Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 795 insertions, 0 deletions

diff --git a/fs/gfs2/sys.c b/fs/gfs2/sys.c
new file mode 100644
index 000000000..ea2c7b9e4
--- /dev/null
+++ b/fs/gfs2/sys.c
@@ -0,0 +1,795 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
+ * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/sched.h>
+#include <linux/cred.h>
+#include <linux/spinlock.h>
+#include <linux/completion.h>
+#include <linux/buffer_head.h>
+#include <linux/module.h>
+#include <linux/kobject.h>
+#include <linux/uaccess.h>
+#include <linux/gfs2_ondisk.h>
+#include <linux/blkdev.h>
+
+#include "gfs2.h"
+#include "incore.h"
+#include "sys.h"
+#include "super.h"
+#include "glock.h"
+#include "quota.h"
+#include "util.h"
+#include "glops.h"
+#include "recovery.h"
+
+struct gfs2_attr {
+	struct attribute attr;
+	ssize_t (*show)(struct gfs2_sbd *, char *);
+	ssize_t (*store)(struct gfs2_sbd *, const char *, size_t);
+};
+
+static ssize_t gfs2_attr_show(struct kobject *kobj, struct attribute *attr,
+			      char *buf)
+{
+	struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
+	struct gfs2_attr *a = container_of(attr, struct gfs2_attr, attr);
+	return a->show ? a->show(sdp, buf) : 0;
+}
+
+static ssize_t gfs2_attr_store(struct kobject *kobj, struct attribute *attr,
+			       const char *buf, size_t len)
+{
+	struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
+	struct gfs2_attr *a = container_of(attr, struct gfs2_attr, attr);
+	return a->store ? a->store(sdp, buf, len) : len;
+}
+
+static const struct sysfs_ops gfs2_attr_ops = {
+	.show  = gfs2_attr_show,
+	.store = gfs2_attr_store,
+};
+
+
+static struct kset *gfs2_kset;
+
+static ssize_t id_show(struct gfs2_sbd *sdp, char *buf)
+{
+	return sysfs_emit(buf, "%u:%u\n",
+			MAJOR(sdp->sd_vfs->s_dev), MINOR(sdp->sd_vfs->s_dev));
+}
+
+static ssize_t status_show(struct gfs2_sbd *sdp, char *buf)
+{
+	unsigned long f = sdp->sd_flags;
+	ssize_t s;
+
+	s = sysfs_emit(buf,
+		     "Journal Checked:          %d\n"
+		     "Journal Live:             %d\n"
+		     "Journal ID:               %d\n"
+		     "Spectator:                %d\n"
+		     "Withdrawn:                %d\n"
+		     "No barriers:              %d\n"
+		     "No recovery:              %d\n"
+		     "Demote:                   %d\n"
+		     "No Journal ID:            %d\n"
+		     "Mounted RO:               %d\n"
+		     "RO Recovery:              %d\n"
+		     "Force AIL Flush:          %d\n"
+		     "FS Freeze Initiator:      %d\n"
+		     "FS Frozen:                %d\n"
+		     "Killing:                  %d\n"
+		     "sd_log_error:             %d\n"
+		     "sd_log_flush_lock:        %d\n"
+		     "sd_log_num_revoke:        %u\n"
+		     "sd_log_in_flight:         %d\n"
+		     "sd_log_blks_needed:       %d\n"
+		     "sd_log_blks_free:         %d\n"
+		     "sd_log_flush_head:        %d\n"
+		     "sd_log_flush_tail:        %d\n"
+		     "sd_log_blks_reserved:     %d\n"
+		     "sd_log_revokes_available: %d\n"
+		     "sd_log_pinned:            %d\n"
+		     "sd_log_thresh1:           %d\n"
+		     "sd_log_thresh2:           %d\n",
+		     test_bit(SDF_JOURNAL_CHECKED, &f),
+		     test_bit(SDF_JOURNAL_LIVE, &f),
