File 0001-mountd-remove-dev_missing-checks.patch of Package nfs-utils

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File 0001-mountd-remove-dev_missing-checks.patch of Package nfs-utils (Revision 894d2a59f9cb909141d07bcd78e951f5)

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From 6a914efcf3669afba27722584a92d70dfdc0cae4 Mon Sep 17 00:00:00 2001
From: NeilBrown <neilb@suse.com>
Date: Wed, 13 Jul 2016 11:44:34 +1000
Subject: [PATCH] mountd: remove 'dev_missing' checks

I now think this was a mistaken idea.

If a filesystem is exported with the "mountpoint" or "mp" option, it
should only be exported if the directory is a mount point.
The intention is that if there is a problem with one filesystem on a
server, the others can still be exported, but clients won't incorrectly
see the empty directory on the parent.

It is easy to handle this correctly for NFSv3 MOUNT requests, but what
is the correct behavior if a client already has the filesystem mounted
and so has a filehandle.  Maybe the server rebooted and came back with
one device missing.  What should the client see?

The "dev_missing" code tries to detect this case and causes the server
to respond with silence rather than ESTALE.  The idea was that the
client would retry and when (or if) the filesystem came back, service
would be transparently restored.

The problem with this is that arbitrary long delays are not what people
would expect, and can be quite annoying.  ESTALE, while unpleasant, it
at least easily understood.  A device disappearing is a fairly
significant event and hiding it doesn't really serve anyone.

So: remove the code and allow ESTALE.

Signed-off-by: NeilBrown <neilb@suse.com>
---
 utils/mountd/cache.c |   12 ------------
 1 file changed, 12 deletions(-)

--- a/utils/mountd/cache.c
+++ b/utils/mountd/cache.c
@@ -597,7 +597,6 @@ static void nfsd_fh(FILE *f)
 	char *found_path = NULL;
 	nfs_export *exp;
 	int i;
-	int dev_missing = 0;
 
 	if (readline(fileno(f), &lbuf, &lbuflen) != 1)
 		return;
@@ -661,11 +660,6 @@ static void nfsd_fh(FILE *f)
 			if (!is_ipaddr_client(dom)
 					&& !namelist_client_matches(exp, dom))
 				continue;
-			if (exp->m_export.e_mountpoint &&
-			    !is_mountpoint(exp->m_export.e_mountpoint[0]?
-					   exp->m_export.e_mountpoint:
-					   exp->m_export.e_path))
-				dev_missing ++;
 
 			if (!match_fsid(&parsed, exp, path))
 				continue;
@@ -708,12 +702,6 @@ static void nfsd_fh(FILE *f)
 		/* FIXME we need to make sure we re-visit this later */
 		goto out;
 	}
-	if (!found && dev_missing) {
-		/* The missing dev could be what we want, so just be
-		 * quite rather than returning stale yet
-		 */
-		goto out;
-	}
 
 	if (found)
 		if (cache_export_ent(dom, found, found_path) < 0)

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File 0001-mountd-remove-dev_missing-checks.patch of Package nfs-utils (Revision 894d2a59f9cb909141d07bcd78e951f5)

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