| /* | 
 |  * PowerPC64 port by Mike Corrigan and Dave Engebretsen | 
 |  *   {mikejc|engebret}@us.ibm.com | 
 |  * | 
 |  *    Copyright (c) 2000 Mike Corrigan <mikejc@us.ibm.com> | 
 |  * | 
 |  * SMP scalability work: | 
 |  *    Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM | 
 |  *  | 
 |  *    Module name: htab.c | 
 |  * | 
 |  *    Description: | 
 |  *      PowerPC Hashed Page Table functions | 
 |  * | 
 |  * 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; either version | 
 |  * 2 of the License, or (at your option) any later version. | 
 |  */ | 
 |  | 
 | #undef DEBUG | 
 | #undef DEBUG_LOW | 
 |  | 
 | #include <linux/spinlock.h> | 
 | #include <linux/errno.h> | 
 | #include <linux/sched.h> | 
 | #include <linux/proc_fs.h> | 
 | #include <linux/stat.h> | 
 | #include <linux/sysctl.h> | 
 | #include <linux/export.h> | 
 | #include <linux/ctype.h> | 
 | #include <linux/cache.h> | 
 | #include <linux/init.h> | 
 | #include <linux/signal.h> | 
 | #include <linux/memblock.h> | 
 | #include <linux/context_tracking.h> | 
 |  | 
 | #include <asm/processor.h> | 
 | #include <asm/pgtable.h> | 
 | #include <asm/mmu.h> | 
 | #include <asm/mmu_context.h> | 
 | #include <asm/page.h> | 
 | #include <asm/types.h> | 
 | #include <asm/uaccess.h> | 
 | #include <asm/machdep.h> | 
 | #include <asm/prom.h> | 
 | #include <asm/tlbflush.h> | 
 | #include <asm/io.h> | 
 | #include <asm/eeh.h> | 
 | #include <asm/tlb.h> | 
 | #include <asm/cacheflush.h> | 
 | #include <asm/cputable.h> | 
 | #include <asm/sections.h> | 
 | #include <asm/copro.h> | 
 | #include <asm/udbg.h> | 
 | #include <asm/code-patching.h> | 
 | #include <asm/fadump.h> | 
 | #include <asm/firmware.h> | 
 | #include <asm/tm.h> | 
 | #include <asm/trace.h> | 
 |  | 
 | #ifdef DEBUG | 
 | #define DBG(fmt...) udbg_printf(fmt) | 
 | #else | 
 | #define DBG(fmt...) | 
 | #endif | 
 |  | 
 | #ifdef DEBUG_LOW | 
 | #define DBG_LOW(fmt...) udbg_printf(fmt) | 
 | #else | 
 | #define DBG_LOW(fmt...) | 
 | #endif | 
 |  | 
 | #define KB (1024) | 
 | #define MB (1024*KB) | 
 | #define GB (1024L*MB) | 
 |  | 
 | /* | 
 |  * Note:  pte   --> Linux PTE | 
 |  *        HPTE  --> PowerPC Hashed Page Table Entry | 
 |  * | 
 |  * Execution context: | 
 |  *   htab_initialize is called with the MMU off (of course), but | 
 |  *   the kernel has been copied down to zero so it can directly | 
 |  *   reference global data.  At this point it is very difficult | 
 |  *   to print debug info. | 
 |  * | 
 |  */ | 
 |  | 
 | #ifdef CONFIG_U3_DART | 
 | extern unsigned long dart_tablebase; | 
 | #endif /* CONFIG_U3_DART */ | 
 |  | 
 | static unsigned long _SDR1; | 
 | struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT]; | 
 | EXPORT_SYMBOL_GPL(mmu_psize_defs); | 
 |  | 
 | struct hash_pte *htab_address; | 
 | unsigned long htab_size_bytes; | 
 | unsigned long htab_hash_mask; | 
 | EXPORT_SYMBOL_GPL(htab_hash_mask); | 
 | int mmu_linear_psize = MMU_PAGE_4K; | 
 | EXPORT_SYMBOL_GPL(mmu_linear_psize); | 
 | int mmu_virtual_psize = MMU_PAGE_4K; | 
 | int mmu_vmalloc_psize = MMU_PAGE_4K; | 
 | #ifdef CONFIG_SPARSEMEM_VMEMMAP | 
 | int mmu_vmemmap_psize = MMU_PAGE_4K; | 
 | #endif | 
 | int mmu_io_psize = MMU_PAGE_4K; | 
 | int mmu_kernel_ssize = MMU_SEGSIZE_256M; | 
 | EXPORT_SYMBOL_GPL(mmu_kernel_ssize); | 
 | int mmu_highuser_ssize = MMU_SEGSIZE_256M; | 
 | u16 mmu_slb_size = 64; | 
 | EXPORT_SYMBOL_GPL(mmu_slb_size); | 
 | #ifdef CONFIG_PPC_64K_PAGES | 
 | int mmu_ci_restrictions; | 
 | #endif | 
 | #ifdef CONFIG_DEBUG_PAGEALLOC | 
 | static u8 *linear_map_hash_slots; | 
 | static unsigned long linear_map_hash_count; | 
 | static DEFINE_SPINLOCK(linear_map_hash_lock); | 
 | #endif /* CONFIG_DEBUG_PAGEALLOC */ | 
 |  | 
 | /* There are definitions of page sizes arrays to be used when none | 
 |  * is provided by the firmware. | 
 |  */ | 
 |  | 
 | /* Pre-POWER4 CPUs (4k pages only) | 
 |  */ | 
 | static struct mmu_psize_def mmu_psize_defaults_old[] = { | 
 | 	[MMU_PAGE_4K] = { | 
 | 		.shift	= 12, | 
 | 		.sllp	= 0, | 
 | 		.penc   = {[MMU_PAGE_4K] = 0, [1 ... MMU_PAGE_COUNT - 1] = -1}, | 
 | 		.avpnm	= 0, | 
 | 		.tlbiel = 0, | 
 | 	}, | 
 | }; | 
 |  | 
 | /* POWER4, GPUL, POWER5 | 
 |  * | 
 |  * Support for 16Mb large pages | 
 |  */ | 
 | static struct mmu_psize_def mmu_psize_defaults_gp[] = { | 
 | 	[MMU_PAGE_4K] = { | 
 | 		.shift	= 12, | 
 | 		.sllp	= 0, | 
 | 		.penc   = {[MMU_PAGE_4K] = 0, [1 ... MMU_PAGE_COUNT - 1] = -1}, | 
 | 		.avpnm	= 0, | 
 | 		.tlbiel = 1, | 
 | 	}, | 
 | 	[MMU_PAGE_16M] = { | 
 | 		.shift	= 24, | 
 | 		.sllp	= SLB_VSID_L, | 
 | 		.penc   = {[0 ... MMU_PAGE_16M - 1] = -1, [MMU_PAGE_16M] = 0, | 
 | 			    [MMU_PAGE_16M + 1 ... MMU_PAGE_COUNT - 1] = -1 }, | 
 | 		.avpnm	= 0x1UL, | 
 | 		.tlbiel = 0, | 
 | 	}, | 
 | }; | 
 |  | 
 | /* | 
 |  * 'R' and 'C' update notes: | 
 |  *  - Under pHyp or KVM, the updatepp path will not set C, thus it *will* | 
 |  *     create writeable HPTEs without C set, because the hcall H_PROTECT | 
 |  *     that we use in that case will not update C | 
