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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright IBM Corp. 2006
4 * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
5 */
6
7#include <linux/memblock.h>
8#include <linux/pfn.h>
9#include <linux/mm.h>
10#include <linux/init.h>
11#include <linux/list.h>
12#include <linux/hugetlb.h>
13#include <linux/slab.h>
14#include <asm/cacheflush.h>
15#include <asm/pgalloc.h>
16#include <asm/pgtable.h>
17#include <asm/setup.h>
18#include <asm/tlbflush.h>
19#include <asm/sections.h>
20#include <asm/set_memory.h>
21
22static DEFINE_MUTEX(vmem_mutex);
23
24struct memory_segment {
25 struct list_head list;
26 unsigned long start;
27 unsigned long size;
28};
29
30static LIST_HEAD(mem_segs);
31
32static void __ref *vmem_alloc_pages(unsigned int order)
33{
34 unsigned long size = PAGE_SIZE << order;
35
36 if (slab_is_available())
37 return (void *)__get_free_pages(GFP_KERNEL, order);
38 return (void *) memblock_phys_alloc(size, size);
39}
40
41void *vmem_crst_alloc(unsigned long val)
42{
43 unsigned long *table;
44
45 table = vmem_alloc_pages(CRST_ALLOC_ORDER);
46 if (table)
47 crst_table_init(table, val);
48 return table;
49}
50
51pte_t __ref *vmem_pte_alloc(void)
52{
53 unsigned long size = PTRS_PER_PTE * sizeof(pte_t);
54 pte_t *pte;
55
56 if (slab_is_available())
57 pte = (pte_t *) page_table_alloc(&init_mm);
58 else
59 pte = (pte_t *) memblock_phys_alloc(size, size);
60 if (!pte)
61 return NULL;
62 memset64((u64 *)pte, _PAGE_INVALID, PTRS_PER_PTE);
63 return pte;
64}
65
66/*
67 * Add a physical memory range to the 1:1 mapping.
68 */
69static int vmem_add_mem(unsigned long start, unsigned long size)
70{
71 unsigned long pgt_prot, sgt_prot, r3_prot;
72 unsigned long pages4k, pages1m, pages2g;
73 unsigned long end = start + size;
74 unsigned long address = start;
75 pgd_t *pg_dir;
76 p4d_t *p4_dir;
77 pud_t *pu_dir;
78 pmd_t *pm_dir;
79 pte_t *pt_dir;
80 int ret = -ENOMEM;
81
82 pgt_prot = pgprot_val(PAGE_KERNEL);
83 sgt_prot = pgprot_val(SEGMENT_KERNEL);
84 r3_prot = pgprot_val(REGION3_KERNEL);
85 if (!MACHINE_HAS_NX) {
86 pgt_prot &= ~_PAGE_NOEXEC;
87 sgt_prot &= ~_SEGMENT_ENTRY_NOEXEC;
88 r3_prot &= ~_REGION_ENTRY_NOEXEC;
89 }
90 pages4k = pages1m = pages2g = 0;
91 while (address < end) {
92 pg_dir = pgd_offset_k(address);
93 if (pgd_none(*pg_dir)) {
94 p4_dir = vmem_crst_alloc(_REGION2_ENTRY_EMPTY);
95 if (!p4_dir)
96 goto out;
97 pgd_populate(&init_mm, pg_dir, p4_dir);
98 }
99 p4_dir = p4d_offset(pg_dir, address);
100 if (p4d_none(*p4_dir)) {
101 pu_dir = vmem_crst_alloc(_REGION3_ENTRY_EMPTY);
102 if (!pu_dir)
103 goto out;
104 p4d_populate(&init_mm, p4_dir, pu_dir);
105 }
106 pu_dir = pud_offset(p4_dir, address);
107 if (MACHINE_HAS_EDAT2 && pud_none(*pu_dir) && address &&
