// SPDX-License-Identifier: GPL-2.0 /* * linux/arch/parisc/mm/init.c * * Copyright (C) 1995 Linus Torvalds * Copyright 1999 SuSE GmbH * changed by Philipp Rumpf * Copyright 1999 Philipp Rumpf (prumpf@tux.org) * Copyright 2004 Randolph Chung (tausq@debian.org) * Copyright 2006-2007 Helge Deller (deller@gmx.de) * */ #include #include #include #include #include #include #include #include #include #include /* for node_online_map */ #include /* for release_pages */ #include #include #include #include #include #include #include #include #include #include #include extern int data_start; extern void parisc_kernel_start(void); /* Kernel entry point in head.S */ #if CONFIG_PGTABLE_LEVELS == 3 pmd_t pmd0[PTRS_PER_PMD] __section(".data..vm0.pmd") __attribute__ ((aligned(PAGE_SIZE))); #endif pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(".data..vm0.pgd") __attribute__ ((aligned(PAGE_SIZE))); pte_t pg0[PT_INITIAL * PTRS_PER_PTE] __section(".data..vm0.pte") __attribute__ ((aligned(PAGE_SIZE))); static struct resource data_resource = { .name = "Kernel data", .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, }; static struct resource code_resource = { .name = "Kernel code", .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, }; static struct resource pdcdata_resource = { .name = "PDC data (Page Zero)", .start = 0, .end = 0x9ff, .flags = IORESOURCE_BUSY | IORESOURCE_MEM, }; static struct resource sysram_resources[MAX_PHYSMEM_RANGES] __ro_after_init; /* The following array is initialized from the firmware specific * information retrieved in kernel/inventory.c. */ physmem_range_t pmem_ranges[MAX_PHYSMEM_RANGES] __initdata; int npmem_ranges __initdata; #ifdef CONFIG_64BIT #define MAX_MEM (1UL << MAX_PHYSMEM_BITS) #else /* !CONFIG_64BIT */ #define MAX_MEM (3584U*1024U*1024U) #endif /* !CONFIG_64BIT */ static unsigned long mem_limit __read_mostly = MAX_MEM; static void __init mem_limit_func(void) { char *cp, *end; unsigned long limit; /* We need this before __setup() functions are called */ limit = MAX_MEM; for (cp = boot_command_line; *cp; ) { if (memcmp(cp, "mem=", 4) == 0) { cp += 4; limit = memparse(cp, &end); if (end != cp) break; cp = end; } else { while (*cp != ' ' && *cp) ++cp; while (*cp == ' ') ++cp; } } if (limit < mem_limit) mem_limit = limit; } #define MAX_GAP (0x40000000UL >> PAGE_SHIFT) static void __init setup_bootmem(void) { unsigned long mem_max; #ifndef CONFIG_SPARSEMEM physmem_range_t pmem_holes[MAX_PHYSMEM_RANGES - 1]; int npmem_holes; #endif int i, sysram_resource_count; disable_sr_hashing(); /* Turn off space register hashing */ /* * Sort the ranges. Since the number of ranges is typically * small, and performance is not an issue here, just do * a simple insertion sort. */ for (i = 1; i < npmem_ranges; i++) { int j; for (j = i; j > 0; j--) { if (pmem_ranges[j-1].start_pfn < pmem_ranges[j].start_pfn) { break; } swap(pmem_ranges[j-1], pmem_ranges[j]); } } #ifndef CONFIG_SPARSEMEM /* * Throw out ranges that are too far apart (controlled by * MAX_GAP). */ for (i = 1; i < npmem_ranges; i++) { if (pmem_ranges[i].start_pfn - (pmem_ranges[i-1].start_pfn + pmem_ranges[i-1].pages) > MAX_GAP) { npmem_ranges = i; printk("Large gap in memory detected (%ld pages). " "Consider turning on CONFIG_SPARSEMEM\n", pmem_ranges[i].start_pfn - (pmem_ranges[i-1].start_pfn + pmem_ranges[i-1].pages)); break; } } #endif /* Print the memory ranges */ pr_info("Memory Ranges:\n"); for (i = 0; i < npmem_ranges; i++) { struct resource *res = &sysram_resources[i]; unsigned long start; unsigned long