xref: /openbmc/linux/arch/ia64/mm/discontig.c (revision fca3aa16)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2000, 2003 Silicon Graphics, Inc.  All rights reserved.
4  * Copyright (c) 2001 Intel Corp.
5  * Copyright (c) 2001 Tony Luck <tony.luck@intel.com>
6  * Copyright (c) 2002 NEC Corp.
7  * Copyright (c) 2002 Kimio Suganuma <k-suganuma@da.jp.nec.com>
8  * Copyright (c) 2004 Silicon Graphics, Inc
9  *	Russ Anderson <rja@sgi.com>
10  *	Jesse Barnes <jbarnes@sgi.com>
11  *	Jack Steiner <steiner@sgi.com>
12  */
13 
14 /*
15  * Platform initialization for Discontig Memory
16  */
17 
18 #include <linux/kernel.h>
19 #include <linux/mm.h>
20 #include <linux/nmi.h>
21 #include <linux/swap.h>
22 #include <linux/bootmem.h>
23 #include <linux/acpi.h>
24 #include <linux/efi.h>
25 #include <linux/nodemask.h>
26 #include <linux/slab.h>
27 #include <asm/pgalloc.h>
28 #include <asm/tlb.h>
29 #include <asm/meminit.h>
30 #include <asm/numa.h>
31 #include <asm/sections.h>
32 
33 /*
34  * Track per-node information needed to setup the boot memory allocator, the
35  * per-node areas, and the real VM.
36  */
37 struct early_node_data {
38 	struct ia64_node_data *node_data;
39 	unsigned long pernode_addr;
40 	unsigned long pernode_size;
41 #ifdef CONFIG_ZONE_DMA32
42 	unsigned long num_dma_physpages;
43 #endif
44 	unsigned long min_pfn;
45 	unsigned long max_pfn;
46 };
47 
48 static struct early_node_data mem_data[MAX_NUMNODES] __initdata;
49 static nodemask_t memory_less_mask __initdata;
50 
51 pg_data_t *pgdat_list[MAX_NUMNODES];
52 
53 /*
54  * To prevent cache aliasing effects, align per-node structures so that they
55  * start at addresses that are strided by node number.
56  */
57 #define MAX_NODE_ALIGN_OFFSET	(32 * 1024 * 1024)
58 #define NODEDATA_ALIGN(addr, node)						\
59 	((((addr) + 1024*1024-1) & ~(1024*1024-1)) + 				\
60 	     (((node)*PERCPU_PAGE_SIZE) & (MAX_NODE_ALIGN_OFFSET - 1)))
61 
62 /**
63  * build_node_maps - callback to setup bootmem structs for each node
64  * @start: physical start of range
65  * @len: length of range
66  * @node: node where this range resides
67  *
68  * We allocate a struct bootmem_data for each piece of memory that we wish to
69  * treat as a virtually contiguous block (i.e. each node). Each such block
70  * must start on an %IA64_GRANULE_SIZE boundary, so we round the address down
71  * if necessary.  Any non-existent pages will simply be part of the virtual
72  * memmap.  We also update min_low_pfn and max_low_pfn here as we receive
73  * memory ranges from the caller.
74  */
75 static int __init build_node_maps(unsigned long start, unsigned long len,
76 				  int node)
77 {
78 	unsigned long spfn, epfn, end = start + len;
79 	struct bootmem_data *bdp = &bootmem_node_data[node];
80 
81 	epfn = GRANULEROUNDUP(end) >> PAGE_SHIFT;
82 	spfn = GRANULEROUNDDOWN(start) >> PAGE_SHIFT;
83 
84 	if (!bdp->node_low_pfn) {
85 		bdp->node_min_pfn = spfn;
86 		bdp->node_low_pfn = epfn;
87 	} else {
88 		bdp->node_min_pfn = min(spfn, bdp->node_min_pfn);
89 		bdp->node_low_pfn = max(epfn, bdp->node_low_pfn);
90 	}
91 
92 	return 0;
93 }
94 
95 /**
96  * early_nr_cpus_node - return number of cpus on a given node
97  * @node: node to check
98  *
99  * Count the number of cpus on @node.  We can't use nr_cpus_node() yet because
100  * acpi_boot_init() (which builds the node_to_cpu_mask array) hasn't been
101  * called yet.  Note that node 0 will also count all non-existent cpus.