108 !(address & ~PUD_MASK) && (address + PUD_SIZE <= end) &&
109 !debug_pagealloc_enabled()) {
110 pud_val(*pu_dir) = address | r3_prot;
111 address += PUD_SIZE;
112 pages2g++;
113 continue;
114 }
115 if (pud_none(*pu_dir)) {
116 pm_dir = vmem_crst_alloc(_SEGMENT_ENTRY_EMPTY);
117 if (!pm_dir)
118 goto out;
119 pud_populate(&init_mm, pu_dir, pm_dir);
120 }
121 pm_dir = pmd_offset(pu_dir, address);
122 if (MACHINE_HAS_EDAT1 && pmd_none(*pm_dir) && address &&
123 !(address & ~PMD_MASK) && (address + PMD_SIZE <= end) &&
124 !debug_pagealloc_enabled()) {
125 pmd_val(*pm_dir) = address | sgt_prot;
126 address += PMD_SIZE;
127 pages1m++;
128 continue;
129 }
130 if (pmd_none(*pm_dir)) {
131 pt_dir = vmem_pte_alloc();
132 if (!pt_dir)
133 goto out;
134 pmd_populate(&init_mm, pm_dir, pt_dir);
135 }
136
137 pt_dir = pte_offset_kernel(pm_dir, address);
138 pte_val(*pt_dir) = address | pgt_prot;
139 address += PAGE_SIZE;
140 pages4k++;
141 }
142 ret = 0;
143out:
144 update_page_count(PG_DIRECT_MAP_4K, pages4k);
145 update_page_count(PG_DIRECT_MAP_1M, pages1m);
146 update_page_count(PG_DIRECT_MAP_2G, pages2g);
147 return ret;
148}
149
150/*
151 * Remove a physical memory range from the 1:1 mapping.
152 * Currently only invalidates page table entries.
153 */
154static void vmem_remove_range(unsigned long start, unsigned long size)
155{
156 unsigned long pages4k, pages1m, pages2g;
157 unsigned long end = start + size;
158 unsigned long address = start;
159 pgd_t *pg_dir;
160 p4d_t *p4_dir;
161 pud_t *pu_dir;
162 pmd_t *pm_dir;
163 pte_t *pt_dir;
164
165 pages4k = pages1m = pages2g = 0;
166 while (address < end) {
167 pg_dir = pgd_offset_k(address);
168 if (pgd_none(*pg_dir)) {
169 address += PGDIR_SIZE;
170 continue;
171 }
172 p4_dir = p4d_offset(pg_dir, address);
173 if (p4d_none(*p4_dir)) {
174 address += P4D_SIZE;
175 continue;
176 }
177 pu_dir = pud_offset(p4_dir, address);
178 if (pud_none(*pu_dir)) {
179 address += PUD_SIZE;
180 continue;
181 }
182 if (pud_large(*pu_dir)) {
183 pud_clear(pu_dir);
184 address += PUD_SIZE;
185 pages2g++;
186 continue;
187 }
188 pm_dir = pmd_offset(pu_dir, address);
189 if (pmd_none(*pm_dir)) {
190 address += PMD_SIZE;
191 continue;
192 }
193 if (pmd_large(*pm_dir)) {
194 pmd_clear(pm_dir);
195 address += PMD_SIZE;
196 pages1m++;
197 continue;
198 }
199 pt_dir = pte_offset_kernel(pm_dir, address);
200 pte_clear(&init_mm, address, pt_dir);
201 address += PAGE_SIZE;
202 pages4k++;
203 }
204 flush_tlb_kernel_range(start, end);
205 update_page_count(PG_DIRECT_MAP_4K, -pages4k);
206 update_page_count(PG_DIRECT_MAP_1M, -pages1m);
207 update_page_count(PG_DIRECT_MAP_2G, -pages2g);
208}
209
210/*
211 * Add a backed mem_map array to the virtual mem_map array.
