xref: /openbmc/linux/arch/arm64/include/asm/memory.h (revision 1ac731c529cd4d6adbce134754b51ff7d822b145)
1  /* SPDX-License-Identifier: GPL-2.0-only */
2  /*
3   * Based on arch/arm/include/asm/memory.h
4   *
5   * Copyright (C) 2000-2002 Russell King
6   * Copyright (C) 2012 ARM Ltd.
7   *
8   * Note: this file should not be included by non-asm/.h files
9   */
10  #ifndef __ASM_MEMORY_H
11  #define __ASM_MEMORY_H
12  
13  #include <linux/const.h>
14  #include <linux/sizes.h>
15  #include <asm/page-def.h>
16  
17  /*
18   * Size of the PCI I/O space. This must remain a power of two so that
19   * IO_SPACE_LIMIT acts as a mask for the low bits of I/O addresses.
20   */
21  #define PCI_IO_SIZE		SZ_16M
22  
23  /*
24   * VMEMMAP_SIZE - allows the whole linear region to be covered by
25   *                a struct page array
26   *
27   * If we are configured with a 52-bit kernel VA then our VMEMMAP_SIZE
28   * needs to cover the memory region from the beginning of the 52-bit
29   * PAGE_OFFSET all the way to PAGE_END for 48-bit. This allows us to
30   * keep a constant PAGE_OFFSET and "fallback" to using the higher end
31   * of the VMEMMAP where 52-bit support is not available in hardware.
32   */
33  #define VMEMMAP_SHIFT	(PAGE_SHIFT - STRUCT_PAGE_MAX_SHIFT)
34  #define VMEMMAP_SIZE	((_PAGE_END(VA_BITS_MIN) - PAGE_OFFSET) >> VMEMMAP_SHIFT)
35  
36  /*
37   * PAGE_OFFSET - the virtual address of the start of the linear map, at the
38   *               start of the TTBR1 address space.
39   * PAGE_END - the end of the linear map, where all other kernel mappings begin.
40   * KIMAGE_VADDR - the virtual address of the start of the kernel image.
41   * VA_BITS - the maximum number of bits for virtual addresses.
42   */
43  #define VA_BITS			(CONFIG_ARM64_VA_BITS)
44  #define _PAGE_OFFSET(va)	(-(UL(1) << (va)))
45  #define PAGE_OFFSET		(_PAGE_OFFSET(VA_BITS))
46  #define KIMAGE_VADDR		(MODULES_END)
47  #define MODULES_END		(MODULES_VADDR + MODULES_VSIZE)
48  #define MODULES_VADDR		(_PAGE_END(VA_BITS_MIN))
49  #define MODULES_VSIZE		(SZ_2G)
50  #define VMEMMAP_START		(-(UL(1) << (VA_BITS - VMEMMAP_SHIFT)))
51  #define VMEMMAP_END		(VMEMMAP_START + VMEMMAP_SIZE)
52  #define PCI_IO_END		(VMEMMAP_START - SZ_8M)
53  #define PCI_IO_START		(PCI_IO_END - PCI_IO_SIZE)
54  #define FIXADDR_TOP		(VMEMMAP_START - SZ_32M)
55  
56  #if VA_BITS > 48
57  #define VA_BITS_MIN		(48)
58  #else
59  #define VA_BITS_MIN		(VA_BITS)
60  #endif
61  
62  #define _PAGE_END(va)		(-(UL(1) << ((va) - 1)))
63  
64  #define KERNEL_START		_text
65  #define KERNEL_END		_end
66  
67  /*
68   * Generic and tag-based KASAN require 1/8th and 1/16th of the kernel virtual
69   * address space for the shadow region respectively. They can bloat the stack
70   * significantly, so double the (minimum) stack size when they are in use.
