xref: /openbmc/linux/arch/x86/mm/numa_32.c (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
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/mm.h>
26 #include <linux/bootmem.h>
27 #include <linux/mmzone.h>
28 #include <linux/highmem.h>
29 #include <linux/initrd.h>
30 #include <linux/nodemask.h>
31 #include <linux/module.h>
32 #include <linux/kexec.h>
33 #include <linux/pfn.h>
34 #include <linux/swap.h>
35 #include <linux/acpi.h>
36 
37 #include <asm/e820.h>
38 #include <asm/setup.h>
39 #include <asm/mmzone.h>
40 #include <asm/bios_ebda.h>
41 #include <asm/proto.h>
42 
43 struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
44 EXPORT_SYMBOL(node_data);
45 
46 /*
47  * numa interface - we expect the numa architecture specific code to have
48  *                  populated the following initialisation.
49  *
50  * 1) node_online_map  - the map of all nodes configured (online) in the system
51  * 2) node_start_pfn   - the starting page frame number for a node
52  * 3) node_end_pfn     - the ending page fram number for a node
53  */
54 unsigned long node_start_pfn[MAX_NUMNODES] __read_mostly;
55 unsigned long node_end_pfn[MAX_NUMNODES] __read_mostly;
56 
57 
58 #ifdef CONFIG_DISCONTIGMEM
59 /*
60  * 4) physnode_map     - the mapping between a pfn and owning node
61  * physnode_map keeps track of the physical memory layout of a generic
62  * numa node on a 64Mb break (each element of the array will
63  * represent 64Mb of memory and will be marked by the node id.  so,
64  * if the first gig is on node 0, and the second gig is on node 1
65  * physnode_map will contain:
66  *
67  *     physnode_map[0-15] = 0;
68  *     physnode_map[16-31] = 1;
69  *     physnode_map[32- ] = -1;
70  */
71 s8 physnode_map[MAX_ELEMENTS] __read_mostly = { [0 ... (MAX_ELEMENTS - 1)] = -1};
72 EXPORT_SYMBOL(physnode_map);
73 
74 void memory_present(int nid, unsigned long start, unsigned long end)
75 {
76 	unsigned long pfn;
77 
78 	printk(KERN_INFO "Node: %d, start_pfn: %lx, end_pfn: %lx\n",
79 			nid, start, end);
80 	printk(KERN_DEBUG "  Setting physnode_map array to node %d for pfns:\n", nid);
81 	printk(KERN_DEBUG "  ");
82 	for (pfn = start; pfn < end; pfn += PAGES_PER_ELEMENT) {
83 		physnode_map[pfn / PAGES_PER_ELEMENT] = nid;
84 		printk(KERN_CONT "%lx ", pfn);
85 	}
86 	printk(KERN_CONT "\n");
87 }
88 
89 unsigned long node_memmap_size_bytes(int nid, unsigned long start_pfn,
90 					      unsigned long end_pfn)
91 {
92 	unsigned long nr_pages = end_pfn - start_pfn;
93 
94 	if (!nr_pages)
95 		return 0;
96 
97 	return (nr_pages + 1) * sizeof(struct page);
98 }
99 #endif
100 
101 extern unsigned long find_max_low_pfn(void);
102 extern unsigned long highend_pfn, highstart_pfn;
103 
104 #define LARGE_PAGE_BYTES (PTRS_PER_PTE * PAGE_SIZE)
105 
106 unsigned long node_remap_size[MAX_NUMNODES];
107 static void *node_remap_start_vaddr[MAX_NUMNODES];
108 void set_pmd_pfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags);
109 
110 static unsigned long kva_start_pfn;
111 static unsigned long kva_pages;
112 /*
113  * FLAT - support for basic PC memory model with discontig enabled, essentially
114  *        a single node with all available processors in it with a flat
115  *        memory map.
