Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/agpgart
[sfrench/cifs-2.6.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  *
10  */
11
12 #include <linux/config.h>
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;
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         addr = (unsigned long)(&__init_begin);
399         for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
400                 ClearPageReserved(virt_to_page(addr));
401                 init_page_count(virt_to_page(addr));
402                 free_page(addr);
403                 num_physpages++;
404                 totalram_pages++;
405         }
406
407         /* set up a new led state on systems shipped LED State panel */
408         pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE);
409         
410         printk("%luk freed\n", (unsigned long)(&__init_end - &__init_begin) >> 10);
411 }
412
413
414 #ifdef CONFIG_DEBUG_RODATA
415 void mark_rodata_ro(void)
416 {
417         extern char __start_rodata, __end_rodata;
418         /* rodata memory was already mapped with KERNEL_RO access rights by
419            pagetable_init() and map_pages(). No need to do additional stuff here */
420         printk (KERN_INFO "Write protecting the kernel read-only data: %luk\n",
421                 (unsigned long)(&__end_rodata - &__start_rodata) >> 10);
422 }
423 #endif
424
425
426 /*
427  * Just an arbitrary offset to serve as a "hole" between mapping areas
428  * (between top of physical memory and a potential pcxl dma mapping
429  * area, and below the vmalloc mapping area).
430  *
431  * The current 32K value just means that there will be a 32K "hole"
432  * between mapping areas. That means that  any out-of-bounds memory
433  * accesses will hopefully be caught. The vmalloc() routines leaves
434  * a hole of 4kB between each vmalloced area for the same reason.
435  */
436
437  /* Leave room for gateway page expansion */
438 #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE
439 #error KERNEL_MAP_START is in gateway reserved region
440 #endif
441 #define MAP_START (KERNEL_MAP_START)
442
443 #define VM_MAP_OFFSET  (32*1024)
444 #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
445                                      & ~(VM_MAP_OFFSET-1)))
446
447 void *vmalloc_start __read_mostly;
448 EXPORT_SYMBOL(vmalloc_start);
449
450 #ifdef CONFIG_PA11
451 unsigned long pcxl_dma_start __read_mostly;
452 #endif
453
454 void __init mem_init(void)
455 {
456         high_memory = __va((max_pfn << PAGE_SHIFT));
457
458 #ifndef CONFIG_DISCONTIGMEM
459         max_mapnr = page_to_pfn(virt_to_page(high_memory - 1)) + 1;
460         totalram_pages += free_all_bootmem();
461 #else
462         {
463                 int i;
464
465                 for (i = 0; i < npmem_ranges; i++)
466                         totalram_pages += free_all_bootmem_node(NODE_DATA(i));
467         }
468 #endif
469
470         printk(KERN_INFO "Memory: %luk available\n", num_physpages << (PAGE_SHIFT-10));
471
472 #ifdef CONFIG_PA11
473         if (hppa_dma_ops == &pcxl_dma_ops) {
474                 pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START);
475                 vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start + PCXL_DMA_MAP_SIZE);
476         } else {
477                 pcxl_dma_start = 0;
478                 vmalloc_start = SET_MAP_OFFSET(MAP_START);
479         }
480 #else
481         vmalloc_start = SET_MAP_OFFSET(MAP_START);
482 #endif
483
484 }
485
486 unsigned long *empty_zero_page __read_mostly;
487
488 void show_mem(void)
489 {
490         int i,free = 0,total = 0,reserved = 0;
491         int shared = 0, cached = 0;
492
493         printk(KERN_INFO "Mem-info:\n");
494         show_free_areas();
495         printk(KERN_INFO "Free swap:     %6ldkB\n",
496                                 nr_swap_pages<<(PAGE_SHIFT-10));
497 #ifndef CONFIG_DISCONTIGMEM
498         i = max_mapnr;
499         while (i-- > 0) {
500                 total++;
501                 if (PageReserved(mem_map+i))
502                         reserved++;
503                 else if (PageSwapCache(mem_map+i))
504                         cached++;
505                 else if (!page_count(&mem_map[i]))
506                         free++;
507                 else
508                         shared += page_count(&mem_map[i]) - 1;
509         }
510 #else
511         for (i = 0; i < npmem_ranges; i++) {
512                 int j;
513
514                 for (j = node_start_pfn(i); j < node_end_pfn(i); j++) {
515                         struct page *p;
516                         unsigned long flags;
517
518                         pgdat_resize_lock(NODE_DATA(i), &flags);
519                         p = nid_page_nr(i, j) - node_start_pfn(i);
