vfs: new superblock methods to override /proc/*/mount{s,info}
a) ->show_devname(m, mnt) - what to put into devname columns in mounts,
mountinfo and mountstats
b) ->show_path(m, mnt) - what to put into relative path column in mountinfo
Leaving those NULL gives old behaviour. NFS switched to using those.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index a6ab483..79bc61f 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -263,6 +263,8 @@
static void nfs_umount_begin(struct super_block *);
static int nfs_statfs(struct dentry *, struct kstatfs *);
static int nfs_show_options(struct seq_file *, struct vfsmount *);
+static int nfs_show_devname(struct seq_file *, struct vfsmount *);
+static int nfs_show_path(struct seq_file *, struct vfsmount *);
static int nfs_show_stats(struct seq_file *, struct vfsmount *);
static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
@@ -296,6 +298,8 @@
.evict_inode = nfs_evict_inode,
.umount_begin = nfs_umount_begin,
.show_options = nfs_show_options,
+ .show_devname = nfs_show_devname,
+ .show_path = nfs_show_path,
.show_stats = nfs_show_stats,
.remount_fs = nfs_remount,
};
@@ -366,6 +370,8 @@
.evict_inode = nfs4_evict_inode,
.umount_begin = nfs_umount_begin,
.show_options = nfs_show_options,
+ .show_devname = nfs_show_devname,
+ .show_path = nfs_show_path,
.show_stats = nfs_show_stats,
.remount_fs = nfs_remount,
};
@@ -726,6 +732,28 @@
return 0;
}
+static int nfs_show_devname(struct seq_file *m, struct vfsmount *mnt)
+{
+ char *page = (char *) __get_free_page(GFP_KERNEL);
+ char *devname, *dummy;
+ int err = 0;
+ if (!page)
+ return -ENOMEM;
+ devname = nfs_path(&dummy, mnt->mnt_root, page, PAGE_SIZE);
+ if (IS_ERR(devname))
+ err = PTR_ERR(devname);
+ else
+ seq_escape(m, devname, " \t\n\\");
+ free_page((unsigned long)page);
+ return err;
+}
+
+static int nfs_show_path(struct seq_file *m, struct vfsmount *mnt)
+{
+ seq_puts(m, "/");
+ return 0;
+}
+
/*
* Present statistical information for this VFS mountpoint
*/