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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/s390/mm/cmm.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/s390/mm/cmm.c')
-rw-r--r--arch/s390/mm/cmm.c443
1 files changed, 443 insertions, 0 deletions
diff --git a/arch/s390/mm/cmm.c b/arch/s390/mm/cmm.c
new file mode 100644
index 000000000000..d30cdb4248a9
--- /dev/null
+++ b/arch/s390/mm/cmm.c
@@ -0,0 +1,443 @@
1/*
2 * arch/s390/mm/cmm.c
3 *
4 * S390 version
5 * Copyright (C) 2003 IBM Deutschland Entwicklung GmbH, IBM Corporation
6 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
7 *
8 * Collaborative memory management interface.
9 */
10
11#include <linux/config.h>
12#include <linux/errno.h>
13#include <linux/fs.h>
14#include <linux/init.h>
15#include <linux/module.h>
16#include <linux/sched.h>
17#include <linux/sysctl.h>
18#include <linux/ctype.h>
19
20#include <asm/pgalloc.h>
21#include <asm/uaccess.h>
22
23#include "../../../drivers/s390/net/smsgiucv.h"
24
25#define CMM_NR_PAGES ((PAGE_SIZE / sizeof(unsigned long)) - 2)
26
27struct cmm_page_array {
28 struct cmm_page_array *next;
29 unsigned long index;
30 unsigned long pages[CMM_NR_PAGES];
31};
32
33static long cmm_pages = 0;
34static long cmm_timed_pages = 0;
35static volatile long cmm_pages_target = 0;
36static volatile long cmm_timed_pages_target = 0;
37static long cmm_timeout_pages = 0;
38static long cmm_timeout_seconds = 0;
39
40static struct cmm_page_array *cmm_page_list = 0;
41static struct cmm_page_array *cmm_timed_page_list = 0;
42
43static unsigned long cmm_thread_active = 0;
44static struct work_struct cmm_thread_starter;
45static wait_queue_head_t cmm_thread_wait;
46static struct timer_list cmm_timer;
47
48static void cmm_timer_fn(unsigned long);
49static void cmm_set_timer(void);
50
51static long
52cmm_strtoul(const char *cp, char **endp)
53{
54 unsigned int base = 10;
55
56 if (*cp == '0') {
57 base = 8;
58 cp++;
59 if ((*cp == 'x' || *cp == 'X') && isxdigit(cp[1])) {
60 base = 16;
61 cp++;
62 }
63 }
64 return simple_strtoul(cp, endp, base);
65}
66
67static long
68cmm_alloc_pages(long pages, long *counter, struct cmm_page_array **list)
69{
70 struct cmm_page_array *pa;
71 unsigned long page;
72
73 pa = *list;
74 while (pages) {
75 page = __get_free_page(GFP_NOIO);
76 if (!page)
77 break;
78 if (!pa || pa->index >= CMM_NR_PAGES) {
79 /* Need a new page for the page list. */
80 pa = (struct cmm_page_array *)
81 __get_free_page(GFP_NOIO);
82 if (!pa) {
83 free_page(page);
84 break;
85 }
86 pa->next = *list;
87 pa->index = 0;
88 *list = pa;
89 }
90 diag10(page);
91 pa->pages[pa->index++] = page;
92 (*counter)++;
93 pages--;
94 }
95 return pages;
96}
97
98static void
99cmm_free_pages(long pages, long *counter, struct cmm_page_array **list)
100{
101 struct cmm_page_array *pa;
102 unsigned long page;
103
104 pa = *list;
105 while (pages) {
106 if (!pa || pa->index <= 0)
107 break;
108 page = pa->pages[--pa->index];
109 if (pa->index == 0) {
110 pa = pa->next;
111 free_page((unsigned long) *list);
112 *list = pa;
113 }
114 free_page(page);
115 (*counter)--;
116 pages--;
117 }
118}
119
120static int
121cmm_thread(void *dummy)
122{
123 int rc;
124
125 daemonize("cmmthread");
126 while (1) {
127 rc = wait_event_interruptible(cmm_thread_wait,
128 (cmm_pages != cmm_pages_target ||
129 cmm_timed_pages != cmm_timed_pages_target));
130 if (rc == -ERESTARTSYS) {
131 /* Got kill signal. End thread. */
