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Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
db705e83 | 2 | * Collaborative memory management interface. |
1da177e4 | 3 | * |
db705e83 HC |
4 | * Copyright IBM Corp 2003,2010 |
5 | * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>, | |
1da177e4 | 6 | * |
1da177e4 LT |
7 | */ |
8 | ||
1da177e4 LT |
9 | #include <linux/errno.h> |
10 | #include <linux/fs.h> | |
11 | #include <linux/init.h> | |
12 | #include <linux/module.h> | |
5a0e3ad6 | 13 | #include <linux/gfp.h> |
1da177e4 LT |
14 | #include <linux/sched.h> |
15 | #include <linux/sysctl.h> | |
16 | #include <linux/ctype.h> | |
8bc719d3 | 17 | #include <linux/swap.h> |
e8216dee | 18 | #include <linux/kthread.h> |
5a3135c2 | 19 | #include <linux/oom.h> |
52b169c8 | 20 | #include <linux/suspend.h> |
db705e83 | 21 | #include <linux/uaccess.h> |
1da177e4 LT |
22 | |
23 | #include <asm/pgalloc.h> | |
0a87c5cf | 24 | #include <asm/diag.h> |
1da177e4 | 25 | |
a20852d2 HC |
26 | #ifdef CONFIG_CMM_IUCV |
27 | static char *cmm_default_sender = "VMRMSVM"; | |
28 | #endif | |
29 | static char *sender; | |
447570cf | 30 | module_param(sender, charp, 0400); |
15439d74 MS |
31 | MODULE_PARM_DESC(sender, |
32 | "Guest name that may send SMSG messages (default VMRMSVM)"); | |
33 | ||
1da177e4 LT |
34 | #include "../../../drivers/s390/net/smsgiucv.h" |
35 | ||
36 | #define CMM_NR_PAGES ((PAGE_SIZE / sizeof(unsigned long)) - 2) | |
37 | ||
38 | struct cmm_page_array { | |
39 | struct cmm_page_array *next; | |
40 | unsigned long index; | |
41 | unsigned long pages[CMM_NR_PAGES]; | |
42 | }; | |
43 | ||
8bc719d3 MS |
44 | static long cmm_pages; |
45 | static long cmm_timed_pages; | |
46 | static volatile long cmm_pages_target; | |
47 | static volatile long cmm_timed_pages_target; | |
48 | static long cmm_timeout_pages; | |
49 | static long cmm_timeout_seconds; | |
52b169c8 | 50 | static int cmm_suspended; |
1da177e4 | 51 | |
8bc719d3 MS |
52 | static struct cmm_page_array *cmm_page_list; |
53 | static struct cmm_page_array *cmm_timed_page_list; | |
54 | static DEFINE_SPINLOCK(cmm_lock); | |
1da177e4 | 55 | |
e8216dee | 56 | static struct task_struct *cmm_thread_ptr; |
1ef6acf5 HC |
57 | static DECLARE_WAIT_QUEUE_HEAD(cmm_thread_wait); |
58 | static DEFINE_TIMER(cmm_timer, NULL, 0, 0); | |
1da177e4 LT |
59 | |
60 | static void cmm_timer_fn(unsigned long); | |
61 | static void cmm_set_timer(void); | |
62 | ||
db705e83 HC |
63 | static long cmm_alloc_pages(long nr, long *counter, |
64 | struct cmm_page_array **list) | |
1da177e4 | 65 | { |
8bc719d3 MS |
66 | struct cmm_page_array *pa, *npa; |
67 | unsigned long addr; | |
1da177e4 | 68 | |
8bc719d3 MS |
69 | while (nr) { |
70 | addr = __get_free_page(GFP_NOIO); | |
71 | if (!addr) | |
1da177e4 | 72 | break; |
8bc719d3 MS |
73 | spin_lock(&cmm_lock); |
74 | pa = *list; | |
1da177e4 LT |
