LU-9468 llite: fix for stat under kthread and X86_X32

[fs/lustre-release.git] / lustre / tests / kernel / kinode.c

diff --git a/lustre/tests/kernel/kinode.c b/lustre/tests/kernel/kinode.c
new file mode 100644 (file)
index 0000000..0283c8e
--- /dev/null
+++ b/lustre/tests/kernel/kinode.c
@@ -0,0 +1,169 @@
+/*
+ * GPL HEADER START
+ *
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 only,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will 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 version 2 for more details (a copy is included
+ * in the LICENSE file that accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License
+ * version 2 along with this program; If not, see
+ * http://www.gnu.org/licenses/gpl-2.0.html
+ *
+ * GPL HEADER END
+ */
+
+/*
+ * Copyright 2017 Cray Inc. All rights reserved.
+ * Author: Frank Zago.
+ */
+
+/* Check that the inode number is the same whether the call to
+ * vfs_getattr is coming from a system call or from a kthread. When
+ * CONFIG_X86_X32 was set, the result used to be different for
+ * Lustre. In addition, a user can also check that the same inode
+ * number is also seen from the kernel and userspace.  */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/fs.h>
+#include <linux/version.h>
+
+/* Random ID passed by userspace, and printed in messages, used to
+ * separate different runs of that module. */
+static int run_id;
+module_param(run_id, int, 0644);
+MODULE_PARM_DESC(run_id, "run ID");
+
+/* Name of the file to stat. */
+static char fname[4096];
+module_param_string(fname, fname, sizeof(fname), 0644);
+MODULE_PARM_DESC(fname, "name of file to stat");
+
+struct completion thr_start;
+
+#define PREFIX "lustre_kinode_%u:"
+
+static int stat_file(struct kstat *stbuf)
+{
+       struct file *fd;
+       int rc;
+
+       fd = filp_open(fname, O_RDONLY, 0);
+       if (IS_ERR(fd)) {
+               pr_err(PREFIX " can't open file %s\n", run_id, fname);
+               return -EIO;
+       }
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 9, 0)
+       rc = vfs_getattr(&fd->f_path, stbuf);
+#else
+       rc = vfs_getattr(fd->f_path.mnt, fd->f_path.dentry, stbuf);
+#endif
+       if (rc != 0) {
+               pr_err(PREFIX " vfs_getattr failed: %d\n", run_id, rc);
+               goto out;
+       }
+
+       pr_err(PREFIX " inode is %llu\n", run_id, stbuf->ino);
+       rc = 0;
+
+out:
+       filp_close(fd, NULL);
+
+       return rc;
+}
+
+static int stat_thread(void *data)
+{
+       struct kstat *stbuf = data;
+       int rc;
+
+       /* Signal caller that thread has started. */
+       complete(&thr_start);
+
+       rc = stat_file(stbuf);
+
+       /* Wait for call to kthread_stop. */
+       set_current_state(TASK_INTERRUPTIBLE);
+       while (!kthread_should_stop()) {
+               schedule();
+               set_current_state(TASK_INTERRUPTIBLE);
+       }
+       set_current_state(TASK_RUNNING);
+
+       return rc;
+}
+
+static int __init kinode_init(void)
+{
+       struct task_struct *thr;
+       struct kstat stbuf1;
+       struct kstat stbuf2;
+       int rc;
+
+#ifdef CONFIG_X86_X32
+       pr_err(PREFIX " CONFIG_X86_X32 is set\n", run_id);
+#else
+       pr_err(PREFIX " CONFIG_X86_X32 is not set\n", run_id);
+#endif
+
+       if (strlen(fname) < 1) {
+               pr_err(PREFIX " invalid file name '%s'\n", run_id, fname);
+               goto out;
+       }
+
+       rc = stat_file(&stbuf1);
+       if (rc) {
+               pr_err(PREFIX " direct stat failed: %d\n", run_id, rc);
+               goto out;
+       }
+
+       /* Run the same from a kthread. */
+       init_completion(&thr_start);
+       thr = kthread_run(stat_thread, &stbuf2, "kinode_%u", run_id);
+       if (IS_ERR(thr)) {
+               pr_err(PREFIX " Cannot create kthread\n", run_id);
+               goto out;
+       }
+
+       /* Wait for the thread to start, then wait for it to
+        * terminate. */
+       wait_for_completion(&thr_start);
+       rc = kthread_stop(thr);
+       if (rc) {
+               pr_err(PREFIX " indirect stat failed: %d\n", run_id, rc);
+               goto out;
+       }
+
+       if (stbuf1.ino != stbuf2.ino)
+               pr_err(PREFIX " inode numbers are different: %llu %llu\n",
+                      run_id, stbuf1.ino, stbuf2.ino);
+       else
+               pr_err(PREFIX " inode numbers are identical: %llu\n",
+                      run_id, stbuf1.ino);
+
+out:
+       /* Don't load. */
+       return -EINVAL;
+}
+
+static void __exit kinode_exit(void)
+{
+}
+
+MODULE_AUTHOR("OpenSFS, Inc. <http://www.lustre.org/>");
+MODULE_DESCRIPTION("Lustre inode stat test module");
+MODULE_VERSION(LUSTRE_VERSION_STRING);
+MODULE_LICENSE("GPL");
+
+module_init(kinode_init);
+module_exit(kinode_exit);