1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * S/390 common I/O routines -- blacklisting of specific devices |
4 | * |
5 | * Copyright IBM Corp. 1999, 2013 |
6 | * Author(s): Ingo Adlung (adlung@de.ibm.com) |
7 | * Cornelia Huck (cornelia.huck@de.ibm.com) |
8 | * Arnd Bergmann (arndb@de.ibm.com) |
9 | */ |
10 | |
11 | #define KMSG_COMPONENT "cio" |
12 | #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt |
13 | |
14 | #include <linux/init.h> |
15 | #include <linux/vmalloc.h> |
16 | #include <linux/proc_fs.h> |
17 | #include <linux/seq_file.h> |
18 | #include <linux/ctype.h> |
19 | #include <linux/device.h> |
20 | |
21 | #include <linux/uaccess.h> |
22 | #include <asm/cio.h> |
23 | #include <asm/ipl.h> |
24 | |
25 | #include "blacklist.h" |
26 | #include "cio.h" |
27 | #include "cio_debug.h" |
28 | #include "css.h" |
29 | #include "device.h" |
30 | |
31 | /* |
32 | * "Blacklisting" of certain devices: |
33 | * Device numbers given in the commandline as cio_ignore=... won't be known |
34 | * to Linux. |
35 | * |
36 | * These can be single devices or ranges of devices |
37 | */ |
38 | |
39 | /* 65536 bits for each set to indicate if a devno is blacklisted or not */ |
40 | #define __BL_DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \ |
41 | (8*sizeof(long))) |
42 | static unsigned long bl_dev[__MAX_SSID + 1][__BL_DEV_WORDS]; |
43 | typedef enum {add, free} range_action; |
44 | |
45 | /* |
46 | * Function: blacklist_range |
47 | * (Un-)blacklist the devices from-to |
48 | */ |
49 | static int blacklist_range(range_action action, unsigned int from_ssid, |
50 | unsigned int to_ssid, unsigned int from, |
51 | unsigned int to, int msgtrigger) |
52 | { |
53 | if ((from_ssid > to_ssid) || ((from_ssid == to_ssid) && (from > to))) { |
54 | if (msgtrigger) |
55 | pr_warn("0.%x.%04x to 0.%x.%04x is not a valid range for cio_ignore\n" , |
56 | from_ssid, from, to_ssid, to); |
57 | |
58 | return 1; |
59 | } |
60 | |
61 | while ((from_ssid < to_ssid) || ((from_ssid == to_ssid) && |
62 | (from <= to))) { |
63 | if (action == add) |
64 | set_bit(nr: from, addr: bl_dev[from_ssid]); |
65 | else |
66 | clear_bit(nr: from, addr: bl_dev[from_ssid]); |
67 | from++; |
68 | if (from > __MAX_SUBCHANNEL) { |
69 | from_ssid++; |
70 | from = 0; |
71 | } |
72 | } |
73 | |
74 | return 0; |
75 | } |
76 | |
77 | static int pure_hex(char **cp, unsigned int *val, int min_digit, |
78 | int max_digit, int max_val) |
79 | { |
80 | int diff; |
81 | |
82 | diff = 0; |
83 | *val = 0; |
84 | |
85 | while (diff <= max_digit) { |
86 | int value = hex_to_bin(ch: **cp); |
87 | |
88 | if (value < 0) |
89 | break; |
90 | *val = *val * 16 + value; |
91 | (*cp)++; |
92 | diff++; |
93 | } |
94 | |
95 | if ((diff < min_digit) || (diff > max_digit) || (*val > max_val)) |
96 | return 1; |
97 | |
98 | return 0; |
99 | } |
100 | |
101 | static int parse_busid(char *str, unsigned int *cssid, unsigned int *ssid, |
102 | unsigned int *devno, int msgtrigger) |
103 | { |
104 | char *str_work; |
105 | int val, rc, ret; |
106 | |
107 | rc = 1; |
108 | |
