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/cdefs.h>
30 __FBSDID("$FreeBSD$");
31
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/malloc.h>
35 #include <sys/kernel.h>
36 #include <sys/sysctl.h>
37 #include <sys/lock.h>
38 #include <sys/mutex.h>
39 #include <sys/rwlock.h>
40 #include <sys/proc.h>
41 #include <sys/sched.h>
42
43 #include <machine/bus.h>
44
45 #include <vm/vm.h>
46 #include <vm/pmap.h>
47 #include <vm/vm_param.h>
48 #include <vm/vm_kern.h>
49 #include <vm/vm_object.h>
50 #include <vm/vm_map.h>
51 #include <vm/vm_page.h>
52 #include <vm/vm_pageout.h>
53 #include <vm/vm_pager.h>
54 #include <vm/vm_radix.h>
55 #include <vm/vm_reserv.h>
56 #include <vm/vm_extern.h>
57
58 #include <vm/uma.h>
59 #include <vm/uma_int.h>
60
61 #include <linux/gfp.h>
62 #include <linux/mm.h>
63 #include <linux/preempt.h>
64 #include <linux/fs.h>
65
66 #if defined(__amd64__) || defined(__aarch64__) || defined(__riscv)
67 #define LINUXKPI_HAVE_DMAP
68 #else
69 #undef LINUXKPI_HAVE_DMAP
70 #endif
71
72 void
si_meminfo(struct sysinfo * si)73 si_meminfo(struct sysinfo *si)
74 {
75 si->totalram = physmem;
76 si->totalhigh = 0;
77 si->mem_unit = PAGE_SIZE;
78 }
79
80 void *
linux_page_address(struct page * page)81 linux_page_address(struct page *page)
82 {
83
84 if (page->object != kmem_object && page->object != kernel_object) {
85 #ifdef LINUXKPI_HAVE_DMAP
86 return ((void *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(page)));
87 #else
88 return (NULL);
89 #endif
90 }
91 return ((void *)(uintptr_t)(VM_MIN_KERNEL_ADDRESS +
92 IDX_TO_OFF(page->pindex)));
93 }
94
95 vm_page_t
linux_alloc_pages(gfp_t flags,unsigned int order)96 linux_alloc_pages(gfp_t flags, unsigned int order)
97 {
98 #ifdef LINUXKPI_HAVE_DMAP
99 unsigned long npages = 1UL << order;
100 int req = (flags & M_ZERO) ? (VM_ALLOC_ZERO | VM_ALLOC_NOOBJ |
101 VM_ALLOC_NORMAL) : (VM_ALLOC_NOOBJ | VM_ALLOC_NORMAL);
102 vm_page_t page;
103
104 if (order == 0 && (flags & GFP_DMA32) == 0) {
105 page = vm_page_alloc(NULL, 0, req);
106 if (page == NULL)
107 return (NULL);
108 } else {
109 vm_paddr_t pmax = (flags & GFP_DMA32) ?
110 BUS_SPACE_MAXADDR_32BIT : BUS_SPACE_MAXADDR;
111 retry:
112 page = vm_page_alloc_contig(NULL, 0, req,
113 npages, 0, pmax, PAGE_SIZE, 0, VM_MEMATTR_DEFAULT);
114
115 if (page == NULL) {
116 if (flags & M_WAITOK) {
117 if (!vm_page_reclaim_contig(req,
118 npages, 0, pmax, PAGE_SIZE, 0)) {
119 VM_WAIT;
120 }
121 flags &= ~M_WAITOK;
122 goto retry;
123 }
124 return (NULL);
125 }
126 }
127 if (flags & M_ZERO) {
128 unsigned long x;
129
130 for (x = 0; x != npages; x++) {
131 vm_page_t pgo = page + x;
132
133 if ((pgo->flags & PG_ZERO) == 0)
134 pmap_zero_page(pgo);
135 }
136 }
137 #else
138 vm_offset_t vaddr;
139 vm_page_t page;
140
141 vaddr = linux_alloc_kmem(flags, order);
142 if (vaddr == 0)
143 return (NULL);
144
145 page = PHYS_TO_VM_PAGE(vtophys((void *)vaddr));
146
147 KASSERT(vaddr == (vm_offset_t)page_address(page),
148 ("Page address mismatch"));
149 #endif
150 return (page);
151 }
152
153 void
linux_free_pages(vm_page_t page,unsigned int order)154 linux_free_pages(vm_page_t page, unsigned int order)
