linux-nfs.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: "J. Bruce Fields" <bfields@redhat.com>
To: Jeff Layton <jlayton@redhat.com>
Cc: linux-nfs@vger.kernel.org, Jeff Layton <jlayton@redhat.com>,
	"J. Bruce Fields" <bfields@redhat.com>
Subject: [PATCH 1/7] nfsd4: fix v4 state shutdown error paths
Date: Wed, 21 Jul 2010 19:26:45 -0400	[thread overview]
Message-ID: <1279754811-8328-1-git-send-email-bfields@redhat.com> (raw)
In-Reply-To: <20100721232432.GA6689@fieldses.org>

From: Jeff Layton <jlayton@redhat.com>

If someone tries to shut down the laundry_wq while it isn't up it'll
cause an oops.

This can happen because write_ports can create a nfsd_svc before we
really start the nfs server, and we may fail before the server is ever
started.

Also make sure state is shutdown on error paths in nfsd_svc().

Use a common global nfsd_up flag instead of nfs4_init, and create common
helper functions for nfsd start/shutdown, as there will be other work
that we want done only when we the number of nfsd threads transitions
between zero and nonzero.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 fs/nfsd/nfs4state.c |   12 +-----------
 fs/nfsd/nfssvc.c    |   51 ++++++++++++++++++++++++++++++++++++++++++---------
 2 files changed, 43 insertions(+), 20 deletions(-)

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 182448f..9cc3b78 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -51,7 +51,6 @@ static time_t boot_time;
 static u32 current_ownerid = 1;
 static u32 current_fileid = 1;
 static u32 current_delegid = 1;
-static u32 nfs4_init;
 static stateid_t zerostateid;             /* bits all 0 */
 static stateid_t onestateid;              /* bits all 1 */
 static u64 current_sessionid = 1;
@@ -4071,16 +4070,8 @@ out_free_laundry:
 int
 nfs4_state_start(void)
 {
-	int ret;
-
-	if (nfs4_init)
-		return 0;
 	nfsd4_load_reboot_recovery_data();
-	ret = __nfs4_state_start();
-	if (ret)
-		return ret;
-	nfs4_init = 1;
-	return 0;
+	return __nfs4_state_start();
 }
 
 static void
@@ -4115,7 +4106,6 @@ __nfs4_state_shutdown(void)
 	}
 
 	nfsd4_shutdown_recdir();
-	nfs4_init = 0;
 }
 
 void
diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c
index 06b2a26..d7a4d7b 100644
--- a/fs/nfsd/nfssvc.c
+++ b/fs/nfsd/nfssvc.c
@@ -180,6 +180,31 @@ int nfsd_nrthreads(void)
 	return rv;
 }
 
+static bool nfsd_up = false;
+
+static int nfsd_startup(unsigned short port, int nrservs)
+{
+	int ret;
+
+	ret = nfs4_state_start();
+	nfsd_up = true;
+	return ret;
+}
+
+static void nfsd_shutdown(void)
+{
+	/*
+	 * write_ports can create the server without actually starting
+	 * any threads--if we get shut down before any threads are
+	 * started, then nfsd_last_thread will be run before any of this
+	 * other initialization has been done.
+	 */
+	if (!nfsd_up)
+		return;
+	nfs4_state_shutdown();
+	nfsd_up = false;
+}
+
 static void nfsd_last_thread(struct svc_serv *serv)
 {
 	/* When last nfsd thread exits we need to do some clean-up */
@@ -188,7 +213,7 @@ static void nfsd_last_thread(struct svc_serv *serv)
 		lockd_down();
 	nfsd_serv = NULL;
 	nfsd_racache_shutdown();
-	nfs4_state_shutdown();
+	nfsd_shutdown();
 
 	printk(KERN_WARNING "nfsd: last server has exited, flushing export "
 			    "cache\n");
@@ -380,6 +405,7 @@ int
 nfsd_svc(unsigned short port, int nrservs)
 {
 	int	error;
+	bool	first_thread;
 
 	mutex_lock(&nfsd_mutex);
 	dprintk("nfsd: creating service\n");
@@ -395,19 +421,23 @@ nfsd_svc(unsigned short port, int nrservs)
 	error =	nfsd_racache_init(2*nrservs);
 	if (error<0)
 		goto out;
-	error = nfs4_state_start();
-	if (error)
-		goto out;
+
+	first_thread = (nfsd_serv->sv_nrthreads == 0) && (nrservs != 0);
+
+	if (first_thread) {
+		error = nfsd_startup(port, nrservs);
+		if (error)
+			goto out;
+	}
 
 	nfsd_reset_versions();
 
 	error = nfsd_create_serv();
-
 	if (error)
-		goto out;
+		goto out_shutdown;
 	error = nfsd_init_socks(port);
 	if (error)
-		goto failure;
+		goto out_destroy;
 
 	error = svc_set_num_threads(nfsd_serv, NULL, nrservs);
 	if (error == 0)
@@ -416,9 +446,12 @@ nfsd_svc(unsigned short port, int nrservs)
 		 * so subtract 1
 		 */
 		error = nfsd_serv->sv_nrthreads - 1;
- failure:
+out_destroy:
 	svc_destroy(nfsd_serv);		/* Release server */
- out:
+out_shutdown:
+	if (error < 0 && first_thread)
+		nfsd_shutdown();
+out:
 	mutex_unlock(&nfsd_mutex);
 	return error;
 }
-- 
1.7.0.4


  reply	other threads:[~2010-07-21 23:27 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-07-21 13:21 [PATCH 5/5] nfsd: just keep single lockd reference for nfsd (try #4) Jeff Layton
2010-07-21 20:14 ` J. Bruce Fields
2010-07-21 23:24   ` J. Bruce Fields
2010-07-21 23:26     ` J. Bruce Fields [this message]
2010-07-21 23:26     ` [PATCH 2/7] nfsd: fix error handling when starting nfsd with rpcbind down J. Bruce Fields
2010-07-21 23:26     ` [PATCH 3/7] nfsd: fix error handling in __write_ports_addxprt J. Bruce Fields
2010-07-21 23:26     ` [PATCH 4/7] nfsd: clean up nfsd_create_serv error handling J. Bruce Fields
2010-07-21 23:26     ` [PATCH 5/7] nfsd: just keep single lockd reference for nfsd J. Bruce Fields
2010-07-21 23:26     ` [PATCH 6/7] nfsd: move more into nfsd_startup() J. Bruce Fields
2010-07-21 23:26     ` [PATCH 7/7] nfsd: minor nfsd_svc() cleanup J. Bruce Fields
2010-07-22 17:40     ` [PATCH 5/5] nfsd: just keep single lockd reference for nfsd (try #4) Jeff Layton
     [not found]       ` <20100722134026.62091dc2-xSBYVWDuneFaJnirhKH9O4GKTjYczspe@public.gmane.org>
2010-07-23 12:55         ` J. Bruce Fields
2010-07-22 11:59   ` Staubach_Peter
2010-07-22 12:26     ` J. Bruce Fields
2010-07-22 12:36     ` Jeff Layton

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1279754811-8328-1-git-send-email-bfields@redhat.com \
    --to=bfields@redhat.com \
    --cc=jlayton@redhat.com \
    --cc=linux-nfs@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).