132 clear_bit(0, &cmm_thread_active);
133 cmm_pages_target = cmm_pages;
134 cmm_timed_pages_target = cmm_timed_pages;
135 break;
136 }
137 if (cmm_pages_target > cmm_pages) {
138 if (cmm_alloc_pages(1, &cmm_pages, &cmm_page_list))
139 cmm_pages_target = cmm_pages;
140 } else if (cmm_pages_target < cmm_pages) {
141 cmm_free_pages(1, &cmm_pages, &cmm_page_list);
142 }
143 if (cmm_timed_pages_target > cmm_timed_pages) {
144 if (cmm_alloc_pages(1, &cmm_timed_pages,
145 &cmm_timed_page_list))
146 cmm_timed_pages_target = cmm_timed_pages;
147 } else if (cmm_timed_pages_target < cmm_timed_pages) {
148 cmm_free_pages(1, &cmm_timed_pages,
149 &cmm_timed_page_list);
150 }
151 if (cmm_timed_pages > 0 && !timer_pending(&cmm_timer))
152 cmm_set_timer();
153 }
154 return 0;
155}
156
157static void
158cmm_start_thread(void)
159{
160 kernel_thread(cmm_thread, 0, 0);
161}
162
163static void
164cmm_kick_thread(void)
165{
166 if (!test_and_set_bit(0, &cmm_thread_active))
167 schedule_work(&cmm_thread_starter);
168 wake_up(&cmm_thread_wait);
169}
170
171static void
172cmm_set_timer(void)
173{
174 if (cmm_timed_pages_target <= 0 || cmm_timeout_seconds <= 0) {
175 if (timer_pending(&cmm_timer))
176 del_timer(&cmm_timer);
177 return;
178 }
179 if (timer_pending(&cmm_timer)) {
180 if (mod_timer(&cmm_timer, jiffies + cmm_timeout_seconds*HZ))
181 return;
182 }
183 cmm_timer.function = cmm_timer_fn;
184 cmm_timer.data = 0;
185 cmm_timer.expires = jiffies + cmm_timeout_seconds*HZ;
186 add_timer(&cmm_timer);
187}
188
189static void
190cmm_timer_fn(unsigned long ignored)
191{
192 long pages;
193
194 pages = cmm_timed_pages_target - cmm_timeout_pages;
195 if (pages < 0)
196 cmm_timed_pages_target = 0;
197 else
198 cmm_timed_pages_target = pages;
199 cmm_kick_thread();
200 cmm_set_timer();
201}
202
203void
204cmm_set_pages(long pages)
205{
206 cmm_pages_target = pages;
207 cmm_kick_thread();
208}
209
210long
211cmm_get_pages(void)
212{
213 return cmm_pages;
214}
215
216void
217cmm_add_timed_pages(long pages)
218{
219 cmm_timed_pages_target += pages;
220 cmm_kick_thread();
221}
222
223long
224cmm_get_timed_pages(void)
225{
226 return cmm_timed_pages;
227}
228
229void
230cmm_set_timeout(long pages, long seconds)
231{
232 cmm_timeout_pages = pages;
233 cmm_timeout_seconds = seconds;
234 cmm_set_timer();
235}
236
237static inline int
238cmm_skip_blanks(char *cp, char **endp)
239{
240 char *str;
241
242 for (str = cp; *str == ' ' || *str == '\t'; str++);
243 *endp = str;
244 return str != cp;
245}
246
247#ifdef CONFIG_CMM_PROC
248/* These will someday get removed. */
249#define VM_CMM_PAGES 1111
250#define VM_CMM_TIMED_PAGES 1112
251#define VM_CMM_TIMEOUT 1113
252
253static struct ctl_table cmm_table[];
254
255static int
256cmm_pages_handler(ctl_table *ctl, int write, struct file *filp,
257 void *buffer, size_t *lenp, loff_t *ppos)
258{
259 char buf[16], *p;
260 long pages;
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);
275 pages = cmm_strtoul(p, &p);
276 if (ctl == &cmm_table[0])
277 cmm_set_pages(pages);
278 else
279 cmm_add_timed_pages(pages);
280 } else {
281 if (ctl == &cmm_table[0])
282 pages = cmm_get_pages();
283 else
284 pages = cmm_get_timed_pages();
285 len = sprintf(buf, "%ld\n", pages);
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
296static int
297cmm_timeout_handler(ctl_table *ctl, int write, struct file *filp,
298 void *buffer, size_t *lenp, loff_t *ppos)
299{
300 char buf[64], *p;