 |  *  - The above is however not a problem, because we also don't do that | 
 |  *     fancy "no flush" variant of eviction and we use H_REMOVE which will | 
 |  *     do the right thing and thus we don't have the race I described earlier | 
 |  * | 
 |  *    - Under bare metal,  we do have the race, so we need R and C set | 
 |  *    - We make sure R is always set and never lost | 
 |  *    - C is _PAGE_DIRTY, and *should* always be set for a writeable mapping | 
 |  */ | 
 | unsigned long htab_convert_pte_flags(unsigned long pteflags) | 
 | { | 
 | 	unsigned long rflags = 0; | 
 |  | 
 | 	/* _PAGE_EXEC -> NOEXEC */ | 
 | 	if ((pteflags & _PAGE_EXEC) == 0) | 
 | 		rflags |= HPTE_R_N; | 
 | 	/* | 
 | 	 * PPP bits: | 
 | 	 * Linux uses slb key 0 for kernel and 1 for user. | 
 | 	 * kernel RW areas are mapped with PPP=0b000 | 
 | 	 * User area is mapped with PPP=0b010 for read/write | 
 | 	 * or PPP=0b011 for read-only (including writeable but clean pages). | 
 | 	 */ | 
 | 	if (pteflags & _PAGE_PRIVILEGED) { | 
 | 		/* | 
 | 		 * Kernel read only mapped with ppp bits 0b110 | 
 | 		 */ | 
 | 		if (!(pteflags & _PAGE_WRITE)) | 
 | 			rflags |= (HPTE_R_PP0 | 0x2); | 
 | 	} else { | 
 | 		if (pteflags & _PAGE_RWX) | 
 | 			rflags |= 0x2; | 
 | 		if (!((pteflags & _PAGE_WRITE) && (pteflags & _PAGE_DIRTY))) | 
 | 			rflags |= 0x1; | 
 | 	} | 
 | 	/* | 
 | 	 * We can't allow hardware to update hpte bits. Hence always | 
 | 	 * set 'R' bit and set 'C' if it is a write fault | 
 | 	 */ | 
 | 	rflags |=  HPTE_R_R; | 
 |  | 
 | 	if (pteflags & _PAGE_DIRTY) | 
 | 		rflags |= HPTE_R_C; | 
 | 	/* | 
 | 	 * Add in WIG bits | 
 | 	 */ | 
 |  | 
 | 	if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_TOLERANT) | 
 | 		rflags |= HPTE_R_I; | 
 | 	else if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_NON_IDEMPOTENT) | 
 | 		rflags |= (HPTE_R_I | HPTE_R_G); | 
 | 	else if ((pteflags & _PAGE_CACHE_CTL) == _PAGE_SAO) | 
 | 		rflags |= (HPTE_R_W | HPTE_R_I | HPTE_R_M); | 
 | 	else | 
 | 		/* | 
 | 		 * Add memory coherence if cache inhibited is not set | 
 | 		 */ | 
 | 		rflags |= HPTE_R_M; | 
 |  | 
 | 	return rflags; | 
 | } | 
 |  | 
 | int htab_bolt_mapping(unsigned long vstart, unsigned long vend, | 
 | 		      unsigned long pstart, unsigned long prot, | 
 | 		      int psize, int ssize) | 
 | { | 
 | 	unsigned long vaddr, paddr; | 
 | 	unsigned int step, shift; | 
 | 	int ret = 0; | 
 |  | 
 | 	shift = mmu_psize_defs[psize].shift; | 
 | 	step = 1 << shift; | 
 |  | 
 | 	prot = htab_convert_pte_flags(prot); | 
 |  | 
 | 	DBG("htab_bolt_mapping(%lx..%lx -> %lx (%lx,%d,%d)\n", | 
 | 	    vstart, vend, pstart, prot, psize, ssize); | 
 |  | 
 | 	for (vaddr = vstart, paddr = pstart; vaddr < vend; | 
 | 	     vaddr += step, paddr += step) { | 
 | 		unsigned long hash, hpteg; | 
 | 		unsigned long vsid = get_kernel_vsid(vaddr, ssize); | 
 | 		unsigned long vpn  = hpt_vpn(vaddr, vsid, ssize); | 
 | 		unsigned long tprot = prot; | 
 |  | 
 | 		/* | 
 | 		 * If we hit a bad address return error. | 
 | 		 */ | 
 | 		if (!vsid) | 
 | 			return -1; | 
 | 		/* Make kernel text executable */ | 
 | 		if (overlaps_kernel_text(vaddr, vaddr + step)) | 
 | 			tprot &= ~HPTE_R_N; | 
 |  | 
 | 		/* Make kvm guest trampolines executable */ | 
 | 		if (overlaps_kvm_tmp(vaddr, vaddr + step)) | 
 | 			tprot &= ~HPTE_R_N; | 
 |  | 
 | 		/* | 
 | 		 * If relocatable, check if it overlaps interrupt vectors that | 
 | 		 * are copied down to real 0. For relocatable kernel | 
 | 		 * (e.g. kdump case) we copy interrupt vectors down to real | 
 | 		 * address 0. Mark that region as executable. This is | 
 | 		 * because on p8 system with relocation on exception feature | 
 | 		 * enabled, exceptions are raised with MMU (IR=DR=1) ON. Hence | 
 | 		 * in order to execute the interrupt handlers in virtual | 
 | 		 * mode the vector region need to be marked as executable. | 
 | 		 */ | 
 | 		if ((PHYSICAL_START > MEMORY_START) && | 
 | 			overlaps_interrupt_vector_text(vaddr, vaddr + step)) | 
 | 				tprot &= ~HPTE_R_N; | 
 |  | 
 | 		hash = hpt_hash(vpn, shift, ssize); | 
 | 		hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP); | 
 |  | 
 | 		BUG_ON(!ppc_md.hpte_insert); | 
 | 		ret = ppc_md.hpte_insert(hpteg, vpn, paddr, tprot, | 
 | 					 HPTE_V_BOLTED, psize, psize, ssize); | 
 |  | 
 | 		if (ret < 0) | 
 | 			break; | 
 |  | 
 | #ifdef CONFIG_DEBUG_PAGEALLOC | 
 | 		if (debug_pagealloc_enabled() && | 
 | 			(paddr >> PAGE_SHIFT) < linear_map_hash_count) | 
 | 			linear_map_hash_slots[paddr >> PAGE_SHIFT] = ret | 0x80; | 
 | #endif /* CONFIG_DEBUG_PAGEALLOC */ | 
 | 	} | 
 | 	return ret < 0 ? ret : 0; | 
 | } | 
 |  | 
 | int htab_remove_mapping(unsigned long vstart, unsigned long vend, | 
 | 		      int psize, int ssize) | 
 | { | 
 | 	unsigned long vaddr; | 
 | 	unsigned int step, shift; | 
 | 	int rc; | 
 | 	int ret = 0; | 
 |  | 
 | 	shift = mmu_psize_defs[psize].shift; | 
 | 	step = 1 << shift; | 
 |  | 
 | 	if (!ppc_md.hpte_removebolted) | 
 | 		return -ENODEV; | 
