Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx
[sfrench/cifs-2.6.git] / arch / x86 / mm / pageattr-test.c
1 /*
2  * self test for change_page_attr.
3  *
4  * Clears the global bit on random pages in the direct mapping, then reverts
5  * and compares page tables forwards and afterwards.
6  */
7 #include <linux/bootmem.h>
8 #include <linux/kthread.h>
9 #include <linux/random.h>
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/mm.h>
13
14 #include <asm/cacheflush.h>
15 #include <asm/pgtable.h>
16 #include <asm/kdebug.h>
17
18 /*
19  * Only print the results of the first pass:
20  */
21 static __read_mostly int print = 1;
22
23 enum {
24         NTEST                   = 400,
25 #ifdef CONFIG_X86_64
26         LPS                     = (1 << PMD_SHIFT),
27 #elif defined(CONFIG_X86_PAE)
28         LPS                     = (1 << PMD_SHIFT),
29 #else
30         LPS                     = (1 << 22),
31 #endif
32         GPS                     = (1<<30)
33 };
34
35 struct split_state {
36         long lpg, gpg, spg, exec;
37         long min_exec, max_exec;
38 };
39
40 static int print_split(struct split_state *s)
41 {
42         long i, expected, missed = 0;
43         int err = 0;
44
45         s->lpg = s->gpg = s->spg = s->exec = 0;
46         s->min_exec = ~0UL;
47         s->max_exec = 0;
48         for (i = 0; i < max_pfn_mapped; ) {
49                 unsigned long addr = (unsigned long)__va(i << PAGE_SHIFT);
50                 unsigned int level;
51                 pte_t *pte;
52
53                 pte = lookup_address(addr, &level);
54                 if (!pte) {
55                         missed++;
56                         i++;
57                         continue;
58                 }
59
60                 if (level == PG_LEVEL_1G && sizeof(long) == 8) {
61                         s->gpg++;
62                         i += GPS/PAGE_SIZE;
63                 } else if (level == PG_LEVEL_2M) {
64                         if (!(pte_val(*pte) & _PAGE_PSE)) {
65                                 printk(KERN_ERR
66                                         "%lx level %d but not PSE %Lx\n",
67                                         addr, level, (u64)pte_val(*pte));
68                                 err = 1;
69                         }
70                         s->lpg++;
71                         i += LPS/PAGE_SIZE;
72                 } else {
73                         s->spg++;
74                         i++;
75                 }
76                 if (!(pte_val(*pte) & _PAGE_NX)) {
77                         s->exec++;
78                         if (addr < s->min_exec)
79                                 s->min_exec = addr;
80                         if (addr > s->max_exec)
81                                 s->max_exec = addr;
82                 }
83         }
84         if (print) {
85                 printk(KERN_INFO
86                         " 4k %lu large %lu gb %lu x %lu[%lx-%lx] miss %lu\n",
87                         s->spg, s->lpg, s->gpg, s->exec,
88                         s->min_exec != ~0UL ? s->min_exec : 0,
89                         s->max_exec, missed);
90         }
91
92         expected = (s->gpg*GPS + s->lpg*LPS)/PAGE_SIZE + s->spg + missed;
93         if (expected != i) {
94                 printk(KERN_ERR "CPA max_pfn_mapped %lu but expected %lu\n",
95                         max_pfn_mapped, expected);
96                 return 1;
97         }
98         return err;
99 }
100
101 static unsigned long addr[NTEST];
102 static unsigned int len[NTEST];
103
104 /* Change the global bit on random pages in the direct mapping */
105 static int pageattr_test(void)
106 {
107         struct split_state sa, sb, sc;
108         unsigned long *bm;
109         pte_t *pte, pte0;
110         int failed = 0;
111         unsigned int level;
112         int i, k;
113         int err;
114
115         if (print)
116                 printk(KERN_INFO "CPA self-test:\n");
117
118         bm = vmalloc((max_pfn_mapped + 7) / 8);
119         if (!bm) {
120                 printk(KERN_ERR "CPA Cannot vmalloc bitmap\n");
121                 return -ENOMEM;
122         }
123         memset(bm, 0, (max_pfn_mapped + 7) / 8);
124
125         failed += print_split(&sa);
126         srandom32(100);
127
128         for (i = 0; i < NTEST; i++) {
129                 unsigned long pfn = random32() % max_pfn_mapped;
130
131                 addr[i] = (unsigned long)__va(pfn << PAGE_SHIFT);
132                 len[i] = random32() % 100;
133                 len[i] = min_t(unsigned long, len[i], max_pfn_mapped - pfn - 1);
