VFS: Add zfs_inode_update() helper

For the moment we have left ZFS unchanged and it updates many values
as part of the znode.  However, some of these values should be set
in the inode.  For the moment this is handled by adding a function
called zfs_inode_update() which updates the inode based on the znode.

This is considered a workaround until we can systematically go
through the ZFS code and have it directly update the inode.  At
which point zfs_update_inode() can be dropped entirely.  Keeping
two copies of the same data isn't only inefficient it's a breeding
ground for bugs.

include/sys/zfs_znode.h

@@ -326,6 +326,7 @@ extern dev_t	zfs_cmpldev(uint64_t);
 extern int	zfs_get_zplprop(objset_t *os, zfs_prop_t prop, uint64_t *value);
 extern int	zfs_get_stats(objset_t *os, nvlist_t *nv);
 extern void	zfs_znode_dmu_fini(znode_t *);
+extern void	zfs_inode_update(znode_t *);
 
 extern void zfs_log_create(zilog_t *zilog, dmu_tx_t *tx, uint64_t txtype,
     znode_t *dzp, znode_t *zp, char *name, vsecattr_t *, zfs_fuid_info_t *,

module/zfs/zfs_vfsops.c

@@ -1942,6 +1942,9 @@ zfs_vget(vfs_t *vfsp, vnode_t **vpp, fid_t *fidp)
 	}
 
 	*vpp = ZTOV(zp);
+	if (*vpp)
+		zfs_inode_update(VTOZ(*vpp));
+
 	ZFS_EXIT(zfsvfs);
 	return (0);
 }

module/zfs/zfs_vnops.c

@@ -564,6 +564,7 @@ out:
 	zfs_range_unlock(rl);
 
 	ZFS_ACCESSTIME_STAMP(zfsvfs, zp);
+	zfs_inode_update(zp);
 	ZFS_EXIT(zfsvfs);
 	return (error);
 }
@@ -938,6 +939,7 @@ again:
 	    zfsvfs->z_os->os_sync == ZFS_SYNC_ALWAYS)
 		zil_commit(zilog, zp->z_id);
 
+	zfs_inode_update(zp);
 	ZFS_EXIT(zfsvfs);
 	return (0);
 }
@@ -1266,8 +1268,12 @@ zfs_lookup(vnode_t *dvp, char *nm, vnode_t **vpp, struct pathname *pnp,
 	}
 
 	error = zfs_dirlook(zdp, nm, vpp, flags, direntflags, realpnp);
-	if (error == 0)
+	if (error == 0) {
+		if (*vpp)
+			zfs_inode_update(VTOZ(*vpp));
+
 		error = specvp_check(vpp, cr);
+	}
 
 	ZFS_EXIT(zfsvfs);
 	return (error);
@@ -1523,6 +1529,8 @@ out:
 		if (zp)
 			VN_RELE(ZTOV(zp));
 	} else {
+		zfs_inode_update(dzp);
+		zfs_inode_update(zp);
 		*vpp = ZTOV(zp);
 		error = specvp_check(vpp, cr);
 	}
@@ -1753,6 +1761,10 @@ out:
 		pn_free(realnmp);
 
 	zfs_dirent_unlock(dl);
+	zfs_inode_update(dzp);
+	zfs_inode_update(zp);
+	if (xzp)
+		zfs_inode_update(xzp);
 
 	if (!delete_now)
 		VN_RELE(vp);
@@ -1945,6 +1957,8 @@ top:
 	if (zfsvfs->z_os->os_sync == ZFS_SYNC_ALWAYS)
 		zil_commit(zilog, 0);
 
+	zfs_inode_update(dzp);
+	zfs_inode_update(zp);
 	ZFS_EXIT(zfsvfs);
 	return (0);
 }
@@ -2074,6 +2088,8 @@ out:
 	if (zfsvfs->z_os->os_sync == ZFS_SYNC_ALWAYS)
 		zil_commit(zilog, 0);
 
+	zfs_inode_update(dzp);
+	zfs_inode_update(zp);
 	ZFS_EXIT(zfsvfs);
 	return (error);
 }
@@ -3227,6 +3243,7 @@ out:
 	} else {
 		err2 = sa_bulk_update(zp->z_sa_hdl, bulk, count, tx);
 		dmu_tx_commit(tx);
+		 zfs_inode_update(zp);
 	}
 
 out2:
@@ -3674,13 +3691,19 @@ out:
 	zfs_dirent_unlock(sdl);
 	zfs_dirent_unlock(tdl);
 
