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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * PowerPC version
4 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
5 *
6 * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
7 * and Cort Dougan (PReP) (cort@cs.nmt.edu)
8 * Copyright (C) 1996 Paul Mackerras
9 * PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
10 *
11 * Derived from "arch/i386/mm/init.c"
12 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
13 */
14
15#include <linux/memblock.h>
16#include <linux/highmem.h>
17#include <linux/suspend.h>
18#include <linux/dma-direct.h>
19
20#include <asm/swiotlb.h>
21#include <asm/machdep.h>
22#include <asm/rtas.h>
23#include <asm/kasan.h>
24#include <asm/svm.h>
25#include <asm/mmzone.h>
26#include <asm/ftrace.h>
27#include <asm/code-patching.h>
28#include <asm/setup.h>
29#include <asm/fixmap.h>
30
31#include <mm/mmu_decl.h>
32
33unsigned long long memory_limit;
34
35unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
36EXPORT_SYMBOL(empty_zero_page);
37
38pgprot_t __phys_mem_access_prot(unsigned long pfn, unsigned long size,
39 pgprot_t vma_prot)
40{
41 if (ppc_md.phys_mem_access_prot)
42 return ppc_md.phys_mem_access_prot(pfn, size, vma_prot);
43
44 if (!page_is_ram(pfn))
45 vma_prot = pgprot_noncached(vma_prot);
46
47 return vma_prot;
48}
49EXPORT_SYMBOL(__phys_mem_access_prot);
50
51#ifdef CONFIG_MEMORY_HOTPLUG
52static DEFINE_MUTEX(linear_mapping_mutex);
53
54#ifdef CONFIG_NUMA
55int memory_add_physaddr_to_nid(u64 start)
56{
57 return hot_add_scn_to_nid(start);
58}
59EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
60#endif
61
62int __weak create_section_mapping(unsigned long start, unsigned long end,
63 int nid, pgprot_t prot)
64{
65 return -ENODEV;
66}
67
68int __weak remove_section_mapping(unsigned long start, unsigned long end)
69{
70 return -ENODEV;
71}
72
73int __ref arch_create_linear_mapping(int nid, u64 start, u64 size,
74 struct mhp_params *params)
75{
76 int rc;
77
78 start = (unsigned long)__va(start);
79 mutex_lock(&linear_mapping_mutex);
80 rc = create_section_mapping(start, start + size, nid,
81 params->pgprot);
82 mutex_unlock(&linear_mapping_mutex);
83 if (rc) {
84 pr_warn("Unable to create linear mapping for 0x%llx..0x%llx: %d\n",
85 start, start + size, rc);
86 return -EFAULT;
87 }
88 return 0;
89}
90
91void __ref arch_remove_linear_mapping(u64 start, u64 size)
92{
93 int ret;
94
95 /* Remove htab bolted mappings for this section of memory */
96 start = (unsigned long)__va(start);
97
98 mutex_lock(&linear_mapping_mutex);
99 ret = remove_section_mapping(start, start + size);
100 mutex_unlock(&linear_mapping_mutex);
101 if (ret)
102 pr_warn("Unable to remove linear mapping for 0x%llx..0x%llx: %d\n",
103 start, start + size, ret);
104
105 /* Ensure all vmalloc mappings are flushed in case they also
106 * hit that section of memory
107 */
108 vm_unmap_aliases();
109}
110
111/*
112 * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
113 * updating.
