xref: /haiku/src/system/boot/platform/efi/mmu.cpp (revision 46b7da1f4f40f7157d74fc7fb26ff9ec7f2416f2)
1 /*
2  * Copyright 2016-2022 Haiku, Inc. All rights reserved.
3  * Copyright 2014, Jessica Hamilton, jessica.l.hamilton@gmail.com.
4  * Copyright 2014, Henry Harrington, henry.harrington@gmail.com.
5  * Distributed under the terms of the MIT License.
6  */
7 
8 
9 #include <algorithm>
10 
11 #include <boot/addr_range.h>
12 #include <boot/platform.h>
13 #include <boot/stage2.h>
14 #include <kernel/kernel.h>
15 
16 #include "efi_platform.h"
17 #include "mmu.h"
18 
19 
20 //#define TRACE_MMU
21 #ifdef TRACE_MMU
22 #   define TRACE(x...) dprintf("efi/mmu: " x)
23 #else
24 #   define TRACE(x...) ;
25 #endif
26 
27 
28 struct memory_region {
29 	memory_region *next;
30 	addr_t vaddr;
31 	phys_addr_t paddr;
32 	size_t size;
33 
dprintmemory_region34 	void dprint(const char * msg) {
35  	  dprintf("%s memory_region v: %#" B_PRIxADDR " p: %#" B_PRIxPHYSADDR " size: %lu\n", msg, vaddr,
36 			paddr, size);
37 	}
38 
matchesmemory_region39 	bool matches(phys_addr_t expected_paddr, size_t expected_size) {
40 		return paddr == expected_paddr && size == expected_size;
41 	}
42 };
43 
44 
45 static addr_t sNextVirtualAddress = KERNEL_LOAD_BASE + 32 * 1024 * 1024;
46 static memory_region *allocated_regions = NULL;
47 
48 
49 extern "C" phys_addr_t
mmu_allocate_page()50 mmu_allocate_page()
51 {
52 	TRACE("%s: called\n", __func__);
53 
54 	efi_physical_addr addr;
55 	efi_status s = kBootServices->AllocatePages(AllocateAnyPages,
56 		EfiLoaderData, 1, &addr);
57 
58 	if (s != EFI_SUCCESS)
59 		panic("Unabled to allocate memory: %li", s);
60 
61 	return addr;
62 }
63 
64 
65 extern "C" addr_t
get_next_virtual_address(size_t size)66 get_next_virtual_address(size_t size)
67 {
68 	TRACE("%s: called. size: %" B_PRIuSIZE "\n", __func__, size);
69 
70 	addr_t address = sNextVirtualAddress;
71 	sNextVirtualAddress += ROUNDUP(size, B_PAGE_SIZE);
72 	return address;
73 }
74 
75 
76 extern "C" addr_t
get_current_virtual_address()77 get_current_virtual_address()
78 {
79 	TRACE("%s: called\n", __func__);
80 	return sNextVirtualAddress;
81 }
82 
83 
84 // Platform allocator.
85 // The bootloader assumes that bootloader address space == kernel address space.
86 // This is not true until just before the kernel is booted, so an ugly hack is
87 // used to cover the difference. platform_allocate_region allocates addresses
88 // in bootloader space, but can convert them to kernel space. The ELF loader
89 // accesses kernel memory via Mao(), and much later in the boot process,
90 // addresses in the kernel argument struct are converted from bootloader
91 // addresses to kernel addresses.
92 
93 extern "C" status_t
platform_allocate_region(void ** _address,size_t size,uint8,bool exactAddress)94 platform_allocate_region(void **_address, size_t size, uint8 /* protection */,
95 	bool exactAddress)
96 {
97 	TRACE("%s: called\n", __func__);
98 
99 	efi_physical_addr addr;
100 	size_t pages = ROUNDUP(size, B_PAGE_SIZE) / B_PAGE_SIZE;
101 	efi_status status;
102 
103 	if (exactAddress) {
104 		addr = (efi_physical_addr)(addr_t)*_address;
105 		status = kBootServices->AllocatePages(AllocateAddress,
106 			EfiLoaderData, pages, &addr);
107 	} else {
108 		addr = 0;
109 		status = kBootServices->AllocatePages(AllocateAnyPages,
110 			EfiLoaderData, pages, &addr);
111 	}
112 
113 	if (status != EFI_SUCCESS)
114 		return B_NO_MEMORY;
115 
116 	// Addresses above 512GB not supported.
