xref: /linux-6.15/scripts/mod/file2alias.c (revision 1da177e4)
1 /* Simple code to turn various tables in an ELF file into alias definitions.
2  * This deals with kernel datastructures where they should be
3  * dealt with: in the kernel source.
4  *
5  * Copyright 2002-2003  Rusty Russell, IBM Corporation
6  *           2003       Kai Germaschewski
7  *
8  *
9  * This software may be used and distributed according to the terms
10  * of the GNU General Public License, incorporated herein by reference.
11  */
12 
13 #include "modpost.h"
14 
15 /* We use the ELF typedefs for kernel_ulong_t but bite the bullet and
16  * use either stdint.h or inttypes.h for the rest. */
17 #if KERNEL_ELFCLASS == ELFCLASS32
18 typedef Elf32_Addr	kernel_ulong_t;
19 #else
20 typedef Elf64_Addr	kernel_ulong_t;
21 #endif
22 #ifdef __sun__
23 #include <inttypes.h>
24 #else
25 #include <stdint.h>
26 #endif
27 
28 typedef uint32_t	__u32;
29 typedef uint16_t	__u16;
30 typedef unsigned char	__u8;
31 
32 /* Big exception to the "don't include kernel headers into userspace, which
33  * even potentially has different endianness and word sizes, since
34  * we handle those differences explicitly below */
35 #include "../../include/linux/mod_devicetable.h"
36 
37 #define ADD(str, sep, cond, field)                              \
38 do {                                                            \
39         strcat(str, sep);                                       \
40         if (cond)                                               \
41                 sprintf(str + strlen(str),                      \
42                         sizeof(field) == 1 ? "%02X" :           \
43                         sizeof(field) == 2 ? "%04X" :           \
44                         sizeof(field) == 4 ? "%08X" : "",       \
45                         field);                                 \
46         else                                                    \
47                 sprintf(str + strlen(str), "*");                \
48 } while(0)
49 
50 /* Looks like "usb:vNpNdlNdhNdcNdscNdpNicNiscNipN" */
51 static int do_usb_entry(const char *filename,
52 			struct usb_device_id *id, char *alias)
53 {
54 	id->match_flags = TO_NATIVE(id->match_flags);
55 	id->idVendor = TO_NATIVE(id->idVendor);
56 	id->idProduct = TO_NATIVE(id->idProduct);
57 	id->bcdDevice_lo = TO_NATIVE(id->bcdDevice_lo);
58 	id->bcdDevice_hi = TO_NATIVE(id->bcdDevice_hi);
59 
60 	/*
61 	 * Some modules (visor) have empty slots as placeholder for
62 	 * run-time specification that results in catch-all alias
63 	 */
64 	if (!(id->idVendor | id->bDeviceClass | id->bInterfaceClass))
65 		return 1;
66 
67 	strcpy(alias, "usb:");
68 	ADD(alias, "v", id->match_flags&USB_DEVICE_ID_MATCH_VENDOR,
69 	    id->idVendor);
70 	ADD(alias, "p", id->match_flags&USB_DEVICE_ID_MATCH_PRODUCT,
71 	    id->idProduct);
72 	ADD(alias, "dl", id->match_flags&USB_DEVICE_ID_MATCH_DEV_LO,
73 	    id->bcdDevice_lo);
74 	ADD(alias, "dh", id->match_flags&USB_DEVICE_ID_MATCH_DEV_HI,
75 	    id->bcdDevice_hi);
76 	ADD(alias, "dc", id->match_flags&USB_DEVICE_ID_MATCH_DEV_CLASS,
77 	    id->bDeviceClass);
78 	ADD(alias, "dsc",
79 	    id->match_flags&USB_DEVICE_ID_MATCH_DEV_SUBCLASS,
80 	    id->bDeviceSubClass);
81 	ADD(alias, "dp",
82 	    id->match_flags&USB_DEVICE_ID_MATCH_DEV_PROTOCOL,
83 	    id->bDeviceProtocol);
84 	ADD(alias, "ic",
85 	    id->match_flags&USB_DEVICE_ID_MATCH_INT_CLASS,
86 	    id->bInterfaceClass);
87 	ADD(alias, "isc",
88 	    id->match_flags&USB_DEVICE_ID_MATCH_INT_SUBCLASS,
89 	    id->bInterfaceSubClass);
90 	ADD(alias, "ip",
91 	    id->match_flags&USB_DEVICE_ID_MATCH_INT_PROTOCOL,
92 	    id->bInterfaceProtocol);
93 	return 1;
94 }
95 
96 /* Looks like: ieee1394:venNmoNspNverN */