+		     (sdp->sd_jdesc ? sdp->sd_jdesc->jd_jid : 0),
+		     (sdp->sd_args.ar_spectator ? 1 : 0),
+		     test_bit(SDF_WITHDRAWN, &f),
+		     test_bit(SDF_NOBARRIERS, &f),
+		     test_bit(SDF_NORECOVERY, &f),
+		     test_bit(SDF_DEMOTE, &f),
+		     test_bit(SDF_NOJOURNALID, &f),
+		     (sb_rdonly(sdp->sd_vfs) ? 1 : 0),
+		     test_bit(SDF_RORECOVERY, &f),
+		     test_bit(SDF_FORCE_AIL_FLUSH, &f),
+		     test_bit(SDF_FREEZE_INITIATOR, &f),
+		     test_bit(SDF_FROZEN, &f),
+		     test_bit(SDF_KILL, &f),
+		     sdp->sd_log_error,
+		     rwsem_is_locked(&sdp->sd_log_flush_lock),
+		     sdp->sd_log_num_revoke,
+		     atomic_read(&sdp->sd_log_in_flight),
+		     atomic_read(&sdp->sd_log_blks_needed),
+		     atomic_read(&sdp->sd_log_blks_free),
+		     sdp->sd_log_flush_head,
+		     sdp->sd_log_flush_tail,
+		     sdp->sd_log_blks_reserved,
+		     atomic_read(&sdp->sd_log_revokes_available),
+		     atomic_read(&sdp->sd_log_pinned),
+		     atomic_read(&sdp->sd_log_thresh1),
+		     atomic_read(&sdp->sd_log_thresh2));
+	return s;
+}
+
+static ssize_t fsname_show(struct gfs2_sbd *sdp, char *buf)
+{
+	return sysfs_emit(buf, "%s\n", sdp->sd_fsname);
+}
+
+static ssize_t uuid_show(struct gfs2_sbd *sdp, char *buf)
+{
+	struct super_block *s = sdp->sd_vfs;
+
+	buf[0] = '\0';
+	if (uuid_is_null(&s->s_uuid))
+		return 0;
+	return sysfs_emit(buf, "%pUB\n", &s->s_uuid);
+}
+
+static ssize_t freeze_show(struct gfs2_sbd *sdp, char *buf)
+{
+	struct super_block *sb = sdp->sd_vfs;
+	int frozen = (sb->s_writers.frozen == SB_UNFROZEN) ? 0 : 1;
+
+	return sysfs_emit(buf, "%d\n", frozen);
+}
+
+static ssize_t freeze_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
+{
+	int error, n;
+
+	error = kstrtoint(buf, 0, &n);
+	if (error)
+		return error;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	switch (n) {
+	case 0:
+		error = thaw_super(sdp->sd_vfs, FREEZE_HOLDER_USERSPACE, NULL);
+		break;
+	case 1:
+		error = freeze_super(sdp->sd_vfs, FREEZE_HOLDER_USERSPACE, NULL);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (error) {
+		fs_warn(sdp, "freeze %d error %d\n", n, error);
+		return error;
+	}
+
+	return len;
+}
+
+static ssize_t withdraw_show(struct gfs2_sbd *sdp, char *buf)
+{
+	unsigned int b = gfs2_withdrawn(sdp);
+	return sysfs_emit(buf, "%u\n", b);
+}
+
+static ssize_t withdraw_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
+{
+	int error, val;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	error = kstrtoint(buf, 0, &val);
+	if (error)
+		return error;
+
+	if (val != 1)
+		return -EINVAL;
+
+	gfs2_lm(sdp, "withdrawing from cluster at user's request\n");
+	gfs2_withdraw(sdp);
+
+	return len;
+}
+
+static ssize_t statfs_sync_store(struct gfs2_sbd *sdp, const char *buf,
+				 size_t len)
+{
+	int error, val;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	error = kstrtoint(buf, 0, &val);
+	if (error)
+		return error;
+
+	if (val != 1)
+		return -EINVAL;
+
+	gfs2_statfs_sync(sdp->sd_vfs, 0);
+	return len;
+}
+
+static ssize_t quota_sync_store(struct gfs2_sbd *sdp, const char *buf,
+				size_t len)
+{
+	int error, val;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	error = kstrtoint(buf, 0, &val);
+	if (error)
+		return error;
+
+	if (val != 1)