 |  | 
 | 	for (vaddr = vstart; vaddr < vend; vaddr += step) { | 
 | 		rc = ppc_md.hpte_removebolted(vaddr, psize, ssize); | 
 | 		if (rc == -ENOENT) { | 
 | 			ret = -ENOENT; | 
 | 			continue; | 
 | 		} | 
 | 		if (rc < 0) | 
 | 			return rc; | 
 | 	} | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static int __init htab_dt_scan_seg_sizes(unsigned long node, | 
 | 					 const char *uname, int depth, | 
 | 					 void *data) | 
 | { | 
 | 	const char *type = of_get_flat_dt_prop(node, "device_type", NULL); | 
 | 	const __be32 *prop; | 
 | 	int size = 0; | 
 |  | 
 | 	/* We are scanning "cpu" nodes only */ | 
 | 	if (type == NULL || strcmp(type, "cpu") != 0) | 
 | 		return 0; | 
 |  | 
 | 	prop = of_get_flat_dt_prop(node, "ibm,processor-segment-sizes", &size); | 
 | 	if (prop == NULL) | 
 | 		return 0; | 
 | 	for (; size >= 4; size -= 4, ++prop) { | 
 | 		if (be32_to_cpu(prop[0]) == 40) { | 
 | 			DBG("1T segment support detected\n"); | 
 | 			cur_cpu_spec->mmu_features |= MMU_FTR_1T_SEGMENT; | 
 | 			return 1; | 
 | 		} | 
 | 	} | 
 | 	cur_cpu_spec->mmu_features &= ~MMU_FTR_NO_SLBIE_B; | 
 | 	return 0; | 
 | } | 
 |  | 
 | static void __init htab_init_seg_sizes(void) | 
 | { | 
 | 	of_scan_flat_dt(htab_dt_scan_seg_sizes, NULL); | 
 | } | 
 |  | 
 | static int __init get_idx_from_shift(unsigned int shift) | 
 | { | 
 | 	int idx = -1; | 
 |  | 
 | 	switch (shift) { | 
 | 	case 0xc: | 
 | 		idx = MMU_PAGE_4K; | 
 | 		break; | 
 | 	case 0x10: | 
 | 		idx = MMU_PAGE_64K; | 
 | 		break; | 
 | 	case 0x14: | 
 | 		idx = MMU_PAGE_1M; | 
 | 		break; | 
 | 	case 0x18: | 
 | 		idx = MMU_PAGE_16M; | 
 | 		break; | 
 | 	case 0x22: | 
 | 		idx = MMU_PAGE_16G; | 
 | 		break; | 
 | 	} | 
 | 	return idx; | 
 | } | 
 |  | 
 | static int __init htab_dt_scan_page_sizes(unsigned long node, | 
 | 					  const char *uname, int depth, | 
 | 					  void *data) | 
 | { | 
 | 	const char *type = of_get_flat_dt_prop(node, "device_type", NULL); | 
 | 	const __be32 *prop; | 
 | 	int size = 0; | 
 |  | 
 | 	/* We are scanning "cpu" nodes only */ | 
 | 	if (type == NULL || strcmp(type, "cpu") != 0) | 
 | 		return 0; | 
 |  | 
 | 	prop = of_get_flat_dt_prop(node, "ibm,segment-page-sizes", &size); | 
 | 	if (!prop) | 
 | 		return 0; | 
 |  | 
 | 	pr_info("Page sizes from device-tree:\n"); | 
 | 	size /= 4; | 
 | 	cur_cpu_spec->mmu_features &= ~(MMU_FTR_16M_PAGE); | 
 | 	while(size > 0) { | 
 | 		unsigned int base_shift = be32_to_cpu(prop[0]); | 
 | 		unsigned int slbenc = be32_to_cpu(prop[1]); | 
 | 		unsigned int lpnum = be32_to_cpu(prop[2]); | 
 | 		struct mmu_psize_def *def; | 
 | 		int idx, base_idx; | 
 |  | 
 | 		size -= 3; prop += 3; | 
 | 		base_idx = get_idx_from_shift(base_shift); | 
 | 		if (base_idx < 0) { | 
 | 			/* skip the pte encoding also */ | 
 | 			prop += lpnum * 2; size -= lpnum * 2; | 
 | 			continue; | 
 | 		} | 
 | 		def = &mmu_psize_defs[base_idx]; | 
 | 		if (base_idx == MMU_PAGE_16M) | 
 | 			cur_cpu_spec->mmu_features |= MMU_FTR_16M_PAGE; | 
 |  | 
 | 		def->shift = base_shift; | 
 | 		if (base_shift <= 23) | 
 | 			def->avpnm = 0; | 
 | 		else | 
 | 			def->avpnm = (1 << (base_shift - 23)) - 1; | 
 | 		def->sllp = slbenc; | 
 | 		/* | 
 | 		 * We don't know for sure what's up with tlbiel, so | 
 | 		 * for now we only set it for 4K and 64K pages | 
 | 		 */ | 
 | 		if (base_idx == MMU_PAGE_4K || base_idx == MMU_PAGE_64K) | 
 | 			def->tlbiel = 1; | 
 | 		else | 
 | 			def->tlbiel = 0; | 
 |  | 
 | 		while (size > 0 && lpnum) { | 
 | 			unsigned int shift = be32_to_cpu(prop[0]); | 
 | 			int penc  = be32_to_cpu(prop[1]); | 
 |  | 
 | 			prop += 2; size -= 2; | 
 | 			lpnum--; | 
 |  | 
 | 			idx = get_idx_from_shift(shift); | 
 | 			if (idx < 0) | 
 | 				continue; | 
 |  | 
 | 			if (penc == -1) | 
 | 				pr_err("Invalid penc for base_shift=%d " | 
 | 				       "shift=%d\n", base_shift, shift); | 
 |  | 
 | 			def->penc[idx] = penc; | 
 | 			pr_info("base_shift=%d: shift=%d, sllp=0x%04lx," | 
 | 				" avpnm=0x%08lx, tlbiel=%d, penc=%d\n", | 
 | 				base_shift, shift, def->sllp, | 
 | 				def->avpnm, def->tlbiel, def->penc[idx]); | 
 | 		} | 
 | 	} | 
 |  | 
 | 	return 1; | 
 | } | 
 |  | 
 | #ifdef CONFIG_HUGETLB_PAGE | 
 | /* Scan for 16G memory blocks that have been set aside for huge pages | 
 |  * and reserve those blocks for 16G huge pages. | 
 |  */ | 
 | static int __init htab_dt_scan_hugepage_blocks(unsigned long node, | 
 | 					const char *uname, int depth, | 
 | 					void *data) { | 
 | 	const char *type = of_get_flat_dt_prop(node, "device_type", NULL); | 
 | 	const __be64 *addr_prop; | 
 | 	const __be32 *page_count_prop; | 
 | 	unsigned int expected_pages; | 
 | 	long unsigned int phys_addr; | 
 | 	long unsigned int block_size; | 
 |  | 
 | 	/* We are scanning "memory" nodes only */ | 
 | 	if (type == NULL || strcmp(type, "memory") != 0) | 
 | 		return 0; | 
 |  | 
 | 	/* This property is the log base 2 of the number of virtual pages that | 
 | 	 * will represent this memory block. */ | 