520
521                         total++;
522                         if (PageReserved(p))
523                                 reserved++;
524                         else if (PageSwapCache(p))
525                                 cached++;
526                         else if (!page_count(p))
527                                 free++;
528                         else
529                                 shared += page_count(p) - 1;
530                         pgdat_resize_unlock(NODE_DATA(i), &flags);
531                 }
532         }
533 #endif
534         printk(KERN_INFO "%d pages of RAM\n", total);
535         printk(KERN_INFO "%d reserved pages\n", reserved);
536         printk(KERN_INFO "%d pages shared\n", shared);
537         printk(KERN_INFO "%d pages swap cached\n", cached);
538
539
540 #ifdef CONFIG_DISCONTIGMEM
541         {
542                 struct zonelist *zl;
543                 int i, j, k;
544
545                 for (i = 0; i < npmem_ranges; i++) {
546                         for (j = 0; j < MAX_NR_ZONES; j++) {
547                                 zl = NODE_DATA(i)->node_zonelists + j;
548
549                                 printk("Zone list for zone %d on node %d: ", j, i);
550                                 for (k = 0; zl->zones[k] != NULL; k++) 
551                                         printk("[%d/%s] ", zl->zones[k]->zone_pgdat->node_id, zl->zones[k]->name);
552                                 printk("\n");
553                         }
554                 }
555         }
556 #endif
557 }
558
559
560 static void __init map_pages(unsigned long start_vaddr, unsigned long start_paddr, unsigned long size, pgprot_t pgprot)
561 {
562         pgd_t *pg_dir;
563         pmd_t *pmd;
564         pte_t *pg_table;
565         unsigned long end_paddr;
566         unsigned long start_pmd;
567         unsigned long start_pte;
568         unsigned long tmp1;
569         unsigned long tmp2;
570         unsigned long address;
571         unsigned long ro_start;
572         unsigned long ro_end;
573         unsigned long fv_addr;
574         unsigned long gw_addr;
575         extern const unsigned long fault_vector_20;
576         extern void * const linux_gateway_page;
577
578         ro_start = __pa((unsigned long)&_text);
579         ro_end   = __pa((unsigned long)&data_start);
580         fv_addr  = __pa((unsigned long)&fault_vector_20) & PAGE_MASK;
581         gw_addr  = __pa((unsigned long)&linux_gateway_page) & PAGE_MASK;
582
583         end_paddr = start_paddr + size;
584
585         pg_dir = pgd_offset_k(start_vaddr);
586
587 #if PTRS_PER_PMD == 1
588         start_pmd = 0;
589 #else
590         start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
591 #endif
592         start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
593
594         address = start_paddr;
595         while (address < end_paddr) {
596 #if PTRS_PER_PMD == 1
597                 pmd = (pmd_t *)__pa(pg_dir);
598 #else
599                 pmd = (pmd_t *)pgd_address(*pg_dir);
600
601                 /*
602                  * pmd is physical at this point
603                  */
604
605                 if (!pmd) {
606                         pmd = (pmd_t *) alloc_bootmem_low_pages_node(NODE_DATA(0),PAGE_SIZE << PMD_ORDER);
607                         pmd = (pmd_t *) __pa(pmd);
608                 }
609
610                 pgd_populate(NULL, pg_dir, __va(pmd));
611 #endif
612                 pg_dir++;
613
614                 /* now change pmd to kernel virtual addresses */
615
616                 pmd = (pmd_t *)__va(pmd) + start_pmd;
617                 for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++,pmd++) {
618
619                         /*
620                          * pg_table is physical at this point
621                          */
622
623                         pg_table = (pte_t *)pmd_address(*pmd);
624                         if (!pg_table) {
625                                 pg_table = (pte_t *)
626                                         alloc_bootmem_low_pages_node(NODE_DATA(0),PAGE_SIZE);
627                                 pg_table = (pte_t *) __pa(pg_table);
628                         }
629
630                         pmd_populate_kernel(NULL, pmd, __va(pg_table));
631
632                         /* now change pg_table to kernel virtual addresses */
633
634                         pg_table = (pte_t *) __va(pg_table) + start_pte;
635                         for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++,pg_table++) {
636                                 pte_t pte;
637
638                                 /*
639                                  * Map the fault vector writable so we can
640                                  * write the HPMC checksum.
