| /* |
| * Copyright (C) 1995 Linus Torvalds |
| * Copyright 2010 Tilera Corporation. All Rights Reserved. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation, version 2. |
| * |
| * This program is distributed in the hope that it will be useful, but |
| * WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or |
| * NON INFRINGEMENT. See the GNU General Public License for |
| * more details. |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/signal.h> |
| #include <linux/sched.h> |
| #include <linux/kernel.h> |
| #include <linux/errno.h> |
| #include <linux/string.h> |
| #include <linux/types.h> |
| #include <linux/ptrace.h> |
| #include <linux/mman.h> |
| #include <linux/mm.h> |
| #include <linux/hugetlb.h> |
| #include <linux/swap.h> |
| #include <linux/smp.h> |
| #include <linux/init.h> |
| #include <linux/highmem.h> |
| #include <linux/pagemap.h> |
| #include <linux/poison.h> |
| #include <linux/bootmem.h> |
| #include <linux/slab.h> |
| #include <linux/proc_fs.h> |
| #include <linux/efi.h> |
| #include <linux/memory_hotplug.h> |
| #include <linux/uaccess.h> |
| #include <asm/mmu_context.h> |
| #include <asm/processor.h> |
| #include <asm/pgtable.h> |
| #include <asm/pgalloc.h> |
| #include <asm/dma.h> |
| #include <asm/fixmap.h> |
| #include <asm/tlb.h> |
| #include <asm/tlbflush.h> |
| #include <asm/sections.h> |
| #include <asm/setup.h> |
| #include <asm/homecache.h> |
| #include <hv/hypervisor.h> |
| #include <arch/chip.h> |
| |
| #include "migrate.h" |
| |
| #define clear_pgd(pmdptr) (*(pmdptr) = hv_pte(0)) |
| |
| #ifndef __tilegx__ |
| unsigned long VMALLOC_RESERVE = CONFIG_VMALLOC_RESERVE; |
| EXPORT_SYMBOL(VMALLOC_RESERVE); |
| #endif |
| |
| /* Create an L2 page table */ |
| static pte_t * __init alloc_pte(void) |
| { |
| return __alloc_bootmem(L2_KERNEL_PGTABLE_SIZE, HV_PAGE_TABLE_ALIGN, 0); |
| } |
| |
| /* |
| * L2 page tables per controller. We allocate these all at once from |
| * the bootmem allocator and store them here. This saves on kernel L2 |
| * page table memory, compared to allocating a full 64K page per L2 |
| * page table, and also means that in cases where we use huge pages, |
| * we are guaranteed to later be able to shatter those huge pages and |
| * switch to using these page tables instead, without requiring |
| * further allocation. Each l2_ptes[] entry points to the first page |
| * table for the first hugepage-size piece of memory on the |
| * controller; other page tables are just indexed directly, i.e. the |
| * L2 page tables are contiguous in memory for each controller. |
| */ |
| static pte_t *l2_ptes[MAX_NUMNODES]; |
| static int num_l2_ptes[MAX_NUMNODES]; |
| |
| static void init_prealloc_ptes(int node, int pages) |
| { |
| BUG_ON(pages & (PTRS_PER_PTE - 1)); |
| if (pages) { |
| num_l2_ptes[node] = pages; |
| l2_ptes[node] = __alloc_bootmem(pages * sizeof(pte_t), |
| HV_PAGE_TABLE_ALIGN, 0); |
| } |
| } |
| |
| pte_t *get_prealloc_pte(unsigned long pfn) |
| { |
| int node = pfn_to_nid(pfn); |
| pfn &= ~(-1UL << (NR_PA_HIGHBIT_SHIFT - PAGE_SHIFT)); |
| BUG_ON(node >= MAX_NUMNODES); |
| BUG_ON(pfn >= num_l2_ptes[node]); |
| return &l2_ptes[node][pfn]; |
| } |
| |
| /* |
| * What caching do we expect pages from the heap to have when |
| * they are allocated during bootup? (Once we've installed the |
| * "real" swapper_pg_dir.) |
| */ |
| static int initial_heap_home(void) |
| { |
| if (hash_default) |
| return PAGE_HOME_HASH; |
| return smp_processor_id(); |
| } |
| |
| /* |
| * Place a pointer to an L2 page table in a middle page |
| * directory entry. |
| */ |
| static void __init assign_pte(pmd_t *pmd, pte_t *page_table) |
| { |
| phys_addr_t pa = __pa(page_table); |
| unsigned long l2_ptfn = pa >> HV_LOG2_PAGE_TABLE_ALIGN; |
| pte_t pteval = hv_pte_set_ptfn(__pgprot(_PAGE_TABLE), l2_ptfn); |
