>From 24d9765fc18c7838ccdbb0d71fb706321d9b824c Mon Sep 17 00:00:00 2001
From: Steven Whitehouse <swhiteho@redhat.com>
Date: Tue, 18 Jan 2011 14:49:08 +0000
Subject: GFS2: Fix error path in gfs2_lookup_by_inum()

In the (impossible, except if there is fs corruption) error path
in gfs2_lookup_by_inum() if the call to gfs2_inode_refresh()
fails, it was leaving the function by calling iput() rather
than iget_failed(). This would cause future lookups of the same
inode to block forever.

This patch fixes the problem by moving the call to gfs2_inode_refresh()
into gfs2_inode_lookup() where iget_failed() is part of the error path
already. Also this cleans up some unreachable code and makes
gfs2_set_iop() static.

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

diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index 2232b3c..7aa7d4f 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -74,16 +74,14 @@ static struct inode *gfs2_iget(struct super_block *sb, u64 no_addr)
}

/**
- * GFS2 lookup code fills in vfs inode contents based on info obtained
- * from directory entry inside gfs2_inode_lookup(). This has caused issues
- * with NFS code path since its get_dentry routine doesn't have the relevant
- * directory entry when gfs2_inode_lookup() is invoked. Part of the code
- * segment inside gfs2_inode_lookup code needs to get moved around.
+ * gfs2_set_iop - Sets inode operations
+ * @inode: The inode with correct i_mode filled in
*
- * Clears I_NEW as well.
- **/
+ * GFS2 lookup code fills in vfs inode contents based on info obtained
+ * from directory entry inside gfs2_inode_lookup().
+ */

-void gfs2_set_iop(struct inode *inode)
+static void gfs2_set_iop(struct inode *inode)
{
struct gfs2_sbd *sdp = GFS2_SB(inode);
umode_t mode = inode->i_mode;
@@ -106,8 +104,6 @@ void gfs2_set_iop(struct inode *inode)
inode->i_op = &gfs2_file_iops;
init_special_inode(inode, inode->i_mode, inode->i_rdev);
}
-
- unlock_new_inode(inode);
}

/**
@@ -119,10 +115,8 @@ void gfs2_set_iop(struct inode *inode)
* 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)
+struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type,
+ u64 no_addr, u64 no_formal_ino)
{
struct inode *inode;
struct gfs2_inode *ip;
@@ -152,51 +146,37 @@ struct inode *gfs2_inode_lookup(struct super_block *sb,
error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh);
if (unlikely(error))
goto fail_iopen;
- ip->i_iopen_gh.gh_gl->gl_object = ip;

+ ip->i_iopen_gh.gh_gl->gl_object = ip;
gfs2_glock_put(io_gl);
io_gl = NULL;

- if ((type == DT_UNKNOWN) && (no_formal_ino == 0))
- goto gfs2_nfsbypass;
-
- inode->i_mode = DT2IF(type);
-
- /*
- * We must read the inode in order to work out its type in
- * this case. Note that this doesn't happen often as we normally
- * know the type beforehand. This code path only occurs during
- * unlinked inode recovery (where it is safe to do this glock,
- * which is not true in the general case).
- */
if (type == DT_UNKNOWN) {
- struct gfs2_holder gh;
- error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
- if (unlikely(error))
- goto fail_glock;
- /* Inode is now uptodate */
- gfs2_glock_dq_uninit(&gh);
+ /* Inode glock must be locked already */
+ error = gfs2_inode_refresh(GFS2_I(inode));
+ if (error)
+ goto fail_refresh;
+ } else {
+ inode->i_mode = DT2IF(type);
}

gfs2_set_iop(inode);
+ unlock_new_inode(inode);
}

-gfs2_nfsbypass:
return inode;
-fail_glock:
- gfs2_glock_dq(&ip->i_iopen_gh);
+
+fail_refresh:
+ ip->i_iopen_gh.gh_gl->gl_object = NULL;
+ gfs2_glock_dq_uninit(&ip->i_iopen_gh);
fail_iopen:
if (io_gl)
gfs2_glock_put(io_gl);
fail_put:
- if (inode->i_state & I_NEW)
- ip->i_gl->gl_object = NULL;
+ ip->i_gl->gl_object = NULL;
gfs2_glock_put(ip->i_gl);
fail:
- if (inode->i_state & I_NEW)
- iget_failed(inode);
- else
- iput(inode);
+ iget_failed(inode);
return ERR_PTR(error);
}

@@ -221,14 +201,6 @@ struct inode *gfs2_lookup_by_inum(struct gfs2_sbd *sdp, u64 no_addr,
if (IS_ERR(inode))
goto fail;

- error = gfs2_inode_refresh(GFS2_I(inode));
- if (error)
- goto fail_iput;
-
- /* Pick up the works we bypass in gfs2_inode_lookup */
- if (inode->i_state & I_NEW)
- gfs2_set_iop(inode);
-
/* Two extra checks for NFS only */
if (no_formal_ino) {
error = -ESTALE;
diff --git a/fs/gfs2/inode.h b/fs/gfs2/inode.h
index 732a183..3e00a66 100644
--- a/fs/gfs2/inode.h
+++ b/fs/gfs2/inode.h
@@ -96,7 +96,6 @@ err:
return -EIO;
}

-extern void gfs2_set_iop(struct inode *inode);
extern struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned type,
u64 no_addr, u64 no_formal_ino);
extern struct inode *gfs2_lookup_by_inum(struct gfs2_sbd *sdp, u64 no_addr,
--
1.7.3.3