diff options
author | 2015-08-04 12:17:53 -0700 | |
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committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/fs/nfsd/nfssvc.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/fs/nfsd/nfssvc.c')
-rw-r--r-- | kernel/fs/nfsd/nfssvc.c | 752 |
1 files changed, 752 insertions, 0 deletions
diff --git a/kernel/fs/nfsd/nfssvc.c b/kernel/fs/nfsd/nfssvc.c new file mode 100644 index 000000000..9277cc91c --- /dev/null +++ b/kernel/fs/nfsd/nfssvc.c @@ -0,0 +1,752 @@ +/* + * Central processing for nfsd. + * + * Authors: Olaf Kirch (okir@monad.swb.de) + * + * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de> + */ + +#include <linux/sched.h> +#include <linux/freezer.h> +#include <linux/module.h> +#include <linux/fs_struct.h> +#include <linux/swap.h> + +#include <linux/sunrpc/stats.h> +#include <linux/sunrpc/svcsock.h> +#include <linux/lockd/bind.h> +#include <linux/nfsacl.h> +#include <linux/seq_file.h> +#include <net/net_namespace.h> +#include "nfsd.h" +#include "cache.h" +#include "vfs.h" +#include "netns.h" + +#define NFSDDBG_FACILITY NFSDDBG_SVC + +extern struct svc_program nfsd_program; +static int nfsd(void *vrqstp); + +/* + * nfsd_mutex protects nn->nfsd_serv -- both the pointer itself and the members + * of the svc_serv struct. In particular, ->sv_nrthreads but also to some + * extent ->sv_temp_socks and ->sv_permsocks. It also protects nfsdstats.th_cnt + * + * If (out side the lock) nn->nfsd_serv is non-NULL, then it must point to a + * properly initialised 'struct svc_serv' with ->sv_nrthreads > 0. That number + * of nfsd threads must exist and each must listed in ->sp_all_threads in each + * entry of ->sv_pools[]. + * + * Transitions of the thread count between zero and non-zero are of particular + * interest since the svc_serv needs to be created and initialized at that + * point, or freed. + * + * Finally, the nfsd_mutex also protects some of the global variables that are + * accessed when nfsd starts and that are settable via the write_* routines in + * nfsctl.c. In particular: + * + * user_recovery_dirname + * user_lease_time + * nfsd_versions + */ +DEFINE_MUTEX(nfsd_mutex); + +/* + * nfsd_drc_lock protects nfsd_drc_max_pages and nfsd_drc_pages_used. + * nfsd_drc_max_pages limits the total amount of memory available for + * version 4.1 DRC caches. + * nfsd_drc_pages_used tracks the current version 4.1 DRC memory usage. + */ +spinlock_t nfsd_drc_lock; +unsigned long nfsd_drc_max_mem; +unsigned long nfsd_drc_mem_used; + +#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) +static struct svc_stat nfsd_acl_svcstats; +static struct svc_version * nfsd_acl_version[] = { + [2] = &nfsd_acl_version2, + [3] = &nfsd_acl_version3, +}; + +#define NFSD_ACL_MINVERS 2 +#define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version) +static struct svc_version *nfsd_acl_versions[NFSD_ACL_NRVERS]; + +static struct svc_program nfsd_acl_program = { + .pg_prog = NFS_ACL_PROGRAM, + .pg_nvers = NFSD_ACL_NRVERS, + .pg_vers = nfsd_acl_versions, + .pg_name = "nfsacl", + .pg_class = "nfsd", + .pg_stats = &nfsd_acl_svcstats, + .pg_authenticate = &svc_set_client, +}; + +static struct svc_stat nfsd_acl_svcstats = { + .program = &nfsd_acl_program, +}; +#endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */ + +static struct svc_version * nfsd_version[] = { + [2] = &nfsd_version2, +#if defined(CONFIG_NFSD_V3) + [3] = &nfsd_version3, +#endif +#if defined(CONFIG_NFSD_V4) + [4] = &nfsd_version4, +#endif +}; + +#define NFSD_MINVERS 2 +#define NFSD_NRVERS ARRAY_SIZE(nfsd_version) +static struct svc_version *nfsd_versions[NFSD_NRVERS]; + +struct svc_program nfsd_program = { +#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) + .pg_next = &nfsd_acl_program, +#endif + .pg_prog = NFS_PROGRAM, /* program number */ + .pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */ + .pg_vers = nfsd_versions, /* version