| BUG_ON((pa & (HV_PAGE_TABLE_ALIGN-1)) != 0); |
| pteval = pte_set_home(pteval, initial_heap_home()); |
| *(pte_t *)pmd = pteval; |
| if (page_table != (pte_t *)pmd_page_vaddr(*pmd)) |
| BUG(); |
| } |
| |
| #ifdef __tilegx__ |
| |
| static inline pmd_t *alloc_pmd(void) |
| { |
| return __alloc_bootmem(L1_KERNEL_PGTABLE_SIZE, HV_PAGE_TABLE_ALIGN, 0); |
| } |
| |
| static inline void assign_pmd(pud_t *pud, pmd_t *pmd) |
| { |
| assign_pte((pmd_t *)pud, (pte_t *)pmd); |
| } |
| |
| #endif /* __tilegx__ */ |
| |
| /* Replace the given pmd with a full PTE table. */ |
| void __init shatter_pmd(pmd_t *pmd) |
| { |
| pte_t *pte = get_prealloc_pte(pte_pfn(*(pte_t *)pmd)); |
| assign_pte(pmd, pte); |
| } |
| |
| #ifdef __tilegx__ |
| static pmd_t *__init get_pmd(pgd_t pgtables[], unsigned long va) |
| { |
| pud_t *pud = pud_offset(&pgtables[pgd_index(va)], va); |
| if (pud_none(*pud)) |
| assign_pmd(pud, alloc_pmd()); |
| return pmd_offset(pud, va); |
| } |
| #else |
| static pmd_t *__init get_pmd(pgd_t pgtables[], unsigned long va) |
| { |
| return pmd_offset(pud_offset(&pgtables[pgd_index(va)], va), va); |
| } |
| #endif |
| |
| /* |
| * This function initializes a certain range of kernel virtual memory |
| * with new bootmem page tables, everywhere page tables are missing in |
| * the given range. |
| */ |
| |
| /* |
| * NOTE: The pagetables are allocated contiguous on the physical space |
| * so we can cache the place of the first one and move around without |
| * checking the pgd every time. |
| */ |
| static void __init page_table_range_init(unsigned long start, |
| unsigned long end, pgd_t *pgd) |
| { |
| unsigned long vaddr; |
| start = round_down(start, PMD_SIZE); |
| end = round_up(end, PMD_SIZE); |
| for (vaddr = start; vaddr < end; vaddr += PMD_SIZE) { |
| pmd_t *pmd = get_pmd(pgd, vaddr); |
| if (pmd_none(*pmd)) |
| assign_pte(pmd, alloc_pte()); |
| } |
| } |
| |
| |
| static int __initdata ktext_hash = 1; /* .text pages */ |
| static int __initdata kdata_hash = 1; /* .data and .bss pages */ |
| int __write_once hash_default = 1; /* kernel allocator pages */ |
| EXPORT_SYMBOL(hash_default); |
| int __write_once kstack_hash = 1; /* if no homecaching, use h4h */ |
| |
| /* |
| * CPUs to use to for striping the pages of kernel data. If hash-for-home |
| * is available, this is only relevant if kcache_hash sets up the |
| * .data and .bss to be page-homed, and we don't want the default mode |
| * of using the full set of kernel cpus for the striping. |
| */ |
| static __initdata struct cpumask kdata_mask; |
| static __initdata int kdata_arg_seen; |
| |
| int __write_once kdata_huge; /* if no homecaching, small pages */ |
| |
| |
| /* Combine a generic pgprot_t with cache home to get a cache-aware pgprot. */ |
| static pgprot_t __init construct_pgprot(pgprot_t prot, int home) |
| { |
| prot = pte_set_home(prot, home); |
| if (home == PAGE_HOME_IMMUTABLE) { |
| if (ktext_hash) |
| prot = hv_pte_set_mode(prot, HV_PTE_MODE_CACHE_HASH_L3); |
| else |
| prot = hv_pte_set_mode(prot, HV_PTE_MODE_CACHE_NO_L3); |
| } |
| return prot; |
| } |
| |
| /* |
| * For a given kernel data VA, how should it be cached? |
| * We return the complete pgprot_t with caching bits set. |
| */ |
| static pgprot_t __init init_pgprot(ulong address) |
| { |
| int cpu; |
| unsigned long page; |
| enum { CODE_DELTA = MEM_SV_START - PAGE_OFFSET }; |
| |
| /* For kdata=huge, everything is just hash-for-home. */ |
| if (kdata_huge) |
| return construct_pgprot(PAGE_KERNEL, PAGE_HOME_HASH); |
| |
| /* We map the aliased pages of permanent text inaccessible. */ |
| if (address < (ulong) _sinittext - CODE_DELTA) |
| return PAGE_NONE; |
| |
| /* We map read-only data non-coherent for performance. */ |
| if ((address >= (ulong) __start_rodata && |
| address < (ulong) __end_rodata) || |
| address == (ulong) empty_zero_page) { |