size; size = (pmem_ranges[i].pages << PAGE_SHIFT); start = (pmem_ranges[i].start_pfn << PAGE_SHIFT); pr_info("%2d) Start 0x%016lx End 0x%016lx Size %6ld MB\n", i, start, start + (size - 1), size >> 20); /* request memory resource */ res->name = "System RAM"; res->start = start; res->end = start + size - 1; res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; request_resource(&iomem_resource, res); } sysram_resource_count = npmem_ranges; /* * For 32 bit kernels we limit the amount of memory we can * support, in order to preserve enough kernel address space * for other purposes. For 64 bit kernels we don't normally * limit the memory, but this mechanism can be used to * artificially limit the amount of memory (and it is written * to work with multiple memory ranges). */ mem_limit_func(); /* check for "mem=" argument */ mem_max = 0; for (i = 0; i < npmem_ranges; i++) { unsigned long rsize; rsize = pmem_ranges[i].pages << PAGE_SHIFT; if ((mem_max + rsize) > mem_limit) { printk(KERN_WARNING "Memory truncated to %ld MB\n", mem_limit >> 20); if (mem_max == mem_limit) npmem_ranges = i; else { pmem_ranges[i].pages = (mem_limit >> PAGE_SHIFT) - (mem_max >> PAGE_SHIFT); npmem_ranges = i + 1; mem_max = mem_limit; } break; } mem_max += rsize; } printk(KERN_INFO "Total Memory: %ld MB\n",mem_max >> 20); #ifndef CONFIG_SPARSEMEM /* Merge the ranges, keeping track of the holes */ { unsigned long end_pfn; unsigned long hole_pages; npmem_holes = 0; end_pfn = pmem_ranges[0].start_pfn + pmem_ranges[0].pages; for (i = 1; i < npmem_ranges; i++) { hole_pages = pmem_ranges[i].start_pfn - end_pfn; if (hole_pages) { pmem_holes[npmem_holes].start_pfn = end_pfn; pmem_holes[npmem_holes++].pages = hole_pages; end_pfn += hole_pages; } end_pfn += pmem_ranges[i].pages; } pmem_ranges[0].pages = end_pfn - pmem_ranges[0].start_pfn; npmem_ranges = 1; } #endif /* * Initialize and free the full range of memory in each range. */ max_pfn = 0; for (i = 0; i < npmem_ranges; i++) { unsigned long start_pfn; unsigned long npages; unsigned long start; unsigned long size; start_pfn = pmem_ranges[i].start_pfn; npages = pmem_ranges[i].pages; start = start_pfn << PAGE_SHIFT; size = npages << PAGE_SHIFT; /* add system RAM memblock */ memblock_add(start, size); if ((start_pfn + npages) > max_pfn) max_pfn = start_pfn + npages; } /* * We can't use memblock top-down allocations because we only * created the initial mapping up to KERNEL_INITIAL_SIZE in * the assembly bootup code. */ memblock_set_bottom_up(true); /* IOMMU is always used to access "high mem" on those boxes * that can support enough mem that a PCI device couldn't * directly DMA to any physical addresses. * ISA DMA support will need to revisit this. */ max_low_pfn = max_pfn; /* reserve PAGE0 pdc memory, kernel text/data/bss & bootmap */ #define PDC_CONSOLE_IO_IODC_SIZE 32768 memblock_reserve(0UL, (unsigned long)(PAGE0->mem_free + PDC_CONSOLE_IO_IODC_SIZE)); memblock_reserve(__pa(KERNEL_BINARY_TEXT_START), (unsigned long)(_end - KERNEL_BINARY_TEXT_START)); #ifndef CONFIG_SPARSEMEM /* reserve the holes */ for (i = 0; i < npmem_holes; i++) { memblock_reserve((pmem_holes[i].start_pfn << PAGE_SHIFT), (pmem_holes[i].pages << PAGE_SHIFT)); } #endif #ifdef CONFIG_BLK_DEV_INITRD if (initrd_start) { printk(KERN_INFO "initrd: %08lx-%08lx\n", initrd_start, initrd_end); if (__pa(initrd_start) < mem_max) { unsigned long initrd_reserve; if (__pa(initrd_end) > mem_max) { initrd_reserve = mem_max - __pa(initrd_start); } else { initrd_reserve = initrd_end - initrd_start; } initrd_below_start_ok = 