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1/*2 * Copyright © 2016 Intel Corporation3 *4 * Permission is hereby granted, free of charge, to any person obtaining a5 * copy of this software and associated documentation files (the "Software"),6 * to deal in the Software without restriction, including without limitation7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,8 * and/or sell copies of the Software, and to permit persons to whom the9 * Software is furnished to do so, subject to the following conditions:10 *11 * The above copyright notice and this permission notice (including the next12 * paragraph) shall be included in all copies or substantial portions of the13 * Software.14 *15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS21 * IN THE SOFTWARE.22 */23 24#include <linux/prime_numbers.h>25#include <linux/random.h>26 27#include "i915_selftest.h"28#include "i915_utils.h"29 30#define PFN_BIAS (1 << 10)31 32struct pfn_table {33 struct sg_table st;34 unsigned long start, end;35};36 37typedef unsigned int (*npages_fn_t)(unsigned long n,38 unsigned long count,39 struct rnd_state *rnd);40 41static noinline int expect_pfn_sg(struct pfn_table *pt,42 npages_fn_t npages_fn,43 struct rnd_state *rnd,44 const char *who,45 unsigned long timeout)46{47 struct scatterlist *sg;48 unsigned long pfn, n;49 50 pfn = pt->start;51 for_each_sg(pt->st.sgl, sg, pt->st.nents, n) {52 struct page *page = sg_page(sg);53 unsigned int npages = npages_fn(n, pt->st.nents, rnd);54 55 if (page_to_pfn(page) != pfn) {56 pr_err("%s: %s left pages out of order, expected pfn %lu, found pfn %lu (using for_each_sg)\n",57 __func__, who, pfn, page_to_pfn(page));58 return -EINVAL;59 }60 61 if (sg->length != npages * PAGE_SIZE) {62 pr_err("%s: %s copied wrong sg length, expected size %lu, found %u (using for_each_sg)\n",63 __func__, who, npages * PAGE_SIZE, sg->length);64 return -EINVAL;65 }66 67 if (igt_timeout(timeout, "%s timed out\n", who))68 return -EINTR;69 70 pfn += npages;71 }72 if (pfn != pt->end) {73 pr_err("%s: %s finished on wrong pfn, expected %lu, found %lu\n",74 __func__, who, pt->end, pfn);75 return -EINVAL;76 }77 78 return 0;79}80 81static noinline int expect_pfn_sg_page_iter(struct pfn_table *pt,82 const char *who,83 unsigned long timeout)84{85 struct sg_page_iter sgiter;86 unsigned long pfn;87 88 pfn = pt->start;89 for_each_sg_page(pt->st.sgl, &sgiter, pt->st.nents, 0) {90 struct page *page = sg_page_iter_page(&sgiter);91 92 if (page != pfn_to_page(pfn)) {93 pr_err("%s: %s left pages out of order, expected pfn %lu, found pfn %lu (using for_each_sg_page)\n",94 __func__, who, pfn, page_to_pfn(page));95 return -EINVAL;96 }97 98 if (igt_timeout(timeout, "%s timed out\n", who))99 return -EINTR;100 101 pfn++;102 }103 if (pfn != pt->end) {104 pr_err("%s: %s finished on wrong pfn, expected %lu, found %lu\n",105 __func__, who, pt->end, pfn);106 return -EINVAL;107 }108 109 return 0;110}111 112static noinline int expect_pfn_sgtiter(struct pfn_table *pt,113 const char *who,114 unsigned long timeout)115{116 struct sgt_iter sgt;117 struct page *page;118 unsigned long pfn;119 120 pfn = pt->start;121 for_each_sgt_page(page, sgt, &pt->st) {122 if (page != pfn_to_page(pfn)) {123 pr_err("%s: %s left pages out of order, expected pfn %lu, found pfn %lu (using for_each_sgt_page)\n",124 __func__, who, pfn, page_to_pfn(page));125 return -EINVAL;126 }127 128 if (igt_timeout(timeout, "%s timed out\n", who))129 return -EINTR;130 131 pfn++;132 }133 if (pfn != pt->end) {134 pr_err("%s: %s finished on wrong pfn, expected %lu, found %lu\n",135 __func__, who, pt->end, pfn);136 return -EINVAL;137 }138 139 return 0;140}141 142static int expect_pfn_sgtable(struct pfn_table *pt,143 npages_fn_t npages_fn,144 struct rnd_state *rnd,145 const char *who,146 unsigned long timeout)147{148 int err;149 150 err = expect_pfn_sg(pt, npages_fn, rnd, who, timeout);151 if (err)152 return err;153 154 err = expect_pfn_sg_page_iter(pt, who, timeout);155 if (err)156 return err;157 158 err = expect_pfn_sgtiter(pt, who, timeout);159 if (err)160 return err;161 162 return 0;163}164 165static unsigned int one(unsigned long n,166 unsigned long count,167 struct rnd_state *rnd)168{169 return 1;170}171 172static unsigned int grow(unsigned long n,173 unsigned long count,174 struct rnd_state *rnd)175{176 return n + 1;177}178 179static unsigned int shrink(unsigned long n,180 unsigned long count,181 struct rnd_state *rnd)182{183 return count - n;184}185 186static unsigned int random(unsigned long n,187 unsigned long count,188 struct rnd_state *rnd)189{190 