1 /*-
2 * Copyright (c) 2010 Isilon Systems, Inc.
3 * Copyright (c) 2016 Matthew Macy (mmacy@mattmacy.io)
4 * Copyright (c) 2017 Mellanox Technologies, Ltd.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice unmodified, this list of conditions, and the following
12 * disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/malloc.h>
32 #include <sys/kernel.h>
33 #include <sys/sysctl.h>
34 #include <sys/lock.h>
35 #include <sys/mutex.h>
36 #include <sys/rwlock.h>
37 #include <sys/proc.h>
38 #include <sys/sched.h>
39 #include <sys/memrange.h>
40
41 #include <machine/bus.h>
42
43 #include <vm/vm.h>
44 #include <vm/pmap.h>
45 #include <vm/vm_param.h>
46 #include <vm/vm_kern.h>
47 #include <vm/vm_object.h>
48 #include <vm/vm_map.h>
49 #include <vm/vm_page.h>
50 #include <vm/vm_pageout.h>
51 #include <vm/vm_pager.h>
52 #include <vm/vm_radix.h>
53 #include <vm/vm_reserv.h>
54 #include <vm/vm_extern.h>
55
56 #include <vm/uma.h>
57 #include <vm/uma_int.h>
58
59 #include <linux/gfp.h>
60 #include <linux/mm.h>
61 #include <linux/preempt.h>
62 #include <linux/fs.h>
63 #include <linux/shmem_fs.h>
64 #include <linux/kernel.h>
65 #include <linux/idr.h>
66 #include <linux/io.h>
67 #include <linux/io-mapping.h>
68
69 #ifdef __i386__
70 DEFINE_IDR(mtrr_idr);
71 static MALLOC_DEFINE(M_LKMTRR, "idr", "Linux MTRR compat");
72 extern int pat_works;
73 #endif
74
75 void
si_meminfo(struct sysinfo * si)76 si_meminfo(struct sysinfo *si)
77 {
78 si->totalram = physmem;
79 si->freeram = vm_free_count();
80 si->totalhigh = 0;
81 si->freehigh = 0;
82 si->mem_unit = PAGE_SIZE;
83 }
84
85 void *
linux_page_address(struct page * page)86 linux_page_address(struct page *page)
87 {
88
89 if (page->object != kernel_object) {
90 return (PMAP_HAS_DMAP ?
91 ((void *)(uintptr_t)PHYS_TO_DMAP(page_to_phys(page))) :
92 NULL);
93 }
94 return ((void *)(uintptr_t)(VM_MIN_KERNEL_ADDRESS +
95 IDX_TO_OFF(page->pindex)));
96 }
97
98 struct page *
linux_alloc_pages(gfp_t flags,unsigned int order)99 linux_alloc_pages(gfp_t flags, unsigned int order)
100 {
101 struct page *page;
102
103 if (PMAP_HAS_DMAP) {
104 unsigned long npages = 1UL << order;
105 int req = VM_ALLOC_WIRED;
106
107 if ((flags & M_ZERO) != 0)
108 req |= VM_ALLOC_ZERO;
109 if (order == 0 && (flags & GFP_DMA32) == 0) {
110 page = vm_page_alloc_noobj(req);
111 if (page == NULL)
112 return (NULL);
113 } else {
114 vm_paddr_t pmax = (flags & GFP_DMA32) ?
