1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/kernel.h> 3 #include <linux/mm.h> 4 #include <linux/slab.h> 5 #include <linux/uaccess.h> 6 #include <linux/ktime.h> 7 #include <linux/debugfs.h> 8 #include <linux/highmem.h> 9 #include "gup_test.h" 10 11 static void put_back_pages(unsigned int cmd, struct page **pages, 12 unsigned long nr_pages, unsigned int gup_test_flags) 13 { 14 unsigned long i; 15 16 switch (cmd) { 17 case GUP_FAST_BENCHMARK: 18 case GUP_BASIC_TEST: 19 for (i = 0; i < nr_pages; i++) 20 put_page(pages[i]); 21 break; 22 23 case PIN_FAST_BENCHMARK: 24 case PIN_BASIC_TEST: 25 case PIN_LONGTERM_BENCHMARK: 26 unpin_user_pages(pages, nr_pages); 27 break; 28 case DUMP_USER_PAGES_TEST: 29 if (gup_test_flags & GUP_TEST_FLAG_DUMP_PAGES_USE_PIN) { 30 unpin_user_pages(pages, nr_pages); 31 } else { 32 for (i = 0; i < nr_pages; i++) 33 put_page(pages[i]); 34 35 } 36 break; 37 } 38 } 39 40 static void verify_dma_pinned(unsigned int cmd, struct page **pages, 41 unsigned long nr_pages) 42 { 43 unsigned long i; 44 struct folio *folio; 45 46 switch (cmd) { 47 case PIN_FAST_BENCHMARK: 48 case PIN_BASIC_TEST: 49 case PIN_LONGTERM_BENCHMARK: 50 for (i = 0; i < nr_pages; i++) { 51 folio = page_folio(pages[i]); 52 53 if (WARN(!folio_maybe_dma_pinned(folio), 54 "pages[%lu] is NOT dma-pinned\n", i)) { 55 56 dump_page(&folio->page, "gup_test failure"); 57 break; 58 } else if (cmd == PIN_LONGTERM_BENCHMARK && 59 WARN(!folio_is_longterm_pinnable(folio), 60 "pages[%lu] is NOT pinnable but pinned\n", 61 i)) { 62 dump_page(&folio->page, "gup_test failure"); 63 break; 64 } 65 } 66 break; 67 } 68 } 69 70 static void dump_pages_test(struct gup_test *gup, struct page **pages, 71 unsigned long nr_pages) 72 { 73 unsigned int index_to_dump; 74 unsigned int i; 75 76 /* 77 * Zero out any user-supplied page index that is out of range. Remember: 78 * .which_pages[] contains a 1-based set of page indices. 79 */ 80 for (i = 0; i < GUP_TEST_MAX_PAGES_TO_DUMP; i++) { 81 if (gup->which_pages[i] > nr_pages) { 82 pr_warn("ZEROING due to out of range: .which_pages[%u]: %u\n", 83 i, gup->which_pages[i]); 84 gup->which_pages[i] = 0; 85 } 86 } 87 88 for (i = 0; i < GUP_TEST_MAX_PAGES_TO_DUMP; i++) { 89 index_to_dump = gup->which_pages[i]; 90 91 if (index_to_dump) { 92 index_to_dump--; // Decode from 1-based, to 0-based 93 pr_info("---- page #%u, starting from user virt addr: 0x%llx\n", 94 index_to_dump, gup->addr); 95 dump_page(pages[index_to_dump], 96 "gup_test: dump_pages() test"); 97 } 98 } 99 } 100 101 static int __gup_test_ioctl(unsigned int cmd, 102 struct gup_test *gup) 103 { 104 ktime_t start_time, end_time; 105 unsigned long i, nr_pages, addr, next; 106 long nr; 107 struct page **pages; 108 int ret = 0; 109 bool needs_mmap_lock = 110 cmd != GUP_FAST_BENCHMARK && cmd != PIN_FAST_BENCHMARK; 111 112 if (gup->size > ULONG_MAX) 113 return -EINVAL; 114 115 nr_pages = gup->size / PAGE_SIZE; 116 pages = kvcalloc(nr_pages, sizeof(void *), GFP_KERNEL); 117 if (!pages) 118 return -ENOMEM; 119 120 if (needs_mmap_lock && mmap_read_lock_killable(current->mm)) { 121 ret = -EINTR; 122 goto free_pages; 123 } 124 125 i = 0; 126 nr = gup->nr_pages_per_call; 127 start_time = ktime_get(); 128 for (addr = gup->addr; addr < gup->addr + gup->size; addr = next) { 129 if (nr != gup->nr_pages_per_call) 130 break; 131 132 next = addr + nr * PAGE_SIZE; 133 if (next > gup->addr + gup->size) { 134 next = gup->addr + gup->size; 135 nr = (next - addr) / PAGE_SIZE; 136 } 137 138 switch (cmd) { 139 case GUP_FAST_BENCHMARK: 140 nr = get_user_pages_fast(addr, nr, gup->gup_flags, 141 pages + i); 142 break; 143 case GUP_BASIC_TEST: 144 nr = get_user_pages(addr, nr, gup->gup_flags, pages + i); 145 break; 146 case PIN_FAST_BENCHMARK: 147 nr = pin_user_pages_fast(addr, nr, gup->gup_flags, 148 pages + i); 149 break; 150 case PIN_BASIC_TEST: 151 nr = pin_user_pages(addr, nr, gup->gup_flags, pages + i); 152 break; 153 case PIN_LONGTERM_BENCHMARK: 154 nr = pin_user_pages(addr, nr, 155 gup->gup_flags | FOLL_LONGTERM, 156 pages + i); 157 break; 158 case DUMP_USER_PAGES_TEST: 159 if (gup->test_flags & GUP_TEST_FLAG_DUMP_PAGES_USE_PIN) 160 nr = pin_user_pages(addr, nr, gup->gup_flags, 161 pages + i); 162 else 163 nr = get_user_pages(addr, nr, gup->gup_flags, 164 pages + i); 165 break; 166 default: 167 ret = -EINVAL; 168 goto unlock; 169 } 170 171 if (nr <= 0) 172 break; 173 i += nr; 174 } 175 end_time = ktime_get(); 176 177 /* Shifting the meaning of nr_pages: now it is actual number pinned: */ 178 nr_pages = i; 179 180 gup->get_delta_usec = ktime_us_delta(end_time, start_time); 181 gup->size = addr - gup->addr; 182 183 /* 184 * Take an un-benchmark-timed moment to verify DMA pinned 185 * state: print a warning if any non-dma-pinned pages are found: 186 */ 187 verify_dma_pinned(cmd, pages, nr_pages); 188 189 if (cmd == DUMP_USER_PAGES_TEST) 190 dump_pages_test(gup, pages, nr_pages); 191 192 start_time = ktime_get(); 193 194 put_back_pages(cmd, pages, nr_pages, gup->test_flags); 195 196 end_time = ktime_get(); 197 gup->put_delta_usec = ktime_us_delta(end_time, start_time); 198 199 unlock: 200 if (needs_mmap_lock) 201 mmap_read_unlock(current->mm); 202 free_pages: 203 kvfree(pages); 204 return ret; 205 } 206 207 static DEFINE_MUTEX(pin_longterm_test_mutex); 208 static struct page **pin_longterm_test_pages; 209 static unsigned long pin_longterm_test_nr_pages; 210 211 static inline void pin_longterm_test_stop(void) 212 { 213 if (pin_longterm_test_pages) { 214 if (pin_longterm_test_nr_pages) 215 unpin_user_pages(pin_longterm_test_pages, 216 pin_longterm_test_nr_pages); 217 kvfree(pin_longterm_test_pages); 218 pin_longterm_test_pages = NULL; 219 pin_longterm_test_nr_pages = 0; 220 } 221 } 222 223 static inline int pin_longterm_test_start(unsigned long arg) 224 { 225 long nr_pages, cur_pages, addr, remaining_pages; 226 int gup_flags = FOLL_LONGTERM; 227 struct pin_longterm_test args; 228 struct page **pages; 229 int ret = 0; 230 bool fast; 231 232 if (pin_longterm_test_pages) 233 return -EINVAL; 234 235 if (copy_from_user(&args, (void __user *)arg, sizeof(args))) 236 return -EFAULT; 237 238 if (args.flags & 239 ~(PIN_LONGTERM_TEST_FLAG_USE_WRITE|PIN_LONGTERM_TEST_FLAG_USE_FAST)) 240 return -EINVAL; 241 if (!IS_ALIGNED(args.addr | args.size, PAGE_SIZE)) 242 return -EINVAL; 243 if (args.size > LONG_MAX) 244 return -EINVAL; 245 nr_pages = args.size / PAGE_SIZE; 246 if (!nr_pages) 247 return -EINVAL; 248 249 pages = kvcalloc(nr_pages, sizeof(void *), GFP_KERNEL); 250 if (!pages) 251 return -ENOMEM; 252 253 if (args.flags & PIN_LONGTERM_TEST_FLAG_USE_WRITE) 254 gup_flags |= FOLL_WRITE; 255 fast = !!