1 /*- 2 * Copyright (c) 2010 Isilon Systems, Inc. 3 * Copyright (c) 2016 Matt Macy (mmacy@nextbsd.org) 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 * 73 linux_page_address(struct page *page) 74 { 75 76 if (page->object != kmem_object && page->object != kernel_object) { 77 #ifdef LINUXKPI_HAVE_DMAP 78 return ((void *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(page))); 79 #else 80 return (NULL); 81 #endif 82 } 83 return ((void *)(uintptr_t)(VM_MIN_KERNEL_ADDRESS + 84 IDX_TO_OFF(page->pindex))); 85 } 86 87 vm_page_t 88 linux_alloc_pages(gfp_t flags, unsigned int order) 89 { 90 #ifdef LINUXKPI_HAVE_DMAP 91 unsigned long npages = 1UL << order; 92 int req = (flags & M_ZERO) ? (VM_ALLOC_ZERO | VM_ALLOC_NOOBJ | 93 VM_ALLOC_NORMAL) : (VM_ALLOC_NOOBJ | VM_ALLOC_NORMAL); 94 vm_page_t page; 95 96 if (order == 0 && (flags & GFP_DMA32) == 0) { 97 page = vm_page_alloc(NULL, 0, req); 98 if (page == NULL) 99 return (NULL); 100 } else { 101 vm_paddr_t pmax = (flags & GFP_DMA32) ? 102 BUS_SPACE_MAXADDR_32BIT : BUS_SPACE_MAXADDR; 103 retry: 104 page = vm_page_alloc_contig(NULL, 0, req, 105 npages, 0, pmax, PAGE_SIZE, 0, VM_MEMATTR_DEFAULT); 106 107 if (page == NULL) { 108 if (flags & M_WAITOK) { 109 if (!vm_page_reclaim_contig(req, 110 npages, 0, pmax, PAGE_SIZE, 0)) { 111 VM_WAIT; 112 } 113 flags &= ~M_WAITOK; 114 goto retry; 115 } 116 return (NULL); 117 } 118 } 119 if (flags & M_ZERO) { 120 unsigned long x; 121 122 for (x = 0; x != npages; x++) { 123 vm_page_t pgo = page + x; 124 125 if ((pgo->flags & PG_ZERO) == 0) 126 pmap_zero_page(pgo); 127 } 128 } 129 #else 130 vm_offset_t vaddr; 131 vm_page_t page; 132 133 vaddr = linux_alloc_kmem(flags, order); 134 if (vaddr == 0) 135 return (NULL); 136 137 page = PHYS_TO_VM_PAGE(vtophys((void *)vaddr)); 138 139 KASSERT(vaddr == (vm_offset_t)page_address(page), 140 ("Page address mismatch")); 141 #endif 142 return (page); 143 } 144 145 void 146 linux_free_pages(vm_page_t page, unsigned int order) 147 { 148 #ifdef LINUXKPI_HAVE_DMAP 149 unsigned long npages = 1UL << order; 150 unsigned long x; 151 152 for (x = 0; x != npages; x++) { 153 vm_page_t pgo = page + x; 154 155 vm_page_lock(pgo); 156 vm_page_free(pgo); 157 vm_page_unlock(pgo); 158 } 159 #else 160 vm_offset_t vaddr; 161 162 vaddr = (vm_offset_t)page_address(page); 163 164 linux_free_kmem(vaddr, order); 165 #endif 166 } 167 168 vm_offset_t 169 linux_alloc_kmem(gfp_t flags, unsigned int order) 170 { 171 size_t size = ((size_t)PAGE_SIZE) << order; 172 vm_offset_t addr; 173 174 if ((flags & GFP_DMA32) == 0) { 175 addr = kmem_malloc(kmem_arena, size, flags & GFP_NATIVE_MASK); 176 } else { 177 addr = kmem_alloc_contig(kmem_arena, size, 178 flags & GFP_NATIVE_MASK, 0, BUS_SPACE_MAXADDR_32BIT, 179 PAGE_SIZE, 0, VM_MEMATTR_DEFAULT); 180 } 181 return (addr); 182 } 183 184 void 185 linux_free_kmem(vm_offset_t addr, unsigned int order) 186 { 187 size_t size = ((size_t)PAGE_SIZE) << order; 188 189 kmem_free(kmem_arena, addr, size); 190 } 191 192 static int 193 linux_get_user_pages_internal(vm_map_t map, unsigned long start, int nr_pages, 194 int write, struct page **pages) 195 { 196 vm_prot_t prot; 197 size_t len; 198 int count; 199 int i; 200 201 prot = write ? (VM_PROT_READ | VM_PROT_WRITE) : VM_PROT_READ; 202 len = ((size_t)nr_pages) << PAGE_SHIFT; 203 count = vm_fault_quick_hold_pages(map, start, len, prot, pages, nr_pages); 204 if (count == -1) 205 return (-EFAULT); 206 207 for (i = 0; i != nr_pages; i++) { 208 struct page *pg = pages[i]; 209 210 vm_page_lock(pg); 211 vm_page_wire(pg); 212 vm_page_unhold(pg); 213 vm_page_unlock(pg); 214 } 215 return (nr_pages); 216 } 217 218 int 219 __get_user_pages_fast(unsigned long start, int nr_pages, int write, 220 struct page **pages) 221 { 222 vm_map_t map; 223 vm_page_t *mp; 224 vm_offset_t va; 225 vm_offset_t end; 226 vm_prot_t prot; 227 