212 */
213int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
214 struct vmem_altmap *altmap)
215{
216 unsigned long pgt_prot, sgt_prot;
217 unsigned long address = start;
218 pgd_t *pg_dir;
219 p4d_t *p4_dir;
220 pud_t *pu_dir;
221 pmd_t *pm_dir;
222 pte_t *pt_dir;
223 int ret = -ENOMEM;
224
225 pgt_prot = pgprot_val(PAGE_KERNEL);
226 sgt_prot = pgprot_val(SEGMENT_KERNEL);
227 if (!MACHINE_HAS_NX) {
228 pgt_prot &= ~_PAGE_NOEXEC;
229 sgt_prot &= ~_SEGMENT_ENTRY_NOEXEC;
230 }
231 for (address = start; address < end;) {
232 pg_dir = pgd_offset_k(address);
233 if (pgd_none(*pg_dir)) {
234 p4_dir = vmem_crst_alloc(_REGION2_ENTRY_EMPTY);
235 if (!p4_dir)
236 goto out;
237 pgd_populate(&init_mm, pg_dir, p4_dir);
238 }
239
240 p4_dir = p4d_offset(pg_dir, address);
241 if (p4d_none(*p4_dir)) {
242 pu_dir = vmem_crst_alloc(_REGION3_ENTRY_EMPTY);
243 if (!pu_dir)
244 goto out;
245 p4d_populate(&init_mm, p4_dir, pu_dir);
246 }
247
248 pu_dir = pud_offset(p4_dir, address);
249 if (pud_none(*pu_dir)) {
250 pm_dir = vmem_crst_alloc(_SEGMENT_ENTRY_EMPTY);
251 if (!pm_dir)
252 goto out;
253 pud_populate(&init_mm, pu_dir, pm_dir);
254 }
255
256 pm_dir = pmd_offset(pu_dir, address);
257 if (pmd_none(*pm_dir)) {
258 /* Use 1MB frames for vmemmap if available. We always
259 * use large frames even if they are only partially
260 * used.
261 * Otherwise we would have also page tables since
262 * vmemmap_populate gets called for each section
263 * separately. */
264 if (MACHINE_HAS_EDAT1) {
265 void *new_page;
266
267 new_page = vmemmap_alloc_block(PMD_SIZE, node);
268 if (!new_page)
269 goto out;
270 pmd_val(*pm_dir) = __pa(new_page) | sgt_prot;
271 address = (address + PMD_SIZE) & PMD_MASK;
272 continue;
273 }
274 pt_dir = vmem_pte_alloc();
275 if (!pt_dir)
276 goto out;
277 pmd_populate(&init_mm, pm_dir, pt_dir);
278 } else if (pmd_large(*pm_dir)) {
279 address = (address + PMD_SIZE) & PMD_MASK;
280 continue;
281 }
282
283 pt_dir = pte_offset_kernel(pm_dir, address);
284 if (pte_none(*pt_dir)) {
285 void *new_page;
286
287 new_page = vmemmap_alloc_block(PAGE_SIZE, node);
288 if (!new_page)
289 goto out;
290 pte_val(*pt_dir) = __pa(new_page) | pgt_prot;
291 }
292 address += PAGE_SIZE;
293 }
294 ret = 0;
295out:
296 return ret;
297}
298
299void vmemmap_free(unsigned long start, unsigned long end,
300 struct vmem_altmap *altmap)
301{
302}
303
304/*
305 * Add memory segment to the segment list if it doesn't overlap with
306 * an already present segment.
307 */
308static int insert_memory_segment(struct memory_segment *seg)
309{
310 struct memory_segment *tmp;
311
312 if (seg->start + seg->size > VMEM_MAX_PHYS ||
313 seg->start + seg->size < seg->start)
314 return -ERANGE;
315
316 list_for_each_entry(tmp, &mem_segs, list) {
317 if (seg->start >= tmp->start + tmp->size)
318 continue;
319 if (seg->start + seg->size <= tmp->start)
320 continue;
321 return -ENOSPC;
322 }
323 list_add(&seg->list, &mem_segs);
324 return 0;
325}
326
327/*
328 * Remove memory segment from the segment list.