114 */
115static void update_end_of_memory_vars(u64 start, u64 size)
116{
117 unsigned long end_pfn = PFN_UP(start + size);
118
119 if (end_pfn > max_pfn) {
120 max_pfn = end_pfn;
121 max_low_pfn = end_pfn;
122 high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
123 }
124}
125
126int __ref add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
127 struct mhp_params *params)
128{
129 int ret;
130
131 ret = __add_pages(nid, start_pfn, nr_pages, params);
132 if (ret)
133 return ret;
134
135 /* update max_pfn, max_low_pfn and high_memory */
136 update_end_of_memory_vars(start_pfn << PAGE_SHIFT,
137 nr_pages << PAGE_SHIFT);
138
139 return ret;
140}
141
142int __ref arch_add_memory(int nid, u64 start, u64 size,
143 struct mhp_params *params)
144{
145 unsigned long start_pfn = start >> PAGE_SHIFT;
146 unsigned long nr_pages = size >> PAGE_SHIFT;
147 int rc;
148
149 rc = arch_create_linear_mapping(nid, start, size, params);
150 if (rc)
151 return rc;
152 rc = add_pages(nid, start_pfn, nr_pages, params);
153 if (rc)
154 arch_remove_linear_mapping(start, size);
155 return rc;
156}
157
158void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
159{
160 unsigned long start_pfn = start >> PAGE_SHIFT;
161 unsigned long nr_pages = size >> PAGE_SHIFT;
162
163 __remove_pages(start_pfn, nr_pages, altmap);
164 arch_remove_linear_mapping(start, size);
165}
166#endif
167
168#ifndef CONFIG_NUMA
169void __init mem_topology_setup(void)
170{
171 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
172 min_low_pfn = MEMORY_START >> PAGE_SHIFT;
173#ifdef CONFIG_HIGHMEM
174 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
175#endif
176
177 /* Place all memblock_regions in the same node and merge contiguous
178 * memblock_regions
179 */
180 memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
181}
182
183void __init initmem_init(void)
184{
185 sparse_init();
186}
187
188/* mark pages that don't exist as nosave */
189static int __init mark_nonram_nosave(void)
190{
191 unsigned long spfn, epfn, prev = 0;
192 int i;
193
194 for_each_mem_pfn_range(i, MAX_NUMNODES, &spfn, &epfn, NULL) {
195 if (prev && prev < spfn)
196 register_nosave_region(prev, spfn);
197
198 prev = epfn;
199 }
200
201 return 0;
202}
203#else /* CONFIG_NUMA */
204static int __init mark_nonram_nosave(void)
205{
206 return 0;
207}
208#endif
209
210/*
211 * Zones usage:
212 *
213 * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be
214 * everything else. GFP_DMA32 page allocations automatically fall back to
215 * ZONE_DMA.
216 *
217 * By using 31-bit unconditionally, we can exploit zone_dma_bits to inform the
218 * generic DMA mapping code. 32-bit only devices (if not handled by an IOMMU
219 * anyway) will take a first dip into ZONE_NORMAL and get otherwise served by
220 * ZONE_DMA.
221 */
222static unsigned long max_zone_pfns[MAX_NR_ZONES];
223
224/*
225 * paging_init() sets up the page tables - in fact we've already done this.
226 */
227void __init paging_init(void)
228{
229 unsigned long long total_ram = memblock_phys_mem_size();
230 phys_addr_t top_of_ram = memblock_end_of_DRAM();
231
232#ifdef CONFIG_HIGHMEM
233 unsigned long v = __fix_to_virt(FIX_KMAP_END);
234 unsigned long end = __fix_to_virt(FIX_KMAP_BEGIN);
235
236 for (; v < end; v += PAGE_SIZE)
237 map_kernel_page(v, 0, __pgprot(0)); /* XXX gross */
238
239 map_kernel_page(PKMAP_BASE, 0, __pgprot(0)); /* XXX gross */
240 pkmap_page_table = virt_to_kpte(PKMAP_BASE);
241#endif /* CONFIG_HIGHMEM */
242
243 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",
244 (unsigned long long)top_of_ram, total_ram);
245 printk(KERN_DEBUG "Memory hole size: %ldMB\n",
246 (long int)((top_of_ram - total_ram) >> 20));
247
248 /*
249 * Allow 30-bit DMA for very limited Broadcom wifi chips on many
250 * powerbooks.