102  */
103 static int __meminit early_nr_cpus_node(int node)
104 {
105 	int cpu, n = 0;
106 
107 	for_each_possible_early_cpu(cpu)
108 		if (node == node_cpuid[cpu].nid)
109 			n++;
110 
111 	return n;
112 }
113 
114 /**
115  * compute_pernodesize - compute size of pernode data
116  * @node: the node id.
117  */
118 static unsigned long __meminit compute_pernodesize(int node)
119 {
120 	unsigned long pernodesize = 0, cpus;
121 
122 	cpus = early_nr_cpus_node(node);
123 	pernodesize += PERCPU_PAGE_SIZE * cpus;
124 	pernodesize += node * L1_CACHE_BYTES;
125 	pernodesize += L1_CACHE_ALIGN(sizeof(pg_data_t));
126 	pernodesize += L1_CACHE_ALIGN(sizeof(struct ia64_node_data));
127 	pernodesize += L1_CACHE_ALIGN(sizeof(pg_data_t));
128 	pernodesize = PAGE_ALIGN(pernodesize);
129 	return pernodesize;
130 }
131 
132 /**
133  * per_cpu_node_setup - setup per-cpu areas on each node
134  * @cpu_data: per-cpu area on this node
135  * @node: node to setup
136  *
137  * Copy the static per-cpu data into the region we just set aside and then
138  * setup __per_cpu_offset for each CPU on this node.  Return a pointer to
139  * the end of the area.
140  */
141 static void *per_cpu_node_setup(void *cpu_data, int node)
142 {
143 #ifdef CONFIG_SMP
144 	int cpu;
145 
146 	for_each_possible_early_cpu(cpu) {
147 		void *src = cpu == 0 ? __cpu0_per_cpu : __phys_per_cpu_start;
148 
149 		if (node != node_cpuid[cpu].nid)
150 			continue;
151 
152 		memcpy(__va(cpu_data), src, __per_cpu_end - __per_cpu_start);
153 		__per_cpu_offset[cpu] = (char *)__va(cpu_data) -
154 			__per_cpu_start;
155 
156 		/*
157 		 * percpu area for cpu0 is moved from the __init area
158 		 * which is setup by head.S and used till this point.
159 		 * Update ar.k3.  This move is ensures that percpu
160 		 * area for cpu0 is on the correct node and its
161 		 * virtual address isn't insanely far from other
162 		 * percpu areas which is important for congruent
163 		 * percpu allocator.
164 		 */
165 		if (cpu == 0)
166 			ia64_set_kr(IA64_KR_PER_CPU_DATA,
167 				    (unsigned long)cpu_data -
168 				    (unsigned long)__per_cpu_start);
169 
170 		cpu_data += PERCPU_PAGE_SIZE;
171 	}
172 #endif
173 	return cpu_data;
174 }
175 
176 #ifdef CONFIG_SMP
177 /**
178  * setup_per_cpu_areas - setup percpu areas
179  *
180  * Arch code has already allocated and initialized percpu areas.  All
181  * this function has to do is to teach the determined layout to the
182  * dynamic percpu allocator, which happens to be more complex than
183  * creating whole new ones using helpers.