329 */
330static void remove_memory_segment(struct memory_segment *seg)
331{
332 list_del(&seg->list);
333}
334
335static void __remove_shared_memory(struct memory_segment *seg)
336{
337 remove_memory_segment(seg);
338 vmem_remove_range(seg->start, seg->size);
339}
340
341int vmem_remove_mapping(unsigned long start, unsigned long size)
342{
343 struct memory_segment *seg;
344 int ret;
345
346 mutex_lock(&vmem_mutex);
347
348 ret = -ENOENT;
349 list_for_each_entry(seg, &mem_segs, list) {
350 if (seg->start == start && seg->size == size)
351 break;
352 }
353
354 if (seg->start != start || seg->size != size)
355 goto out;
356
357 ret = 0;
358 __remove_shared_memory(seg);
359 kfree(seg);
360out:
361 mutex_unlock(&vmem_mutex);
362 return ret;
363}
364
365int vmem_add_mapping(unsigned long start, unsigned long size)
366{
367 struct memory_segment *seg;
368 int ret;
369
370 mutex_lock(&vmem_mutex);
371 ret = -ENOMEM;
372 seg = kzalloc(sizeof(*seg), GFP_KERNEL);
373 if (!seg)
374 goto out;
375 seg->start = start;
376 seg->size = size;
377
378 ret = insert_memory_segment(seg);
379 if (ret)
380 goto out_free;
381
382 ret = vmem_add_mem(start, size);
383 if (ret)
384 goto out_remove;
385 goto out;
386
387out_remove:
388 __remove_shared_memory(seg);
389out_free:
390 kfree(seg);
391out:
392 mutex_unlock(&vmem_mutex);
393 return ret;
394}
395
396/*
397 * map whole physical memory to virtual memory (identity mapping)
398 * we reserve enough space in the vmalloc area for vmemmap to hotplug
399 * additional memory segments.
400 */
401void __init vmem_map_init(void)
402{
403 struct memblock_region *reg;
404
405 for_each_memblock(memory, reg)
406 vmem_add_mem(reg->base, reg->size);
407 __set_memory((unsigned long)_stext,
408 (unsigned long)(_etext - _stext) >> PAGE_SHIFT,
409 SET_MEMORY_RO | SET_MEMORY_X);
410 __set_memory((unsigned long)_etext,
411 (unsigned long)(__end_rodata - _etext) >> PAGE_SHIFT,
412 SET_MEMORY_RO);
413 __set_memory((unsigned long)_sinittext,
414 (unsigned long)(_einittext - _sinittext) >> PAGE_SHIFT,
415 SET_MEMORY_RO | SET_MEMORY_X);
416 __set_memory(__stext_dma, (__etext_dma - __stext_dma) >> PAGE_SHIFT,
417 SET_MEMORY_RO | SET_MEMORY_X);
418 pr_info("Write protected kernel read-only data: %luk\n",
419 (unsigned long)(__end_rodata - _stext) >> 10);
420}
421
422/*
423 * Convert memblock.memory to a memory segment list so there is a single
424 * list that contains all memory segments.
