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-rw-r--r--fs/nfsd/nfssvc.c385
1 files changed, 385 insertions, 0 deletions
diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
new file mode 100644
index 000000000000..39551657e656
--- /dev/null
+++ b/fs/nfsd/nfssvc.c
@@ -0,0 +1,385 @@
+/*
+ * linux/fs/nfsd/nfssvc.c
+ *
+ * Central processing for nfsd.
+ *
+ * Authors: Olaf Kirch (okir@monad.swb.de)
+ *
+ * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+
+#include <linux/time.h>
+#include <linux/errno.h>
+#include <linux/nfs.h>
+#include <linux/in.h>
+#include <linux/uio.h>
+#include <linux/unistd.h>
+#include <linux/slab.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/fs_struct.h>
+
+#include <linux/sunrpc/types.h>
+#include <linux/sunrpc/stats.h>
+#include <linux/sunrpc/svc.h>
+#include <linux/sunrpc/svcsock.h>
+#include <linux/sunrpc/cache.h>
+#include <linux/nfsd/nfsd.h>
+#include <linux/nfsd/stats.h>
+#include <linux/nfsd/cache.h>
+#include <linux/lockd/bind.h>
+
+#define NFSDDBG_FACILITY NFSDDBG_SVC
+
+/* these signals will be delivered to an nfsd thread
+ * when handling a request
+ */
+#define ALLOWED_SIGS (sigmask(SIGKILL))
+/* these signals will be delivered to an nfsd thread
+ * when not handling a request. i.e. when waiting
+ */
+#define SHUTDOWN_SIGS (sigmask(SIGKILL) | sigmask(SIGHUP) | sigmask(SIGINT) | sigmask(SIGQUIT))
+/* if the last thread dies with SIGHUP, then the exports table is
+ * left unchanged ( like 2.4-{0-9} ). Any other signal will clear
+ * the exports table (like 2.2).
+ */
+#define SIG_NOCLEAN SIGHUP
+
+extern struct svc_program nfsd_program;
+static void nfsd(struct svc_rqst *rqstp);
+struct timeval nfssvc_boot;
+static struct svc_serv *nfsd_serv;
+static atomic_t nfsd_busy;
+static unsigned long nfsd_last_call;
+static DEFINE_SPINLOCK(nfsd_call_lock);
+
+struct nfsd_list {
+ struct list_head list;
+ struct task_struct *task;
+};
+static struct list_head nfsd_list = LIST_HEAD_INIT(nfsd_list);
+
+/*
+ * Maximum number of nfsd processes
+ */
+#define NFSD_MAXSERVS 8192
+
+int nfsd_nrthreads(void)
+{
+ if (nfsd_serv == NULL)
+ return 0;
+ else
+ return nfsd_serv->sv_nrthreads;
+}
+
+int
+nfsd_svc(unsigned short port, int nrservs)
+{
+ int error;
+ int none_left;
+ struct list_head *victim;
+
+ lock_kernel();
+ dprintk("nfsd: creating service\n");
+ error = -EINVAL;
+ if (nrservs <= 0)
+ nrservs = 0;
+ if (nrservs > NFSD_MAXSERVS)
+ nrservs = NFSD_MAXSERVS;
+
+ /* Readahead param cache - will no-op if it already exists */
+ error = nfsd_racache_init(2*nrservs);
+ if (error<0)
+ goto out;
+ error = nfs4_state_init();
+ if (error<0)
+ goto out;
+ if (!nfsd_serv) {
+ atomic_set(&nfsd_busy, 0);
+ error = -ENOMEM;
+ nfsd_serv = svc_create(&nfsd_program, NFSD_BUFSIZE);
+ if (nfsd_serv == NULL)
+ goto out;
+ error = svc_makesock(nfsd_serv, IPPROTO_UDP, port);