109 | if (*str == '\0') |
110 | goto out; |
111 | |
112 | /* old style */ |
113 | str_work = str; |
114 | val = simple_strtoul(str, &str_work, 16); |
115 | |
116 | if (*str_work == '\0') { |
117 | if (val <= __MAX_SUBCHANNEL) { |
118 | *devno = val; |
119 | *ssid = 0; |
120 | *cssid = 0; |
121 | rc = 0; |
122 | } |
123 | goto out; |
124 | } |
125 | |
126 | /* new style */ |
127 | str_work = str; |
128 | ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID); |
129 | if (ret || (str_work[0] != '.')) |
130 | goto out; |
131 | str_work++; |
132 | ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID); |
133 | if (ret || (str_work[0] != '.')) |
134 | goto out; |
135 | str_work++; |
136 | ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL); |
137 | if (ret || (str_work[0] != '\0')) |
138 | goto out; |
139 | |
140 | rc = 0; |
141 | out: |
142 | if (rc && msgtrigger) |
143 | pr_warn("%s is not a valid device for the cio_ignore kernel parameter\n" , |
144 | str); |
145 | |
146 | return rc; |
147 | } |
148 | |
149 | static int blacklist_parse_parameters(char *str, range_action action, |
150 | int msgtrigger) |
151 | { |
152 | unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to; |
153 | int rc, totalrc; |
154 | char *parm; |
155 | range_action ra; |
156 | |
157 | totalrc = 0; |
158 | |
159 | while ((parm = strsep(&str, "," ))) { |
160 | rc = 0; |
161 | ra = action; |
162 | if (*parm == '!') { |
163 | if (ra == add) |
164 | ra = free; |
165 | else |
166 | ra = add; |
167 | parm++; |
168 | } |
169 | if (strcmp(parm, "all" ) == 0) { |
170 | from_cssid = 0; |
171 | from_ssid = 0; |
172 | from = 0; |
173 | to_cssid = __MAX_CSSID; |
174 | to_ssid = __MAX_SSID; |
175 | to = __MAX_SUBCHANNEL; |
176 | } else if (strcmp(parm, "ipldev" ) == 0) { |
177 | if (ipl_info.type == IPL_TYPE_CCW) { |
178 | from_cssid = 0; |
179 | from_ssid = ipl_info.data.ccw.dev_id.ssid; |
180 | from = ipl_info.data.ccw.dev_id.devno; |
181 | } else if (ipl_info.type == IPL_TYPE_FCP || |
182 | ipl_info.type == IPL_TYPE_FCP_DUMP) { |
183 | from_cssid = 0; |
184 | from_ssid = ipl_info.data.fcp.dev_id.ssid; |
185 | from = ipl_info.data.fcp.dev_id.devno; |
186 | } else { |
187 | continue; |
188 | } |
189 | to_cssid = from_cssid; |
190 | to_ssid = from_ssid; |
191 | to = from; |
192 | } else if (strcmp(parm, "condev" ) == 0) { |
193 | if (console_devno == -1) |
194 | continue; |
195 | |
196 | from_cssid = to_cssid = 0; |
197 | from_ssid = to_ssid = 0; |
198 | from = to = console_devno; |
199 | } else { |
200 | rc = parse_busid(str: strsep(&parm, "-" ), cssid: &from_cssid, |
201 | ssid: &from_ssid, devno: &from, msgtrigger); |
202 | if (!rc) { |
203 | if (parm != NULL) |
204 | rc = parse_busid(str: parm, cssid: &to_cssid, |
205 | ssid: &to_ssid, devno: &to, |
206 | msgtrigger); |
207 | else { |
208 | to_cssid = from_cssid; |
209 | to_ssid = from_ssid; |
210 | to = from; |
211 | } |
212 | } |
213 | } |
214 | if (!rc) { |
215 | rc = blacklist_range(action: ra, from_ssid, to_ssid, from, to, |
216 | msgtrigger); |
217 | if (rc) |
218 | totalrc = -EINVAL; |
219 | } else |
