Pull kmalloc into release branch
[pandora-kernel.git] / arch / parisc / mm / init.c
1 /*
2  *  linux/arch/parisc/mm/init.c
3  *
4  *  Copyright (C) 1995  Linus Torvalds
5  *  Copyright 1999 SuSE GmbH
6  *    changed by Philipp Rumpf
7  *  Copyright 1999 Philipp Rumpf (prumpf@tux.org)
8  *  Copyright 2004 Randolph Chung (tausq@debian.org)
9  *  Copyright 2006 Helge Deller (deller@gmx.de)
10  *
11  */
12
13
14 #include <linux/module.h>
15 #include <linux/mm.h>
16 #include <linux/bootmem.h>
17 #include <linux/delay.h>
18 #include <linux/init.h>
19 #include <linux/pci.h>          /* for hppa_dma_ops and pcxl_dma_ops */
20 #include <linux/initrd.h>
21 #include <linux/swap.h>
22 #include <linux/unistd.h>
23 #include <linux/nodemask.h>     /* for node_online_map */
24 #include <linux/pagemap.h>      /* for release_pages and page_cache_release */
25
26 #include <asm/pgalloc.h>
27 #include <asm/tlb.h>
28 #include <asm/pdc_chassis.h>
29 #include <asm/mmzone.h>
30
31 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
32
33 extern char _text;      /* start of kernel code, defined by linker */
34 extern int  data_start;
35 extern char _end;       /* end of BSS, defined by linker */
36 extern char __init_begin, __init_end;
37
38 #ifdef CONFIG_DISCONTIGMEM
39 struct node_map_data node_data[MAX_NUMNODES] __read_mostly;
40 bootmem_data_t bmem_data[MAX_NUMNODES] __read_mostly;
41 unsigned char pfnnid_map[PFNNID_MAP_MAX] __read_mostly;
42 #endif
43
44 static struct resource data_resource = {
45         .name   = "Kernel data",
46         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM,
47 };
48
49 static struct resource code_resource = {
50         .name   = "Kernel code",
51         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM,
52 };
53
54 static struct resource pdcdata_resource = {
55         .name   = "PDC data (Page Zero)",
56         .start  = 0,
57         .end    = 0x9ff,
58         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM,
59 };
60
61 static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __read_mostly;
62
63 /* The following array is initialized from the firmware specific
64  * information retrieved in kernel/inventory.c.
65  */
66
67 physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __read_mostly;
68 int npmem_ranges __read_mostly;
69
70 #ifdef __LP64__
71 #define MAX_MEM         (~0UL)
72 #else /* !__LP64__ */
73 #define MAX_MEM         (3584U*1024U*1024U)
74 #endif /* !__LP64__ */
75
76 static unsigned long mem_limit __read_mostly = MAX_MEM;
77
78 static void __init mem_limit_func(void)
79 {
80         char *cp, *end;
81         unsigned long limit;
82         extern char saved_command_line[];
83
84         /* We need this before __setup() functions are called */
85
86         limit = MAX_MEM;
87         for (cp = saved_command_line; *cp; ) {
88                 if (memcmp(cp, "mem=", 4) == 0) {
89                         cp += 4;
90                         limit = memparse(cp, &end);
91                         if (end != cp)
92                                 break;
93                         cp = end;
94                 } else {
95                         while (*cp != ' ' && *cp)
96                                 ++cp;
97                         while (*cp == ' ')
98                                 ++cp;
99                 }
100         }
101
102         if (limit < mem_limit)
103                 mem_limit = limit;
104 }
105
106 #define MAX_GAP (0x40000000UL >> PAGE_SHIFT)
107
108 static void __init setup_bootmem(void)
109 {
110         unsigned long bootmap_size;
111         unsigned long mem_max;
112         unsigned long bootmap_pages;
113         unsigned long bootmap_start_pfn;
114         unsigned long bootmap_pfn;
115 #ifndef CONFIG_DISCONTIGMEM
116         physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1];
117         int npmem_holes;
118 #endif
119         int i, sysram_resource_count;
120
121         disable_sr_hashing(); /* Turn off space register hashing */
122
123         /*
124          * Sort the ranges. Since the number of ranges is typically
125          * small, and performance is not an issue here, just do
126          * a simple insertion sort.
