svn commit: r248233 - in stable/9/sys: sys ufs/ffs ufs/ufs

Konstantin Belousov kib at FreeBSD.org
Wed Mar 13 10:01:07 UTC 2013


Author: kib
Date: Wed Mar 13 10:01:05 2013
New Revision: 248233
URL: http://svnweb.freebsd.org/changeset/base/248233

Log:
  MFC r247388:
  Work around the hold of references to the struct dquot by the freeblk
  workitems for some time at unmount.

Modified:
  stable/9/sys/sys/vnode.h
  stable/9/sys/ufs/ffs/ffs_softdep.c
  stable/9/sys/ufs/ffs/ffs_vfsops.c
  stable/9/sys/ufs/ufs/ufs_quota.c
Directory Properties:
  stable/9/sys/   (props changed)

Modified: stable/9/sys/sys/vnode.h
==============================================================================
--- stable/9/sys/sys/vnode.h	Wed Mar 13 09:54:11 2013	(r248232)
+++ stable/9/sys/sys/vnode.h	Wed Mar 13 10:01:05 2013	(r248233)
@@ -383,6 +383,7 @@ extern int		vttoif_tab[];
 #define	SKIPSYSTEM	0x0001	/* vflush: skip vnodes marked VSYSTEM */
 #define	FORCECLOSE	0x0002	/* vflush: force file closure */
 #define	WRITECLOSE	0x0004	/* vflush: only close writable files */
+#define	EARLYFLUSH	0x0008	/* vflush: early call for ffs_flushfiles */
 #define	V_SAVE		0x0001	/* vinvalbuf: sync file first */
 #define	V_ALT		0x0002	/* vinvalbuf: invalidate only alternate bufs */
 #define	V_NORMAL	0x0004	/* vinvalbuf: invalidate only regular bufs */

Modified: stable/9/sys/ufs/ffs/ffs_softdep.c
==============================================================================
--- stable/9/sys/ufs/ffs/ffs_softdep.c	Wed Mar 13 09:54:11 2013	(r248232)
+++ stable/9/sys/ufs/ffs/ffs_softdep.c	Wed Mar 13 10:01:05 2013	(r248233)
@@ -1914,7 +1914,12 @@ softdep_flushfiles(oldmnt, flags, td)
 	int flags;
 	struct thread *td;
 {
-	int error, depcount, loopcnt, retry_flush_count, retry;
+#ifdef QUOTA
+	struct ufsmount *ump;
+	int i;
+#endif
+	int error, early, depcount, loopcnt, retry_flush_count, retry;
+	int morework;
 
 	loopcnt = 10;
 	retry_flush_count = 3;
@@ -1932,7 +1937,9 @@ retry_flush:
 		 * Do another flush in case any vnodes were brought in
 		 * as part of the cleanup operations.
 		 */
-		if ((error = ffs_flushfiles(oldmnt, flags, td)) != 0)
+		early = retry_flush_count == 1 || (oldmnt->mnt_kern_flag &
+		    MNTK_UNMOUNT) == 0 ? 0 : EARLYFLUSH;
+		if ((error = ffs_flushfiles(oldmnt, flags | early, td)) != 0)
 			break;
 		if ((error = softdep_flushworklist(oldmnt, &depcount, td)) != 0 ||
 		    depcount == 0)
@@ -1956,7 +1963,17 @@ retry_flush:
 			MNT_ILOCK(oldmnt);
 			KASSERT((oldmnt->mnt_kern_flag & MNTK_NOINSMNTQ) != 0,
 			    ("softdep_flushfiles: !MNTK_NOINSMNTQ"));
-			if (oldmnt->mnt_nvnodelistsize > 0) {
+			morework = oldmnt->mnt_nvnodelistsize > 0;
+#ifdef QUOTA
+			ump = VFSTOUFS(oldmnt);
+			UFS_LOCK(ump);
+			for (i = 0; i < MAXQUOTAS; i++) {
+				if (ump->um_quotas[i] != NULLVP)
+					morework = 1;
+			}
+			UFS_UNLOCK(ump);
+#endif
+			if (morework) {
 				if (--retry_flush_count > 0) {
 					retry = 1;
 					loopcnt = 3;