641                                  */
642                                 if (address >= ro_start && address < ro_end
643                                                         && address != fv_addr
644                                                         && address != gw_addr)
645                                     pte = __mk_pte(address, PAGE_KERNEL_RO);
646                                 else
647                                     pte = __mk_pte(address, pgprot);
648
649                                 if (address >= end_paddr)
650                                         pte_val(pte) = 0;
651
652                                 set_pte(pg_table, pte);
653
654                                 address += PAGE_SIZE;
655                         }
656                         start_pte = 0;
657
658                         if (address >= end_paddr)
659                             break;
660                 }
661                 start_pmd = 0;
662         }
663 }
664
665 /*
666  * pagetable_init() sets up the page tables
667  *
668  * Note that gateway_init() places the Linux gateway page at page 0.
669  * Since gateway pages cannot be dereferenced this has the desirable
670  * side effect of trapping those pesky NULL-reference errors in the
671  * kernel.
672  */
673 static void __init pagetable_init(void)
674 {
675         int range;
676
677         /* Map each physical memory range to its kernel vaddr */
678
679         for (range = 0; range < npmem_ranges; range++) {
680                 unsigned long start_paddr;
681                 unsigned long end_paddr;
682                 unsigned long size;
683
684                 start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT;
685                 end_paddr = start_paddr + (pmem_ranges[range].pages << PAGE_SHIFT);
686                 size = pmem_ranges[range].pages << PAGE_SHIFT;
687
688                 map_pages((unsigned long)__va(start_paddr), start_paddr,
689                         size, PAGE_KERNEL);
690         }
691
692 #ifdef CONFIG_BLK_DEV_INITRD
693         if (initrd_end && initrd_end > mem_limit) {
694                 printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end);
695                 map_pages(initrd_start, __pa(initrd_start),
696                         initrd_end - initrd_start, PAGE_KERNEL);
697         }
698 #endif
699
700         empty_zero_page = alloc_bootmem_pages(PAGE_SIZE);
701         memset(empty_zero_page, 0, PAGE_SIZE);
702 }
703
704 static void __init gateway_init(void)
705 {
706         unsigned long linux_gateway_page_addr;
707         /* FIXME: This is 'const' in order to trick the compiler
708            into not treating it as DP-relative data. */
709         extern void * const linux_gateway_page;
710
711         linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
712
713         /*
714          * Setup Linux Gateway page.
715          *
716          * The Linux gateway page will reside in kernel space (on virtual
717          * page 0), so it doesn't need to be aliased into user space.
718          */
719
720         map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page),
721                 PAGE_SIZE, PAGE_GATEWAY);
722 }
723
724 #ifdef CONFIG_HPUX
725 void
726 map_hpux_gateway_page(struct task_struct *tsk, struct mm_struct *mm)
727 {
728         pgd_t *pg_dir;
729         pmd_t *pmd;
730         pte_t *pg_table;
731         unsigned long start_pmd;
732         unsigned long start_pte;
733         unsigned long address;
734         unsigned long hpux_gw_page_addr;
735         /* FIXME: This is 'const' in order to trick the compiler
736            into not treating it as DP-relative data. */
737         extern void * const hpux_gateway_page;
738
739         hpux_gw_page_addr = HPUX_GATEWAY_ADDR & PAGE_MASK;
740
741         /*
742          * Setup HP-UX Gateway page.
743          *
744          * The HP-UX gateway page resides in the user address space,
745          * so it needs to be aliased into each process.