| return construct_pgprot(PAGE_KERNEL_RO, PAGE_HOME_IMMUTABLE); |
| } |
| |
| #ifndef __tilegx__ |
| /* Force the atomic_locks[] array page to be hash-for-home. */ |
| if (address == (ulong) atomic_locks) |
| return construct_pgprot(PAGE_KERNEL, PAGE_HOME_HASH); |
| #endif |
| |
| /* |
| * Everything else that isn't data or bss is heap, so mark it |
| * with the initial heap home (hash-for-home, or this cpu). This |
| * includes any addresses after the loaded image and any address before |
| * __init_end, since we already captured the case of text before |
| * _sinittext, and __pa(einittext) is approximately __pa(__init_begin). |
| * |
| * All the LOWMEM pages that we mark this way will get their |
| * struct page homecache properly marked later, in set_page_homes(). |
| * The HIGHMEM pages we leave with a default zero for their |
| * homes, but with a zero free_time we don't have to actually |
| * do a flush action the first time we use them, either. |
| */ |
| if (address >= (ulong) _end || address < (ulong) __init_end) |
| return construct_pgprot(PAGE_KERNEL, initial_heap_home()); |
| |
| /* Use hash-for-home if requested for data/bss. */ |
| if (kdata_hash) |
| return construct_pgprot(PAGE_KERNEL, PAGE_HOME_HASH); |
| |
| /* |
| * Otherwise we just hand out consecutive cpus. To avoid |
| * requiring this function to hold state, we just walk forward from |
| * __end_rodata by PAGE_SIZE, skipping the readonly and init data, to |
| * reach the requested address, while walking cpu home around |
| * kdata_mask. This is typically no more than a dozen or so iterations. |
| */ |
| page = (((ulong)__end_rodata) + PAGE_SIZE - 1) & PAGE_MASK; |
| BUG_ON(address < page || address >= (ulong)_end); |
| cpu = cpumask_first(&kdata_mask); |
| for (; page < address; page += PAGE_SIZE) { |
| if (page >= (ulong)&init_thread_union && |
| page < (ulong)&init_thread_union + THREAD_SIZE) |
| continue; |
| if (page == (ulong)empty_zero_page) |
| continue; |
| #ifndef __tilegx__ |
| if (page == (ulong)atomic_locks) |
| continue; |
| #endif |
| cpu = cpumask_next(cpu, &kdata_mask); |
| if (cpu == NR_CPUS) |
| cpu = cpumask_first(&kdata_mask); |
| } |
| return construct_pgprot(PAGE_KERNEL, cpu); |
| } |
| |
| /* |
| * This function sets up how we cache the kernel text. If we have |
| * hash-for-home support, normally that is used instead (see the |
| * kcache_hash boot flag for more information). But if we end up |
| * using a page-based caching technique, this option sets up the |
| * details of that. In addition, the "ktext=nocache" option may |
| * always be used to disable local caching of text pages, if desired. |
| */ |
| |
| static int __initdata ktext_arg_seen; |
| static int __initdata ktext_small; |
| static int __initdata ktext_local; |
| static int __initdata ktext_all; |
| static int __initdata ktext_nondataplane; |
| static int __initdata ktext_nocache; |
| static struct cpumask __initdata ktext_mask; |
| |
| static int __init setup_ktext(char *str) |
| { |
| if (str == NULL) |
| return -EINVAL; |
| |
| /* If you have a leading "nocache", turn off ktext caching */ |
| if (strncmp(str, "nocache", 7) == 0) { |
| ktext_nocache = 1; |
| pr_info("ktext: disabling local caching of kernel text\n"); |
| str += 7; |
| if (*str == ',') |
| ++str; |
| if (*str == '\0') |
| return 0; |
| } |
| |
| ktext_arg_seen = 1; |
| |
| /* Default setting: use a huge page */ |
| if (strcmp(str, "huge") == 0) |
| pr_info("ktext: using one huge locally cached page\n"); |
| |
| /* Pay TLB cost but get no cache benefit: cache small pages locally */ |
| else if (strcmp(str, "local") == 0) { |
| ktext_small = 1; |
| ktext_local = 1; |
| pr_info("ktext: using small pages with local caching\n"); |
| } |
| |
| /* Neighborhood cache ktext pages on all cpus. */ |
| else if (strcmp(str, "all") == 0) { |