251 */
252 if (IS_ENABLED(CONFIG_PPC32))
253 zone_dma_bits = 30;
254 else
255 zone_dma_bits = 31;
256
257#ifdef CONFIG_ZONE_DMA
258 max_zone_pfns[ZONE_DMA] = min(max_low_pfn,
259 1UL << (zone_dma_bits - PAGE_SHIFT));
260#endif
261 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
262#ifdef CONFIG_HIGHMEM
263 max_zone_pfns[ZONE_HIGHMEM] = max_pfn;
264#endif
265
266 free_area_init(max_zone_pfns);
267
268 mark_nonram_nosave();
269}
270
271void __init mem_init(void)
272{
273 /*
274 * book3s is limited to 16 page sizes due to encoding this in
275 * a 4-bit field for slices.
276 */
277 BUILD_BUG_ON(MMU_PAGE_COUNT > 16);
278
279#ifdef CONFIG_SWIOTLB
280 /*
281 * Some platforms (e.g. 85xx) limit DMA-able memory way below
282 * 4G. We force memblock to bottom-up mode to ensure that the
283 * memory allocated in swiotlb_init() is DMA-able.
284 * As it's the last memblock allocation, no need to reset it
285 * back to to-down.
286 */
287 memblock_set_bottom_up(true);
288 swiotlb_init(ppc_swiotlb_enable, ppc_swiotlb_flags);
289#endif
290
291 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
292
293 kasan_late_init();
294
295 memblock_free_all();
296
297#ifdef CONFIG_HIGHMEM
298 {
299 unsigned long pfn, highmem_mapnr;
300
301 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT;
302 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
303 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT;
304 struct page *page = pfn_to_page(pfn);
305 if (memblock_is_memory(paddr) && !memblock_is_reserved(paddr))
306 free_highmem_page(page);
307 }
308 }
309#endif /* CONFIG_HIGHMEM */
310
311#if defined(CONFIG_PPC_E500) && !defined(CONFIG_SMP)
312 /*
313 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up
314 * functions.... do it here for the non-smp case.
315 */
316 per_cpu(next_tlbcam_idx, smp_processor_id()) =
317 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1;
318#endif
319
320#ifdef CONFIG_PPC32
321 pr_info("Kernel virtual memory layout:\n");
322#ifdef CONFIG_KASAN
323 pr_info(" * 0x%08lx..0x%08lx : kasan shadow mem\n",
324 KASAN_SHADOW_START, KASAN_SHADOW_END);
325#endif
326 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP);
327#ifdef CONFIG_HIGHMEM
328 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n",
329 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
330#endif /* CONFIG_HIGHMEM */
331 if (ioremap_bot != IOREMAP_TOP)
332 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n",
333 ioremap_bot, IOREMAP_TOP);
334 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n",
335 VMALLOC_START, VMALLOC_END);
336#ifdef MODULES_VADDR
337 pr_info(" * 0x%08lx..0x%08lx : modules\n",
338 MODULES_VADDR, MODULES_END);
339#endif
340#endif /* CONFIG_PPC32 */
341}
342
343void free_initmem(void)
344{
345 ppc_md.progress = ppc_printk_progress;
346 mark_initmem_nx();
347 free_initmem_default(POISON_FREE_INITMEM);
348 ftrace_free_init_tramp();
349}
350
351/*
352 * System memory should not be in /proc/iomem but various tools expect it
353 * (eg kdump).
354 */
355static int __init add_system_ram_resources(void)
356{
357 phys_addr_t start, end;
358 u64 i;
359
360 for_each_mem_range(i, &start, &end) {
361 struct resource *res;
362
363 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
364 WARN_ON(!res);
365
366 if (res) {
367 res->name = "System RAM";
368 res->start = start;
369 /*
370 * In memblock, end points to the first byte after
371 * the range while in resourses, end points to the
372 * last byte in the range.
373 */
374 res->end = end - 1;
375 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
376 WARN_ON(request_resource(&iomem_resource, res) < 0);
377 }
378 }
379
380 return 0;
381}
382subsys_initcall(add_system_ram_resources);
383
384#ifdef CONFIG_STRICT_DEVMEM
385/*
386 * devmem_is_allowed(): check to see if /dev/mem access to a certain address
387 * is valid. The argument is a physical page number.