75 | if (!pa || pa->index >= CMM_NR_PAGES) { |
76 | /* Need a new page for the page list. */ | |
8bc719d3 MS |
77 | spin_unlock(&cmm_lock); |
78 | npa = (struct cmm_page_array *) | |
1da177e4 | 79 | __get_free_page(GFP_NOIO); |
8bc719d3 MS |
80 | if (!npa) { |
81 | free_page(addr); | |
1da177e4 LT |
82 | break; |
83 | } | |
8bc719d3 MS |
84 | spin_lock(&cmm_lock); |
85 | pa = *list; | |
86 | if (!pa || pa->index >= CMM_NR_PAGES) { | |
87 | npa->next = pa; | |
88 | npa->index = 0; | |
89 | pa = npa; | |
90 | *list = pa; | |
91 | } else | |
92 | free_page((unsigned long) npa); | |
1da177e4 | 93 | } |
83ace270 | 94 | diag10_range(addr >> PAGE_SHIFT, 1); |
8bc719d3 | 95 | pa->pages[pa->index++] = addr; |
1da177e4 | 96 | (*counter)++; |
8bc719d3 MS |
97 | spin_unlock(&cmm_lock); |
98 | nr--; | |
1da177e4 | 99 | } |
8bc719d3 | 100 | return nr; |
1da177e4 LT |
101 | } |
102 | ||
db705e83 | 103 | static long cmm_free_pages(long nr, long *counter, struct cmm_page_array **list) |
1da177e4 LT |
104 | { |
105 | struct cmm_page_array *pa; | |
8bc719d3 | 106 | unsigned long addr; |
1da177e4 | 107 | |
8bc719d3 | 108 | spin_lock(&cmm_lock); |
1da177e4 | 109 | pa = *list; |
8bc719d3 | 110 | while (nr) { |
1da177e4 LT |
111 | if (!pa || pa->index <= 0) |
112 | break; | |
8bc719d3 | 113 | addr = pa->pages[--pa->index]; |
1da177e4 LT |
114 | if (pa->index == 0) { |
115 | pa = pa->next; | |
116 | free_page((unsigned long) *list); | |
117 | *list = pa; | |
118 | } | |
8bc719d3 | 119 | free_page(addr); |
1da177e4 | 120 | (*counter)--; |
8bc719d3 | 121 | nr--; |
1da177e4 | 122 | } |
8bc719d3 MS |
123 | spin_unlock(&cmm_lock); |
124 | return nr; | |
1da177e4 LT |
125 | } |
126 | ||
8bc719d3 MS |
127 | static int cmm_oom_notify(struct notifier_block *self, |
128 | unsigned long dummy, void *parm) | |
129 | { | |
130 | unsigned long *freed = parm; | |
131 | long nr = 256; | |
132 | ||
133 | nr = cmm_free_pages(nr, &cmm_timed_pages, &cmm_timed_page_list); | |
134 | if (nr > 0) | |
135 | nr = cmm_free_pages(nr, &cmm_pages, &cmm_page_list); | |
136 | cmm_pages_target = cmm_pages; | |
137 | cmm_timed_pages_target = cmm_timed_pages; | |
138 | *freed += 256 - nr; | |
139 | return NOTIFY_OK; | |
140 | } | |
141 | ||
142 | static struct notifier_block cmm_oom_nb = { | |
db705e83 | 143 | .notifier_call = cmm_oom_notify, |
8bc719d3 MS |
144 | }; |
145 | ||
db705e83 | 146 | static int cmm_thread(void *dummy) |
1da177e4 LT |
147 | { |
148 | int rc; | |
149 | ||
1da177e4 LT |
150 | while (1) { |
151 | rc = wait_event_interruptible(cmm_thread_wait, | |
52b169c8 MS |
152 | (!cmm_suspended && (cmm_pages != cmm_pages_target || |
153 | cmm_timed_pages != cmm_timed_pages_target)) || | |
154 | kthread_should_stop()); | |
e8216dee | 155 | if (kthread_should_stop() || rc == -ERESTARTSYS) { |
1da177e4 LT |
156 | cmm_pages_target = cmm_pages; |
157 | cmm_timed_pages_target = cmm_timed_pages; | |
158 | break; | |
