1 #include <linux/kernel.h> 2 #include <linux/mm.h> 3 #include <linux/slab.h> 4 #include <linux/uaccess.h> 5 #include <linux/ktime.h> 6 #include <linux/debugfs.h> 7 #include <linux/highmem.h> 8 #include "gup_test.h" 9 10 static void put_back_pages(unsigned int cmd, struct page **pages, 11 unsigned long nr_pages, unsigned int gup_test_flags) 12 { 13 unsigned long i; 14 15 switch (cmd) { 16 case GUP_FAST_BENCHMARK: 17 case GUP_BASIC_TEST: 18 for (i = 0; i < nr_pages; i++) 19 put_page(pages[i]); 20 break; 21 22 case PIN_FAST_BENCHMARK: 23 case PIN_BASIC_TEST: 24 case PIN_LONGTERM_BENCHMARK: 25 unpin_user_pages(pages, nr_pages); 26 break; 27 case DUMP_USER_PAGES_TEST: 28 if (gup_test_flags & GUP_TEST_FLAG_DUMP_PAGES_USE_PIN) { 29 unpin_user_pages(pages, nr_pages); 30 } else { 31 for (i = 0; i < nr_pages; i++) 32 put_page(pages[i]); 33 34 } 35 break; 36 } 37 } 38 39 static void verify_dma_pinned(unsigned int cmd, struct page **pages, 40 unsigned long nr_pages) 41 { 42 unsigned long i; 43 struct folio *folio; 44 45 switch (cmd) { 46 case PIN_FAST_BENCHMARK: 47 case PIN_BASIC_TEST: 48 case PIN_LONGTERM_BENCHMARK: 49 for (i = 0; i < nr_pages; i++) { 50 folio = page_folio(pages[i]); 51 52 if (WARN(!folio_maybe_dma_pinned(folio), 53 "pages[%lu] is NOT dma-pinned\n", i)) { 54 55 dump_page(&folio->page, "gup_test failure"); 56 break; 57 } else if (cmd == PIN_LONGTERM_BENCHMARK && 58 WARN(!folio_is_longterm_pinnable(folio), 59 "pages[%lu] is NOT pinnable but pinned\n", 60 i)) { 61 dump_page(&folio->page, "gup_test failure"); 62 break; 63 } 64 } 65 break; 66 } 67 } 68 69 static void dump_pages_test(struct gup_test *gup, struct page **pages, 70 unsigned long nr_pages) 71 { 72 unsigned int index_to_dump; 73 unsigned int i; 74 75 /* 76 * Zero out any user-supplied page index that is out of range. Remember: 77 * .which_pages[] contains a 1-based set of page indices. 78 */ 79 for (i = 0; i < GUP_TEST_MAX_PAGES_TO_DUMP; i++) { 80 if (gup->which_pages[i] > nr_pages) { 81 pr_warn("ZEROING due to out of range: .which_pages[%u]: %u\n", 82 i, gup->which_pages[i]); 83 gup->which_pages[i] = 0; 84 } 85 } 86 87 for (i = 0; i < GUP_TEST_MAX_PAGES_TO_DUMP; i++) { 88 index_to_dump = gup->which_pages[i]; 89 90 if (index_to_dump) { 91 index_to_dump--; // Decode from 1-based, to 0-based 92 pr_info("---- page #%u, starting from user virt addr: 0x%llx\n", 93 index_to_dump, gup->addr); 94 dump_page(pages[index_to_dump], 95 "gup_test: dump_pages() test"); 96 } 97 } 98 } 99 100 static int __gup_test_ioctl(unsigned int cmd, 101 struct gup_test *gup) 102 { 103 ktime_t start_time, end_time; 104 unsigned long i, nr_pages, addr, next; 105 long nr; 106 struct page **pages; 107 int ret = 0; 108 bool needs_mmap_lock = 109 cmd != GUP_FAST_BENCHMARK && cmd != PIN_FAST_BENCHMARK; 110 111 if (gup->size > ULONG_MAX) 112 return -EINVAL; 113 114 nr_pages = gup->size / PAGE_SIZE; 115 pages = kvcalloc(nr_pages, sizeof(void *), GFP_KERNEL); 116 if (!pages) 117 return -ENOMEM; 118 119 if (needs_mmap_lock && mmap_read_lock_killable(current->mm)) { 120 ret = -EINTR; 121 goto free_pages; 122 } 123 124 i = 0; 125 nr = gup->nr_pages_per_call; 126 start_time = ktime_get(); 127 for (addr = gup->addr; addr < gup->addr + gup->size; addr = next) { 128 if (nr != gup->nr_pages_per_call) 129 break; 130 131 next = addr + nr * PAGE_SIZE; 