220 | totalrc = -EINVAL; |
221 | } |
222 | |
223 | return totalrc; |
224 | } |
225 | |
226 | static int __init |
227 | blacklist_setup (char *str) |
228 | { |
229 | CIO_MSG_EVENT(6, "Reading blacklist parameters\n" ); |
230 | if (blacklist_parse_parameters(str, action: add, msgtrigger: 1)) |
231 | return 0; |
232 | return 1; |
233 | } |
234 | |
235 | __setup ("cio_ignore=" , blacklist_setup); |
236 | |
237 | /* Checking if devices are blacklisted */ |
238 | |
239 | /* |
240 | * Function: is_blacklisted |
241 | * Returns 1 if the given devicenumber can be found in the blacklist, |
242 | * otherwise 0. |
243 | * Used by validate_subchannel() |
244 | */ |
245 | int |
246 | is_blacklisted (int ssid, int devno) |
247 | { |
248 | return test_bit (devno, bl_dev[ssid]); |
249 | } |
250 | |
251 | #ifdef CONFIG_PROC_FS |
252 | /* |
253 | * Function: blacklist_parse_proc_parameters |
254 | * parse the stuff which is piped to /proc/cio_ignore |
255 | */ |
256 | static int blacklist_parse_proc_parameters(char *buf) |
257 | { |
258 | int rc; |
259 | char *parm; |
260 | |
261 | parm = strsep(&buf, " " ); |
262 | |
263 | if (strcmp("free" , parm) == 0) { |
264 | rc = blacklist_parse_parameters(str: buf, action: free, msgtrigger: 0); |
265 | /* |
266 | * Evaluate the subchannels without an online device. This way, |
267 | * no path-verification will be triggered on those subchannels |
268 | * and it avoids unnecessary delays. |
269 | */ |
270 | css_schedule_eval_cond(CSS_EVAL_NOT_ONLINE, delay: 0); |
271 | } else if (strcmp("add" , parm) == 0) |
272 | rc = blacklist_parse_parameters(str: buf, action: add, msgtrigger: 0); |
273 | else if (strcmp("purge" , parm) == 0) |
274 | return ccw_purge_blacklisted(); |
275 | else |
276 | return -EINVAL; |
277 | |
278 | |
279 | return rc; |
280 | } |
281 | |
282 | /* Iterator struct for all devices. */ |
283 | struct ccwdev_iter { |
284 | int devno; |
285 | int ssid; |
286 | int in_range; |
287 | }; |
288 | |
289 | static void * |
290 | cio_ignore_proc_seq_start(struct seq_file *s, loff_t *offset) |
291 | { |
292 | struct ccwdev_iter *iter = s->private; |
293 | |
294 | if (*offset >= (__MAX_SUBCHANNEL + 1) * (__MAX_SSID + 1)) |
295 | return NULL; |
296 | memset(iter, 0, sizeof(*iter)); |
297 | iter->ssid = *offset / (__MAX_SUBCHANNEL + 1); |
298 | iter->devno = *offset % (__MAX_SUBCHANNEL + 1); |
299 | return iter; |
300 | } |
301 | |
302 | static void |
303 | cio_ignore_proc_seq_stop(struct seq_file *s, void *it) |
304 | { |
305 | } |
306 | |
307 | static void * |
308 | cio_ignore_proc_seq_next(struct seq_file *s, void *it, loff_t *offset) |
309 | { |
310 | struct ccwdev_iter *iter; |
311 | loff_t p = *offset; |
312 | |
313 | (*offset)++; |
314 | if (p >= (__MAX_SUBCHANNEL + 1) * (__MAX_SSID + 1)) |
315 | return NULL; |
316 | iter = it; |
317 | if (iter->devno == __MAX_SUBCHANNEL) { |
318 | iter->devno = 0; |
319 | iter->ssid++; |
320 | if (iter->ssid > __MAX_SSID) |
321 | return NULL; |
322 | } else |
323 | iter->devno++; |
324 | return iter; |
325 | } |
326 | |
327 | static int |