159 | } | |
160 | if (cmm_pages_target > cmm_pages) { | |
161 | if (cmm_alloc_pages(1, &cmm_pages, &cmm_page_list)) | |
162 | cmm_pages_target = cmm_pages; | |
163 | } else if (cmm_pages_target < cmm_pages) { | |
164 | cmm_free_pages(1, &cmm_pages, &cmm_page_list); | |
165 | } | |
166 | if (cmm_timed_pages_target > cmm_timed_pages) { | |
167 | if (cmm_alloc_pages(1, &cmm_timed_pages, | |
168 | &cmm_timed_page_list)) | |
169 | cmm_timed_pages_target = cmm_timed_pages; | |
170 | } else if (cmm_timed_pages_target < cmm_timed_pages) { | |
171 | cmm_free_pages(1, &cmm_timed_pages, | |
db705e83 | 172 | &cmm_timed_page_list); |
1da177e4 LT |
173 | } |
174 | if (cmm_timed_pages > 0 && !timer_pending(&cmm_timer)) | |
175 | cmm_set_timer(); | |
176 | } | |
177 | return 0; | |
178 | } | |
179 | ||
db705e83 | 180 | static void cmm_kick_thread(void) |
1da177e4 | 181 | { |
1da177e4 LT |
182 | wake_up(&cmm_thread_wait); |
183 | } | |
184 | ||
db705e83 | 185 | static void cmm_set_timer(void) |
1da177e4 LT |
186 | { |
187 | if (cmm_timed_pages_target <= 0 || cmm_timeout_seconds <= 0) { | |
188 | if (timer_pending(&cmm_timer)) | |
189 | del_timer(&cmm_timer); | |
190 | return; | |
191 | } | |
192 | if (timer_pending(&cmm_timer)) { | |
193 | if (mod_timer(&cmm_timer, jiffies + cmm_timeout_seconds*HZ)) | |
194 | return; | |
195 | } | |
196 | cmm_timer.function = cmm_timer_fn; | |
197 | cmm_timer.data = 0; | |
198 | cmm_timer.expires = jiffies + cmm_timeout_seconds*HZ; | |
199 | add_timer(&cmm_timer); | |
200 | } | |
201 | ||
db705e83 | 202 | static void cmm_timer_fn(unsigned long ignored) |
1da177e4 | 203 | { |
8bc719d3 | 204 | long nr; |
1da177e4 | 205 | |
8bc719d3 MS |
206 | nr = cmm_timed_pages_target - cmm_timeout_pages; |
207 | if (nr < 0) | |
1da177e4 LT |
208 | cmm_timed_pages_target = 0; |
209 | else | |
8bc719d3 | 210 | cmm_timed_pages_target = nr; |
1da177e4 LT |
211 | cmm_kick_thread(); |
212 | cmm_set_timer(); | |
213 | } | |
214 | ||
db705e83 | 215 | static void cmm_set_pages(long nr) |
1da177e4 | 216 | { |
8bc719d3 | 217 | cmm_pages_target = nr; |
1da177e4 LT |
218 | cmm_kick_thread(); |
219 | } | |
220 | ||
db705e83 | 221 | static long cmm_get_pages(void) |
1da177e4 LT |
222 | { |
223 | return cmm_pages; | |
224 | } | |
225 | ||
db705e83 | 226 | static void cmm_add_timed_pages(long nr) |
1da177e4 | 227 | { |
8bc719d3 | 228 | cmm_timed_pages_target += nr; |
1da177e4 LT |
229 | cmm_kick_thread(); |
230 | } | |
231 | ||
db705e83 | 232 | static long cmm_get_timed_pages(void) |
1da177e4 LT |
233 | { |
234 | return cmm_timed_pages; | |
235 | } | |
236 | ||
db705e83 | 237 | static void cmm_set_timeout(long nr, long seconds) |
1da177e4 | 238 | { |
8bc719d3 | 239 | cmm_timeout_pages = nr; |
1da177e4 LT |
240 | cmm_timeout_seconds = seconds; |
241 | cmm_set_timer(); | |
242 | } | |
243 | ||
db705e83 | 244 | static int cmm_skip_blanks(char *cp, char **endp) |