 | 	page_count_prop = of_get_flat_dt_prop(node, "ibm,expected#pages", NULL); | 
 | 	if (page_count_prop == NULL) | 
 | 		return 0; | 
 | 	expected_pages = (1 << be32_to_cpu(page_count_prop[0])); | 
 | 	addr_prop = of_get_flat_dt_prop(node, "reg", NULL); | 
 | 	if (addr_prop == NULL) | 
 | 		return 0; | 
 | 	phys_addr = be64_to_cpu(addr_prop[0]); | 
 | 	block_size = be64_to_cpu(addr_prop[1]); | 
 | 	if (block_size != (16 * GB)) | 
 | 		return 0; | 
 | 	printk(KERN_INFO "Huge page(16GB) memory: " | 
 | 			"addr = 0x%lX size = 0x%lX pages = %d\n", | 
 | 			phys_addr, block_size, expected_pages); | 
 | 	if (phys_addr + (16 * GB) <= memblock_end_of_DRAM()) { | 
 | 		memblock_reserve(phys_addr, block_size * expected_pages); | 
 | 		add_gpage(phys_addr, block_size, expected_pages); | 
 | 	} | 
 | 	return 0; | 
 | } | 
 | #endif /* CONFIG_HUGETLB_PAGE */ | 
 |  | 
 | static void mmu_psize_set_default_penc(void) | 
 | { | 
 | 	int bpsize, apsize; | 
 | 	for (bpsize = 0; bpsize < MMU_PAGE_COUNT; bpsize++) | 
 | 		for (apsize = 0; apsize < MMU_PAGE_COUNT; apsize++) | 
 | 			mmu_psize_defs[bpsize].penc[apsize] = -1; | 
 | } | 
 |  | 
 | #ifdef CONFIG_PPC_64K_PAGES | 
 |  | 
 | static bool might_have_hea(void) | 
 | { | 
 | 	/* | 
 | 	 * The HEA ethernet adapter requires awareness of the | 
 | 	 * GX bus. Without that awareness we can easily assume | 
 | 	 * we will never see an HEA ethernet device. | 
 | 	 */ | 
 | #ifdef CONFIG_IBMEBUS | 
 | 	return !cpu_has_feature(CPU_FTR_ARCH_207S); | 
 | #else | 
 | 	return false; | 
 | #endif | 
 | } | 
 |  | 
 | #endif /* #ifdef CONFIG_PPC_64K_PAGES */ | 
 |  | 
 | static void __init htab_init_page_sizes(void) | 
 | { | 
 | 	int rc; | 
 |  | 
 | 	/* se the invalid penc to -1 */ | 
 | 	mmu_psize_set_default_penc(); | 
 |  | 
 | 	/* Default to 4K pages only */ | 
 | 	memcpy(mmu_psize_defs, mmu_psize_defaults_old, | 
 | 	       sizeof(mmu_psize_defaults_old)); | 
 |  | 
 | 	/* | 
 | 	 * Try to find the available page sizes in the device-tree | 
 | 	 */ | 
 | 	rc = of_scan_flat_dt(htab_dt_scan_page_sizes, NULL); | 
 | 	if (rc != 0)  /* Found */ | 
 | 		goto found; | 
 |  | 
 | 	/* | 
 | 	 * Not in the device-tree, let's fallback on known size | 
 | 	 * list for 16M capable GP & GR | 
 | 	 */ | 
 | 	if (mmu_has_feature(MMU_FTR_16M_PAGE)) | 
 | 		memcpy(mmu_psize_defs, mmu_psize_defaults_gp, | 
 | 		       sizeof(mmu_psize_defaults_gp)); | 
 | found: | 
 | 	if (!debug_pagealloc_enabled()) { | 
 | 		/* | 
 | 		 * Pick a size for the linear mapping. Currently, we only | 
 | 		 * support 16M, 1M and 4K which is the default | 
 | 		 */ | 
 | 		if (mmu_psize_defs[MMU_PAGE_16M].shift) | 
 | 			mmu_linear_psize = MMU_PAGE_16M; | 
 | 		else if (mmu_psize_defs[MMU_PAGE_1M].shift) | 
 | 			mmu_linear_psize = MMU_PAGE_1M; | 
 | 	} | 
 |  | 
 | #ifdef CONFIG_PPC_64K_PAGES | 
 | 	/* | 
 | 	 * Pick a size for the ordinary pages. Default is 4K, we support | 
 | 	 * 64K for user mappings and vmalloc if supported by the processor. | 
 | 	 * We only use 64k for ioremap if the processor | 
 | 	 * (and firmware) support cache-inhibited large pages. | 
 | 	 * If not, we use 4k and set mmu_ci_restrictions so that | 
 | 	 * hash_page knows to switch processes that use cache-inhibited | 
 | 	 * mappings to 4k pages. | 
 | 	 */ | 
 | 	if (mmu_psize_defs[MMU_PAGE_64K].shift) { | 
 | 		mmu_virtual_psize = MMU_PAGE_64K; | 
 | 		mmu_vmalloc_psize = MMU_PAGE_64K; | 
 | 		if (mmu_linear_psize == MMU_PAGE_4K) | 
 | 			mmu_linear_psize = MMU_PAGE_64K; | 
 | 		if (mmu_has_feature(MMU_FTR_CI_LARGE_PAGE)) { | 
 | 			/* | 
 | 			 * When running on pSeries using 64k pages for ioremap | 
 | 			 * would stop us accessing the HEA ethernet. So if we | 
 | 			 * have the chance of ever seeing one, stay at 4k. | 
 | 			 */ | 
 | 			if (!might_have_hea() || !machine_is(pseries)) | 
 | 				mmu_io_psize = MMU_PAGE_64K; | 
 | 		} else | 
 | 			mmu_ci_restrictions = 1; | 
 | 	} | 
 | #endif /* CONFIG_PPC_64K_PAGES */ | 
 |  | 
 | #ifdef CONFIG_SPARSEMEM_VMEMMAP | 
 | 	/* We try to use 16M pages for vmemmap if that is supported | 
 | 	 * and we have at least 1G of RAM at boot | 
 | 	 */ | 
 | 	if (mmu_psize_defs[MMU_PAGE_16M].shift && | 
 | 	    memblock_phys_mem_size() >= 0x40000000) | 
 | 		mmu_vmemmap_psize = MMU_PAGE_16M; | 
 | 	else if (mmu_psize_defs[MMU_PAGE_64K].shift) | 
 | 		mmu_vmemmap_psize = MMU_PAGE_64K; | 
 | 	else | 
 | 		mmu_vmemmap_psize = MMU_PAGE_4K; | 
 | #endif /* CONFIG_SPARSEMEM_VMEMMAP */ | 
 |  | 
 | 	printk(KERN_DEBUG "Page orders: linear mapping = %d, " | 
 | 	       "virtual = %d, io = %d" | 
 | #ifdef CONFIG_SPARSEMEM_VMEMMAP | 
 | 	       ", vmemmap = %d" | 
 | #endif | 
 | 	       "\n", | 
 | 	       mmu_psize_defs[mmu_linear_psize].shift, | 
 | 	       mmu_psize_defs[mmu_virtual_psize].shift, | 
 | 	       mmu_psize_defs[mmu_io_psize].shift | 
 | #ifdef CONFIG_SPARSEMEM_VMEMMAP | 
 | 	       ,mmu_psize_defs[mmu_vmemmap_psize].shift | 
 | #endif | 
 | 	       ); | 
 |  | 
 | #ifdef CONFIG_HUGETLB_PAGE | 
 | 	/* Reserve 16G huge page memory sections for huge pages */ | 
