NFS: replace global bl_mount_reply with per-net one

This global variable is used for blocklayout downcall and thus can be corrupted
if case of existence of multiple networks namespaces.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

2 files changed, 5 insertions, 9 deletions

diff --git a/fs/nfs/blocklayout/blocklayout.h b/fs/nfs/blocklayout/blocklayout.h
index 0966b39bbcfb..58ac8614c4c4 100644
--- a/fs/nfs/blocklayout/blocklayout.h
+++ b/fs/nfs/blocklayout/blocklayout.h
@@ -153,11 +153,6 @@ BLK_LSEG2EXT(struct pnfs_layout_segment *lseg)
         return BLK_LO2EXT(lseg->pls_layout);
 }
 
-struct bl_dev_msg {
-        int32_t status;
-        uint32_t major, minor;
-};
-
 struct bl_msg_hdr {
         u8  type;
         u16 totallen; /* length of entire message, including hdr itself */
diff --git a/fs/nfs/blocklayout/blocklayoutdev.c b/fs/nfs/blocklayout/blocklayoutdev.c
index b48f782a94ad..1d58642b1530 100644
--- a/fs/nfs/blocklayout/blocklayoutdev.c
+++ b/fs/nfs/blocklayout/blocklayoutdev.c
@@ -79,15 +79,16 @@ int nfs4_blkdev_put(struct block_device *bdev)
         return blkdev_put(bdev, FMODE_READ);
 }
 
-static struct bl_dev_msg bl_mount_reply;
-
 ssize_t bl_pipe_downcall(struct file *filp, const char __user *src,
                          size_t mlen)
 {
+        struct nfs_net *nn = net_generic(filp->f_dentry->d_sb->s_fs_info,
+                                         nfs_net_id);
+
         if (mlen != sizeof (struct bl_dev_msg))
                 return -EINVAL;
 
-        if (copy_from_user(&bl_mount_reply, src, mlen) != 0)
+        if (copy_from_user(&nn->bl_mount_reply, src, mlen) != 0)
                 return -EFAULT;
 
         wake_up(&bl_wq);
@@ -118,10 +119,10 @@ nfs4_blk_decode_device(struct nfs_server *server,
         };
         uint8_t *dataptr;
         DECLARE_WAITQUEUE(wq, current);
-        struct bl_dev_msg *reply = &bl_mount_reply;
         int offset, len, i, rc;
         struct net *net = server->nfs_client->net;
         struct nfs_net *nn = net_generic(net, nfs_net_id);
+        struct bl_dev_msg *reply = &nn->bl_mount_reply;
 
         dprintk("%s CREATING PIPEFS MESSAGE\n", __func__);
         dprintk("%s: deviceid: %s, mincount: %d\n", __func__, dev->dev_id.data,