132 if (next > gup->addr + gup->size) { 133 next = gup->addr + gup->size; 134 nr = (next - addr) / PAGE_SIZE; 135 } 136 137 switch (cmd) { 138 case GUP_FAST_BENCHMARK: 139 nr = get_user_pages_fast(addr, nr, gup->gup_flags, 140 pages + i); 141 break; 142 case GUP_BASIC_TEST: 143 nr = get_user_pages(addr, nr, gup->gup_flags, pages + i); 144 break; 145 case PIN_FAST_BENCHMARK: 146 nr = pin_user_pages_fast(addr, nr, gup->gup_flags, 147 pages + i); 148 break; 149 case PIN_BASIC_TEST: 150 nr = pin_user_pages(addr, nr, gup->gup_flags, pages + i); 151 break; 152 case PIN_LONGTERM_BENCHMARK: 153 nr = pin_user_pages(addr, nr, 154 gup->gup_flags | FOLL_LONGTERM, 155 pages + i); 156 break; 157 case DUMP_USER_PAGES_TEST: 158 if (gup->test_flags & GUP_TEST_FLAG_DUMP_PAGES_USE_PIN) 159 nr = pin_user_pages(addr, nr, gup->gup_flags, 160 pages + i); 161 else 162 nr = get_user_pages(addr, nr, gup->gup_flags, 163 pages + i); 164 break; 165 default: 166 ret = -EINVAL; 167 goto unlock; 168 } 169 170 if (nr <= 0) 171 break; 172 i += nr; 173 } 174 end_time = ktime_get(); 175 176 /* Shifting the meaning of nr_pages: now it is actual number pinned: */ 177 nr_pages = i; 178 179 gup->get_delta_usec = ktime_us_delta(end_time, start_time); 180 gup->size = addr - gup->addr; 181 182 /* 183 * Take an un-benchmark-timed moment to verify DMA pinned 184 * state: print a warning if any non-dma-pinned pages are found: 185 */ 186 verify_dma_pinned(cmd, pages, nr_pages); 187 188 if (cmd == DUMP_USER_PAGES_TEST) 189 dump_pages_test(gup, pages, nr_pages); 190 191 start_time = ktime_get(); 192 193 put_back_pages(cmd, pages, nr_pages, gup->test_flags); 194 195 end_time = ktime_get(); 196 gup->put_delta_usec = ktime_us_delta(end_time, start_time); 197 198 unlock: 199 if (needs_mmap_lock) 200 mmap_read_unlock(current->mm); 201 free_pages: 202 kvfree(pages); 203 return ret; 204 } 205 206 static DEFINE_MUTEX(pin_longterm_test_mutex); 207 static struct page **pin_longterm_test_pages; 208 static unsigned long pin_longterm_test_nr_pages; 209 210 static inline void pin_longterm_test_stop(void) 211 { 212 if (pin_longterm_test_pages) { 213 if (pin_longterm_test_nr_pages) 214 unpin_user_pages(pin_longterm_test_pages, 215 pin_longterm_test_nr_pages); 216 kvfree(pin_longterm_test_pages); 217 pin_longterm_test_pages = NULL; 218 pin_longterm_test_nr_pages = 0; 219 } 220 } 221 222 static inline int pin_longterm_test_start(unsigned long arg) 223 { 224 long nr_pages, cur_pages, addr, remaining_pages; 225 int gup_flags = FOLL_LONGTERM; 226 struct pin_longterm_test args; 227 struct page **pages; 228 int ret = 0; 229 bool fast; 230 231 if (pin_longterm_test_pages) 232 return -EINVAL; 233 234 if (copy_from_user(&args, (void __user *)arg, sizeof(args))) 235 return -EFAULT; 236 237 if (args.flags & 238 ~(PIN_LONGTERM_TEST_FLAG_USE_WRITE|PIN_LONGTERM_TEST_FLAG_USE_FAST)) 239 return -EINVAL; 240 if (!IS_ALIGNED(args.addr | args.size, PAGE_SIZE)) 241 return -EINVAL; 242 if (args.size > LONG_MAX) 243 return -EINVAL; 244 nr_pages = args.size / PAGE_SIZE; 245 if (!nr_pages) 246 return -EINVAL; 247 248 pages = kvcalloc(nr_pages, sizeof(void *), GFP_KERNEL); 249 if (!pages) 250 return -ENOMEM; 251 252 if (args.flags & PIN_LONGTERM_TEST_FLAG_USE_WRITE) 253 gup_flags |= FOLL_WRITE; 254 fast = !!