71   */
72  #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
73  #define KASAN_SHADOW_OFFSET	_AC(CONFIG_KASAN_SHADOW_OFFSET, UL)
74  #define KASAN_SHADOW_END	((UL(1) << (64 - KASAN_SHADOW_SCALE_SHIFT)) \
75  					+ KASAN_SHADOW_OFFSET)
76  #define PAGE_END		(KASAN_SHADOW_END - (1UL << (vabits_actual - KASAN_SHADOW_SCALE_SHIFT)))
77  #define KASAN_THREAD_SHIFT	1
78  #else
79  #define KASAN_THREAD_SHIFT	0
80  #define PAGE_END		(_PAGE_END(VA_BITS_MIN))
81  #endif /* CONFIG_KASAN */
82  
83  #define MIN_THREAD_SHIFT	(14 + KASAN_THREAD_SHIFT)
84  
85  /*
86   * VMAP'd stacks are allocated at page granularity, so we must ensure that such
87   * stacks are a multiple of page size.
88   */
89  #if defined(CONFIG_VMAP_STACK) && (MIN_THREAD_SHIFT < PAGE_SHIFT)
90  #define THREAD_SHIFT		PAGE_SHIFT
91  #else
92  #define THREAD_SHIFT		MIN_THREAD_SHIFT
93  #endif
94  
95  #if THREAD_SHIFT >= PAGE_SHIFT
96  #define THREAD_SIZE_ORDER	(THREAD_SHIFT - PAGE_SHIFT)
97  #endif
98  
99  #define THREAD_SIZE		(UL(1) << THREAD_SHIFT)
100  
101  /*
102   * By aligning VMAP'd stacks to 2 * THREAD_SIZE, we can detect overflow by
103   * checking sp & (1 << THREAD_SHIFT), which we can do cheaply in the entry
104   * assembly.
105   */
106  #ifdef CONFIG_VMAP_STACK
107  #define THREAD_ALIGN		(2 * THREAD_SIZE)
108  #else
109  #define THREAD_ALIGN		THREAD_SIZE
110  #endif
111  
112  #define IRQ_STACK_SIZE		THREAD_SIZE
113  
114  #define OVERFLOW_STACK_SIZE	SZ_4K
115  
116  /*
117   * With the minimum frame size of [x29, x30], exactly half the combined
118   * sizes of the hyp and overflow stacks is the maximum size needed to
119   * save the unwinded stacktrace; plus an additional entry to delimit the
120   * end.
121   */
122  #define NVHE_STACKTRACE_SIZE	((OVERFLOW_STACK_SIZE + PAGE_SIZE) / 2 + sizeof(long))
123  
124  /*
125   * Alignment of kernel segments (e.g. .text, .data).
126   *
127   *  4 KB granule:  16 level 3 entries, with contiguous bit
128   * 16 KB granule:   4 level 3 entries, without contiguous bit
129   * 64 KB granule:   1 level 3 entry
130   */
131  #define SEGMENT_ALIGN		SZ_64K
132  
133  /*
134   * Memory types available.
135   *
136   * IMPORTANT: MT_NORMAL must be index 0 since vm_get_page_prot() may 'or' in
137   *	      the MT_NORMAL_TAGGED memory type for PROT_MTE mappings. Note
138   *	      that protection_map[] only contains MT_NORMAL attributes.
139   */
140  #define MT_NORMAL		0
141  #define MT_NORMAL_TAGGED	1
142  #define MT_NORMAL_NC		2
143  #define MT_DEVICE_nGnRnE	3
144  #define MT_DEVICE_nGnRE		4
145  
146  /*
147   * Memory types for Stage-2 translation
148   */
149  #define MT_S2_NORMAL		0xf
150  #define MT_S2_DEVICE_nGnRE	0x1
151  
152  /*
153   * Memory types for Stage-2 translation when ID_AA64MMFR2_EL1.FWB is 0001
154   * Stage-2 enforces Normal-WB and Device-nGnRE
155   */
156  #define MT_S2_FWB_NORMAL	6
157  #define MT_S2_FWB_DEVICE_nGnRE	1
158  
159  #ifdef CONFIG_ARM64_4K_PAGES
160  #define IOREMAP_MAX_ORDER	(PUD_SHIFT)
161  #else
162  #define IOREMAP_MAX_ORDER	(PMD_SHIFT)
163  #endif
164  
165  /*
166   *  Open-coded (swapper_pg_dir - reserved_pg_dir) as this cannot be calculated
167   *  until link time.