+ if (error < 0)
+ goto failure;
+
+#ifdef CONFIG_NFSD_TCP
+ error = svc_makesock(nfsd_serv, IPPROTO_TCP, port);
+ if (error < 0)
+ goto failure;
+#endif
+ do_gettimeofday(&nfssvc_boot); /* record boot time */
+ } else
+ nfsd_serv->sv_nrthreads++;
+ nrservs -= (nfsd_serv->sv_nrthreads-1);
+ while (nrservs > 0) {
+ nrservs--;
+ __module_get(THIS_MODULE);
+ error = svc_create_thread(nfsd, nfsd_serv);
+ if (error < 0) {
+ module_put(THIS_MODULE);
+ break;
+ }
+ }
+ victim = nfsd_list.next;
+ while (nrservs < 0 && victim != &nfsd_list) {
+ struct nfsd_list *nl =
+ list_entry(victim,struct nfsd_list, list);
+ victim = victim->next;
+ send_sig(SIG_NOCLEAN, nl->task, 1);
+ nrservs++;
+ }
+ failure:
+ none_left = (nfsd_serv->sv_nrthreads == 1);
+ svc_destroy(nfsd_serv); /* Release server */
+ if (none_left) {
+ nfsd_serv = NULL;
+ nfsd_racache_shutdown();
+ nfs4_state_shutdown();
+ }
+ out:
+ unlock_kernel();
+ return error;
+}
+
+static inline void
+update_thread_usage(int busy_threads)
+{
+ unsigned long prev_call;
+ unsigned long diff;
+ int decile;
+
+ spin_lock(&nfsd_call_lock);
+ prev_call = nfsd_last_call;
+ nfsd_last_call = jiffies;
+ decile = busy_threads*10/nfsdstats.th_cnt;
+ if (decile>0 && decile <= 10) {
+ diff = nfsd_last_call - prev_call;
+ if ( (nfsdstats.th_usage[decile-1] += diff) >= NFSD_USAGE_WRAP)
+ nfsdstats.th_usage[decile-1] -= NFSD_USAGE_WRAP;
+ if (decile == 10)
+ nfsdstats.th_fullcnt++;
+ }
+ spin_unlock(&nfsd_call_lock);
+}
+
+/*
+ * This is the NFS server kernel thread
+ */
+static void
+nfsd(struct svc_rqst *rqstp)
+{
+ struct svc_serv *serv = rqstp->rq_server;
+ struct fs_struct *fsp;
+ int err;
+ struct nfsd_list me;
+ sigset_t shutdown_mask, allowed_mask;
+
+ /* Lock module and set up kernel thread */
+ lock_kernel();
+ daemonize("nfsd");
+
+ /* After daemonize() this kernel thread shares current->fs
+ * with the init process. We need to create files with a
+ * umask of 0 instead of init's umask. */
+ fsp = copy_fs_struct(current->fs);
+ if (!fsp) {
+ printk("Unable to start nfsd thread: out of memory\n");
+ goto out;
+ }
+ exit_fs(current);
+ current->fs = fsp;
+ current->fs->umask = 0;
+
+ siginitsetinv(&shutdown_mask, SHUTDOWN_SIGS);
+ siginitsetinv(&allowed_mask, ALLOWED_SIGS);
+
+ nfsdstats.th_cnt++;
+
+ lockd_up(); /* start lockd */
+
+ me.task = current;
+ list_add(&me.list, &nfsd_list);
+
+ unlock_kernel();
+
+ /*
+ * We want less throttling in balance_dirty_pages() so that nfs to
+ * localhost doesn't cause nfsd to lock up due to all the client's
+ * dirty pages.
+ */
+ current->flags |= PF_LESS_THROTTLE;
+
+ /*
+ * The main request loop
+ */
+ for (;;) {
+ /* Block all but the shutdown signals */
+ sigprocmask(SIG_SETMASK, &shutdown_mask, NULL);
+
+ /*
+ * Find a socket with data available and call its
+ * recvfrom routine.