1; printk(KERN_INFO "initrd: reserving %08lx-%08lx (mem_max %08lx)\n", __pa(initrd_start), __pa(initrd_start) + initrd_reserve, mem_max); memblock_reserve(__pa(initrd_start), initrd_reserve); } } #endif data_resource.start = virt_to_phys(&data_start); data_resource.end = virt_to_phys(_end) - 1; code_resource.start = virt_to_phys(_text); code_resource.end = virt_to_phys(&data_start)-1; /* We don't know which region the kernel will be in, so try * all of them. */ for (i = 0; i < sysram_resource_count; i++) { struct resource *res = &sysram_resources[i]; request_resource(res, &code_resource); request_resource(res, &data_resource); } request_resource(&sysram_resources[0], &pdcdata_resource); /* Initialize Page Deallocation Table (PDT) and check for bad memory. */ pdc_pdt_init(); memblock_allow_resize(); memblock_dump_all(); } static bool kernel_set_to_readonly; static void __ref map_pages(unsigned long start_vaddr, unsigned long start_paddr, unsigned long size, pgprot_t pgprot, int force) { pmd_t *pmd; pte_t *pg_table; unsigned long end_paddr; unsigned long start_pmd; unsigned long start_pte; unsigned long tmp1; unsigned long tmp2; unsigned long address; unsigned long vaddr; unsigned long ro_start; unsigned long ro_end; unsigned long kernel_start, kernel_end; ro_start = __pa((unsigned long)_text); ro_end = __pa((unsigned long)&data_start); kernel_start = __pa((unsigned long)&__init_begin); kernel_end = __pa((unsigned long)&_end); end_paddr = start_paddr + size; /* for 2-level configuration PTRS_PER_PMD is 0 so start_pmd will be 0 */ start_pmd = ((start_vaddr >> PMD_SHIFT) & (PTRS_PER_PMD - 1)); start_pte = ((start_vaddr >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)); address = start_paddr; vaddr = start_vaddr; while (address < end_paddr) { pgd_t *pgd = pgd_offset_k(vaddr); p4d_t *p4d = p4d_offset(pgd, vaddr); pud_t *pud = pud_offset(p4d, vaddr); #if CONFIG_PGTABLE_LEVELS == 3 if (pud_none(*pud)) { pmd = memblock_alloc(PAGE_SIZE << PMD_TABLE_ORDER, PAGE_SIZE << PMD_TABLE_ORDER); if (!pmd) panic("pmd allocation failed.\n"); pud_populate(NULL, pud, pmd); } #endif pmd = pmd_offset(pud, vaddr); for (tmp1 = start_pmd; tmp1 < PTRS_PER_PMD; tmp1++, pmd++) { if (pmd_none(*pmd)) { pg_table = memblock_alloc(PAGE_SIZE, PAGE_SIZE); if (!pg_table) panic("page table allocation failed\n"); pmd_populate_kernel(NULL, pmd, pg_table); } pg_table = pte_offset_kernel(pmd, vaddr); for (tmp2 = start_pte; tmp2 < PTRS_PER_PTE; tmp2++, pg_table++) { pte_t pte; pgprot_t prot; bool huge = false; if (force) { prot = pgprot; } else if (address < kernel_start || address >= kernel_end) { /* outside kernel memory */ prot = PAGE_KERNEL; } else if (!kernel_set_to_readonly) { /* still initializing, allow writing to RO memory */ prot = PAGE_KERNEL_RWX; huge = true; } else if (address >= ro_start) { /* Code (ro) and Data areas */ prot = (address < ro_end) ? PAGE_KERNEL_EXEC : PAGE_KERNEL; huge = true; } else { prot = PAGE_KERNEL; } pte = __mk_pte(address, prot); if (huge) pte = pte_mkhuge(pte); if (address >= end_paddr) break; set_pte(pg_table, pte); address += PAGE_SIZE; vaddr += PAGE_SIZE; } start_pte = 0; if (address >= end_paddr) break; } start_pmd = 0; } } void __init set_kernel_text_rw(int enable_read_write) { unsigned long start = (unsigned long) __init_begin; unsigned long end = (unsigned long) &data_start; map_pages(start, __pa(start), end-start, PAGE_KERNEL_RWX, enable_read_write ? 