168   */
169  #define RESERVED_SWAPPER_OFFSET	(PAGE_SIZE)
170  
171  /*
172   *  Open-coded (swapper_pg_dir - tramp_pg_dir) as this cannot be calculated
173   *  until link time.
174   */
175  #define TRAMP_SWAPPER_OFFSET	(2 * PAGE_SIZE)
176  
177  #ifndef __ASSEMBLY__
178  
179  #include <linux/bitops.h>
180  #include <linux/compiler.h>
181  #include <linux/mmdebug.h>
182  #include <linux/types.h>
183  #include <asm/boot.h>
184  #include <asm/bug.h>
185  
186  #if VA_BITS > 48
187  extern u64			vabits_actual;
188  #else
189  #define vabits_actual		((u64)VA_BITS)
190  #endif
191  
192  extern s64			memstart_addr;
193  /* PHYS_OFFSET - the physical address of the start of memory. */
194  #define PHYS_OFFSET		({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
195  
196  /* the virtual base of the kernel image */
197  extern u64			kimage_vaddr;
198  
199  /* the offset between the kernel virtual and physical mappings */
200  extern u64			kimage_voffset;
201  
kaslr_offset(void)202  static inline unsigned long kaslr_offset(void)
203  {
204  	return kimage_vaddr - KIMAGE_VADDR;
205  }
206  
207  #ifdef CONFIG_RANDOMIZE_BASE
208  void kaslr_init(void);
kaslr_enabled(void)209  static inline bool kaslr_enabled(void)
210  {
211  	extern bool __kaslr_is_enabled;
212  	return __kaslr_is_enabled;
213  }
214  #else
kaslr_init(void)215  static inline void kaslr_init(void) { }
kaslr_enabled(void)216  static inline bool kaslr_enabled(void) { return false; }
217  #endif
218  
219  /*
220   * Allow all memory at the discovery stage. We will clip it later.
221   */
222  #define MIN_MEMBLOCK_ADDR	0
223  #define MAX_MEMBLOCK_ADDR	U64_MAX
224  
225  /*
226   * PFNs are used to describe any physical page; this means
227   * PFN 0 == physical address 0.
228   *
229   * This is the PFN of the first RAM page in the kernel
230   * direct-mapped view.  We assume this is the first page
231   * of RAM in the mem_map as well.
232   */
233  #define PHYS_PFN_OFFSET	(PHYS_OFFSET >> PAGE_SHIFT)
234  
235  /*
236   * When dealing with data aborts, watchpoints, or instruction traps we may end
237   * up with a tagged userland pointer. Clear the tag to get a sane pointer to
238   * pass on to access_ok(), for instance.