table */ + .pg_name = "nfsd", /* program name */ + .pg_class = "nfsd", /* authentication class */ + .pg_stats = &nfsd_svcstats, /* version table */ + .pg_authenticate = &svc_set_client, /* export authentication */ + +}; + +static bool nfsd_supported_minorversions[NFSD_SUPPORTED_MINOR_VERSION + 1] = { + [0] = 1, + [1] = 1, + [2] = 1, +}; + +int nfsd_vers(int vers, enum vers_op change) +{ + if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS) + return 0; + switch(change) { + case NFSD_SET: + nfsd_versions[vers] = nfsd_version[vers]; +#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) + if (vers < NFSD_ACL_NRVERS) + nfsd_acl_versions[vers] = nfsd_acl_version[vers]; +#endif + break; + case NFSD_CLEAR: + nfsd_versions[vers] = NULL; +#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) + if (vers < NFSD_ACL_NRVERS) + nfsd_acl_versions[vers] = NULL; +#endif + break; + case NFSD_TEST: + return nfsd_versions[vers] != NULL; + case NFSD_AVAIL: + return nfsd_version[vers] != NULL; + } + return 0; +} + +int nfsd_minorversion(u32 minorversion, enum vers_op change) +{ + if (minorversion > NFSD_SUPPORTED_MINOR_VERSION) + return -1; + switch(change) { + case NFSD_SET: + nfsd_supported_minorversions[minorversion] = true; + break; + case NFSD_CLEAR: + nfsd_supported_minorversions[minorversion] = false; + break; + case NFSD_TEST: + return nfsd_supported_minorversions[minorversion]; + case NFSD_AVAIL: + return minorversion <= NFSD_SUPPORTED_MINOR_VERSION; + } + return 0; +} + +/* + * Maximum number of nfsd processes + */ +#define NFSD_MAXSERVS 8192 + +int nfsd_nrthreads(struct net *net) +{ + int rv = 0; + struct nfsd_net *nn = net_generic(net, nfsd_net_id); + + mutex_lock(&nfsd_mutex); + if (nn->nfsd_serv) + rv = nn->nfsd_serv->sv_nrthreads; + mutex_unlock(&nfsd_mutex); + return rv; +} + +static int nfsd_init_socks(struct net *net) +{ + int error; + struct nfsd_net *nn = net_generic(net, nfsd_net_id); + + if (!list_empty(&nn->nfsd_serv->sv_permsocks)) + return 0; + + error = svc_create_xprt(nn->nfsd_serv, "udp", net, PF_INET, NFS_PORT, + SVC_SOCK_DEFAULTS); + if (error < 0) + return error; + + error = svc_create_xprt(nn->nfsd_serv, "tcp", net, PF_INET, NFS_PORT, + SVC_SOCK_DEFAULTS); + if (error < 0) + return error; + + return 0; +} + +static int nfsd_users = 0; + +static int nfsd_startup_generic(int nrservs) +{ + int ret; + + if (nfsd_users++) + return 0; + + /* + * Readahead param cache - will no-op if it already exists. + * (Note therefore results will be suboptimal if number of + * threads is modified after nfsd start.) + */ + ret = nfsd_racache_init(2*nrservs); + if (ret) + goto dec_users; + + ret = nfs4_state_start(); + if (ret) + goto out_racache; + return 0; + +out_racache: + nfsd_racache_shutdown(); +dec_users: + nfsd_users--; + return ret; +} + +static void nfsd_shutdown_generic(void) +{ + if (--nfsd_users) + return; + + nfs4_state_shutdown(); + nfsd_racache_shutdown(); +} + +static bool nfsd_needs_lockd(void) +{ +#if defined(CONFIG_NFSD_V3) + return (nfsd_versions[2] != NULL) || (nfsd_versions[3] != NULL); +#else + return (nfsd_versions[2] != NULL); +#endif +} + +static int nfsd_startup_net(int nrservs, struct net *net) +{ + struct nfsd_net *nn = net_generic(net, nfsd_net_id); + int ret; + + if (nn->nfsd_net_up) + return 0; + + ret = nfsd_startup_generic(nrservs); + if (ret) + return ret; + ret = nfsd_init_socks(net); + if (ret) + goto out_socks; + + if (nfsd_needs_lockd() && !nn->lockd_up) { + ret = lockd_up(net); + if (ret) + goto out_socks; + nn->lockd_up = 1; + } + + ret = nfs4_state_start_net(net); + if (ret) + goto out_lockd; + + nn->nfsd_net_up = true; + return 0; + +out_lockd: + if (nn->lockd_up) { + lockd_down(net); + nn->lockd_up = 0; + } +out_socks: + nfsd_shutdown_generic(); + return ret; +} + +static void nfsd_shutdown_net(struct net *net) +{ + struct nfsd_net *nn = net_generic(net, nfsd_net_id); + + nfs4_state_shutdown_net(net); + if (nn->lockd_up) { + lockd_down(net); + nn->lockd_up = 0; + } + nn->nfsd_net_up = false; + nfsd_shutdown_generic(); +} + +static void nfsd_last_thread(struct svc_serv *serv, struct net *net) +{ + struct nfsd_net *nn = net_generic(net, nfsd_net_id); + + /* + * write_ports can create the server without actually starting + * any threads--if we get shut down before any threads are + * started, then nfsd_last_thread will be run before any of this + * other initialization has been done. + */ + if (!nn->nfsd_net_up) + return; + nfsd_shutdown_net(net); + + svc_rpcb_cleanup(serv, net); + + printk(KERN_WARNING "nfsd: last server has exited, flushing export " + "cache\n"); + nfsd_export_flush(net); +} + +void nfsd_reset_versions(void) +{ + int found_one = 0; + int i; + + for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) { + if (nfsd_program.pg_vers[i]) + found_one = 1; + } + + if (!found_one) { + for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) + nfsd_program.pg_vers[i] = nfsd_version[i]; +#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) + for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) + nfsd_acl_program.pg_vers[i] = + nfsd_acl_version[i]; +#endif + } +} + +/* + * Each session guarantees a negotiated per slot memory cache for replies + * which in turn consumes memory beyond the v2/v3/v4.0 server. A dedicated + * NFSv4.1 server might want to use more memory for a DRC than a machine + * with mutiple services. + * + * Impose a hard limit on the number of pages for the DRC which varies + * according to the machines free pages. This is of course only a default. + * + * For now this is a #defined shift which could be under admin control + * in the future. + */ +static void set_max_drc(void) +{ + #define NFSD_DRC_SIZE_SHIFT 10 + nfsd_drc_max_mem = (nr_free_buffer_pages() + >> NFSD_DRC_SIZE_SHIFT) * PAGE_SIZE; + nfsd_drc_mem_used = 0; + spin_lock_init(&nfsd_drc_lock); + dprintk("%s nfsd_drc_max_mem %lu \n", __func__, nfsd_drc_max_mem); +} + +static int nfsd_get_default_max_blksize(void) +{ + struct sysinfo i; + unsigned long long target; + unsigned long ret; + + si_meminfo(&i); + target = (i.totalram - i.totalhigh) << PAGE_SHIFT; + /* + * Aim for 1/4096 of memory per thread This gives 1MB on 4Gig + * machines, but only uses 32K on 128M machines. Bottom out at + * 8K on 32M and smaller. Of course, this is only a default. + */ + target >>= 12; + + ret = NFSSVC_MAXBLKSIZE; + while (ret > target && ret >= 8*1024*2) + ret /= 2; + return ret; +} + +int nfsd_create_serv(struct net *net) +{ + int error; + struct nfsd_net *nn = net_generic(net, nfsd_net_id); + + WARN_ON(!mutex_is_locked(&nfsd_mutex)); + if (nn->nfsd_serv) { + svc_get(nn->nfsd_serv); + return 0; + } + 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_last_thread, nfsd, THIS_MODULE); + 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(); + 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 = svc_set_num_threads(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 = svc_set_num_threads(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 a + * umask of 0 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; +} + +int +nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp) +{ + struct svc_procedure *proc; + kxdrproc_t xdr; + __be32 nfserr; + __be32 *nfserrp; + + dprintk("nfsd_dispatch: vers %d proc %d\n", + rqstp->rq_vers, rqstp->rq_proc); + proc = rqstp->rq_procinfo; + + /* + * 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 */ + xdr = proc->pc_decode; + if (xdr && !xdr(rqstp, (__be32*)rqstp->rq_arg.head[0].iov_base, + rqstp->rq_argp)) { + 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, rqstp->rq_argp, rqstp->rq_resp); + 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)) { + xdr = proc->pc_encode; + if (xdr && !xdr(rqstp, nfserrp, + rqstp->rq_resp)) { + /* 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; +} |