388 *
389 * Access has to be given to non-kernel-ram areas as well, these contain the
390 * PCI mmio resources as well as potential bios/acpi data regions.
391 */
392int devmem_is_allowed(unsigned long pfn)
393{
394 if (page_is_rtas_user_buf(pfn))
395 return 1;
396 if (iomem_is_exclusive(PFN_PHYS(pfn)))
397 return 0;
398 if (!page_is_ram(pfn))
399 return 1;
400 return 0;
401}
402#endif /* CONFIG_STRICT_DEVMEM */
403
404/*
405 * This is defined in kernel/resource.c but only powerpc needs to export it, for
406 * the EHEA driver. Drop this when drivers/net/ethernet/ibm/ehea is removed.
407 */
408EXPORT_SYMBOL_GPL(walk_system_ram_range);
1/*
2 * PowerPC version
3 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
4 *
5 * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
6 * and Cort Dougan (PReP) (cort@cs.nmt.edu)
7 * Copyright (C) 1996 Paul Mackerras
8 * PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
9 *
10 * Derived from "arch/i386/mm/init.c"
11 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
12 *
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version
16 * 2 of the License, or (at your option) any later version.
17 *
18 */
19
20#include <linux/export.h>
21#include <linux/sched.h>
22#include <linux/kernel.h>
23#include <linux/errno.h>
24#include <linux/string.h>
25#include <linux/gfp.h>
26#include <linux/types.h>
27#include <linux/mm.h>
28#include <linux/stddef.h>
29#include <linux/init.h>
30#include <linux/bootmem.h>
31#include <linux/highmem.h>
32#include <linux/initrd.h>
33#include <linux/pagemap.h>
34#include <linux/suspend.h>
35#include <linux/memblock.h>
36#include <linux/hugetlb.h>
37#include <linux/slab.h>
38#include <linux/vmalloc.h>
39#include <linux/memremap.h>
40
41#include <asm/pgalloc.h>
42#include <asm/prom.h>
43#include <asm/io.h>
44#include <asm/mmu_context.h>
45#include <asm/pgtable.h>
46#include <asm/mmu.h>
47#include <asm/smp.h>
48#include <asm/machdep.h>
49#include <asm/btext.h>
50#include <asm/tlb.h>
51#include <asm/sections.h>
52#include <asm/sparsemem.h>
53#include <asm/vdso.h>
54#include <asm/fixmap.h>
55#include <asm/swiotlb.h>
56#include <asm/rtas.h>
57
58#include "mmu_decl.h"
59
60#ifndef CPU_FTR_COHERENT_ICACHE
61#define CPU_FTR_COHERENT_ICACHE 0 /* XXX for now */
62#define CPU_FTR_NOEXECUTE 0
63#endif
64
65unsigned long long memory_limit;
66
67#ifdef CONFIG_HIGHMEM
68pte_t *kmap_pte;
69EXPORT_SYMBOL(kmap_pte);
70pgprot_t kmap_prot;
71EXPORT_SYMBOL(kmap_prot);
72#define TOP_ZONE ZONE_HIGHMEM
73
74static inline pte_t *virt_to_kpte(unsigned long vaddr)
75{
76 return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr),
77 vaddr), vaddr), vaddr);
78}
79#else
80#define TOP_ZONE ZONE_NORMAL
81#endif
82
83int page_is_ram(unsigned long pfn)
84{
85 return memblock_is_memory(__pfn_to_phys(pfn));
86}
87
88pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
89 unsigned long size, pgprot_t vma_prot)
90{
91 if (ppc_md.phys_mem_access_prot)
92 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot);
93
94 if (!page_is_ram(pfn))
95 vma_prot = pgprot_noncached(vma_prot);
96
97 return vma_prot;
98}
99EXPORT_SYMBOL(phys_mem_access_prot);
100
101#ifdef CONFIG_MEMORY_HOTPLUG
102
103#ifdef CONFIG_NUMA
104int memory_add_physaddr_to_nid(u64 start)
105{
106 return hot_add_scn_to_nid(start);
107}
108#endif
109
110int __weak create_section_mapping(unsigned long start, unsigned long end, int nid)
111{
112 return -ENODEV;
113}
114
115int __weak remove_section_mapping(unsigned long start, unsigned long end)
116{
117 return -ENODEV;
118}
119
120int __meminit arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap,
121 bool want_memblock)
122{
123 unsigned long start_pfn = start >> PAGE_SHIFT;
124 unsigned long nr_pages = size >> PAGE_SHIFT;
125 int rc;