| ktext_small = 1; |
| ktext_all = 1; |
| pr_info("ktext: using maximal caching neighborhood\n"); |
| } |
| |
| |
| /* Neighborhood ktext pages on specified mask */ |
| else if (cpulist_parse(str, &ktext_mask) == 0) { |
| char buf[NR_CPUS * 5]; |
| cpulist_scnprintf(buf, sizeof(buf), &ktext_mask); |
| if (cpumask_weight(&ktext_mask) > 1) { |
| ktext_small = 1; |
| pr_info("ktext: using caching neighborhood %s " |
| "with small pages\n", buf); |
| } else { |
| pr_info("ktext: caching on cpu %s with one huge page\n", |
| buf); |
| } |
| } |
| |
| else if (*str) |
| return -EINVAL; |
| |
| return 0; |
| } |
| |
| early_param("ktext", setup_ktext); |
| |
| |
| static inline pgprot_t ktext_set_nocache(pgprot_t prot) |
| { |
| if (!ktext_nocache) |
| prot = hv_pte_set_nc(prot); |
| else |
| prot = hv_pte_set_no_alloc_l2(prot); |
| return prot; |
| } |
| |
| /* Temporary page table we use for staging. */ |
| static pgd_t pgtables[PTRS_PER_PGD] |
| __attribute__((aligned(HV_PAGE_TABLE_ALIGN))); |
| |
| /* |
| * This maps the physical memory to kernel virtual address space, a total |
| * of max_low_pfn pages, by creating page tables starting from address |
| * PAGE_OFFSET. |
| * |
| * This routine transitions us from using a set of compiled-in large |
| * pages to using some more precise caching, including removing access |
| * to code pages mapped at PAGE_OFFSET (executed only at MEM_SV_START) |
| * marking read-only data as locally cacheable, striping the remaining |
| * .data and .bss across all the available tiles, and removing access |
| * to pages above the top of RAM (thus ensuring a page fault from a bad |
| * virtual address rather than a hypervisor shoot down for accessing |
| * memory outside the assigned limits). |
| */ |
| static void __init kernel_physical_mapping_init(pgd_t *pgd_base) |
| { |
| unsigned long long irqmask; |
| unsigned long address, pfn; |
| pmd_t *pmd; |
| pte_t *pte; |
| int pte_ofs; |
| const struct cpumask *my_cpu_mask = cpumask_of(smp_processor_id()); |
| struct cpumask kstripe_mask; |
| int rc, i; |
| |
| if (ktext_arg_seen && ktext_hash) { |
| pr_warning("warning: \"ktext\" boot argument ignored" |
| " if \"kcache_hash\" sets up text hash-for-home\n"); |
| ktext_small = 0; |
| } |
| |
| if (kdata_arg_seen && kdata_hash) { |
| pr_warning("warning: \"kdata\" boot argument ignored" |
| " if \"kcache_hash\" sets up data hash-for-home\n"); |
| } |
| |
| if (kdata_huge && !hash_default) { |
| pr_warning("warning: disabling \"kdata=huge\"; requires" |
| " kcache_hash=all or =allbutstack\n"); |
| kdata_huge = 0; |
| } |
| |
| /* |
| * Set up a mask for cpus to use for kernel striping. |
| * This is normally all cpus, but minus dataplane cpus if any. |
| * If the dataplane covers the whole chip, we stripe over |
| * the whole chip too. |
| */ |
| cpumask_copy(&kstripe_mask, cpu_possible_mask); |
| if (!kdata_arg_seen) |
| kdata_mask = kstripe_mask; |
| |
| /* Allocate and fill in L2 page tables */ |
| for (i = 0; i < MAX_NUMNODES; ++i) { |
| #ifdef CONFIG_HIGHMEM |
| unsigned long end_pfn = node_lowmem_end_pfn[i]; |
| #else |
| unsigned long end_pfn = node_end_pfn[i]; |
| #endif |
| unsigned long end_huge_pfn = 0; |
| |
| /* Pre-shatter the last huge page to allow per-cpu pages. */ |
| if (kdata_huge) |
| end_huge_pfn = end_pfn - (HPAGE_SIZE >> PAGE_SHIFT); |
| |
| pfn = node_start_pfn[i]; |
| |
| /* Allocate enough memory to hold L2 page tables for node. */ |
| init_prealloc_ptes(i, end_pfn - pfn); |
| |
| address = (unsigned long) pfn_to_kaddr(pfn); |
| while (pfn < end_pfn) { |
| BUG_ON(address & (HPAGE_SIZE-1)); |
| pmd = get_pmd(pgtables, address); |
| pte = get_prealloc_pte(pfn); |
| if (pfn < end_huge_pfn) { |
| pgprot_t prot = init_pgprot(address); |
| *(pte_t *)pmd = pte_mkhuge(pfn_pte(pfn, prot)); |
