Merge branch 'for-3.18' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "Highlights:

   - support the NFSv4.2 SEEK operation (allowing clients to support
     SEEK_HOLE/SEEK_DATA), thanks to Anna.
   - end the grace period early in a number of cases, mitigating a
     long-standing annoyance, thanks to Jeff
   - improve SMP scalability, thanks to Trond"

* 'for-3.18' of git://linux-nfs.org/~bfields/linux: (55 commits)
  nfsd: eliminate "to_delegation" define
  NFSD: Implement SEEK
  NFSD: Add generic v4.2 infrastructure
  svcrdma: advertise the correct max payload
  nfsd: introduce nfsd4_callback_ops
  nfsd: split nfsd4_callback initialization and use
  nfsd: introduce a generic nfsd4_cb
  nfsd: remove nfsd4_callback.cb_op
  nfsd: do not clear rpc_resp in nfsd4_cb_done_sequence
  nfsd: fix nfsd4_cb_recall_done error handling
  nfsd4: clarify how grace period ends
  nfsd4: stop grace_time update at end of grace period
  nfsd: skip subsequent UMH "create" operations after the first one for v4.0 clients
  nfsd: set and test NFSD4_CLIENT_STABLE bit to reduce nfsdcltrack upcalls
  nfsd: serialize nfsdcltrack upcalls for a particular client
  nfsd: pass extra info in env vars to upcalls to allow for early grace period end
  nfsd: add a v4_end_grace file to /proc/fs/nfsd
  lockd: add a /proc/fs/lockd/nlm_end_grace file
  nfsd: reject reclaim request when client has already sent RECLAIM_COMPLETE
  nfsd: remove redundant boot_time parm from grace_done client tracking op
  ...

fs/lockd/Makefile

@@ -5,6 +5,7 @@
 obj-$(CONFIG_LOCKD) += lockd.o
 
 lockd-objs-y := clntlock.o clntproc.o clntxdr.o host.o svc.o svclock.o \
-	        svcshare.o svcproc.o svcsubs.o mon.o xdr.o grace.o
+	        svcshare.o svcproc.o svcsubs.o mon.o xdr.o
 lockd-objs-$(CONFIG_LOCKD_V4) += clnt4xdr.o xdr4.o svc4proc.o
+lockd-objs-$(CONFIG_PROC_FS) += procfs.o
 lockd-objs		      := $(lockd-objs-y)

fs/lockd/grace.c

@@ -1,65 +0,0 @@
-/*
- * Common code for control of lockd and nfsv4 grace periods.
- */
-
-#include <linux/module.h>
-#include <linux/lockd/bind.h>
-#include <net/net_namespace.h>
-
-#include "netns.h"
-
-static DEFINE_SPINLOCK(grace_lock);
-
-/**
- * locks_start_grace
- * @lm: who this grace period is for
- *
- * A grace period is a period during which locks should not be given
- * out.  Currently grace periods are only enforced by the two lock
- * managers (lockd and nfsd), using the locks_in_grace() function to
- * check when they are in a grace period.
- *
- * This function is called to start a grace period.
- */
-void locks_start_grace(struct net *net, struct lock_manager *lm)
-{
-	struct lockd_net *ln = net_generic(net, lockd_net_id);
-
-	spin_lock(&grace_lock);
-	list_add(&lm->list, &ln->grace_list);
-	spin_unlock(&grace_lock);
-}
-EXPORT_SYMBOL_GPL(locks_start_grace);
-
-/**
- * locks_end_grace
- * @lm: who this grace period is for
- *
- * Call this function to state that the given lock manager is ready to
- * resume regular locking.  The grace period will not end until all lock
- * managers that called locks_start_grace() also call locks_end_grace().
- * Note that callers count on it being safe to call this more than once,
- * and the second call should be a no-op.
- */
-void locks_end_grace(struct lock_manager *lm)
-{
-	spin_lock(&grace_lock);
-	list_del_init(&lm->list);
-	spin_unlock(&grace_lock);
-}
-EXPORT_SYMBOL_GPL(locks_end_grace);
-
-/**
- * locks_in_grace
- *
- * Lock managers call this function to determine when it is OK for them
- * to answer ordinary lock requests, and when they should accept only
- * lock reclaims.
- */
-int locks_in_grace(struct net *net)
-{
-	struct lockd_net *ln = net_generic(net, lockd_net_id);
-
-	return !list_empty(&ln->grace_list);
-}
-EXPORT_SYMBOL_GPL(locks_in_grace);

fs/lockd/netns.h

@@ -11,7 +11,6 @@ struct lockd_net {
 
 	struct delayed_work grace_period_end;
 	struct lock_manager lockd_manager;
-	struct list_head grace_list;
 
 	spinlock_t nsm_clnt_lock;
 	unsigned int nsm_users;