126
127 resize_hpt_for_hotplug(memblock_phys_mem_size());
128
129 start = (unsigned long)__va(start);
130 rc = create_section_mapping(start, start + size, nid);
131 if (rc) {
132 pr_warn("Unable to create mapping for hot added memory 0x%llx..0x%llx: %d\n",
133 start, start + size, rc);
134 return -EFAULT;
135 }
136 flush_inval_dcache_range(start, start + size);
137
138 return __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock);
139}
140
141#ifdef CONFIG_MEMORY_HOTREMOVE
142int __meminit arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap)
143{
144 unsigned long start_pfn = start >> PAGE_SHIFT;
145 unsigned long nr_pages = size >> PAGE_SHIFT;
146 struct page *page;
147 int ret;
148
149 /*
150 * If we have an altmap then we need to skip over any reserved PFNs
151 * when querying the zone.
152 */
153 page = pfn_to_page(start_pfn);
154 if (altmap)
155 page += vmem_altmap_offset(altmap);
156
157 ret = __remove_pages(page_zone(page), start_pfn, nr_pages, altmap);
158 if (ret)
159 return ret;
160
161 /* Remove htab bolted mappings for this section of memory */
162 start = (unsigned long)__va(start);
163 flush_inval_dcache_range(start, start + size);
164 ret = remove_section_mapping(start, start + size);
165
166 /* Ensure all vmalloc mappings are flushed in case they also
167 * hit that section of memory
168 */
169 vm_unmap_aliases();
170
171 resize_hpt_for_hotplug(memblock_phys_mem_size());
172
173 return ret;
174}
175#endif
176#endif /* CONFIG_MEMORY_HOTPLUG */
177
178/*
179 * walk_memory_resource() needs to make sure there is no holes in a given
180 * memory range. PPC64 does not maintain the memory layout in /proc/iomem.
181 * Instead it maintains it in memblock.memory structures. Walk through the
182 * memory regions, find holes and callback for contiguous regions.
183 */
184int
185walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
186 void *arg, int (*func)(unsigned long, unsigned long, void *))
187{
188 struct memblock_region *reg;
189 unsigned long end_pfn = start_pfn + nr_pages;
190 unsigned long tstart, tend;
191 int ret = -1;
192
193 for_each_memblock(memory, reg) {
194 tstart = max(start_pfn, memblock_region_memory_base_pfn(reg));
195 tend = min(end_pfn, memblock_region_memory_end_pfn(reg));
196 if (tstart >= tend)
197 continue;
198 ret = (*func)(tstart, tend - tstart, arg);
199 if (ret)
200 break;
201 }
202 return ret;
203}
204EXPORT_SYMBOL_GPL(walk_system_ram_range);
205
206#ifndef CONFIG_NEED_MULTIPLE_NODES
207void __init mem_topology_setup(void)
208{
209 max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
210 min_low_pfn = MEMORY_START >> PAGE_SHIFT;
211#ifdef CONFIG_HIGHMEM
212 max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
213#endif
214
215 /* Place all memblock_regions in the same node and merge contiguous
216 * memblock_regions
217 */
218 memblock_set_node(0, (phys_addr_t)ULLONG_MAX, &memblock.memory, 0);
219}
220
221void __init initmem_init(void)
222{
223 /* XXX need to clip this if using highmem? */
224 sparse_memory_present_with_active_regions(0);
225 sparse_init();
226}
227
228/* mark pages that don't exist as nosave */
229static int __init mark_nonram_nosave(void)
230{
231 struct memblock_region *reg, *prev = NULL;
232
233 for_each_memblock(memory, reg) {
234 if (prev &&
235 memblock_region_memory_end_pfn(prev) < memblock_region_memory_base_pfn(reg))
236 register_nosave_region(memblock_region_memory_end_pfn(prev),
237 memblock_region_memory_base_pfn(reg));
238 prev = reg;
239 }
240 return 0;
241}
242#else /* CONFIG_NEED_MULTIPLE_NODES */
243static int __init mark_nonram_nosave(void)
244{
245 return 0;
246}
247#endif
248
249static bool zone_limits_final;
250
251/*
252 * The memory zones past TOP_ZONE are managed by generic mm code.