184  */
185 void __init setup_per_cpu_areas(void)
186 {
187 	struct pcpu_alloc_info *ai;
188 	struct pcpu_group_info *uninitialized_var(gi);
189 	unsigned int *cpu_map;
190 	void *base;
191 	unsigned long base_offset;
192 	unsigned int cpu;
193 	ssize_t static_size, reserved_size, dyn_size;
194 	int node, prev_node, unit, nr_units, rc;
195 
196 	ai = pcpu_alloc_alloc_info(MAX_NUMNODES, nr_cpu_ids);
197 	if (!ai)
198 		panic("failed to allocate pcpu_alloc_info");
199 	cpu_map = ai->groups[0].cpu_map;
200 
201 	/* determine base */
202 	base = (void *)ULONG_MAX;
203 	for_each_possible_cpu(cpu)
204 		base = min(base,
205 			   (void *)(__per_cpu_offset[cpu] + __per_cpu_start));
206 	base_offset = (void *)__per_cpu_start - base;
207 
208 	/* build cpu_map, units are grouped by node */
209 	unit = 0;
210 	for_each_node(node)
211 		for_each_possible_cpu(cpu)
212 			if (node == node_cpuid[cpu].nid)
213 				cpu_map[unit++] = cpu;
214 	nr_units = unit;
215 
216 	/* set basic parameters */
217 	static_size = __per_cpu_end - __per_cpu_start;
218 	reserved_size = PERCPU_MODULE_RESERVE;
219 	dyn_size = PERCPU_PAGE_SIZE - static_size - reserved_size;
220 	if (dyn_size < 0)
221 		panic("percpu area overflow static=%zd reserved=%zd\n",
222 		      static_size, reserved_size);
223 
224 	ai->static_size		= static_size;
225 	ai->reserved_size	= reserved_size;
226 	ai->dyn_size		= dyn_size;
227 	ai->unit_size		= PERCPU_PAGE_SIZE;
228 	ai->atom_size		= PAGE_SIZE;
229 	ai->alloc_size		= PERCPU_PAGE_SIZE;
230 
231 	/*
232 	 * CPUs are put into groups according to node.  Walk cpu_map
233 	 * and create new groups at node boundaries.
234 	 */
235 	prev_node = -1;
236 	ai->nr_groups = 0;
237 	for (unit = 0; unit < nr_units; unit++) {
238 		cpu = cpu_map[unit];
239 		node = node_cpuid[cpu].nid;
240 
241 		if (node == prev_node) {
242 			gi->nr_units++;
243 			continue;
244 		}
245 		prev_node = node;
246 
247 		gi = &ai->groups[ai->nr_groups++];
248 		gi->nr_units		= 1;
249 		gi->base_offset		= __per_cpu_offset[cpu] + base_offset;
250 		gi->cpu_map		= &cpu_map[unit];
251 	}
252 
253 	rc = pcpu_setup_first_chunk(ai, base);
254 	if (rc)
255 		panic("failed to setup percpu area (err=%d)", rc);
256 
257 	pcpu_free_alloc_info(ai);
258 }
259 #endif
260 
261 /**
262  * fill_pernode - initialize pernode data.
263  * @node: the node id.
264  * @pernode: physical address of pernode data
265  * @pernodesize: size of the pernode data
266  */
267 static void __init fill_pernode(int node, unsigned long pernode,
268 	unsigned long pernodesize)
269 {
270 	void *cpu_data;
271 	int cpus = early_nr_cpus_node(node);
272 	struct bootmem_data *bdp = &bootmem_node_data[node];
273 
274 	mem_data[node].pernode_addr = pernode;
275 	mem_data[node].pernode_size = pernodesize;
276 	memset(__va(pernode), 0, pernodesize);
277 
278 	cpu_data = (void *)pernode;
279 	pernode += PERCPU_PAGE_SIZE * cpus;
280 	pernode += node * L1_CACHE_BYTES;
281 
282 	pgdat_list[node] = __va(pernode);
283 	pernode += L1_CACHE_ALIGN(sizeof(pg_data_t));
284 
285 	mem_data[node].node_data = __va(pernode);
286 	pernode += L1_CACHE_ALIGN(sizeof(struct ia64_node_data));
287 
288 	pgdat_list[node]->bdata = bdp;
289 	pernode += L1_CACHE_ALIGN(sizeof(pg_data_t));
290 
291 	cpu_data = per_cpu_node_setup(cpu_data, node);
292 
293 	return;
294 }
295 
296 /**
297  * find_pernode_space - allocate memory for memory map and per-node structures
298  * @start: physical start of range
299  * @len: length of range
300  * @node: node where this range resides
301  *
302  * This routine reserves space for the per-cpu data struct, the list of
303  * pg_data_ts and the per-node data struct.  Each node will have something like
304  * the following in the first chunk of addr. space large enough to hold it.
305  *
306  *    ________________________
307  *   |                        |
308  *   |~~~~~~~~~~~~~~~~~~~~~~~~| <-- NODEDATA_ALIGN(start, node) for the first
309  *   |    PERCPU_PAGE_SIZE *  |     start and length big enough
310  *   |    cpus_on_this_node   | Node 0 will also have entries for all non-existent cpus.