116  */
117 int __init get_memcfg_numa_flat(void)
118 {
119 	printk(KERN_DEBUG "NUMA - single node, flat memory mode\n");
120 
121 	node_start_pfn[0] = 0;
122 	node_end_pfn[0] = max_pfn;
123 	e820_register_active_regions(0, 0, max_pfn);
124 	memory_present(0, 0, max_pfn);
125 	node_remap_size[0] = node_memmap_size_bytes(0, 0, max_pfn);
126 
127         /* Indicate there is one node available. */
128 	nodes_clear(node_online_map);
129 	node_set_online(0);
130 	return 1;
131 }
132 
133 /*
134  * Find the highest page frame number we have available for the node
135  */
136 static void __init propagate_e820_map_node(int nid)
137 {
138 	if (node_end_pfn[nid] > max_pfn)
139 		node_end_pfn[nid] = max_pfn;
140 	/*
141 	 * if a user has given mem=XXXX, then we need to make sure
142 	 * that the node _starts_ before that, too, not just ends
143 	 */
144 	if (node_start_pfn[nid] > max_pfn)
145 		node_start_pfn[nid] = max_pfn;
146 	BUG_ON(node_start_pfn[nid] > node_end_pfn[nid]);
147 }
148 
149 /*
150  * Allocate memory for the pg_data_t for this node via a crude pre-bootmem
151  * method.  For node zero take this from the bottom of memory, for
152  * subsequent nodes place them at node_remap_start_vaddr which contains
153  * node local data in physically node local memory.  See setup_memory()
154  * for details.
155  */
156 static void __init allocate_pgdat(int nid)
157 {
158 	char buf[16];
159 
160 	if (node_has_online_mem(nid) && node_remap_start_vaddr[nid])
161 		NODE_DATA(nid) = (pg_data_t *)node_remap_start_vaddr[nid];
162 	else {
163 		unsigned long pgdat_phys;
164 		pgdat_phys = find_e820_area(min_low_pfn<<PAGE_SHIFT,
165 				 max_pfn_mapped<<PAGE_SHIFT,
166 				 sizeof(pg_data_t),
167 				 PAGE_SIZE);
168 		NODE_DATA(nid) = (pg_data_t *)(pfn_to_kaddr(pgdat_phys>>PAGE_SHIFT));
169 		memset(buf, 0, sizeof(buf));
170 		sprintf(buf, "NODE_DATA %d",  nid);
171 		reserve_early(pgdat_phys, pgdat_phys + sizeof(pg_data_t), buf);
172 	}
173 	printk(KERN_DEBUG "allocate_pgdat: node %d NODE_DATA %08lx\n",
174 		nid, (unsigned long)NODE_DATA(nid));
175 }
176 
177 /*
178  * In the DISCONTIGMEM and SPARSEMEM memory model, a portion of the kernel
179  * virtual address space (KVA) is reserved and portions of nodes are mapped
180  * using it. This is to allow node-local memory to be allocated for
181  * structures that would normally require ZONE_NORMAL. The memory is
182  * allocated with alloc_remap() and callers should be prepared to allocate
183  * from the bootmem allocator instead.
184  */
185 static unsigned long node_remap_start_pfn[MAX_NUMNODES];
186 static void *node_remap_end_vaddr[MAX_NUMNODES];
187 static void *node_remap_alloc_vaddr[MAX_NUMNODES];
188 static unsigned long node_remap_offset[MAX_NUMNODES];
189 
190 void *alloc_remap(int nid, unsigned long size)
191 {
192 	void *allocation = node_remap_alloc_vaddr[nid];
193 
194 	size = ALIGN(size, L1_CACHE_BYTES);
195 
196 	if (!allocation || (allocation + size) >= node_remap_end_vaddr[nid])
197 		return 0;
198 
199 	node_remap_alloc_vaddr[nid] += size;
200 	memset(allocation, 0, size);
201 
202 	return allocation;
203 }
204 
205 static void __init remap_numa_kva(void)
206 {
207 	void *vaddr;
208 	unsigned long pfn;
209 	int node;
210 
211 	for_each_online_node(node) {
212 		printk(KERN_DEBUG "remap_numa_kva: node %d\n", node);
213 		for (pfn=0; pfn < node_remap_size[node]; pfn += PTRS_PER_PTE) {
214 			vaddr = node_remap_start_vaddr[node]+(pfn<<PAGE_SHIFT);
215 			printk(KERN_DEBUG "remap_numa_kva: %08lx to pfn %08lx\n",
216 				(unsigned long)vaddr,
217 				node_remap_start_pfn[node] + pfn);
218 			set_pmd_pfn((ulong) vaddr,
219 				node_remap_start_pfn[node] + pfn,
220 				PAGE_KERNEL_LARGE);
221 		}
222 	}
223 }
224 
225 static unsigned long calculate_numa_remap_pages(void)
226 {
227 	int nid;
228 	unsigned long size, reserve_pages = 0;
229 
230 	for_each_online_node(nid) {
231 		u64 node_kva_target;
232 		u64 node_kva_final;
233 
234 		/*
235 		 * The acpi/srat node info can show hot-add memroy zones
236 		 * where memory could be added but not currently present.