1:0); /* force the kernel to see the new page table entries */ flush_cache_all(); flush_tlb_all(); } void free_initmem(void) { unsigned long init_begin = (unsigned long)__init_begin; unsigned long init_end = (unsigned long)__init_end; unsigned long kernel_end = (unsigned long)&_end; /* Remap kernel text and data, but do not touch init section yet. */ kernel_set_to_readonly = true; map_pages(init_end, __pa(init_end), kernel_end - init_end, PAGE_KERNEL, 0); /* The init text pages are marked R-X. We have to * flush the icache and mark them RW- * * Do a dummy remap of the data section first (the data * section is already PAGE_KERNEL) to pull in the TLB entries * for map_kernel */ map_pages(init_begin, __pa(init_begin), init_end - init_begin, PAGE_KERNEL_RWX, 1); /* now remap at PAGE_KERNEL since the TLB is pre-primed to execute * map_pages */ map_pages(init_begin, __pa(init_begin), init_end - init_begin, PAGE_KERNEL, 1); /* force the kernel to see the new TLB entries */ __flush_tlb_range(0, init_begin, kernel_end); /* finally dump all the instructions which were cached, since the * pages are no-longer executable */ flush_icache_range(init_begin, init_end); free_initmem_default(POISON_FREE_INITMEM); /* set up a new led state on systems shipped LED State panel */ pdc_chassis_send_status(PDC_CHASSIS_DIRECT_BCOMPLETE); } #ifdef CONFIG_STRICT_KERNEL_RWX void mark_rodata_ro(void) { /* rodata memory was already mapped with KERNEL_RO access rights by pagetable_init() and map_pages(). No need to do additional stuff here */ unsigned long roai_size = __end_ro_after_init - __start_ro_after_init; pr_info("Write protected read-only-after-init data: %luk\n", roai_size >> 10); } #endif /* * Just an arbitrary offset to serve as a "hole" between mapping areas * (between top of physical memory and a potential pcxl dma mapping * area, and below the vmalloc mapping area). * * The current 32K value just means that there will be a 32K "hole" * between mapping areas. That means that any out-of-bounds memory * accesses will hopefully be caught. The vmalloc() routines leaves * a hole of 4kB between each vmalloced area for the same reason. */ /* Leave room for gateway page expansion */ #if KERNEL_MAP_START < GATEWAY_PAGE_SIZE #error KERNEL_MAP_START is in gateway reserved region #endif #define MAP_START (KERNEL_MAP_START) #define VM_MAP_OFFSET (32*1024) #define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \ & ~(VM_MAP_OFFSET-1))) void *parisc_vmalloc_start __ro_after_init; EXPORT_SYMBOL(parisc_vmalloc_start); void __init mem_init(void) { /* Do sanity checks on IPC (compat) structures */ BUILD_BUG_ON(sizeof(struct ipc64_perm) != 48); #ifndef CONFIG_64BIT BUILD_BUG_ON(sizeof(struct semid64_ds) != 80); BUILD_BUG_ON(sizeof(struct msqid64_ds) != 104); BUILD_BUG_ON(sizeof(struct shmid64_ds) != 104); #endif #ifdef CONFIG_COMPAT BUILD_BUG_ON(sizeof(struct compat_ipc64_perm) != sizeof(struct ipc64_perm)); BUILD_BUG_ON(sizeof(struct compat_semid64_ds) != 80); BUILD_BUG_ON(sizeof(struct compat_msqid64_ds) != 104); BUILD_BUG_ON(sizeof(struct compat_shmid64_ds) != 104); #endif /* Do sanity checks on page table constants */ BUILD_BUG_ON(PTE_ENTRY_SIZE != sizeof(pte_t)); BUILD_BUG_ON(PMD_ENTRY_SIZE != sizeof(pmd_t)); BUILD_BUG_ON(PGD_ENTRY_SIZE != sizeof(pgd_t)); BUILD_BUG_ON(PAGE_SHIFT + BITS_PER_PTE + BITS_PER_PMD + BITS_PER_PGD > BITS_PER_LONG); #if CONFIG_PGTABLE_LEVELS == 3 BUILD_BUG_ON(PT_INITIAL > PTRS_PER_PMD); #else BUILD_BUG_ON(PT_INITIAL > PTRS_PER_PGD); #endif #ifdef CONFIG_64BIT /* avoid ldil_%L() asm statements to sign-extend into upper 32-bits */ BUILD_BUG_ON(__PAGE_OFFSET >= 0x80000000); BUILD_BUG_ON(TMPALIAS_MAP_START >= 0x80000000); #endif