311  *   |------------------------|
312  *   |   local pg_data_t *    |
313  *   |------------------------|
314  *   |  local ia64_node_data  |
315  *   |------------------------|
316  *   |          ???           |
317  *   |________________________|
318  *
319  * Once this space has been set aside, the bootmem maps are initialized.  We
320  * could probably move the allocation of the per-cpu and ia64_node_data space
321  * outside of this function and use alloc_bootmem_node(), but doing it here
322  * is straightforward and we get the alignments we want so...
323  */
324 static int __init find_pernode_space(unsigned long start, unsigned long len,
325 				     int node)
326 {
327 	unsigned long spfn, epfn;
328 	unsigned long pernodesize = 0, pernode, pages, mapsize;
329 	struct bootmem_data *bdp = &bootmem_node_data[node];
330 
331 	spfn = start >> PAGE_SHIFT;
332 	epfn = (start + len) >> PAGE_SHIFT;
333 
334 	pages = bdp->node_low_pfn - bdp->node_min_pfn;
335 	mapsize = bootmem_bootmap_pages(pages) << PAGE_SHIFT;
336 
337 	/*
338 	 * Make sure this memory falls within this node's usable memory
339 	 * since we may have thrown some away in build_maps().
340 	 */
341 	if (spfn < bdp->node_min_pfn || epfn > bdp->node_low_pfn)
342 		return 0;
343 
344 	/* Don't setup this node's local space twice... */
345 	if (mem_data[node].pernode_addr)
346 		return 0;
347 
348 	/*
349 	 * Calculate total size needed, incl. what's necessary
350 	 * for good alignment and alias prevention.
351 	 */
352 	pernodesize = compute_pernodesize(node);
353 	pernode = NODEDATA_ALIGN(start, node);
354 
355 	/* Is this range big enough for what we want to store here? */
356 	if (start + len > (pernode + pernodesize + mapsize))
357 		fill_pernode(node, pernode, pernodesize);
358 
359 	return 0;
360 }
361 
362 /**
363  * free_node_bootmem - free bootmem allocator memory for use
364  * @start: physical start of range
365  * @len: length of range
366  * @node: node where this range resides
367  *
368  * Simply calls the bootmem allocator to free the specified ranged from
369  * the given pg_data_t's bdata struct.  After this function has been called
370  * for all the entries in the EFI memory map, the bootmem allocator will
371  * be ready to service allocation requests.
372  */
373 static int __init free_node_bootmem(unsigned long start, unsigned long len,
374 				    int node)
375 {
376 	free_bootmem_node(pgdat_list[node], start, len);
377 
378 	return 0;
379 }
380 
381 /**
382  * reserve_pernode_space - reserve memory for per-node space
383  *
384  * Reserve the space used by the bootmem maps & per-node space in the boot
385  * allocator so that when we actually create the real mem maps we don't
386  * use their memory.
387  */
388 static void __init reserve_pernode_space(void)
389 {
390 	unsigned long base, size, pages;
391 	struct bootmem_data *bdp;
392 	int node;
393 
394 	for_each_online_node(node) {
395 		pg_data_t *pdp = pgdat_list[node];
396 
397 		if (node_isset(node, memory_less_mask))
398 			continue;
399 
400 		bdp = pdp->bdata;
401 
402 		/* First the bootmem_map itself */
403 		pages = bdp->node_low_pfn - bdp->node_min_pfn;
404 		size = bootmem_bootmap_pages(pages) << PAGE_SHIFT;
405 		base = __pa(bdp->node_bootmem_map);
406 		reserve_bootmem_node(pdp, base, size, BOOTMEM_DEFAULT);
407 
408 		/* Now the per-node space */
409 		size = mem_data[node].pernode_size;
410 		base = __pa(mem_data[node].pernode_addr);
411 		reserve_bootmem_node(pdp, base, size, BOOTMEM_DEFAULT);
412 	}
413 }
414 
415 static void __meminit scatter_node_data(void)
416 {
417 	pg_data_t **dst;
418 	int node;
419 
420 	/*
421 	 * for_each_online_node() can't be used at here.
