsd_serv != NULL) {
|
|
for (i = 0; i < nn->nfsd_serv->sv_nrpools && i < n; i++)
|
|
nthreads[i] = nn->nfsd_serv->sv_pools[i].sp_nrthreads;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
void nfsd_destroy(struct net *net)
|
|
{
|
|
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
|
|
int destroy = (nn->nfsd_serv->sv_nrthreads == 1);
|
|
|
|
if (destroy)
|
|
svc_shutdown_net(nn->nfsd_serv, net);
|
|
svc_destroy(nn->nfsd_serv);
|
|
if (destroy)
|
|
nn->nfsd_serv = NULL;
|
|
}
|
|
|
|
int nfsd_set_nrthreads(int n, int *nthreads, struct net *net)
|
|
{
|
|
int i = 0;
|
|
int tot = 0;
|
|
int err = 0;
|
|
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
|
|
|
|
WARN_ON(!mutex_is_locked(&nfsd_mutex));
|
|
|
|
if (nn->nfsd_serv == NULL || n <= 0)
|
|
return 0;
|
|
|
|
if (n > nn->nfsd_serv->sv_nrpools)
|
|
n = nn->nfsd_serv->sv_nrpools;
|
|
|
|
/* enforce a global maximum number of threads */
|
|
tot = 0;
|
|
for (i = 0; i < n; i++) {
|
|
nthreads[i] = min(nthreads[i], NFSD_MAXSERVS);
|
|
tot += nthreads[i];
|
|
}
|
|
if (tot > NFSD_MAXSERVS) {
|
|
/* total too large: scale down requested numbers */
|
|
for (i = 0; i < n && tot > 0; i++) {
|
|
int new = nthreads[i] * NFSD_MAXSERVS / tot;
|
|
tot -= (nthreads[i] - new);
|
|
nthreads[i] = new;
|
|
}
|
|
for (i = 0; i < n && tot > 0; i++) {
|
|
nthreads[i]--;
|
|
tot--;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* There must always be a thread in pool 0; the admin
|
|
* can't shut down NFS completely using pool_threads.
|
|
*/
|
|
if (nthreads[0] == 0)
|
|
nthreads[0] = 1;
|
|
|
|
/* apply the new numbers */
|
|
svc_get(nn->nfsd_serv);
|
|
for (i = 0; i < n; i++) {
|
|
err = nn->nfsd_serv->sv_ops->svo_setup(nn->nfsd_serv,
|
|
&nn->nfsd_serv->sv_pools[i], nthreads[i]);
|
|
if (err)
|
|
break;
|
|
}
|
|
nfsd_destroy(net);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* Adjust the number of threads and return the new number of threads.
|
|
* This is also the function that starts the server if necessary, if
|
|
* this is the first time nrservs is nonzero.
|
|
*/
|
|
int
|
|
nfsd_svc(int nrservs, struct net *net)
|
|
{
|
|
int error;
|
|
bool nfsd_up_before;
|
|
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
|
|
|
|
mutex_lock(&nfsd_mutex);
|
|
dprintk("nfsd: creating service\n");
|
|
|
|
nrservs = max(nrservs, 0);
|
|
nrservs = min(nrservs, NFSD_MAXSERVS);
|
|
error = 0;
|
|
|
|
if (nrservs == 0 && nn->nfsd_serv == NULL)
|
|
goto out;
|
|
|
|
error = nfsd_create_serv(net);
|
|
if (error)
|
|
goto out;
|
|
|
|
nfsd_up_before = nn->nfsd_net_up;
|
|
|
|
error = nfsd_startup_net(nrservs, net);
|
|
if (error)
|
|
goto out_destroy;
|
|
error = nn->nfsd_serv->sv_ops->svo_setup(nn->nfsd_serv,
|
|
NULL, nrservs);
|
|
if (error)
|
|
goto out_shutdown;
|
|
/* We are holding a reference to nn->nfsd_serv which
|
|
* we don't want to count in the return value,
|
|
* so subtract 1
|
|
*/
|
|
error = nn->nfsd_serv->sv_nrthreads - 1;
|
|
out_shutdown:
|
|
if (error < 0 && !nfsd_up_before)
|
|
nfsd_shutdown_net(net);
|
|
out_destroy:
|
|
nfsd_destroy(net); /* Release server */
|
|
out:
|
|
mutex_unlock(&nfsd_mutex);
|
|
return error;
|
|
}
|
|
|
|
|
|
/*
|
|