237 		 */
238 		printk(KERN_DEBUG "node %d pfn: [%lx - %lx]\n",
239 			nid, node_start_pfn[nid], node_end_pfn[nid]);
240 		if (node_start_pfn[nid] > max_pfn)
241 			continue;
242 		if (!node_end_pfn[nid])
243 			continue;
244 		if (node_end_pfn[nid] > max_pfn)
245 			node_end_pfn[nid] = max_pfn;
246 
247 		/* ensure the remap includes space for the pgdat. */
248 		size = node_remap_size[nid] + sizeof(pg_data_t);
249 
250 		/* convert size to large (pmd size) pages, rounding up */
251 		size = (size + LARGE_PAGE_BYTES - 1) / LARGE_PAGE_BYTES;
252 		/* now the roundup is correct, convert to PAGE_SIZE pages */
253 		size = size * PTRS_PER_PTE;
254 
255 		node_kva_target = round_down(node_end_pfn[nid] - size,
256 						 PTRS_PER_PTE);
257 		node_kva_target <<= PAGE_SHIFT;
258 		do {
259 			node_kva_final = find_e820_area(node_kva_target,
260 					((u64)node_end_pfn[nid])<<PAGE_SHIFT,
261 						((u64)size)<<PAGE_SHIFT,
262 						LARGE_PAGE_BYTES);
263 			node_kva_target -= LARGE_PAGE_BYTES;
264 		} while (node_kva_final == -1ULL &&
265 			 (node_kva_target>>PAGE_SHIFT) > (node_start_pfn[nid]));
266 
267 		if (node_kva_final == -1ULL)
268 			panic("Can not get kva ram\n");
269 
270 		node_remap_size[nid] = size;
271 		node_remap_offset[nid] = reserve_pages;
272 		reserve_pages += size;
273 		printk(KERN_DEBUG "Reserving %ld pages of KVA for lmem_map of"
274 				  " node %d at %llx\n",
275 				size, nid, node_kva_final>>PAGE_SHIFT);
276 
277 		/*
278 		 *  prevent kva address below max_low_pfn want it on system
279 		 *  with less memory later.
280 		 *  layout will be: KVA address , KVA RAM
281 		 *
282 		 *  we are supposed to only record the one less then max_low_pfn
283 		 *  but we could have some hole in high memory, and it will only
284 		 *  check page_is_ram(pfn) && !page_is_reserved_early(pfn) to decide
285 		 *  to use it as free.
286 		 *  So reserve_early here, hope we don't run out of that array
287 		 */
288 		reserve_early(node_kva_final,
289 			      node_kva_final+(((u64)size)<<PAGE_SHIFT),
290 			      "KVA RAM");
291 
292 		node_remap_start_pfn[nid] = node_kva_final>>PAGE_SHIFT;
293 		remove_active_range(nid, node_remap_start_pfn[nid],
294 					 node_remap_start_pfn[nid] + size);
295 	}
296 	printk(KERN_INFO "Reserving total of %lx pages for numa KVA remap\n",
297 			reserve_pages);
298 	return reserve_pages;
299 }
300 
301 static void init_remap_allocator(int nid)
302 {
303 	node_remap_start_vaddr[nid] = pfn_to_kaddr(
304 			kva_start_pfn + node_remap_offset[nid]);
305 	node_remap_end_vaddr[nid] = node_remap_start_vaddr[nid] +
306 		(node_remap_size[nid] * PAGE_SIZE);
307 	node_remap_alloc_vaddr[nid] = node_remap_start_vaddr[nid] +
308 		ALIGN(sizeof(pg_data_t), PAGE_SIZE);
309 
310 	printk(KERN_DEBUG "node %d will remap to vaddr %08lx - %08lx\n", nid,
311 		(ulong) node_remap_start_vaddr[nid],
312 		(ulong) node_remap_end_vaddr[nid]);
313 }
314 
315 void __init initmem_init(unsigned long start_pfn,
316 				  unsigned long end_pfn)
317 {
318 	int nid;
319 	long kva_target_pfn;
320 
321 	/*
322 	 * When mapping a NUMA machine we allocate the node_mem_map arrays
323 	 * from node local memory.  They are then mapped directly into KVA
324 	 * between zone normal and vmalloc space.  Calculate the size of
325 	 * this space and use it to adjust the boundary between ZONE_NORMAL
326 	 * and ZONE_HIGHMEM.