115 BUS_SPACE_MAXADDR_32BIT : BUS_SPACE_MAXADDR;
116 retry:
117 page = vm_page_alloc_noobj_contig(req, npages, 0, pmax,
118 PAGE_SIZE, 0, VM_MEMATTR_DEFAULT);
119 if (page == NULL) {
120 if (flags & M_WAITOK) {
121 int err = vm_page_reclaim_contig(req,
122 npages, 0, pmax, PAGE_SIZE, 0);
123 if (err == ENOMEM)
124 vm_wait(NULL);
125 else if (err != 0)
126 return (NULL);
127 flags &= ~M_WAITOK;
128 goto retry;
129 }
130 return (NULL);
131 }
132 }
133 } else {
134 vm_offset_t vaddr;
135
136 vaddr = linux_alloc_kmem(flags, order);
137 if (vaddr == 0)
138 return (NULL);
139
140 page = virt_to_page((void *)vaddr);
141
142 KASSERT(vaddr == (vm_offset_t)page_address(page),
143 ("Page address mismatch"));
144 }
145
146 return (page);
147 }
148
149 static void
_linux_free_kmem(vm_offset_t addr,unsigned int order)150 _linux_free_kmem(vm_offset_t addr, unsigned int order)
151 {
152 size_t size = ((size_t)PAGE_SIZE) << order;
153
154 kmem_free((void *)addr, size);
155 }
156
157 void
linux_free_pages(struct page * page,unsigned int order)158 linux_free_pages(struct page *page, unsigned int order)
159 {
160 if (PMAP_HAS_DMAP) {
161 unsigned long npages = 1UL << order;
162 unsigned long x;
163
164 for (x = 0; x != npages; x++) {
165 vm_page_t pgo = page + x;
166
167 if (vm_page_unwire_noq(pgo))
168 vm_page_free(pgo);
169 }
170 } else {
171 vm_offset_t vaddr;
172
173 vaddr = (vm_offset_t)page_address(page);
174
175 _linux_free_kmem(vaddr, order);
176 }
177 }
178
179 vm_offset_t
linux_alloc_kmem(gfp_t flags,unsigned int order)180 linux_alloc_kmem(gfp_t flags, unsigned int order)
181 {
182 size_t size = ((size_t)PAGE_SIZE) << order;
183 void *addr;
184
185 if ((flags & GFP_DMA32) == 0) {
186 addr = kmem_malloc(size, flags & GFP_NATIVE_MASK);
187 } else {
188 addr = kmem_alloc_contig(size, flags & GFP_NATIVE_MASK, 0,
189 BUS_SPACE_MAXADDR_32BIT, PAGE_SIZE, 0, VM_MEMATTR_DEFAULT);
190 }
191 return ((vm_offset_t)addr);
192 }
193
194 void
linux_free_kmem(vm_offset_t addr,unsigned int order)195 linux_free_kmem(vm_offset_t addr, unsigned int order)
196 {
197 KASSERT((addr & ~PAGE_MASK) == 0,
198 ("%s: addr %p is not page aligned", __func__, (void *)addr));
199
200 if (addr >= VM_MIN_KERNEL_ADDRESS && addr < VM_MAX_KERNEL_ADDRESS) {
201 _linux_free_kmem(addr, order);
202 } else {
203 vm_page_t page;
204
205 page = PHYS_TO_VM_PAGE(DMAP_TO_PHYS(addr));
206 linux_free_pages(page, order);
207 }
208 }
209
210 static int
linux_get_user_pages_internal(vm_map_t map,unsigned long start,int nr_pages,int write,struct page ** pages)211 linux_get_user_pages_internal(vm_map_t map, unsigned long start, int nr_pages,
212 int write, struct page **pages)
213 {
214 vm_prot_t prot;
215 size_t len;
216 int count;
217
218 prot = write ? (VM_PROT_READ | VM_PROT_WRITE) : VM_PROT_READ;
219 len = ptoa((vm_offset_t)nr_pages);
220 count = vm_fault_quick_hold_pages(map, start, len, prot, pages, nr_pages);
221 return (count == -1 ? -EFAULT : nr_pages);
222 }
223
224 int
__get_user_pages_fast(unsigned long start,int nr_pages,int write,struct page ** pages)225 __get_user_pages_fast(unsigned long start, int nr_pages, int write,
226 struct page **pages)
227 {
228 vm_map_t map;
229 vm_page_t *mp;
230 vm_offset_t va;
231 vm_offset_t end;
232 vm_prot_t prot;
233 int count;
234
235 if (nr_pages == 0 || in_interrupt())
236 return (0);
237
238 MPASS(pages != NULL);
239 map = &curthread->td_proc->p_vmspace->vm_map;
240 end = start + ptoa((vm_offset_t)nr_pages);
241 if (!vm_map_range_valid(map, start, end))
242 return (-EINVAL);
243 prot = write ? (VM_PROT_READ | VM_PROT_WRITE) : VM_PROT_READ;
244 for (count = 0, mp = pages, va = start; va < end;
245 mp++, va += PAGE_SIZE, count++) {
246 *mp = pmap_extract_and_hold(map->pmap, va, prot);
247 if (*mp == NULL)
248 break;
249
250 if ((prot & VM_PROT_WRITE) != 0 &&
251 (*mp)->dirty != VM_PAGE_BITS_ALL) {
252 /*
253 * Explicitly dirty the physical page. Otherwise, the
254 * caller's changes may go unnoticed because they are
255 * performed through an unmanaged mapping or by a DMA
256 * operation.
