[PATCH 1/3] [GFS2] filesystem consistency error from do_strip

swhiteho
2008-05-20T10:01:15Z

From: Bob Peterson <rpeterso@redhat.com>

This patch fixes a GFS2 filesystem consistency error reported from
function do_strip. The problem was caused by a timing window
that allowed two vfs inodes to be created in memory that point
to the same file. The problem is fixed by making the vfs's
iget_test, iget_set mechanism check and set a new bit in the
in-core gfs2_inode structure while the vfs inode spin_lock is held.

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

diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index d31bada..07d84d1 100644
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -249,7 +249,7 @@ static int inode_go_lock(struct gfs2_holder *gh)
struct gfs2_inode *ip = gl->gl_object;
int error = 0;

- if (!ip)
+ if (!ip || (gh->gh_flags & GL_SKIP))
return 0;

if (test_bit(GIF_INVALID, &ip->i_flags)) {
diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h
index 9c2c0b9..eabe5ea 100644
--- a/fs/gfs2/incore.h
+++ b/fs/gfs2/incore.h
@@ -236,6 +236,7 @@ enum {
GIF_INVALID = 0,
GIF_QD_LOCKED = 1,
GIF_SW_PAGED = 3,
+ GIF_USER = 4, /* user inode, not metadata addr space */
};

struct gfs2_dinode_host {
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index 3a9ef52..09453d0 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -47,8 +47,7 @@ static int iget_test(struct inode *inode, void *opaque)
struct gfs2_inode *ip = GFS2_I(inode);
u64 *no_addr = opaque;

- if (ip->i_no_addr == *no_addr &&
- inode->i_private != NULL)
+ if (ip->i_no_addr == *no_addr && test_bit(GIF_USER, &ip->i_flags))
return 1;

return 0;
@@ -61,6 +60,7 @@ static int iget_set(struct inode *inode, void *opaque)

inode->i_ino = (unsigned long)*no_addr;
ip->i_no_addr = *no_addr;
+ set_bit(GIF_USER, &ip->i_flags);
return 0;
}

@@ -86,7 +86,7 @@ static int iget_skip_test(struct inode *inode, void *opaque)
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_skip_data *data = opaque;

- if (ip->i_no_addr == data->no_addr && inode->i_private != NULL){
+ if (ip->i_no_addr == data->no_addr && test_bit(GIF_USER, &ip->i_flags)){
if (inode->i_state & (I_FREEING|I_CLEAR|I_WILL_FREE)){
data->skipped = 1;
return 0;
@@ -105,6 +105,7 @@ static int iget_skip_set(struct inode *inode, void *opaque)
return 1;
inode->i_ino = (unsigned long)(data->no_addr);
ip->i_no_addr = data->no_addr;
+ set_bit(GIF_USER, &ip->i_flags);
return 0;
}

@@ -166,7 +167,7 @@ void gfs2_set_iop(struct inode *inode)
* Returns: A VFS inode, or an error
*/

-struct inode *gfs2_inode_lookup(struct super_block *sb,
+struct inode *gfs2_inode_lookup(struct super_block *sb,
unsigned int type,
u64 no_addr,
u64 no_formal_ino, int skip_freeing)
@@ -187,7 +188,6 @@ struct inode *gfs2_inode_lookup(struct super_block *sb,

if (inode->i_state & I_NEW) {
struct gfs2_sbd *sdp = GFS2_SB(inode);
- inode->i_private = ip;
ip->i_no_formal_ino = no_formal_ino;

error = gfs2_glock_get(sdp, no_addr, &gfs2_inode_glops, CREATE, &ip->i_gl);
diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c
index 85aea27..78d75f8 100644
--- a/fs/gfs2/meta_io.c
+++ b/fs/gfs2/meta_io.c
@@ -1,6 +1,6 @@
/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
- * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
@@ -69,13 +69,15 @@ static const struct address_space_operations aspace_aops = {
struct inode *gfs2_aspace_get(struct gfs2_sbd *sdp)
{
struct inode *aspace;
+ struct gfs2_inode *ip;

aspace = new_inode(sdp->sd_vfs);
if (aspace) {
mapping_set_gfp_mask(aspace->i_mapping, GFP_NOFS);
aspace->i_mapping->a_ops = &aspace_aops;
aspace->i_size = ~0ULL;
- aspace->i_private = NULL;
+ ip = GFS2_I(aspace);
+ clear_bit(GIF_USER, &ip->i_flags);
insert_inode_hash(aspace);
}
return aspace;
diff --git a/fs/gfs2/ops_super.c b/fs/gfs2/ops_super.c
index 2278c68..0b7cc92 100644
--- a/fs/gfs2/ops_super.c
+++ b/fs/gfs2/ops_super.c
@@ -1,6 +1,6 @@
/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
- * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
+ * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
@@ -52,7 +52,7 @@ static int gfs2_write_inode(struct inode *inode, int sync)
struct gfs2_inode *ip = GFS2_I(inode);

/* Check this is a "normal" inode */
- if (inode->i_private) {
+ if (test_bit(GIF_USER, &ip->i_flags)) {
if (current->flags & PF_MEMALLOC)
return 0;
if (sync)
@@ -297,8 +297,9 @@ static int gfs2_remount_fs(struct super_block *sb, int *flags, char *data)
*/
static void gfs2_drop_inode(struct inode *inode)
{
- if (inode->i_private && inode->i_nlink) {
- struct gfs2_inode *ip = GFS2_I(inode);
+ struct gfs2_inode *ip = GFS2_I(inode);
+
+ if (test_bit(GIF_USER, &ip->i_flags) && inode->i_nlink) {
struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
if (gl && test_bit(GLF_DEMOTE, &gl->gl_flags))
clear_nlink(inode);
@@ -314,12 +315,13 @@ static void gfs2_drop_inode(struct inode *inode)

static void gfs2_clear_inode(struct inode *inode)
{
+ struct gfs2_inode *ip = GFS2_I(inode);
+
/* This tells us its a "real" inode and not one which only
* serves to contain an address space (see rgrp.c, meta_io.c)
* which therefore doesn't have its own glocks.
*/
- if (inode->i_private) {
- struct gfs2_inode *ip = GFS2_I(inode);
+ if (test_bit(GIF_USER, &ip->i_flags)) {
ip->i_gl->gl_object = NULL;
gfs2_glock_schedule_for_reclaim(ip->i_gl);
gfs2_glock_put(ip->i_gl);
@@ -419,7 +421,7 @@ static void gfs2_delete_inode(struct inode *inode)
struct gfs2_holder gh;
int error;

- if (!inode->i_private)
+ if (!test_bit(GIF_USER, &ip->i_flags))
goto out;

error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
--
1.5.1.2