[Cluster-devel] GFS2: Pre-pull patch posting (fixes)

[Cluster-devel] GFS2: Pre-pull patch posting (fixes)

[Steven Whitehouse]

Hi,

Out of these fives patches, the one for ensuring that the number of
revokes is not exceeded, and the one for checking the glock is not
already held in gfs2_getxattr are the two most important. The latter
can be triggered by selinux.

The other three patches are very small and fix mostly fairly
trivial issues,

Steve.

[Cluster-devel] [PATCH 1/5] GFS2: Fix typo in gfs2_create_inode()

[Steven Whitehouse]

PTR_RET should be PTR_ERR

Reported-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index bbb2715..a01b8fd 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -594,7 +594,7 @@ static int gfs2_create_inode(struct inode *dir, struct dentry *dentry,
 		}
 		gfs2_glock_dq_uninit(ghs);
 		if (IS_ERR(d))
-			return PTR_RET(d);
+			return PTR_ERR(d);
 		return error;
 	} else if (error != -ENOENT) {
 		goto fail_gunlock;
-- 
1.7.4

[Cluster-devel] [PATCH 2/5] GFS2: WQ_NON_REENTRANT is meaningless and going away

[Steven Whitehouse]

From: Tejun Heo <tj@kernel.org>

dbf2576e37 ("workqueue: make all workqueues non-reentrant") made
WQ_NON_REENTRANT no-op and the flag is going away.  Remove its usages.

This patch doesn't introduce any behavior changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: cluster-devel at redhat.com

diff --git a/fs/gfs2/main.c b/fs/gfs2/main.c
index e04d0e0..7b0f504 100644
--- a/fs/gfs2/main.c
+++ b/fs/gfs2/main.c
@@ -155,7 +155,7 @@ static int __init init_gfs2_fs(void)
 		goto fail_wq;
 
 	gfs2_control_wq = alloc_workqueue("gfs2_control",
-			       WQ_NON_REENTRANT | WQ_UNBOUND | WQ_FREEZABLE, 0);
+					  WQ_UNBOUND | WQ_FREEZABLE, 0);
 	if (!gfs2_control_wq)
 		goto fail_recovery;
 
-- 
1.7.4

[Cluster-devel] [PATCH 3/5] GFS2: don't overrun reserved revokes

[Steven Whitehouse]

From: Benjamin Marzinski <bmarzins@redhat.com>

When run during fsync, a gfs2_log_flush could happen between the
time when gfs2_ail_flush checked the number of blocks to revoke,
and when it actually started the transaction to do those revokes.
This occassionally caused it to need more revokes than it reserved,
causing gfs2 to crash.

Instead of just reserving enough revokes to handle the blocks that
currently need them, this patch makes gfs2_ail_flush reserve the
maximum number of revokes it can, without increasing the total number
of reserved log blocks. This patch also passes the number of reserved
revokes to __gfs2_ail_flush() so that it doesn't go over its limit
and cause a crash like we're seeing. Non-fsync calls to __gfs2_ail_flush
will still cause a BUG() necessary revokes are skipped.

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index 5f2e522..e2e0a90 100644
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -47,7 +47,8 @@ static void gfs2_ail_error(struct gfs2_glock *gl, const struct buffer_head *bh)
  * None of the buffers should be dirty, locked, or pinned.
  */
 
-static void __gfs2_ail_flush(struct gfs2_glock *gl, bool fsync)
+static void __gfs2_ail_flush(struct gfs2_glock *gl, bool fsync,
+			     unsigned int nr_revokes)
 {
 	struct gfs2_sbd *sdp = gl->gl_sbd;
 	struct list_head *head = &gl->gl_ail_list;
@@ -57,7 +58,9 @@ static void __gfs2_ail_flush(struct gfs2_glock *gl, bool fsync)
 