return 1 + (prandom_u32_state(rnd) % 1024);191}192 193static unsigned int random_page_size_pages(unsigned long n,194 unsigned long count,195 struct rnd_state *rnd)196{197 /* 4K, 64K, 2M */198 static unsigned int page_count[] = {199 BIT(12) >> PAGE_SHIFT,200 BIT(16) >> PAGE_SHIFT,201 BIT(21) >> PAGE_SHIFT,202 };203 204 return page_count[(prandom_u32_state(rnd) % 3)];205}206 207static inline bool page_contiguous(struct page *first,208 struct page *last,209 unsigned long npages)210{211 return first + npages == last;212}213 214static int alloc_table(struct pfn_table *pt,215 unsigned long count, unsigned long max,216 npages_fn_t npages_fn,217 struct rnd_state *rnd,218 int alloc_error)219{220 struct scatterlist *sg;221 unsigned long n, pfn;222 223 /* restricted by sg_alloc_table */224 if (overflows_type(max, unsigned int))225 return -E2BIG;226 227 if (sg_alloc_table(&pt->st, max,228 GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN))229 return alloc_error;230 231 /* count should be less than 20 to prevent overflowing sg->length */232 GEM_BUG_ON(overflows_type(count * PAGE_SIZE, sg->length));233 234 /* Construct a table where each scatterlist contains different number235 * of entries. The idea is to check that we can iterate the individual236 * pages from inside the coalesced lists.237 */238 pt->start = PFN_BIAS;239 pfn = pt->start;240 sg = pt->st.sgl;241 for (n = 0; n < count; n++) {242 unsigned long npages = npages_fn(n, count, rnd);243 244 /* Nobody expects the Sparse Memmap! */245 if (!page_contiguous(pfn_to_page(pfn),246 pfn_to_page(pfn + npages),247 npages)) {248 sg_free_table(&pt->st);249 return -ENOSPC;250 }251 252 if (n)253 sg = sg_next(sg);254 sg_set_page(sg, pfn_to_page(pfn), npages * PAGE_SIZE, 0);255 256 GEM_BUG_ON(page_to_pfn(sg_page(sg)) != pfn);257 GEM_BUG_ON(sg->length != npages * PAGE_SIZE);258 GEM_BUG_ON(sg->offset != 0);259 260 pfn += npages;261 }262 sg_mark_end(sg);263 pt->st.nents = n;264 pt->end = pfn;265 266 return 0;267}268 269static const npages_fn_t npages_funcs[] = {270 one,271 grow,272 shrink,273 random,274 random_page_size_pages,275 NULL,276};277 278static int igt_sg_alloc(void *ignored)279{280 IGT_TIMEOUT(end_time);281 const unsigned long max_order = 20; /* approximating a 4GiB object */282 struct rnd_state prng;283 unsigned long prime;284 int alloc_error = -ENOMEM;285 286 for_each_prime_number(prime, max_order) {287 unsigned long size = BIT(prime);288 int offset;289 290 for (offset = -1; offset <= 1; offset++) {291 unsigned long sz = size + offset;292 const npages_fn_t *npages;293 struct pfn_table pt;294 int err;295 296 for (npages = npages_funcs; *npages; npages++) {297 prandom_seed_state(&prng,298 i915_selftest.random_seed);299 err = alloc_table(&pt, sz, sz, *npages, &prng,300 alloc_error);301 if (err == -ENOSPC)302 break;303 if (err)304 return err;305 306 prandom_seed_state(&prng,307 i915_selftest.random_seed);308 err = expect_pfn_sgtable(&pt, *npages, &prng,309 "sg_alloc_table",310 end_time);311 sg_free_table(&pt.st);312 if (err)313 return err;314 }315 }316 317 /* Test at least one continuation before accepting oom */318 if (size > SG_MAX_SINGLE_ALLOC)319 alloc_error = -ENOSPC;320 }321 322 return 0;323}324 325static int igt_sg_trim(void *ignored)326{327 IGT_TIMEOUT(end_time);328 const unsigned long max = PAGE_SIZE; /* not prime! */329 struct pfn_table pt;330 unsigned long prime;331 int alloc_error = -ENOMEM;332 333 for_each_prime_number(prime, max) {334 const npages_fn_t *npages;335 int err;336 337 for (npages = npages_funcs; *npages; npages++) {338 struct rnd_state prng;339 340 prandom_seed_state(&prng, i915_selftest.random_seed);341 err = alloc_table(&pt, prime, max, *npages, &prng,342 alloc_error);343 if (err == -ENOSPC)344 break;345 if (err)346 return err;347 348 if (i915_sg_trim(&pt.st)) {349 if (pt.st.orig_nents != prime ||350 pt.st.nents != prime) {351 pr_err("i915_sg_trim failed (nents %u, orig_nents %u), expected %lu\n",352 pt.st.nents, pt.st.orig_nents, prime);353 err = -EINVAL;354 } else {355 prandom_seed_state(&prng,356 i915_selftest.random_seed);357 err = expect_pfn_sgtable(&pt,358 *npages, &prng,359 "i915_sg_trim",360 end_time);361 }362 }363 sg_free_table(&pt.st);364 if (err)365 return err;366 }367 368 /* Test at least one continuation before accepting oom */369 if (prime > SG_MAX_SINGLE_ALLOC)370 alloc_error = -ENOSPC;371 }372 373 return 0;374}375 376int scatterlist_mock_selftests(void)377{378 static const struct i915_subtest tests[] = {379 SUBTEST(igt_sg_alloc),380 SUBTEST(igt_sg_trim),381 };382 383 return i915_subtests(tests, NULL);384}385