X-Git-Url: https://git.camperquake.de/gitweb.cgi?a=blobdiff_plain;f=module%2Fzfs%2Fzfs_sa.c;h=f35f6f64cc41487c40ff0db58c6c6d0d14510d8f;hb=ec2626ad3f695a2ced3946c4197ef64cbcac4959;hp=621c5f904e438addd02a2001497017b1270ebf96;hpb=4b787d75c869a7f633607ecb17f3a7c482a553d2;p=zfs.git

diff --git a/module/zfs/zfs_sa.c b/module/zfs/zfs_sa.c
index 621c5f9..f35f6f6 100644
--- a/module/zfs/zfs_sa.c
+++ b/module/zfs/zfs_sa.c
@@ -188,6 +188,7 @@ int
 zfs_sa_get_xattr(znode_t *zp)
 {
 	zfs_sb_t *zsb = ZTOZSB(zp);
+	sa_handle_t *sa;
 	char *obj;
 	int size;
 	int error;
@@ -196,8 +197,14 @@ zfs_sa_get_xattr(znode_t *zp)
 	ASSERT(!zp->z_xattr_cached);
 	ASSERT(zp->z_is_sa);
 
-	error = sa_size(zp->z_sa_hdl, SA_ZPL_DXATTR(zsb), &size);
+	error = sa_handle_get(zsb->z_os, zp->z_id, NULL, SA_HDL_PRIVATE, &sa);
+	if (error)
+		return (error);
+
+	error = sa_size(sa, SA_ZPL_DXATTR(zsb), &size);
 	if (error) {
+		sa_handle_destroy(sa);
+
 		if (error == ENOENT)
 			return nvlist_alloc(&zp->z_xattr_cached,
 			    NV_UNIQUE_NAME, KM_SLEEP);
@@ -207,11 +214,12 @@ zfs_sa_get_xattr(znode_t *zp)
 
 	obj = sa_spill_alloc(KM_SLEEP);
 
-	error = sa_lookup(zp->z_sa_hdl, SA_ZPL_DXATTR(zsb), obj, size);
+	error = sa_lookup(sa, SA_ZPL_DXATTR(zsb), obj, size);
 	if (error == 0)
 		error = nvlist_unpack(obj, size, &zp->z_xattr_cached, KM_SLEEP);
 
 	sa_spill_free(obj);
+	sa_handle_destroy(sa);
 
 	return (error);
 }
@@ -220,6 +228,7 @@ int
 zfs_sa_set_xattr(znode_t *zp)
 {
 	zfs_sb_t *zsb = ZTOZSB(zp);
+	sa_handle_t *sa;
 	dmu_tx_t *tx;
 	char *obj;
 	size_t size;
@@ -240,16 +249,30 @@ zfs_sa_set_xattr(znode_t *zp)
 	if (error)
 		goto out_free;
 
+	/*
+	 * A private SA handle must be used to ensure we can drop the hold
+	 * on the spill block prior to calling dmu_tx_commit().  If we call
+	 * dmu_tx_commit() before sa_handle_destroy(), then our hold will
+	 * trigger a copy of the buffer at txg sync time.  This is done to
+	 * prevent data from leaking in to the syncing txg.  As a result
+	 * the original dirty spill block will be remain dirty in the arc
+	 * while the copy is written and laundered.
+	 */
+	error = sa_handle_get(zsb->z_os, zp->z_id, NULL, SA_HDL_PRIVATE, &sa);
+	if (error)
+		goto out_free;
+
 	tx = dmu_tx_create(zsb->z_os);
 	dmu_tx_hold_sa_create(tx, size);
-	dmu_tx_hold_sa(tx, zp->z_sa_hdl, B_TRUE);
+	dmu_tx_hold_sa(tx, sa, B_TRUE);
 
 	error = dmu_tx_assign(tx, TXG_WAIT);
 	if (error) {
 		dmu_tx_abort(tx);
+		sa_handle_destroy(sa);
 	} else {
-		error = sa_update(zp->z_sa_hdl, SA_ZPL_DXATTR(zsb),
-		    obj, size, tx);
+		error = sa_update(sa, SA_ZPL_DXATTR(zsb), obj, size, tx);
+		sa_handle_destroy(sa);
 		if (error)
 			dmu_tx_abort(tx);
 		else