1 files changed, 519 insertions, 0 deletions

diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
new file mode 100644
index 000000000000..b82e470912e8
--- /dev/null
+++ b/fs/lockd/svc.c
@@ -0,0 +1,519 @@
+/*
+ * linux/fs/lockd/svc.c
+ *
+ * This is the central lockd service.
+ *
+ * FIXME: Separate the lockd NFS server functionality from the lockd NFS
+ *        client functionality. Oh why didn't Sun create two separate
+ *        services in the first place?
+ *
+ * Authors:     Olaf Kirch (okir@monad.swb.de)
+ *
+ * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sysctl.h>
+#include <linux/moduleparam.h>
+
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/in.h>
+#include <linux/uio.h>
+#include <linux/slab.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+
+#include <linux/sunrpc/types.h>
+#include <linux/sunrpc/stats.h>
+#include <linux/sunrpc/clnt.h>
+#include <linux/sunrpc/svc.h>
+#include <linux/sunrpc/svcsock.h>
+#include <linux/lockd/lockd.h>
+#include <linux/nfs.h>
+
+#define NLMDBG_FACILITY         NLMDBG_SVC
+#define LOCKD_BUFSIZE           (1024 + NLMSVC_XDRSIZE)
+#define ALLOWED_SIGS            (sigmask(SIGKILL))
+
+static struct svc_program       nlmsvc_program;
+
+struct nlmsvc_binding *         nlmsvc_ops;
+EXPORT_SYMBOL(nlmsvc_ops);
+
+static DECLARE_MUTEX(nlmsvc_sema);
+static unsigned int             nlmsvc_users;
+static pid_t                    nlmsvc_pid;
+int                             nlmsvc_grace_period;
+unsigned long                   nlmsvc_timeout;
+
+static DECLARE_MUTEX_LOCKED(lockd_start);
+static DECLARE_WAIT_QUEUE_HEAD(lockd_exit);
+
+/*
+ * These can be set at insmod time (useful for NFS as root filesystem),
+ * and also changed through the sysctl interface.  -- Jamie Lokier, Aug 2003
+ */
+static unsigned long            nlm_grace_period;
+static unsigned long            nlm_timeout = LOCKD_DFLT_TIMEO;
+static int                      nlm_udpport, nlm_tcpport;
+
+/*
+ * Constants needed for the sysctl interface.
+ */
+static const unsigned long      nlm_grace_period_min = 0;
+static const unsigned long      nlm_grace_period_max = 240;
+static const unsigned long      nlm_timeout_min = 3;
+static const unsigned long      nlm_timeout_max = 20;
+static const int                nlm_port_min = 0, nlm_port_max = 65535;
+
+static struct ctl_table_header * nlm_sysctl_table;
+
+static unsigned long set_grace_period(void)
+{
+        unsigned long grace_period;
+
+        /* Note: nlm_timeout should always be nonzero */
+        if (nlm_grace_period)
+                grace_period = ((nlm_grace_period + nlm_timeout - 1)
+                                / nlm_timeout) * nlm_timeout * HZ;
+        else
+                grace_period = nlm_timeout * 5 * HZ;
+        nlmsvc_grace_period = 1;
+        return grace_period + jiffies;
+}
+
+static inline void clear_grace_period(void)
+{
+        nlmsvc_grace_period = 0;
+}
+
+/*
+ * This is the lockd kernel thread
+ */
+static void
+lockd(struct svc_rqst *rqstp)
+{
+        struct svc_serv *serv = rqstp->rq_server;
+        int             err = 0;
+        unsigned long grace_period_expire;
+
+        /* Lock module and set up kernel thread */
+        /* lockd_up is waiting for us to startup, so will
+         * be holding a reference to this module, so it
+         * is safe to just claim another reference
+         */
+        __module_get(THIS_MODULE);
+        lock_kernel();
+
+        /*
+         * Let our maker know we're running.
+         */
+        nlmsvc_pid = current->pid;
+        up(&lockd_start);
+
+        daemonize("lockd");
+
+        /* Process request with signals blocked, but allow SIGKILL.  */
+        allow_signal(SIGKILL);
+
+        /* kick rpciod */
+        rpciod_up();
+
+        dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
+
+        if (!nlm_timeout)
+                nlm_timeout = LOCKD_DFLT_TIMEO;
+        nlmsvc_timeout = nlm_timeout * HZ;
+
+        grace_period_expire = set_grace_period();
+
+        /*
+         * The main request loop. We don't terminate until the last
+         * NFS mount or NFS daemon has gone away, and we've been sent a
+         * signal, or else another process has taken over our job.