425 */
426static int __init vmem_convert_memory_chunk(void)
427{
428 struct memblock_region *reg;
429 struct memory_segment *seg;
430
431 mutex_lock(&vmem_mutex);
432 for_each_memblock(memory, reg) {
433 seg = kzalloc(sizeof(*seg), GFP_KERNEL);
434 if (!seg)
435 panic("Out of memory...\n");
436 seg->start = reg->base;
437 seg->size = reg->size;
438 insert_memory_segment(seg);
439 }
440 mutex_unlock(&vmem_mutex);
441 return 0;
442}
443
444core_initcall(vmem_convert_memory_chunk);
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright IBM Corp. 2006
4 * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
5 */
6
7#include <linux/bootmem.h>
8#include <linux/pfn.h>
9#include <linux/mm.h>
10#include <linux/init.h>
11#include <linux/list.h>
12#include <linux/hugetlb.h>
13#include <linux/slab.h>
14#include <linux/memblock.h>
15#include <asm/cacheflush.h>
16#include <asm/pgalloc.h>
17#include <asm/pgtable.h>
18#include <asm/setup.h>
19#include <asm/tlbflush.h>
20#include <asm/sections.h>
21#include <asm/set_memory.h>
22
23static DEFINE_MUTEX(vmem_mutex);
24
25struct memory_segment {
26 struct list_head list;
27 unsigned long start;
28 unsigned long size;
29};
30
31static LIST_HEAD(mem_segs);
32
33static void __ref *vmem_alloc_pages(unsigned int order)
34{
35 unsigned long size = PAGE_SIZE << order;
36
37 if (slab_is_available())
38 return (void *)__get_free_pages(GFP_KERNEL, order);
39 return (void *) memblock_alloc(size, size);
40}
41
42void *vmem_crst_alloc(unsigned long val)
43{
44 unsigned long *table;
45
46 table = vmem_alloc_pages(CRST_ALLOC_ORDER);
47 if (table)
48 crst_table_init(table, val);
49 return table;
50}
51
52pte_t __ref *vmem_pte_alloc(void)
53{
54 unsigned long size = PTRS_PER_PTE * sizeof(pte_t);
55 pte_t *pte;
56
57 if (slab_is_available())
58 pte = (pte_t *) page_table_alloc(&init_mm);
59 else
60 pte = (pte_t *) memblock_alloc(size, size);
61 if (!pte)
62 return NULL;
63 memset64((u64 *)pte, _PAGE_INVALID, PTRS_PER_PTE);
64 return pte;
65}
66
67/*
68 * Add a physical memory range to the 1:1 mapping.
69 */
70static int vmem_add_mem(unsigned long start, unsigned long size)
71{
72 unsigned long pgt_prot, sgt_prot, r3_prot;
73 unsigned long pages4k, pages1m, pages2g;
74 unsigned long end = start + size;
75 unsigned long address = start;
76 pgd_t *pg_dir;
77 p4d_t *p4_dir;
78 pud_t *pu_dir;
79 pmd_t *pm_dir;
80 pte_t *pt_dir;
81 int ret = -ENOMEM;
82
83 pgt_prot = pgprot_val(PAGE_KERNEL);
84 sgt_prot = pgprot_val(SEGMENT_KERNEL);
85 r3_prot = pgprot_val(REGION3_KERNEL);
86 if (!MACHINE_HAS_NX) {
87 pgt_prot &= ~_PAGE_NOEXEC;
88 sgt_prot &= ~_SEGMENT_ENTRY_NOEXEC;
89 r3_prot &= ~_REGION_ENTRY_NOEXEC;
90 }
91 pages4k = pages1m = pages2g = 0;
92 while (address < end) {
93 pg_dir = pgd_offset_k(address);
94 if (pgd_none(*pg_dir)) {
95 p4_dir = vmem_crst_alloc(_REGION2_ENTRY_EMPTY);
96 if (!p4_dir)
97 goto out;
98 pgd_populate(&init_mm, pg_dir, p4_dir);
99 }
100 p4_dir = p4d_offset(pg_dir, address);