 | 	of_scan_flat_dt(htab_dt_scan_hugepage_blocks, NULL); | 
 | #endif /* CONFIG_HUGETLB_PAGE */ | 
 | } | 
 |  | 
 | static int __init htab_dt_scan_pftsize(unsigned long node, | 
 | 				       const char *uname, int depth, | 
 | 				       void *data) | 
 | { | 
 | 	const char *type = of_get_flat_dt_prop(node, "device_type", NULL); | 
 | 	const __be32 *prop; | 
 |  | 
 | 	/* We are scanning "cpu" nodes only */ | 
 | 	if (type == NULL || strcmp(type, "cpu") != 0) | 
 | 		return 0; | 
 |  | 
 | 	prop = of_get_flat_dt_prop(node, "ibm,pft-size", NULL); | 
 | 	if (prop != NULL) { | 
 | 		/* pft_size[0] is the NUMA CEC cookie */ | 
 | 		ppc64_pft_size = be32_to_cpu(prop[1]); | 
 | 		return 1; | 
 | 	} | 
 | 	return 0; | 
 | } | 
 |  | 
 | unsigned htab_shift_for_mem_size(unsigned long mem_size) | 
 | { | 
 | 	unsigned memshift = __ilog2(mem_size); | 
 | 	unsigned pshift = mmu_psize_defs[mmu_virtual_psize].shift; | 
 | 	unsigned pteg_shift; | 
 |  | 
 | 	/* round mem_size up to next power of 2 */ | 
 | 	if ((1UL << memshift) < mem_size) | 
 | 		memshift += 1; | 
 |  | 
 | 	/* aim for 2 pages / pteg */ | 
 | 	pteg_shift = memshift - (pshift + 1); | 
 |  | 
 | 	/* | 
 | 	 * 2^11 PTEGS of 128 bytes each, ie. 2^18 bytes is the minimum htab | 
 | 	 * size permitted by the architecture. | 
 | 	 */ | 
 | 	return max(pteg_shift + 7, 18U); | 
 | } | 
 |  | 
 | static unsigned long __init htab_get_table_size(void) | 
 | { | 
 | 	/* If hash size isn't already provided by the platform, we try to | 
 | 	 * retrieve it from the device-tree. If it's not there neither, we | 
 | 	 * calculate it now based on the total RAM size | 
 | 	 */ | 
 | 	if (ppc64_pft_size == 0) | 
 | 		of_scan_flat_dt(htab_dt_scan_pftsize, NULL); | 
 | 	if (ppc64_pft_size) | 
 | 		return 1UL << ppc64_pft_size; | 
 |  | 
 | 	return 1UL << htab_shift_for_mem_size(memblock_phys_mem_size()); | 
 | } | 
 |  | 
 | #ifdef CONFIG_MEMORY_HOTPLUG | 
 | int create_section_mapping(unsigned long start, unsigned long end) | 
 | { | 
 | 	int rc = htab_bolt_mapping(start, end, __pa(start), | 
 | 				   pgprot_val(PAGE_KERNEL), mmu_linear_psize, | 
 | 				   mmu_kernel_ssize); | 
 |  | 
 | 	if (rc < 0) { | 
 | 		int rc2 = htab_remove_mapping(start, end, mmu_linear_psize, | 
 | 					      mmu_kernel_ssize); | 
 | 		BUG_ON(rc2 && (rc2 != -ENOENT)); | 
 | 	} | 
 | 	return rc; | 
 | } | 
 |  | 
 | int remove_section_mapping(unsigned long start, unsigned long end) | 
 | { | 
 | 	int rc = htab_remove_mapping(start, end, mmu_linear_psize, | 
 | 				     mmu_kernel_ssize); | 
 | 	WARN_ON(rc < 0); | 
 | 	return rc; | 
 | } | 
 | #endif /* CONFIG_MEMORY_HOTPLUG */ | 
 |  | 
 | static void __init hash_init_partition_table(phys_addr_t hash_table, | 
 | 					     unsigned long pteg_count) | 
 | { | 
 | 	unsigned long ps_field; | 
 | 	unsigned long htab_size; | 
 | 	unsigned long patb_size = 1UL << PATB_SIZE_SHIFT; | 
 |  | 
 | 	/* | 
 | 	 * slb llp encoding for the page size used in VPM real mode. | 
 | 	 * We can ignore that for lpid 0 | 
 | 	 */ | 
 | 	ps_field = 0; | 
 | 	htab_size =  __ilog2(pteg_count) - 11; | 
 |  | 
 | 	BUILD_BUG_ON_MSG((PATB_SIZE_SHIFT > 24), "Partition table size too large."); | 
 | 	partition_tb = __va(memblock_alloc_base(patb_size, patb_size, | 
 | 						MEMBLOCK_ALLOC_ANYWHERE)); | 
 |  | 
 | 	/* Initialize the Partition Table with no entries */ | 
 | 	memset((void *)partition_tb, 0, patb_size); | 
 | 	partition_tb->patb0 = cpu_to_be64(ps_field | hash_table | htab_size); | 
 | 	/* | 
 | 	 * FIXME!! This should be done via update_partition table | 
 | 	 * For now UPRT is 0 for us. | 
 | 	 */ | 
 | 	partition_tb->patb1 = 0; | 
 | 	DBG("Partition table %p\n", partition_tb); | 
 | 	/* | 
 | 	 * update partition table control register, | 
 | 	 * 64 K size. | 
 | 	 */ | 
 | 	mtspr(SPRN_PTCR, __pa(partition_tb) | (PATB_SIZE_SHIFT - 12)); | 
 |  | 
 | } | 
 |  | 
 | static void __init htab_initialize(void) | 
 | { | 
 | 	unsigned long table; | 
 | 	unsigned long pteg_count; | 
 | 	unsigned long prot; | 
 | 	unsigned long base = 0, size = 0, limit; | 
 | 	struct memblock_region *reg; | 
 |  | 
 | 	DBG(" -> htab_initialize()\n"); | 
 |  | 
 | 	/* Initialize segment sizes */ | 
 | 	htab_init_seg_sizes(); | 
 |  | 
 | 	/* Initialize page sizes */ | 
 | 	htab_init_page_sizes(); | 
 |  | 
 | 	if (mmu_has_feature(MMU_FTR_1T_SEGMENT)) { | 
 | 		mmu_kernel_ssize = MMU_SEGSIZE_1T; | 
 | 		mmu_highuser_ssize = MMU_SEGSIZE_1T; | 
 | 		printk(KERN_INFO "Using 1TB segments\n"); | 
 | 	} | 
 |  | 
 | 	/* | 
 | 	 * Calculate the required size of the htab.  We want the number of | 
 | 	 * PTEGs to equal one half the number of real pages. | 
 | 	 */  | 
 | 	htab_size_bytes = htab_get_table_size(); | 
 | 	pteg_count = htab_size_bytes >> 7; | 
 |  | 
 | 	htab_hash_mask = pteg_count - 1; | 
 |  | 
 | 	if (firmware_has_feature(FW_FEATURE_LPAR)) { | 
 | 		/* Using a hypervisor which owns the htab */ | 
 | 		htab_address = NULL; | 
 | 		_SDR1 = 0;  | 
 | #ifdef CONFIG_FA_DUMP | 
 | 		/* | 
 | 		 * If firmware assisted dump is active firmware preserves | 