117 	// Memory map regions above 512GB can be ignored, but if EFI returns pages
118 	// above that there's nothing that can be done to fix it.
119 	if (addr + size > (512ull * 1024 * 1024 * 1024))
120 		panic("Can't currently support more than 512GB of RAM!");
121 
122 	memory_region *region = new(std::nothrow) memory_region {
123 		next: allocated_regions,
124 #ifdef __riscv
125 		// Disables allocation at fixed virtual address
126 		vaddr: 0,
127 #else
128 		vaddr: *_address == NULL ? 0 : (addr_t)*_address,
129 #endif
130 		paddr: (phys_addr_t)addr,
131 		size: size
132 	};
133 
134 	if (region == NULL) {
135 		kBootServices->FreePages(addr, pages);
136 		return B_NO_MEMORY;
137 	}
138 
139 #ifdef TRACE_MMU
140 	//region->dprint("Allocated");
141 #endif
142 	allocated_regions = region;
143 	*_address = (void *)region->paddr;
144 	return B_OK;
145 }
146 
147 
148 extern "C" status_t
platform_allocate_lomem(void ** _address,size_t size)149 platform_allocate_lomem(void **_address, size_t size)
150 {
151 	TRACE("%s: called\n", __func__);
152 
153 	efi_physical_addr addr = KERNEL_LOAD_BASE - B_PAGE_SIZE;
154 	size_t pages = ROUNDUP(size, B_PAGE_SIZE) / B_PAGE_SIZE;
155 	efi_status status = kBootServices->AllocatePages(AllocateMaxAddress,
156 		EfiLoaderData, pages, &addr);
157 	if (status != EFI_SUCCESS)
158 		return B_NO_MEMORY;
159 
160 	memory_region *region = new(std::nothrow) memory_region {
161 		next: allocated_regions,
162 		vaddr: (addr_t)addr,
163 		paddr: (phys_addr_t)addr,
164 		size: size
165 	};
166 
167 	if (region == NULL) {
168 		kBootServices->FreePages(addr, pages);
169 		return B_NO_MEMORY;
170 	}
171 
172 	allocated_regions = region;
173 	*_address = (void *)region->paddr;
174 	return B_OK;
175 }
176 
177 
178 /*!
179 	Neither \a virtualAddress nor \a size need to be aligned, but the function
180 	will map all pages the range intersects with.
181 	If physicalAddress is not page-aligned, the returned virtual address will
182 	have the same "misalignment".
183 */
184 extern "C" addr_t
mmu_map_physical_memory(addr_t physicalAddress,size_t size,uint32 flags)185 mmu_map_physical_memory(addr_t physicalAddress, size_t size, uint32 flags)
186 {
187 	TRACE("%s: called\n", __func__);
188 
189 	addr_t pageOffset = physicalAddress & (B_PAGE_SIZE - 1);
190 
191 	physicalAddress -= pageOffset;
192 	size += pageOffset;
193 
194 	if (insert_physical_allocated_range(physicalAddress,
195 			ROUNDUP(size, B_PAGE_SIZE)) != B_OK)
196 		return B_NO_MEMORY;
197 
198 	return physicalAddress + pageOffset;
199 }
200 
201 
202 static void
convert_physical_ranges()203 convert_physical_ranges()
204 {
205 	TRACE("%s: called\n", __func__);
206 
207 	addr_range *range = gKernelArgs.physical_allocated_range;
208 	uint32 num_ranges = gKernelArgs.num_physical_allocated_ranges;
209 
210 	for (uint32 i = 0; i < num_ranges; ++i) {
211 		// Addresses above 512GB not supported.
212 		// Memory map regions above 512GB can be ignored, but if EFI returns
213 		// pages above that there's nothing that can be done to fix it.