* This is the NFS server kernel thread
|
|
*/
|
|
static int
|
|
nfsd(void *vrqstp)
|
|
{
|
|
struct svc_rqst *rqstp = (struct svc_rqst *) vrqstp;
|
|
struct svc_xprt *perm_sock = list_entry(rqstp->rq_server->sv_permsocks.next, typeof(struct svc_xprt), xpt_list);
|
|
struct net *net = perm_sock->xpt_net;
|
|
struct nfsd_net *nn = net_generic(net, nfsd_net_id);
|
|
int err;
|
|
|
|
/* Lock module and set up kernel thread */
|
|
mutex_lock(&nfsd_mutex);
|
|
|
|
/* At this point, the thread shares current->fs
|
|
* with the init process. We need to create files with the
|
|
* umask as defined by the client instead of init's umask. */
|
|
if (unshare_fs_struct() < 0) {
|
|
printk("Unable to start nfsd thread: out of memory\n");
|
|
goto out;
|
|
}
|
|
|
|
current->fs->umask = 0;
|
|
|
|
/*
|
|
* thread is spawned with all signals set to SIG_IGN, re-enable
|
|
* the ones that will bring down the thread
|
|
*/
|
|
allow_signal(SIGKILL);
|
|
allow_signal(SIGHUP);
|
|
allow_signal(SIGINT);
|
|
allow_signal(SIGQUIT);
|
|
|
|
nfsdstats.th_cnt++;
|
|
mutex_unlock(&nfsd_mutex);
|
|
|
|
set_freezable();
|
|
|
|
/*
|
|
* The main request loop
|
|
*/
|
|
for (;;) {
|
|
/* Update sv_maxconn if it has changed */
|
|
rqstp->rq_server->sv_maxconn = nn->max_connections;
|
|
|
|
/*
|
|
* Find a socket with data available and call its
|
|
* recvfrom routine.
|
|
*/
|
|
while ((err = svc_recv(rqstp, 60*60*HZ)) == -EAGAIN)
|
|
;
|
|
if (err == -EINTR)
|
|
break;
|
|
validate_process_creds();
|
|
svc_process(rqstp);
|
|
validate_process_creds();
|
|
}
|
|
|
|
/* Clear signals before calling svc_exit_thread() */
|
|
flush_signals(current);
|
|
|
|
mutex_lock(&nfsd_mutex);
|
|
nfsdstats.th_cnt --;
|
|
|
|
out:
|
|
rqstp->rq_server = NULL;
|
|
|
|
/* Release the thread */
|
|
svc_exit_thread(rqstp);
|
|
|
|
nfsd_destroy(net);
|
|
|
|
/* Release module */
|
|
mutex_unlock(&nfsd_mutex);
|
|
module_put_and_exit(0);
|
|
return 0;
|
|
}
|
|
|
|
static __be32 map_new_errors(u32 vers, __be32 nfserr)
|
|
{
|
|
if (nfserr == nfserr_jukebox && vers == 2)
|
|
return nfserr_dropit;
|
|
if (nfserr == nfserr_wrongsec && vers < 4)
|
|
return nfserr_acces;
|
|
return nfserr;
|
|
}
|
|
|
|
/*
|
|
* A write procedure can have a large argument, and a read procedure can
|
|
* have a large reply, but no NFSv2 or NFSv3 procedure has argument and
|
|
* reply that can both be larger than a page. The xdr code has taken
|
|
* advantage of this assumption to be a sloppy about bounds checking in
|
|
* some cases. Pending a rewrite of the NFSv2/v3 xdr code to fix that
|
|
* problem, we enforce these assumptions here:
|
|
*/
|
|
static bool nfs_request_too_big(struct svc_rqst *rqstp,
|
|
const struct svc_procedure *proc)
|
|
{
|
|
/*
|
|
* The ACL code has more careful bounds-checking and is not
|
|
* susceptible to this problem:
|
|
*/
|
|
if (rqstp->rq_prog != NFS_PROGRAM)
|
|
return false;
|
|
/*
|
|
* Ditto NFSv4 (which can in theory have argument and reply both
|
|
* more than a page):
|
|
*/
|
|
if (rqstp->rq_vers >= 4)
|
|
return false;
|
|
/* The reply will be small, we're OK: */
|
|
if (proc->pc_xdrressize > 0 &&
|
|
proc->pc_xdrressize < XDR_QUADLEN(PAGE_SIZE))
|
|
return false;
|