257 *
258 * The object lock is not held here.
259 * See vm_page_clear_dirty_mask().
260 */
261 vm_page_dirty(*mp);
262 }
263 }
264 return (count);
265 }
266
267 long
get_user_pages_remote(struct task_struct * task,struct mm_struct * mm,unsigned long start,unsigned long nr_pages,unsigned int gup_flags,struct page ** pages,struct vm_area_struct ** vmas)268 get_user_pages_remote(struct task_struct *task, struct mm_struct *mm,
269 unsigned long start, unsigned long nr_pages, unsigned int gup_flags,
270 struct page **pages, struct vm_area_struct **vmas)
271 {
272 vm_map_t map;
273
274 map = &task->task_thread->td_proc->p_vmspace->vm_map;
275 return (linux_get_user_pages_internal(map, start, nr_pages,
276 !!(gup_flags & FOLL_WRITE), pages));
277 }
278
279 long
get_user_pages(unsigned long start,unsigned long nr_pages,unsigned int gup_flags,struct page ** pages,struct vm_area_struct ** vmas)280 get_user_pages(unsigned long start, unsigned long nr_pages,
281 unsigned int gup_flags, struct page **pages, struct vm_area_struct **vmas)
282 {
283 vm_map_t map;
284
285 map = &curthread->td_proc->p_vmspace->vm_map;
286 return (linux_get_user_pages_internal(map, start, nr_pages,
287 !!(gup_flags & FOLL_WRITE), pages));
288 }
289
290 int
is_vmalloc_addr(const void * addr)291 is_vmalloc_addr(const void *addr)
292 {
293 return (vtoslab((vm_offset_t)addr & ~UMA_SLAB_MASK) != NULL);
294 }
295
296 vm_fault_t
lkpi_vmf_insert_pfn_prot_locked(struct vm_area_struct * vma,unsigned long addr,unsigned long pfn,pgprot_t prot)297 lkpi_vmf_insert_pfn_prot_locked(struct vm_area_struct *vma, unsigned long addr,
298 unsigned long pfn, pgprot_t prot)
299 {
300 vm_object_t vm_obj = vma->vm_obj;
301 vm_object_t tmp_obj;
302 vm_page_t page;
303 vm_pindex_t pindex;
304
305 VM_OBJECT_ASSERT_WLOCKED(vm_obj);
306 pindex = OFF_TO_IDX(addr - vma->vm_start);
307 if (vma->vm_pfn_count == 0)
308 vma->vm_pfn_first = pindex;
309 MPASS(pindex <= OFF_TO_IDX(vma->vm_end));
310
311 retry:
312 page = vm_page_grab(vm_obj, pindex, VM_ALLOC_NOCREAT);
313 if (page == NULL) {
314 page = PHYS_TO_VM_PAGE(IDX_TO_OFF(pfn));
315 if (!vm_page_busy_acquire(page, VM_ALLOC_WAITFAIL))
316 goto retry;
317 if (page->object != NULL) {
318 tmp_obj = page->object;
319 vm_page_xunbusy(page);
320 VM_OBJECT_WUNLOCK(vm_obj);
321 VM_OBJECT_WLOCK(tmp_obj);
322 if (page->object == tmp_obj &&
323 vm_page_busy_acquire(page, VM_ALLOC_WAITFAIL)) {
324 KASSERT(page->object == tmp_obj,
325 ("page has changed identity"));
326 KASSERT((page->oflags & VPO_UNMANAGED) == 0,
327 ("page does not belong to shmem"));