high_memory = __va((max_pfn << PAGE_SHIFT)); set_max_mapnr(max_low_pfn); memblock_free_all(); #ifdef CONFIG_PA11 if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl) { pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(MAP_START); parisc_vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start + PCXL_DMA_MAP_SIZE); } else #endif parisc_vmalloc_start = SET_MAP_OFFSET(MAP_START); #if 0 /* * Do not expose the virtual kernel memory layout to userspace. * But keep code for debugging purposes. */ printk("virtual kernel memory layout:\n" " vmalloc : 0x%px - 0x%px (%4ld MB)\n" " fixmap : 0x%px - 0x%px (%4ld kB)\n" " memory : 0x%px - 0x%px (%4ld MB)\n" " .init : 0x%px - 0x%px (%4ld kB)\n" " .data : 0x%px - 0x%px (%4ld kB)\n" " .text : 0x%px - 0x%px (%4ld kB)\n", (void*)VMALLOC_START, (void*)VMALLOC_END, (VMALLOC_END - VMALLOC_START) >> 20, (void *)FIXMAP_START, (void *)(FIXMAP_START + FIXMAP_SIZE), (unsigned long)(FIXMAP_SIZE / 1024), __va(0), high_memory, ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20, __init_begin, __init_end, ((unsigned long)__init_end - (unsigned long)__init_begin) >> 10, _etext, _edata, ((unsigned long)_edata - (unsigned long)_etext) >> 10, _text, _etext, ((unsigned long)_etext - (unsigned long)_text) >> 10); #endif } unsigned long *empty_zero_page __ro_after_init; EXPORT_SYMBOL(empty_zero_page); /* * pagetable_init() sets up the page tables * * Note that gateway_init() places the Linux gateway page at page 0. * Since gateway pages cannot be dereferenced this has the desirable * side effect of trapping those pesky NULL-reference errors in the * kernel. */ static void __init pagetable_init(void) { int range; /* Map each physical memory range to its kernel vaddr */ for (range = 0; range < npmem_ranges; range++) { unsigned long start_paddr; unsigned long size; start_paddr = pmem_ranges[range].start_pfn << PAGE_SHIFT; size = pmem_ranges[range].pages << PAGE_SHIFT; map_pages((unsigned long)__va(start_paddr), start_paddr, size, PAGE_KERNEL, 0); } #ifdef CONFIG_BLK_DEV_INITRD if (initrd_end && initrd_end > mem_limit) { printk(KERN_INFO "initrd: mapping %08lx-%08lx\n", initrd_start, initrd_end); map_pages(initrd_start, __pa(initrd_start), initrd_end - initrd_start, PAGE_KERNEL, 0); } #endif empty_zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE); if (!empty_zero_page) panic("zero page allocation failed.\n"); } static void __init gateway_init(void) { unsigned long linux_gateway_page_addr; /* FIXME: This is 'const' in order to trick the compiler into not treating it as DP-relative data. */ extern void * const linux_gateway_page; linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK; /* * Setup Linux Gateway page. * * The Linux gateway page will reside in kernel space (on virtual * page 0), so it doesn't need to be aliased into user space. */ map_pages(linux_gateway_page_addr, __pa(&linux_gateway_page), PAGE_SIZE, PAGE_GATEWAY, 1); } static void __init fixmap_init(void) { unsigned long addr = FIXMAP_START; unsigned long end = FIXMAP_START + FIXMAP_SIZE; pgd_t *pgd = pgd_offset_k(addr); p4d_t *p4d = p4d_offset(pgd, addr); pud_t *pud = pud_offset(p4d, addr); pmd_t *pmd; BUILD_BUG_ON(FIXMAP_SIZE > PMD_SIZE); #if CONFIG_PGTABLE_LEVELS == 3 if (pud_none(*pud)) { pmd = memblock_alloc(PAGE_SIZE << PMD_TABLE_ORDER, PAGE_SIZE << PMD_TABLE_ORDER); if (!pmd) panic("fixmap: pmd allocation failed.\n"); pud_populate(NULL, pud, pmd); } #endif pmd = pmd_offset(pud, addr); do { pte_t *pte = memblock_alloc(PAGE_SIZE, PAGE_SIZE); if (!pte) panic("fixmap: pte allocation failed.