253 * These should be set to zero since that's what every other
254 * architecture does.
255 */
256static unsigned long max_zone_pfns[MAX_NR_ZONES] = {
257 [0 ... TOP_ZONE ] = ~0UL,
258 [TOP_ZONE + 1 ... MAX_NR_ZONES - 1] = 0
259};
260
261/*
262 * Restrict the specified zone and all more restrictive zones
263 * to be below the specified pfn. May not be called after
264 * paging_init().
265 */
266void __init limit_zone_pfn(enum zone_type zone, unsigned long pfn_limit)
267{
268 int i;
269
270 if (WARN_ON(zone_limits_final))
271 return;
272
273 for (i = zone; i >= 0; i--) {
274 if (max_zone_pfns[i] > pfn_limit)
275 max_zone_pfns[i] = pfn_limit;
276 }
277}
278
279/*
280 * Find the least restrictive zone that is entirely below the
281 * specified pfn limit. Returns < 0 if no suitable zone is found.
282 *
283 * pfn_limit must be u64 because it can exceed 32 bits even on 32-bit
284 * systems -- the DMA limit can be higher than any possible real pfn.
285 */
286int dma_pfn_limit_to_zone(u64 pfn_limit)
287{
288 int i;
289
290 for (i = TOP_ZONE; i >= 0; i--) {
291 if (max_zone_pfns[i] <= pfn_limit)
292 return i;
293 }
294
295 return -EPERM;
296}
297
298/*
299 * paging_init() sets up the page tables - in fact we've already done this.
300 */
301void __init paging_init(void)
302{
303 unsigned long long total_ram = memblock_phys_mem_size();
304 phys_addr_t top_of_ram = memblock_end_of_DRAM();
305
306#ifdef CONFIG_PPC32
307 unsigned long v = __fix_to_virt(__end_of_fixed_addresses - 1);
308 unsigned long end = __fix_to_virt(FIX_HOLE);
309
310 for (; v < end; v += PAGE_SIZE)
311 map_kernel_page(v, 0, 0); /* XXX gross */
312#endif
313
314#ifdef CONFIG_HIGHMEM
315 map_kernel_page(PKMAP_BASE, 0, 0); /* XXX gross */
316 pkmap_page_table = virt_to_kpte(PKMAP_BASE);
317
318 kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
319 kmap_prot = PAGE_KERNEL;
320#endif /* CONFIG_HIGHMEM */
321
322 printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",
323 (unsigned long long)top_of_ram, total_ram);
324 printk(KERN_DEBUG "Memory hole size: %ldMB\n",
325 (long int)((top_of_ram - total_ram) >> 20));
326
327#ifdef CONFIG_HIGHMEM
328 limit_zone_pfn(ZONE_NORMAL, lowmem_end_addr >> PAGE_SHIFT);
329#endif
330 limit_zone_pfn(TOP_ZONE, top_of_ram >> PAGE_SHIFT);
331 zone_limits_final = true;
332 free_area_init_nodes(max_zone_pfns);
333
334 mark_nonram_nosave();
335}
336
337void __init mem_init(void)
338{
339 /*
340 * book3s is limited to 16 page sizes due to encoding this in
341 * a 4-bit field for slices.
