[PATCH v2] xfs: test attr_list_by_handle cursor iteration

["Darrick J. Wong" <darrick.wong@oracle.com>]

Apparently the XFS attr_list_by_handle ioctl has never actually copied
the cursor contents back to user space, which means that iteration has
never worked.  Add a test case for this and see
"xfs: in _attrlist_by_handle, copy the cursor back to userspace".

v2: Use BULKSTAT_SINGLE for less confusion, fix build errors on RHEL6.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 .gitignore                            |    1 
 src/Makefile                          |    3 -
 src/attr-list-by-handle-cursor-test.c |  185 +++++++++++++++++++++++++++++++++
 tests/xfs/700                         |   64 +++++++++++
 tests/xfs/700.out                     |    5 +
 tests/xfs/group                       |    1 
 6 files changed, 258 insertions(+), 1 deletion(-)
 create mode 100644 src/attr-list-by-handle-cursor-test.c
 create mode 100755 tests/xfs/700
 create mode 100644 tests/xfs/700.out

diff --git a/.gitignore b/.gitignore
index 28bd180..e184a6f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -38,6 +38,7 @@
 /src/alloc
 /src/append_reader
 /src/append_writer
+/src/attr-list-by-handle-cursor-test
 /src/bstat
 /src/bulkstat_unlink_test
 /src/bulkstat_unlink_test_modified
diff --git a/src/Makefile b/src/Makefile
index 1bf318b..ae06d50 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -20,7 +20,8 @@ LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \
 	bulkstat_unlink_test_modified t_dir_offset t_futimens t_immutable \
 	stale_handle pwrite_mmap_blocked t_dir_offset2 seek_sanity_test \
 	seek_copy_test t_readdir_1 t_readdir_2 fsync-tester nsexec cloner \
-	renameat2 t_getcwd e4compact test-nextquota punch-alternating
+	renameat2 t_getcwd e4compact test-nextquota punch-alternating \
+	attr-list-by-handle-cursor-test
 
