1 /*
2 * Copyright (c) 2000-2020 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28 /*
29 * @OSF_COPYRIGHT@
30 */
31 /*
32 * Mach Operating System
33 * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
34 * All Rights Reserved.
35 *
36 * Permission to use, copy, modify and distribute this software and its
37 * documentation is hereby granted, provided that both the copyright
38 * notice and this permission notice appear in all copies of the
39 * software, derivative works or modified versions, and any portions
40 * thereof, and that both notices appear in supporting documentation.
41 *
42 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
43 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
44 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
45 *
46 * Carnegie Mellon requests users of this software to return to
47 *
48 * Software Distribution Coordinator or [email protected]
49 * School of Computer Science
50 * Carnegie Mellon University
51 * Pittsburgh PA 15213-3890
52 *
53 * any improvements or extensions that they make and grant Carnegie Mellon
54 * the rights to redistribute these changes.
55 */
56 /*
57 */
58 /*
59 * File: mach/vm_param.h
60 * Author: Avadis Tevanian, Jr., Michael Wayne Young
61 * Date: 1985
62 *
63 * Machine independent virtual memory parameters.
64 *
65 */
66
67 #ifndef _MACH_VM_PARAM_H_
68 #define _MACH_VM_PARAM_H_
69
70 #include <mach/machine/vm_param.h>
71
72 #ifdef KERNEL
73
74 #ifndef ASSEMBLER
75 #include <mach/vm_types.h>
76 #endif /* ASSEMBLER */
77
78 #include <os/base.h>
79 #include <os/overflow.h>
80
81 /*
82 * The machine independent pages are refered to as PAGES. A page
83 * is some number of hardware pages, depending on the target machine.
84 */
85
86 #ifndef ASSEMBLER
87
88 #define PAGE_SIZE_64 (unsigned long long)PAGE_SIZE /* pagesize in addr units */
89 #define PAGE_MASK_64 (unsigned long long)PAGE_MASK /* mask for off in page */
90
91 /*
92 * Convert addresses to pages and vice versa. No rounding is used.
93 * The atop_32 and ptoa_32 macros should not be use on 64 bit types.
94 * The round_page_64 and trunc_page_64 macros should be used instead.
95 */
96
97 #define atop_32(x) ((uint32_t)(x) >> PAGE_SHIFT)
98 #define ptoa_32(x) ((uint32_t)(x) << PAGE_SHIFT)
99 #define atop_64(x) ((uint64_t)(x) >> PAGE_SHIFT)
100 #define ptoa_64(x) ((uint64_t)(x) << PAGE_SHIFT)
101
102 #define atop_kernel(x) ((vm_address_t)(x) >> PAGE_SHIFT)
103 #define ptoa_kernel(x) ((vm_address_t)(x) << PAGE_SHIFT)
104
105 /*
106 * While the following block is enabled, the legacy atop and ptoa
107 * macros will behave correctly. If not, they will generate
108 * invalid lvalue errors.
109 */
110
111 #if 1
112 #define atop(x) ((vm_address_t)(x) >> PAGE_SHIFT)
113 #define ptoa(x) ((vm_address_t)(x) << PAGE_SHIFT)
114 #else
115 #define atop(x) (0UL = 0)
116 #define ptoa(x) (0UL = 0)
117 #endif
118
119 /*
120 * Page-size rounding macros for the Public fixed-width VM types.
121 */
122 #define mach_vm_round_page(x) (((mach_vm_offset_t)(x) + PAGE_MASK) & ~((signed)PAGE_MASK))
123 #define mach_vm_trunc_page(x) ((mach_vm_offset_t)(x) & ~((signed)PAGE_MASK))
124
125 #define round_page_overflow(in, out) __os_warn_unused(({ \
126 bool __ovr = os_add_overflow(in, (__typeof__(*out))PAGE_MASK, out); \
127 *out &= ~((__typeof__(*out))PAGE_MASK); \
128 __ovr; \
129 }))
130
131 static inline int OS_WARN_RESULT
mach_vm_round_page_overflow(mach_vm_offset_t in,mach_vm_offset_t * out)132 mach_vm_round_page_overflow(mach_vm_offset_t in, mach_vm_offset_t *out)
133 {
134 return round_page_overflow(in, out);
135 }
136
137 #define memory_object_round_page(x) (((memory_object_offset_t)(x) + PAGE_MASK) & ~((signed)PAGE_MASK))
138 #define memory_object_trunc_page(x) ((memory_object_offset_t)(x) & ~((signed)PAGE_MASK))
139
140 /*
141 * Rounding macros for the legacy (scalable with the current task's
142 * address space size) VM types.
