NFS: Expand clone mounts to include other servers

Signed-off-by: Manoj Naik <manoj@almaden.ibm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 64 insertions, 47 deletions

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index db62a5a7e4fc..ebdab885c475 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -1717,14 +1717,13 @@ struct nfs_clone_mount {
 };
 
 static struct super_block *nfs_clone_generic_sb(struct nfs_clone_mount *data,
-                struct super_block *(*clone_client)(struct nfs_server *, struct nfs_clone_mount *))
+                struct super_block *(*fill_sb)(struct nfs_server *, struct nfs_clone_mount *),
+                struct nfs_server *(*fill_server)(struct super_block *, struct nfs_clone_mount *))
 {
         struct nfs_server *server;
         struct nfs_server *parent = NFS_SB(data->sb);
         struct super_block *sb = ERR_PTR(-EINVAL);
         void *err = ERR_PTR(-ENOMEM);
-        struct inode *root_inode;
-        struct nfs_fsinfo fsinfo;
         int len;
 
         server = kmalloc(sizeof(struct nfs_server), GFP_KERNEL);
@@ -1736,53 +1735,17 @@ static struct super_block *nfs_clone_generic_sb(struct nfs_clone_mount *data,
         if (server->hostname == NULL)
                 goto free_server;
         memcpy(server->hostname, parent->hostname, len);
-        server->fsid = data->fattr->fsid;
-        nfs_copy_fh(&server->fh, data->fh);
         if (rpciod_up() != 0)
                 goto free_hostname;
 
-        sb = clone_client(server, data);
+        sb = fill_sb(server, data);
         if (IS_ERR((err = sb)) || sb->s_root)
                 goto kill_rpciod;
 
-        sb->s_op = data->sb->s_op;
-        sb->s_blocksize = data->sb->s_blocksize;
-        sb->s_blocksize_bits = data->sb->s_blocksize_bits;
-        sb->s_maxbytes = data->sb->s_maxbytes;
-
-        server->client_sys = server->client_acl = ERR_PTR(-EINVAL);
-        err = ERR_PTR(-ENOMEM);
-        server->io_stats = nfs_alloc_iostats();
-        if (server->io_stats == NULL)
+        server = fill_server(sb, data);
+        if (IS_ERR((err = server)))
                 goto out_deactivate;
-
-        server->client = rpc_clone_client(parent->client);
-        if (IS_ERR((err = server->client)))
-                goto out_deactivate;
-        if (!IS_ERR(parent->client_sys)) {
-                server->client_sys = rpc_clone_client(parent->client_sys);
-                if (IS_ERR((err = server->client_sys)))
-                        goto out_deactivate;
-        }
-        if (!IS_ERR(parent->client_acl)) {
-                server->client_acl = rpc_clone_client(parent->client_acl);
-                if (IS_ERR((err = server->client_acl)))
-                        goto out_deactivate;
-        }
-        root_inode = nfs_fhget(sb, data->fh, data->fattr);
-        if (!root_inode)
-                goto out_deactivate;
-        sb->s_root = d_alloc_root(root_inode);
-        if (!sb->s_root)
-                goto out_put_root;
-        fsinfo.fattr = data->fattr;
-        if (NFS_PROTO(root_inode)->fsinfo(server, data->fh, &fsinfo) == 0)
-                nfs_super_set_maxbytes(sb, fsinfo.maxfilesize);
-        sb->s_root->d_op = server->rpc_ops->dentry_ops;
-        sb->s_flags |= MS_ACTIVE;
         return sb;
-out_put_root:
-        iput(root_inode);
 out_deactivate:
         up_write(&sb->s_umount);
         deactivate_super(sb);
@@ -1955,21 +1918,73 @@ static struct file_system_type nfs_fs_type = {
         .fs_flags       = FS_ODD_RENAME|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 };
 
-static struct super_block *nfs_clone_client(struct nfs_server *server, struct nfs_clone_mount *data)
+static struct super_block *nfs_clone_sb(struct nfs_server *server, struct nfs_clone_mount *data)
 {
         struct super_block *sb;
 
+        server->fsid = data->fattr->fsid;
+        nfs_copy_fh(&server->fh, data->fh);
         sb = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server);
         if (!IS_ERR(sb) && sb->s_root == NULL && !(server->flags & NFS_MOUNT_NONLM))
                 lockd_up();
         return sb;
 }
 