127          */
128
129         for (i = 1; i < npmem_ranges; i++) {
130                 int j;
131
132                 for (j = i; j > 0; j--) {
133                         unsigned long tmp;
134
135                         if (pmem_ranges[j-1].start_pfn <
136                             pmem_ranges[j].start_pfn) {
137
138                                 break;
139                         }
140                         tmp = pmem_ranges[j-1].start_pfn;
141                         pmem_ranges[j-1].start_pfn = pmem_ranges[j].start_pfn;
142                         pmem_ranges[j].start_pfn = tmp;
143                         tmp = pmem_ranges[j-1].pages;
144                         pmem_ranges[j-1].pages = pmem_ranges[j].pages;
145                         pmem_ranges[j].pages = tmp;
146                 }
147         }
148
149 #ifndef CONFIG_DISCONTIGMEM
150         /*
151          * Throw out ranges that are too far apart (controlled by
152          * MAX_GAP).
153          */
154
155         for (i = 1; i < npmem_ranges; i++) {
156                 if (pmem_ranges[i].start_pfn -
157                         (pmem_ranges[i-1].start_pfn +
158                          pmem_ranges[i-1].pages) > MAX_GAP) {
159                         npmem_ranges = i;
160                         printk("Large gap in memory detected (%ld pages). "
161                                "Consider turning on CONFIG_DISCONTIGMEM\n",
162                                pmem_ranges[i].start_pfn -
163                                (pmem_ranges[i-1].start_pfn +
164                                 pmem_ranges[i-1].pages));
165                         break;
166                 }
167         }
168 #endif
169
170         if (npmem_ranges > 1) {
171
172                 /* Print the memory ranges */
173
174                 printk(KERN_INFO "Memory Ranges:\n");
175
176                 for (i = 0; i < npmem_ranges; i++) {
177                         unsigned long start;
178                         unsigned long size;
179
180                         size = (pmem_ranges[i].pages << PAGE_SHIFT);
181                         start = (pmem_ranges[i].start_pfn << PAGE_SHIFT);
182                         printk(KERN_INFO "%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n",
183                                 i,start, start + (size - 1), size >> 20);
184                 }
185         }
186
187         sysram_resource_count = npmem_ranges;
188         for (i = 0; i < sysram_resource_count; i++) {
189                 struct resource *res = &sysram_resources[i];
190                 res->name = "System RAM";
191                 res->start = pmem_ranges[i].start_pfn << PAGE_SHIFT;
192                 res->end = res->start + (pmem_ranges[i].pages << PAGE_SHIFT)-1;
193                 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
194                 request_resource(&iomem_resource, res);
195         }
196
197         /*
198          * For 32 bit kernels we limit the amount of memory we can
199          * support, in order to preserve enough kernel address space
200          * for other purposes. For 64 bit kernels we don't normally
201          * limit the memory, but this mechanism can be used to
202          * artificially limit the amount of memory (and it is written
203          * to work with multiple memory ranges).
204          */
205
206         mem_limit_func();       /* check for "mem=" argument */
207
208         mem_max = 0;
209         num_physpages = 0;
210         for (i = 0; i < npmem_ranges; i++) {
211                 unsigned long rsize;
212
213                 rsize = pmem_ranges[i].pages << PAGE_SHIFT;
214                 if ((mem_max + rsize) > mem_limit) {
215                         printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20);
216                         if (mem_max == mem_limit)
217                                 npmem_ranges = i;
218                         else {
219                                 pmem_ranges[i].pages =   (mem_limit >> PAGE_SHIFT)
220                                                        - (mem_max >> PAGE_SHIFT);
221                                 npmem_ranges = i + 1;
222                                 mem_max = mem_limit;
223                         }
224                 num_physpages += pmem_ranges[i].pages;
225                         break;
226                 }
227             num_physpages += pmem_ranges[i].pages;
228                 mem_max += rsize;
229         }
230
231         printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20);
232
233 #ifndef CONFIG_DISCONTIGMEM
234         /* Merge the ranges, keeping track of the holes */
235
236         {
237                 unsigned long end_pfn;
238                 unsigned long hole_pages;
239
240                 npmem_holes = 0;
241                 end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages;
242                 for (i = 1; i < npmem_ranges; i++) {
243
244                         hole_pages = pmem_ranges[i].start_pfn - end_pfn;
245                         if (hole_pages) {
246                                 pmem_holes[npmem_holes].start_pfn = end_pfn;
247                                 pmem_holes[npmem_holes++].pages = hole_pages;
248                                 end_pfn += hole_pages;
249                         }
250                         end_pfn += pmem_ranges[i].pages;
251                 }
252
253                 pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn;
254                 npmem_ranges = 1;
255         }
256 #endif
257
258         bootmap_pages = 0;
259         for (i = 0; i < npmem_ranges; i++)
260                 bootmap_pages += bootmem_bootmap_pages(pmem_ranges[i].pages);
261
262         bootmap_start_pfn = PAGE_ALIGN(__pa((unsigned long) &_end)) >> PAGE_SHIFT;
263
264 #ifdef CONFIG_DISCONTIGMEM
265         for (i = 0; i < MAX_PHYSMEM_RANGES; i++) {
266                 memset(NODE_DATA(i), 0, sizeof(pg_data_t));
267                 NODE_DATA(i)->bdata = &bmem_data[i];
268         }
269         memset(pfnnid_map, 0xff, sizeof(pfnnid_map));
270
271         for (i = 0; i < npmem_ranges; i++)
272                 node_set_online(i);
273 #endif
274
275         /*
276          * Initialize and free the full range of memory in each range.
