1/*
2 * Copyright (c) 2006 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28
29#include <sys/param.h>
30#include <sys/kernel.h>
31#include <sys/proc_internal.h>
32#include <sys/systm.h>
33#include <sys/systm.h>
34#include <sys/mount_internal.h>
35#include <sys/filedesc.h>
36#include <sys/vnode_internal.h>
37#include <sys/imageboot.h>
38
39#include <pexpert/pexpert.h>
40
41extern struct filedesc filedesc0;
42
43extern int (*mountroot)(void);
44extern char rootdevice[];
45
46#define DEBUG_IMAGEBOOT 0
47
48#if DEBUG_IMAGEBOOT
49#define DBG_TRACE(...) printf(__VA_ARGS__)
50#else
51#define DBG_TRACE(...) do {} while(0)
52#endif
53
54extern int di_root_image(const char *path, char devname[], dev_t *dev_p);
55
56#define kIBFilePrefix "file://"
57
58int
59imageboot_needed(void)
60{
61	int result = 0;
62	char *root_path = NULL;
63
64	DBG_TRACE("%s: checking for presence of root path\n", __FUNCTION__);
65
66	MALLOC_ZONE(root_path, caddr_t, MAXPATHLEN, M_NAMEI, M_WAITOK);
67	if (root_path == NULL)
68		panic("%s: M_NAMEI zone exhausted", __FUNCTION__);
69
70	if(PE_parse_boot_argn("rp", root_path, MAXPATHLEN) == TRUE) {
71		/* Got it, now verify scheme */
72
73		if (strncmp(root_path, kIBFilePrefix,
74					strlen(kIBFilePrefix)) == 0) {
75			DBG_TRACE("%s: Found %s\n", __FUNCTION__, root_path);
76			result = 1;
77		} else {
78			DBG_TRACE("%s: Invalid URL scheme for %s\n",
79					__FUNCTION__, root_path);
80		}
81	}
82	FREE_ZONE(root_path, MAXPATHLEN, M_NAMEI);
83
84	return (result);
85}
86
87
88/*
89 * We know there's an image. Attach it, and
90 * switch over to root off it
91 *
92 * NB: p is always kernproc
93 */
94
95int
96imageboot_setup()
97{
98	dev_t       dev;
99	int         error = 0;
100	char *root_path = NULL;
101
102	DBG_TRACE("%s: entry\n", __FUNCTION__);
103
104	MALLOC_ZONE(root_path, caddr_t, MAXPATHLEN, M_NAMEI, M_WAITOK);
105	if (root_path == NULL)
106		return (ENOMEM);
107
108	if(PE_parse_boot_argn("rp", root_path, MAXPATHLEN) == FALSE) {
109		error = ENOENT;
110		goto done;
111	}
112
113	printf("%s: root image url is %s\n", __FUNCTION__, root_path);
114	error = di_root_image(root_path, rootdevice, &dev);
115	if(error) {
116		printf("%s: di_root_image failed: %d\n", __FUNCTION__, error);
117		goto done;
118	}
119
120	rootdev = dev;
121	mountroot = NULL;
122	printf("%s: root device 0x%x\n", __FUNCTION__, rootdev);
123	error = vfs_mountroot();
124
125	if (error == 0 && rootvnode != NULL) {
126		struct vnode *tvp;
127		struct vnode *newdp;
128
129		/*
130		 * Get the vnode for '/'.
131		 * Set fdp->fd_fd.fd_cdir to reference it.
132		 */
133		if (VFS_ROOT(TAILQ_LAST(&mountlist,mntlist), &newdp, vfs_context_kernel()))
134			panic("%s: cannot find root vnode", __FUNCTION__);
135
136		vnode_ref(newdp);
137		vnode_put(newdp);
138		tvp = rootvnode;
139		vnode_rele(tvp);
140		filedesc0.fd_cdir = newdp;
141		rootvnode = newdp;
142		mount_list_lock();
143		TAILQ_REMOVE(&mountlist, TAILQ_FIRST(&mountlist), mnt_list);
144		mount_list_unlock();
145		mountlist.tqh_first->mnt_flag |= MNT_ROOTFS;
146		DBG_TRACE("%s: root switched\n", __FUNCTION__);
147	}
148done:
149	FREE_ZONE(root_path, MAXPATHLEN, M_NAMEI);
150
151	DBG_TRACE("%s: exit\n", __FUNCTION__);
152
153	return (error);
154}
155