327 	 */
328 
329 	get_memcfg_numa();
330 
331 	kva_pages = roundup(calculate_numa_remap_pages(), PTRS_PER_PTE);
332 
333 	kva_target_pfn = round_down(max_low_pfn - kva_pages, PTRS_PER_PTE);
334 	do {
335 		kva_start_pfn = find_e820_area(kva_target_pfn<<PAGE_SHIFT,
336 					max_low_pfn<<PAGE_SHIFT,
337 					kva_pages<<PAGE_SHIFT,
338 					PTRS_PER_PTE<<PAGE_SHIFT) >> PAGE_SHIFT;
339 		kva_target_pfn -= PTRS_PER_PTE;
340 	} while (kva_start_pfn == -1UL && kva_target_pfn > min_low_pfn);
341 
342 	if (kva_start_pfn == -1UL)
343 		panic("Can not get kva space\n");
344 
345 	printk(KERN_INFO "kva_start_pfn ~ %lx max_low_pfn ~ %lx\n",
346 		kva_start_pfn, max_low_pfn);
347 	printk(KERN_INFO "max_pfn = %lx\n", max_pfn);
348 
349 	/* avoid clash with initrd */
350 	reserve_early(kva_start_pfn<<PAGE_SHIFT,
351 		      (kva_start_pfn + kva_pages)<<PAGE_SHIFT,
352 		     "KVA PG");
353 #ifdef CONFIG_HIGHMEM
354 	highstart_pfn = highend_pfn = max_pfn;
355 	if (max_pfn > max_low_pfn)
356 		highstart_pfn = max_low_pfn;
357 	printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
358 	       pages_to_mb(highend_pfn - highstart_pfn));
359 	num_physpages = highend_pfn;
360 	high_memory = (void *) __va(highstart_pfn * PAGE_SIZE - 1) + 1;
361 #else
362 	num_physpages = max_low_pfn;
363 	high_memory = (void *) __va(max_low_pfn * PAGE_SIZE - 1) + 1;
364 #endif
365 	printk(KERN_NOTICE "%ldMB LOWMEM available.\n",
366 			pages_to_mb(max_low_pfn));
367 	printk(KERN_DEBUG "max_low_pfn = %lx, highstart_pfn = %lx\n",
368 			max_low_pfn, highstart_pfn);
369 
370 	printk(KERN_DEBUG "Low memory ends at vaddr %08lx\n",
371 			(ulong) pfn_to_kaddr(max_low_pfn));
372 	for_each_online_node(nid) {
373 		init_remap_allocator(nid);
374 
375 		allocate_pgdat(nid);
376 	}
377 	remap_numa_kva();
378 
379 	printk(KERN_DEBUG "High memory starts at vaddr %08lx\n",
380 			(ulong) pfn_to_kaddr(highstart_pfn));
381 	for_each_online_node(nid)
382 		propagate_e820_map_node(nid);
383 
384 	for_each_online_node(nid)
385 		memset(NODE_DATA(nid), 0, sizeof(struct pglist_data));
386 
387 	NODE_DATA(0)->bdata = &bootmem_node_data[0];
388 	setup_bootmem_allocator();
389 }
390 
391 void __init set_highmem_pages_init(void)
392 {
393 #ifdef CONFIG_HIGHMEM
394 	struct zone *zone;
395 	int nid;
396 
397 	for_each_zone(zone) {
398 		unsigned long zone_start_pfn, zone_end_pfn;
399 
400 		if (!is_highmem(zone))
401 			continue;
402 
403 		zone_start_pfn = zone->zone_start_pfn;
404 		zone_end_pfn = zone_start_pfn + zone->spanned_pages;
405 
406 		nid = zone_to_nid(zone);
407 		printk(KERN_INFO "Initializing %s for node %d (%08lx:%08lx)\n",
408 				zone->name, nid, zone_start_pfn, zone_end_pfn);
409 
410 		add_highpages_with_active_regions(nid, zone_start_pfn,
411 				 zone_end_pfn);
412 	}
413 	totalram_pages += totalhigh_pages;
414 #endif
415 }
416 
417 #ifdef CONFIG_MEMORY_HOTPLUG
418 static int paddr_to_nid(u64 addr)
419 {
420 	int nid;
421 	unsigned long pfn = PFN_DOWN(addr);
422 
423 	for_each_node(nid)
424 		if (node_start_pfn[nid] <= pfn &&
425 		    pfn < node_end_pfn[nid])
426 			return nid;
427 
428 	return -1;
429 }
430 
431 /*
432  * This function is used to ask node id BEFORE memmap and mem_section's
433  * initialization (pfn_to_nid() can't be used yet).
434  * If _PXM is not defined on ACPI's DSDT, node id must be found by this.
435  */
436 int memory_add_physaddr_to_nid(u64 addr)
437 {
438 	int nid = paddr_to_nid(addr);
439 	return (nid >= 0) ? nid : 0;
440 }
441 
442 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
443 #endif
444 
445