1da177e4 LT |
245 | { |
246 | char *str; | |
247 | ||
db705e83 HC |
248 | for (str = cp; *str == ' ' || *str == '\t'; str++) |
249 | ; | |
1da177e4 LT |
250 | *endp = str; |
251 | return str != cp; | |
252 | } | |
253 | ||
1da177e4 LT |
254 | static struct ctl_table cmm_table[]; |
255 | ||
db705e83 HC |
256 | static int cmm_pages_handler(ctl_table *ctl, int write, void __user *buffer, |
257 | size_t *lenp, loff_t *ppos) | |
1da177e4 LT |
258 | { |
259 | char buf[16], *p; | |
8bc719d3 | 260 | long nr; |
1da177e4 LT |
261 | int len; |
262 | ||
263 | if (!*lenp || (*ppos && !write)) { | |
264 | *lenp = 0; | |
265 | return 0; | |
266 | } | |
267 | ||
268 | if (write) { | |
269 | len = *lenp; | |
270 | if (copy_from_user(buf, buffer, | |
271 | len > sizeof(buf) ? sizeof(buf) : len)) | |
272 | return -EFAULT; | |
273 | buf[sizeof(buf) - 1] = '\0'; | |
274 | cmm_skip_blanks(buf, &p); | |
8bc719d3 | 275 | nr = simple_strtoul(p, &p, 0); |
1da177e4 | 276 | if (ctl == &cmm_table[0]) |
8bc719d3 | 277 | cmm_set_pages(nr); |
1da177e4 | 278 | else |
8bc719d3 | 279 | cmm_add_timed_pages(nr); |
1da177e4 LT |
280 | } else { |
281 | if (ctl == &cmm_table[0]) | |
8bc719d3 | 282 | nr = cmm_get_pages(); |
1da177e4 | 283 | else |
8bc719d3 MS |
284 | nr = cmm_get_timed_pages(); |
285 | len = sprintf(buf, "%ld\n", nr); | |
1da177e4 LT |
286 | if (len > *lenp) |
287 | len = *lenp; | |
288 | if (copy_to_user(buffer, buf, len)) | |
289 | return -EFAULT; | |
290 | } | |
291 | *lenp = len; | |
292 | *ppos += len; | |
293 | return 0; | |
294 | } | |
295 | ||
db705e83 HC |
296 | static int cmm_timeout_handler(ctl_table *ctl, int write, void __user *buffer, |
297 | size_t *lenp, loff_t *ppos) | |
1da177e4 LT |
298 | { |
299 | char buf[64], *p; | |
8bc719d3 | 300 | long nr, seconds; |
1da177e4 LT |
301 | int len; |
302 | ||
303 | if (!*lenp || (*ppos && !write)) { | |
304 | *lenp = 0; | |
305 | return 0; | |
306 | } | |
307 | ||
308 | if (write) { | |
309 | len = *lenp; | |
310 | if (copy_from_user(buf, buffer, | |
311 | len > sizeof(buf) ? sizeof(buf) : len)) | |
312 | return -EFAULT; | |
313 | buf[sizeof(buf) - 1] = '\0'; | |
314 | cmm_skip_blanks(buf, &p); | |
8bc719d3 | 315 | nr = simple_strtoul(p, &p, 0); |
1da177e4 | 316 | cmm_skip_blanks(p, &p); |
7d5d688f | 317 | seconds = simple_strtoul(p, &p, 0); |
8bc719d3 | 318 | cmm_set_timeout(nr, seconds); |
1da177e4 LT |
319 | } else { |
320 | len = sprintf(buf, "%ld %ld\n", | |
321 | cmm_timeout_pages, cmm_timeout_seconds); | |
322 | if (len > *lenp) | |
323 | len = *lenp; | |
324 | if (copy_to_user(buffer, buf, len)) | |
325 | return -EFAULT; | |
326 | } | |
327 | *lenp = len; | |
328 | *ppos += len; | |
329 | return 0; | |
330 | } | |
331 | ||
332 | static struct ctl_table cmm_table[] = { | |
333 | { | |
1da177e4 | 334 | .procname = "cmm_pages", |
5e8b1c40 | 335 | .mode = 0644, |
6d456111 | 336 | .proc_handler = cmm_pages_handler, |
