From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- fs/nfsd/nfssvc.c | 385 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 385 insertions(+) create mode 100644 fs/nfsd/nfssvc.c (limited to 'fs/nfsd/nfssvc.c') diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c new file mode 100644 index 00000000000..39551657e65 --- /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 + */ + +#include +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#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(¤t->pending.signal, signo) && + !sigismember(¤t->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 */ + +}; -- cgit v1.2.3