277          * Note that the only writing these routines do are to the bootmap,
278          * and we've made sure to locate the bootmap properly so that they
279          * won't be writing over anything important.
280          */
281
282         bootmap_pfn = bootmap_start_pfn;
283         max_pfn = 0;
284         for (i = 0; i < npmem_ranges; i++) {
285                 unsigned long start_pfn;
286                 unsigned long npages;
287
288                 start_pfn = pmem_ranges[i].start_pfn;
289                 npages = pmem_ranges[i].pages;
290
291                 bootmap_size = init_bootmem_node(NODE_DATA(i),
292                                                 bootmap_pfn,
293                                                 start_pfn,
294                                                 (start_pfn + npages) );
295                 free_bootmem_node(NODE_DATA(i),
296                                   (start_pfn << PAGE_SHIFT),
297                                   (npages << PAGE_SHIFT) );
298                 bootmap_pfn += (bootmap_size + PAGE_SIZE - 1) >> PAGE_SHIFT;
299                 if ((start_pfn + npages) > max_pfn)
300                         max_pfn = start_pfn + npages;
301         }
302
303         /* IOMMU is always used to access "high mem" on those boxes
304          * that can support enough mem that a PCI device couldn't
305          * directly DMA to any physical addresses.
306          * ISA DMA support will need to revisit this.
307          */
308         max_low_pfn = max_pfn;
309
310         if ((bootmap_pfn - bootmap_start_pfn) != bootmap_pages) {
311                 printk(KERN_WARNING "WARNING! bootmap sizing is messed up!\n");
312                 BUG();
313         }
314
315         /* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */
316
317 #define PDC_CONSOLE_IO_IODC_SIZE 32768
318
319         reserve_bootmem_node(NODE_DATA(0), 0UL,
320                         (unsigned long)(PAGE0->mem_free + PDC_CONSOLE_IO_IODC_SIZE));
321         reserve_bootmem_node(NODE_DATA(0),__pa((unsigned long)&_text),
322                         (unsigned long)(&_end - &_text));
323         reserve_bootmem_node(NODE_DATA(0), (bootmap_start_pfn << PAGE_SHIFT),
324                         ((bootmap_pfn - bootmap_start_pfn) << PAGE_SHIFT));
325
326 #ifndef CONFIG_DISCONTIGMEM
327
328         /* reserve the holes */
329
330         for (i = 0; i < npmem_holes; i++) {
331                 reserve_bootmem_node(NODE_DATA(0),
332                                 (pmem_holes[i].start_pfn << PAGE_SHIFT),
333                                 (pmem_holes[i].pages << PAGE_SHIFT));
334         }
335 #endif
336
337 #ifdef CONFIG_BLK_DEV_INITRD
338         if (initrd_start) {
339                 printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end);
340                 if (__pa(initrd_start) < mem_max) {
341                         unsigned long initrd_reserve;
342
343                         if (__pa(initrd_end) > mem_max) {
344                                 initrd_reserve = mem_max - __pa(initrd_start);
345                         } else {
346                                 initrd_reserve = initrd_end - initrd_start;
347                         }
348                         initrd_below_start_ok = 1;
349                         printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max);
350
351                         reserve_bootmem_node(NODE_DATA(0),__pa(initrd_start), initrd_reserve);
352                 }
353         }
354 #endif
355
356         data_resource.start =  virt_to_phys(&data_start);
357         data_resource.end = virt_to_phys(&_end)-1;
358         code_resource.start = virt_to_phys(&_text);
359         code_resource.end = virt_to_phys(&data_start)-1;
360
361         /* We don't know which region the kernel will be in, so try
362          * all of them.