239   */
240  #define __untagged_addr(addr)	\
241  	((__force __typeof__(addr))sign_extend64((__force u64)(addr), 55))
242  
243  #define untagged_addr(addr)	({					\
244  	u64 __addr = (__force u64)(addr);					\
245  	__addr &= __untagged_addr(__addr);				\
246  	(__force __typeof__(addr))__addr;				\
247  })
248  
249  #if defined(CONFIG_KASAN_SW_TAGS) || defined(CONFIG_KASAN_HW_TAGS)
250  #define __tag_shifted(tag)	((u64)(tag) << 56)
251  #define __tag_reset(addr)	__untagged_addr(addr)
252  #define __tag_get(addr)		(__u8)((u64)(addr) >> 56)
253  #else
254  #define __tag_shifted(tag)	0UL
255  #define __tag_reset(addr)	(addr)
256  #define __tag_get(addr)		0
257  #endif /* CONFIG_KASAN_SW_TAGS || CONFIG_KASAN_HW_TAGS */
258  
__tag_set(const void * addr,u8 tag)259  static inline const void *__tag_set(const void *addr, u8 tag)
260  {
261  	u64 __addr = (u64)addr & ~__tag_shifted(0xff);
262  	return (const void *)(__addr | __tag_shifted(tag));
263  }
264  
265  #ifdef CONFIG_KASAN_HW_TAGS
266  #define arch_enable_tag_checks_sync()		mte_enable_kernel_sync()
267  #define arch_enable_tag_checks_async()		mte_enable_kernel_async()
268  #define arch_enable_tag_checks_asymm()		mte_enable_kernel_asymm()
269  #define arch_suppress_tag_checks_start()	mte_enable_tco()
270  #define arch_suppress_tag_checks_stop()		mte_disable_tco()
271  #define arch_force_async_tag_fault()		mte_check_tfsr_exit()
272  #define arch_get_random_tag()			mte_get_random_tag()
273  #define arch_get_mem_tag(addr)			mte_get_mem_tag(addr)
274  #define arch_set_mem_tag_range(addr, size, tag, init)	\
275  			mte_set_mem_tag_range((addr), (size), (tag), (init))
276  #endif /* CONFIG_KASAN_HW_TAGS */
277  
278  /*
279   * Physical vs virtual RAM address space conversion.  These are
280   * private definitions which should NOT be used outside memory.h
281   * files.  Use virt_to_phys/phys_to_virt/__pa/__va instead.
282   */
283  
284  
285  /*
286   * Check whether an arbitrary address is within the linear map, which
287   * lives in the [PAGE_OFFSET, PAGE_END) interval at the bottom of the
288   * kernel's TTBR1 address range.
289   */
290  #define __is_lm_address(addr)	(((u64)(addr) - PAGE_OFFSET) < (PAGE_END - PAGE_OFFSET))
291  
292  #define __lm_to_phys(addr)	(((addr) - PAGE_OFFSET) + PHYS_OFFSET)
293  #define __kimg_to_phys(addr)	((addr) - kimage_voffset)
294  
295  #define __virt_to_phys_nodebug(x) ({					\
296  	phys_addr_t __x = (phys_addr_t)(__tag_reset(x));		\
297  	__is_lm_address(__x) ? __lm_to_phys(__x) : __kimg_to_phys(__x);	\
298  })
299  
300  #define __pa_symbol_nodebug(x)	__kimg_to_phys((phys_addr_t)(x))
301  
302  #ifdef CONFIG_DEBUG_VIRTUAL
303  extern phys_addr_t __virt_to_phys(unsigned long x);
304  extern phys_addr_t __phys_addr_symbol(unsigned long x);
305  #else
306  #define __virt_to_phys(x)	__virt_to_phys_nodebug(x)
307  #define __phys_addr_symbol(x)	__pa_symbol_nodebug(x)
308  #endif /* CONFIG_DEBUG_VIRTUAL */
309  
310  #define __phys_to_virt(x)	((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET)
311  #define __phys_to_kimg(x)	((unsigned long)((x) + kimage_voffset))
312  
313  /*
314   * Convert a page to/from a physical address
315   */
316  #define page_to_phys(page)	(__pfn_to_phys(page_to_pfn(page)))
317  #define phys_to_page(phys)	(pfn_to_page(__phys_to_pfn(phys)))
318  
319  /*
320   * Note: Drivers should NOT use these.  They are the wrong
321   * translation for translating DMA addresses.  Use the driver
322   * DMA support - see dma-mapping.h.