422 	 * node_online_map is not set for hot-added nodes at this time,
423 	 * because we are halfway through initialization of the new node's
424 	 * structures.  If for_each_online_node() is used, a new node's
425 	 * pg_data_ptrs will be not initialized. Instead of using it,
426 	 * pgdat_list[] is checked.
427 	 */
428 	for_each_node(node) {
429 		if (pgdat_list[node]) {
430 			dst = LOCAL_DATA_ADDR(pgdat_list[node])->pg_data_ptrs;
431 			memcpy(dst, pgdat_list, sizeof(pgdat_list));
432 		}
433 	}
434 }
435 
436 /**
437  * initialize_pernode_data - fixup per-cpu & per-node pointers
438  *
439  * Each node's per-node area has a copy of the global pg_data_t list, so
440  * we copy that to each node here, as well as setting the per-cpu pointer
441  * to the local node data structure.  The active_cpus field of the per-node
442  * structure gets setup by the platform_cpu_init() function later.
443  */
444 static void __init initialize_pernode_data(void)
445 {
446 	int cpu, node;
447 
448 	scatter_node_data();
449 
450 #ifdef CONFIG_SMP
451 	/* Set the node_data pointer for each per-cpu struct */
452 	for_each_possible_early_cpu(cpu) {
453 		node = node_cpuid[cpu].nid;
454 		per_cpu(ia64_cpu_info, cpu).node_data =
455 			mem_data[node].node_data;
456 	}
457 #else
458 	{
459 		struct cpuinfo_ia64 *cpu0_cpu_info;
460 		cpu = 0;
461 		node = node_cpuid[cpu].nid;
462 		cpu0_cpu_info = (struct cpuinfo_ia64 *)(__phys_per_cpu_start +
463 			((char *)&ia64_cpu_info - __per_cpu_start));
464 		cpu0_cpu_info->node_data = mem_data[node].node_data;
465 	}
466 #endif /* CONFIG_SMP */
467 }
468 
469 /**
470  * memory_less_node_alloc - * attempt to allocate memory on the best NUMA slit
471  * 	node but fall back to any other node when __alloc_bootmem_node fails
472  *	for best.
473  * @nid: node id
474  * @pernodesize: size of this node's pernode data
475  */
476 static void __init *memory_less_node_alloc(int nid, unsigned long pernodesize)
477 {
478 	void *ptr = NULL;
479 	u8 best = 0xff;
480 	int bestnode = -1, node, anynode = 0;
481 
482 	for_each_online_node(node) {
483 		if (node_isset(node, memory_less_mask))
484 			continue;
485 		else if (node_distance(nid, node) < best) {
486 			best = node_distance(nid, node);
487 			bestnode = node;
488 		}
489 		anynode = node;
490 	}
491 
492 	if (bestnode == -1)
493 		bestnode = anynode;
494 
495 	ptr = __alloc_bootmem_node(pgdat_list[bestnode], pernodesize,
496 		PERCPU_PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
497 
498 	return ptr;
499 }
500 
501 /**
502  * memory_less_nodes - allocate and initialize CPU only nodes pernode
503  *	information.
504  */
505 static void __init memory_less_nodes(void)
506 {
507 	unsigned long pernodesize;
508 	void *pernode;
509 	int node;
510 
511 	for_each_node_mask(node, memory_less_mask) {
512 		pernodesize = compute_pernodesize(node);
513 		pernode = memory_less_node_alloc(node, pernodesize);
514 		fill_pernode(node, __pa(pernode), pernodesize);
515 	}
516 
517 	return;
518 }
519 
520 /**
521  * find_memory - walk the EFI memory map and setup the bootmem allocator
522  *
523  * Called early in boot to setup the bootmem allocator, and to
524  * allocate the per-cpu and per-node structures.
