[Cluster-devel] [GFS2] Fix problems relating to execution of files on GFS2

[Steven Whitehouse]

Hi,

This patch fixes a couple of problems which affected the execution of files on GFS2.
The first is that there was a corner case where inodes were not always uptodate at
the point at which permissions checks were being carried out, this was resulting in
refusal of execute permission, but only on the first lookup, subsequent requests
worked correctly. The second was a problem relating to incorrect updating of file sizes
which was introduced with the write_begin/end code for GFS2 a little while back.

Signed-off-by: Steven Whitehouse <swhiteho at redhat.com>

diff --git a/fs/gfs2/ops_address.c b/fs/gfs2/ops_address.c
index e16ad81..37406a3 100644
--- a/fs/gfs2/ops_address.c
+++ b/fs/gfs2/ops_address.c
@@ -848,14 +848,11 @@ static int gfs2_write_end(struct file *file, struct address_space *mapping,
 
 	ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
 
-	if (likely(ret >= 0)) {
-		copied = ret;
-		if  ((pos + copied) > inode->i_size) {
-			di = (struct gfs2_dinode *)dibh->b_data;
-			ip->i_di.di_size = inode->i_size;
-			di->di_size = cpu_to_be64(inode->i_size);
-			mark_inode_dirty(inode);
-		}
+	if (likely(ret >= 0) && (inode->i_size > ip->i_di.di_size)) {
+		di = (struct gfs2_dinode *)dibh->b_data;
+		ip->i_di.di_size = inode->i_size;
+		di->di_size = cpu_to_be64(inode->i_size);
+		mark_inode_dirty(inode);
 	}
 
 	if (inode == sdp->sd_rindex)
diff --git a/fs/gfs2/ops_inode.c b/fs/gfs2/ops_inode.c
index 291f0c7..8386ab3 100644
--- a/fs/gfs2/ops_inode.c
+++ b/fs/gfs2/ops_inode.c
@@ -113,8 +113,18 @@ static struct dentry *gfs2_lookup(struct inode *dir, struct dentry *dentry,
 	if (inode && IS_ERR(inode))
 		return ERR_PTR(PTR_ERR(inode));
 
-	if (inode)
+	if (inode) {
+		struct gfs2_glock *gl = GFS2_I(inode)->i_gl;
+		struct gfs2_holder gh;
+		int error;
+		error = gfs2_glock_nq_init(gl, LM_ST_SHARED, LM_FLAG_ANY, &gh);
+		if (error) {
+			iput(inode);
+			return ERR_PTR(error);
+		}
+		gfs2_glock_dq_uninit(&gh);
 		return d_splice_alias(inode, dentry);
+	}
 	d_add(dentry, inode);
 
 	return NULL;