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-rw-r--r--fs/lockd/svc.c519
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 */
+};
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