1 /*
2 * Written by: Patricia Gaughen <gone@us.ibm.com>, IBM Corporation
3 * August 2002: added remote node KVA remap - Martin J. Bligh
4 *
5 * Copyright (C) 2002, IBM Corp.
6 *
7 * All rights reserved.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
17 * NON INFRINGEMENT. See the GNU General Public License for more
18 * details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 */
24
25 #include <linux/bootmem.h>
26 #include <linux/memblock.h>
27 #include <linux/module.h>
28
29 #include "numa_internal.h"
30
31 #ifdef CONFIG_DISCONTIGMEM
32 /*
33 * 4) physnode_map - the mapping between a pfn and owning node
34 * physnode_map keeps track of the physical memory layout of a generic
35 * numa node on a 64Mb break (each element of the array will
36 * represent 64Mb of memory and will be marked by the node id. so,
37 * if the first gig is on node 0, and the second gig is on node 1
38 * physnode_map will contain:
39 *
40 * physnode_map[0-15] = 0;
41 * physnode_map[16-31] = 1;
42 * physnode_map[32- ] = -1;
43 */
44 s8 physnode_map[MAX_SECTIONS] __read_mostly = { [0 ... (MAX_SECTIONS - 1)] = -1};
45 EXPORT_SYMBOL(physnode_map);
46
memory_present(int nid,unsigned long start,unsigned long end)47 void memory_present(int nid, unsigned long start, unsigned long end)
48 {
49 unsigned long pfn;
50
51 printk(KERN_INFO "Node: %d, start_pfn: %lx, end_pfn: %lx\n",
52 nid, start, end);
53 printk(KERN_DEBUG " Setting physnode_map array to node %d for pfns:\n", nid);
54 printk(KERN_DEBUG " ");
55 for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) {
56 physnode_map[pfn / PAGES_PER_SECTION] = nid;
57 printk(KERN_CONT "%lx ", pfn);
58 }
59 printk(KERN_CONT "\n");
60 }
61
node_memmap_size_bytes(int nid,unsigned long start_pfn,unsigned long end_pfn)62 unsigned long node_memmap_size_bytes(int nid, unsigned long start_pfn,
63 unsigned long end_pfn)
64 {
65 unsigned long nr_pages = end_pfn - start_pfn;
66
67 if (!nr_pages)
68 return 0;
69
70 return (nr_pages + 1) * sizeof(struct page);
71 }
72 #endif
73
74 extern unsigned long highend_pfn, highstart_pfn;
75
76 #define LARGE_PAGE_BYTES (PTRS_PER_PTE * PAGE_SIZE)
77
78 static void *node_remap_start_vaddr[MAX_NUMNODES];
79 void set_pmd_pfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags);
80
81 /*
82 * Remap memory allocator
83 */
84 static unsigned long node_remap_start_pfn[MAX_NUMNODES];
85 static void *node_remap_end_vaddr[MAX_NUMNODES];
86 static void *node_remap_alloc_vaddr[MAX_NUMNODES];
87
88 /**
89 * alloc_remap - Allocate remapped memory
90 * @nid: NUMA node to allocate memory from
91 * @size: The size of allocation
92 *
93 * Allocate @size bytes from the remap area of NUMA node @nid. The
94 * size of the remap area is predetermined by init_alloc_remap() and
95 * only the callers considered there should call this function. For
96 * more info, please read the comment on top of init_alloc_remap().
97 *
98 * The caller must be ready to handle allocation failure from this
99 * function and fall back to regular memory allocator in such cases.
100 *
101 * CONTEXT:
102 * Single CPU early boot context.
103 *
104 * RETURNS:
105 * Pointer to the allocated memory on success, %NULL on failure.
106 */
alloc_remap(int nid,unsigned long size)107 void *alloc_remap(int nid, unsigned long size)
108 {
109 void *allocation = node_remap_alloc_vaddr[nid];
110
111 size = ALIGN(size, L1_CACHE_BYTES);
112
113 if (!allocation || (allocation + size) > node_remap_end_vaddr[nid])
114 return NULL;
115
116 node_remap_alloc_vaddr[nid] += size;
117 memset(allocation, 0, size);
118
119 return allocation;
120 }
121
122 #ifdef CONFIG_HIBERNATION
123 /**
124 * resume_map_numa_kva - add KVA mapping to the temporary page tables created
125 * during resume from hibernation
126 * @pgd_base - temporary resume page directory
127 */
resume_map_numa_kva(pgd_t * pgd_base)128 void resume_map_numa_kva(pgd_t *pgd_base)
129 {
130 int node;
131
132 for_each_online_node(node) {
133 unsigned long start_va, start_pfn, nr_pages, pfn;
134
135 start_va = (unsigned long)node_remap_start_vaddr[node];
136 start_pfn = node_remap_start_pfn[node];
137 nr_pages = (node_remap_end_vaddr[node] -
138 node_remap_start_vaddr[node]) >> PAGE_SHIFT;
139
140 printk(KERN_DEBUG "%s: node %d\n", __func__, node);
141
142 for (pfn = 0; pfn < nr_pages; pfn += PTRS_PER_PTE) {
143 unsigned long vaddr = start_va + (pfn << PAGE_SHIFT);
144 pgd_t *pgd = pgd_base + pgd_index(vaddr);
145 pud_t *pud = pud_offset(pgd, vaddr);
146 pmd_t *pmd = pmd_offset(pud, vaddr);
147
148 set_pmd(pmd, pfn_pmd(start_pfn + pfn,
149 PAGE_KERNEL_LARGE_EXEC));
150
151 printk(KERN_DEBUG "%s: %08lx -> pfn %08lx\n",
152 __func__, vaddr, start_pfn + pfn);
153 }
154 }
155 }
156 #endif
157
158 /**
159 * init_alloc_remap - Initialize remap allocator for a NUMA node
160 * @nid: NUMA node to initizlie remap allocator for
161 *
162 * NUMA nodes may end up without any lowmem. As allocating pgdat and
163 * memmap on a different node with lowmem is inefficient, a special
164 * remap allocator is implemented which can be used by alloc_remap().