1da177e4 LT |
337 | }, |
338 | { | |
1da177e4 | 339 | .procname = "cmm_timed_pages", |
5e8b1c40 | 340 | .mode = 0644, |
6d456111 | 341 | .proc_handler = cmm_pages_handler, |
1da177e4 LT |
342 | }, |
343 | { | |
1da177e4 | 344 | .procname = "cmm_timeout", |
5e8b1c40 | 345 | .mode = 0644, |
6d456111 | 346 | .proc_handler = cmm_timeout_handler, |
1da177e4 | 347 | }, |
b05fd35d | 348 | { } |
1da177e4 LT |
349 | }; |
350 | ||
351 | static struct ctl_table cmm_dir_table[] = { | |
352 | { | |
1da177e4 LT |
353 | .procname = "vm", |
354 | .maxlen = 0, | |
355 | .mode = 0555, | |
356 | .child = cmm_table, | |
357 | }, | |
b05fd35d | 358 | { } |
1da177e4 | 359 | }; |
1da177e4 LT |
360 | |
361 | #ifdef CONFIG_CMM_IUCV | |
362 | #define SMSG_PREFIX "CMM" | |
db705e83 | 363 | static void cmm_smsg_target(const char *from, char *msg) |
1da177e4 | 364 | { |
8bc719d3 | 365 | long nr, seconds; |
1da177e4 | 366 | |
15439d74 MS |
367 | if (strlen(sender) > 0 && strcmp(from, sender) != 0) |
368 | return; | |
1da177e4 LT |
369 | if (!cmm_skip_blanks(msg + strlen(SMSG_PREFIX), &msg)) |
370 | return; | |
371 | if (strncmp(msg, "SHRINK", 6) == 0) { | |
372 | if (!cmm_skip_blanks(msg + 6, &msg)) | |
373 | return; | |
8bc719d3 | 374 | nr = simple_strtoul(msg, &msg, 0); |
1da177e4 LT |
375 | cmm_skip_blanks(msg, &msg); |
376 | if (*msg == '\0') | |
8bc719d3 | 377 | cmm_set_pages(nr); |
1da177e4 LT |
378 | } else if (strncmp(msg, "RELEASE", 7) == 0) { |
379 | if (!cmm_skip_blanks(msg + 7, &msg)) | |
380 | return; | |
8bc719d3 | 381 | nr = simple_strtoul(msg, &msg, 0); |
1da177e4 LT |
382 | cmm_skip_blanks(msg, &msg); |
383 | if (*msg == '\0') | |
8bc719d3 | 384 | cmm_add_timed_pages(nr); |
1da177e4 LT |
385 | } else if (strncmp(msg, "REUSE", 5) == 0) { |
386 | if (!cmm_skip_blanks(msg + 5, &msg)) | |
387 | return; | |
8bc719d3 | 388 | nr = simple_strtoul(msg, &msg, 0); |
1da177e4 LT |
389 | if (!cmm_skip_blanks(msg, &msg)) |
390 | return; | |
7d5d688f | 391 | seconds = simple_strtoul(msg, &msg, 0); |
1da177e4 LT |
392 | cmm_skip_blanks(msg, &msg); |
393 | if (*msg == '\0') | |
8bc719d3 | 394 | cmm_set_timeout(nr, seconds); |
1da177e4 LT |
395 | } |
396 | } | |
397 | #endif | |
398 | ||
2b67fc46 | 399 | static struct ctl_table_header *cmm_sysctl_header; |
1da177e4 | 400 | |
52b169c8 MS |
401 | static int cmm_suspend(void) |
402 | { | |
403 | cmm_suspended = 1; | |
404 | cmm_free_pages(cmm_pages, &cmm_pages, &cmm_page_list); | |
405 | cmm_free_pages(cmm_timed_pages, &cmm_timed_pages, &cmm_timed_page_list); | |
406 | return 0; | |
407 | } | |
408 | ||
409 | static int cmm_resume(void) | |
410 | { | |
411 | cmm_suspended = 0; | |
412 | cmm_kick_thread(); | |
413 | return 0; | |
414 | } | |
415 | ||
416 | static int cmm_power_event(struct notifier_block *this, | |
417 | unsigned long event, void *ptr) | |
418 | { | |
419 | switch (event) { | |