363          */
364         for (i = 0; i < sysram_resource_count; i++) {
365                 struct resource *res = &sysram_resources[i];
366                 request_resource(res, &code_resource);
367                 request_resource(res, &data_resource);
368         }
369         request_resource(&sysram_resources[0], &pdcdata_resource);
370 }
371
372 void free_initmem(void)
373 {
374         unsigned long addr, init_begin, init_end;
375
376         printk(KERN_INFO "Freeing unused kernel memory: ");
377
378 #ifdef CONFIG_DEBUG_KERNEL
379         /* Attempt to catch anyone trying to execute code here
380          * by filling the page with BRK insns.
381          * 
382          * If we disable interrupts for all CPUs, then IPI stops working.
383          * Kinda breaks the global cache flushing.
384          */
385         local_irq_disable();
386
387         memset(&__init_begin, 0x00, 
388                 (unsigned long)&__init_end - (unsigned long)&__init_begin);
389
390         flush_data_cache();
391         asm volatile("sync" : : );
392         flush_icache_range((unsigned long)&__init_begin, (unsigned long)&__init_end);
393         asm volatile("sync" : : );
394
395         local_irq_enable();
396 #endif
397         
398         /* align __init_begin and __init_end to page size,
399            ignoring linker script where we might have tried to save RAM */
400         init_begin = PAGE_ALIGN((unsigned long)(&__init_begin));
401         init_end   = PAGE_ALIGN((unsigned long)(&__init_end));
402         for (addr = init_begin; addr < init_end; addr += PAGE_SIZE) {
403                 ClearPageReserved(virt_to_page(addr));
404                 init_page_count(virt_to_page(addr));
405                 free_page(addr);
406                 num_physpages++;
407                 totalram_pages++;
408         }
409
410         /* set up a new led state on systems shipped LED State panel */
411         pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE);
412         
413         printk("%luk freed\n", (init_end - init_begin) >> 10);
414 }
415
416
417 #ifdef CONFIG_DEBUG_RODATA
418 void mark_rodata_ro(void)
419 {
420         extern char __start_rodata, __end_rodata;
421         /* rodata memory was already mapped with KERNEL_RO access rights by
422            pagetable_init() and map_pages(). No need to do additional stuff here */
423         printk (KERN_INFO "Write protecting the kernel read-only data: %luk\n",
424                 (unsigned long)(&__end_rodata - &__start_rodata) >> 10);
425 }
426 #endif
427
428
429 /*
430  * Just an arbitrary offset to serve as a "hole" between mapping areas
431  * (between top of physical memory and a potential pcxl dma mapping
432  * area, and below the vmalloc mapping area).
433  *
434  * The current 32K value just means that there will be a 32K "hole"
435  * between mapping areas. That means that  any out-of-bounds memory
436  * accesses will hopefully be caught. The vmalloc() routines leaves
437  * a hole of 4kB between each vmalloced area for the same reason.
438  */
439
440  /* Leave room for gateway page expansion */
441 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE
442 #error KERNEL_MAP_START is in gateway reserved region
443 #endif
444 #define MAP_START (KERNEL_MAP_START)
445
446 #define VM_MAP_OFFSET  (32*1024)
447 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
448                                      & ~(VM_MAP_OFFSET-1)))
449
450 void *vmalloc_start __read_mostly;
451 EXPORT_SYMBOL(vmalloc_start);
452
453 #ifdef CONFIG_PA11
454 unsigned long pcxl_dma_start __read_mostly;
455 #endif
456
457 void __init mem_init(void)
458 {
459         high_memory = __va((max_pfn << PAGE_SHIFT));
460
461 #ifndef CONFIG_DISCONTIGMEM
462         max_mapnr = page_to_pfn(virt_to_page(high_memory - 1)) + 1;
463         totalram_pages += free_all_bootmem();
464 #else
465         {
466                 int i;
467
468                 for (i = 0; i < npmem_ranges; i++)
469                         totalram_pages += free_all_bootmem_node(NODE_DATA(i));
470         }
471 #endif
472
473         printk(KERN_INFO "Memory: %luk available\n", num_physpages << (PAGE_SHIFT-10));
474
475 #ifdef CONFIG_PA11
476         if (hppa_dma_ops == &pcxl_dma_ops) {
477                 pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START);
478                 vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start + PCXL_DMA_MAP_SIZE);
479         } else {
480                 pcxl_dma_start = 0;
481                 vmalloc_start = SET_MAP_OFFSET(MAP_START);
482         }
483 #else
484         vmalloc_start = SET_MAP_OFFSET(MAP_START);
485 #endif
486
487 }
488
489 unsigned long *empty_zero_page __read_mostly;
490
491 void show_mem(void)
492 {
493         int i,free = 0,total = 0,reserved = 0;
494         int shared = 0, cached = 0;
495
496         printk(KERN_INFO "Mem-info:\n");
497         show_free_areas();
498         printk(KERN_INFO "Free swap:     %6ldkB\n",
499                                 nr_swap_pages<<(PAGE_SHIFT-10));
500 #ifndef CONFIG_DISCONTIGMEM
501         i = max_mapnr;
502         while (i-- > 0) {
503                 total++;
504                 if (PageReserved(mem_map+i))
505                         reserved++;
506                 else if (PageSwapCache(mem_map+i))
507                         cached++;