101 if (p4d_none(*p4_dir)) {
102 pu_dir = vmem_crst_alloc(_REGION3_ENTRY_EMPTY);
103 if (!pu_dir)
104 goto out;
105 p4d_populate(&init_mm, p4_dir, pu_dir);
106 }
107 pu_dir = pud_offset(p4_dir, address);
108 if (MACHINE_HAS_EDAT2 && pud_none(*pu_dir) && address &&
109 !(address & ~PUD_MASK) && (address + PUD_SIZE <= end) &&
110 !debug_pagealloc_enabled()) {
111 pud_val(*pu_dir) = address | r3_prot;
112 address += PUD_SIZE;
113 pages2g++;
114 continue;
115 }
116 if (pud_none(*pu_dir)) {
117 pm_dir = vmem_crst_alloc(_SEGMENT_ENTRY_EMPTY);
118 if (!pm_dir)
119 goto out;
120 pud_populate(&init_mm, pu_dir, pm_dir);
121 }
122 pm_dir = pmd_offset(pu_dir, address);
123 if (MACHINE_HAS_EDAT1 && pmd_none(*pm_dir) && address &&
124 !(address & ~PMD_MASK) && (address + PMD_SIZE <= end) &&
125 !debug_pagealloc_enabled()) {
126 pmd_val(*pm_dir) = address | sgt_prot;
127 address += PMD_SIZE;
128 pages1m++;
129 continue;
130 }
131 if (pmd_none(*pm_dir)) {
132 pt_dir = vmem_pte_alloc();
133 if (!pt_dir)
134 goto out;
135 pmd_populate(&init_mm, pm_dir, pt_dir);
136 }
137
138 pt_dir = pte_offset_kernel(pm_dir, address);
139 pte_val(*pt_dir) = address | pgt_prot;
140 address += PAGE_SIZE;
141 pages4k++;
142 }
143 ret = 0;
144out:
145 update_page_count(PG_DIRECT_MAP_4K, pages4k);
146 update_page_count(PG_DIRECT_MAP_1M, pages1m);
147 update_page_count(PG_DIRECT_MAP_2G, pages2g);
148 return ret;
149}
150
151/*
152 * Remove a physical memory range from the 1:1 mapping.
153 * Currently only invalidates page table entries.
154 */
155static void vmem_remove_range(unsigned long start, unsigned long size)
156{
157 unsigned long pages4k, pages1m, pages2g;
158 unsigned long end = start + size;
159 unsigned long address = start;
160 pgd_t *pg_dir;
161 p4d_t *p4_dir;
162 pud_t *pu_dir;
163 pmd_t *pm_dir;
164 pte_t *pt_dir;
165
166 pages4k = pages1m = pages2g = 0;
167 while (address < end) {
168 pg_dir = pgd_offset_k(address);
169 if (pgd_none(*pg_dir)) {
170 address += PGDIR_SIZE;
171 continue;
172 }
173 p4_dir = p4d_offset(pg_dir, address);
174 if (p4d_none(*p4_dir)) {
175 address += P4D_SIZE;
176 continue;
177 }
178 pu_dir = pud_offset(p4_dir, address);
179 if (pud_none(*pu_dir)) {
180 address += PUD_SIZE;
181 continue;
182 }
183 if (pud_large(*pu_dir)) {
184 pud_clear(pu_dir);
185 address += PUD_SIZE;
186 pages2g++;
187 continue;
188 }
189 pm_dir = pmd_offset(pu_dir, address);
190 if (pmd_none(*pm_dir)) {
191 address += PMD_SIZE;
192 continue;
193 }
194 if (pmd_large(*pm_dir)) {
195 pmd_clear(pm_dir);
196 address += PMD_SIZE;
197 pages1m++;
198 continue;
199 }
200 pt_dir = pte_offset_kernel(pm_dir, address);
201 pte_clear(&init_mm, address, pt_dir);
202 address += PAGE_SIZE;
203 pages4k++;
204 }
205 flush_tlb_kernel_range(start, end);
206 update_page_count(PG_DIRECT_MAP_4K, -pages4k);
207 update_page_count(PG_DIRECT_MAP_1M, -pages1m);
208 update_page_count(PG_DIRECT_MAP_2G, -pages2g);
209}
210
211/*
212 * Add a backed mem_map array to the virtual mem_map array.