155 {
156 #ifdef LINUXKPI_HAVE_DMAP
157 unsigned long npages = 1UL << order;
158 unsigned long x;
159
160 for (x = 0; x != npages; x++) {
161 vm_page_t pgo = page + x;
162
163 vm_page_lock(pgo);
164 vm_page_free(pgo);
165 vm_page_unlock(pgo);
166 }
167 #else
168 vm_offset_t vaddr;
169
170 vaddr = (vm_offset_t)page_address(page);
171
172 linux_free_kmem(vaddr, order);
173 #endif
174 }
175
176 vm_offset_t
linux_alloc_kmem(gfp_t flags,unsigned int order)177 linux_alloc_kmem(gfp_t flags, unsigned int order)
178 {
179 size_t size = ((size_t)PAGE_SIZE) << order;
180 vm_offset_t addr;
181
182 if ((flags & GFP_DMA32) == 0) {
183 addr = kmem_malloc(kmem_arena, size, flags & GFP_NATIVE_MASK);
184 } else {
185 addr = kmem_alloc_contig(kmem_arena, size,
186 flags & GFP_NATIVE_MASK, 0, BUS_SPACE_MAXADDR_32BIT,
187 PAGE_SIZE, 0, VM_MEMATTR_DEFAULT);
188 }
189 return (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 size_t size = ((size_t)PAGE_SIZE) << order;
196
197 kmem_free(kmem_arena, addr, size);
198 }
199
200 static int
linux_get_user_pages_internal(vm_map_t map,unsigned long start,int nr_pages,int write,struct page ** pages)201 linux_get_user_pages_internal(vm_map_t map, unsigned long start, int nr_pages,
202 int write, struct page **pages)
203 {
204 vm_prot_t prot;
205 size_t len;
206 int count;
207 int i;
208
209 prot = write ? (VM_PROT_READ | VM_PROT_WRITE) : VM_PROT_READ;
210 len = ((size_t)nr_pages) << PAGE_SHIFT;
211 count = vm_fault_quick_hold_pages(map, start, len, prot, pages, nr_pages);
212 if (count == -1)
213 return (-EFAULT);
214
215 for (i = 0; i != nr_pages; i++) {
216 struct page *pg = pages[i];
217
218 vm_page_lock(pg);
219 vm_page_wire(pg);
220 vm_page_unhold(pg);
221 vm_page_unlock(pg);
222 }
223 return (nr_pages);
224 }
225
226 int
__get_user_pages_fast(unsigned long start,int nr_pages,int write,struct page ** pages)227 __get_user_pages_fast(unsigned long start, int nr_pages, int write,
228 struct page **pages)
229 {
230 vm_map_t map;
231 vm_page_t *mp;
232 vm_offset_t va;
233 vm_offset_t end;
234 vm_prot_t prot;
235 int count;
236
237 if (nr_pages == 0 || in_interrupt())
238 return (0);
239
240 MPASS(pages != NULL);
241 va = start;
242 map = &curthread->td_proc->p_vmspace->vm_map;
243 end = start + (((size_t)nr_pages) << PAGE_SHIFT);
244 if (start < vm_map_min(map) || end > vm_map_max(map))
245 return (-EINVAL);
246 prot = write ? (VM_PROT_READ | VM_PROT_WRITE) : VM_PROT_READ;
247 for (count = 0, mp = pages, va = start; va < end;
248 mp++, va += PAGE_SIZE, count++) {
249 *mp = pmap_extract_and_hold(map->pmap, va, prot);
250 if (*mp == NULL)
251 break;
252
253 vm_page_lock(*mp);
254 vm_page_wire(*mp);
255 vm_page_unhold(*mp);
256 vm_page_unlock(*mp);
257
258 if ((prot & VM_PROT_WRITE) != 0 &&
259 (*mp)->dirty != VM_PAGE_BITS_ALL) {
260 /*
261 * Explicitly dirty the physical page. Otherwise, the
262 * caller's changes may go unnoticed because they are
263 * performed through an unmanaged mapping or by a DMA
264 * operation.
265 *
266 * The object lock is not held here.
267 * See vm_page_clear_dirty_mask().