+		return -EINVAL;
+
+	gfs2_quota_sync(sdp->sd_vfs, 0);
+	return len;
+}
+
+static ssize_t quota_refresh_user_store(struct gfs2_sbd *sdp, const char *buf,
+					size_t len)
+{
+	struct kqid qid;
+	int error;
+	u32 id;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	error = kstrtou32(buf, 0, &id);
+	if (error)
+		return error;
+
+	qid = make_kqid(current_user_ns(), USRQUOTA, id);
+	if (!qid_valid(qid))
+		return -EINVAL;
+
+	error = gfs2_quota_refresh(sdp, qid);
+	return error ? error : len;
+}
+
+static ssize_t quota_refresh_group_store(struct gfs2_sbd *sdp, const char *buf,
+					 size_t len)
+{
+	struct kqid qid;
+	int error;
+	u32 id;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	error = kstrtou32(buf, 0, &id);
+	if (error)
+		return error;
+
+	qid = make_kqid(current_user_ns(), GRPQUOTA, id);
+	if (!qid_valid(qid))
+		return -EINVAL;
+
+	error = gfs2_quota_refresh(sdp, qid);
+	return error ? error : len;
+}
+
+static ssize_t demote_rq_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
+{
+	struct gfs2_glock *gl;
+	const struct gfs2_glock_operations *glops;
+	unsigned int glmode;
+	unsigned int gltype;
+	unsigned long long glnum;
+	char mode[16];
+	int rv;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	rv = sscanf(buf, "%u:%llu %15s", &gltype, &glnum,
+		    mode);
+	if (rv != 3)
+		return -EINVAL;
+
+	if (strcmp(mode, "EX") == 0)
+		glmode = LM_ST_UNLOCKED;
+	else if ((strcmp(mode, "CW") == 0) || (strcmp(mode, "DF") == 0))
+		glmode = LM_ST_DEFERRED;
+	else if ((strcmp(mode, "PR") == 0) || (strcmp(mode, "SH") == 0))
+		glmode = LM_ST_SHARED;
+	else
+		return -EINVAL;
+
+	if (gltype > LM_TYPE_JOURNAL)
+		return -EINVAL;
+	if (gltype == LM_TYPE_NONDISK && glnum == GFS2_FREEZE_LOCK)
+		glops = &gfs2_freeze_glops;
+	else
+		glops = gfs2_glops_list[gltype];
+	if (glops == NULL)
+		return -EINVAL;
+	if (!test_and_set_bit(SDF_DEMOTE, &sdp->sd_flags))
+		fs_info(sdp, "demote interface used\n");
+	rv = gfs2_glock_get(sdp, glnum, glops, NO_CREATE, &gl);
+	if (rv)
+		return rv;
+	gfs2_glock_cb(gl, glmode);
+	gfs2_glock_put(gl);
+	return len;
+}
+
+
+#define GFS2_ATTR(name, mode, show, store) \
+static struct gfs2_attr gfs2_attr_##name = __ATTR(name, mode, show, store)
+
+GFS2_ATTR(id,                  0444, id_show,       NULL);
+GFS2_ATTR(fsname,              0444, fsname_show,   NULL);
+GFS2_ATTR(uuid,                0444, uuid_show,     NULL);
+GFS2_ATTR(freeze,              0644, freeze_show,   freeze_store);
+GFS2_ATTR(withdraw,            0644, withdraw_show, withdraw_store);
+GFS2_ATTR(statfs_sync,         0200, NULL,          statfs_sync_store);
+GFS2_ATTR(quota_sync,          0200, NULL,          quota_sync_store);
+GFS2_ATTR(quota_refresh_user,  0200, NULL,          quota_refresh_user_store);
+GFS2_ATTR(quota_refresh_group, 0200, NULL,          quota_refresh_group_store);
+GFS2_ATTR(demote_rq,           0200, NULL,	    demote_rq_store);
+GFS2_ATTR(status,              0400, status_show,   NULL);
+
+static struct attribute *gfs2_attrs[] = {
+	&gfs2_attr_id.attr,
+	&gfs2_attr_fsname.attr,
+	&gfs2_attr_uuid.attr,
+	&gfs2_attr_freeze.attr,
+	&gfs2_attr_withdraw.attr,
+	&gfs2_attr_statfs_sync.attr,
+	&gfs2_attr_quota_sync.attr,