+         */
+        while ((nlmsvc_users || !signalled()) && nlmsvc_pid == current->pid) {
+                long timeout = MAX_SCHEDULE_TIMEOUT;
+
+                if (signalled()) {
+                        flush_signals(current);
+                        if (nlmsvc_ops) {
+                                nlmsvc_invalidate_all();
+                                grace_period_expire = set_grace_period();
+                        }
+                }
+
+                /*
+                 * Retry any blocked locks that have been notified by
+                 * the VFS. Don't do this during grace period.
+                 * (Theoretically, there shouldn't even be blocked locks
+                 * during grace period).
+                 */
+                if (!nlmsvc_grace_period) {
+                        timeout = nlmsvc_retry_blocked();
+                } else if (time_before(grace_period_expire, jiffies))
+                        clear_grace_period();
+
+                /*
+                 * Find a socket with data available and call its
+                 * recvfrom routine.
+                 */
+                err = svc_recv(serv, rqstp, timeout);
+                if (err == -EAGAIN || err == -EINTR)
+                        continue;
+                if (err < 0) {
+                        printk(KERN_WARNING
+                               "lockd: terminating on error %d\n",
+                               -err);
+                        break;
+                }
+
+                dprintk("lockd: request from %08x\n",
+                        (unsigned)ntohl(rqstp->rq_addr.sin_addr.s_addr));
+
+                svc_process(serv, rqstp);
+
+        }
+
+        /*
+         * Check whether there's a new lockd process before
+         * shutting down the hosts and clearing the slot.
+         */
+        if (!nlmsvc_pid || current->pid == nlmsvc_pid) {
+                if (nlmsvc_ops)
+                        nlmsvc_invalidate_all();
+                nlm_shutdown_hosts();
+                nlmsvc_pid = 0;
+        } else
+                printk(KERN_DEBUG
+                        "lockd: new process, skipping host shutdown\n");
+        wake_up(&lockd_exit);
+                
+        /* Exit the RPC thread */
+        svc_exit_thread(rqstp);
+
+        /* release rpciod */
+        rpciod_down();
+
+        /* Release module */
+        unlock_kernel();
+        module_put_and_exit(0);
+}
+
+/*
+ * Bring up the lockd process if it's not already up.
+ */
+int
+lockd_up(void)
+{
+        static int              warned;
+        struct svc_serv *       serv;
+        int                     error = 0;
+
+        down(&nlmsvc_sema);
+        /*
+         * Unconditionally increment the user count ... this is
+         * the number of clients who _want_ a lockd process.
+         */
+        nlmsvc_users++; 
+        /*
+         * Check whether we're already up and running.
+         */
+        if (nlmsvc_pid)
+                goto out;
+
+        /*
+         * Sanity check: if there's no pid,
+         * we should be the first user ...
+         */
+        if (nlmsvc_users > 1)
+                printk(KERN_WARNING
+                        "lockd_up: no pid, %d users??\n", nlmsvc_users);
+
+        error = -ENOMEM;
+        serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE);
+        if (!serv) {
+                printk(KERN_WARNING "lockd_up: create service failed\n");
+                goto out;
+        }
+
+        if ((error = svc_makesock(serv, IPPROTO_UDP, nlm_udpport)) < 0 
+#ifdef CONFIG_NFSD_TCP
+         || (error = svc_makesock(serv, IPPROTO_TCP, nlm_tcpport)) < 0
+#endif
+                ) {
+                if (warned++ == 0) 
+                        printk(KERN_WARNING
+                                "lockd_up: makesock failed, error=%d\n", error);
+                goto destroy_and_out;
+        } 
+        warned = 0;
+
+        /*
+         * Create the kernel thread and wait for it to start.
+         */
+        error = svc_create_thread(lockd, serv);
+        if (error) {
+                printk(KERN_WARNING
+                        "lockd_up: create thread failed, error=%d\n", error);
+                goto destroy_and_out;
+        }
+        down(&lockd_start);
+
+        /*
+         * Note: svc_serv structures have an initial use count of 1,
+         * so we exit through here on both success and failure.