268 */
269 vm_page_dirty(*mp);
270 }
271 }
272 return (count);
273 }
274
275 long
get_user_pages_remote(struct task_struct * task,struct mm_struct * mm,unsigned long start,unsigned long nr_pages,int gup_flags,struct page ** pages,struct vm_area_struct ** vmas)276 get_user_pages_remote(struct task_struct *task, struct mm_struct *mm,
277 unsigned long start, unsigned long nr_pages, int gup_flags,
278 struct page **pages, struct vm_area_struct **vmas)
279 {
280 vm_map_t map;
281
282 map = &task->task_thread->td_proc->p_vmspace->vm_map;
283 return (linux_get_user_pages_internal(map, start, nr_pages,
284 !!(gup_flags & FOLL_WRITE), pages));
285 }
286
287 long
get_user_pages(unsigned long start,unsigned long nr_pages,int gup_flags,struct page ** pages,struct vm_area_struct ** vmas)288 get_user_pages(unsigned long start, unsigned long nr_pages, int gup_flags,
289 struct page **pages, struct vm_area_struct **vmas)
290 {
291 vm_map_t map;
292
293 map = &curthread->td_proc->p_vmspace->vm_map;
294 return (linux_get_user_pages_internal(map, start, nr_pages,
295 !!(gup_flags & FOLL_WRITE), pages));
296 }
297
298 int
is_vmalloc_addr(const void * addr)299 is_vmalloc_addr(const void *addr)
300 {
301 return (vtoslab((vm_offset_t)addr & ~UMA_SLAB_MASK) != NULL);
302 }
303
304 struct page *
linux_shmem_read_mapping_page_gfp(vm_object_t obj,int pindex,gfp_t gfp)305 linux_shmem_read_mapping_page_gfp(vm_object_t obj, int pindex, gfp_t gfp)
306 {
307 vm_page_t page;
308 int rv;
309
310 if ((gfp & GFP_NOWAIT) != 0)
311 panic("GFP_NOWAIT is unimplemented");
312
313 VM_OBJECT_WLOCK(obj);
314 page = vm_page_grab(obj, pindex, VM_ALLOC_NORMAL | VM_ALLOC_NOBUSY |
315 VM_ALLOC_WIRED);
316 if (page->valid != VM_PAGE_BITS_ALL) {
317 vm_page_xbusy(page);
318 if (vm_pager_has_page(obj, pindex, NULL, NULL)) {
319 rv = vm_pager_get_pages(obj, &page, 1, NULL, NULL);
320 if (rv != VM_PAGER_OK) {
321 vm_page_lock(page);
322 vm_page_unwire(page, PQ_NONE);
323 vm_page_free(page);
324 vm_page_unlock(page);
325 VM_OBJECT_WUNLOCK(obj);
326 return (ERR_PTR(-EINVAL));
327 }
328 MPASS(page->valid == VM_PAGE_BITS_ALL);
329 } else {
330 pmap_zero_page(page);
331 page->valid = VM_PAGE_BITS_ALL;
332 page->dirty = 0;
333 }
334 vm_page_xunbusy(page);
335 }
336 VM_OBJECT_WUNLOCK(obj);
337 return (page);
338 }
339
340 struct linux_file *
linux_shmem_file_setup(const char * name,loff_t size,unsigned long flags)341 linux_shmem_file_setup(const char *name, loff_t size, unsigned long flags)
342 {
343 struct fileobj {
344 struct linux_file file __aligned(sizeof(void *));
345 struct vnode vnode __aligned(sizeof(void *));
346 };
347 struct fileobj *fileobj;
348 struct linux_file *filp;
349 struct vnode *vp;
350 int error;
351
352 fileobj = kzalloc(sizeof(*fileobj), GFP_KERNEL);
353 if (fileobj == NULL) {
354 error = -ENOMEM;
355 goto err_0;
356 }
357 filp = &fileobj->file;
358 vp = &fileobj->vnode;
359
360 filp->f_count = 1;
361 filp->f_vnode = vp;
362 filp->f_shmem = vm_pager_allocate(OBJT_DEFAULT, NULL, size,
363 VM_PROT_READ | VM_PROT_WRITE, 0, curthread->td_ucred);
364 if (filp->f_shmem == NULL) {
365 error = -ENOMEM;
366 goto err_1;
367 }
368 return (filp);
369 err_1:
370 kfree(filp);
371 err_0:
372 return (ERR_PTR(error));
373 }
374
375 static vm_ooffset_t
linux_invalidate_mapping_pages_sub(vm_object_t obj,vm_pindex_t start,vm_pindex_t end,int flags)376 linux_invalidate_mapping_pages_sub(vm_object_t obj, vm_pindex_t start,
377 vm_pindex_t end, int flags)
378 {
379 int start_count, end_count;
380
381 VM_OBJECT_WLOCK(obj);
382 start_count = obj->resident_page_count;
383 vm_object_page_remove(obj, start, end, flags);
384 end_count = obj->resident_page_count;
385 VM_OBJECT_WUNLOCK(obj);
386 return (start_count - end_count);
387 }
388
389 unsigned long
linux_invalidate_mapping_pages(vm_object_t obj,pgoff_t start,pgoff_t end)390 linux_invalidate_mapping_pages(vm_object_t obj, pgoff_t start, pgoff_t end)
391 {
392
393 return (linux_invalidate_mapping_pages_sub(obj, start, end, OBJPR_CLEANONLY));
394 }
395
396 void
linux_shmem_truncate_range(vm_object_t obj,loff_t lstart,loff_t lend)397 linux_shmem_truncate_range(vm_object_t obj, loff_t lstart, loff_t lend)
398 {
399 vm_pindex_t start = OFF_TO_IDX(lstart + PAGE_SIZE - 1);
400 vm_pindex_t end = OFF_TO_IDX(lend + 1);
401
402 (void) linux_invalidate_mapping_pages_sub(obj, start, end, 0);
403 }
404