97 static int do_ieee1394_entry(const char *filename,
98 			     struct ieee1394_device_id *id, char *alias)
99 {
100 	id->match_flags = TO_NATIVE(id->match_flags);
101 	id->vendor_id = TO_NATIVE(id->vendor_id);
102 	id->model_id = TO_NATIVE(id->model_id);
103 	id->specifier_id = TO_NATIVE(id->specifier_id);
104 	id->version = TO_NATIVE(id->version);
105 
106 	strcpy(alias, "ieee1394:");
107 	ADD(alias, "ven", id->match_flags & IEEE1394_MATCH_VENDOR_ID,
108 	    id->vendor_id);
109 	ADD(alias, "mo", id->match_flags & IEEE1394_MATCH_MODEL_ID,
110 	    id->model_id);
111 	ADD(alias, "sp", id->match_flags & IEEE1394_MATCH_SPECIFIER_ID,
112 	    id->specifier_id);
113 	ADD(alias, "ver", id->match_flags & IEEE1394_MATCH_VERSION,
114 	    id->version);
115 
116 	return 1;
117 }
118 
119 /* Looks like: pci:vNdNsvNsdNbcNscNiN. */
120 static int do_pci_entry(const char *filename,
121 			struct pci_device_id *id, char *alias)
122 {
123 	/* Class field can be divided into these three. */
124 	unsigned char baseclass, subclass, interface,
125 		baseclass_mask, subclass_mask, interface_mask;
126 
127 	id->vendor = TO_NATIVE(id->vendor);
128 	id->device = TO_NATIVE(id->device);
129 	id->subvendor = TO_NATIVE(id->subvendor);
130 	id->subdevice = TO_NATIVE(id->subdevice);
131 	id->class = TO_NATIVE(id->class);
132 	id->class_mask = TO_NATIVE(id->class_mask);
133 
134 	strcpy(alias, "pci:");
135 	ADD(alias, "v", id->vendor != PCI_ANY_ID, id->vendor);
136 	ADD(alias, "d", id->device != PCI_ANY_ID, id->device);
137 	ADD(alias, "sv", id->subvendor != PCI_ANY_ID, id->subvendor);
138 	ADD(alias, "sd", id->subdevice != PCI_ANY_ID, id->subdevice);
139 
140 	baseclass = (id->class) >> 16;
141 	baseclass_mask = (id->class_mask) >> 16;
142 	subclass = (id->class) >> 8;
143 	subclass_mask = (id->class_mask) >> 8;
144 	interface = id->class;
145 	interface_mask = id->class_mask;
146 
147 	if ((baseclass_mask != 0 && baseclass_mask != 0xFF)
148 	    || (subclass_mask != 0 && subclass_mask != 0xFF)
149 	    || (interface_mask != 0 && interface_mask != 0xFF)) {
150 		fprintf(stderr,
151 			"*** Warning: Can't handle masks in %s:%04X\n",
152 			filename, id->class_mask);
153 		return 0;
154 	}
155 
156 	ADD(alias, "bc", baseclass_mask == 0xFF, baseclass);
157 	ADD(alias, "sc", subclass_mask == 0xFF, subclass);
158 	ADD(alias, "i", interface_mask == 0xFF, interface);
159 	return 1;
160 }
161 
162 /* looks like: "ccw:tNmNdtNdmN" */
163 static int do_ccw_entry(const char *filename,
164 			struct ccw_device_id *id, char *alias)
165 {
166 	id->match_flags = TO_NATIVE(id->match_flags);
167 	id->cu_type = TO_NATIVE(id->cu_type);
168 	id->cu_model = TO_NATIVE(id->cu_model);
169 	id->dev_type = TO_NATIVE(id->dev_type);
170 	id->dev_model = TO_NATIVE(id->dev_model);
171 
172 	strcpy(alias, "ccw:");
173 	ADD(alias, "t", id->match_flags&CCW_DEVICE_ID_MATCH_CU_TYPE,
174 	    id->cu_type);
175 	ADD(alias, "m", id->match_flags&CCW_DEVICE_ID_MATCH_CU_MODEL,
176 	    id->cu_model);
177 	ADD(alias, "dt", id->match_flags&CCW_DEVICE_ID_MATCH_DEVICE_TYPE,
178 	    id->dev_type);
179 	ADD(alias, "dm", id->match_flags&CCW_DEVICE_ID_MATCH_DEVICE_TYPE,
180 	    id->dev_model);
181 	return 1;
182 }
183 
184 /* Looks like: "serio:tyNprNidNexN" */
185 static int do_serio_entry(const char *filename,
186 			  struct serio_device_id *id, char *alias)
187 {
188 	id->type = TO_NATIVE(id->type);
189 	id->proto = TO_NATIVE(id->proto);
190 	id->id = TO_NATIVE(id->id);
191 	id->extra = TO_NATIVE(id->extra);
192 
193 	strcpy(alias, "serio:");
194 	ADD(alias, "ty", id->type != SERIO_ANY, id->type);
195 	ADD(alias, "pr", id->proto != SERIO_ANY, id->proto);
196 	ADD(alias, "id", id->id != SERIO_ANY, id->id);
