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 addr = kmem_alloc_contig(size, flags & GFP_NATIVE_MASK, 0,
186 ((flags & GFP_DMA32) == 0) ? -1UL : BUS_SPACE_MAXADDR_32BIT,
187 PAGE_SIZE, 0, VM_MEMATTR_DEFAULT);
188
189 return ((vm_offset_t)addr);
190 }
191
192 void
linux_free_kmem(vm_offset_t addr,unsigned int order)193 linux_free_kmem(vm_offset_t addr, unsigned int order)
194 {
195 KASSERT((addr & ~PAGE_MASK) == 0,
196 ("%s: addr %p is not page aligned", __func__, (void *)addr));
197
198 if (addr >= VM_MIN_KERNEL_ADDRESS && addr < VM_MAX_KERNEL_ADDRESS) {
199 _linux_free_kmem(addr, order);
200 } else {
201 vm_page_t page;
202
203 page = PHYS_TO_VM_PAGE(DMAP_TO_PHYS(addr));
204 linux_free_pages(page, order);
205 }
206 }
207
208 static int
linux_get_user_pages_internal(vm_map_t map,unsigned long start,int nr_pages,int write,struct page ** pages)209 linux_get_user_pages_internal(vm_map_t map, unsigned long start, int nr_pages,
210 int write, struct page **pages)
211 {
212 vm_prot_t prot;
213 size_t len;
214 int count;
215
216 prot = write ? (VM_PROT_READ | VM_PROT_WRITE) : VM_PROT_READ;
217 len = ptoa((vm_offset_t)nr_pages);
218 count = vm_fault_quick_hold_pages(map, start, len, prot, pages, nr_pages);
219 return (count == -1 ? -EFAULT : nr_pages);
220 }
221
222 int
__get_user_pages_fast(unsigned long start,int nr_pages,int write,struct page ** pages)223 __get_user_pages_fast(unsigned long start, int nr_pages, int write,
224 struct page **pages)
225 {
226 vm_map_t map;
227 vm_page_t *mp;
228 vm_offset_t va;
229 vm_offset_t end;
230 vm_prot_t prot;
231 int count;
232
233 if (nr_pages == 0 || in_interrupt())
234 return (0);
235
236 MPASS(pages != NULL);
237 map = &curthread->td_proc->p_vmspace->vm_map;
238 end = start + ptoa((vm_offset_t)nr_pages);
239 if (!vm_map_range_valid(map, start, end))
240 return (-EINVAL);
241 prot = write ? (VM_PROT_READ | VM_PROT_WRITE) : VM_PROT_READ;
242 for (count = 0, mp = pages, va = start; va < end;
243 mp++, va += PAGE_SIZE, count++) {
244 *mp = pmap_extract_and_hold(map->pmap, va, prot);
245 if (*mp == NULL)
246 break;
247
248 if ((prot & VM_PROT_WRITE) != 0 &&
249 (*mp)->dirty != VM_PAGE_BITS_ALL) {
250 /*
251 * Explicitly dirty the physical page. Otherwise, the
252 * caller's changes may go unnoticed because they are
253 * performed through an unmanaged mapping or by a DMA
254 * operation.
255 *
256 * The object lock is not held here.
257 * See vm_page_clear_dirty_mask().
258 */
259 vm_page_dirty(*mp);
260 }
261 }
262 return (count);
263 }
264
265 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)266 get_user_pages_remote(struct task_struct *task, struct mm_struct *mm,
267 unsigned long start, unsigned long nr_pages, unsigned int gup_flags,
268 struct page **pages, struct vm_area_struct **vmas)
269 {
270 vm_map_t map;
271
272 map = &task->task_thread->td_proc->p_vmspace->vm_map;
273 return (linux_get_user_pages_internal(map, start, nr_pages,
274 !!(gup_flags & FOLL_WRITE), pages));
275 }
276
277 long
lkpi_get_user_pages(unsigned long start,unsigned long nr_pages,unsigned int gup_flags,struct page ** pages)278 lkpi_get_user_pages(unsigned long start, unsigned long nr_pages,
279 unsigned int gup_flags, struct page **pages)
280 {
281 vm_map_t map;
282
283 map = &curthread->td_proc->p_vmspace->vm_map;
284 return (linux_get_user_pages_internal(map, start, nr_pages,
285 !!(gup_flags & FOLL_WRITE), pages));
286 }
287
288 int
is_vmalloc_addr(const void * addr)289 is_vmalloc_addr(const void *addr)
290 {
291 return (vtoslab((vm_offset_t)addr & ~UMA_SLAB_MASK) != NULL);
292 }
293
294 vm_fault_t
