stat: Pass namespace into phys_stat_resolve_dev, not mnt tree

This makes the API simpler.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

files-reg.c

@@ -351,7 +351,7 @@ static int dump_ghost_remap(char *path, const struct stat *st,
 		return -1;
 	}
 
-	phys_dev = phys_stat_resolve_dev(nsid->mnt.mntinfo_tree, st->st_dev, path);
+	phys_dev = phys_stat_resolve_dev(nsid, st->st_dev, path);
 	list_for_each_entry(gf, &ghost_files, list)
 		if ((gf->dev == phys_dev) && (gf->ino == st->st_ino))
 			goto dump_entry;

include/mount.h

@@ -26,8 +26,7 @@ extern struct mount_info *lookup_mnt_sdev(unsigned int s_dev);
 
 extern struct ns_desc mnt_ns_desc;
 
-extern dev_t phys_stat_resolve_dev(struct mount_info *tree,
-					dev_t st_dev, const char *path);
+extern dev_t phys_stat_resolve_dev(struct ns_id *, dev_t st_dev, const char *path);
 extern bool phys_stat_dev_match(dev_t st_dev, dev_t phys_dev,
 		struct ns_id *, const char *path);
 

mount.c

@@ -192,12 +192,11 @@ static struct mount_info *mount_resolve_path(struct mount_info *mntinfo_tree, co
 	return m;
 }
 
-dev_t phys_stat_resolve_dev(struct mount_info *tree,
-				dev_t st_dev, const char *path)
+dev_t phys_stat_resolve_dev(struct ns_id *ns, dev_t st_dev, const char *path)
 {
 	struct mount_info *m;
 
-	m = mount_resolve_path(tree, path);
+	m = mount_resolve_path(ns->mnt.mntinfo_tree, path);
 	/*
 	 * BTRFS returns subvolume dev-id instead of
 	 * superblock dev-id, in such case return device
@@ -213,7 +212,7 @@ bool phys_stat_dev_match(dev_t st_dev, dev_t phys_dev,
 	if (st_dev == kdev_to_odev(phys_dev))
 		return true;
 
-	return phys_dev == phys_stat_resolve_dev(ns->mnt.mntinfo_tree, st_dev, path);
+	return phys_dev == phys_stat_resolve_dev(ns, st_dev, path);
 }
 
 /*
@@ -580,7 +579,7 @@ static int __open_mountpoint(struct mount_info *pm, int mnt_fd)
 		goto err;
 	}
 
-	dev = phys_stat_resolve_dev(pm->nsid->mnt.mntinfo_tree, st.st_dev, pm->mountpoint + 1);
+	dev = phys_stat_resolve_dev(pm->nsid, st.st_dev, pm->mountpoint + 1);
 	if (dev != pm->s_dev) {
 		pr_err("The file system %#x (%#x) %s %s is inaccessible\n",
 				pm->s_dev, (int)dev, pm->fstype->name, pm->mountpoint);