xref: /illumos-gate/usr/src/boot/efi/libefi/libefi.c (revision 8119dad84d6416f13557b0ba8e2aaf9064cbcfd3)
1 /*
2  * Copyright (c) 2000 Doug Rabson
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 
29 #include <efi.h>
30 #include <efilib.h>
31 
32 EFI_HANDLE		IH;
33 EFI_SYSTEM_TABLE	*ST;
34 EFI_BOOT_SERVICES	*BS;
35 EFI_RUNTIME_SERVICES	*RS;
36 
37 void *
38 efi_get_table(EFI_GUID *tbl)
39 {
40 	EFI_GUID *id;
41 	int i;
42 
43 	for (i = 0; i < ST->NumberOfTableEntries; i++) {
44 		id = &ST->ConfigurationTable[i].VendorGuid;
45 		if (memcmp(id, tbl, sizeof (EFI_GUID)) == 0)
46 			return (ST->ConfigurationTable[i].VendorTable);
47 	}
48 	return (NULL);
49 }
50 
51 EFI_STATUS
52 OpenProtocolByHandle(EFI_HANDLE handle, EFI_GUID *protocol, void **interface)
53 {
54 	return (BS->OpenProtocol(handle, protocol, interface, IH, NULL,
55 	    EFI_OPEN_PROTOCOL_BY_HANDLE_PROTOCOL));
56 }
57 
58 /*
59  * Allocate memory and query list of handles for indicated protocol.
60  * Returns EFI status, list of handles and number of handles in list.
61  * Caller needs to release the allocated memory.
62  */
63 EFI_STATUS
64 efi_get_protocol_handles(EFI_GUID *protocolguid, uint_t *nhandles,
65     EFI_HANDLE **handlep)
66 {
67 	UINTN bufsz = 0;
68 	EFI_STATUS status;
69 	EFI_HANDLE *handles;
70 
71 	/*
72 	 * get buffer size
73 	 */
74 	*nhandles = 0;
75 	handles = NULL;
76 	status = BS->LocateHandle(ByProtocol, protocolguid,
77 	    NULL, &bufsz, handles);
78 	if (status != EFI_BUFFER_TOO_SMALL)
79 		return (status);
80 
81 	handles = malloc(bufsz);
82 	if (handles == NULL)
83 		return (errno_to_efi_status(ENOMEM));
84 
85 	*nhandles = (uint_t)(bufsz / sizeof (EFI_HANDLE));
86 	/*
87 	 * get handle array
88 	 */
89 	status = BS->LocateHandle(ByProtocol, protocolguid,
90 	    NULL, &bufsz, handles);
91 	if (EFI_ERROR(status)) {
92 		free(handles);
93 		*nhandles = 0;
94 	} else {
95 		*handlep = handles;
96 	}
97 	return (status);
98 }
99