+	&gfs2_attr_quota_refresh_user.attr,
+	&gfs2_attr_quota_refresh_group.attr,
+	&gfs2_attr_demote_rq.attr,
+	&gfs2_attr_status.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(gfs2);
+
+static void gfs2_sbd_release(struct kobject *kobj)
+{
+	struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
+
+	complete(&sdp->sd_kobj_unregister);
+}
+
+static struct kobj_type gfs2_ktype = {
+	.release = gfs2_sbd_release,
+	.default_groups = gfs2_groups,
+	.sysfs_ops     = &gfs2_attr_ops,
+};
+
+
+/*
+ * lock_module. Originally from lock_dlm
+ */
+
+static ssize_t proto_name_show(struct gfs2_sbd *sdp, char *buf)
+{
+	const struct lm_lockops *ops = sdp->sd_lockstruct.ls_ops;
+	return sysfs_emit(buf, "%s\n", ops->lm_proto_name);
+}
+
+static ssize_t block_show(struct gfs2_sbd *sdp, char *buf)
+{
+	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
+	ssize_t ret;
+	int val = 0;
+
+	if (test_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags))
+		val = 1;
+	ret = sysfs_emit(buf, "%d\n", val);
+	return ret;
+}
+
+static ssize_t block_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
+{
+	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
+	int ret, val;
+
+	ret = kstrtoint(buf, 0, &val);
+	if (ret)
+		return ret;
+
+	if (val == 1)
+		set_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags);
+	else if (val == 0) {
+		clear_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags);
+		smp_mb__after_atomic();
+		gfs2_glock_thaw(sdp);
+	} else {
+		return -EINVAL;
+	}
+	return len;
+}
+
+static ssize_t withdraw_helper_status_store(struct gfs2_sbd *sdp,
+					    const char *buf,
+					    size_t len)
+{
+	int ret, val;
+
+	ret = kstrtoint(buf, 0, &val);
+	if (ret)
+		return ret;
+	if (val < 0 || val > 1)
+		return -EINVAL;
+
+	sdp->sd_withdraw_helper_status = val;
+	complete(&sdp->sd_withdraw_helper);
+	return len;
+}
+
+static ssize_t lkfirst_show(struct gfs2_sbd *sdp, char *buf)
+{
+	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
+	return sysfs_emit(buf, "%d\n", ls->ls_first);
+}
+
+static ssize_t lkfirst_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
+{
+	unsigned first;
+	int rv;
+
+	rv = sscanf(buf, "%u", &first);
+	if (rv != 1 || first > 1)
+		return -EINVAL;
+	rv = wait_for_completion_killable(&sdp->sd_locking_init);
+	if (rv)
+		return rv;
+	spin_lock(&sdp->sd_jindex_spin);
+	rv = -EBUSY;
+	if (test_bit(SDF_NOJOURNALID, &sdp->sd_flags) == 0)
+		goto out;
+	rv = -EINVAL;
+	if (sdp->sd_args.ar_spectator)
+		goto out;
+	if (sdp->sd_lockstruct.ls_ops->lm_mount == NULL)
+		goto out;
+	sdp->sd_lockstruct.ls_first = first;
+	rv = 0;
+out:
+        spin_unlock(&sdp->sd_jindex_spin);
+        return rv ? rv : len;
+}
+
+static ssize_t first_done_show(struct gfs2_sbd *sdp, char *buf)
+{
+	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
+	return sysfs_emit(buf, "%d\n", !!test_bit(DFL_FIRST_MOUNT_DONE, &ls->ls_recover_flags));
+}
+
+int gfs2_recover_set(struct gfs2_sbd *sdp, unsigned jid)
+{
+	struct gfs2_jdesc *jd;
+	int rv;
+
+	/* Wait for our primary journal to be initialized */
+	wait_for_completion(&sdp->sd_journal_ready);
+
+	spin_lock(&sdp->sd_jindex_spin);
+	rv = -EBUSY;
+	/**
+	 * If we're a spectator, we use journal0, but it's not really ours.