525  */
526 void __init find_memory(void)
527 {
528 	int node;
529 
530 	reserve_memory();
531 
532 	if (num_online_nodes() == 0) {
533 		printk(KERN_ERR "node info missing!\n");
534 		node_set_online(0);
535 	}
536 
537 	nodes_or(memory_less_mask, memory_less_mask, node_online_map);
538 	min_low_pfn = -1;
539 	max_low_pfn = 0;
540 
541 	/* These actually end up getting called by call_pernode_memory() */
542 	efi_memmap_walk(filter_rsvd_memory, build_node_maps);
543 	efi_memmap_walk(filter_rsvd_memory, find_pernode_space);
544 	efi_memmap_walk(find_max_min_low_pfn, NULL);
545 
546 	for_each_online_node(node)
547 		if (bootmem_node_data[node].node_low_pfn) {
548 			node_clear(node, memory_less_mask);
549 			mem_data[node].min_pfn = ~0UL;
550 		}
551 
552 	efi_memmap_walk(filter_memory, register_active_ranges);
553 
554 	/*
555 	 * Initialize the boot memory maps in reverse order since that's
556 	 * what the bootmem allocator expects
557 	 */
558 	for (node = MAX_NUMNODES - 1; node >= 0; node--) {
559 		unsigned long pernode, pernodesize, map;
560 		struct bootmem_data *bdp;
561 
562 		if (!node_online(node))
563 			continue;
564 		else if (node_isset(node, memory_less_mask))
565 			continue;
566 
567 		bdp = &bootmem_node_data[node];
568 		pernode = mem_data[node].pernode_addr;
569 		pernodesize = mem_data[node].pernode_size;
570 		map = pernode + pernodesize;
571 
572 		init_bootmem_node(pgdat_list[node],
573 				  map>>PAGE_SHIFT,
574 				  bdp->node_min_pfn,
575 				  bdp->node_low_pfn);
576 	}
577 
578 	efi_memmap_walk(filter_rsvd_memory, free_node_bootmem);
579 
580 	reserve_pernode_space();
581 	memory_less_nodes();
582 	initialize_pernode_data();
583 
584 	max_pfn = max_low_pfn;
585 
586 	find_initrd();
587 }
588 
589 #ifdef CONFIG_SMP
590 /**
591  * per_cpu_init - setup per-cpu variables
592  *
593  * find_pernode_space() does most of this already, we just need to set
594  * local_per_cpu_offset
595  */
596 void *per_cpu_init(void)
597 {
598 	int cpu;
599 	static int first_time = 1;
600 
601 	if (first_time) {
602 		first_time = 0;
603 		for_each_possible_early_cpu(cpu)
604 			per_cpu(local_per_cpu_offset, cpu) = __per_cpu_offset[cpu];
605 	}
606 
607 	return __per_cpu_start + __per_cpu_offset[smp_processor_id()];
608 }
609 #endif /* CONFIG_SMP */
610 
611 /**
612  * call_pernode_memory - use SRAT to call callback functions with node info
613  * @start: physical start of range
614  * @len: length of range
615  * @arg: function to call for each range
616  *
617  * efi_memmap_walk() knows nothing about layout of memory across nodes. Find
618  * out to which node a block of memory belongs.  Ignore memory that we cannot
619  * identify, and split blocks that run across multiple nodes.
620  *
621  * Take this opportunity to round the start address up and the end address
622  * down to page boundaries.
623  */
624 void call_pernode_memory(unsigned long start, unsigned long len, void *arg)
625 {
626 	unsigned long rs, re, end = start + len;
627 	void (*func)(unsigned long, unsigned long, int);
628 	int i;
629 
630 	start = PAGE_ALIGN(start);
631 	end &= PAGE_MASK;
632 	if (start >= end)
633 		return;
634 
635 	func = arg;
636 
637 	if (!num_node_memblks) {
638 		/* No SRAT table, so assume one node (node 0) */
639 		if (start < end)
640 			(*func)(start, end - start, 0);
641 		return;
642 	}
643 
644 	for (i = 0; i < num_node_memblks; i++) {
645 		rs = max(start, node_memblk[i].start_paddr);
646 		re = min(end, node_memblk[i].start_paddr +
647 			 node_memblk[i].size);
648 
649 		if (rs < re)
650 			(*func)(rs, re - rs, node_memblk[i].nid);
651 
652 		if (re == end)
653 			break;
654 	}
655 }
656 
657 /**
658  * count_node_pages - callback to build per-node memory info structures
659  * @start: physical start of range
660  * @len: length of range
661  * @node: node where this range resides
662  *
663  * Each node has it's own number of physical pages, DMAable pages, start, and
664  * end page frame number.  This routine will be called by call_pernode_memory()
665  * for each piece of usable memory and will setup these values for each node.
