[Cluster-devel] [PATCH 4/4] GFS2: Make deletes use regular inode_lookup with special code path

[Bob Peterson <rpeterso@redhat.com>]

This patch changes the inode reclaiming code, delete_work_func, use
the normal gfs2_inode_lookup, but with a special parameter, for_del
which causes additional checks to be made.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
---
 fs/gfs2/dir.c        |  2 +-
 fs/gfs2/glock.c      |  9 +--------
 fs/gfs2/inode.c      | 32 ++++++++++++++++++++++++++++----
 fs/gfs2/inode.h      |  3 ++-
 fs/gfs2/ops_fstype.c |  2 +-
 5 files changed, 33 insertions(+), 15 deletions(-)

diff --git a/fs/gfs2/dir.c b/fs/gfs2/dir.c
index 2bef023..6a92592 100644
--- a/fs/gfs2/dir.c
+++ b/fs/gfs2/dir.c
@@ -1660,7 +1660,7 @@ struct inode *gfs2_dir_search(struct inode *dir, const struct qstr *name,
 		brelse(bh);
 		if (fail_on_exist)
 			return ERR_PTR(-EEXIST);
-		inode = gfs2_inode_lookup(dir->i_sb, dtype, addr, formal_ino);
+		inode = gfs2_inode_lookup(dir->i_sb, dtype, addr, formal_ino, 0);
 		if (!IS_ERR(inode))
 			GFS2_I(inode)->i_rahead = rahead;
 		return inode;
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index 3e16d82..795c2f3 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -568,7 +568,6 @@ static void delete_work_func(struct work_struct *work)
 {
 	struct gfs2_glock *gl = container_of(work, struct gfs2_glock, gl_delete);
 	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
-	struct gfs2_inode *ip;
 	struct inode *inode;
 	u64 no_addr = gl->gl_name.ln_number;
 
@@ -578,13 +577,7 @@ static void delete_work_func(struct work_struct *work)
 	if (test_bit(GLF_INODE_CREATING, &gl->gl_flags))
 		goto out;
 
-	ip = gl->gl_object;
-	/* Note: Unsafe to dereference ip as we don't hold right refs/locks */
-
-	if (ip)
-		inode = gfs2_ilookup(sdp->sd_vfs, no_addr);
-	else
-		inode = gfs2_lookup_by_inum(sdp, no_addr, NULL, GFS2_BLKST_UNLINKED);
+	inode = gfs2_inode_lookup(sdp->sd_vfs, DT_UNKNOWN, no_addr, 0, 1);
 	if (inode && !IS_ERR(inode)) {
 		d_prune_aliases(inode);
 		iput(inode);
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index 01b6d1a..0357862 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -75,17 +75,37 @@ static void gfs2_set_iop(struct inode *inode)
 	}
 }
 
+static int verify_unlinked(struct gfs2_inode *ip)
+{
+	struct gfs2_holder i_gh;
+	struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
+	int error;
+
+	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, &i_gh);
+	if (error)
+		return error;
+
+	error = gfs2_check_blk_type(sdp, ip->i_no_addr, GFS2_BLKST_UNLINKED);
+	if (error == 0)
+		error = gfs2_inode_refresh(ip);
+
+	gfs2_glock_dq_uninit(&i_gh);
+	return error;
+}
+
 /**
  * gfs2_inode_lookup - Lookup an inode
  * @sb: The super block
- * @no_addr: The inode number
  * @type: The type of the inode
+ * @no_addr: The inode number
+ * @no_formal_ino: The formal inode number
+ * @for_del: Is this lookup for deleting purposes?
  *
  * Returns: A VFS inode, or an error
  */
 
 struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type,
-				u64 no_addr, u64 no_formal_ino)
+				u64 no_addr, u64 no_formal_ino, int for_del)
 {
 	struct inode *inode;
 	struct gfs2_inode *ip;
@@ -121,7 +141,11 @@ struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type,
 		gfs2_glock_put(io_gl);
 		io_gl = NULL;
 
-		if (type == DT_UNKNOWN) {
+		if (for_del) {
+			error = verify_unlinked(ip);
+			if (error)
+				goto fail_refresh;
+		} else if (type == DT_UNKNOWN) {
 			/* Inode glock must be locked already */
 			error = gfs2_inode_refresh(GFS2_I(inode));
 			if (error)
@@ -169,7 +193,7 @@ struct inode *gfs2_lookup_by_inum(struct gfs2_sbd *sdp, u64 no_addr,
 	if (error)
 		goto fail;
 
-	inode = gfs2_inode_lookup(sb, DT_UNKNOWN, no_addr, 0);
+	inode = gfs2_inode_lookup(sb, DT_UNKNOWN, no_addr, 0, 0);
 	if (IS_ERR(inode))
 		goto fail;
 
diff --git a/fs/gfs2/inode.h b/fs/gfs2/inode.h
index e1af0d4..d6233e9 100644
--- a/fs/gfs2/inode.h
+++ b/fs/gfs2/inode.h
@@ -94,7 +94,8 @@ err:
 }
 
 extern struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned type, 
-				       u64 no_addr, u64 no_formal_ino);
+				       u64 no_addr, u64 no_formal_ino,
+				       int for_del);
 extern struct inode *gfs2_lookup_by_inum(struct gfs2_sbd *sdp, u64 no_addr,
 					 u64 *no_formal_ino,
 					 unsigned int blktype);
diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c
index 9ed522c..7aacdf2 100644
--- a/fs/gfs2/ops_fstype.c
+++ b/fs/gfs2/ops_fstype.c
@@ -454,7 +454,7 @@ static int gfs2_lookup_root(struct super_block *sb, struct dentry **dptr,
 	struct dentry *dentry;
 	struct inode *inode;
 
-	inode = gfs2_inode_lookup(sb, DT_DIR, no_addr, 0);
+	inode = gfs2_inode_lookup(sb, DT_DIR, no_addr, 0, 0);
 	if (IS_ERR(inode)) {
 		fs_err(sdp, "can't read in %s inode: %ld\n", name, PTR_ERR(inode));
 		return PTR_ERR(inode);
-- 
2.5.0