+	 * So we need to wait for its recovery too. If we skip it we'd never
+	 * queue work to the recovery workqueue, and so its completion would
+	 * never clear the DFL_BLOCK_LOCKS flag, so all our locks would
+	 * permanently stop working.
+	 */
+	if (!sdp->sd_jdesc)
+		goto out;
+	if (sdp->sd_jdesc->jd_jid == jid && !sdp->sd_args.ar_spectator)
+		goto out;
+	rv = -ENOENT;
+	list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
+		if (jd->jd_jid != jid && !sdp->sd_args.ar_spectator)
+			continue;
+		rv = gfs2_recover_journal(jd, false);
+		break;
+	}
+out:
+	spin_unlock(&sdp->sd_jindex_spin);
+	return rv;
+}
+
+static ssize_t recover_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
+{
+	unsigned jid;
+	int rv;
+
+	rv = sscanf(buf, "%u", &jid);
+	if (rv != 1)
+		return -EINVAL;
+
+	if (test_bit(SDF_NORECOVERY, &sdp->sd_flags)) {
+		rv = -ESHUTDOWN;
+		goto out;
+	}
+
+	rv = gfs2_recover_set(sdp, jid);
+out:
+	return rv ? rv : len;
+}
+
+static ssize_t recover_done_show(struct gfs2_sbd *sdp, char *buf)
+{
+	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
+	return sysfs_emit(buf, "%d\n", ls->ls_recover_jid_done);
+}
+
+static ssize_t recover_status_show(struct gfs2_sbd *sdp, char *buf)
+{
+	struct lm_lockstruct *ls = &sdp->sd_lockstruct;
+	return sysfs_emit(buf, "%d\n", ls->ls_recover_jid_status);
+}
+
+static ssize_t jid_show(struct gfs2_sbd *sdp, char *buf)
+{
+	return sysfs_emit(buf, "%d\n", sdp->sd_lockstruct.ls_jid);
+}
+
+static ssize_t jid_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
+{
+        int jid;
+	int rv;
+
+	rv = sscanf(buf, "%d", &jid);
+	if (rv != 1)
+		return -EINVAL;
+	rv = wait_for_completion_killable(&sdp->sd_locking_init);
+	if (rv)
+		return rv;
+	spin_lock(&sdp->sd_jindex_spin);
+	rv = -EINVAL;
+	if (sdp->sd_lockstruct.ls_ops->lm_mount == NULL)
+		goto out;
+	rv = -EBUSY;
+	if (test_bit(SDF_NOJOURNALID, &sdp->sd_flags) == 0)
+		goto out;
+	rv = 0;
+	if (sdp->sd_args.ar_spectator && jid > 0)
+		rv = jid = -EINVAL;
+	sdp->sd_lockstruct.ls_jid = jid;
+	clear_bit(SDF_NOJOURNALID, &sdp->sd_flags);
+	smp_mb__after_atomic();
+	wake_up_bit(&sdp->sd_flags, SDF_NOJOURNALID);
+out:
+	spin_unlock(&sdp->sd_jindex_spin);
+	return rv ? rv : len;
+}
+
+#define GDLM_ATTR(_name,_mode,_show,_store) \
+static struct gfs2_attr gdlm_attr_##_name = __ATTR(_name,_mode,_show,_store)
+
+GDLM_ATTR(proto_name,		0444, proto_name_show,		NULL);
+GDLM_ATTR(block,		0644, block_show,		block_store);
+GDLM_ATTR(withdraw,		0200, NULL,			withdraw_helper_status_store);
+GDLM_ATTR(jid,			0644, jid_show,			jid_store);
+GDLM_ATTR(first,		0644, lkfirst_show,		lkfirst_store);
+GDLM_ATTR(first_done,		0444, first_done_show,		NULL);
+GDLM_ATTR(recover,		0600, NULL,			recover_store);
+GDLM_ATTR(recover_done,		0444, recover_done_show,	NULL);
+GDLM_ATTR(recover_status,	0444, recover_status_show,	NULL);