+ */
+ while ((err = svc_recv(serv, rqstp,
+ 60*60*HZ)) == -EAGAIN)
+ ;
+ if (err < 0)
+ break;
+ update_thread_usage(atomic_read(&nfsd_busy));
+ atomic_inc(&nfsd_busy);
+
+ /* Lock the export hash tables for reading. */
+ exp_readlock();
+
+ /* Process request with signals blocked. */
+ sigprocmask(SIG_SETMASK, &allowed_mask, NULL);
+
+ svc_process(serv, rqstp);
+
+ /* Unlock export hash tables */
+ exp_readunlock();
+ update_thread_usage(atomic_read(&nfsd_busy));
+ atomic_dec(&nfsd_busy);
+ }
+
+ if (err != -EINTR) {
+ printk(KERN_WARNING "nfsd: terminating on error %d\n", -err);
+ } else {
+ unsigned int signo;
+
+ for (signo = 1; signo <= _NSIG; signo++)
+ if (sigismember(&current->pending.signal, signo) &&
+ !sigismember(&current->blocked, signo))
+ break;
+ err = signo;
+ }
+
+ lock_kernel();
+
+ /* Release lockd */
+ lockd_down();
+
+ /* Check if this is last thread */
+ if (serv->sv_nrthreads==1) {
+
+ printk(KERN_WARNING "nfsd: last server has exited\n");
+ if (err != SIG_NOCLEAN) {
+ printk(KERN_WARNING "nfsd: unexporting all filesystems\n");
+ nfsd_export_flush();
+ }
+ nfsd_serv = NULL;
+ nfsd_racache_shutdown(); /* release read-ahead cache */
+ nfs4_state_shutdown();
+ }
+ list_del(&me.list);
+ nfsdstats.th_cnt --;
+
+out:
+ /* Release the thread */
+ svc_exit_thread(rqstp);
+
+ /* Release module */
+ module_put_and_exit(0);
+}
+
+int
+nfsd_dispatch(struct svc_rqst *rqstp, u32 *statp)
+{
+ struct svc_procedure *proc;
+ kxdrproc_t xdr;
+ u32 nfserr;
+ u32 *nfserrp;
+
+ dprintk("nfsd_dispatch: vers %d proc %d\n",
+ rqstp->rq_vers, rqstp->rq_proc);
+ proc = rqstp->rq_procinfo;
+
+ /* Check whether we have this call in the cache. */
+ switch (nfsd_cache_lookup(rqstp, proc->pc_cachetype)) {
+ case RC_INTR:
+ case RC_DROPIT:
+ return 0;
+ case RC_REPLY:
+ return 1;
+ case RC_DOIT:;
+ /* do it */
+ }
+
+ /* Decode arguments */
+ xdr = proc->pc_decode;
+ if (xdr && !xdr(rqstp, (u32*)rqstp->rq_arg.head[0].iov_base,
+ rqstp->rq_argp)) {
+ dprintk("nfsd: failed to decode arguments!\n");
+ nfsd_cache_update(rqstp, RC_NOCACHE, NULL);
+ *statp = rpc_garbage_args;
+ return 1;
+ }
+
+ /* 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(u32);
+
+ /* Now call the procedure handler, and encode NFS status. */
+ nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
+ if (nfserr == nfserr_jukebox && rqstp->rq_vers == 2)
+ nfserr = nfserr_dropit;
+ if (nfserr == nfserr_dropit) {
+ dprintk("nfsd: Dropping request due to malloc failure!\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, proc->pc_cachetype, statp + 1);
+ return 1;
+}
+
+extern struct svc_version nfsd_version2, nfsd_version3, nfsd_version4;
+
+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_NRVERS (sizeof(nfsd_version)/sizeof(nfsd_version[0]))
+struct svc_program nfsd_program = {
+ .pg_prog = NFS_PROGRAM, /* program number */
+ .pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */
+ .pg_vers = nfsd_version, /* 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 */
+
+};
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