| for (pte_ofs = 0; pte_ofs < PTRS_PER_PTE; |
| pfn++, pte_ofs++, address += PAGE_SIZE) |
| pte[pte_ofs] = pfn_pte(pfn, prot); |
| } else { |
| if (kdata_huge) |
| printk(KERN_DEBUG "pre-shattered huge" |
| " page at %#lx\n", address); |
| for (pte_ofs = 0; pte_ofs < PTRS_PER_PTE; |
| pfn++, pte_ofs++, address += PAGE_SIZE) { |
| pgprot_t prot = init_pgprot(address); |
| pte[pte_ofs] = pfn_pte(pfn, prot); |
| } |
| assign_pte(pmd, pte); |
| } |
| } |
| } |
| |
| /* |
| * Set or check ktext_map now that we have cpu_possible_mask |
| * and kstripe_mask to work with. |
| */ |
| if (ktext_all) |
| cpumask_copy(&ktext_mask, cpu_possible_mask); |
| else if (ktext_nondataplane) |
| ktext_mask = kstripe_mask; |
| else if (!cpumask_empty(&ktext_mask)) { |
| /* Sanity-check any mask that was requested */ |
| struct cpumask bad; |
| cpumask_andnot(&bad, &ktext_mask, cpu_possible_mask); |
| cpumask_and(&ktext_mask, &ktext_mask, cpu_possible_mask); |
| if (!cpumask_empty(&bad)) { |
| char buf[NR_CPUS * 5]; |
| cpulist_scnprintf(buf, sizeof(buf), &bad); |
| pr_info("ktext: not using unavailable cpus %s\n", buf); |
| } |
| if (cpumask_empty(&ktext_mask)) { |
| pr_warning("ktext: no valid cpus; caching on %d.\n", |
| smp_processor_id()); |
| cpumask_copy(&ktext_mask, |
| cpumask_of(smp_processor_id())); |
| } |
| } |
| |
| address = MEM_SV_START; |
| pmd = get_pmd(pgtables, address); |
| pfn = 0; /* code starts at PA 0 */ |
| if (ktext_small) { |
| /* Allocate an L2 PTE for the kernel text */ |
| int cpu = 0; |
| pgprot_t prot = construct_pgprot(PAGE_KERNEL_EXEC, |
| PAGE_HOME_IMMUTABLE); |
| |
| if (ktext_local) { |
| if (ktext_nocache) |
| prot = hv_pte_set_mode(prot, |
| HV_PTE_MODE_UNCACHED); |
| else |
| prot = hv_pte_set_mode(prot, |
| HV_PTE_MODE_CACHE_NO_L3); |
| } else { |
| prot = hv_pte_set_mode(prot, |
| HV_PTE_MODE_CACHE_TILE_L3); |
| cpu = cpumask_first(&ktext_mask); |
| |
| prot = ktext_set_nocache(prot); |
| } |
| |
| BUG_ON(address != (unsigned long)_text); |
| pte = NULL; |
| for (; address < (unsigned long)_einittext; |
| pfn++, address += PAGE_SIZE) { |
| pte_ofs = pte_index(address); |
| if (pte_ofs == 0) { |
| if (pte) |
| assign_pte(pmd++, pte); |
| pte = alloc_pte(); |
| } |
| if (!ktext_local) { |
| prot = set_remote_cache_cpu(prot, cpu); |
| cpu = cpumask_next(cpu, &ktext_mask); |
| if (cpu == NR_CPUS) |
| cpu = cpumask_first(&ktext_mask); |
| } |
| pte[pte_ofs] = pfn_pte(pfn, prot); |
| } |
| if (pte) |
| assign_pte(pmd, pte); |
| } else { |
| pte_t pteval = pfn_pte(0, PAGE_KERNEL_EXEC); |
| pteval = pte_mkhuge(pteval); |
| if (ktext_hash) { |
| pteval = hv_pte_set_mode(pteval, |
| HV_PTE_MODE_CACHE_HASH_L3); |
| pteval = ktext_set_nocache(pteval); |
| } else |
| if (cpumask_weight(&ktext_mask) == 1) { |
| pteval = set_remote_cache_cpu(pteval, |
| cpumask_first(&ktext_mask)); |
| pteval = hv_pte_set_mode(pteval, |
| HV_PTE_MODE_CACHE_TILE_L3); |
| pteval = ktext_set_nocache(pteval); |
| } else if (ktext_nocache) |
| pteval = hv_pte_set_mode(pteval, |
| HV_PTE_MODE_UNCACHED); |
| else |
| pteval = hv_pte_set_mode(pteval, |
| HV_PTE_MODE_CACHE_NO_L3); |
| for (; address < (unsigned long)_einittext; |
| pfn += PFN_DOWN(HPAGE_SIZE), address += HPAGE_SIZE) |
| *(pte_t *)(pmd++) = pfn_pte(pfn, pteval); |
| } |
| |
| /* Set swapper_pgprot here so it is flushed to memory right away. */ |
| swapper_pgprot = init_pgprot((unsigned long)swapper_pg_dir); |
| |
| /* |
| * Since we may be changing the caching of the stack and page |
| * table itself, we invoke an assembly helper to do the |
| * following steps: |
| * |
| * - flush the cache so we start with an empty slate |
| * - install pgtables[] as the real page table |
| * - flush the TLB so the new page table takes effect |
| */ |
| irqmask = interrupt_mask_save_mask(); |
| interrupt_mask_set_mask(-1ULL); |
