NFS: Fix a spinlock recursion inside nfs_update_inode()
In cases where the server has gone insane, nfs_update_inode() may end
up calling nfs_invalidate_inode(), which again calls stuff that takes
the inode->i_lock that we're already holding.
In addition, given the sort of things we have in NFS these days that
need to be cleaned up on inode release, I'm not sure we should ever
be calling make_bad_inode().
Fix up spinlock recursion, and limit nfs_invalidate_inode() to clearing
the caches, and marking the inode as being stale.
Thanks to Steve Dickson <SteveD@redhat.com> for spotting this.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 6391d89..aaab1a5 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -643,14 +643,11 @@
/*
* Invalidate the local caches
*/
-void
-nfs_zap_caches(struct inode *inode)
+static void nfs_zap_caches_locked(struct inode *inode)
{
struct nfs_inode *nfsi = NFS_I(inode);
int mode = inode->i_mode;
- spin_lock(&inode->i_lock);
-
NFS_ATTRTIMEO(inode) = NFS_MINATTRTIMEO(inode);
NFS_ATTRTIMEO_UPDATE(inode) = jiffies;
@@ -659,7 +656,12 @@
nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL|NFS_INO_REVAL_PAGECACHE;
else
nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL|NFS_INO_REVAL_PAGECACHE;
+}
+void nfs_zap_caches(struct inode *inode)
+{
+ spin_lock(&inode->i_lock);
+ nfs_zap_caches_locked(inode);
spin_unlock(&inode->i_lock);
}
@@ -676,16 +678,13 @@
}
/*
- * Invalidate, but do not unhash, the inode
+ * Invalidate, but do not unhash, the inode.
+ * NB: must be called with inode->i_lock held!
*/
-static void
-nfs_invalidate_inode(struct inode *inode)
+static void nfs_invalidate_inode(struct inode *inode)
{
- umode_t save_mode = inode->i_mode;
-
- make_bad_inode(inode);
- inode->i_mode = save_mode;
- nfs_zap_caches(inode);
+ set_bit(NFS_INO_STALE, &NFS_FLAGS(inode));
+ nfs_zap_caches_locked(inode);
}
struct nfs_find_desc {
@@ -1528,14 +1527,13 @@
printk(KERN_DEBUG "%s: inode %ld mode changed, %07o to %07o\n",
__FUNCTION__, inode->i_ino, inode->i_mode, fattr->mode);
#endif
+ out_err:
/*
* No need to worry about unhashing the dentry, as the
* lookup validation will know that the inode is bad.
* (But we fall through to invalidate the caches.)
*/
nfs_invalidate_inode(inode);
- out_err:
- set_bit(NFS_INO_STALE, &NFS_FLAGS(inode));
return -ESTALE;
}