666  * Very similar to build_maps().
667  */
668 static __init int count_node_pages(unsigned long start, unsigned long len, int node)
669 {
670 	unsigned long end = start + len;
671 
672 #ifdef CONFIG_ZONE_DMA32
673 	if (start <= __pa(MAX_DMA_ADDRESS))
674 		mem_data[node].num_dma_physpages +=
675 			(min(end, __pa(MAX_DMA_ADDRESS)) - start) >>PAGE_SHIFT;
676 #endif
677 	start = GRANULEROUNDDOWN(start);
678 	end = GRANULEROUNDUP(end);
679 	mem_data[node].max_pfn = max(mem_data[node].max_pfn,
680 				     end >> PAGE_SHIFT);
681 	mem_data[node].min_pfn = min(mem_data[node].min_pfn,
682 				     start >> PAGE_SHIFT);
683 
684 	return 0;
685 }
686 
687 /**
688  * paging_init - setup page tables
689  *
690  * paging_init() sets up the page tables for each node of the system and frees
691  * the bootmem allocator memory for general use.
692  */
693 void __init paging_init(void)
694 {
695 	unsigned long max_dma;
696 	unsigned long pfn_offset = 0;
697 	unsigned long max_pfn = 0;
698 	int node;
699 	unsigned long max_zone_pfns[MAX_NR_ZONES];
700 
701 	max_dma = virt_to_phys((void *) MAX_DMA_ADDRESS) >> PAGE_SHIFT;
702 
703 	efi_memmap_walk(filter_rsvd_memory, count_node_pages);
704 
705 	sparse_memory_present_with_active_regions(MAX_NUMNODES);
706 	sparse_init();
707 
708 #ifdef CONFIG_VIRTUAL_MEM_MAP
709 	VMALLOC_END -= PAGE_ALIGN(ALIGN(max_low_pfn, MAX_ORDER_NR_PAGES) *
710 		sizeof(struct page));
711 	vmem_map = (struct page *) VMALLOC_END;
712 	efi_memmap_walk(create_mem_map_page_table, NULL);
713 	printk("Virtual mem_map starts at 0x%p\n", vmem_map);
714 #endif
715 
716 	for_each_online_node(node) {
717 		pfn_offset = mem_data[node].min_pfn;
718 
719 #ifdef CONFIG_VIRTUAL_MEM_MAP
720 		NODE_DATA(node)->node_mem_map = vmem_map + pfn_offset;
721 #endif
722 		if (mem_data[node].max_pfn > max_pfn)
723 			max_pfn = mem_data[node].max_pfn;
724 	}
725 
726 	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
727 #ifdef CONFIG_ZONE_DMA32
728 	max_zone_pfns[ZONE_DMA32] = max_dma;
729 #endif
730 	max_zone_pfns[ZONE_NORMAL] = max_pfn;
731 	free_area_init_nodes(max_zone_pfns);
732 
733 	zero_page_memmap_ptr = virt_to_page(ia64_imva(empty_zero_page));
734 }
735 
736 #ifdef CONFIG_MEMORY_HOTPLUG
737 pg_data_t *arch_alloc_nodedata(int nid)
738 {
739 	unsigned long size = compute_pernodesize(nid);
740 
741 	return kzalloc(size, GFP_KERNEL);
742 }
743 
744 void arch_free_nodedata(pg_data_t *pgdat)
745 {
746 	kfree(pgdat);
747 }
748 
749 void arch_refresh_nodedata(int update_node, pg_data_t *update_pgdat)
750 {
751 	pgdat_list[update_node] = update_pgdat;
752 	scatter_node_data();
753 }
754 #endif
755 
756 #ifdef CONFIG_SPARSEMEM_VMEMMAP
757 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
758 		struct vmem_altmap *altmap)
759 {
760 	return vmemmap_populate_basepages(start, end, node);
761 }
762 
763 void vmemmap_free(unsigned long start, unsigned long end,
764 		struct vmem_altmap *altmap)
765 {
766 }
767 #endif
768