342 */
343 BUILD_BUG_ON(MMU_PAGE_COUNT > 16);
344
345#ifdef CONFIG_SWIOTLB
346 swiotlb_init(0);
347#endif
348
349 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
350 set_max_mapnr(max_pfn);
351 free_all_bootmem();
352
353#ifdef CONFIG_HIGHMEM
354 {
355 unsigned long pfn, highmem_mapnr;
356
357 highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT;
358 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
359 phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT;
360 struct page *page = pfn_to_page(pfn);
361 if (!memblock_is_reserved(paddr))
362 free_highmem_page(page);
363 }
364 }
365#endif /* CONFIG_HIGHMEM */
366
367#if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP)
368 /*
369 * If smp is enabled, next_tlbcam_idx is initialized in the cpu up
370 * functions.... do it here for the non-smp case.
371 */
372 per_cpu(next_tlbcam_idx, smp_processor_id()) =
373 (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1;
374#endif
375
376 mem_init_print_info(NULL);
377#ifdef CONFIG_PPC32
378 pr_info("Kernel virtual memory layout:\n");
379 pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP);
380#ifdef CONFIG_HIGHMEM
381 pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n",
382 PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
383#endif /* CONFIG_HIGHMEM */
384#ifdef CONFIG_NOT_COHERENT_CACHE
385 pr_info(" * 0x%08lx..0x%08lx : consistent mem\n",
386 IOREMAP_TOP, IOREMAP_TOP + CONFIG_CONSISTENT_SIZE);
387#endif /* CONFIG_NOT_COHERENT_CACHE */
388 pr_info(" * 0x%08lx..0x%08lx : early ioremap\n",
389 ioremap_bot, IOREMAP_TOP);
390 pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n",
391 VMALLOC_START, VMALLOC_END);
392#endif /* CONFIG_PPC32 */
393}
394
395void free_initmem(void)
396{
397 ppc_md.progress = ppc_printk_progress;
398 mark_initmem_nx();
399 free_initmem_default(POISON_FREE_INITMEM);
400}
401
402#ifdef CONFIG_BLK_DEV_INITRD
403void __init free_initrd_mem(unsigned long start, unsigned long end)
404{
405 free_reserved_area((void *)start, (void *)end, -1, "initrd");
406}
407#endif
408
409/*
410 * This is called when a page has been modified by the kernel.
411 * It just marks the page as not i-cache clean. We do the i-cache
412 * flush later when the page is given to a user process, if necessary.
413 */
414void flush_dcache_page(struct page *page)
415{
416 if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
417 return;
418 /* avoid an atomic op if possible */
419 if (test_bit(PG_arch_1, &page->flags))
420 clear_bit(PG_arch_1, &page->flags);
421}
422EXPORT_SYMBOL(flush_dcache_page);
423
424void flush_dcache_icache_page(struct page *page)
425{
426#ifdef CONFIG_HUGETLB_PAGE
427 if (PageCompound(page)) {
428 flush_dcache_icache_hugepage(page);
429 return;
430 }
431#endif
432#if defined(CONFIG_PPC_8xx) || defined(CONFIG_PPC64)
433 /* On 8xx there is no need to kmap since highmem is not supported */
434 __flush_dcache_icache(page_address(page));
435#else
436 if (IS_ENABLED(CONFIG_BOOKE) || sizeof(phys_addr_t) > sizeof(void *)) {
437 void *start = kmap_atomic(page);
438 __flush_dcache_icache(start);
439 kunmap_atomic(start);
440 } else {
441 __flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT);
442 }
443#endif
444}
445EXPORT_SYMBOL(flush_dcache_icache_page);
446
447void clear_user_page(void *page, unsigned long vaddr, struct page *pg)
448{
449 clear_page(page);
450
451 /*
452 * We shouldn't have to do this, but some versions of glibc
453 * require it (ld.so assumes zero filled pages are icache clean)
454 * - Anton
455 */
456 flush_dcache_page(pg);
457}
458EXPORT_SYMBOL(clear_user_page);
459
460void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
461 struct page *pg)
462{
463 copy_page(vto, vfrom);
464
465 /*
466 * We should be able to use the following optimisation, however
467 * there are two problems.
