X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=blobdiff_plain;f=fs%2Fnfsd%2Fnfssvc.c;h=fcc0010882617831d487d71fb0984646adef14f7;hp=221eeaa68a2d4e196741ef1d45ace8c195656f0c;hb=29ab23cc5d351658d01a4327d55e9106a73fd04f;hpb=45457e0916f8253691a44d3574949b6d3d5872b1 diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index 221eeaa..fcc0010 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -18,9 +18,10 @@ #include #include #include -#include #include #include +#include +#include #include #include @@ -33,30 +34,48 @@ #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); +static int nfsd(void *vrqstp); struct timeval nfssvc_boot; - struct svc_serv *nfsd_serv; -static atomic_t nfsd_busy; -static unsigned long nfsd_last_call; -static DEFINE_SPINLOCK(nfsd_call_lock); + +/* + * nfsd_mutex protects 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) 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); +struct svc_serv *nfsd_serv; + +/* + * 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 int nfsd_drc_max_mem; +unsigned int nfsd_drc_mem_used; #if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) static struct svc_stat nfsd_acl_svcstats; @@ -112,6 +131,8 @@ struct svc_program nfsd_program = { }; +u32 nfsd_supported_minorversion; + int nfsd_vers(int vers, enum vers_op change) { if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS) @@ -138,6 +159,28 @@ int nfsd_vers(int vers, enum vers_op change) } 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_minorversion = minorversion; + break; + case NFSD_CLEAR: + if (minorversion == 0) + return -1; + nfsd_supported_minorversion = minorversion - 1; + break; + case NFSD_TEST: + return minorversion <= nfsd_supported_minorversion; + case NFSD_AVAIL: + return minorversion <= NFSD_SUPPORTED_MINOR_VERSION; + } + return 0; +} + /* * Maximum number of nfsd processes */ @@ -145,28 +188,27 @@ int nfsd_vers(int vers, enum vers_op change) int nfsd_nrthreads(void) { - if (nfsd_serv == NULL) - return 0; - else - return nfsd_serv->sv_nrthreads; + int rv = 0; + mutex_lock(&nfsd_mutex); + if (nfsd_serv) + rv = nfsd_serv->sv_nrthreads; + mutex_unlock(&nfsd_mutex); + return rv; } -static int killsig; /* signal that was used to kill last nfsd */ static void nfsd_last_thread(struct svc_serv *serv) { /* When last nfsd thread exits we need to do some clean-up */ - struct svc_sock *svsk; - list_for_each_entry(svsk, &serv->sv_permsocks, sk_list) + struct svc_xprt *xprt; + list_for_each_entry(xprt, &serv->sv_permsocks, xpt_list) lockd_down(); nfsd_serv = NULL; nfsd_racache_shutdown(); nfs4_state_shutdown(); - printk(KERN_WARNING "nfsd: last server has exited\n"); - if (killsig != SIG_NOCLEAN) { - printk(KERN_WARNING "nfsd: unexporting all filesystems\n"); - nfsd_export_flush(); - } + printk(KERN_WARNING "nfsd: last server has exited, flushing export " + "cache\n"); + nfsd_export_flush(); } void nfsd_reset_versions(void) @@ -190,13 +232,35 @@ void nfsd_reset_versions(void) } } +/* + * 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 %u \n", __func__, nfsd_drc_max_mem); +} + int nfsd_create_serv(void) { int err = 0; - lock_kernel(); + + WARN_ON(!mutex_is_locked(&nfsd_mutex)); if (nfsd_serv) { svc_get(nfsd_serv); - unlock_kernel(); return 0; } if (nfsd_max_blksize == 0) { @@ -216,14 +280,13 @@ int nfsd_create_serv(void) nfsd_max_blksize /= 2; } - atomic_set(&nfsd_busy, 0); - nfsd_serv = svc_create_pooled(&nfsd_program, - nfsd_max_blksize, - nfsd_last_thread, - nfsd, SIG_NOCLEAN, THIS_MODULE); + nfsd_serv = svc_create_pooled(&nfsd_program, nfsd_max_blksize, + nfsd_last_thread, nfsd, THIS_MODULE); if (nfsd_serv == NULL) err = -ENOMEM; - unlock_kernel(); + else + set_max_drc(); + do_gettimeofday(&nfssvc_boot); /* record boot time */ return err; } @@ -234,27 +297,24 @@ static int nfsd_init_socks(int port) if (!list_empty(&nfsd_serv->sv_permsocks)) return 0; - error = lockd_up(IPPROTO_UDP); - if (error >= 0) { - error = svc_makesock(nfsd_serv, IPPROTO_UDP, port, + error = svc_create_xprt(nfsd_serv, "udp", PF_INET, port, SVC_SOCK_DEFAULTS); - if (error < 0) - lockd_down(); - } if (error < 0) return error; -#ifdef CONFIG_NFSD_TCP - error = lockd_up(IPPROTO_TCP); - if (error >= 0) { - error = svc_makesock(nfsd_serv, IPPROTO_TCP, port, + error = lockd_up(); + if (error < 0) + return error; + + error = svc_create_xprt(nfsd_serv, "tcp", PF_INET, port, SVC_SOCK_DEFAULTS); - if (error < 0) - lockd_down(); - } if (error < 0) return error; -#endif + + error = lockd_up(); + if (error < 0) + return error; + return 0; } @@ -284,6 +344,8 @@ int nfsd_set_nrthreads(int n, int *nthreads) int tot = 0; int err = 0; + WARN_ON(!mutex_is_locked(&nfsd_mutex)); + if (nfsd_serv == NULL || n <= 0) return 0; @@ -318,7 +380,6 @@ int nfsd_set_nrthreads(int n, int *nthreads) nthreads[0] = 1; /* apply the new numbers */ - lock_kernel(); svc_get(nfsd_serv); for (i = 0; i < n; i++) { err = svc_set_num_threads(nfsd_serv, &nfsd_serv->sv_pools[i], @@ -327,7 +388,6 @@ int nfsd_set_nrthreads(int n, int *nthreads) break; } svc_destroy(nfsd_serv); - unlock_kernel(); return err; } @@ -336,21 +396,23 @@ int nfsd_svc(unsigned short port, int nrservs) { int error; - - lock_kernel(); + + mutex_lock(&nfsd_mutex); dprintk("nfsd: creating service\n"); - error = -EINVAL; if (nrservs <= 0) nrservs = 0; if (nrservs > NFSD_MAXSERVS) nrservs = NFSD_MAXSERVS; - + error = 0; + if (nrservs == 0 && nfsd_serv == NULL) + goto out; + /* Readahead param cache - will no-op if it already exists */ error = nfsd_racache_init(2*nrservs); if (error<0) goto out; error = nfs4_state_start(); - if (error<0) + if (error) goto out; nfsd_reset_versions(); @@ -364,68 +426,53 @@ nfsd_svc(unsigned short port, int nrservs) goto failure; error = svc_set_num_threads(nfsd_serv, NULL, nrservs); + if (error == 0) + /* We are holding a reference to nfsd_serv which + * we don't want to count in the return value, + * so subtract 1 + */ + error = nfsd_serv->sv_nrthreads - 1; failure: svc_destroy(nfsd_serv); /* Release server */ out: - unlock_kernel(); + mutex_unlock(&nfsd_mutex); 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) +static int +nfsd(void *vrqstp) { - struct fs_struct *fsp; - int err; - sigset_t shutdown_mask, allowed_mask; + struct svc_rqst *rqstp = (struct svc_rqst *) vrqstp; + int err, preverr = 0; /* Lock module and set up kernel thread */ - lock_kernel(); - daemonize("nfsd"); + mutex_lock(&nfsd_mutex); - /* After daemonize() this kernel thread shares current->fs + /* 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. */ - fsp = copy_fs_struct(current->fs); - if (!fsp) { + if (unshare_fs_struct() < 0) { 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); + /* + * 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++; - - rqstp->rq_task = current; - - unlock_kernel(); + mutex_unlock(&nfsd_mutex); /* * We want less throttling in balance_dirty_pages() so that nfs to @@ -439,50 +486,38 @@ nfsd(struct svc_rqst *rqstp) * 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(rqstp, 60*60*HZ)) == -EAGAIN) ; - if (err < 0) + if (err == -EINTR) break; - update_thread_usage(atomic_read(&nfsd_busy)); - atomic_inc(&nfsd_busy); + else if (err < 0) { + if (err != preverr) { + printk(KERN_WARNING "%s: unexpected error " + "from svc_recv (%d)\n", __func__, -err); + preverr = err; + } + schedule_timeout_uninterruptible(HZ); + continue; + } + /* Lock the export hash tables for reading. */ exp_readlock(); - /* Process request with signals blocked. */ - sigprocmask(SIG_SETMASK, &allowed_mask, NULL); - svc_process(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; - killsig = signo; - } /* Clear signals before calling svc_exit_thread() */ flush_signals(current); - lock_kernel(); - + mutex_lock(&nfsd_mutex); nfsdstats.th_cnt --; out: @@ -490,8 +525,9 @@ out: svc_exit_thread(rqstp); /* Release module */ - unlock_kernel(); + mutex_unlock(&nfsd_mutex); module_put_and_exit(0); + return 0; } static __be32 map_new_errors(u32 vers, __be32 nfserr) @@ -546,8 +582,6 @@ nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp) /* 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_jukebox && rqstp->rq_vers == 2) - nfserr = nfserr_dropit; if (nfserr == nfserr_dropit) { dprintk("nfsd: Dropping request; may be revisited later\n"); nfsd_cache_update(rqstp, RC_NOCACHE, NULL); @@ -576,3 +610,28 @@ nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp) nfsd_cache_update(rqstp, proc->pc_cachetype, statp + 1); return 1; } + +int nfsd_pool_stats_open(struct inode *inode, struct file *file) +{ + int ret; + mutex_lock(&nfsd_mutex); + if (nfsd_serv == NULL) { + mutex_unlock(&nfsd_mutex); + return -ENODEV; + } + /* bump up the psudo refcount while traversing */ + svc_get(nfsd_serv); + ret = svc_pool_stats_open(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); + mutex_lock(&nfsd_mutex); + /* this function really, really should have been called svc_put() */ + svc_destroy(nfsd_serv); + mutex_unlock(&nfsd_mutex); + return ret; +}