 | 		 * the contents of htab along with entire partition memory. | 
 | 		 * Clear the htab if firmware assisted dump is active so | 
 | 		 * that we dont end up using old mappings. | 
 | 		 */ | 
 | 		if (is_fadump_active() && ppc_md.hpte_clear_all) | 
 | 			ppc_md.hpte_clear_all(); | 
 | #endif | 
 | 	} else { | 
 | 		/* Find storage for the HPT.  Must be contiguous in | 
 | 		 * the absolute address space. On cell we want it to be | 
 | 		 * in the first 2 Gig so we can use it for IOMMU hacks. | 
 | 		 */ | 
 | 		if (machine_is(cell)) | 
 | 			limit = 0x80000000; | 
 | 		else | 
 | 			limit = MEMBLOCK_ALLOC_ANYWHERE; | 
 |  | 
 | 		table = memblock_alloc_base(htab_size_bytes, htab_size_bytes, limit); | 
 |  | 
 | 		DBG("Hash table allocated at %lx, size: %lx\n", table, | 
 | 		    htab_size_bytes); | 
 |  | 
 | 		htab_address = __va(table); | 
 |  | 
 | 		/* htab absolute addr + encoded htabsize */ | 
 | 		_SDR1 = table + __ilog2(pteg_count) - 11; | 
 |  | 
 | 		/* Initialize the HPT with no entries */ | 
 | 		memset((void *)table, 0, htab_size_bytes); | 
 |  | 
 | 		if (!cpu_has_feature(CPU_FTR_ARCH_300)) | 
 | 			/* Set SDR1 */ | 
 | 			mtspr(SPRN_SDR1, _SDR1); | 
 | 		else | 
 | 			hash_init_partition_table(table, pteg_count); | 
 | 	} | 
 |  | 
 | 	prot = pgprot_val(PAGE_KERNEL); | 
 |  | 
 | #ifdef CONFIG_DEBUG_PAGEALLOC | 
 | 	if (debug_pagealloc_enabled()) { | 
 | 		linear_map_hash_count = memblock_end_of_DRAM() >> PAGE_SHIFT; | 
 | 		linear_map_hash_slots = __va(memblock_alloc_base( | 
 | 				linear_map_hash_count, 1, ppc64_rma_size)); | 
 | 		memset(linear_map_hash_slots, 0, linear_map_hash_count); | 
 | 	} | 
 | #endif /* CONFIG_DEBUG_PAGEALLOC */ | 
 |  | 
 | 	/* On U3 based machines, we need to reserve the DART area and | 
 | 	 * _NOT_ map it to avoid cache paradoxes as it's remapped non | 
 | 	 * cacheable later on | 
 | 	 */ | 
 |  | 
 | 	/* create bolted the linear mapping in the hash table */ | 
 | 	for_each_memblock(memory, reg) { | 
 | 		base = (unsigned long)__va(reg->base); | 
 | 		size = reg->size; | 
 |  | 
 | 		DBG("creating mapping for region: %lx..%lx (prot: %lx)\n", | 
 | 		    base, size, prot); | 
 |  | 
 | #ifdef CONFIG_U3_DART | 
 | 		/* Do not map the DART space. Fortunately, it will be aligned | 
 | 		 * in such a way that it will not cross two memblock regions and | 
 | 		 * will fit within a single 16Mb page. | 
 | 		 * The DART space is assumed to be a full 16Mb region even if | 
 | 		 * we only use 2Mb of that space. We will use more of it later | 
 | 		 * for AGP GART. We have to use a full 16Mb large page. | 
 | 		 */ | 
 | 		DBG("DART base: %lx\n", dart_tablebase); | 
 |  | 
 | 		if (dart_tablebase != 0 && dart_tablebase >= base | 
 | 		    && dart_tablebase < (base + size)) { | 
 | 			unsigned long dart_table_end = dart_tablebase + 16 * MB; | 
 | 			if (base != dart_tablebase) | 
 | 				BUG_ON(htab_bolt_mapping(base, dart_tablebase, | 
 | 							__pa(base), prot, | 
 | 							mmu_linear_psize, | 
 | 							mmu_kernel_ssize)); | 
 | 			if ((base + size) > dart_table_end) | 
 | 				BUG_ON(htab_bolt_mapping(dart_tablebase+16*MB, | 
 | 							base + size, | 
 | 							__pa(dart_table_end), | 
 | 							 prot, | 
 | 							 mmu_linear_psize, | 
 | 							 mmu_kernel_ssize)); | 
 | 			continue; | 
 | 		} | 
 | #endif /* CONFIG_U3_DART */ | 
 | 		BUG_ON(htab_bolt_mapping(base, base + size, __pa(base), | 
 | 				prot, mmu_linear_psize, mmu_kernel_ssize)); | 
 | 	} | 
 | 	memblock_set_current_limit(MEMBLOCK_ALLOC_ANYWHERE); | 
 |  | 
 | 	/* | 
 | 	 * If we have a memory_limit and we've allocated TCEs then we need to | 
 | 	 * explicitly map the TCE area at the top of RAM. We also cope with the | 
 | 	 * case that the TCEs start below memory_limit. | 
 | 	 * tce_alloc_start/end are 16MB aligned so the mapping should work | 
 | 	 * for either 4K or 16MB pages. | 
 | 	 */ | 
 | 	if (tce_alloc_start) { | 
 | 		tce_alloc_start = (unsigned long)__va(tce_alloc_start); | 
 | 		tce_alloc_end = (unsigned long)__va(tce_alloc_end); | 
 |  | 
 | 		if (base + size >= tce_alloc_start) | 
 | 			tce_alloc_start = base + size + 1; | 
 |  | 
 | 		BUG_ON(htab_bolt_mapping(tce_alloc_start, tce_alloc_end, | 
 | 					 __pa(tce_alloc_start), prot, | 
 | 					 mmu_linear_psize, mmu_kernel_ssize)); | 
 | 	} | 
 |  | 
 |  | 
 | 	DBG(" <- htab_initialize()\n"); | 
 | } | 
 | #undef KB | 
 | #undef MB | 
 |  | 
 | void __init hash__early_init_mmu(void) | 
 | { | 
 | 	/* | 
 | 	 * initialize page table size | 
 | 	 */ | 
 | 	__pte_frag_nr = H_PTE_FRAG_NR; | 
 | 	__pte_frag_size_shift = H_PTE_FRAG_SIZE_SHIFT; | 
 |  | 
 | 	__pte_index_size = H_PTE_INDEX_SIZE; | 
 | 	__pmd_index_size = H_PMD_INDEX_SIZE; | 
 | 	__pud_index_size = H_PUD_INDEX_SIZE; | 
 | 	__pgd_index_size = H_PGD_INDEX_SIZE; | 
 | 	__pmd_cache_index = H_PMD_CACHE_INDEX; | 
 | 	__pte_table_size = H_PTE_TABLE_SIZE; | 
 | 	__pmd_table_size = H_PMD_TABLE_SIZE; | 
 | 	__pud_table_size = H_PUD_TABLE_SIZE; | 
 | 	__pgd_table_size = H_PGD_TABLE_SIZE; | 
 | 	/* | 