328 vm_pager_page_unswapped(page);
329 if (pmap_page_is_mapped(page)) {
330 vm_page_xunbusy(page);
331 VM_OBJECT_WUNLOCK(tmp_obj);
332 printf("%s: page rename failed: page "
333 "is mapped\n", __func__);
334 VM_OBJECT_WLOCK(vm_obj);
335 return (VM_FAULT_NOPAGE);
336 }
337 vm_page_remove(page);
338 }
339 VM_OBJECT_WUNLOCK(tmp_obj);
340 VM_OBJECT_WLOCK(vm_obj);
341 goto retry;
342 }
343 if (vm_page_insert(page, vm_obj, pindex)) {
344 vm_page_xunbusy(page);
345 return (VM_FAULT_OOM);
346 }
347 vm_page_valid(page);
348 }
349 pmap_page_set_memattr(page, pgprot2cachemode(prot));
350 vma->vm_pfn_count++;
351
352 return (VM_FAULT_NOPAGE);
353 }
354
355 int
lkpi_remap_pfn_range(struct vm_area_struct * vma,unsigned long start_addr,unsigned long start_pfn,unsigned long size,pgprot_t prot)356 lkpi_remap_pfn_range(struct vm_area_struct *vma, unsigned long start_addr,
357 unsigned long start_pfn, unsigned long size, pgprot_t prot)
358 {
359 vm_object_t vm_obj;
360 unsigned long addr, pfn;
361 int err = 0;
362
363 vm_obj = vma->vm_obj;
364
365 VM_OBJECT_WLOCK(vm_obj);
366 for (addr = start_addr, pfn = start_pfn;
367 addr < start_addr + size;
368 addr += PAGE_SIZE) {
369 vm_fault_t ret;
370 retry:
371 ret = lkpi_vmf_insert_pfn_prot_locked(vma, addr, pfn, prot);
372
373 if ((ret & VM_FAULT_OOM) != 0) {
374 VM_OBJECT_WUNLOCK(vm_obj);
375 vm_wait(NULL);
376 VM_OBJECT_WLOCK(vm_obj);
377 goto retry;
378 }
379
380 if ((ret & VM_FAULT_ERROR) != 0) {
381 err = -EFAULT;
382 break;
383 }
384
385 pfn++;
386 }
387 VM_OBJECT_WUNLOCK(vm_obj);
388
389 if (unlikely(err)) {
390 zap_vma_ptes(vma, start_addr,
391 (pfn - start_pfn) << PAGE_SHIFT);
392 return (err);
393 }
394
395 return (0);
396 }
397
398 int
lkpi_io_mapping_map_user(struct io_mapping * iomap,struct vm_area_struct * vma,unsigned long addr,unsigned long pfn,unsigned long size)399 lkpi_io_mapping_map_user(struct io_mapping *iomap,
400 struct vm_area_struct *vma, unsigned long addr,
401 unsigned long pfn, unsigned long size)
402 {
403 pgprot_t prot;
404 int ret;
405
406 prot = cachemode2protval(iomap->attr);
407 ret = lkpi_remap_pfn_range(vma, addr, pfn, size, prot);
408
409 return (ret);
410 }
411
412 /*
413 * Although FreeBSD version of unmap_mapping_range has semantics and types of
414 * parameters compatible with Linux version, the values passed in are different
415 * @obj should match to vm_private_data field of vm_area_struct returned by
416 * mmap file operation handler, see linux_file_mmap_single() sources
417 * @holelen should match to size of area to be munmapped.