| rc = flush_and_install_context(__pa(pgtables), |
| init_pgprot((unsigned long)pgtables), |
| __get_cpu_var(current_asid), |
| cpumask_bits(my_cpu_mask)); |
| interrupt_mask_restore_mask(irqmask); |
| BUG_ON(rc != 0); |
| |
| /* Copy the page table back to the normal swapper_pg_dir. */ |
| memcpy(pgd_base, pgtables, sizeof(pgtables)); |
| __install_page_table(pgd_base, __get_cpu_var(current_asid), |
| swapper_pgprot); |
| |
| /* |
| * We just read swapper_pgprot and thus brought it into the cache, |
| * with its new home & caching mode. When we start the other CPUs, |
| * they're going to reference swapper_pgprot via their initial fake |
| * VA-is-PA mappings, which cache everything locally. At that |
| * time, if it's in our cache with a conflicting home, the |
| * simulator's coherence checker will complain. So, flush it out |
| * of our cache; we're not going to ever use it again anyway. |
| */ |
| __insn_finv(&swapper_pgprot); |
| } |
| |
| /* |
| * devmem_is_allowed() checks to see if /dev/mem access to a certain address |
| * is valid. The argument is a physical page number. |
| * |
| * On Tile, the only valid things for which we can just hand out unchecked |
| * PTEs are the kernel code and data. Anything else might change its |
| * homing with time, and we wouldn't know to adjust the /dev/mem PTEs. |
| * Note that init_thread_union is released to heap soon after boot, |
| * so we include it in the init data. |
| * |
| * For TILE-Gx, we might want to consider allowing access to PA |
| * regions corresponding to PCI space, etc. |
| */ |
| int devmem_is_allowed(unsigned long pagenr) |
| { |
| return pagenr < kaddr_to_pfn(_end) && |
| !(pagenr >= kaddr_to_pfn(&init_thread_union) || |
| pagenr < kaddr_to_pfn(__init_end)) && |
| !(pagenr >= kaddr_to_pfn(_sinittext) || |
| pagenr <= kaddr_to_pfn(_einittext-1)); |
| } |
| |
| #ifdef CONFIG_HIGHMEM |
| static void __init permanent_kmaps_init(pgd_t *pgd_base) |
| { |
| pgd_t *pgd; |
| pud_t *pud; |
| pmd_t *pmd; |
| pte_t *pte; |
| unsigned long vaddr; |
| |
| vaddr = PKMAP_BASE; |
| page_table_range_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base); |
| |
| pgd = swapper_pg_dir + pgd_index(vaddr); |
| pud = pud_offset(pgd, vaddr); |
| pmd = pmd_offset(pud, vaddr); |
| pte = pte_offset_kernel(pmd, vaddr); |
| pkmap_page_table = pte; |
| } |
| #endif /* CONFIG_HIGHMEM */ |
| |
| |
| #ifndef CONFIG_64BIT |
| static void __init init_free_pfn_range(unsigned long start, unsigned long end) |
| { |
| unsigned long pfn; |
| struct page *page = pfn_to_page(start); |
| |
| for (pfn = start; pfn < end; ) { |
| /* Optimize by freeing pages in large batches */ |
| int order = __ffs(pfn); |
| int count, i; |
| struct page *p; |
| |
| if (order >= MAX_ORDER) |
| order = MAX_ORDER-1; |
| count = 1 << order; |
| while (pfn + count > end) { |
| count >>= 1; |
| --order; |
| } |
| for (p = page, i = 0; i < count; ++i, ++p) { |
| __ClearPageReserved(p); |
| /* |
| * Hacky direct set to avoid unnecessary |
| * lock take/release for EVERY page here. |
| */ |
| p->_count.counter = 0; |
| p->_mapcount.counter = -1; |
| } |
| init_page_count(page); |
| __free_pages(page, order); |
| adjust_managed_page_count(page, count); |
| |
| page += count; |
| pfn += count; |
| } |
| } |
| |
| static void __init set_non_bootmem_pages_init(void) |
| { |
| struct zone *z; |
| for_each_zone(z) { |
| unsigned long start, end; |
| int nid = z->zone_pgdat->node_id; |
| #ifdef CONFIG_HIGHMEM |
| int idx = zone_idx(z); |
| #endif |
| |
| start = z->zone_start_pfn; |
| end = start + z->spanned_pages; |
| start = max(start, node_free_pfn[nid]); |
| start = max(start, max_low_pfn); |
| |
| #ifdef CONFIG_HIGHMEM |
| if (idx == ZONE_HIGHMEM) |
| totalhigh_pages += z->spanned_pages; |
| #endif |
| if (kdata_huge) { |
| unsigned long percpu_pfn = node_percpu_pfn[nid]; |