+         */
+destroy_and_out:
+        svc_destroy(serv);
+out:
+        up(&nlmsvc_sema);
+        return error;
+}
+EXPORT_SYMBOL(lockd_up);
+
+/*
+ * Decrement the user count and bring down lockd if we're the last.
+ */
+void
+lockd_down(void)
+{
+        static int warned;
+
+        down(&nlmsvc_sema);
+        if (nlmsvc_users) {
+                if (--nlmsvc_users)
+                        goto out;
+        } else
+                printk(KERN_WARNING "lockd_down: no users! pid=%d\n", nlmsvc_pid);
+
+        if (!nlmsvc_pid) {
+                if (warned++ == 0)
+                        printk(KERN_WARNING "lockd_down: no lockd running.\n"); 
+                goto out;
+        }
+        warned = 0;
+
+        kill_proc(nlmsvc_pid, SIGKILL, 1);
+        /*
+         * Wait for the lockd process to exit, but since we're holding
+         * the lockd semaphore, we can't wait around forever ...
+         */
+        clear_thread_flag(TIF_SIGPENDING);
+        interruptible_sleep_on_timeout(&lockd_exit, HZ);
+        if (nlmsvc_pid) {
+                printk(KERN_WARNING 
+                        "lockd_down: lockd failed to exit, clearing pid\n");
+                nlmsvc_pid = 0;
+        }
+        spin_lock_irq(&current->sighand->siglock);
+        recalc_sigpending();
+        spin_unlock_irq(&current->sighand->siglock);
+out:
+        up(&nlmsvc_sema);
+}
+EXPORT_SYMBOL(lockd_down);
+
+/*
+ * Sysctl parameters (same as module parameters, different interface).
+ */
+
+/* Something that isn't CTL_ANY, CTL_NONE or a value that may clash. */
+#define CTL_UNNUMBERED          -2
+
+static ctl_table nlm_sysctls[] = {
+        {
+                .ctl_name       = CTL_UNNUMBERED,
+                .procname       = "nlm_grace_period",
+                .data           = &nlm_grace_period,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = &proc_doulongvec_minmax,
+                .extra1         = (unsigned long *) &nlm_grace_period_min,
+                .extra2         = (unsigned long *) &nlm_grace_period_max,
+        },
+        {
+                .ctl_name       = CTL_UNNUMBERED,
+                .procname       = "nlm_timeout",
+                .data           = &nlm_timeout,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = &proc_doulongvec_minmax,
+                .extra1         = (unsigned long *) &nlm_timeout_min,
+                .extra2         = (unsigned long *) &nlm_timeout_max,
+        },
+        {
+                .ctl_name       = CTL_UNNUMBERED,
+                .procname       = "nlm_udpport",
+                .data           = &nlm_udpport,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec_minmax,
+                .extra1         = (int *) &nlm_port_min,
+                .extra2         = (int *) &nlm_port_max,
+        },
+        {
+                .ctl_name       = CTL_UNNUMBERED,
+                .procname       = "nlm_tcpport",
+                .data           = &nlm_tcpport,
+                .maxlen         = sizeof(int),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec_minmax,
+                .extra1         = (int *) &nlm_port_min,
+                .extra2         = (int *) &nlm_port_max,
+        },
+        { .ctl_name = 0 }
+};
+
+static ctl_table nlm_sysctl_dir[] = {
+        {
+                .ctl_name       = CTL_UNNUMBERED,
+                .procname       = "nfs",
+                .mode           = 0555,
+                .child          = nlm_sysctls,
+        },
+        { .ctl_name = 0 }
+};
+
+static ctl_table nlm_sysctl_root[] = {
+        {
+                .ctl_name       = CTL_FS,
+                .procname       = "fs",
+                .mode           = 0555,
+                .child          = nlm_sysctl_dir,
+        },
+        { .ctl_name = 0 }
+};
+
+/*
+ * Module (and driverfs) parameters.