197 	ADD(alias, "ex", id->extra != SERIO_ANY, id->extra);
198 
199 	return 1;
200 }
201 
202 /* looks like: "pnp:dD" */
203 static int do_pnp_entry(const char *filename,
204 			struct pnp_device_id *id, char *alias)
205 {
206 	sprintf(alias, "pnp:d%s", id->id);
207 	return 1;
208 }
209 
210 /* looks like: "pnp:cCdD..." */
211 static int do_pnp_card_entry(const char *filename,
212 			struct pnp_card_device_id *id, char *alias)
213 {
214 	int i;
215 
216 	sprintf(alias, "pnp:c%s", id->id);
217 	for (i = 0; i < PNP_MAX_DEVICES; i++) {
218 		if (! *id->devs[i].id)
219 			break;
220 		sprintf(alias + strlen(alias), "d%s", id->devs[i].id);
221 	}
222 	return 1;
223 }
224 
225 /* Ignore any prefix, eg. v850 prepends _ */
226 static inline int sym_is(const char *symbol, const char *name)
227 {
228 	const char *match;
229 
230 	match = strstr(symbol, name);
231 	if (!match)
232 		return 0;
233 	return match[strlen(symbol)] == '\0';
234 }
235 
236 static void do_table(void *symval, unsigned long size,
237 		     unsigned long id_size,
238 		     void *function,
239 		     struct module *mod)
240 {
241 	unsigned int i;
242 	char alias[500];
243 	int (*do_entry)(const char *, void *entry, char *alias) = function;
244 
245 	if (size % id_size || size < id_size) {
246 		fprintf(stderr, "*** Warning: %s ids %lu bad size "
247 			"(each on %lu)\n", mod->name, size, id_size);
248 	}
249 	/* Leave last one: it's the terminator. */
250 	size -= id_size;
251 
252 	for (i = 0; i < size; i += id_size) {
253 		if (do_entry(mod->name, symval+i, alias)) {
254 			/* Always end in a wildcard, for future extension */
255 			if (alias[strlen(alias)-1] != '*')
256 				strcat(alias, "*");
257 			buf_printf(&mod->dev_table_buf,
258 				   "MODULE_ALIAS(\"%s\");\n", alias);
259 		}
260 	}
261 }
262 
263 /* Create MODULE_ALIAS() statements.
264  * At this time, we cannot write the actual output C source yet,
265  * so we write into the mod->dev_table_buf buffer. */
266 void handle_moddevtable(struct module *mod, struct elf_info *info,
267 			Elf_Sym *sym, const char *symname)
268 {
269 	void *symval;
270 
271 	/* We're looking for a section relative symbol */
272 	if (!sym->st_shndx || sym->st_shndx >= info->hdr->e_shnum)
273 		return;
274 
275 	symval = (void *)info->hdr
276 		+ info->sechdrs[sym->st_shndx].sh_offset
277 		+ sym->st_value;
278 
279 	if (sym_is(symname, "__mod_pci_device_table"))
280 		do_table(symval, sym->st_size, sizeof(struct pci_device_id),
281 			 do_pci_entry, mod);
282 	else if (sym_is(symname, "__mod_usb_device_table"))
283 		do_table(symval, sym->st_size, sizeof(struct usb_device_id),
284 			 do_usb_entry, mod);
285 	else if (sym_is(symname, "__mod_ieee1394_device_table"))
286 		do_table(symval, sym->st_size, sizeof(struct ieee1394_device_id),
287 			 do_ieee1394_entry, mod);
288 	else if (sym_is(symname, "__mod_ccw_device_table"))
289 		do_table(symval, sym->st_size, sizeof(struct ccw_device_id),
290 			 do_ccw_entry, mod);
291 	else if (sym_is(symname, "__mod_serio_device_table"))
292 		do_table(symval, sym->st_size, sizeof(struct serio_device_id),
293 			 do_serio_entry, mod);
294 	else if (sym_is(symname, "__mod_pnp_device_table"))
295 		do_table(symval, sym->st_size, sizeof(struct pnp_device_id),
296 			 do_pnp_entry, mod);
297 	else if (sym_is(symname, "__mod_pnp_card_device_table"))
298 		do_table(symval, sym->st_size, sizeof(struct pnp_card_device_id),
299 			 do_pnp_card_entry, mod);
300 }
301 
302 /* Now add out buffered information to the generated C source */
303 void add_moddevtable(struct buffer *buf, struct module *mod)
304 {
305 	buf_printf(buf, "\n");
306 	buf_write(buf, mod->dev_table_buf.p, mod->dev_table_buf.pos);
307 	free(mod->dev_table_buf.p);
308 }
309