xref: /illumos-gate/usr/src/uts/i86pc/os/smb_dev.c (revision 8119dad84d6416f13557b0ba8e2aaf9064cbcfd3)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 
23 /*
24  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
25  * Use is subject to license terms.
26  * Copyright (c) 2018, Joyent, Inc.
27  */
28 
29 /*
30  * Platform-Specific SMBIOS Subroutines
31  *
32  * The routines in this file form part of <sys/smbios_impl.h> and combine with
33  * the usr/src/common/smbios code to form an in-kernel SMBIOS decoding service.
34  * The SMBIOS entry point is locating by scanning a range of physical memory
35  * assigned to BIOS as described in Section 2 of the DMTF SMBIOS specification.
36  */
37 
38 #include <sys/smbios_impl.h>
39 #include <sys/sysmacros.h>
40 #include <sys/errno.h>
41 #include <sys/psm.h>
42 #include <sys/smp_impldefs.h>
43 
44 smbios_hdl_t *ksmbios;
45 int ksmbios_flags;
46 
47 smbios_hdl_t *
48 smb_open_error(smbios_hdl_t *shp, int *errp, int err)
49 {
50 	if (shp != NULL)
51 		smbios_close(shp);
52 
53 	if (errp != NULL)
54 		*errp = err;
55 
56 	if (ksmbios == NULL)
57 		cmn_err(CE_CONT, "?SMBIOS not loaded (%s)", smbios_errmsg(err));
58 
59 	return (NULL);
60 }
61 
62 smbios_hdl_t *
63 smbios_open(const char *file, int version, int flags, int *errp)
64 {
65 	smbios_hdl_t *shp = NULL;
66 	smbios_entry_t *ep;
67 	caddr_t stbuf, bios, p, q;
68 	caddr_t smb2, smb3;
69 	uint64_t startaddr, startoff = 0;
70 	size_t bioslen;
71 	uint_t smbe_stlen;
72 	smbios_entry_point_t ep_type;
73 	uint8_t smbe_major, smbe_minor;
74 	int err;
75 
76 	if (file != NULL || (flags & ~SMB_O_MASK))
77 		return (smb_open_error(shp, errp, ESMB_INVAL));
78 
79 	if ((startaddr = ddi_prop_get_int64(DDI_DEV_T_ANY, ddi_root_node(),
80 	    DDI_PROP_DONTPASS, "smbios-address", 0)) == 0) {
81 		startaddr = SMB_RANGE_START;
82 		bioslen = SMB_RANGE_LIMIT - SMB_RANGE_START + 1;
83 	} else {
84 		/* We have smbios address from boot loader, map one page. */
85 		bioslen = MMU_PAGESIZE;
86 		startoff = startaddr & MMU_PAGEOFFSET;
87 		startaddr &= MMU_PAGEMASK;
88 	}
89 
90 	bios = psm_map_phys(startaddr, bioslen, PSM_PROT_READ);
91 
92 	if (bios == NULL)
93 		return (smb_open_error(shp, errp, ESMB_MAPDEV));
94 
95 	/*
96 	 * In case we did map one page, make sure we will not cross
97 	 * the end of the page.
98 	 */
99 	p = bios + startoff;
100 	q = bios + bioslen - startoff;
101 	smb2 = smb3 = NULL;
102 	while (p < q) {
103 		if (smb2 != NULL && smb3 != NULL)
104 			break;
105 
106 		if (smb3 == NULL && strncmp(p, SMB3_ENTRY_EANCHOR,
107 		    SMB3_ENTRY_EANCHORLEN) == 0) {
108 			smb3 = p;
109 		} else if (smb2 == NULL && strncmp(p, SMB_ENTRY_EANCHOR,
110 		    SMB_ENTRY_EANCHORLEN) == 0) {
111 			smb2 = p;
112 		}
113 
114 		p += SMB_SCAN_STEP;
115 	}
116 
117 	if (smb2 == NULL && smb3 == NULL) {
118 		psm_unmap_phys(bios, bioslen);
119 		return (smb_open_error(shp, errp, ESMB_NOTFOUND));
120 	}
121 
122 	/*
123 	 * While they're not supposed to (as per the SMBIOS 3.2 spec), some
124 	 * vendors end up having a newer version in one of the two entry points
125 	 * than the other. If we found multiple tables then we will prefer the
126 	 * one with the newer version. If they're equivalent, we prefer the
127 	 * 32-bit version. If only one is present, then we use that.