\n"); pmd_populate_kernel(&init_mm, pmd, pte); addr += PAGE_SIZE; } while (addr < end); } static void __init parisc_bootmem_free(void) { unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, }; max_zone_pfn[0] = memblock_end_of_DRAM(); free_area_init(max_zone_pfn); } void __init paging_init(void) { setup_bootmem(); pagetable_init(); gateway_init(); fixmap_init(); flush_cache_all_local(); /* start with known state */ flush_tlb_all_local(NULL); sparse_init(); parisc_bootmem_free(); } static void alloc_btlb(unsigned long start, unsigned long end, int *slot, unsigned long entry_info) { const int slot_max = btlb_info.fixed_range_info.num_comb; int min_num_pages = btlb_info.min_size; unsigned long size; /* map at minimum 4 pages */ if (min_num_pages < 4) min_num_pages = 4; size = HUGEPAGE_SIZE; while (start < end && *slot < slot_max && size >= PAGE_SIZE) { /* starting address must have same alignment as size! */ /* if correctly aligned and fits in double size, increase */ if (((start & (2 * size - 1)) == 0) && (end - start) >= (2 * size)) { size <<= 1; continue; } /* if current size alignment is too big, try smaller size */ if ((start & (size - 1)) != 0) { size >>= 1; continue; } if ((end - start) >= size) { if ((size >> PAGE_SHIFT) >= min_num_pages) pdc_btlb_insert(start >> PAGE_SHIFT, __pa(start) >> PAGE_SHIFT, size >> PAGE_SHIFT, entry_info, *slot); (*slot)++; start += size; continue; } size /= 2; continue; } } void btlb_init_per_cpu(void) { unsigned long s, t, e; int slot; /* BTLBs are not available on 64-bit CPUs */ if (IS_ENABLED(CONFIG_PA20)) return; else if (pdc_btlb_info(&btlb_info) < 0) { memset(&btlb_info, 0, sizeof btlb_info); } /* insert BLTLBs for code and data segments */ s = (uintptr_t) dereference_function_descriptor(&_stext); e = (uintptr_t) dereference_function_descriptor(&_etext); t = (uintptr_t) dereference_function_descriptor(&_sdata); BUG_ON(t != e); /* code segments */ slot = 0; alloc_btlb(s, e, &slot, 0x13800000); /* sanity check */ t = (uintptr_t) dereference_function_descriptor(&_edata); e = (uintptr_t) dereference_function_descriptor(&__bss_start); BUG_ON(t != e); /* data segments */ s = (uintptr_t) dereference_function_descriptor(&_sdata); e = (uintptr_t) dereference_function_descriptor(&__bss_stop); alloc_btlb(s, e, &slot, 0x11800000); } #ifdef CONFIG_PA20 /* * Currently, all PA20 chips have 18 bit protection IDs, which is the * limiting factor (space ids are 32 bits). */ #define NR_SPACE_IDS 262144 #else /* * Currently we have a one-to-one relationship between space IDs and * protection IDs. Older parisc chips (PCXS, PCXT, PCXL, PCXL2) only * support 15 bit protection IDs, so that is the limiting factor. * PCXT' has 18 bit protection IDs, but only 16 bit spaceids, so it's * probably not worth the effort for a special case here. */ #define NR_SPACE_IDS 32768 #endif /* !CONFIG_PA20 */ #define RECYCLE_THRESHOLD (NR_SPACE_IDS / 2) #define SID_ARRAY_SIZE (NR_SPACE_IDS / (8 * sizeof(long))) static unsigned long space_id[SID_ARRAY_SIZE] = { 1 }; /* disallow space 0 */ static unsigned long dirty_space_id[SID_ARRAY_SIZE]; static unsigned long space_id_index; static unsigned long free_space_ids = NR_SPACE_IDS - 1; static unsigned long dirty_space_ids; static DEFINE_SPINLOCK(sid_lock); unsigned long alloc_sid(void) { unsigned long index; spin_lock(&sid_lock); if (free_space_ids == 0) { if (dirty_space_ids != 0) { spin_unlock(&sid_lock); flush_tlb_all(); /* flush_tlb_all() calls recycle_sids() */ spin_lock(&sid_lock); } BUG_ON(free_space_ids == 