746          */
747
748         pg_dir = pgd_offset(mm,hpux_gw_page_addr);
749
750 #if PTRS_PER_PMD == 1
751         start_pmd = 0;
752 #else
753         start_pmd = ((hpux_gw_page_addr >> PMD_SHIFT) & (PTRS_PER_PMD - 1));
754 #endif
755         start_pte = ((hpux_gw_page_addr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
756
757         address = __pa(&hpux_gateway_page);
758 #if PTRS_PER_PMD == 1
759         pmd = (pmd_t *)__pa(pg_dir);
760 #else
761         pmd = (pmd_t *) pgd_address(*pg_dir);
762
763         /*
764          * pmd is physical at this point
765          */
766
767         if (!pmd) {
768                 pmd = (pmd_t *) get_zeroed_page(GFP_KERNEL);
769                 pmd = (pmd_t *) __pa(pmd);
770         }
771
772         __pgd_val_set(*pg_dir, PxD_FLAG_PRESENT | PxD_FLAG_VALID | (unsigned long) pmd);
773 #endif
774         /* now change pmd to kernel virtual addresses */
775
776         pmd = (pmd_t *)__va(pmd) + start_pmd;
777
778         /*
779          * pg_table is physical at this point
780          */
781
782         pg_table = (pte_t *) pmd_address(*pmd);
783         if (!pg_table)
784                 pg_table = (pte_t *) __pa(get_zeroed_page(GFP_KERNEL));
785
786         __pmd_val_set(*pmd, PxD_FLAG_PRESENT | PxD_FLAG_VALID | (unsigned long) pg_table);
787
788         /* now change pg_table to kernel virtual addresses */
789
790         pg_table = (pte_t *) __va(pg_table) + start_pte;
791         set_pte(pg_table, __mk_pte(address, PAGE_GATEWAY));
792 }
793 EXPORT_SYMBOL(map_hpux_gateway_page);
794 #endif
795
796 void __init paging_init(void)
797 {
798         int i;
799
800         setup_bootmem();
801         pagetable_init();
802         gateway_init();
803         flush_cache_all_local(); /* start with known state */
804         flush_tlb_all_local(NULL);
805
806         for (i = 0; i < npmem_ranges; i++) {
807                 unsigned long zones_size[MAX_NR_ZONES] = { 0, 0, 0 };
808
809                 /* We have an IOMMU, so all memory can go into a single
810                    ZONE_DMA zone. */
811                 zones_size[ZONE_DMA] = pmem_ranges[i].pages;
812
813 #ifdef CONFIG_DISCONTIGMEM
814                 /* Need to initialize the pfnnid_map before we can initialize
815                    the zone */
816                 {
817                     int j;
818                     for (j = (pmem_ranges[i].start_pfn >> PFNNID_SHIFT);
819                          j <= ((pmem_ranges[i].start_pfn + pmem_ranges[i].pages) >> PFNNID_SHIFT);
820                          j++) {
821                         pfnnid_map[j] = i;
822                     }
823                 }
824 #endif
825
826                 free_area_init_node(i, NODE_DATA(i), zones_size,
827                                 pmem_ranges[i].start_pfn, NULL);
828         }
829 }
830
831 #ifdef CONFIG_PA20
832
833 /*
834  * Currently, all PA20 chips have 18 bit protection id's, which is the
835  * limiting factor (space ids are 32 bits).
836  */
837
838 #define NR_SPACE_IDS 262144
839
840 #else
841
842 /*
843  * Currently we have a one-to-one relationship between space id's and
844  * protection id's. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only
845  * support 15 bit protection id's, so that is the limiting factor.
846  * PCXT' has 18 bit protection id's, but only 16 bit spaceids, so it's
847  * probably not worth the effort for a special case here.