|
|
|
return rqstp->rq_arg.len > PAGE_SIZE;
|
|
}
|
|
|
|
int
|
|
nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp)
|
|
{
|
|
const struct svc_procedure *proc;
|
|
__be32 nfserr;
|
|
__be32 *nfserrp;
|
|
|
|
dprintk("nfsd_dispatch: vers %d proc %d\n",
|
|
rqstp->rq_vers, rqstp->rq_proc);
|
|
proc = rqstp->rq_procinfo;
|
|
|
|
if (nfs_request_too_big(rqstp, proc)) {
|
|
dprintk("nfsd: NFSv%d argument too large\n", rqstp->rq_vers);
|
|
*statp = rpc_garbage_args;
|
|
return 1;
|
|
}
|
|
/*
|
|
* Give the xdr decoder a chance to change this if it wants
|
|
* (necessary in the NFSv4.0 compound case)
|
|
*/
|
|
rqstp->rq_cachetype = proc->pc_cachetype;
|
|
/* Decode arguments */
|
|
if (proc->pc_decode &&
|
|
!proc->pc_decode(rqstp, (__be32*)rqstp->rq_arg.head[0].iov_base)) {
|
|
dprintk("nfsd: failed to decode arguments!\n");
|
|
*statp = rpc_garbage_args;
|
|
return 1;
|
|
}
|
|
|
|
/* Check whether we have this call in the cache. */
|
|
switch (nfsd_cache_lookup(rqstp)) {
|
|
case RC_DROPIT:
|
|
return 0;
|
|
case RC_REPLY:
|
|
return 1;
|
|
case RC_DOIT:;
|
|
/* do it */
|
|
}
|
|
|
|
/* need to grab the location to store the status, as
|
|
* nfsv4 does some encoding while processing
|
|
*/
|
|
nfserrp = rqstp->rq_res.head[0].iov_base
|
|
+ rqstp->rq_res.head[0].iov_len;
|
|
rqstp->rq_res.head[0].iov_len += sizeof(__be32);
|
|
|
|
/* Now call the procedure handler, and encode NFS status. */
|
|
nfserr = proc->pc_func(rqstp);
|
|
nfserr = map_new_errors(rqstp->rq_vers, nfserr);
|
|
if (nfserr == nfserr_dropit || test_bit(RQ_DROPME, &rqstp->rq_flags)) {
|
|
dprintk("nfsd: Dropping request; may be revisited later\n");
|
|
nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
|
|
return 0;
|
|
}
|
|
|
|
if (rqstp->rq_proc != 0)
|
|
*nfserrp++ = nfserr;
|
|
|
|
/* Encode result.
|
|
* For NFSv2, additional info is never returned in case of an error.
|
|
*/
|
|
if (!(nfserr && rqstp->rq_vers == 2)) {
|
|
if (proc->pc_encode && !proc->pc_encode(rqstp, nfserrp)) {
|
|
/* Failed to encode result. Release cache entry */
|
|
dprintk("nfsd: failed to encode result!\n");
|
|
nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
|
|
*statp = rpc_system_err;
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
/* Store reply in cache. */
|
|
nfsd_cache_update(rqstp, rqstp->rq_cachetype, statp + 1);
|
|
return 1;
|
|
}
|
|
|
|
int nfsd_pool_stats_open(struct inode *inode, struct file *file)
|
|
{
|
|
int ret;
|
|
struct nfsd_net *nn = net_generic(inode->i_sb->s_fs_info, nfsd_net_id);
|
|
|
|
mutex_lock(&nfsd_mutex);
|
|
if (nn->nfsd_serv == NULL) {
|
|
mutex_unlock(&nfsd_mutex);
|
|
return -ENODEV;
|
|
}
|
|
/* bump up the psudo refcount while traversing */
|
|
svc_get(nn->nfsd_serv);
|
|
ret = svc_pool_stats_open(nn->nfsd_serv, file);
|
|
mutex_unlock(&nfsd_mutex);
|
|
return ret;
|
|
}
|
|
|
|
int nfsd_pool_stats_release(struct inode *inode, struct file *file)
|
|
{
|
|
int ret = seq_release(inode, file);
|
|
struct net *net = inode->i_sb->s_fs_info;
|
|
|
|
mutex_lock(&nfsd_mutex);
|
|
/* this function really, really should have been called svc_put() */
|
|
nfsd_destroy(net);
|
|
mutex_unlock(&nfsd_mutex);
|
|
return ret;
|
|
}
|