Import changes from OpenSolaris that provide

- better ACL caching and speedup of ACL permission checks
- faster handling of stat()
- lowered mutex contention in the read/writer lock (rrwlock)
- several related bugfixes

Detailed information (OpenSolaris onnv changesets and Bug IDs):

9749:105f407a2680
6802734	Support for Access Based Enumeration (not used on FreeBSD)
6844861	inconsistent xattr readdir behavior with too-small buffer

9866:ddc5f1d8eb4e
6848431	zfs with rstchown=0 or file_chown_self privilege allows user to "take" ownership

9981:b4907297e740
6775100	stat() performance on files on zfs should be improved
6827779	rrwlock is overly protective of its counters

10143:d2d432dfe597
6857433	memory leaks found at: zfs_acl_alloc/zfs_acl_node_alloc
6860318	truncate() on zfsroot succeeds when file has a component of its path set without access permission

10232:f37b85f7e03e
6865875	zfs sometimes incorrectly giving search access to a dir

10250:b179ceb34b62
6867395	zpool_upgrade_007_pos testcase panic'd with BAD TRAP: type=e (#pf Page fault)

10269:2788675568fd
6868276	zfs_rezget() can be hazardous when znode has a cached ACL

10295:f7a18a1e9610
6870564	panic in zfs_getsecattr

Approved by:	delphij (mentor)
Obtained from:	OpenSolaris (multiple Bug IDs)
MFC after:	2 weeks

1 files changed, 24 insertions, 0 deletions

diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_znode.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_znode.c
index 7b50f24..dbee467 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_znode.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_znode.c
@@ -177,6 +177,7 @@ zfs_znode_cache_constructor(void *buf, void *arg, int kmflags)
 
 	zp->z_dbuf = NULL;
 	zp->z_dirlocks = NULL;
+	zp->z_acl_cached = NULL;
 	return (0);
 }
 
@@ -199,6 +200,7 @@ zfs_znode_cache_destructor(void *buf, void *arg)
 
 	ASSERT(zp->z_dbuf == NULL);
 	ASSERT(zp->z_dirlocks == NULL);
+	ASSERT(zp->z_acl_cached == NULL);
 }
 
 #ifdef	ZNODE_STATS
@@ -244,6 +246,15 @@ zfs_znode_move_impl(znode_t *ozp, znode_t *nzp)
 	nzp->z_phys = ozp->z_phys;
 	nzp->z_dbuf = ozp->z_dbuf;
 
+	/*
+	 * Since this is just an idle znode and kmem is already dealing with
+	 * memory pressure, release any cached ACL.
+	 */
+	if (ozp->z_acl_cached) {
+		zfs_acl_free(ozp->z_acl_cached);
+		ozp->z_acl_cached = NULL;
+	}
+
 	/* Update back pointers. */
 	(void) dmu_buf_update_user(nzp->z_dbuf, ozp, nzp, &nzp->z_phys,
 	    znode_evict_error);
@@ -497,6 +508,7 @@ zfs_znode_dmu_init(zfsvfs_t *zfsvfs, znode_t *zp, dmu_buf_t *db)
 	mutex_enter(&zp->z_lock);
 
 	ASSERT(zp->z_dbuf == NULL);
+	ASSERT(zp->z_acl_cached == NULL);
 	zp->z_dbuf = db;
 	nzp = dmu_buf_set_user_ie(db, zp, &zp->z_phys, znode_evict_error);
 
@@ -980,6 +992,13 @@ zfs_rezget(znode_t *zp)
 		return (EIO);
 	}
 
+	mutex_enter(&zp->z_acl_lock);
+	if (zp->z_acl_cached) {
+		zfs_acl_free(zp->z_acl_cached);
+		zp->z_acl_cached = NULL;
+	}
+	mutex_exit(&zp->z_acl_lock);
+
 	zfs_znode_dmu_init(zfsvfs, zp, db);
 	zp->z_unlinked = (zp->z_phys->zp_links == 0);
 	zp->z_blksz = doi.doi_data_block_size;
@@ -1065,6 +1084,11 @@ zfs_znode_free(znode_t *zp)
 	list_remove(&zfsvfs->z_all_znodes, zp);
 	mutex_exit(&zfsvfs->z_znodes_lock);
 
+	if (zp->z_acl_cached) {
+		zfs_acl_free(zp->z_acl_cached);
+		zp->z_acl_cached = NULL;
+	}
+
 	kmem_cache_free(znode_cache, zp);
 
 	VFS_RELE(zfsvfs->z_vfs);