328 | cio_ignore_proc_seq_show(struct seq_file *s, void *it) |
329 | { |
330 | struct ccwdev_iter *iter; |
331 | |
332 | iter = it; |
333 | if (!is_blacklisted(ssid: iter->ssid, devno: iter->devno)) |
334 | /* Not blacklisted, nothing to output. */ |
335 | return 0; |
336 | if (!iter->in_range) { |
337 | /* First device in range. */ |
338 | if ((iter->devno == __MAX_SUBCHANNEL) || |
339 | !is_blacklisted(iter->ssid, iter->devno + 1)) { |
340 | /* Singular device. */ |
341 | seq_printf(m: s, fmt: "0.%x.%04x\n" , iter->ssid, iter->devno); |
342 | return 0; |
343 | } |
344 | iter->in_range = 1; |
345 | seq_printf(m: s, fmt: "0.%x.%04x-" , iter->ssid, iter->devno); |
346 | return 0; |
347 | } |
348 | if ((iter->devno == __MAX_SUBCHANNEL) || |
349 | !is_blacklisted(iter->ssid, iter->devno + 1)) { |
350 | /* Last device in range. */ |
351 | iter->in_range = 0; |
352 | seq_printf(m: s, fmt: "0.%x.%04x\n" , iter->ssid, iter->devno); |
353 | } |
354 | return 0; |
355 | } |
356 | |
357 | static ssize_t |
358 | cio_ignore_write(struct file *file, const char __user *user_buf, |
359 | size_t user_len, loff_t *offset) |
360 | { |
361 | char *buf; |
362 | ssize_t rc, ret, i; |
363 | |
364 | if (*offset) |
365 | return -EINVAL; |
366 | if (user_len > 65536) |
367 | user_len = 65536; |
368 | buf = vzalloc(size: user_len + 1); /* maybe better use the stack? */ |
369 | if (buf == NULL) |
370 | return -ENOMEM; |
371 | |
372 | if (strncpy_from_user (dst: buf, src: user_buf, count: user_len) < 0) { |
373 | rc = -EFAULT; |
374 | goto out_free; |
375 | } |
376 | |
377 | i = user_len - 1; |
378 | while ((i >= 0) && (isspace(buf[i]) || (buf[i] == 0))) { |
379 | buf[i] = '\0'; |
380 | i--; |
381 | } |
382 | ret = blacklist_parse_proc_parameters(buf); |
383 | if (ret) |
384 | rc = ret; |
385 | else |
386 | rc = user_len; |
387 | |
388 | out_free: |
389 | vfree (addr: buf); |
390 | return rc; |
391 | } |
392 | |
393 | static const struct seq_operations cio_ignore_proc_seq_ops = { |
394 | .start = cio_ignore_proc_seq_start, |
395 | .stop = cio_ignore_proc_seq_stop, |
396 | .next = cio_ignore_proc_seq_next, |
397 | .show = cio_ignore_proc_seq_show, |
398 | }; |
399 | |
400 | static int |
401 | cio_ignore_proc_open(struct inode *inode, struct file *file) |
402 | { |
403 | return seq_open_private(file, &cio_ignore_proc_seq_ops, |
404 | sizeof(struct ccwdev_iter)); |
405 | } |
406 | |
407 | static const struct proc_ops cio_ignore_proc_ops = { |
408 | .proc_open = cio_ignore_proc_open, |
409 | .proc_read = seq_read, |
410 | .proc_lseek = seq_lseek, |
411 | .proc_release = seq_release_private, |
412 | .proc_write = cio_ignore_write, |
413 | }; |
414 | |
415 | static int |
416 | cio_ignore_proc_init (void) |
417 | { |
418 | struct proc_dir_entry *entry; |
419 | |
420 | entry = proc_create(name: "cio_ignore" , S_IFREG | S_IRUGO | S_IWUSR, NULL, |
421 | proc_ops: &cio_ignore_proc_ops); |
422 | if (!entry) |
423 | return -ENOENT; |
424 | return 0; |
425 | } |
426 | |
427 | __initcall (cio_ignore_proc_init); |
428 | |
429 | #endif /* CONFIG_PROC_FS */ |
430 | |