Modified: stable/9/sys/ufs/ffs/ffs_vfsops.c
==============================================================================
--- stable/9/sys/ufs/ffs/ffs_vfsops.c	Wed Mar 13 09:54:11 2013	(r248232)
+++ stable/9/sys/ufs/ffs/ffs_vfsops.c	Wed Mar 13 10:01:05 2013	(r248233)
@@ -1355,9 +1355,10 @@ ffs_flushfiles(mp, flags, td)
 	struct thread *td;
 {
 	struct ufsmount *ump;
-	int error;
+	int qerror, error;
 
 	ump = VFSTOUFS(mp);
+	qerror = 0;
 #ifdef QUOTA
 	if (mp->mnt_flag & MNT_QUOTA) {
 		int i;
@@ -1365,11 +1366,19 @@ ffs_flushfiles(mp, flags, td)
 		if (error)
 			return (error);
 		for (i = 0; i < MAXQUOTAS; i++) {
-			quotaoff(td, mp, i);
+			error = quotaoff(td, mp, i);
+			if (error != 0) {
+				if ((flags & EARLYFLUSH) == 0)
+					return (error);
+				else
+					qerror = error;
+			}
 		}
+
 		/*
-		 * Here we fall through to vflush again to ensure
-		 * that we have gotten rid of all the system vnodes.
+		 * Here we fall through to vflush again to ensure that
+		 * we have gotten rid of all the system vnodes, unless
+		 * quotas must not be closed.
 		 */
 	}
 #endif
@@ -1384,11 +1393,21 @@ ffs_flushfiles(mp, flags, td)
 		 * that we have gotten rid of all the system vnodes.
 		 */
 	}
-        /*
-	 * Flush all the files.
+
+	/*
+	 * Do not close system files if quotas were not closed, to be
+	 * able to sync the remaining dquots.  The freeblks softupdate
+	 * workitems might hold a reference on a dquot, preventing
+	 * quotaoff() from completing.  Next round of
+	 * softdep_flushworklist() iteration should process the
+	 * blockers, allowing the next run of quotaoff() to finally
+	 * flush held dquots.
+	 *
+	 * Otherwise, flush all the files.
 	 */
-	if ((error = vflush(mp, 0, flags, td)) != 0)
+	if (qerror == 0 && (error = vflush(mp, 0, flags, td)) != 0)
 		return (error);
+
 	/*
 	 * Flush filesystem metadata.
 	 */

Modified: stable/9/sys/ufs/ufs/ufs_quota.c
==============================================================================
--- stable/9/sys/ufs/ufs/ufs_quota.c	Wed Mar 13 09:54:11 2013	(r248232)
+++ stable/9/sys/ufs/ufs/ufs_quota.c	Wed Mar 13 10:01:05 2013	(r248233)
@@ -80,7 +80,7 @@ static int dqopen(struct vnode *, struct
 static int dqget(struct vnode *,
 	u_long, struct ufsmount *, int, struct dquot **);
 static int dqsync(struct vnode *, struct dquot *);
-static void dqflush(struct vnode *);
+static int dqflush(struct vnode *);
 static int quotaoff1(struct thread *td, struct mount *mp, int type);
 static int quotaoff_inchange(struct thread *td, struct mount *mp, int type);
 
@@ -680,8 +680,12 @@ again:
 		vrele(vp);
 	}
 
-	dqflush(qvp);
-	/* Clear um_quotas before closing the quota vnode to prevent
+	error = dqflush(qvp);
+	if (error != 0)
+		return (error);
+
+	/*
+	 * Clear um_quotas before closing the quota vnode to prevent
 	 * access to the closed vnode from dqget/dqsync
 	 */
 	UFS_LOCK(ump);
@@ -1615,17 +1619,19 @@ out:
 /*
  * Flush all entries from the cache for a particular vnode.
  */
-static void
+static int
 dqflush(struct vnode *vp)
 {
 	struct dquot *dq, *nextdq;
 	struct dqhash *dqh;
+	int error;
 
 	/*
 	 * Move all dquot's that used to refer to this quota
 	 * file off their hash chains (they will eventually
 	 * fall off the head of the free list and be re-used).
 	 */
+	error = 0;
 	DQH_LOCK();
 	for (dqh = &dqhashtbl[dqhash]; dqh >= dqhashtbl; dqh--) {
 		for (dq = LIST_FIRST(dqh); dq; dq = nextdq) {
@@ -1633,12 +1639,15 @@ dqflush(struct vnode *vp)
 			if (dq->dq_ump->um_quotas[dq->dq_type] != vp)
 				continue;
 			if (dq->dq_cnt)
-				panic("dqflush: stray dquot");
-			LIST_REMOVE(dq, dq_hash);
-			dq->dq_ump = (struct ufsmount *)0;
+				error = EBUSY;
+			else {
+				LIST_REMOVE(dq, dq_hash);
+				dq->dq_ump = NULL;
+			}
 		}
 	}
 	DQH_UNLOCK();
+	return (error);
 }
 
 /*


More information about the svn-src-stable-9 mailing list