420 | case PM_POST_HIBERNATION: | |
421 | return cmm_resume(); | |
422 | case PM_HIBERNATION_PREPARE: | |
423 | return cmm_suspend(); | |
424 | default: | |
425 | return NOTIFY_DONE; | |
426 | } | |
427 | } | |
428 | ||
429 | static struct notifier_block cmm_power_notifier = { | |
430 | .notifier_call = cmm_power_event, | |
431 | }; | |
432 | ||
2e85ba51 | 433 | static int __init cmm_init(void) |
1da177e4 | 434 | { |
e8216dee HC |
435 | int rc = -ENOMEM; |
436 | ||
0b4d4147 | 437 | cmm_sysctl_header = register_sysctl_table(cmm_dir_table); |
e8216dee | 438 | if (!cmm_sysctl_header) |
52b169c8 | 439 | goto out_sysctl; |
1da177e4 | 440 | #ifdef CONFIG_CMM_IUCV |
41b42876 HB |
441 | /* convert sender to uppercase characters */ |
442 | if (sender) { | |
443 | int len = strlen(sender); | |
444 | while (len--) | |
445 | sender[len] = toupper(sender[len]); | |
a20852d2 HC |
446 | } else { |
447 | sender = cmm_default_sender; | |
41b42876 HB |
448 | } |
449 | ||
e8216dee HC |
450 | rc = smsg_register_callback(SMSG_PREFIX, cmm_smsg_target); |
451 | if (rc < 0) | |
452 | goto out_smsg; | |
1da177e4 | 453 | #endif |
e8216dee HC |
454 | rc = register_oom_notifier(&cmm_oom_nb); |
455 | if (rc < 0) | |
456 | goto out_oom_notify; | |
52b169c8 MS |
457 | rc = register_pm_notifier(&cmm_power_notifier); |
458 | if (rc) | |
459 | goto out_pm; | |
e8216dee HC |
460 | cmm_thread_ptr = kthread_run(cmm_thread, NULL, "cmmthread"); |
461 | rc = IS_ERR(cmm_thread_ptr) ? PTR_ERR(cmm_thread_ptr) : 0; | |
52b169c8 MS |
462 | if (rc) |
463 | goto out_kthread; | |
464 | return 0; | |
e8216dee | 465 | |
52b169c8 MS |
466 | out_kthread: |
467 | unregister_pm_notifier(&cmm_power_notifier); | |
468 | out_pm: | |
469 | unregister_oom_notifier(&cmm_oom_nb); | |
e8216dee HC |
470 | out_oom_notify: |
471 | #ifdef CONFIG_CMM_IUCV | |
472 | smsg_unregister_callback(SMSG_PREFIX, cmm_smsg_target); | |
473 | out_smsg: | |
474 | #endif | |
e8216dee | 475 | unregister_sysctl_table(cmm_sysctl_header); |
52b169c8 | 476 | out_sysctl: |
1ef6acf5 | 477 | del_timer_sync(&cmm_timer); |
e8216dee | 478 | return rc; |
1da177e4 | 479 | } |
db705e83 | 480 | module_init(cmm_init); |
1da177e4 | 481 | |
2e85ba51 | 482 | static void __exit cmm_exit(void) |
1da177e4 | 483 | { |
1da177e4 | 484 | unregister_sysctl_table(cmm_sysctl_header); |
1da177e4 LT |
485 | #ifdef CONFIG_CMM_IUCV |
486 | smsg_unregister_callback(SMSG_PREFIX, cmm_smsg_target); | |
487 | #endif | |
1ef6acf5 HC |
488 | unregister_pm_notifier(&cmm_power_notifier); |
489 | unregister_oom_notifier(&cmm_oom_nb); | |
490 | kthread_stop(cmm_thread_ptr); | |
491 | del_timer_sync(&cmm_timer); | |
492 | cmm_free_pages(cmm_pages, &cmm_pages, &cmm_page_list); | |
493 | cmm_free_pages(cmm_timed_pages, &cmm_timed_pages, &cmm_timed_page_list); | |
1da177e4 | 494 | } |
1da177e4 LT |
495 | module_exit(cmm_exit); |
496 | ||
1da177e4 | 497 | MODULE_LICENSE("GPL"); |