143 */
144
145 #define round_page(x) (((vm_offset_t)(x) + PAGE_MASK) & ~((vm_offset_t)PAGE_MASK))
146 #define trunc_page(x) ((vm_offset_t)(x) & ~((vm_offset_t)PAGE_MASK))
147
148 /*
149 * Round off or truncate to the nearest page. These will work
150 * for either addresses or counts. (i.e. 1 byte rounds to 1 page
151 * bytes. The round_page_32 and trunc_page_32 macros should not be
152 * use on 64 bit types. The round_page_64 and trunc_page_64 macros
153 * should be used instead.
154 *
155 * These should only be used in the rare case the size of the address
156 * or length is hard-coded as 32 or 64 bit. Otherwise, the macros
157 * associated with the specific VM type should be used.
158 */
159
160 #define round_page_32(x) (((uint32_t)(x) + PAGE_MASK) & ~((uint32_t)PAGE_MASK))
161 #define trunc_page_32(x) ((uint32_t)(x) & ~((uint32_t)PAGE_MASK))
162 #define round_page_64(x) (((uint64_t)(x) + PAGE_MASK_64) & ~((uint64_t)PAGE_MASK_64))
163 #define trunc_page_64(x) ((uint64_t)(x) & ~((uint64_t)PAGE_MASK_64))
164
165 #define round_page_mask_32(x, mask) (((uint32_t)(x) + (mask)) & ~((uint32_t)(mask)))
166 #define trunc_page_mask_32(x, mask) ((uint32_t)(x) & ~((uint32_t)(mask)))
167 #define round_page_mask_64(x, mask) (((uint64_t)(x) + (mask)) & ~((uint64_t)(mask)))
168 #define trunc_page_mask_64(x, mask) ((uint64_t)(x) & ~((uint64_t)(mask)))
169
170 /*
171 * Enable the following block to find uses of xxx_32 macros that should
172 * be xxx_64. These macros only work in C code, not C++. The resulting
173 * binaries are not functional. Look for invalid lvalue errors in
174 * the compiler output.
175 *
176 * Enabling the following block will also find use of the xxx_64 macros
177 * that have been passed pointers. The parameters should be case to an
178 * unsigned long type first. Look for invalid operands to binary + error
179 * in the compiler output.
180 */
181
182 #if 0
183 #undef atop_32
184 #undef ptoa_32
185 #undef round_page_32
186 #undef trunc_page_32
187 #undef atop_64
188 #undef ptoa_64
189 #undef round_page_64
190 #undef trunc_page_64
191
192 #ifndef __cplusplus
193
194 #define atop_32(x) \
195 (__builtin_choose_expr (sizeof(x) != sizeof(uint64_t), \
196 (*(long *)0), \
197 (0UL)) = 0)
198
199 #define ptoa_32(x) \
200 (__builtin_choose_expr (sizeof(x) != sizeof(uint64_t), \
201 (*(long *)0), \
202 (0UL)) = 0)
203
204 #define round_page_32(x) \
205 (__builtin_choose_expr (sizeof(x) != sizeof(uint64_t), \
206 (*(long *)0), \
207 (0UL)) = 0)
208
209 #define trunc_page_32(x) \
210 (__builtin_choose_expr (sizeof(x) != sizeof(uint64_t), \
211 (*(long *)0), \
212 (0UL)) = 0)
213 #else
214
215 #define atop_32(x) (0)
216 #define ptoa_32(x) (0)
217 #define round_page_32(x) (0)
218 #define trunc_page_32(x) (0)
219
220 #endif /* ! __cplusplus */
221
222 #define atop_64(x) ((uint64_t)((x) + (uint8_t *)0))
223 #define ptoa_64(x) ((uint64_t)((x) + (uint8_t *)0))
224 #define round_page_64(x) ((uint64_t)((x) + (uint8_t *)0))
225 #define trunc_page_64(x) ((uint64_t)((x) + (uint8_t *)0))
226
227 #endif
228
229 /*
230 * Determine whether an address is page-aligned, or a count is
231 * an exact page multiple.
232 */
233
234 #define page_aligned(x) (((x) & PAGE_MASK) == 0)
235
236 extern vm_size_t mem_size; /* 32-bit size of memory - limited by maxmem - deprecated */
237 extern uint64_t max_mem; /* 64-bit size of memory - limited by maxmem */
238
239 /*
240 * The default pager does not handle 64-bit offsets inside its objects,
241 * so this limits the size of anonymous memory objects to 4GB minus 1 page.