| if (start < percpu_pfn && end > percpu_pfn) |
| end = percpu_pfn; |
| } |
| #ifdef CONFIG_PCI |
| if (start <= pci_reserve_start_pfn && |
| end > pci_reserve_start_pfn) { |
| if (end > pci_reserve_end_pfn) |
| init_free_pfn_range(pci_reserve_end_pfn, end); |
| end = pci_reserve_start_pfn; |
| } |
| #endif |
| init_free_pfn_range(start, end); |
| } |
| } |
| #endif |
| |
| /* |
| * paging_init() sets up the page tables - note that all of lowmem is |
| * already mapped by head.S. |
| */ |
| void __init paging_init(void) |
| { |
| #ifdef __tilegx__ |
| pud_t *pud; |
| #endif |
| pgd_t *pgd_base = swapper_pg_dir; |
| |
| kernel_physical_mapping_init(pgd_base); |
| |
| /* Fixed mappings, only the page table structure has to be created. */ |
| page_table_range_init(fix_to_virt(__end_of_fixed_addresses - 1), |
| FIXADDR_TOP, pgd_base); |
| |
| #ifdef CONFIG_HIGHMEM |
| permanent_kmaps_init(pgd_base); |
| #endif |
| |
| #ifdef __tilegx__ |
| /* |
| * Since GX allocates just one pmd_t array worth of vmalloc space, |
| * we go ahead and allocate it statically here, then share it |
| * globally. As a result we don't have to worry about any task |
| * changing init_mm once we get up and running, and there's no |
| * need for e.g. vmalloc_sync_all(). |
| */ |
| BUILD_BUG_ON(pgd_index(VMALLOC_START) != pgd_index(VMALLOC_END - 1)); |
| pud = pud_offset(pgd_base + pgd_index(VMALLOC_START), VMALLOC_START); |
| assign_pmd(pud, alloc_pmd()); |
| #endif |
| } |
| |
| |
| /* |
| * Walk the kernel page tables and derive the page_home() from |
| * the PTEs, so that set_pte() can properly validate the caching |
| * of all PTEs it sees. |
| */ |
| void __init set_page_homes(void) |
| { |
| } |
| |
| static void __init set_max_mapnr_init(void) |
| { |
| #ifdef CONFIG_FLATMEM |
| max_mapnr = max_low_pfn; |
| #endif |
| } |
| |
| void __init mem_init(void) |
| { |
| int i; |
| #ifndef __tilegx__ |
| void *last; |
| #endif |
| |
| #ifdef CONFIG_FLATMEM |
| BUG_ON(!mem_map); |
| #endif |
| |
| #ifdef CONFIG_HIGHMEM |
| /* check that fixmap and pkmap do not overlap */ |
| if (PKMAP_ADDR(LAST_PKMAP-1) >= FIXADDR_START) { |
| pr_err("fixmap and kmap areas overlap" |
| " - this will crash\n"); |
| pr_err("pkstart: %lxh pkend: %lxh fixstart %lxh\n", |
| PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP-1), |
| FIXADDR_START); |
| BUG(); |
| } |
| #endif |
| |
| set_max_mapnr_init(); |
| |
| /* this will put all bootmem onto the freelists */ |
| free_all_bootmem(); |
| |
| #ifndef CONFIG_64BIT |
| /* count all remaining LOWMEM and give all HIGHMEM to page allocator */ |
| set_non_bootmem_pages_init(); |
| #endif |
| |
| mem_init_print_info(NULL); |
| |
| /* |
| * In debug mode, dump some interesting memory mappings. |
| */ |
| #ifdef CONFIG_HIGHMEM |
| printk(KERN_DEBUG " KMAP %#lx - %#lx\n", |
| FIXADDR_START, FIXADDR_TOP + PAGE_SIZE - 1); |
| printk(KERN_DEBUG " PKMAP %#lx - %#lx\n", |
| PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP) - 1); |
| #endif |
| printk(KERN_DEBUG " VMALLOC %#lx - %#lx\n", |
| _VMALLOC_START, _VMALLOC_END - 1); |
| #ifdef __tilegx__ |
| for (i = MAX_NUMNODES-1; i >= 0; --i) { |
| struct pglist_data *node = &node_data[i]; |
| if (node->node_present_pages) { |
| unsigned long start = (unsigned long) |
| pfn_to_kaddr(node->node_start_pfn); |
| unsigned long end = start + |
| (node->node_present_pages << PAGE_SHIFT); |
| printk(KERN_DEBUG " MEM%d %#lx - %#lx\n", |
| i, start, end - 1); |
| } |
| } |
| #else |
| last = high_memory; |
| for (i = MAX_NUMNODES-1; i >= 0; --i) { |
| if ((unsigned long)vbase_map[i] != -1UL) { |
| printk(KERN_DEBUG " LOWMEM%d %#lx - %#lx\n", |
| i, (unsigned long) (vbase_map[i]), |
| (unsigned long) (last-1)); |
| last = vbase_map[i]; |
| } |
| } |
| #endif |
| |
| #ifndef __tilegx__ |
| /* |
| * Convert from using one lock for all atomic operations to |
