diff options
Diffstat (limited to 'fs/nfs/super.c')
| -rw-r--r-- | fs/nfs/super.c | 43 |
1 files changed, 42 insertions, 1 deletions
diff --git a/fs/nfs/super.c b/fs/nfs/super.c index 1b555cd41e3b..a2b1af89ca1a 100644 --- a/fs/nfs/super.c +++ b/fs/nfs/super.c @@ -1317,7 +1317,9 @@ static int nfs_compare_super(struct super_block *sb, void *data) { struct nfs_server *server = data, *old = NFS_SB(sb); - if (old->nfs_client != server->nfs_client) + if (memcmp(&old->nfs_client->cl_addr, + &server->nfs_client->cl_addr, + sizeof(old->nfs_client->cl_addr)) != 0) return 0; /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */ if (old->flags & NFS_MOUNT_UNSHARED) @@ -1327,6 +1329,39 @@ static int nfs_compare_super(struct super_block *sb, void *data) return 1; } +#define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS) + +static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags) +{ + const struct nfs_server *a = s->s_fs_info; + const struct rpc_clnt *clnt_a = a->client; + const struct rpc_clnt *clnt_b = b->client; + + if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK)) + goto Ebusy; + if (a->nfs_client != b->nfs_client) + goto Ebusy; + if (a->flags != b->flags) + goto Ebusy; + if (a->wsize != b->wsize) + goto Ebusy; + if (a->rsize != b->rsize) + goto Ebusy; + if (a->acregmin != b->acregmin) + goto Ebusy; + if (a->acregmax != b->acregmax) + goto Ebusy; + if (a->acdirmin != b->acdirmin) + goto Ebusy; + if (a->acdirmax != b->acdirmax) + goto Ebusy; + if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor) + goto Ebusy; + return 0; +Ebusy: + return -EBUSY; +} + static int nfs_get_sb(struct file_system_type *fs_type, int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt) { @@ -1361,8 +1396,11 @@ static int nfs_get_sb(struct file_system_type *fs_type, } if (s->s_fs_info != server) { + error = nfs_compare_mount_options(s, server, flags); nfs_free_server(server); server = NULL; + if (error < 0) + goto error_splat_super; } if (!s->s_root) { @@ -1442,8 +1480,11 @@ static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags, } if (s->s_fs_info != server) { + error = nfs_compare_mount_options(s, server, flags); nfs_free_server(server); server = NULL; + if (error < 0) + goto error_splat_super; } if (!s->s_root) { |