+	zfs_inode_update(sdzp);
 	if (sdzp == tdzp)
 		rw_exit(&sdzp->z_name_lock);
 
+	if (sdzp != tdzp)
+		zfs_inode_update(tdzp);
 
+	zfs_inode_update(szp);
 	VN_RELE(ZTOV(szp));
-	if (tzp)
+	if (tzp) {
+		zfs_inode_update(tzp);
 		VN_RELE(ZTOV(tzp));
+	}
 
 	if (zfsvfs->z_os->os_sync == ZFS_SYNC_ALWAYS)
 		zil_commit(zilog, 0);
@@ -3828,6 +3851,9 @@ top:
 		txtype |= TX_CI;
 	zfs_log_symlink(zilog, tx, txtype, dzp, zp, name, link);
 
+	zfs_inode_update(dzp);
+	zfs_inode_update(zp);
+
 	zfs_acl_ids_free(&acl_ids);
 
 	dmu_tx_commit(tx);
@@ -3882,6 +3908,7 @@ zfs_readlink(vnode_t *vp, uio_t *uio, cred_t *cr, caller_context_t *ct)
 
 	ZFS_ACCESSTIME_STAMP(zfsvfs, zp);
 
+	zfs_inode_update(zp);
 	ZFS_EXIT(zfsvfs);
 	return (error);
 }
@@ -4037,6 +4064,8 @@ top:
 	if (zfsvfs->z_os->os_sync == ZFS_SYNC_ALWAYS)
 		zil_commit(zilog, 0);
 
+	zfs_inode_update(dzp);
+	zfs_inode_update(szp);
 	ZFS_EXIT(zfsvfs);
 	return (error);
 }

module/zfs/zfs_znode.c

@@ -521,6 +521,47 @@ zfs_znode_alloc(zfsvfs_t *zfsvfs, dmu_buf_t *db, int blksz,
 	return (zp);
 }
 
+/*
+ * Update the embedded inode given the znode.  We should work toward
+ * eliminating this function as soon as possible by removing values
+ * which are duplicated between the znode and inode.  If the generic
+ * inode has the correct field it should be used, and the ZFS code
+ * updated to access the inode.  This can be done incrementally.
+ */
+void
+zfs_inode_update(znode_t *zp)
+{
+	zfsvfs_t	*zfsvfs;
+	struct inode	*inode;
+	uint32_t	blksize;
+	uint64_t	atime[2], mtime[2], ctime[2];
+
+	ASSERT(zp != NULL);
+	zfsvfs = zp->z_zfsvfs;
+	inode = ZTOI(zp);
+
+	sa_lookup(zp->z_sa_hdl, SA_ZPL_ATIME(zfsvfs), &atime, 16);
+	sa_lookup(zp->z_sa_hdl, SA_ZPL_MTIME(zfsvfs), &mtime, 16);
+	sa_lookup(zp->z_sa_hdl, SA_ZPL_CTIME(zfsvfs), &ctime, 16);
+
+	spin_lock(&inode->i_lock);
+	inode->i_generation = zp->z_gen;
+	inode->i_uid = zp->z_uid;
+	inode->i_gid = zp->z_gid;
+	inode->i_nlink = zp->z_links;
+	inode->i_mode = zp->z_mode;
+	inode->i_blkbits = SPA_MINBLOCKSHIFT;
+	dmu_object_size_from_db(sa_get_db(zp->z_sa_hdl), &blksize,
+	    (u_longlong_t *)&inode->i_blocks);
+
+	ZFS_TIME_DECODE(&inode->i_atime, atime);
+	ZFS_TIME_DECODE(&inode->i_mtime, mtime);
+	ZFS_TIME_DECODE(&inode->i_ctime, ctime);
+
+	i_size_write(inode, zp->z_size);
+	spin_unlock(&inode->i_lock);
+}
+
 static uint64_t empty_xattr;
 static uint64_t pad[4];
 static zfs_acl_phys_t acl_phys;
@@ -1534,6 +1575,7 @@ log:
 	zfs_log_truncate(zilog, tx, TX_TRUNCATE, zp, off, len);
 
 	dmu_tx_commit(tx);
+	zfs_inode_update(zp);
 	return (0);
 }