0); } free_space_ids--; index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index); space_id[BIT_WORD(index)] |= BIT_MASK(index); space_id_index = index; spin_unlock(&sid_lock); return index << SPACEID_SHIFT; } void free_sid(unsigned long spaceid) { unsigned long index = spaceid >> SPACEID_SHIFT; unsigned long *dirty_space_offset, mask; dirty_space_offset = &dirty_space_id[BIT_WORD(index)]; mask = BIT_MASK(index); spin_lock(&sid_lock); BUG_ON(*dirty_space_offset & mask); /* attempt to free space id twice */ *dirty_space_offset |= mask; dirty_space_ids++; spin_unlock(&sid_lock); } #ifdef CONFIG_SMP static void get_dirty_sids(unsigned long *ndirtyptr,unsigned long *dirty_array) { int i; /* NOTE: sid_lock must be held upon entry */ *ndirtyptr = dirty_space_ids; if (dirty_space_ids != 0) { for (i = 0; i < SID_ARRAY_SIZE; i++) { dirty_array[i] = dirty_space_id[i]; dirty_space_id[i] = 0; } dirty_space_ids = 0; } return; } static void recycle_sids(unsigned long ndirty,unsigned long *dirty_array) { int i; /* NOTE: sid_lock must be held upon entry */ if (ndirty != 0) { for (i = 0; i < SID_ARRAY_SIZE; i++) { space_id[i] ^= dirty_array[i]; } free_space_ids += ndirty; space_id_index = 0; } } #else /* CONFIG_SMP */ static void recycle_sids(void) { int i; /* NOTE: sid_lock must be held upon entry */ if (dirty_space_ids != 0) { for (i = 0; i < SID_ARRAY_SIZE; i++) { space_id[i] ^= dirty_space_id[i]; dirty_space_id[i] = 0; } free_space_ids += dirty_space_ids; dirty_space_ids = 0; space_id_index = 0; } } #endif /* * flush_tlb_all() calls recycle_sids(), since whenever the entire tlb is * purged, we can safely reuse the space ids that were released but * not flushed from the tlb. */ #ifdef CONFIG_SMP static unsigned long recycle_ndirty; static unsigned long recycle_dirty_array[SID_ARRAY_SIZE]; static unsigned int recycle_inuse; void flush_tlb_all(void) { int do_recycle; do_recycle = 0; spin_lock(&sid_lock); __inc_irq_stat(irq_tlb_count); if (dirty_space_ids > RECYCLE_THRESHOLD) { BUG_ON(recycle_inuse); /* FIXME: Use a semaphore/wait queue here */ get_dirty_sids(&recycle_ndirty,recycle_dirty_array); recycle_inuse++; do_recycle++; } spin_unlock(&sid_lock); on_each_cpu(flush_tlb_all_local, NULL, 1); if (do_recycle) { spin_lock(&sid_lock); recycle_sids(recycle_ndirty,recycle_dirty_array); recycle_inuse = 0; spin_unlock(&sid_lock); } } #else void flush_tlb_all(void) { spin_lock(&sid_lock); __inc_irq_stat(irq_tlb_count); flush_tlb_all_local(NULL); recycle_sids(); spin_unlock(&sid_lock); } #endif static const pgprot_t protection_map[16] = { [VM_NONE] = PAGE_NONE, [VM_READ] = PAGE_READONLY, [VM_WRITE] = PAGE_NONE, [VM_WRITE | VM_READ] = PAGE_READONLY, [VM_EXEC] = PAGE_EXECREAD, [VM_EXEC | VM_READ] = PAGE_EXECREAD, [VM_EXEC | VM_WRITE] = PAGE_EXECREAD, [VM_EXEC | VM_WRITE | VM_READ] = PAGE_EXECREAD, [VM_SHARED] = PAGE_NONE, [VM_SHARED | VM_READ] = PAGE_READONLY, [VM_SHARED | VM_WRITE] = PAGE_WRITEONLY, [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED, [VM_SHARED | VM_EXEC] = PAGE_EXECREAD, [VM_SHARED | VM_EXEC | VM_READ] = PAGE_EXECREAD, [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_RWX, [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_RWX }; DECLARE_VM_GET_PAGE_PROT #ifdef CONFIG_EXECMEM static struct execmem_info execmem_info __ro_after_init; struct execmem_info __init *execmem_arch_setup(void) { execmem_info = (struct execmem_info){ .ranges = { [EXECMEM_DEFAULT] = { .start = VMALLOC_START, .end = VMALLOC_END, .pgprot = PAGE_KERNEL_RWX, .alignment = 1, }, }, }; return &execmem_info; } #endif /* CONFIG_EXECMEM */