242 * When we need to allocate a chunk of anonymous memory over that size,
243 * we have to allocate more than one chunk.
244 */
245 #define ANON_MAX_SIZE ((1ULL << 32) - PAGE_SIZE)
246 /*
247 * Work-around for <rdar://problem/6626493>
248 * Break large anonymous memory areas into 128MB chunks to alleviate
249 * the cost of copying when copy-on-write is not possible because a small
250 * portion of it being wired.
251 */
252 #define ANON_CHUNK_SIZE (128ULL * 1024 * 1024) /* 128MB */
253
254 /*
255 * The 'medium' malloc allocator would like its regions
256 * to be chunked up into MALLOC_MEDIUM_CHUNK_SIZE chunks
257 * and backed by different objects. This avoids contention
258 * on a single large object and showed solid improvements on high
259 * core machines with workloads involving video and graphics processing.
260 */
261 #define MALLOC_MEDIUM_CHUNK_SIZE (8ULL * 1024 * 1024) /* 8 MB */
262
263 #ifdef KERNEL_PRIVATE
264 extern uint64_t sane_size; /* Memory size to use for defaults calculations */
265 #endif /* KERNEL_PRIVATE */
266
267 #ifdef XNU_KERNEL_PRIVATE
268
269 #include <kern/debug.h>
270
271 extern uint64_t mem_actual; /* 64-bit size of memory - not limited by maxmem */
272 extern uint64_t max_mem_actual; /* Size of physical memory adjusted by maxmem */
273 extern addr64_t vm_last_addr; /* Highest kernel virtual address known to the VM system */
274
275 extern const vm_offset_t vm_min_kernel_address;
276 extern const vm_offset_t vm_max_kernel_address;
277
278 extern vm_offset_t vm_kernel_stext;
279 extern vm_offset_t vm_kernel_etext;
280 extern vm_offset_t vm_kernel_slid_base;
281 extern vm_offset_t vm_kernel_slid_top;
282 extern vm_offset_t vm_kernel_slide;
283 extern vm_offset_t vm_kernel_addrperm;
284 extern vm_offset_t vm_kext_base;
285 extern vm_offset_t vm_kext_top;
286 extern vm_offset_t vm_kernel_base;
287 extern vm_offset_t vm_kernel_top;
288 extern vm_offset_t vm_hib_base;
289
290 extern vm_offset_t vm_kernel_builtinkmod_text;
291 extern vm_offset_t vm_kernel_builtinkmod_text_end;
292
293 #define VM_KERNEL_IS_SLID(_o) \
294 (((vm_offset_t)VM_KERNEL_STRIP_PTR(_o) >= vm_kernel_slid_base) && \
295 ((vm_offset_t)VM_KERNEL_STRIP_PTR(_o) < vm_kernel_slid_top))
296
297 #define VM_KERNEL_SLIDE(_u) ((vm_offset_t)(_u) + vm_kernel_slide)
298
299 /*
300 * The following macros are to be used when exposing kernel addresses to
301 * userspace via any of the various debug or info facilities that might exist
302 * (e.g. stackshot, proc_info syscall, etc.). It is important to understand
303 * the goal of each macro and choose the right one depending on what you are
304 * trying to do. Misuse of these macros can result in critical data leaks
305 * which in turn lead to all sorts of system vulnerabilities. It is invalid to
306 * call these macros on a non-kernel address (NULL is allowed).
307 *
308 * VM_KERNEL_UNSLIDE:
309 * Use this macro when you are exposing an address to userspace which is
310 * *guaranteed* to be a "static" kernel or kext address (i.e. coming from text
311 * or data sections). These are the addresses which get "slid" via ASLR on
312 * kernel or kext load, and it's precisely the slide value we are trying to
313 * protect from userspace.
314 *
315 * VM_KERNEL_ADDRHIDE:
316 * Use when exposing an address for internal purposes: debugging, tracing,
317 * etc. The address will be unslid if necessary. Other addresses will be
318 * hidden on customer builds, and unmodified on internal builds.
319 *
320 * VM_KERNEL_ADDRHASH:
321 * Use this macro when exposing a kernel address to userspace on customer
322 * builds. The address can be from the static kernel or kext regions, or the
323 * kernel heap. The address will be unslid or hashed as appropriate.
324 *
325 *
326 * ** SECURITY WARNING: The following macros can leak kernel secrets.