int count; 228 229 if (nr_pages == 0 || in_interrupt()) 230 return (0); 231 232 MPASS(pages != NULL); 233 va = start; 234 map = &curthread->td_proc->p_vmspace->vm_map; 235 end = start + (((size_t)nr_pages) << PAGE_SHIFT); 236 if (start < vm_map_min(map) || end > vm_map_max(map)) 237 return (-EINVAL); 238 prot = write ? (VM_PROT_READ | VM_PROT_WRITE) : VM_PROT_READ; 239 for (count = 0, mp = pages, va = start; va < end; 240 mp++, va += PAGE_SIZE, count++) { 241 *mp = pmap_extract_and_hold(map->pmap, va, prot); 242 if (*mp == NULL) 243 break; 244 245 vm_page_lock(*mp); 246 vm_page_wire(*mp); 247 vm_page_unhold(*mp); 248 vm_page_unlock(*mp); 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 268 get_user_pages_remote(struct task_struct *task, struct mm_struct *mm, 269 unsigned long start, unsigned long nr_pages, 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 280 get_user_pages(unsigned long start, unsigned long nr_pages, int gup_flags, 281 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 291 is_vmalloc_addr(const void *addr) 292 { 293 return (vtoslab((vm_offset_t)addr & ~UMA_SLAB_MASK) != NULL); 294 } 295 296 struct page * 297 linux_shmem_read_mapping_page_gfp(vm_object_t obj, int pindex, gfp_t gfp) 298 { 299 vm_page_t page; 300 int rv; 301 302 if ((gfp & GFP_NOWAIT) != 0) 303 panic("GFP_NOWAIT is unimplemented"); 304 305 VM_OBJECT_WLOCK(obj); 306 page = vm_page_grab(obj, pindex, VM_ALLOC_NORMAL | VM_ALLOC_NOBUSY | 307 VM_ALLOC_WIRED); 308 if (page->valid != VM_PAGE_BITS_ALL) { 309 vm_page_xbusy(page); 310 if (vm_pager_has_page(obj, pindex, NULL, NULL)) { 311 rv = vm_pager_get_pages(obj, &page, 1, NULL, NULL); 312 if (rv != VM_PAGER_OK) { 313 vm_page_lock(page); 314 vm_page_unwire(page, PQ_NONE); 315 vm_page_free(page); 316 vm_page_unlock(page); 317 VM_OBJECT_WUNLOCK(obj); 318 return (ERR_PTR(-EINVAL)); 319 } 320 MPASS(page->valid == VM_PAGE_BITS_ALL); 321 } else { 322 pmap_zero_page(page); 323 page->valid = VM_PAGE_BITS_ALL; 324 page->dirty = 0; 325 } 326 vm_page_xunbusy(page); 327 } 328 VM_OBJECT_WUNLOCK(obj); 329 return (page); 330 } 331 332 struct linux_file * 333 linux_shmem_file_setup(const char *name, loff_t size, unsigned long flags) 334 { 335 struct fileobj { 336 struct linux_file file __aligned(sizeof(void *)); 337 struct vnode vnode __aligned(sizeof(void *)); 338 }; 339 struct fileobj *fileobj; 340 struct linux_file *filp; 341 struct vnode *vp; 342 int error; 343 344 fileobj = kzalloc(sizeof(*fileobj), GFP_KERNEL); 345 if (fileobj == NULL) { 346 error = -ENOMEM; 347 goto err_0; 348 } 349 filp = &fileobj->file; 350 vp = &fileobj->vnode; 351 352 filp->f_count = 1; 353 filp->f_vnode = vp; 354 filp->f_shmem = vm_pager_allocate(OBJT_DEFAULT, NULL, size, 355 VM_PROT_READ | VM_PROT_WRITE, 0, curthread->td_ucred); 356 if (filp->f_shmem == NULL) { 357 error = -ENOMEM; 358 goto err_1; 359 } 360 return (filp); 361 err_1: 362 kfree(filp); 363 err_0: 364 return (ERR_PTR(error)); 365 } 366 367 static vm_ooffset_t 368 linux_invalidate_mapping_pages_sub(vm_object_t obj, vm_pindex_t start, 369 vm_pindex_t end, int flags) 370 { 371 int start_count, end_count; 372 373 VM_OBJECT_WLOCK(obj); 374 start_count = obj->resident_page_count; 375 vm_object_page_remove(obj, start, end, flags); 376 end_count = obj->resident_page_count; 377 VM_OBJECT_WUNLOCK(obj); 378 return (start_count - end_count); 379 } 380 381 unsigned long 382 linux_invalidate_mapping_pages(vm_object_t obj, pgoff_t start, pgoff_t end) 383 { 384 385 return (linux_invalidate_mapping_pages_sub(obj, start, end, OBJPR_CLEANONLY)); 386 } 387 388 void 389 linux_shmem_truncate_range(vm_object_t obj, loff_t lstart, loff_t lend) 390 { 391 vm_pindex_t start = OFF_TO_IDX(lstart + PAGE_SIZE - 1); 392 vm_pindex_t end = OFF_TO_IDX(lend + 1); 393 394 (void) linux_invalidate_mapping_pages_sub(obj, start, end, 0); 395 } 396