 | 	 * 4k use hugepd format, so for hash set then to | 
 | 	 * zero | 
 | 	 */ | 
 | 	__pmd_val_bits = 0; | 
 | 	__pud_val_bits = 0; | 
 | 	__pgd_val_bits = 0; | 
 |  | 
 | 	__kernel_virt_start = H_KERN_VIRT_START; | 
 | 	__kernel_virt_size = H_KERN_VIRT_SIZE; | 
 | 	__vmalloc_start = H_VMALLOC_START; | 
 | 	__vmalloc_end = H_VMALLOC_END; | 
 | 	vmemmap = (struct page *)H_VMEMMAP_BASE; | 
 | 	ioremap_bot = IOREMAP_BASE; | 
 |  | 
 | #ifdef CONFIG_PCI | 
 | 	pci_io_base = ISA_IO_BASE; | 
 | #endif | 
 |  | 
 | 	/* Initialize the MMU Hash table and create the linear mapping | 
 | 	 * of memory. Has to be done before SLB initialization as this is | 
 | 	 * currently where the page size encoding is obtained. | 
 | 	 */ | 
 | 	htab_initialize(); | 
 |  | 
 | 	/* Initialize SLB management */ | 
 | 	slb_initialize(); | 
 | } | 
 |  | 
 | #ifdef CONFIG_SMP | 
 | void hash__early_init_mmu_secondary(void) | 
 | { | 
 | 	/* Initialize hash table for that CPU */ | 
 | 	if (!firmware_has_feature(FW_FEATURE_LPAR)) { | 
 | 		if (!cpu_has_feature(CPU_FTR_ARCH_300)) | 
 | 			mtspr(SPRN_SDR1, _SDR1); | 
 | 		else | 
 | 			mtspr(SPRN_PTCR, | 
 | 			      __pa(partition_tb) | (PATB_SIZE_SHIFT - 12)); | 
 | 	} | 
 | 	/* Initialize SLB */ | 
 | 	slb_initialize(); | 
 | } | 
 | #endif /* CONFIG_SMP */ | 
 |  | 
 | /* | 
 |  * Called by asm hashtable.S for doing lazy icache flush | 
 |  */ | 
 | unsigned int hash_page_do_lazy_icache(unsigned int pp, pte_t pte, int trap) | 
 | { | 
 | 	struct page *page; | 
 |  | 
 | 	if (!pfn_valid(pte_pfn(pte))) | 
 | 		return pp; | 
 |  | 
 | 	page = pte_page(pte); | 
 |  | 
 | 	/* page is dirty */ | 
 | 	if (!test_bit(PG_arch_1, &page->flags) && !PageReserved(page)) { | 
 | 		if (trap == 0x400) { | 
 | 			flush_dcache_icache_page(page); | 
 | 			set_bit(PG_arch_1, &page->flags); | 
 | 		} else | 
 | 			pp |= HPTE_R_N; | 
 | 	} | 
 | 	return pp; | 
 | } | 
 |  | 
 | #ifdef CONFIG_PPC_MM_SLICES | 
 | static unsigned int get_paca_psize(unsigned long addr) | 
 | { | 
 | 	u64 lpsizes; | 
 | 	unsigned char *hpsizes; | 
 | 	unsigned long index, mask_index; | 
 |  | 
 | 	if (addr < SLICE_LOW_TOP) { | 
 | 		lpsizes = get_paca()->mm_ctx_low_slices_psize; | 
 | 		index = GET_LOW_SLICE_INDEX(addr); | 
 | 		return (lpsizes >> (index * 4)) & 0xF; | 
 | 	} | 
 | 	hpsizes = get_paca()->mm_ctx_high_slices_psize; | 
 | 	index = GET_HIGH_SLICE_INDEX(addr); | 
 | 	mask_index = index & 0x1; | 
 | 	return (hpsizes[index >> 1] >> (mask_index * 4)) & 0xF; | 
 | } | 
 |  | 
 | #else | 
 | unsigned int get_paca_psize(unsigned long addr) | 
 | { | 
 | 	return get_paca()->mm_ctx_user_psize; | 
 | } | 
 | #endif | 
 |  | 
 | /* | 
 |  * Demote a segment to using 4k pages. | 
 |  * For now this makes the whole process use 4k pages. | 
 |  */ | 
 | #ifdef CONFIG_PPC_64K_PAGES | 
 | void demote_segment_4k(struct mm_struct *mm, unsigned long addr) | 
 | { | 
 | 	if (get_slice_psize(mm, addr) == MMU_PAGE_4K) | 
 | 		return; | 
 | 	slice_set_range_psize(mm, addr, 1, MMU_PAGE_4K); | 
 | 	copro_flush_all_slbs(mm); | 
 | 	if ((get_paca_psize(addr) != MMU_PAGE_4K) && (current->mm == mm)) { | 
 |  | 
 | 		copy_mm_to_paca(&mm->context); | 
 | 		slb_flush_and_rebolt(); | 
 | 	} | 
 | } | 
 | #endif /* CONFIG_PPC_64K_PAGES */ | 
 |  | 
 | #ifdef CONFIG_PPC_SUBPAGE_PROT | 
 | /* | 
 |  * This looks up a 2-bit protection code for a 4k subpage of a 64k page. | 
 |  * Userspace sets the subpage permissions using the subpage_prot system call. | 
 |  * | 
 |  * Result is 0: full permissions, _PAGE_RW: read-only, | 
 |  * _PAGE_RWX: no access. | 
 |  */ | 
 | static int subpage_protection(struct mm_struct *mm, unsigned long ea) | 
 | { | 
 | 	struct subpage_prot_table *spt = &mm->context.spt; | 
 | 	u32 spp = 0; | 
 | 	u32 **sbpm, *sbpp; | 
 |  | 
 | 	if (ea >= spt->maxaddr) | 
 | 		return 0; | 
 | 	if (ea < 0x100000000UL) { | 
 | 		/* addresses below 4GB use spt->low_prot */ | 
 | 		sbpm = spt->low_prot; | 
 | 	} else { | 
 | 		sbpm = spt->protptrs[ea >> SBP_L3_SHIFT]; | 
 | 		if (!sbpm) | 
 | 			return 0; | 
 | 	} | 
 | 	sbpp = sbpm[(ea >> SBP_L2_SHIFT) & (SBP_L2_COUNT - 1)]; | 
 | 	if (!sbpp) | 
 | 		return 0; | 
 | 	spp = sbpp[(ea >> PAGE_SHIFT) & (SBP_L1_COUNT - 1)]; | 
 |  | 
 | 	/* extract 2-bit bitfield for this 4k subpage */ | 
 | 	spp >>= 30 - 2 * ((ea >> 12) & 0xf); | 
 |  | 
 | 	/* | 
 | 	 * 0 -> full premission | 
 | 	 * 1 -> Read only | 
 | 	 * 2 -> no access. | 
 | 	 * We return the flag that need to be cleared. | 
 | 	 */ | 
 | 	spp = ((spp & 2) ? _PAGE_RWX : 0) | ((spp & 1) ? _PAGE_WRITE : 0); | 
 | 	return spp; | 
 | } | 
 |  | 
 | #else /* CONFIG_PPC_SUBPAGE_PROT */ | 
 | static inline int subpage_protection(struct mm_struct *mm, unsigned long ea) | 
 | { | 
 | 	return 0; | 
 | } | 
 | #endif | 
 |  | 
 | void hash_failure_debug(unsigned long ea, unsigned long access, | 
 | 			unsigned long vsid, unsigned long trap, | 
 | 			int ssize, int psize, int lpsize, unsigned long pte) | 
 | { | 
 | 	if (!printk_ratelimit()) | 
 | 		return; | 
 | 	pr_info("mm: Hashing failure ! EA=0x%lx access=0x%lx current=%s\n", | 