327 * Use *only* in performance *critical* code.
328 *
329 * VM_KERNEL_ADDRPERM:
330 * VM_KERNEL_UNSLIDE_OR_PERM:
331 * Use these macros when exposing a kernel address to userspace on customer
332 * builds. The address can be from the static kernel or kext regions, or the
333 * kernel heap. The address will be unslid or permuted as appropriate.
334 *
335 * Nesting of these macros should be considered invalid.
336 */
337
338 #define __DO_UNSLIDE(_v) ((vm_offset_t)VM_KERNEL_STRIP_PTR(_v) - vm_kernel_slide)
339
340 #if DEBUG || DEVELOPMENT
341 #define VM_KERNEL_ADDRHIDE(_v) (VM_KERNEL_IS_SLID(_v) ? __DO_UNSLIDE(_v) : (vm_address_t)VM_KERNEL_STRIP_PTR(_v))
342 #else
343 #define VM_KERNEL_ADDRHIDE(_v) (VM_KERNEL_IS_SLID(_v) ? __DO_UNSLIDE(_v) : (vm_address_t)0)
344 #endif /* DEBUG || DEVELOPMENT */
345
346 #define VM_KERNEL_ADDRHASH(_v) vm_kernel_addrhash((vm_offset_t)(_v))
347
348 #define VM_KERNEL_UNSLIDE_OR_PERM(_v) ({ \
349 VM_KERNEL_IS_SLID(_v) ? __DO_UNSLIDE(_v) : \
350 VM_KERNEL_ADDRESS(_v) ? ((vm_offset_t)VM_KERNEL_STRIP_PTR(_v) + vm_kernel_addrperm) : \
351 (vm_offset_t)VM_KERNEL_STRIP_PTR(_v); \
352 })
353
354 #define VM_KERNEL_UNSLIDE(_v) ({ \
355 VM_KERNEL_IS_SLID(_v) ? __DO_UNSLIDE(_v) : (vm_offset_t)0; \
356 })
357
358 #define VM_KERNEL_ADDRPERM(_v) VM_KERNEL_UNSLIDE_OR_PERM(_v)
359
360 #undef mach_vm_round_page
361 #undef round_page
362 #undef round_page_32
363 #undef round_page_64
364
365 static inline mach_vm_offset_t
mach_vm_round_page(mach_vm_offset_t x)366 mach_vm_round_page(mach_vm_offset_t x)
367 {
368 if (round_page_overflow(x, &x)) {
369 panic("overflow detected");
370 }
371 return x;
372 }
373
374 static inline vm_offset_t
round_page(vm_offset_t x)375 round_page(vm_offset_t x)
376 {
377 if (round_page_overflow(x, &x)) {
378 panic("overflow detected");
379 }
380 return x;
381 }
382
383 static inline mach_vm_offset_t
round_page_64(mach_vm_offset_t x)384 round_page_64(mach_vm_offset_t x)
385 {
386 if (round_page_overflow(x, &x)) {
387 panic("overflow detected");
388 }
389 return x;
390 }
391
392 static inline uint32_t
round_page_32(uint32_t x)393 round_page_32(uint32_t x)
394 {
395 if (round_page_overflow(x, &x)) {
396 panic("overflow detected");
397 }
398 return x;
399 }
400
401
402 /*!
403 * @typedef vm_packing_params_t
404 *
405 * @brief
406 * Data structure representing the packing parameters for a given packed pointer
407 * encoding.
408 *
409 * @discussion
410 * Several data structures wish to pack their pointers on less than 64bits
411 * on LP64 in order to save memory.
412 *
413 * Adopters are supposed to define 3 macros:
414 * - @c *_BITS: number of storage bits used for the packing,
415 * - @c *_SHIFT: number of non significant low bits (expected to be 0),
416 * - @c *_BASE: the base against which to encode.
417 *
418 * The encoding is a no-op when @c *_BITS is equal to @c __WORDSIZE and
419 * @c *_SHIFT is 0.
420 *
421 *
422 * The convenience macro @c VM_PACKING_PARAMS can be used to create
423 * a @c vm_packing_params_t structure out of those definitions.
424 *
425 * It is customary to declare a constant global per scheme for the sake
426 * of debuggers to be able to dynamically decide how to unpack various schemes.
427 *
428 *
429 * This uses 2 possible schemes (who both preserve @c NULL):
430 *
431 * 1. When the storage bits and shift are sufficiently large (strictly more than
432 * VM_KERNEL_POINTER_SIGNIFICANT_BITS), a sign-extension scheme can be used.