301 long pages, seconds;
302 int len;
303
304 if (!*lenp || (*ppos && !write)) {
305 *lenp = 0;
306 return 0;
307 }
308
309 if (write) {
310 len = *lenp;
311 if (copy_from_user(buf, buffer,
312 len > sizeof(buf) ? sizeof(buf) : len))
313 return -EFAULT;
314 buf[sizeof(buf) - 1] = '\0';
315 cmm_skip_blanks(buf, &p);
316 pages = cmm_strtoul(p, &p);
317 cmm_skip_blanks(p, &p);
318 seconds = cmm_strtoul(p, &p);
319 cmm_set_timeout(pages, seconds);
320 } else {
321 len = sprintf(buf, "%ld %ld\n",
322 cmm_timeout_pages, cmm_timeout_seconds);
323 if (len > *lenp)
324 len = *lenp;
325 if (copy_to_user(buffer, buf, len))
326 return -EFAULT;
327 }
328 *lenp = len;
329 *ppos += len;
330 return 0;
331}
332
333static struct ctl_table cmm_table[] = {
334 {
335 .ctl_name = VM_CMM_PAGES,
336 .procname = "cmm_pages",
337 .mode = 0600,
338 .proc_handler = &cmm_pages_handler,
339 },
340 {
341 .ctl_name = VM_CMM_TIMED_PAGES,
342 .procname = "cmm_timed_pages",
343 .mode = 0600,
344 .proc_handler = &cmm_pages_handler,
345 },
346 {
347 .ctl_name = VM_CMM_TIMEOUT,
348 .procname = "cmm_timeout",
349 .mode = 0600,
350 .proc_handler = &cmm_timeout_handler,
351 },
352 { .ctl_name = 0 }
353};
354
355static struct ctl_table cmm_dir_table[] = {
356 {
357 .ctl_name = CTL_VM,
358 .procname = "vm",
359 .maxlen = 0,
360 .mode = 0555,
361 .child = cmm_table,
362 },
363 { .ctl_name = 0 }
364};
365#endif
366
367#ifdef CONFIG_CMM_IUCV
368#define SMSG_PREFIX "CMM"
369static void
370cmm_smsg_target(char *msg)
371{
372 long pages, seconds;
373
374 if (!cmm_skip_blanks(msg + strlen(SMSG_PREFIX), &msg))
375 return;
376 if (strncmp(msg, "SHRINK", 6) == 0) {
377 if (!cmm_skip_blanks(msg + 6, &msg))
378 return;
379 pages = cmm_strtoul(msg, &msg);
380 cmm_skip_blanks(msg, &msg);
381 if (*msg == '\0')
382 cmm_set_pages(pages);
383 } else if (strncmp(msg, "RELEASE", 7) == 0) {
384 if (!cmm_skip_blanks(msg + 7, &msg))
385 return;
386 pages = cmm_strtoul(msg, &msg);
387 cmm_skip_blanks(msg, &msg);
388 if (*msg == '\0')
389 cmm_add_timed_pages(pages);
390 } else if (strncmp(msg, "REUSE", 5) == 0) {
391 if (!cmm_skip_blanks(msg + 5, &msg))
392 return;
393 pages = cmm_strtoul(msg, &msg);
394 if (!cmm_skip_blanks(msg, &msg))
395 return;
396 seconds = cmm_strtoul(msg, &msg);
397 cmm_skip_blanks(msg, &msg);
398 if (*msg == '\0')
399 cmm_set_timeout(pages, seconds);
400 }
401}
402#endif
403
404struct ctl_table_header *cmm_sysctl_header;
405
406static int
407cmm_init (void)
408{
409#ifdef CONFIG_CMM_PROC
410 cmm_sysctl_header = register_sysctl_table(cmm_dir_table, 1);
411#endif
412#ifdef CONFIG_CMM_IUCV
413 smsg_register_callback(SMSG_PREFIX, cmm_smsg_target);
414#endif
415 INIT_WORK(&cmm_thread_starter, (void *) cmm_start_thread, 0);
416 init_waitqueue_head(&cmm_thread_wait);
417 init_timer(&cmm_timer);
418 return 0;
419}
420
421static void
422cmm_exit(void)
423{
424 cmm_free_pages(cmm_pages, &cmm_pages, &cmm_page_list);
425 cmm_free_pages(cmm_timed_pages, &cmm_timed_pages, &cmm_timed_page_list);
426#ifdef CONFIG_CMM_PROC
427 unregister_sysctl_table(cmm_sysctl_header);
428#endif
429#ifdef CONFIG_CMM_IUCV
430 smsg_unregister_callback(SMSG_PREFIX, cmm_smsg_target);
431#endif
432}
433
434module_init(cmm_init);
435module_exit(cmm_exit);
436
437EXPORT_SYMBOL(cmm_set_pages);
438EXPORT_SYMBOL(cmm_get_pages);
439EXPORT_SYMBOL(cmm_add_timed_pages);
440EXPORT_SYMBOL(cmm_get_timed_pages);
441EXPORT_SYMBOL(cmm_set_timeout);
442
443MODULE_LICENSE("GPL");