(args.flags & PIN_LONGTERM_TEST_FLAG_USE_FAST); 256 257 if (!fast && mmap_read_lock_killable(current->mm)) { 258 kvfree(pages); 259 return -EINTR; 260 } 261 262 pin_longterm_test_pages = pages; 263 pin_longterm_test_nr_pages = 0; 264 265 while (nr_pages - pin_longterm_test_nr_pages) { 266 remaining_pages = nr_pages - pin_longterm_test_nr_pages; 267 addr = args.addr + pin_longterm_test_nr_pages * PAGE_SIZE; 268 269 if (fast) 270 cur_pages = pin_user_pages_fast(addr, remaining_pages, 271 gup_flags, pages); 272 else 273 cur_pages = pin_user_pages(addr, remaining_pages, 274 gup_flags, pages); 275 if (cur_pages < 0) { 276 pin_longterm_test_stop(); 277 ret = cur_pages; 278 break; 279 } 280 pin_longterm_test_nr_pages += cur_pages; 281 pages += cur_pages; 282 } 283 284 if (!fast) 285 mmap_read_unlock(current->mm); 286 return ret; 287 } 288 289 static inline int pin_longterm_test_read(unsigned long arg) 290 { 291 __u64 user_addr; 292 unsigned long i; 293 294 if (!pin_longterm_test_pages) 295 return -EINVAL; 296 297 if (copy_from_user(&user_addr, (void __user *)arg, sizeof(user_addr))) 298 return -EFAULT; 299 300 for (i = 0; i < pin_longterm_test_nr_pages; i++) { 301 void *addr = kmap_local_page(pin_longterm_test_pages[i]); 302 unsigned long ret; 303 304 ret = copy_to_user((void __user *)(unsigned long)user_addr, addr, 305 PAGE_SIZE); 306 kunmap_local(addr); 307 if (ret) 308 return -EFAULT; 309 user_addr += PAGE_SIZE; 310 } 311 return 0; 312 } 313 314 static long pin_longterm_test_ioctl(struct file *filep, unsigned int cmd, 315 unsigned long arg) 316 { 317 int ret = -EINVAL; 318 319 if (mutex_lock_killable(&pin_longterm_test_mutex)) 320 return -EINTR; 321 322 switch (cmd) { 323 case PIN_LONGTERM_TEST_START: 324 ret = pin_longterm_test_start(arg); 325 break; 326 case PIN_LONGTERM_TEST_STOP: 327 pin_longterm_test_stop(); 328 ret = 0; 329 break; 330 case PIN_LONGTERM_TEST_READ: 331 ret = pin_longterm_test_read(arg); 332 break; 333 } 334 335 mutex_unlock(&pin_longterm_test_mutex); 336 return ret; 337 } 338 339 static long gup_test_ioctl(struct file *filep, unsigned int cmd, 340 unsigned long arg) 341 { 342 struct gup_test gup; 343 int ret; 344 345 switch (cmd) { 346 case GUP_FAST_BENCHMARK: 347 case PIN_FAST_BENCHMARK: 348 case PIN_LONGTERM_BENCHMARK: 349 case GUP_BASIC_TEST: 350 case PIN_BASIC_TEST: 351 case DUMP_USER_PAGES_TEST: 352 break; 353 case PIN_LONGTERM_TEST_START: 354 case PIN_LONGTERM_TEST_STOP: 355 case PIN_LONGTERM_TEST_READ: 356 return pin_longterm_test_ioctl(filep, cmd, arg); 357 default: 358 return -EINVAL; 359 } 360 361 if (copy_from_user(&gup, (void __user *)arg, sizeof(gup))) 362 return -EFAULT; 363 364 ret = __gup_test_ioctl(cmd, &gup); 365 if (ret) 366 return ret; 367 368 if (copy_to_user((void __user *)arg, &gup, sizeof(gup))) 369 return -EFAULT; 370 371 return 0; 372 } 373 374 static int gup_test_release(struct inode *inode, struct file *file) 375 { 376 pin_longterm_test_stop(); 377 378 return 0; 379 } 380 381 static const struct file_operations gup_test_fops = { 382 .open = nonseekable_open, 383 .unlocked_ioctl = gup_test_ioctl, 384 .compat_ioctl = compat_ptr_ioctl, 385 .release = gup_test_release, 386 }; 387 388 static int __init gup_test_init(void) 389 { 390 debugfs_create_file_unsafe("gup_test", 0600, NULL, NULL, 391 &gup_test_fops); 392 393 return 0; 394 } 395 396 late_initcall(gup_test_init); 397