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 "gup_test.h" 8 9 static void put_back_pages(unsigned int cmd, struct page **pages, 10 unsigned long nr_pages, unsigned int gup_test_flags) 11 { 12 unsigned long i; 13 14 switch (cmd) { 15 case GUP_FAST_BENCHMARK: 16 case GUP_BASIC_TEST: 17 for (i = 0; i < nr_pages; i++) 18 put_page(pages[i]); 19 break; 20 21 case PIN_FAST_BENCHMARK: 22 case PIN_BASIC_TEST: 23 case PIN_LONGTERM_BENCHMARK: 24 unpin_user_pages(pages, nr_pages); 25 break; 26 case DUMP_USER_PAGES_TEST: 27 if (gup_test_flags & GUP_TEST_FLAG_DUMP_PAGES_USE_PIN) { 28 unpin_user_pages(pages, nr_pages); 29 } else { 30 for (i = 0; i < nr_pages; i++) 31 put_page(pages[i]); 32 33 } 34 break; 35 } 36 } 37 38 static void verify_dma_pinned(unsigned int cmd, struct page **pages, 39 unsigned long nr_pages) 40 { 41 unsigned long i; 42 struct page *page; 43 44 switch (cmd) { 45 case PIN_FAST_BENCHMARK: 46 case PIN_BASIC_TEST: 47 case PIN_LONGTERM_BENCHMARK: 48 for (i = 0; i < nr_pages; i++) { 49 page = pages[i]; 50 if (WARN(!page_maybe_dma_pinned(page), 51 "pages[%lu] is NOT dma-pinned\n", i)) { 52 53 dump_page(page, "gup_test failure"); 54 break; 55 } else if (cmd == PIN_LONGTERM_BENCHMARK && 56 WARN(!is_pinnable_page(page), 57 "pages[%lu] is NOT pinnable but pinned\n", 58 i)) { 59 dump_page(page, "gup_test failure"); 60 break; 61 } 62 } 63 break; 64 } 65 } 66 67 static void dump_pages_test(struct gup_test *gup, struct page **pages, 68 unsigned long nr_pages) 69 { 70 unsigned int index_to_dump; 71 unsigned int i; 72 73 /* 74 * Zero out any user-supplied page index that is out of range. Remember: 75 * .which_pages[] contains a 1-based set of page indices. 76 */ 77 for (i = 0; i < GUP_TEST_MAX_PAGES_TO_DUMP; i++) { 78 if (gup->which_pages[i] > nr_pages) { 79 pr_warn("ZEROING due to out of range: .which_pages[%u]: %u\n", 80 i, gup->which_pages[i]); 81 gup->which_pages[i] = 0; 82 } 83 } 84 85 for (i = 0; i < GUP_TEST_MAX_PAGES_TO_DUMP; i++) { 86 index_to_dump = gup->which_pages[i]; 87 88 if (index_to_dump) { 89 index_to_dump--; // Decode from 1-based, to 0-based 90 pr_info("---- page #%u, starting from user virt addr: 0x%llx\n", 91 index_to_dump, gup->addr); 92 dump_page(pages[index_to_dump], 93 "gup_test: dump_pages() test"); 94 } 95 } 96 } 97 98 static int __gup_test_ioctl(unsigned int cmd, 99 struct gup_test *gup) 100 { 101 ktime_t start_time, end_time; 102 unsigned long i, nr_pages, addr, next; 103 long nr; 104 struct page **pages; 105 int ret = 0; 106 bool needs_mmap_lock = 107 cmd != GUP_FAST_BENCHMARK && cmd != PIN_FAST_BENCHMARK; 108 109 if (gup->size > ULONG_MAX) 110 return -EINVAL; 111 112 nr_pages = gup->size / PAGE_SIZE; 113 pages = kvcalloc(nr_pages, sizeof(void *), GFP_KERNEL); 114 if (!pages) 115 return -ENOMEM; 116 117 if (needs_mmap_lock && mmap_read_lock_killable(current->mm)) { 118 ret = -EINTR; 119 goto free_pages; 120 } 121 122 i = 0; 123 nr = gup->nr_pages_per_call; 124 start_time = ktime_get(); 125 for (addr = gup->addr; addr < gup->addr + gup->size; addr = next) { 126 if (nr != gup->nr_pages_per_call) 127 break; 128 129 next = addr + nr * PAGE_SIZE; 130 if (next > gup->addr + gup->size) { 131 next = gup->addr + gup->size; 132 nr = (next - addr) / PAGE_SIZE; 133 } 134 135 switch (cmd) { 136 case GUP_FAST_BENCHMARK: 137 nr = get_user_pages_fast(addr, nr, gup->gup_flags, 138 pages + i); 139 break; 140 case GUP_BASIC_TEST: 141 nr = get_user_pages(addr, nr, gup->gup_flags, pages + i, 142 NULL); 143 break; 144 case PIN_FAST_BENCHMARK: 145 nr = pin_user_pages_fast(addr, nr, gup->gup_flags, 146 pages + i); 147 break; 148 case PIN_BASIC_TEST: 149 nr = pin_user_pages(addr, nr, gup->gup_flags, pages + i, 150 NULL); 151 break; 152 case PIN_LONGTERM_BENCHMARK: 153 nr = pin_user_pages(addr, nr, 154 gup->gup_flags | FOLL_LONGTERM, 155 pages + i, NULL); 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, NULL); 161 else 162 nr = get_user_pages(addr, nr, gup->gup_flags, 163 pages + i, NULL); 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 long gup_test_ioctl(struct file *filep, unsigned int cmd, 207 unsigned long arg) 208 { 209 struct gup_test gup; 210 int ret; 211 212 switch (cmd) { 213 case GUP_FAST_BENCHMARK: 214 case PIN_FAST_BENCHMARK: 215 case PIN_LONGTERM_BENCHMARK: 216 case GUP_BASIC_TEST: 217 case PIN_BASIC_TEST: 218 case DUMP_USER_PAGES_TEST: 219 break; 220 default: 221 return -EINVAL; 222 } 223 224 if (copy_from_user(&gup, (void __user *)arg, sizeof(gup))) 225 return -EFAULT; 226 227 ret = __gup_test_ioctl(cmd, &gup); 228 if (ret) 229 return ret; 230 231 if (copy_to_user((void __user *)arg, &gup, sizeof(gup))) 232 return -EFAULT; 233 234 return 0; 235 } 236 237 static const struct file_operations gup_test_fops = { 238 .open = nonseekable_open, 239 .unlocked_ioctl = gup_test_ioctl, 240 }; 241 242 static int __init gup_test_init(void) 243 { 244 debugfs_create_file_unsafe("gup_test", 0600, NULL, NULL, 245 &gup_test_fops); 246 247 return 0; 248 } 249 250 late_initcall(gup_test_init); 251