sys/compat/linuxkpi/common/src/linux_page.c

   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 }