165 *
166 * For each node, the amount of memory which will be necessary for
167 * pgdat and memmap is calculated and two memory areas of the size are
168 * allocated - one in the node and the other in lowmem; then, the area
169 * in the node is remapped to the lowmem area.
170 *
171 * As pgdat and memmap must be allocated in lowmem anyway, this
172 * doesn't waste lowmem address space; however, the actual lowmem
173 * which gets remapped over is wasted. The amount shouldn't be
174 * problematic on machines this feature will be used.
175 *
176 * Initialization failure isn't fatal. alloc_remap() is used
177 * opportunistically and the callers will fall back to other memory
178 * allocation mechanisms on failure.
179 */
init_alloc_remap(int nid,u64 start,u64 end)180 void __init init_alloc_remap(int nid, u64 start, u64 end)
181 {
182 unsigned long start_pfn = start >> PAGE_SHIFT;
183 unsigned long end_pfn = end >> PAGE_SHIFT;
184 unsigned long size, pfn;
185 u64 node_pa, remap_pa;
186 void *remap_va;
187
188 /*
189 * The acpi/srat node info can show hot-add memroy zones where
190 * memory could be added but not currently present.
191 */
192 printk(KERN_DEBUG "node %d pfn: [%lx - %lx]\n",
193 nid, start_pfn, end_pfn);
194
195 /* calculate the necessary space aligned to large page size */
196 size = node_memmap_size_bytes(nid, start_pfn, end_pfn);
197 size += ALIGN(sizeof(pg_data_t), PAGE_SIZE);
198 size = ALIGN(size, LARGE_PAGE_BYTES);
199
200 /* allocate node memory and the lowmem remap area */
201 node_pa = memblock_find_in_range(start, end, size, LARGE_PAGE_BYTES);
202 if (!node_pa) {
203 pr_warning("remap_alloc: failed to allocate %lu bytes for node %d\n",
204 size, nid);
205 return;
206 }
207 memblock_reserve(node_pa, size);
208
209 remap_pa = memblock_find_in_range(min_low_pfn << PAGE_SHIFT,
210 max_low_pfn << PAGE_SHIFT,
211 size, LARGE_PAGE_BYTES);
212 if (!remap_pa) {
213 pr_warning("remap_alloc: failed to allocate %lu bytes remap area for node %d\n",
214 size, nid);
215 memblock_free(node_pa, size);
216 return;
217 }
218 memblock_reserve(remap_pa, size);
219 remap_va = phys_to_virt(remap_pa);
220
221 /* perform actual remap */
222 for (pfn = 0; pfn < size >> PAGE_SHIFT; pfn += PTRS_PER_PTE)
223 set_pmd_pfn((unsigned long)remap_va + (pfn << PAGE_SHIFT),
224 (node_pa >> PAGE_SHIFT) + pfn,
225 PAGE_KERNEL_LARGE);
226
227 /* initialize remap allocator parameters */
228 node_remap_start_pfn[nid] = node_pa >> PAGE_SHIFT;
229 node_remap_start_vaddr[nid] = remap_va;
230 node_remap_end_vaddr[nid] = remap_va + size;
231 node_remap_alloc_vaddr[nid] = remap_va;
232
233 printk(KERN_DEBUG "remap_alloc: node %d [%08llx-%08llx) -> [%p-%p)\n",
234 nid, node_pa, node_pa + size, remap_va, remap_va + size);
235 }
236
initmem_init(void)237 void __init initmem_init(void)
238 {
239 x86_numa_init();
240
241 #ifdef CONFIG_HIGHMEM
242 highstart_pfn = highend_pfn = max_pfn;
243 if (max_pfn > max_low_pfn)
244 highstart_pfn = max_low_pfn;
245 printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
246 pages_to_mb(highend_pfn - highstart_pfn));
247 num_physpages = highend_pfn;
248 high_memory = (void *) __va(highstart_pfn * PAGE_SIZE - 1) + 1;
249 #else
250 num_physpages = max_low_pfn;
251 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE - 1) + 1;
252 #endif
253 printk(KERN_NOTICE "%ldMB LOWMEM available.\n",
254 pages_to_mb(max_low_pfn));
255 printk(KERN_DEBUG "max_low_pfn = %lx, highstart_pfn = %lx\n",
256 max_low_pfn, highstart_pfn);
257
258 printk(KERN_DEBUG "Low memory ends at vaddr %08lx\n",
259 (ulong) pfn_to_kaddr(max_low_pfn));
260
261 printk(KERN_DEBUG "High memory starts at vaddr %08lx\n",
262 (ulong) pfn_to_kaddr(highstart_pfn));
263
264 setup_bootmem_allocator();
265 }
266