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| author | kib <kib@FreeBSD.org> | 2014-08-29 09:04:24 +0000 |
|---|---|---|
| committer | kib <kib@FreeBSD.org> | 2014-08-29 09:04:24 +0000 |
| commit | ece271f9c965d80e212b6848db0c2ad971d20948 (patch) | |
| tree | 2c066c1760b11960131e12eabe20b57ba1218b9b /sys/ufs | |
| parent | d7608dcfd61cd04f000829f02e61aafac80bed95 (diff) | |
| download | FreeBSD-src-ece271f9c965d80e212b6848db0c2ad971d20948.zip FreeBSD-src-ece271f9c965d80e212b6848db0c2ad971d20948.tar.gz | |
Direct access to the quota files, in particular, lookup, causes lock
conflict with the quota metadata access. Mark quota vnode lock as
recursive and always exclusive to avoid the problem.
Reported by: hrs
Tested by: hrs, pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Diffstat (limited to 'sys/ufs')
| -rw-r--r-- | sys/ufs/ufs/ufs_quota.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/sys/ufs/ufs/ufs_quota.c b/sys/ufs/ufs/ufs_quota.c index f8bc981..a6e139a 100644 --- a/sys/ufs/ufs/ufs_quota.c +++ b/sys/ufs/ufs/ufs_quota.c @@ -557,8 +557,21 @@ quotaon(struct thread *td, struct mount *mp, int type, void *fname) if (*vpp != vp) quotaoff1(td, mp, type); + /* + * When the directory vnode containing the quota file is + * inactivated, due to the shared lookup of the quota file + * vput()ing the dvp, the qsyncvp() call for the containing + * directory would try to acquire the quota lock exclusive. + * At the same time, lookup already locked the quota vnode + * shared. Mark the quota vnode lock as allowing recursion + * and automatically converting shared locks to exclusive. + * + * Also mark quota vnode as system. + */ vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); vp->v_vflag |= VV_SYSTEM; + VN_LOCK_AREC(vp); + VN_LOCK_DSHARE(vp); VOP_UNLOCK(vp, 0); *vpp = vp; /* |