213 */
214int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
215 struct vmem_altmap *altmap)
216{
217 unsigned long pgt_prot, sgt_prot;
218 unsigned long address = start;
219 pgd_t *pg_dir;
220 p4d_t *p4_dir;
221 pud_t *pu_dir;
222 pmd_t *pm_dir;
223 pte_t *pt_dir;
224 int ret = -ENOMEM;
225
226 pgt_prot = pgprot_val(PAGE_KERNEL);
227 sgt_prot = pgprot_val(SEGMENT_KERNEL);
228 if (!MACHINE_HAS_NX) {
229 pgt_prot &= ~_PAGE_NOEXEC;
230 sgt_prot &= ~_SEGMENT_ENTRY_NOEXEC;
231 }
232 for (address = start; address < end;) {
233 pg_dir = pgd_offset_k(address);
234 if (pgd_none(*pg_dir)) {
235 p4_dir = vmem_crst_alloc(_REGION2_ENTRY_EMPTY);
236 if (!p4_dir)
237 goto out;
238 pgd_populate(&init_mm, pg_dir, p4_dir);
239 }
240
241 p4_dir = p4d_offset(pg_dir, address);
242 if (p4d_none(*p4_dir)) {
243 pu_dir = vmem_crst_alloc(_REGION3_ENTRY_EMPTY);
244 if (!pu_dir)
245 goto out;
246 p4d_populate(&init_mm, p4_dir, pu_dir);
247 }
248
249 pu_dir = pud_offset(p4_dir, address);
250 if (pud_none(*pu_dir)) {
251 pm_dir = vmem_crst_alloc(_SEGMENT_ENTRY_EMPTY);
252 if (!pm_dir)
253 goto out;
254 pud_populate(&init_mm, pu_dir, pm_dir);
255 }
256
257 pm_dir = pmd_offset(pu_dir, address);
258 if (pmd_none(*pm_dir)) {
259 /* Use 1MB frames for vmemmap if available. We always
260 * use large frames even if they are only partially
261 * used.
262 * Otherwise we would have also page tables since
263 * vmemmap_populate gets called for each section
264 * separately. */
265 if (MACHINE_HAS_EDAT1) {
266 void *new_page;
267
268 new_page = vmemmap_alloc_block(PMD_SIZE, node);
269 if (!new_page)
270 goto out;
271 pmd_val(*pm_dir) = __pa(new_page) | sgt_prot;
272 address = (address + PMD_SIZE) & PMD_MASK;
273 continue;
274 }
275 pt_dir = vmem_pte_alloc();
276 if (!pt_dir)
277 goto out;
278 pmd_populate(&init_mm, pm_dir, pt_dir);
279 } else if (pmd_large(*pm_dir)) {
280 address = (address + PMD_SIZE) & PMD_MASK;
281 continue;
282 }
283
284 pt_dir = pte_offset_kernel(pm_dir, address);
285 if (pte_none(*pt_dir)) {
286 void *new_page;
287
288 new_page = vmemmap_alloc_block(PAGE_SIZE, node);
289 if (!new_page)
290 goto out;
291 pte_val(*pt_dir) = __pa(new_page) | pgt_prot;
292 }
293 address += PAGE_SIZE;
294 }
295 ret = 0;
296out:
297 return ret;
298}
299
300void vmemmap_free(unsigned long start, unsigned long end,
301 struct vmem_altmap *altmap)
302{
303}
304
305/*
306 * Add memory segment to the segment list if it doesn't overlap with
307 * an already present segment.