+static struct nfs_server *nfs_clone_server(struct super_block *sb, struct nfs_clone_mount *data)
+{
+        struct nfs_server *server = NFS_SB(sb);
+        struct nfs_server *parent = NFS_SB(data->sb);
+        struct inode *root_inode;
+        struct nfs_fsinfo fsinfo;
+        void *err = ERR_PTR(-ENOMEM);
+
+        sb->s_op = data->sb->s_op;
+        sb->s_blocksize = data->sb->s_blocksize;
+        sb->s_blocksize_bits = data->sb->s_blocksize_bits;
+        sb->s_maxbytes = data->sb->s_maxbytes;
+
+        server->client_sys = server->client_acl = ERR_PTR(-EINVAL);
+        server->io_stats = nfs_alloc_iostats();
+        if (server->io_stats == NULL)
+                goto out;
+
+        server->client = rpc_clone_client(parent->client);
+        if (IS_ERR((err = server->client)))
+                goto out;
+
+        if (!IS_ERR(parent->client_sys)) {
+                server->client_sys = rpc_clone_client(parent->client_sys);
+                if (IS_ERR((err = server->client_sys)))
+                        goto out;
+        }
+        if (!IS_ERR(parent->client_acl)) {
+                server->client_acl = rpc_clone_client(parent->client_acl);
+                if (IS_ERR((err = server->client_acl)))
+                        goto out;
+        }
+        root_inode = nfs_fhget(sb, data->fh, data->fattr);
+        if (!root_inode)
+                goto out;
+        sb->s_root = d_alloc_root(root_inode);
+        if (!sb->s_root)
+                goto out_put_root;
+        fsinfo.fattr = data->fattr;
+        if (NFS_PROTO(root_inode)->fsinfo(server, data->fh, &fsinfo) == 0)
+                nfs_super_set_maxbytes(sb, fsinfo.maxfilesize);
+        sb->s_root->d_op = server->rpc_ops->dentry_ops;
+        sb->s_flags |= MS_ACTIVE;
+        return server;
+out_put_root:
+        iput(root_inode);
+out:
+        return err;
+}
+
 static struct super_block *nfs_clone_nfs_sb(struct file_system_type *fs_type,
                 int flags, const char *dev_name, void *raw_data)
 {
         struct nfs_clone_mount *data = raw_data;
-        return nfs_clone_generic_sb(data, nfs_clone_client);
+        return nfs_clone_generic_sb(data, nfs_clone_sb, nfs_clone_server);
 }
 
 static struct file_system_type clone_nfs_fs_type = {
@@ -2371,12 +2386,14 @@ static inline char *nfs4_dup_path(const struct dentry *dentry)
         return path;
 }
 
-static struct super_block *nfs4_clone_client(struct nfs_server *server, struct nfs_clone_mount *data)
+static struct super_block *nfs4_clone_sb(struct nfs_server *server, struct nfs_clone_mount *data)
 {
         const struct dentry *dentry = data->dentry;
         struct nfs4_client *clp = server->nfs4_state;
         struct super_block *sb;
 
+        server->fsid = data->fattr->fsid;
+        nfs_copy_fh(&server->fh, data->fh);
         server->mnt_path = nfs4_dup_path(dentry);
         if (IS_ERR(server->mnt_path)) {
                 sb = (struct super_block *)server->mnt_path;
@@ -2403,12 +2420,12 @@ static struct super_block *nfs_clone_nfs4_sb(struct file_system_type *fs_type,
                 int flags, const char *dev_name, void *raw_data)
 {
         struct nfs_clone_mount *data = raw_data;
-        return nfs_clone_generic_sb(data, nfs4_clone_client);
+        return nfs_clone_generic_sb(data, nfs4_clone_sb, nfs_clone_server);
 }
 
 static struct file_system_type clone_nfs4_fs_type = {
         .owner          = THIS_MODULE,
-        .name           = "nfs",
+        .name           = "nfs4",
         .get_sb         = nfs_clone_nfs4_sb,
         .kill_sb        = nfs4_kill_super,
         .fs_flags       = FS_ODD_RENAME|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,