323   */
324  #define virt_to_phys virt_to_phys
virt_to_phys(const volatile void * x)325  static inline phys_addr_t virt_to_phys(const volatile void *x)
326  {
327  	return __virt_to_phys((unsigned long)(x));
328  }
329  
330  #define phys_to_virt phys_to_virt
phys_to_virt(phys_addr_t x)331  static inline void *phys_to_virt(phys_addr_t x)
332  {
333  	return (void *)(__phys_to_virt(x));
334  }
335  
336  /* Needed already here for resolving __phys_to_pfn() in virt_to_pfn() */
337  #include <asm-generic/memory_model.h>
338  
virt_to_pfn(const void * kaddr)339  static inline unsigned long virt_to_pfn(const void *kaddr)
340  {
341  	return __phys_to_pfn(virt_to_phys(kaddr));
342  }
343  
344  /*
345   * Drivers should NOT use these either.
346   */
347  #define __pa(x)			__virt_to_phys((unsigned long)(x))
348  #define __pa_symbol(x)		__phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0))
349  #define __pa_nodebug(x)		__virt_to_phys_nodebug((unsigned long)(x))
350  #define __va(x)			((void *)__phys_to_virt((phys_addr_t)(x)))
351  #define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)
352  #define sym_to_pfn(x)		__phys_to_pfn(__pa_symbol(x))
353  
354  /*
355   *  virt_to_page(x)	convert a _valid_ virtual address to struct page *
356   *  virt_addr_valid(x)	indicates whether a virtual address is valid
357   */
358  #define ARCH_PFN_OFFSET		((unsigned long)PHYS_PFN_OFFSET)
359  
360  #if defined(CONFIG_DEBUG_VIRTUAL)
361  #define page_to_virt(x)	({						\
362  	__typeof__(x) __page = x;					\
363  	void *__addr = __va(page_to_phys(__page));			\
364  	(void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\
365  })
366  #define virt_to_page(x)		pfn_to_page(virt_to_pfn(x))
367  #else
368  #define page_to_virt(x)	({						\
369  	__typeof__(x) __page = x;					\
370  	u64 __idx = ((u64)__page - VMEMMAP_START) / sizeof(struct page);\
371  	u64 __addr = PAGE_OFFSET + (__idx * PAGE_SIZE);			\
372  	(void *)__tag_set((const void *)__addr, page_kasan_tag(__page));\
373  })
374  
375  #define virt_to_page(x)	({						\
376  	u64 __idx = (__tag_reset((u64)x) - PAGE_OFFSET) / PAGE_SIZE;	\
377  	u64 __addr = VMEMMAP_START + (__idx * sizeof(struct page));	\
378  	(struct page *)__addr;						\
379  })
380  #endif /* CONFIG_DEBUG_VIRTUAL */
381  
382  #define virt_addr_valid(addr)	({					\
383  	__typeof__(addr) __addr = __tag_reset(addr);			\
384  	__is_lm_address(__addr) && pfn_is_map_memory(virt_to_pfn(__addr));	\
385  })
386  
387  void dump_mem_limit(void);
388  #endif /* !ASSEMBLY */
389  
390  /*
391   * Given that the GIC architecture permits ITS implementations that can only be
392   * configured with a LPI table address once, GICv3 systems with many CPUs may
393   * end up reserving a lot of different regions after a kexec for their LPI
394   * tables (one per CPU), as we are forced to reuse the same memory after kexec
395   * (and thus reserve it persistently with EFI beforehand)
396   */
397  #if defined(CONFIG_EFI) && defined(CONFIG_ARM_GIC_V3_ITS)
398  # define INIT_MEMBLOCK_RESERVED_REGIONS	(INIT_MEMBLOCK_REGIONS + NR_CPUS + 1)
399  #endif
400  
401  /*
402   * memory regions which marked with flag MEMBLOCK_NOMAP(for example, the memory
403   * of the EFI_UNUSABLE_MEMORY type) may divide a continuous memory block into
404   * multiple parts. As a result, the number of memory regions is large.
405   */
406  #ifdef CONFIG_EFI
407  #define INIT_MEMBLOCK_MEMORY_REGIONS	(INIT_MEMBLOCK_REGIONS * 8)
408  #endif
409  
410  #include <asm-generic/memory_model.h>
411  
412  #endif /* __ASM_MEMORY_H */
413