lkpi_vmf_insert_pfn_prot_locked(struct vm_area_struct * vma,unsigned long addr,unsigned long pfn,pgprot_t prot)295 lkpi_vmf_insert_pfn_prot_locked(struct vm_area_struct *vma, unsigned long addr,
296 unsigned long pfn, pgprot_t prot)
297 {
298 vm_object_t vm_obj = vma->vm_obj;
299 vm_object_t tmp_obj;
300 vm_page_t page;
301 vm_pindex_t pindex;
302
303 VM_OBJECT_ASSERT_WLOCKED(vm_obj);
304 pindex = OFF_TO_IDX(addr - vma->vm_start);
305 if (vma->vm_pfn_count == 0)
306 vma->vm_pfn_first = pindex;
307 MPASS(pindex <= OFF_TO_IDX(vma->vm_end));
308
309 retry:
310 page = vm_page_grab(vm_obj, pindex, VM_ALLOC_NOCREAT);
311 if (page == NULL) {
312 page = PHYS_TO_VM_PAGE(IDX_TO_OFF(pfn));
313 if (!vm_page_busy_acquire(page, VM_ALLOC_WAITFAIL))
314 goto retry;
315 if (page->object != NULL) {
316 tmp_obj = page->object;
317 vm_page_xunbusy(page);
318 VM_OBJECT_WUNLOCK(vm_obj);
319 VM_OBJECT_WLOCK(tmp_obj);
320 if (page->object == tmp_obj &&
321 vm_page_busy_acquire(page, VM_ALLOC_WAITFAIL)) {
322 KASSERT(page->object == tmp_obj,
323 ("page has changed identity"));
324 KASSERT((page->oflags & VPO_UNMANAGED) == 0,
325 ("page does not belong to shmem"));
326 vm_pager_page_unswapped(page);
327 if (pmap_page_is_mapped(page)) {
328 vm_page_xunbusy(page);
329 VM_OBJECT_WUNLOCK(tmp_obj);
330 printf("%s: page rename failed: page "
331 "is mapped\n", __func__);
332 VM_OBJECT_WLOCK(vm_obj);
333 return (VM_FAULT_NOPAGE);
334 }
335 vm_page_remove(page);
336 }
337 VM_OBJECT_WUNLOCK(tmp_obj);
338 VM_OBJECT_WLOCK(vm_obj);
339 goto retry;
340 }
341 if (vm_page_insert(page, vm_obj, pindex)) {
342 vm_page_xunbusy(page);
343 return (VM_FAULT_OOM);
344 }
345 vm_page_valid(page);
346 }
347 pmap_page_set_memattr(page, pgprot2cachemode(prot));
348 vma->vm_pfn_count++;
349
350 return (VM_FAULT_NOPAGE);
351 }
352
353 int
lkpi_remap_pfn_range(struct vm_area_struct * vma,unsigned long start_addr,unsigned long start_pfn,unsigned long size,pgprot_t prot)354 lkpi_remap_pfn_range(struct vm_area_struct *vma, unsigned long start_addr,
355 unsigned long start_pfn, unsigned long size, pgprot_t prot)
356 {
357 vm_object_t vm_obj;
358 unsigned long addr, pfn;
359 int err = 0;
360
361 vm_obj = vma->vm_obj;
362
363 VM_OBJECT_WLOCK(vm_obj);
364 for (addr = start_addr, pfn = start_pfn;
365 addr < start_addr + size;
366 addr += PAGE_SIZE) {
367 vm_fault_t ret;
368 retry:
369 ret = lkpi_vmf_insert_pfn_prot_locked(vma, addr, pfn, prot);
370
371 if ((ret & VM_FAULT_OOM) != 0) {
372 VM_OBJECT_WUNLOCK(vm_obj);
373 vm_wait(NULL);
374 VM_OBJECT_WLOCK(vm_obj);
375 goto retry;
376 }
377
378 if ((ret & VM_FAULT_ERROR) != 0) {
379 err = -EFAULT;
380 break;
381 }
382
383 pfn++;
384 }
385 VM_OBJECT_WUNLOCK(vm_obj);
386
387 if (unlikely(err)) {
388 zap_vma_ptes(vma, start_addr,
389 (pfn - start_pfn) << PAGE_SHIFT);
390 return (err);
391 }
392
393 return (0);
394 }
395
396 int
lkpi_io_mapping_map_user(struct io_mapping * iomap,struct vm_area_struct * vma,unsigned long addr,unsigned long pfn,unsigned long size)397 lkpi_io_mapping_map_user(struct io_mapping *iomap,
398 struct vm_area_struct *vma, unsigned long addr,
399 unsigned long pfn, unsigned long size)
400 {
401 pgprot_t prot;
402 int ret;
403
404 prot = cachemode2protval(iomap->attr);
405 ret = lkpi_remap_pfn_range(vma, addr, pfn, size, prot);
406
407 return (ret);
408 }
409
410 /*
411 * Although FreeBSD version of unmap_mapping_range has semantics and types of
412 * parameters compatible with Linux version, the values passed in are different
413 * @obj should match to vm_private_data field of vm_area_struct returned by
414 * mmap file operation handler, see linux_file_mmap_single() sources
415 * @holelen should match to size of area to be munmapped.