 	gfs2_log_lock(sdp);
 	spin_lock(&sdp->sd_ail_lock);
-	list_for_each_entry_safe(bd, tmp, head, bd_ail_gl_list) {
+	list_for_each_entry_safe_reverse(bd, tmp, head, bd_ail_gl_list) {
+		if (nr_revokes == 0)
+			break;
 		bh = bd->bd_bh;
 		if (bh->b_state & b_state) {
 			if (fsync)
@@ -65,6 +68,7 @@ static void __gfs2_ail_flush(struct gfs2_glock *gl, bool fsync)
 			gfs2_ail_error(gl, bh);
 		}
 		gfs2_trans_add_revoke(sdp, bd);
+		nr_revokes--;
 	}
 	GLOCK_BUG_ON(gl, !fsync && atomic_read(&gl->gl_ail_count));
 	spin_unlock(&sdp->sd_ail_lock);
@@ -91,7 +95,7 @@ static void gfs2_ail_empty_gl(struct gfs2_glock *gl)
 	WARN_ON_ONCE(current->journal_info);
 	current->journal_info = &tr;
 
-	__gfs2_ail_flush(gl, 0);
+	__gfs2_ail_flush(gl, 0, tr.tr_revokes);
 
 	gfs2_trans_end(sdp);
 	gfs2_log_flush(sdp, NULL);
@@ -101,15 +105,19 @@ void gfs2_ail_flush(struct gfs2_glock *gl, bool fsync)
 {
 	struct gfs2_sbd *sdp = gl->gl_sbd;
 	unsigned int revokes = atomic_read(&gl->gl_ail_count);
+	unsigned int max_revokes = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / sizeof(u64);
 	int ret;
 
 	if (!revokes)
 		return;
 
-	ret = gfs2_trans_begin(sdp, 0, revokes);
+	while (revokes > max_revokes)
+		max_revokes += (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header)) / sizeof(u64);
+
+	ret = gfs2_trans_begin(sdp, 0, max_revokes);
 	if (ret)
 		return;
-	__gfs2_ail_flush(gl, fsync);
+	__gfs2_ail_flush(gl, fsync, max_revokes);
 	gfs2_trans_end(sdp);
 	gfs2_log_flush(sdp, NULL);
 }
-- 
1.7.4

[Cluster-devel] [PATCH 4/5] GFS2: alloc_workqueue() doesn't return an ERR_PTR

[Steven Whitehouse]

From: Dan Carpenter <dan.carpenter@oracle.com>

alloc_workqueue() returns a NULL on error, it doesn't return an ERR_PTR.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 9435384..544a809 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -1838,14 +1838,14 @@ int __init gfs2_glock_init(void)
 
 	glock_workqueue = alloc_workqueue("glock_workqueue", WQ_MEM_RECLAIM |
 					  WQ_HIGHPRI | WQ_FREEZABLE, 0);
-	if (IS_ERR(glock_workqueue))
-		return PTR_ERR(glock_workqueue);
+	if (!glock_workqueue)
+		return -ENOMEM;
 	gfs2_delete_workqueue = alloc_workqueue("delete_workqueue",
 						WQ_MEM_RECLAIM | WQ_FREEZABLE,
 						0);
-	if (IS_ERR(gfs2_delete_workqueue)) {
+	if (!gfs2_delete_workqueue) {
 		destroy_workqueue(glock_workqueue);
-		return PTR_ERR(gfs2_delete_workqueue);
+		return -ENOMEM;
 	}
 
 	register_shrinker(&glock_shrinker);
-- 
1.7.4

[Cluster-devel] [PATCH 5/5] GFS2: Check for glock already held in gfs2_getxattr

[Steven Whitehouse]

Since the introduction of atomic_open, gfs2_getxattr can be
called with the glock already held, so we need to allow for
this.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Reported-by: David Teigland <teigland@redhat.com>
Tested-by: David Teigland <teigland@redhat.com>

diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index a01b8fd..64915ee 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -1750,6 +1750,10 @@ static ssize_t gfs2_getxattr(struct dentry *dentry, const char *name,
 	struct gfs2_holder gh;
 	int ret;
 
+	/* For selinux during lookup */
+	if (gfs2_glock_is_locked_by_me(ip->i_gl))
+		return generic_getxattr(dentry, name, data, size);
+
 	gfs2_holder_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
 	ret = gfs2_glock_nq(&gh);
 	if (ret == 0) {
-- 
1.7.4