508                 else if (!page_count(&mem_map[i]))
509                         free++;
510                 else
511                         shared += page_count(&mem_map[i]) - 1;
512         }
513 #else
514         for (i = 0; i < npmem_ranges; i++) {
515                 int j;
516
517                 for (j = node_start_pfn(i); j < node_end_pfn(i); j++) {
518                         struct page *p;
519                         unsigned long flags;
520
521                         pgdat_resize_lock(NODE_DATA(i), &flags);
522                         p = nid_page_nr(i, j) - node_start_pfn(i);
523
524                         total++;
525                         if (PageReserved(p))
526                                 reserved++;
527                         else if (PageSwapCache(p))
528                                 cached++;
529                         else if (!page_count(p))
530                                 free++;
531                         else
532                                 shared += page_count(p) - 1;
533                         pgdat_resize_unlock(NODE_DATA(i), &flags);
534                 }
535         }
536 #endif
537         printk(KERN_INFO "%d pages of RAM\n", total);
538         printk(KERN_INFO "%d reserved pages\n", reserved);
539         printk(KERN_INFO "%d pages shared\n", shared);
540         printk(KERN_INFO "%d pages swap cached\n", cached);
541
542
543 #ifdef CONFIG_DISCONTIGMEM
544         {
545                 struct zonelist *zl;
546                 int i, j, k;
547
548                 for (i = 0; i < npmem_ranges; i++) {
549                         for (j = 0; j < MAX_NR_ZONES; j++) {
550                                 zl = NODE_DATA(i)->node_zonelists + j;
551
552                                 printk("Zone list for zone %d on node %d: ", j, i);
553                                 for (k = 0; zl->zones[k] != NULL; k++) 
554                                         printk("[%d/%s] ", zl->zones[k]->zone_pgdat->node_id, zl->zones[k]->name);
555                                 printk("\n");
556                         }
557                 }
558         }
559 #endif
560 }
561
562
563 static void __init map_pages(unsigned long start_vaddr, unsigned long start_paddr, unsigned long size, pgprot_t pgprot)
564 {
565         pgd_t *pg_dir;
566         pmd_t *pmd;
567         pte_t *pg_table;
568         unsigned long end_paddr;
569         unsigned long start_pmd;
570         unsigned long start_pte;
571         unsigned long tmp1;
572         unsigned long tmp2;
573         unsigned long address;
574         unsigned long ro_start;
575         unsigned long ro_end;
576         unsigned long fv_addr;
577         unsigned long gw_addr;
578         extern const unsigned long fault_vector_20;
579         extern void * const linux_gateway_page;
580
581         ro_start = __pa((unsigned long)&_text);
582         ro_end   = __pa((unsigned long)&data_start);
583         fv_addr  = __pa((unsigned long)&fault_vector_20) & PAGE_MASK;
584         gw_addr  = __pa((unsigned long)&linux_gateway_page) & PAGE_MASK;
585
586         end_paddr = start_paddr + size;
587
588         pg_dir = pgd_offset_k(start_vaddr);
589
590 #if PTRS_PER_PMD == 1
591         start_pmd = 0;
592 #else
593         start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
594 #endif
595         start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
596
597         address = start_paddr;
598         while (address < end_paddr) {
599 #if PTRS_PER_PMD == 1
600                 pmd = (pmd_t *)__pa(pg_dir);
601 #else
602                 pmd = (pmd_t *)pgd_address(*pg_dir);
603
604                 /*
605                  * pmd is physical at this point
606                  */
607
608                 if (!pmd) {
609                         pmd = (pmd_t *) alloc_bootmem_low_pages_node(NODE_DATA(0),PAGE_SIZE << PMD_ORDER);
610                         pmd = (pmd_t *) __pa(pmd);
611                 }
612
613                 pgd_populate(NULL, pg_dir, __va(pmd));
614 #endif
615                 pg_dir++;
616
617                 /* now change pmd to kernel virtual addresses */
618
619                 pmd = (pmd_t *)__va(pmd) + start_pmd;
620                 for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++,pmd++) {
621
622                         /*
623                          * pg_table is physical at this point
624                          */
625
626                         pg_table = (pte_t *)pmd_address(*pmd);
627                         if (!pg_table) {
628                                 pg_table = (pte_t *)
629                                         alloc_bootmem_low_pages_node(NODE_DATA(0),PAGE_SIZE);
630                                 pg_table = (pte_t *) __pa(pg_table);
631                         }
632
633                         pmd_populate_kernel(NULL, pmd, __va(pg_table));
634
635                         /* now change pg_table to kernel virtual addresses */
636
637                         pg_table = (pte_t *) __va(pg_table) + start_pte;
638                         for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++,pg_table++) {
639                                 pte_t pte;
640
641                                 /*
642                                  * Map the fault vector writable so we can
643                                  * write the HPMC checksum.