(args.flags & PIN_LONGTERM_TEST_FLAG_USE_FAST); 255 256 if (!fast && mmap_read_lock_killable(current->mm)) { 257 kvfree(pages); 258 return -EINTR; 259 } 260 261 pin_longterm_test_pages = pages; 262 pin_longterm_test_nr_pages = 0; 263 264 while (nr_pages - pin_longterm_test_nr_pages) { 265 remaining_pages = nr_pages - pin_longterm_test_nr_pages; 266 addr = args.addr + pin_longterm_test_nr_pages * PAGE_SIZE; 267 268 if (fast) 269 cur_pages = pin_user_pages_fast(addr, remaining_pages, 270 gup_flags, pages); 271 else 272 cur_pages = pin_user_pages(addr, remaining_pages, 273 gup_flags, pages); 274 if (cur_pages < 0) { 275 pin_longterm_test_stop(); 276 ret = cur_pages; 277 break; 278 } 279 pin_longterm_test_nr_pages += cur_pages; 280 pages += cur_pages; 281 } 282 283 if (!fast) 284 mmap_read_unlock(current->mm); 285 return ret; 286 } 287 288 static inline int pin_longterm_test_read(unsigned long arg) 289 { 290 __u64 user_addr; 291 unsigned long i; 292 293 if (!pin_longterm_test_pages) 294 return -EINVAL; 295 296 if (copy_from_user(&user_addr, (void __user *)arg, sizeof(user_addr))) 297 return -EFAULT; 298 299 for (i = 0; i < pin_longterm_test_nr_pages; i++) { 300 void *addr = kmap_local_page(pin_longterm_test_pages[i]); 301 unsigned long ret; 302 303 ret = copy_to_user((void __user *)(unsigned long)user_addr, addr, 304 PAGE_SIZE); 305 kunmap_local(addr); 306 if (ret) 307 return -EFAULT; 308 user_addr += PAGE_SIZE; 309 } 310 return 0; 311 } 312 313 static long pin_longterm_test_ioctl(struct file *filep, unsigned int cmd, 314 unsigned long arg) 315 { 316 int ret = -EINVAL; 317 318 if (mutex_lock_killable(&pin_longterm_test_mutex)) 319 return -EINTR; 320 321 switch (cmd) { 322 case PIN_LONGTERM_TEST_START: 323 ret = pin_longterm_test_start(arg); 324 break; 325 case PIN_LONGTERM_TEST_STOP: 326 pin_longterm_test_stop(); 327 ret = 0; 328 break; 329 case PIN_LONGTERM_TEST_READ: 330 ret = pin_longterm_test_read(arg); 331 break; 332 } 333 334 mutex_unlock(&pin_longterm_test_mutex); 335 return ret; 336 } 337 338 static long gup_test_ioctl(struct file *filep, unsigned int cmd, 339 unsigned long arg) 340 { 341 struct gup_test gup; 342 int ret; 343 344 switch (cmd) { 345 case GUP_FAST_BENCHMARK: 346 case PIN_FAST_BENCHMARK: 347 case PIN_LONGTERM_BENCHMARK: 348 case GUP_BASIC_TEST: 349 case PIN_BASIC_TEST: 350 case DUMP_USER_PAGES_TEST: 351 break; 352 case PIN_LONGTERM_TEST_START: 353 case PIN_LONGTERM_TEST_STOP: 354 case PIN_LONGTERM_TEST_READ: 355 return pin_longterm_test_ioctl(filep, cmd, arg); 356 default: 357 return -EINVAL; 358 } 359 360 if (copy_from_user(&gup, (void __user *)arg, sizeof(gup))) 361 return -EFAULT; 362 363 ret = __gup_test_ioctl(cmd, &gup); 364 if (ret) 365 return ret; 366 367 if (copy_to_user((void __user *)arg, &gup, sizeof(gup))) 368 return -EFAULT; 369 370 return 0; 371 } 372 373 static int gup_test_release(struct inode *inode, struct file *file) 374 { 375 pin_longterm_test_stop(); 376 377 return 0; 378 } 379 380 static const struct file_operations gup_test_fops = { 381 .open = nonseekable_open, 382 .unlocked_ioctl = gup_test_ioctl, 383 .compat_ioctl = compat_ptr_ioctl, 384 .release = gup_test_release, 385 }; 386 387 static int __init gup_test_init(void) 388 { 389 debugfs_create_file_unsafe("gup_test", 0600, NULL, NULL, 390 &gup_test_fops); 391 392 return 0; 393 } 394 395 late_initcall(gup_test_init); 396