 SUBDIRS =
 
diff --git a/src/attr-list-by-handle-cursor-test.c b/src/attr-list-by-handle-cursor-test.c
new file mode 100644
index 0000000..ac6ab05
--- /dev/null
+++ b/src/attr-list-by-handle-cursor-test.c
@@ -0,0 +1,185 @@
+/*
+ * Copyright (C) 2016 Oracle.  All Rights Reserved.
+ *
+ * Author: Darrick J. Wong <darrick.wong@oracle.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <attr/attributes.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <stdio.h>
+#include <asm/types.h>
+#include <xfs/xfs.h>
+#include <xfs/handle.h>
+
+#define ATTRBUFSZ		1024
+#define BSTATBUF_NR		32
+
+/* Read all the extended attributes of a file handle. */
+void
+read_handle_xattrs(
+	struct xfs_handle	*handle,
+	int			root_space)
+{
+	struct attrlist_cursor	cur;
+	char			attrbuf[ATTRBUFSZ];
+	char			*firstname = NULL;
+	struct attrlist		*attrlist = (struct attrlist *)attrbuf;
+	struct attrlist_ent	*ent;
+	int			i;
+	int			flags = 0;
+	int			error;
+
+	if (root_space)
+		flags |= ATTR_ROOT;
+
+	memset(&cur, 0, sizeof(cur));
+	while ((error = attr_list_by_handle(handle, sizeof(*handle),
+					    attrbuf, ATTRBUFSZ, flags,
+					    &cur)) == 0) {
+		for (i = 0; i < attrlist->al_count; i++) {
+			ent = ATTR_ENTRY(attrlist, i);
+
+			if (i != 0)
+				continue;
+
+			if (firstname == NULL) {
+				firstname = malloc(ent->a_valuelen);
+				memcpy(firstname, ent->a_name, ent->a_valuelen);
+			} else {
+				if (memcmp(firstname, ent->a_name,
+					   ent->a_valuelen) == 0)
+					fprintf(stderr,
+						"Saw duplicate xattr \"%s\", buggy XFS?\n",
+						ent->a_name);
+				else
+					fprintf(stderr,
+						"Test passes.\n");
+				goto out;
+			}
+		}
+
+		if (!attrlist->al_more)
+			break;
+	}
+
+out:
+	if (firstname)
+		free(firstname);
+	if (error)
+		perror("attr_list_by_handle");
+	return;
+}
+
+/* Iterate a range of inodes. */
+void
+find_inode(
+	struct xfs_handle	*fshandle,
+	int			fd,
+	ino_t			ino)
+{
+	struct xfs_fsop_bulkreq	bulkreq;
+	struct xfs_bstat	*bstatbuf;
+	struct xfs_handle	handle;
+	__u64			first_ino = ino;
+	__s32			buflenout = 0;
+	int			error;
+
+	bstatbuf = malloc(BSTATBUF_NR * sizeof(struct xfs_bstat));
+	if (!bstatbuf) {
+		perror("bulkstat malloc");
+		return;
+	}
+
+	bulkreq.lastip = (__u64 *)&first_ino;
+	bulkreq.icount  = BSTATBUF_NR;
+	bulkreq.ubuffer = (void *)bstatbuf;
+	bulkreq.ocount  = &buflenout;
+
+	memcpy(&handle.ha_fsid, fshandle, sizeof(handle.ha_fsid));
+	handle.ha_fid.fid_len = sizeof(xfs_fid_t) -
+			sizeof(handle.ha_fid.fid_len);
+	handle.ha_fid.fid_pad = 0;
+	error = xfsctl("", fd, XFS_IOC_FSBULKSTAT_SINGLE, &bulkreq);
+	if (error) {
+		perror("bulkstat");
+		goto out;
+	}
+
+	if (buflenout == 0) {
+		fprintf(stderr, "buflenout = 0??\n");
+		goto out;
+	}
+
+	if (bstatbuf->bs_ino != ino) {
+		fprintf(stderr, "Expected ino %llu, got %llu.\n",
+			(unsigned long long)ino, bstatbuf->bs_ino);
+		goto out;
+	}
+
+	handle.ha_fid.fid_gen = bstatbuf->bs_gen;
+	handle.ha_fid.fid_ino = bstatbuf->bs_ino;
+
+	read_handle_xattrs(&handle, false);
+	read_handle_xattrs(&handle, true);
+
+out:
+	free(bstatbuf);
+	return;
+}
+
+int main(
+	int			argc,
+	char			*argv[])
+{
+	struct xfs_handle	*fshandle;
+	size_t			fshandle_len;
+	struct stat		sb;
+	int			fd;
+	int			error;
+
+	if (argc != 2) {
+		fprintf(stderr, "Usage: %s filename\n", argv[0]);
+		return 1;
+	}
+
+	error = path_to_fshandle(argv[1], (void **)&fshandle, &fshandle_len);
+	if (error) {
+		perror("getting fshandle");
+		return 2;
+	}
+
+	fd = open(argv[1], O_RDONLY);
+	if (fd < 0) {
+		perror("opening file");
+		return 2;
+	}
+
+	error = fstat(fd, &sb);
+	if (error) {
+		perror("fstat file");
+		return 2;
+	}
+
+	find_inode(fshandle, fd, sb.st_ino);
+
+	close(fd);
+	free_handle(fshandle, fshandle_len);
+	return 0;
+}
diff --git a/tests/xfs/700 b/tests/xfs/700
new file mode 100755
index 0000000..4a5680d
--- /dev/null
+++ b/tests/xfs/700
@@ -0,0 +1,64 @@
+#! /bin/bash
+# FS QA Test No. 700
+#
+# Check that attr_list_by_handle copies the cursor back to userspace.
+#
+#-----------------------------------------------------------------------
+# Copyright (c) 2016, Oracle and/or its affiliates.  All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it would be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write the Free Software Foundation,
+# Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+#-----------------------------------------------------------------------
+
+seq=`basename "$0"`
+seqres="$RESULT_DIR/$seq"
+echo "QA output created by $seq"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1    # failure is the default!
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+_cleanup()
+{
+	cd /
+	rm -rf "$tmp".* $TEST_DIR/fsmap $TEST_DIR/testout
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+. ./common/attr
+. ./common/populate
+
+# real QA test starts here
+_supported_os Linux
+_require_scratch
+_require_test_program "attr-list-by-handle-cursor-test"
+
+rm -f "$seqres.full"
+
+echo "Format and mount"
+_scratch_mkfs > "$seqres.full" 2>&1
+_scratch_mount
+
+echo "Stuff file with xattrs"
+mkdir $SCRATCH_MNT/foo
+__populate_create_attr $SCRATCH_MNT/foo 100
+
+echo "Run test program"
+./src/attr-list-by-handle-cursor-test $SCRATCH_MNT/foo
+
+# success, all done
+status=0
+exit
diff --git a/tests/xfs/700.out b/tests/xfs/700.out
new file mode 100644
index 0000000..493a68a
--- /dev/null
+++ b/tests/xfs/700.out
@@ -0,0 +1,5 @@
+QA output created by 700
+Format and mount
+Stuff file with xattrs
+Run test program
+Test passes.
diff --git a/tests/xfs/group b/tests/xfs/group
index ff0efa5..b42153d 100644
--- a/tests/xfs/group
+++ b/tests/xfs/group
@@ -307,3 +307,4 @@
 325 auto quick clone
 326 auto quick clone
 327 auto quick clone
+700 auto quick ioctl