644                                  */
645 #if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
646                                 if (address >= ro_start && address < ro_end
647                                                         && address != fv_addr
648                                                         && address != gw_addr)
649                                     pte = __mk_pte(address, PAGE_KERNEL_RO);
650                                 else
651 #endif
652                                     pte = __mk_pte(address, pgprot);
653
654                                 if (address >= end_paddr)
655                                         pte_val(pte) = 0;
656
657                                 set_pte(pg_table, pte);
658
659                                 address += PAGE_SIZE;
660                         }
661                         start_pte = 0;
662
663                         if (address >= end_paddr)
664                             break;
665                 }
666                 start_pmd = 0;
667         }
668 }
669
670 /*
671  * pagetable_init() sets up the page tables
672  *
673  * Note that gateway_init() places the Linux gateway page at page 0.
674  * Since gateway pages cannot be dereferenced this has the desirable
675  * side effect of trapping those pesky NULL-reference errors in the
676  * kernel.
677  */
678 static void __init pagetable_init(void)
679 {
680         int range;
681
682         /* Map each physical memory range to its kernel vaddr */
683
684         for (range = 0; range < npmem_ranges; range++) {
685                 unsigned long start_paddr;
686                 unsigned long end_paddr;
687                 unsigned long size;
688
689                 start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT;
690                 end_paddr = start_paddr + (pmem_ranges[range].pages << PAGE_SHIFT);
691                 size = pmem_ranges[range].pages << PAGE_SHIFT;
692
693                 map_pages((unsigned long)__va(start_paddr), start_paddr,
694                         size, PAGE_KERNEL);
695         }
696
697 #ifdef CONFIG_BLK_DEV_INITRD
698         if (initrd_end && initrd_end > mem_limit) {
699                 printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end);
700                 map_pages(initrd_start, __pa(initrd_start),
701                         initrd_end - initrd_start, PAGE_KERNEL);
702         }
703 #endif
704
705         empty_zero_page = alloc_bootmem_pages(PAGE_SIZE);
706         memset(empty_zero_page, 0, PAGE_SIZE);
707 }
708
709 static void __init gateway_init(void)
710 {
711         unsigned long linux_gateway_page_addr;
712         /* FIXME: This is 'const' in order to trick the compiler
713            into not treating it as DP-relative data. */
714         extern void * const linux_gateway_page;
715
716         linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
717
718         /*
719          * Setup Linux Gateway page.
720          *
721          * The Linux gateway page will reside in kernel space (on virtual
722          * page 0), so it doesn't need to be aliased into user space.
723          */
724
725         map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page),
726                 PAGE_SIZE, PAGE_GATEWAY);
727 }
728
729 #ifdef CONFIG_HPUX
730 void
731 map_hpux_gateway_page(struct task_struct *tsk, struct mm_struct *mm)
732 {
733         pgd_t *pg_dir;
734         pmd_t *pmd;
735         pte_t *pg_table;
736         unsigned long start_pmd;
737         unsigned long start_pte;
738         unsigned long address;
739         unsigned long hpux_gw_page_addr;
740         /* FIXME: This is 'const' in order to trick the compiler
741            into not treating it as DP-relative data. */
742         extern void * const hpux_gateway_page;
743
744         hpux_gw_page_addr = HPUX_GATEWAY_ADDR & PAGE_MASK;
745
746         /*
747          * Setup HP-UX Gateway page.