468 * Firstly a bug in some versions of binutils meant PLT sections
469 * were not marked executable.
470 * Secondly the first word in the GOT section is blrl, used
471 * to establish the GOT address. Until recently the GOT was
472 * not marked executable.
473 * - Anton
474 */
475#if 0
476 if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0))
477 return;
478#endif
479
480 flush_dcache_page(pg);
481}
482
483void flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
484 unsigned long addr, int len)
485{
486 unsigned long maddr;
487
488 maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK);
489 flush_icache_range(maddr, maddr + len);
490 kunmap(page);
491}
492EXPORT_SYMBOL(flush_icache_user_range);
493
494/*
495 * This is called at the end of handling a user page fault, when the
496 * fault has been handled by updating a PTE in the linux page tables.
497 * We use it to preload an HPTE into the hash table corresponding to
498 * the updated linux PTE.
499 *
500 * This must always be called with the pte lock held.
501 */
502void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
503 pte_t *ptep)
504{
505#ifdef CONFIG_PPC_STD_MMU
506 /*
507 * We don't need to worry about _PAGE_PRESENT here because we are
508 * called with either mm->page_table_lock held or ptl lock held
509 */
510 unsigned long access, trap;
511
512 if (radix_enabled())
513 return;
514
515 /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */
516 if (!pte_young(*ptep) || address >= TASK_SIZE)
517 return;
518
519 /* We try to figure out if we are coming from an instruction
520 * access fault and pass that down to __hash_page so we avoid
521 * double-faulting on execution of fresh text. We have to test
522 * for regs NULL since init will get here first thing at boot
523 *
524 * We also avoid filling the hash if not coming from a fault
525 */
526
527 trap = current->thread.regs ? TRAP(current->thread.regs) : 0UL;
528 switch (trap) {
529 case 0x300:
530 access = 0UL;
531 break;
532 case 0x400:
533 access = _PAGE_EXEC;
534 break;
535 default:
536 return;
537 }
538
539 hash_preload(vma->vm_mm, address, access, trap);
540#endif /* CONFIG_PPC_STD_MMU */
541#if (defined(CONFIG_PPC_BOOK3E_64) || defined(CONFIG_PPC_FSL_BOOK3E)) \
542 && defined(CONFIG_HUGETLB_PAGE)
543 if (is_vm_hugetlb_page(vma))
544 book3e_hugetlb_preload(vma, address, *ptep);
545#endif
546}
547
548/*
549 * System memory should not be in /proc/iomem but various tools expect it
550 * (eg kdump).
551 */
552static int __init add_system_ram_resources(void)
553{
554 struct memblock_region *reg;
555
556 for_each_memblock(memory, reg) {
557 struct resource *res;
558 unsigned long base = reg->base;
559 unsigned long size = reg->size;
560
561 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
562 WARN_ON(!res);
563
564 if (res) {
565 res->name = "System RAM";
566 res->start = base;
567 res->end = base + size - 1;
568 res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
569 WARN_ON(request_resource(&iomem_resource, res) < 0);
570 }
571 }
572
573 return 0;
574}
575subsys_initcall(add_system_ram_resources);
576
577#ifdef CONFIG_STRICT_DEVMEM
578/*
579 * devmem_is_allowed(): check to see if /dev/mem access to a certain address
580 * is valid. The argument is a physical page number.
581 *
582 * Access has to be given to non-kernel-ram areas as well, these contain the
583 * PCI mmio resources as well as potential bios/acpi data regions.
584 */
585int devmem_is_allowed(unsigned long pfn)
586{
587 if (page_is_rtas_user_buf(pfn))
588 return 1;
589 if (iomem_is_exclusive(PFN_PHYS(pfn)))
590 return 0;
591 if (!page_is_ram(pfn))
592 return 1;
593 return 0;
594}
595#endif /* CONFIG_STRICT_DEVMEM */