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: stable/11/sys/compat/linuxkpi/common/src/linux_page.c 345927 2019-04-05 11:24:05Z hselasky $"); 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 72void 73si_meminfo(struct sysinfo *si) 74{ 75 si->totalram = physmem; 76 si->totalhigh = 0; 77 si->mem_unit = PAGE_SIZE; 78} 79 80void * 81linux_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 95vm_page_t 96linux_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; 111retry: 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 153void 154linux_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 176vm_offset_t 177linux_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 192void 193linux_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 200static int 201linux_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 226int 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 275long 276get_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 287long 288get_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 298int 299is_vmalloc_addr(const void *addr) 300{ 301 return (vtoslab((vm_offset_t)addr & ~UMA_SLAB_MASK) != NULL); 302} 303 304struct page * 305linux_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 340struct linux_file * 341linux_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); 369err_1: 370 kfree(filp); 371err_0: 372 return (ERR_PTR(error)); 373} 374 375static vm_ooffset_t 376linux_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 389unsigned long 390linux_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 396void 397linux_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