308 */
309static int insert_memory_segment(struct memory_segment *seg)
310{
311 struct memory_segment *tmp;
312
313 if (seg->start + seg->size > VMEM_MAX_PHYS ||
314 seg->start + seg->size < seg->start)
315 return -ERANGE;
316
317 list_for_each_entry(tmp, &mem_segs, list) {
318 if (seg->start >= tmp->start + tmp->size)
319 continue;
320 if (seg->start + seg->size <= tmp->start)
321 continue;
322 return -ENOSPC;
323 }
324 list_add(&seg->list, &mem_segs);
325 return 0;
326}
327
328/*
329 * Remove memory segment from the segment list.
330 */
331static void remove_memory_segment(struct memory_segment *seg)
332{
333 list_del(&seg->list);
334}
335
336static void __remove_shared_memory(struct memory_segment *seg)
337{
338 remove_memory_segment(seg);
339 vmem_remove_range(seg->start, seg->size);
340}
341
342int vmem_remove_mapping(unsigned long start, unsigned long size)
343{
344 struct memory_segment *seg;
345 int ret;
346
347 mutex_lock(&vmem_mutex);
348
349 ret = -ENOENT;
350 list_for_each_entry(seg, &mem_segs, list) {
351 if (seg->start == start && seg->size == size)
352 break;
353 }
354
355 if (seg->start != start || seg->size != size)
356 goto out;
357
358 ret = 0;
359 __remove_shared_memory(seg);
360 kfree(seg);
361out:
362 mutex_unlock(&vmem_mutex);
363 return ret;
364}
365
366int vmem_add_mapping(unsigned long start, unsigned long size)
367{
368 struct memory_segment *seg;
369 int ret;
370
371 mutex_lock(&vmem_mutex);
372 ret = -ENOMEM;
373 seg = kzalloc(sizeof(*seg), GFP_KERNEL);
374 if (!seg)
375 goto out;
376 seg->start = start;
377 seg->size = size;
378
379 ret = insert_memory_segment(seg);
380 if (ret)
381 goto out_free;
382
383 ret = vmem_add_mem(start, size);
384 if (ret)
385 goto out_remove;
386 goto out;
387
388out_remove:
389 __remove_shared_memory(seg);
390out_free:
391 kfree(seg);
392out:
393 mutex_unlock(&vmem_mutex);
394 return ret;
395}
396
397/*
398 * map whole physical memory to virtual memory (identity mapping)
399 * we reserve enough space in the vmalloc area for vmemmap to hotplug
400 * additional memory segments.
401 */
402void __init vmem_map_init(void)
403{
404 struct memblock_region *reg;
405
406 for_each_memblock(memory, reg)
407 vmem_add_mem(reg->base, reg->size);
408 __set_memory((unsigned long)_stext,
409 (unsigned long)(_etext - _stext) >> PAGE_SHIFT,
410 SET_MEMORY_RO | SET_MEMORY_X);
411 __set_memory((unsigned long)_etext,
412 (unsigned long)(__end_rodata - _etext) >> PAGE_SHIFT,
413 SET_MEMORY_RO);
414 __set_memory((unsigned long)_sinittext,
415 (unsigned long)(_einittext - _sinittext) >> PAGE_SHIFT,
416 SET_MEMORY_RO | SET_MEMORY_X);
417 pr_info("Write protected kernel read-only data: %luk\n",
418 (unsigned long)(__end_rodata - _stext) >> 10);
419}
420
421/*
422 * Convert memblock.memory to a memory segment list so there is a single
423 * list that contains all memory segments.
424 */
425static int __init vmem_convert_memory_chunk(void)
426{
427 struct memblock_region *reg;
428 struct memory_segment *seg;
429
430 mutex_lock(&vmem_mutex);
431 for_each_memblock(memory, reg) {
432 seg = kzalloc(sizeof(*seg), GFP_KERNEL);
433 if (!seg)
434 panic("Out of memory...\n");
435 seg->start = reg->base;
436 seg->size = reg->size;
437 insert_memory_segment(seg);
438 }
439 mutex_unlock(&vmem_mutex);
440 return 0;
441}
442
443core_initcall(vmem_convert_memory_chunk);