214 		if (range[i].start + range[i].size > (512ull * 1024 * 1024 * 1024))
215 			panic("Can't currently support more than 512GB of RAM!");
216 
217 		memory_region *region = new(std::nothrow) memory_region {
218 			next: allocated_regions,
219 			vaddr: 0,
220 			paddr: (phys_addr_t)range[i].start,
221 			size: (size_t)range[i].size
222 		};
223 
224 		if (!region)
225 			panic("Couldn't add allocated region");
226 
227 		allocated_regions = region;
228 
229 		// Clear out the allocated range
230 		range[i].start = 0;
231 		range[i].size = 0;
232 		gKernelArgs.num_physical_allocated_ranges--;
233 	}
234 }
235 
236 
237 extern "C" status_t
platform_bootloader_address_to_kernel_address(void * address,addr_t * _result)238 platform_bootloader_address_to_kernel_address(void *address, addr_t *_result)
239 {
240 	TRACE("%s: called\n", __func__);
241 
242 	// Convert any physical ranges prior to looking up address
243 	convert_physical_ranges();
244 
245 	// Double cast needed to avoid sign extension issues on 32-bit architecture
246 	phys_addr_t addr = (phys_addr_t)(addr_t)address;
247 
248 	for (memory_region *region = allocated_regions; region;
249 			region = region->next) {
250 		if (region->paddr <= addr && addr < region->paddr + region->size) {
251 			// Lazily allocate virtual memory.
252 			if (region->vaddr == 0) {
253 				region->vaddr = get_next_virtual_address(region->size);
254 			}
255 			*_result = region->vaddr + (addr - region->paddr);
256 			//dprintf("Converted bootloader address %p in region %#lx-%#lx to %#lx\n",
257 			//	address, region->paddr, region->paddr + region->size, *_result);
258 			return B_OK;
259 		}
260 	}
261 
262 	return B_ERROR;
263 }
264 
265 
266 extern "C" status_t
platform_kernel_address_to_bootloader_address(addr_t address,void ** _result)267 platform_kernel_address_to_bootloader_address(addr_t address, void **_result)
268 {
269 	TRACE("%s: called\n", __func__);
270 
271 	for (memory_region *region = allocated_regions; region;
272 			region = region->next) {
273 		if (region->vaddr != 0 && region->vaddr <= address
274 				&& address < region->vaddr + region->size) {
275 			*_result = (void *)(region->paddr + (address - region->vaddr));
276 			//dprintf("Converted kernel address %#lx in region %#lx-%#lx to %p\n",
277 			//	address, region->vaddr, region->vaddr + region->size, *_result);
278 			return B_OK;
279 		}
280 	}
281 
282 	return B_ERROR;
283 }
284 
285 
286 extern "C" status_t
platform_free_region(void * address,size_t size)287 platform_free_region(void *address, size_t size)
288 {
289 	TRACE("%s: called to release region %p (%" B_PRIuSIZE ")\n", __func__,
290 		address, size);
291 
292 	for (memory_region **ref = &allocated_regions; *ref;
293 			ref = &(*ref)->next) {
294 		// Double cast needed to avoid sign extension issues on 32-bit architecture
295 		if ((*ref)->matches((phys_addr_t)(addr_t)address, size)) {
296 			efi_status status;
297 			status = kBootServices->FreePages((efi_physical_addr)(addr_t)address,
298 				ROUNDUP(size, B_PAGE_SIZE) / B_PAGE_SIZE);
299 			ASSERT_ALWAYS(status == EFI_SUCCESS);
300 			memory_region* old = *ref;
301 			//pointer to current allocated_memory_region* now points to next
302 			*ref = (*ref)->next;
303 #ifdef TRACE_MMU
304 			old->dprint("Freeing");
305 #endif
306 			delete old;
307 			return B_OK;
308 		}
309 	}
310 	panic("platform_free_region: Unknown region to free??");
311 	return B_ERROR; // NOT Reached
312 }
313 
314 
315 bool
mmu_next_region(void ** cookie,addr_t * vaddr,phys_addr_t * paddr,size_t * size)316 mmu_next_region(void** cookie, addr_t* vaddr, phys_addr_t* paddr, size_t* size)
317 {
318 	if (*cookie == NULL)
319 		*cookie = allocated_regions;
320 	else
321 		*cookie = ((memory_region*)*cookie)->next;
322 
323 	memory_region* region = (memory_region*)*cookie;
324 	if (region == NULL)
325 		return false;
326 
327 	if (region->vaddr == 0)
328 		region->vaddr = get_next_virtual_address(region->size);
329 
330 	*vaddr = region->vaddr;
331 	*paddr = region->paddr;
332 	*size = region->size;
333 	return true;
334 }
335