134
135                 if (len[i] == 0)
136                         len[i] = 1;
137
138                 pte = NULL;
139                 pte0 = pfn_pte(0, __pgprot(0)); /* shut gcc up */
140
141                 for (k = 0; k < len[i]; k++) {
142                         pte = lookup_address(addr[i] + k*PAGE_SIZE, &level);
143                         if (!pte || pgprot_val(pte_pgprot(*pte)) == 0 ||
144                             !(pte_val(*pte) & _PAGE_PRESENT)) {
145                                 addr[i] = 0;
146                                 break;
147                         }
148                         if (k == 0) {
149                                 pte0 = *pte;
150                         } else {
151                                 if (pgprot_val(pte_pgprot(*pte)) !=
152                                         pgprot_val(pte_pgprot(pte0))) {
153                                         len[i] = k;
154                                         break;
155                                 }
156                         }
157                         if (test_bit(pfn + k, bm)) {
158                                 len[i] = k;
159                                 break;
160                         }
161                         __set_bit(pfn + k, bm);
162                 }
163                 if (!addr[i] || !pte || !k) {
164                         addr[i] = 0;
165                         continue;
166                 }
167
168                 err = change_page_attr_clear(addr[i], len[i],
169                                                __pgprot(_PAGE_GLOBAL));
170                 if (err < 0) {
171                         printk(KERN_ERR "CPA %d failed %d\n", i, err);
172                         failed++;
173                 }
174
175                 pte = lookup_address(addr[i], &level);
176                 if (!pte || pte_global(*pte) || pte_huge(*pte)) {
177                         printk(KERN_ERR "CPA %lx: bad pte %Lx\n", addr[i],
178                                 pte ? (u64)pte_val(*pte) : 0ULL);
179                         failed++;
180                 }
181                 if (level != PG_LEVEL_4K) {
182                         printk(KERN_ERR "CPA %lx: unexpected level %d\n",
183                                 addr[i], level);
184                         failed++;
185                 }
186
187         }
188         vfree(bm);
189
190         failed += print_split(&sb);
191
192         for (i = 0; i < NTEST; i++) {
193                 if (!addr[i])
194                         continue;
195                 pte = lookup_address(addr[i], &level);
196                 if (!pte) {
197                         printk(KERN_ERR "CPA lookup of %lx failed\n", addr[i]);
198                         failed++;
199                         continue;
200                 }
201                 err = change_page_attr_set(addr[i], len[i],
202                                              __pgprot(_PAGE_GLOBAL));
203                 if (err < 0) {
204                         printk(KERN_ERR "CPA reverting failed: %d\n", err);
205                         failed++;
206                 }
207                 pte = lookup_address(addr[i], &level);
208                 if (!pte || !pte_global(*pte)) {
209                         printk(KERN_ERR "CPA %lx: bad pte after revert %Lx\n",
210                                 addr[i], pte ? (u64)pte_val(*pte) : 0ULL);
211                         failed++;
212                 }
213
214         }
215
216         failed += print_split(&sc);
217
218         if (failed) {
219                 printk(KERN_ERR "NOT PASSED. Please report.\n");
220                 WARN_ON(1);
221                 return -EINVAL;
222         } else {
223                 if (print)
224                         printk(KERN_INFO "ok.\n");
225         }
226
227         return 0;
228 }
229
230 static int do_pageattr_test(void *__unused)
231 {
232         while (!kthread_should_stop()) {
233                 schedule_timeout_interruptible(HZ*30);
234                 if (pageattr_test() < 0)
235                         break;
236                 if (print)
237                         print--;
238         }
239         return 0;
240 }
241
242 static int start_pageattr_test(void)
243 {
244         struct task_struct *p;
245
246         p = kthread_create(do_pageattr_test, NULL, "pageattr-test");
247         if (!IS_ERR(p))
248                 wake_up_process(p);
249         else
250                 WARN_ON(1);
251
252         return 0;
253 }
254
255 module_init(start_pageattr_test);