848  */
849
850 #define NR_SPACE_IDS 32768
851
852 #endif  /* !CONFIG_PA20 */
853
854 #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2)
855 #define SID_ARRAY_SIZE  (NR_SPACE_IDS / (8 * sizeof(long)))
856
857 static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */
858 static unsigned long dirty_space_id[SID_ARRAY_SIZE];
859 static unsigned long space_id_index;
860 static unsigned long free_space_ids = NR_SPACE_IDS - 1;
861 static unsigned long dirty_space_ids = 0;
862
863 static DEFINE_SPINLOCK(sid_lock);
864
865 unsigned long alloc_sid(void)
866 {
867         unsigned long index;
868
869         spin_lock(&sid_lock);
870
871         if (free_space_ids == 0) {
872                 if (dirty_space_ids != 0) {
873                         spin_unlock(&sid_lock);
874                         flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */
875                         spin_lock(&sid_lock);
876                 }
877                 if (free_space_ids == 0)
878                         BUG();
879         }
880
881         free_space_ids--;
882
883         index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
884         space_id[index >> SHIFT_PER_LONG] |= (1L << (index & (BITS_PER_LONG - 1)));
885         space_id_index = index;
886
887         spin_unlock(&sid_lock);
888
889         return index << SPACEID_SHIFT;
890 }
891
892 void free_sid(unsigned long spaceid)
893 {
894         unsigned long index = spaceid >> SPACEID_SHIFT;
895         unsigned long *dirty_space_offset;
896
897         dirty_space_offset = dirty_space_id + (index >> SHIFT_PER_LONG);
898         index &= (BITS_PER_LONG - 1);
899
900         spin_lock(&sid_lock);
901
902         if (*dirty_space_offset & (1L << index))
903             BUG(); /* attempt to free space id twice */
904
905         *dirty_space_offset |= (1L << index);
906         dirty_space_ids++;
907
908         spin_unlock(&sid_lock);
909 }
910
911
912 #ifdef CONFIG_SMP
913 static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array)
914 {
915         int i;
916
917         /* NOTE: sid_lock must be held upon entry */
918
919         *ndirtyptr = dirty_space_ids;
920         if (dirty_space_ids != 0) {
921             for (i = 0; i < SID_ARRAY_SIZE; i++) {
922                 dirty_array[i] = dirty_space_id[i];
923                 dirty_space_id[i] = 0;
924             }
925             dirty_space_ids = 0;
926         }
927
928         return;
929 }
930
931 static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array)
932 {
933         int i;
934
935         /* NOTE: sid_lock must be held upon entry */
936
937         if (ndirty != 0) {
938                 for (i = 0; i < SID_ARRAY_SIZE; i++) {
939                         space_id[i] ^= dirty_array[i];
940                 }
941
942                 free_space_ids += ndirty;
943                 space_id_index = 0;
944         }
945 }
946
947 #else /* CONFIG_SMP */
948
949 static void recycle_sids(void)
950 {
951         int i;
952
953         /* NOTE: sid_lock must be held upon entry */
954
955         if (dirty_space_ids != 0) {
956                 for (i = 0; i < SID_ARRAY_SIZE; i++) {
957                         space_id[i] ^= dirty_space_id[i];
958                         dirty_space_id[i] = 0;
959                 }
960
961                 free_space_ids += dirty_space_ids;
962                 dirty_space_ids = 0;
963                 space_id_index = 0;
964         }
965 }
966 #endif
967
968 /*
969  * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is
970  * purged, we can safely reuse the space ids that were released but
971  * not flushed from the tlb.
972  */
973
974 #ifdef CONFIG_SMP
975
976 static unsigned long recycle_ndirty;
977 static unsigned long recycle_dirty_array[SID_ARRAY_SIZE];
978 static unsigned int recycle_inuse = 0;
979
980 void flush_tlb_all(void)
981 {
982         int do_recycle;
983
984         do_recycle = 0;
985         spin_lock(&sid_lock);
986         if (dirty_space_ids > RECYCLE_THRESHOLD) {
987             if (recycle_inuse) {
988                 BUG();  /* FIXME: Use a semaphore/wait queue here */
989             }
990             get_dirty_sids(&recycle_ndirty,recycle_dirty_array);
991             recycle_inuse++;
992             do_recycle++;
993         }
994         spin_unlock(&sid_lock);
995         on_each_cpu(flush_tlb_all_local, NULL, 1, 1);
996         if (do_recycle) {
997             spin_lock(&sid_lock);
998             recycle_sids(recycle_ndirty,recycle_dirty_array);
999             recycle_inuse = 0;
1000             spin_unlock(&sid_lock);
1001         }
1002 }
1003 #else
1004 void flush_tlb_all(void)
1005 {
1006         spin_lock(&sid_lock);
1007         flush_tlb_all_local(NULL);
1008         recycle_sids();
1009         spin_unlock(&sid_lock);
1010 }
1011 #endif
1012
1013 #ifdef CONFIG_BLK_DEV_INITRD
1014 void free_initrd_mem(unsigned long start, unsigned long end)
1015 {
1016 #if 0
1017         if (start < end)
1018                 printk(KERN_INFO "Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
1019         for (; start < end; start += PAGE_SIZE) {
1020                 ClearPageReserved(virt_to_page(start));
1021                 init_page_count(virt_to_page(start));
1022                 free_page(start);
1023                 num_physpages++;
1024                 totalram_pages++;
1025         }
1026 #endif
1027 }
1028 #endif