| * one per cpu. |
| */ |
| __init_atomic_per_cpu(); |
| #endif |
| } |
| |
| /* |
| * this is for the non-NUMA, single node SMP system case. |
| * Specifically, in the case of x86, we will always add |
| * memory to the highmem for now. |
| */ |
| #ifndef CONFIG_NEED_MULTIPLE_NODES |
| int arch_add_memory(u64 start, u64 size) |
| { |
| struct pglist_data *pgdata = &contig_page_data; |
| struct zone *zone = pgdata->node_zones + MAX_NR_ZONES-1; |
| unsigned long start_pfn = start >> PAGE_SHIFT; |
| unsigned long nr_pages = size >> PAGE_SHIFT; |
| |
| return __add_pages(zone, start_pfn, nr_pages); |
| } |
| |
| int remove_memory(u64 start, u64 size) |
| { |
| return -EINVAL; |
| } |
| |
| #ifdef CONFIG_MEMORY_HOTREMOVE |
| int arch_remove_memory(u64 start, u64 size) |
| { |
| /* TODO */ |
| return -EBUSY; |
| } |
| #endif |
| #endif |
| |
| struct kmem_cache *pgd_cache; |
| |
| void __init pgtable_cache_init(void) |
| { |
| pgd_cache = kmem_cache_create("pgd", SIZEOF_PGD, SIZEOF_PGD, 0, NULL); |
| if (!pgd_cache) |
| panic("pgtable_cache_init(): Cannot create pgd cache"); |
| } |
| |
| #ifdef CONFIG_DEBUG_PAGEALLOC |
| static long __write_once initfree; |
| #else |
| static long __write_once initfree = 1; |
| #endif |
| |
| /* Select whether to free (1) or mark unusable (0) the __init pages. */ |
| static int __init set_initfree(char *str) |
| { |
| long val; |
| if (kstrtol(str, 0, &val) == 0) { |
| initfree = val; |
| pr_info("initfree: %s free init pages\n", |
| initfree ? "will" : "won't"); |
| } |
| return 1; |
| } |
| __setup("initfree=", set_initfree); |
| |
| static void free_init_pages(char *what, unsigned long begin, unsigned long end) |
| { |
| unsigned long addr = (unsigned long) begin; |
| |
| if (kdata_huge && !initfree) { |
| pr_warning("Warning: ignoring initfree=0:" |
| " incompatible with kdata=huge\n"); |
| initfree = 1; |
| } |
| end = (end + PAGE_SIZE - 1) & PAGE_MASK; |
| local_flush_tlb_pages(NULL, begin, PAGE_SIZE, end - begin); |
| for (addr = begin; addr < end; addr += PAGE_SIZE) { |
| /* |
| * Note we just reset the home here directly in the |
| * page table. We know this is safe because our caller |
| * just flushed the caches on all the other cpus, |
| * and they won't be touching any of these pages. |
| */ |
| int pfn = kaddr_to_pfn((void *)addr); |
| struct page *page = pfn_to_page(pfn); |
| pte_t *ptep = virt_to_kpte(addr); |
| if (!initfree) { |
| /* |
| * If debugging page accesses then do not free |
| * this memory but mark them not present - any |
| * buggy init-section access will create a |
| * kernel page fault: |
| */ |
| pte_clear(&init_mm, addr, ptep); |
| continue; |
| } |
| if (pte_huge(*ptep)) |
| BUG_ON(!kdata_huge); |
| else |
| set_pte_at(&init_mm, addr, ptep, |
| pfn_pte(pfn, PAGE_KERNEL)); |
| memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE); |
| free_reserved_page(page); |
| } |
| pr_info("Freeing %s: %ldk freed\n", what, (end - begin) >> 10); |
| } |
| |
| void free_initmem(void) |
| { |
| const unsigned long text_delta = MEM_SV_START - PAGE_OFFSET; |
| |
| /* |
| * Evict the cache on all cores to avoid incoherence. |
| * We are guaranteed that no one will touch the init pages any more. |
| */ |
| homecache_evict(&cpu_cacheable_map); |
| |
| /* Free the data pages that we won't use again after init. */ |
| free_init_pages("unused kernel data", |
| (unsigned long)__init_begin, |
| (unsigned long)__init_end); |
| |
| /* |
| * Free the pages mapped from 0xc0000000 that correspond to code |
| * pages from MEM_SV_START that we won't use again after init. |
| */ |
| free_init_pages("unused kernel text", |
| (unsigned long)_sinittext - text_delta, |
| (unsigned long)_einittext - text_delta); |
| /* Do a global TLB flush so everyone sees the changes. */ |
| flush_tlb_all(); |
| } |