418 */
419 void
lkpi_unmap_mapping_range(void * obj,loff_t const holebegin __unused,loff_t const holelen,int even_cows __unused)420 lkpi_unmap_mapping_range(void *obj, loff_t const holebegin __unused,
421 loff_t const holelen, int even_cows __unused)
422 {
423 vm_object_t devobj;
424 vm_page_t page;
425 int i, page_count;
426
427 devobj = cdev_pager_lookup(obj);
428 if (devobj != NULL) {
429 page_count = OFF_TO_IDX(holelen);
430
431 VM_OBJECT_WLOCK(devobj);
432 retry:
433 for (i = 0; i < page_count; i++) {
434 page = vm_page_lookup(devobj, i);
435 if (page == NULL)
436 continue;
437 if (!vm_page_busy_acquire(page, VM_ALLOC_WAITFAIL))
438 goto retry;
439 cdev_pager_free_page(devobj, page);
440 }
441 VM_OBJECT_WUNLOCK(devobj);
442 vm_object_deallocate(devobj);
443 }
444 }
445
446 int
lkpi_arch_phys_wc_add(unsigned long base,unsigned long size)447 lkpi_arch_phys_wc_add(unsigned long base, unsigned long size)
448 {
449 #ifdef __i386__
450 struct mem_range_desc *mrdesc;
451 int error, id, act;
452
453 /* If PAT is available, do nothing */
454 if (pat_works)
455 return (0);
456
457 mrdesc = malloc(sizeof(*mrdesc), M_LKMTRR, M_WAITOK);
458 mrdesc->mr_base = base;
459 mrdesc->mr_len = size;
460 mrdesc->mr_flags = MDF_WRITECOMBINE;
461 strlcpy(mrdesc->mr_owner, "drm", sizeof(mrdesc->mr_owner));
462 act = MEMRANGE_SET_UPDATE;
463 error = mem_range_attr_set(mrdesc, &act);
464 if (error == 0) {
465 error = idr_get_new(&mtrr_idr, mrdesc, &id);
466 MPASS(idr_find(&mtrr_idr, id) == mrdesc);
467 if (error != 0) {
468 act = MEMRANGE_SET_REMOVE;
469 mem_range_attr_set(mrdesc, &act);
470 }
471 }
472 if (error != 0) {
473 free(mrdesc, M_LKMTRR);
474 pr_warn(
475 "Failed to add WC MTRR for [%p-%p]: %d; "
476 "performance may suffer\n",
477 (void *)base, (void *)(base + size - 1), error);
478 } else
479 pr_warn("Successfully added WC MTRR for [%p-%p]\n",
480 (void *)base, (void *)(base + size - 1));
481
482 return (error != 0 ? -error : id + __MTRR_ID_BASE);
483 #else
484 return (0);
485 #endif
486 }
487
488 void
lkpi_arch_phys_wc_del(int reg)489 lkpi_arch_phys_wc_del(int reg)
490 {
491 #ifdef __i386__
492 struct mem_range_desc *mrdesc;
493 int act;
494
495 /* Check if arch_phys_wc_add() failed. */
496 if (reg < __MTRR_ID_BASE)
497 return;
498
499 mrdesc = idr_find(&mtrr_idr, reg - __MTRR_ID_BASE);
500 MPASS(mrdesc != NULL);
501 idr_remove(&mtrr_idr, reg - __MTRR_ID_BASE);
502 act = MEMRANGE_SET_REMOVE;
503 mem_range_attr_set(mrdesc, &act);
504 free(mrdesc, M_LKMTRR);
505 #endif
506 }
507
508 /*
509 * This is a highly simplified version of the Linux page_frag_cache.
510 * We only support up-to 1 single page as fragment size and we will
511 * always return a full page. This may be wasteful on small objects
512 * but the only known consumer (mt76) is either asking for a half-page
513 * or a full page. If this was to become a problem we can implement
514 * a more elaborate version.
515 */
516 void *
linuxkpi_page_frag_alloc(struct page_frag_cache * pfc,size_t fragsz,gfp_t gfp)517 linuxkpi_page_frag_alloc(struct page_frag_cache *pfc,
518 size_t fragsz, gfp_t gfp)
519 {
520 vm_page_t pages;
521
522 if (fragsz == 0)
523 return (NULL);
524
525 KASSERT(fragsz <= PAGE_SIZE, ("%s: fragsz %zu > PAGE_SIZE not yet "
526 "supported", __func__, fragsz));
527
528 pages = alloc_pages(gfp, flsl(howmany(fragsz, PAGE_SIZE) - 1));
529 if (pages == NULL)
530 return (NULL);
531 pfc->va = linux_page_address(pages);
532
533 /* Passed in as "count" to __page_frag_cache_drain(). Unused by us. */
534 pfc->pagecnt_bias = 0;
535
536 return (pfc->va);
537 }
538
539 void
linuxkpi_page_frag_free(void * addr)540 linuxkpi_page_frag_free(void *addr)
541 {
542 vm_page_t page;
543
544 page = virt_to_page(addr);
545 linux_free_pages(page, 0);
546 }
547
548 void
linuxkpi__page_frag_cache_drain(struct page * page,size_t count __unused)549 linuxkpi__page_frag_cache_drain(struct page *page, size_t count __unused)
550 {
551
552 linux_free_pages(page, 0);
553 }
554