fs/lockd/procfs.c

@@ -0,0 +1,92 @@
+/*
+ * Procfs support for lockd
+ *
+ * Copyright (c) 2014 Jeff Layton <jlayton@primarydata.com>
+ */
+
+#include <linux/fs.h>
+#include <linux/proc_fs.h>
+#include <linux/module.h>
+#include <linux/nsproxy.h>
+#include <net/net_namespace.h>
+
+#include "netns.h"
+#include "procfs.h"
+
+/*
+ * We only allow strings that start with 'Y', 'y', or '1'.
+ */
+static ssize_t
+nlm_end_grace_write(struct file *file, const char __user *buf, size_t size,
+		    loff_t *pos)
+{
+	char *data;
+	struct lockd_net *ln = net_generic(current->nsproxy->net_ns,
+					   lockd_net_id);
+
+	if (size < 1)
+		return -EINVAL;
+
+	data = simple_transaction_get(file, buf, size);
+	if (IS_ERR(data))
+		return PTR_ERR(data);
+
+	switch(data[0]) {
+	case 'Y':
+	case 'y':
+	case '1':
+		locks_end_grace(&ln->lockd_manager);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return size;
+}
+
+static ssize_t
+nlm_end_grace_read(struct file *file, char __user *buf, size_t size,
+		   loff_t *pos)
+{
+	struct lockd_net *ln = net_generic(current->nsproxy->net_ns,
+					   lockd_net_id);
+	char resp[3];
+
+	resp[0] = list_empty(&ln->lockd_manager.list) ? 'Y' : 'N';
+	resp[1] = '\n';
+	resp[2] = '\0';
+
+	return simple_read_from_buffer(buf, size, pos, resp, sizeof(resp));
+}
+
+static const struct file_operations lockd_end_grace_operations = {
+	.write		= nlm_end_grace_write,
+	.read		= nlm_end_grace_read,
+	.llseek		= default_llseek,
+	.release	= simple_transaction_release,
+	.owner		= THIS_MODULE,
+};
+
+int __init
+lockd_create_procfs(void)
+{
+	struct proc_dir_entry *entry;
+
+	entry = proc_mkdir("fs/lockd", NULL);
+	if (!entry)
+		return -ENOMEM;
+	entry = proc_create("nlm_end_grace", S_IRUGO|S_IWUSR, entry,
+				 &lockd_end_grace_operations);
+	if (!entry) {
+		remove_proc_entry("fs/lockd", NULL);
+		return -ENOMEM;
+	}
+	return 0;
+}
+
+void __exit
+lockd_remove_procfs(void)
+{
+	remove_proc_entry("fs/lockd/nlm_end_grace", NULL);
+	remove_proc_entry("fs/lockd", NULL);
+}

fs/lockd/procfs.h

@@ -0,0 +1,28 @@
+/*
+ * Procfs support for lockd
+ *
+ * Copyright (c) 2014 Jeff Layton <jlayton@primarydata.com>
+ */
+#ifndef _LOCKD_PROCFS_H
+#define _LOCKD_PROCFS_H
+
+#include <linux/kconfig.h>
+
+#if IS_ENABLED(CONFIG_PROC_FS)
+int lockd_create_procfs(void);
+void lockd_remove_procfs(void);
+#else
+static inline int
+lockd_create_procfs(void)
+{
+	return 0;
+}
+
+static inline void
+lockd_remove_procfs(void)
+{
+	return;
+}
+#endif /* IS_ENABLED(CONFIG_PROC_FS) */
+
+#endif /* _LOCKD_PROCFS_H */

fs/lockd/svc.c

@@ -36,6 +36,7 @@
 #include <linux/nfs.h>
 
 #include "netns.h"
+#include "procfs.h"
 
 #define NLMDBG_FACILITY		NLMDBG_SVC
 #define LOCKD_BUFSIZE		(1024 + NLMSVC_XDRSIZE)
@@ -304,13 +305,16 @@ static int lockd_start_svc(struct svc_serv *serv)
 	svc_sock_update_bufs(serv);
 	serv->sv_maxconn = nlm_max_connections;
 
-	nlmsvc_task = kthread_run(lockd, nlmsvc_rqst, "%s", serv->sv_name);
+	nlmsvc_task = kthread_create(lockd, nlmsvc_rqst, "%s", serv->sv_name);
 	if (IS_ERR(nlmsvc_task)) {
 		error = PTR_ERR(nlmsvc_task);
 		printk(KERN_WARNING
 			"lockd_up: kthread_run failed, error=%d\n", error);
 		goto out_task;
 	}
+	nlmsvc_rqst->rq_task = nlmsvc_task;
+	wake_up_process(nlmsvc_task);
+
 	dprintk("lockd_up: service started\n");
 	return 0;
 
@@ -581,7 +585,7 @@ static int lockd_init_net(struct net *net)
 	struct lockd_net *ln = net_generic(net, lockd_net_id);
 
 	INIT_DELAYED_WORK(&ln->grace_period_end, grace_ender);
-	INIT_LIST_HEAD(&ln->grace_list);
+	INIT_LIST_HEAD(&ln->lockd_manager.list);
 	spin_lock_init(&ln->nsm_clnt_lock);
 	return 0;
 }
@@ -615,8 +619,15 @@ static int __init init_nlm(void)
 	err = register_pernet_subsys(&lockd_net_ops);
 	if (err)
 		goto err_pernet;
+
+	err = lockd_create_procfs();
+	if (err)
+		goto err_procfs;
+
 	return 0;
 
+err_procfs:
+	unregister_pernet_subsys(&lockd_net_ops);
 err_pernet:
 #ifdef CONFIG_SYSCTL
 	unregister_sysctl_table(nlm_sysctl_table);
@@ -629,6 +640,7 @@ static void __exit exit_nlm(void)
 {
 	/* FIXME: delete all NLM clients */
 	nlm_shutdown_hosts();
+	lockd_remove_procfs();
 	unregister_pernet_subsys(&lockd_net_ops);
 #ifdef CONFIG_SYSCTL
 	unregister_sysctl_table(nlm_sysctl_table);