+
+static struct attribute *lock_module_attrs[] = {
+	&gdlm_attr_proto_name.attr,
+	&gdlm_attr_block.attr,
+	&gdlm_attr_withdraw.attr,
+	&gdlm_attr_jid.attr,
+	&gdlm_attr_first.attr,
+	&gdlm_attr_first_done.attr,
+	&gdlm_attr_recover.attr,
+	&gdlm_attr_recover_done.attr,
+	&gdlm_attr_recover_status.attr,
+	NULL,
+};
+
+/*
+ * get and set struct gfs2_tune fields
+ */
+
+static ssize_t quota_scale_show(struct gfs2_sbd *sdp, char *buf)
+{
+	return sysfs_emit(buf, "%u %u\n",
+			sdp->sd_tune.gt_quota_scale_num,
+			sdp->sd_tune.gt_quota_scale_den);
+}
+
+static ssize_t quota_scale_store(struct gfs2_sbd *sdp, const char *buf,
+				 size_t len)
+{
+	struct gfs2_tune *gt = &sdp->sd_tune;
+	unsigned int x, y;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	if (sscanf(buf, "%u %u", &x, &y) != 2 || !y)
+		return -EINVAL;
+
+	spin_lock(&gt->gt_spin);
+	gt->gt_quota_scale_num = x;
+	gt->gt_quota_scale_den = y;
+	spin_unlock(&gt->gt_spin);
+	return len;
+}
+
+static ssize_t tune_set(struct gfs2_sbd *sdp, unsigned int *field,
+			int check_zero, const char *buf, size_t len)
+{
+	struct gfs2_tune *gt = &sdp->sd_tune;
+	unsigned int x;
+	int error;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	error = kstrtouint(buf, 0, &x);
+	if (error)
+		return error;
+
+	if (check_zero && !x)
+		return -EINVAL;
+
+	spin_lock(&gt->gt_spin);
+	*field = x;
+	spin_unlock(&gt->gt_spin);
+	return len;
+}
+
+#define TUNE_ATTR_3(name, show, store)                                        \
+static struct gfs2_attr tune_attr_##name = __ATTR(name, 0644, show, store)
+
+#define TUNE_ATTR_2(name, store)                                              \
+static ssize_t name##_show(struct gfs2_sbd *sdp, char *buf)                   \
+{                                                                             \
+	return sysfs_emit(buf, "%u\n", sdp->sd_tune.gt_##name);               \
+}                                                                             \
+TUNE_ATTR_3(name, name##_show, store)
+
+#define TUNE_ATTR(name, check_zero)                                           \
+static ssize_t name##_store(struct gfs2_sbd *sdp, const char *buf, size_t len)\
+{                                                                             \
+	return tune_set(sdp, &sdp->sd_tune.gt_##name, check_zero, buf, len);  \
+}                                                                             \
+TUNE_ATTR_2(name, name##_store)
+
+TUNE_ATTR(quota_warn_period, 0);
+TUNE_ATTR(quota_quantum, 0);
+TUNE_ATTR(max_readahead, 0);
+TUNE_ATTR(complain_secs, 0);
+TUNE_ATTR(statfs_slow, 0);
+TUNE_ATTR(new_files_jdata, 0);
+TUNE_ATTR(statfs_quantum, 1);
+TUNE_ATTR_3(quota_scale, quota_scale_show, quota_scale_store);
+TUNE_ATTR(withdraw_helper_timeout, 1);
+
+static struct attribute *tune_attrs[] = {
+	&tune_attr_quota_warn_period.attr,