748          *
749          * The HP-UX gateway page resides in the user address space,
750          * so it needs to be aliased into each process.
751          */
752
753         pg_dir = pgd_offset(mm,hpux_gw_page_addr);
754
755 #if PTRS_PER_PMD == 1
756         start_pmd = 0;
757 #else
758         start_pmd = ((hpux_gw_page_addr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
759 #endif
760         start_pte = ((hpux_gw_page_addr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
761
762         address = __pa(&hpux_gateway_page);
763 #if PTRS_PER_PMD == 1
764         pmd = (pmd_t *)__pa(pg_dir);
765 #else
766         pmd = (pmd_t *) pgd_address(*pg_dir);
767
768         /*
769          * pmd is physical at this point
770          */
771
772         if (!pmd) {
773                 pmd = (pmd_t *) get_zeroed_page(GFP_KERNEL);
774                 pmd = (pmd_t *) __pa(pmd);
775         }
776
777         __pgd_val_set(*pg_dir, PxD_FLAG_PRESENT | PxD_FLAG_VALID | (unsigned long) pmd);
778 #endif
779         /* now change pmd to kernel virtual addresses */
780
781         pmd = (pmd_t *)__va(pmd) + start_pmd;
782
783         /*
784          * pg_table is physical at this point
785          */
786
787         pg_table = (pte_t *) pmd_address(*pmd);
788         if (!pg_table)
789                 pg_table = (pte_t *) __pa(get_zeroed_page(GFP_KERNEL));
790
791         __pmd_val_set(*pmd, PxD_FLAG_PRESENT | PxD_FLAG_VALID | (unsigned long) pg_table);
792
793         /* now change pg_table to kernel virtual addresses */
794
795         pg_table = (pte_t *) __va(pg_table) + start_pte;
796         set_pte(pg_table, __mk_pte(address, PAGE_GATEWAY));
797 }
798 EXPORT_SYMBOL(map_hpux_gateway_page);
799 #endif
800
801 void __init paging_init(void)
802 {
803         int i;
804
805         setup_bootmem();
806         pagetable_init();
807         gateway_init();
808         flush_cache_all_local(); /* start with known state */
809         flush_tlb_all_local(NULL);
810
811         for (i = 0; i < npmem_ranges; i++) {
812                 unsigned long zones_size[MAX_NR_ZONES] = { 0, 0, 0 };
813
814                 /* We have an IOMMU, so all memory can go into a single
815                    ZONE_DMA zone. */
816                 zones_size[ZONE_DMA] = pmem_ranges[i].pages;
817
818 #ifdef CONFIG_DISCONTIGMEM
819                 /* Need to initialize the pfnnid_map before we can initialize
820                    the zone */
821                 {
822                     int j;
823                     for (j = (pmem_ranges[i].start_pfn >> PFNNID_SHIFT);
824                          j <= ((pmem_ranges[i].start_pfn + pmem_ranges[i].pages) >> PFNNID_SHIFT);
825                          j++) {
826                         pfnnid_map[j] = i;
827                     }
828                 }
829 #endif
830
831                 free_area_init_node(i, NODE_DATA(i), zones_size,
832                                 pmem_ranges[i].start_pfn, NULL);
833         }
834 }
835
836 #ifdef CONFIG_PA20
837
838 /*
839  * Currently, all PA20 chips have 18 bit protection id's, which is the
840  * limiting factor (space ids are 32 bits).
841  */
842
843 #define NR_SPACE_IDS 262144
844
845 #else
846
847 /*
848  * Currently we have a one-to-one relationship between space id's and
849  * protection id's. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only
850  * support 15 bit protection id's, so that is the limiting factor.
851  * PCXT' has 18 bit protection id's, but only 16 bit spaceids, so it's
852  * probably not worth the effort for a special case here.