128 	 */
129 	ep = smb_alloc(SMB_ENTRY_MAXLEN);
130 	if (smb2 != NULL && smb3 != NULL) {
131 		uint8_t smb2maj, smb2min, smb3maj, smb3min;
132 
133 		bcopy(smb2, ep, sizeof (smbios_entry_t));
134 		smb2maj = ep->ep21.smbe_major;
135 		smb2min = ep->ep21.smbe_minor;
136 		bcopy(smb3, ep, sizeof (smbios_entry_t));
137 		smb3maj = ep->ep30.smbe_major;
138 		smb3min = ep->ep30.smbe_minor;
139 
140 		if (smb3maj > smb2maj ||
141 		    (smb3maj == smb2maj && smb3min > smb2min)) {
142 			ep_type = SMBIOS_ENTRY_POINT_30;
143 			p = smb3;
144 		} else {
145 			ep_type = SMBIOS_ENTRY_POINT_21;
146 			p = smb2;
147 		}
148 	} else if (smb3 != NULL) {
149 		ep_type = SMBIOS_ENTRY_POINT_30;
150 		p = smb3;
151 	} else {
152 		ep_type = SMBIOS_ENTRY_POINT_21;
153 		p = smb2;
154 	}
155 	bcopy(p, ep, sizeof (smbios_entry_t));
156 	if (ep_type == SMBIOS_ENTRY_POINT_21) {
157 		ep->ep21.smbe_elen = MIN(ep->ep21.smbe_elen, SMB_ENTRY_MAXLEN);
158 		bcopy(p, ep, ep->ep21.smbe_elen);
159 	} else if (ep_type == SMBIOS_ENTRY_POINT_30) {
160 		ep->ep30.smbe_elen = MIN(ep->ep30.smbe_elen, SMB_ENTRY_MAXLEN);
161 		bcopy(p, ep, ep->ep30.smbe_elen);
162 	}
163 
164 	psm_unmap_phys(bios, bioslen);
165 	switch (ep_type) {
166 	case SMBIOS_ENTRY_POINT_21:
167 		smbe_major = ep->ep21.smbe_major;
168 		smbe_minor = ep->ep21.smbe_minor;
169 		smbe_stlen = ep->ep21.smbe_stlen;
170 		bios = psm_map_phys(ep->ep21.smbe_staddr, smbe_stlen,
171 		    PSM_PROT_READ);
172 		break;
173 	case SMBIOS_ENTRY_POINT_30:
174 		smbe_major = ep->ep30.smbe_major;
175 		smbe_minor = ep->ep30.smbe_minor;
176 		smbe_stlen = ep->ep30.smbe_stlen;
177 		bios = psm_map_phys_new(ep->ep30.smbe_staddr, smbe_stlen,
178 		    PSM_PROT_READ);
179 		break;
180 	default:
181 		smb_free(ep, SMB_ENTRY_MAXLEN);
182 		return (smb_open_error(shp, errp, ESMB_VERSION));
183 	}
184 
185 	if (bios == NULL) {
186 		smb_free(ep, SMB_ENTRY_MAXLEN);
187 		return (smb_open_error(shp, errp, ESMB_MAPDEV));
188 	}
189 
190 	stbuf = smb_alloc(smbe_stlen);
191 	bcopy(bios, stbuf, smbe_stlen);
192 	psm_unmap_phys(bios, smbe_stlen);
193 	shp = smbios_bufopen(ep, stbuf, smbe_stlen, version, flags, &err);
194 
195 	if (shp == NULL) {
196 		smb_free(stbuf, smbe_stlen);
197 		smb_free(ep, SMB_ENTRY_MAXLEN);
198 		return (smb_open_error(shp, errp, err));
199 	}
200 
201 	if (ksmbios == NULL) {
202 		cmn_err(CE_CONT, "?SMBIOS v%u.%u loaded (%u bytes)",
203 		    smbe_major, smbe_minor, smbe_stlen);
204 		if (shp->sh_flags & SMB_FL_TRUNC)
205 			cmn_err(CE_CONT, "?SMBIOS table is truncated");
206 	}
207 
208 	shp->sh_flags |= SMB_FL_BUFALLOC;
209 	smb_free(ep, SMB_ENTRY_MAXLEN);
210 
211 	return (shp);
212 }
213 
214 /*ARGSUSED*/
215 smbios_hdl_t *
216 smbios_fdopen(int fd, int version, int flags, int *errp)
217 {
218 	return (smb_open_error(NULL, errp, ENOTSUP));
219 }
220 
221 /*ARGSUSED*/
222 int
223 smbios_write(smbios_hdl_t *shp, int fd)
224 {
225 	return (smb_set_errno(shp, ENOTSUP));
226 }
227