433 *
434 * This allows to represent any kernel pointer.
435 *
436 * 2. Else, a base-relative scheme can be used, typical bases are:
437 *
438 * - @c KERNEL_PMAP_HEAP_RANGE_START when only pointers to heap (zone)
439 * allocated objects need to be packed,
440 *
441 * - @c VM_MIN_KERNEL_AND_KEXT_ADDRESS when pointers to kernel globals also
442 * need this.
443 *
444 * When such an ecoding is used, @c zone_restricted_va_max() must be taught
445 * about it.
446 */
447 typedef struct vm_packing_params {
448 vm_offset_t vmpp_base;
449 uint8_t vmpp_bits;
450 uint8_t vmpp_shift;
451 bool vmpp_base_relative;
452 } vm_packing_params_t;
453
454
455 /*!
456 * @macro VM_PACKING_IS_BASE_RELATIVE
457 *
458 * @brief
459 * Whether the packing scheme with those parameters will be base-relative.
460 */
461 #define VM_PACKING_IS_BASE_RELATIVE(ns) \
462 (ns##_BITS + ns##_SHIFT <= VM_KERNEL_POINTER_SIGNIFICANT_BITS)
463
464
465 /*!
466 * @macro VM_PACKING_PARAMS
467 *
468 * @brief
469 * Constructs a @c vm_packing_params_t structure based on the convention that
470 * macros with the @c _BASE, @c _BITS and @c _SHIFT suffixes have been defined
471 * to the proper values.
472 */
473 #define VM_PACKING_PARAMS(ns) \
474 (vm_packing_params_t){ \
475 .vmpp_base = ns##_BASE, \
476 .vmpp_bits = ns##_BITS, \
477 .vmpp_shift = ns##_SHIFT, \
478 .vmpp_base_relative = VM_PACKING_IS_BASE_RELATIVE(ns), \
479 }
480
481 /**
482 * @function vm_pack_pointer
483 *
484 * @brief
485 * Packs a pointer according to the specified parameters.
486 *
487 * @discussion
488 * The convenience @c VM_PACK_POINTER macro allows to synthesize
489 * the @c params argument.
490 *
491 * @param ptr The pointer to pack.
492 * @param params The encoding parameters.
493 * @returns The packed pointer.
494 */
495 static inline vm_offset_t
vm_pack_pointer(vm_offset_t ptr,vm_packing_params_t params)496 vm_pack_pointer(vm_offset_t ptr, vm_packing_params_t params)
497 {
498 if (!params.vmpp_base_relative) {
499 return ptr >> params.vmpp_shift;
500 }
501 if (ptr) {
502 return (ptr - params.vmpp_base) >> params.vmpp_shift;
503 }
504 return (vm_offset_t)0;
505 }
506 #define VM_PACK_POINTER(ptr, ns) \
507 vm_pack_pointer(ptr, VM_PACKING_PARAMS(ns))
508
509 /**
510 * @function vm_unpack_pointer
511 *
512 * @brief
513 * Unpacks a pointer packed with @c vm_pack_pointer().
514 *
515 * @discussion
516 * The convenience @c VM_UNPACK_POINTER macro allows to synthesize
517 * the @c params argument.
518 *
519 * @param packed The packed value to decode.
520 * @param params The encoding parameters.
521 * @returns The unpacked pointer.
522 */
523 static inline vm_offset_t
vm_unpack_pointer(vm_offset_t packed,vm_packing_params_t params)524 vm_unpack_pointer(vm_offset_t packed, vm_packing_params_t params)
525 {
526 if (!params.vmpp_base_relative) {
527 intptr_t addr = (intptr_t)packed;
528 addr <<= __WORDSIZE - params.vmpp_bits;
529 addr >>= __WORDSIZE - params.vmpp_bits - params.vmpp_shift;
530 return (vm_offset_t)addr;
531 }
532 if (packed) {
533 return (packed << params.vmpp_shift) + params.vmpp_base;
534 }
535 return (vm_offset_t)0;
536 }
537 #define VM_UNPACK_POINTER(packed, ns) \
538 vm_unpack_pointer(packed, VM_PACKING_PARAMS(ns))
539
540 /**
541 * @function vm_packing_max_packable
542 *
543 * @brief
544 * Returns the largest packable address for the given parameters.
545 *
546 * @discussion
547 * The convenience @c VM_PACKING_MAX_PACKABLE macro allows to synthesize
548 * the @c params argument.