+	&tune_attr_quota_quantum.attr,
+	&tune_attr_max_readahead.attr,
+	&tune_attr_complain_secs.attr,
+	&tune_attr_statfs_slow.attr,
+	&tune_attr_statfs_quantum.attr,
+	&tune_attr_quota_scale.attr,
+	&tune_attr_new_files_jdata.attr,
+	&tune_attr_withdraw_helper_timeout.attr,
+	NULL,
+};
+
+static const struct attribute_group tune_group = {
+	.name = "tune",
+	.attrs = tune_attrs,
+};
+
+static const struct attribute_group lock_module_group = {
+	.name = "lock_module",
+	.attrs = lock_module_attrs,
+};
+
+int gfs2_sys_fs_add(struct gfs2_sbd *sdp)
+{
+	struct super_block *sb = sdp->sd_vfs;
+	int error;
+	char ro[20];
+	char spectator[20];
+	char *envp[] = { ro, spectator, NULL };
+
+	sprintf(ro, "RDONLY=%d", sb_rdonly(sb));
+	sprintf(spectator, "SPECTATOR=%d", sdp->sd_args.ar_spectator ? 1 : 0);
+
+	init_completion(&sdp->sd_kobj_unregister);
+	sdp->sd_kobj.kset = gfs2_kset;
+	error = kobject_init_and_add(&sdp->sd_kobj, &gfs2_ktype, NULL,
+				     "%s", sdp->sd_table_name);
+	if (error)
+		goto fail_reg;
+
+	error = sysfs_create_group(&sdp->sd_kobj, &tune_group);
+	if (error)
+		goto fail_reg;
+
+	error = sysfs_create_group(&sdp->sd_kobj, &lock_module_group);
+	if (error)
+		goto fail_tune;
+
+	error = sysfs_create_link(&sdp->sd_kobj,
+				  &disk_to_dev(sb->s_bdev->bd_disk)->kobj,
+				  "device");
+	if (error)
+		goto fail_lock_module;
+
+	kobject_uevent_env(&sdp->sd_kobj, KOBJ_ADD, envp);
+	return 0;
+
+fail_lock_module:
+	sysfs_remove_group(&sdp->sd_kobj, &lock_module_group);
+fail_tune:
+	sysfs_remove_group(&sdp->sd_kobj, &tune_group);
+fail_reg:
+	fs_err(sdp, "error %d adding sysfs files\n", error);
+	kobject_put(&sdp->sd_kobj);
+	wait_for_completion(&sdp->sd_kobj_unregister);
+	return error;
+}
+
+void gfs2_sys_fs_del(struct gfs2_sbd *sdp)
+{
+	sysfs_remove_link(&sdp->sd_kobj, "device");
+	sysfs_remove_group(&sdp->sd_kobj, &tune_group);
+	sysfs_remove_group(&sdp->sd_kobj, &lock_module_group);
+	kobject_put(&sdp->sd_kobj);
+	wait_for_completion(&sdp->sd_kobj_unregister);
+}
+
+static int gfs2_uevent(const struct kobject *kobj, struct kobj_uevent_env *env)
+{
+	const struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
+	const struct super_block *s = sdp->sd_vfs;
+
+	add_uevent_var(env, "LOCKTABLE=%s", sdp->sd_table_name);
+	add_uevent_var(env, "LOCKPROTO=%s", sdp->sd_proto_name);
+	if (!test_bit(SDF_NOJOURNALID, &sdp->sd_flags))
+		add_uevent_var(env, "JOURNALID=%d", sdp->sd_lockstruct.ls_jid);
+	if (!uuid_is_null(&s->s_uuid))
+		add_uevent_var(env, "UUID=%pUB", &s->s_uuid);
+	return 0;
+}
+
+static const struct kset_uevent_ops gfs2_uevent_ops = {
+	.uevent = gfs2_uevent,
+};
+
+int gfs2_sys_init(void)
+{
+	gfs2_kset = kset_create_and_add("gfs2", &gfs2_uevent_ops, fs_kobj);
+	if (!gfs2_kset)
+		return -ENOMEM;
+	return 0;
+}
+
+void gfs2_sys_uninit(void)
+{
+	kset_unregister(gfs2_kset);
+}
+