416 */
417 void
lkpi_unmap_mapping_range(void * obj,loff_t const holebegin __unused,loff_t const holelen __unused,int even_cows __unused)418 lkpi_unmap_mapping_range(void *obj, loff_t const holebegin __unused,
419 loff_t const holelen __unused, int even_cows __unused)
420 {
421 vm_object_t devobj;
422
423 devobj = cdev_pager_lookup(obj);
424 if (devobj != NULL) {
425 cdev_mgtdev_pager_free_pages(devobj);
426 vm_object_deallocate(devobj);
427 }
428 }
429
430 int
lkpi_arch_phys_wc_add(unsigned long base,unsigned long size)431 lkpi_arch_phys_wc_add(unsigned long base, unsigned long size)
432 {
433 #ifdef __i386__
434 struct mem_range_desc *mrdesc;
435 int error, id, act;
436
437 /* If PAT is available, do nothing */
438 if (pat_works)
439 return (0);
440
441 mrdesc = malloc(sizeof(*mrdesc), M_LKMTRR, M_WAITOK);
442 mrdesc->mr_base = base;
443 mrdesc->mr_len = size;
444 mrdesc->mr_flags = MDF_WRITECOMBINE;
445 strlcpy(mrdesc->mr_owner, "drm", sizeof(mrdesc->mr_owner));
446 act = MEMRANGE_SET_UPDATE;
447 error = mem_range_attr_set(mrdesc, &act);
448 if (error == 0) {
449 error = idr_get_new(&mtrr_idr, mrdesc, &id);
450 MPASS(idr_find(&mtrr_idr, id) == mrdesc);
451 if (error != 0) {
452 act = MEMRANGE_SET_REMOVE;
453 mem_range_attr_set(mrdesc, &act);
454 }
455 }
456 if (error != 0) {
457 free(mrdesc, M_LKMTRR);
458 pr_warn(
459 "Failed to add WC MTRR for [%p-%p]: %d; "
460 "performance may suffer\n",
461 (void *)base, (void *)(base + size - 1), error);
462 } else
463 pr_warn("Successfully added WC MTRR for [%p-%p]\n",
464 (void *)base, (void *)(base + size - 1));
465
466 return (error != 0 ? -error : id + __MTRR_ID_BASE);
467 #else
468 return (0);
469 #endif
470 }
471
472 void
lkpi_arch_phys_wc_del(int reg)473 lkpi_arch_phys_wc_del(int reg)
474 {
475 #ifdef __i386__
476 struct mem_range_desc *mrdesc;
477 int act;
478
479 /* Check if arch_phys_wc_add() failed. */
480 if (reg < __MTRR_ID_BASE)
481 return;
482
483 mrdesc = idr_find(&mtrr_idr, reg - __MTRR_ID_BASE);
484 MPASS(mrdesc != NULL);
485 idr_remove(&mtrr_idr, reg - __MTRR_ID_BASE);
486 act = MEMRANGE_SET_REMOVE;
487 mem_range_attr_set(mrdesc, &act);
488 free(mrdesc, M_LKMTRR);
489 #endif
490 }
491
492 /*
493 * This is a highly simplified version of the Linux page_frag_cache.
494 * We only support up-to 1 single page as fragment size and we will
495 * always return a full page. This may be wasteful on small objects
496 * but the only known consumer (mt76) is either asking for a half-page
497 * or a full page. If this was to become a problem we can implement
498 * a more elaborate version.
499 */
500 void *
linuxkpi_page_frag_alloc(struct page_frag_cache * pfc,size_t fragsz,gfp_t gfp)501 linuxkpi_page_frag_alloc(struct page_frag_cache *pfc,
502 size_t fragsz, gfp_t gfp)
503 {
504 vm_page_t pages;
505
506 if (fragsz == 0)
507 return (NULL);
508
509 KASSERT(fragsz <= PAGE_SIZE, ("%s: fragsz %zu > PAGE_SIZE not yet "
510 "supported", __func__, fragsz));
511
512 pages = alloc_pages(gfp, flsl(howmany(fragsz, PAGE_SIZE) - 1));
513 if (pages == NULL)
514 return (NULL);
515 pfc->va = linux_page_address(pages);
516
517 /* Passed in as "count" to __page_frag_cache_drain(). Unused by us. */
518 pfc->pagecnt_bias = 0;
519
520 return (pfc->va);
521 }
522
523 void
linuxkpi_page_frag_free(void * addr)524 linuxkpi_page_frag_free(void *addr)
525 {
526 vm_page_t page;
527
528 page = virt_to_page(addr);
529 linux_free_pages(page, 0);
530 }
531
532 void
linuxkpi__page_frag_cache_drain(struct page * page,size_t count __unused)533 linuxkpi__page_frag_cache_drain(struct page *page, size_t count __unused)
534 {
535
536 linux_free_pages(page, 0);
537 }
538