549 *
550 * @param params The encoding parameters.
551 * @returns The largest packable pointer.
552 */
553 static inline vm_offset_t
vm_packing_max_packable(vm_packing_params_t params)554 vm_packing_max_packable(vm_packing_params_t params)
555 {
556 if (!params.vmpp_base_relative) {
557 return VM_MAX_KERNEL_ADDRESS;
558 }
559
560 vm_offset_t ptr = params.vmpp_base +
561 (((1ul << params.vmpp_bits) - 1) << params.vmpp_shift);
562
563 return ptr >= params.vmpp_base ? ptr : VM_MAX_KERNEL_ADDRESS;
564 }
565 #define VM_PACKING_MAX_PACKABLE(ns) \
566 vm_packing_max_packable(VM_PACKING_PARAMS(ns))
567
568
569 __abortlike
570 extern void
571 vm_packing_pointer_invalid(vm_offset_t ptr, vm_packing_params_t params);
572
573 /**
574 * @function vm_verify_pointer_packable
575 *
576 * @brief
577 * Panics if the specified pointer cannot be packed with the specified
578 * parameters.
579 *
580 * @discussion
581 * The convenience @c VM_VERIFY_POINTER_PACKABLE macro allows to synthesize
582 * the @c params argument.
583 *
584 * The convenience @c VM_ASSERT_POINTER_PACKABLE macro allows to synthesize
585 * the @c params argument, and is erased when assertions are disabled.
586 *
587 * @param ptr The packed value to decode.
588 * @param params The encoding parameters.
589 */
590 static inline void
vm_verify_pointer_packable(vm_offset_t ptr,vm_packing_params_t params)591 vm_verify_pointer_packable(vm_offset_t ptr, vm_packing_params_t params)
592 {
593 if (ptr & ((1ul << params.vmpp_shift) - 1)) {
594 vm_packing_pointer_invalid(ptr, params);
595 }
596 if (!params.vmpp_base_relative || ptr == 0) {
597 return;
598 }
599 if (ptr <= params.vmpp_base || ptr > vm_packing_max_packable(params)) {
600 vm_packing_pointer_invalid(ptr, params);
601 }
602 }
603 #define VM_VERIFY_POINTER_PACKABLE(ptr, ns) \
604 vm_verify_pointer_packable(ptr, VM_PACKING_PARAMS(ns))
605
606 #if DEBUG || DEVELOPMENT
607 #define VM_ASSERT_POINTER_PACKABLE(ptr, ns) \
608 VM_VERIFY_POINTER_PACKABLE(ptr, ns)
609 #else
610 #define VM_ASSERT_POINTER_PACKABLE(ptr, ns) ((void)(ptr))
611 #endif
612
613 /**
614 * @function vm_verify_pointer_range
615 *
616 * @brief
617 * Panics if some pointers in the specified range can't be packed with the
618 * specified parameters.
619 *
620 * @param subsystem The subsystem requiring the packing.
621 * @param min_address The smallest address of the range.
622 * @param max_address The largest address of the range.
623 * @param params The encoding parameters.
624 */
625 extern void
626 vm_packing_verify_range(
627 const char *subsystem,
628 vm_offset_t min_address,
629 vm_offset_t max_address,
630 vm_packing_params_t params);
631
632 #endif /* XNU_KERNEL_PRIVATE */
633
634 extern vm_size_t page_size;
635 extern vm_size_t page_mask;
636 extern int page_shift;
637
638 /* We need a way to get rid of compiler warnings when we cast from */
639 /* a 64 bit value to an address (which may be 32 bits or 64-bits). */
640 /* An intptr_t is used convert the value to the right precision, and */
641 /* then to an address. This macro is also used to convert addresses */
642 /* to 32-bit integers, which is a hard failure for a 64-bit kernel */
643 #include <stdint.h>
644 #ifndef __CAST_DOWN_CHECK
645 #define __CAST_DOWN_CHECK
646
647 #define CAST_DOWN( type, addr ) \
648 ( ((type)((uintptr_t) (addr)/(sizeof(type) < sizeof(uintptr_t) ? 0 : 1))) )
649
650 #define CAST_DOWN_EXPLICIT( type, addr ) ( ((type)((uintptr_t) (addr))) )
651
652 #endif /* __CAST_DOWN_CHECK */
653
654 #endif /* ASSEMBLER */
655
656 #endif /* KERNEL */
657
658 #endif /* _MACH_VM_PARAM_H_ */
659