+ */
+
+#define param_set_min_max(name, type, which_strtol, min, max)           \
+static int param_set_##name(const char *val, struct kernel_param *kp)   \
+{                                                                       \
+        char *endp;                                                     \
+        __typeof__(type) num = which_strtol(val, &endp, 0);             \
+        if (endp == val || *endp || num < (min) || num > (max))         \
+                return -EINVAL;                                         \
+        *((int *) kp->arg) = num;                                       \
+        return 0;                                                       \
+}
+
+static inline int is_callback(u32 proc)
+{
+        return proc == NLMPROC_GRANTED
+                || proc == NLMPROC_GRANTED_MSG
+                || proc == NLMPROC_TEST_RES
+                || proc == NLMPROC_LOCK_RES
+                || proc == NLMPROC_CANCEL_RES
+                || proc == NLMPROC_UNLOCK_RES
+                || proc == NLMPROC_NSM_NOTIFY;
+}
+
+
+static int lockd_authenticate(struct svc_rqst *rqstp)
+{
+        rqstp->rq_client = NULL;
+        switch (rqstp->rq_authop->flavour) {
+                case RPC_AUTH_NULL:
+                case RPC_AUTH_UNIX:
+                        if (rqstp->rq_proc == 0)
+                                return SVC_OK;
+                        if (is_callback(rqstp->rq_proc)) {
+                                /* Leave it to individual procedures to
+                                 * call nlmsvc_lookup_host(rqstp)
+                                 */
+                                return SVC_OK;
+                        }
+                        return svc_set_client(rqstp);
+        }
+        return SVC_DENIED;
+}
+
+
+param_set_min_max(port, int, simple_strtol, 0, 65535)
+param_set_min_max(grace_period, unsigned long, simple_strtoul,
+                  nlm_grace_period_min, nlm_grace_period_max)
+param_set_min_max(timeout, unsigned long, simple_strtoul,
+                  nlm_timeout_min, nlm_timeout_max)
+
+MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
+MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
+MODULE_LICENSE("GPL");
+
+module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
+                  &nlm_grace_period, 0644);
+module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
+                  &nlm_timeout, 0644);
+module_param_call(nlm_udpport, param_set_port, param_get_int,
+                  &nlm_udpport, 0644);
+module_param_call(nlm_tcpport, param_set_port, param_get_int,
+                  &nlm_tcpport, 0644);
+
+/*
+ * Initialising and terminating the module.
+ */
+
+static int __init init_nlm(void)
+{
+        nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root, 0);
+        return nlm_sysctl_table ? 0 : -ENOMEM;
+}
+
+static void __exit exit_nlm(void)
+{
+        /* FIXME: delete all NLM clients */
+        nlm_shutdown_hosts();
+        unregister_sysctl_table(nlm_sysctl_table);
+}
+
+module_init(init_nlm);
+module_exit(exit_nlm);
+
+/*
+ * Define NLM program and procedures
+ */
+static struct svc_version       nlmsvc_version1 = {
+                .vs_vers        = 1,
+                .vs_nproc       = 17,
+                .vs_proc        = nlmsvc_procedures,
+                .vs_xdrsize     = NLMSVC_XDRSIZE,
+};
+static struct svc_version       nlmsvc_version3 = {
+                .vs_vers        = 3,
+                .vs_nproc       = 24,
+                .vs_proc        = nlmsvc_procedures,
+                .vs_xdrsize     = NLMSVC_XDRSIZE,
+};
+#ifdef CONFIG_LOCKD_V4
+static struct svc_version       nlmsvc_version4 = {
+                .vs_vers        = 4,
+                .vs_nproc       = 24,
+                .vs_proc        = nlmsvc_procedures4,
+                .vs_xdrsize     = NLMSVC_XDRSIZE,
+};
+#endif
+static struct svc_version *     nlmsvc_version[] = {
+        [1] = &nlmsvc_version1,
+        [3] = &nlmsvc_version3,
+#ifdef CONFIG_LOCKD_V4
+        [4] = &nlmsvc_version4,
+#endif
+};
+
+static struct svc_stat          nlmsvc_stats;
+
+#define NLM_NRVERS      (sizeof(nlmsvc_version)/sizeof(nlmsvc_version[0]))
+static struct svc_program       nlmsvc_program = {
+        .pg_prog                = NLM_PROGRAM,          /* program number */
+        .pg_nvers               = NLM_NRVERS,           /* number of entries in nlmsvc_version */
+        .pg_vers                = nlmsvc_version,       /* version table */
+        .pg_name                = "lockd",              /* service name */
+        .pg_class               = "nfsd",               /* share authentication with nfsd */
+        .pg_stats               = &nlmsvc_stats,        /* stats table */
+        .pg_authenticate = &lockd_authenticate  /* export authentication */
+};