853  */
854
855 #define NR_SPACE_IDS 32768
856
857 #endif  /* !CONFIG_PA20 */
858
859 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2)
860 #define SID_ARRAY_SIZE  (NR_SPACE_IDS / (8 * sizeof(long)))
861
862 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */
863 static unsigned long dirty_space_id[SID_ARRAY_SIZE];
864 static unsigned long space_id_index;
865 static unsigned long free_space_ids = NR_SPACE_IDS - 1;
866 static unsigned long dirty_space_ids = 0;
867
868 static DEFINE_SPINLOCK(sid_lock);
869
870 unsigned long alloc_sid(void)
871 {
872         unsigned long index;
873
874         spin_lock(&sid_lock);
875
876         if (free_space_ids == 0) {
877                 if (dirty_space_ids != 0) {
878                         spin_unlock(&sid_lock);
879                         flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
880                         spin_lock(&sid_lock);
881                 }
882                 BUG_ON(free_space_ids == 0);
883         }
884
885         free_space_ids--;
886
887         index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
888         space_id[index >> SHIFT_PER_LONG] |= (1L << (index & (BITS_PER_LONG - 1)));
889         space_id_index = index;
890
891         spin_unlock(&sid_lock);
892
893         return index << SPACEID_SHIFT;
894 }
895
896 void free_sid(unsigned long spaceid)
897 {
898         unsigned long index = spaceid >> SPACEID_SHIFT;
899         unsigned long *dirty_space_offset;
900
901         dirty_space_offset = dirty_space_id + (index >> SHIFT_PER_LONG);
902         index &= (BITS_PER_LONG - 1);
903
904         spin_lock(&sid_lock);
905
906         BUG_ON(*dirty_space_offset & (1L << index)); /* attempt to free space id twice */
907
908         *dirty_space_offset |= (1L << index);
909         dirty_space_ids++;
910
911         spin_unlock(&sid_lock);
912 }
913
914
915 #ifdef CONFIG_SMP
916 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array)
917 {
918         int i;
919
920         /* NOTE: sid_lock must be held upon entry */
921
922         *ndirtyptr = dirty_space_ids;
923         if (dirty_space_ids != 0) {
924             for (i = 0; i < SID_ARRAY_SIZE; i++) {
925                 dirty_array[i] = dirty_space_id[i];
926                 dirty_space_id[i] = 0;
927             }
928             dirty_space_ids = 0;
929         }
930
931         return;
932 }
933
934 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array)
935 {
936         int i;
937
938         /* NOTE: sid_lock must be held upon entry */
939
940         if (ndirty != 0) {
941                 for (i = 0; i < SID_ARRAY_SIZE; i++) {
942                         space_id[i] ^= dirty_array[i];
943                 }
944
945                 free_space_ids += ndirty;
946                 space_id_index = 0;
947         }
948 }
949
950 #else /* CONFIG_SMP */
951
952 static void recycle_sids(void)
953 {
954         int i;
955
956         /* NOTE: sid_lock must be held upon entry */
957
958         if (dirty_space_ids != 0) {
959                 for (i = 0; i < SID_ARRAY_SIZE; i++) {
960                         space_id[i] ^= dirty_space_id[i];
961                         dirty_space_id[i] = 0;
962                 }
963
964                 free_space_ids += dirty_space_ids;
965                 dirty_space_ids = 0;
966                 space_id_index = 0;
967         }
968 }
969 #endif
970
971 /*
972  * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is
973  * purged, we can safely reuse the space ids that were released but
974  * not flushed from the tlb.
975  */
976
977 #ifdef CONFIG_SMP
978
979 static unsigned long recycle_ndirty;
980 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
981 static unsigned int recycle_inuse;
982
983 void flush_tlb_all(void)
984 {
985         int do_recycle;
986
987         do_recycle = 0;
988         spin_lock(&sid_lock);
989         if (dirty_space_ids > RECYCLE_THRESHOLD) {
990             BUG_ON(recycle_inuse);  /* FIXME: Use a semaphore/wait queue here */
991             get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
992             recycle_inuse++;
993             do_recycle++;
994         }
995         spin_unlock(&sid_lock);
996         on_each_cpu(flush_tlb_all_local, NULL, 1, 1);
997         if (do_recycle) {
998             spin_lock(&sid_lock);
999             recycle_sids(recycle_ndirty,recycle_dirty_array);
1000             recycle_inuse = 0;
1001             spin_unlock(&sid_lock);
1002         }
1003 }
1004 #else
1005 void flush_tlb_all(void)
1006 {
1007         spin_lock(&sid_lock);
1008         flush_tlb_all_local(NULL);
1009         recycle_sids();
1010         spin_unlock(&sid_lock);
1011 }
1012 #endif
1013
1014 #ifdef CONFIG_BLK_DEV_INITRD
1015 void free_initrd_mem(unsigned long start, unsigned long end)
1016 {
1017         if (start >= end)
1018                 return;
1019         printk(KERN_INFO "Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
1020         for (; start < end; start += PAGE_SIZE) {
1021                 ClearPageReserved(virt_to_page(start));
1022                 init_page_count(virt_to_page(start));
1023                 free_page(start);
1024                 num_physpages++;
1025                 totalram_pages++;
1026         }
1027 }
1028 #endif