 | 		ea, access, current->comm); | 
 | 	pr_info("    trap=0x%lx vsid=0x%lx ssize=%d base psize=%d psize %d pte=0x%lx\n", | 
 | 		trap, vsid, ssize, psize, lpsize, pte); | 
 | } | 
 |  | 
 | static void check_paca_psize(unsigned long ea, struct mm_struct *mm, | 
 | 			     int psize, bool user_region) | 
 | { | 
 | 	if (user_region) { | 
 | 		if (psize != get_paca_psize(ea)) { | 
 | 			copy_mm_to_paca(&mm->context); | 
 | 			slb_flush_and_rebolt(); | 
 | 		} | 
 | 	} else if (get_paca()->vmalloc_sllp != | 
 | 		   mmu_psize_defs[mmu_vmalloc_psize].sllp) { | 
 | 		get_paca()->vmalloc_sllp = | 
 | 			mmu_psize_defs[mmu_vmalloc_psize].sllp; | 
 | 		slb_vmalloc_update(); | 
 | 	} | 
 | } | 
 |  | 
 | /* Result code is: | 
 |  *  0 - handled | 
 |  *  1 - normal page fault | 
 |  * -1 - critical hash insertion error | 
 |  * -2 - access not permitted by subpage protection mechanism | 
 |  */ | 
 | int hash_page_mm(struct mm_struct *mm, unsigned long ea, | 
 | 		 unsigned long access, unsigned long trap, | 
 | 		 unsigned long flags) | 
 | { | 
 | 	bool is_thp; | 
 | 	enum ctx_state prev_state = exception_enter(); | 
 | 	pgd_t *pgdir; | 
 | 	unsigned long vsid; | 
 | 	pte_t *ptep; | 
 | 	unsigned hugeshift; | 
 | 	const struct cpumask *tmp; | 
 | 	int rc, user_region = 0; | 
 | 	int psize, ssize; | 
 |  | 
 | 	DBG_LOW("hash_page(ea=%016lx, access=%lx, trap=%lx\n", | 
 | 		ea, access, trap); | 
 | 	trace_hash_fault(ea, access, trap); | 
 |  | 
 | 	/* Get region & vsid */ | 
 |  	switch (REGION_ID(ea)) { | 
 | 	case USER_REGION_ID: | 
 | 		user_region = 1; | 
 | 		if (! mm) { | 
 | 			DBG_LOW(" user region with no mm !\n"); | 
 | 			rc = 1; | 
 | 			goto bail; | 
 | 		} | 
 | 		psize = get_slice_psize(mm, ea); | 
 | 		ssize = user_segment_size(ea); | 
 | 		vsid = get_vsid(mm->context.id, ea, ssize); | 
 | 		break; | 
 | 	case VMALLOC_REGION_ID: | 
 | 		vsid = get_kernel_vsid(ea, mmu_kernel_ssize); | 
 | 		if (ea < VMALLOC_END) | 
 | 			psize = mmu_vmalloc_psize; | 
 | 		else | 
 | 			psize = mmu_io_psize; | 
 | 		ssize = mmu_kernel_ssize; | 
 | 		break; | 
 | 	default: | 
 | 		/* Not a valid range | 
 | 		 * Send the problem up to do_page_fault  | 
 | 		 */ | 
 | 		rc = 1; | 
 | 		goto bail; | 
 | 	} | 
 | 	DBG_LOW(" mm=%p, mm->pgdir=%p, vsid=%016lx\n", mm, mm->pgd, vsid); | 
 |  | 
 | 	/* Bad address. */ | 
 | 	if (!vsid) { | 
 | 		DBG_LOW("Bad address!\n"); | 
 | 		rc = 1; | 
 | 		goto bail; | 
 | 	} | 
 | 	/* Get pgdir */ | 
 | 	pgdir = mm->pgd; | 
 | 	if (pgdir == NULL) { | 
 | 		rc = 1; | 
 | 		goto bail; | 
 | 	} | 
 |  | 
 | 	/* Check CPU locality */ | 
 | 	tmp = cpumask_of(smp_processor_id()); | 
 | 	if (user_region && cpumask_equal(mm_cpumask(mm), tmp)) | 
 | 		flags |= HPTE_LOCAL_UPDATE; | 
 |  | 
 | #ifndef CONFIG_PPC_64K_PAGES | 
 | 	/* If we use 4K pages and our psize is not 4K, then we might | 
 | 	 * be hitting a special driver mapping, and need to align the | 
 | 	 * address before we fetch the PTE. | 
 | 	 * | 
 | 	 * It could also be a hugepage mapping, in which case this is | 
 | 	 * not necessary, but it's not harmful, either. | 
 | 	 */ | 
 | 	if (psize != MMU_PAGE_4K) | 
 | 		ea &= ~((1ul << mmu_psize_defs[psize].shift) - 1); | 
 | #endif /* CONFIG_PPC_64K_PAGES */ | 
 |  | 
 | 	/* Get PTE and page size from page tables */ | 
 | 	ptep = __find_linux_pte_or_hugepte(pgdir, ea, &is_thp, &hugeshift); | 
 | 	if (ptep == NULL || !pte_present(*ptep)) { | 
 | 		DBG_LOW(" no PTE !\n"); | 
 | 		rc = 1; | 
 | 		goto bail; | 
 | 	} | 
 |  | 
 | 	/* Add _PAGE_PRESENT to the required access perm */ | 
 | 	access |= _PAGE_PRESENT; | 
 |  | 
 | 	/* Pre-check access permissions (will be re-checked atomically | 
 | 	 * in __hash_page_XX but this pre-check is a fast path | 
 | 	 */ | 
 | 	if (!check_pte_access(access, pte_val(*ptep))) { | 
 | 		DBG_LOW(" no access !\n"); | 
 | 		rc = 1; | 
 | 		goto bail; | 
 | 	} | 
 |  | 
 | 	if (hugeshift) { | 
 | 		if (is_thp) | 
 | 			rc = __hash_page_thp(ea, access, vsid, (pmd_t *)ptep, | 
 | 					     trap, flags, ssize, psize); | 
 | #ifdef CONFIG_HUGETLB_PAGE | 
 | 		else | 
 | 			rc = __hash_page_huge(ea, access, vsid, ptep, trap, | 
 | 					      flags, ssize, hugeshift, psize); | 
 | #else | 
 | 		else { | 
 | 			/* | 
 | 			 * if we have hugeshift, and is not transhuge with | 
 | 			 * hugetlb disabled, something is really wrong. | 
 | 			 */ | 
 | 			rc = 1; | 
 | 			WARN_ON(1); | 
 | 		} | 
 | #endif | 
 | 		if (current->mm == mm) | 
 | 			check_paca_psize(ea, mm, psize, user_region); | 
 |  | 
 | 		goto bail; | 
 | 	} | 
 |  | 
 | #ifndef CONFIG_PPC_64K_PAGES | 
 | 	DBG_LOW(" i-pte: %016lx\n", pte_val(*ptep)); | 
 | #else | 
 | 	DBG_LOW(" i-pte: %016lx %016lx\n", pte_val(*ptep), | 
 | 		pte_val(*(ptep + PTRS_PER_PTE))); | 
 | #endif | 
 | 	/* Do actual hashing */ | 
 | #ifdef CONFIG_PPC_64K_PAGES | 
 | 	/* If H_PAGE_4K_PFN is set, make sure this is a 4k segment */ | 
 | 	if ((pte_val(*ptep) & H_PAGE_4K_PFN) && psize == MMU_PAGE_64K) { | 
 | 		demote_segment_4k(mm, ea); | 
 | 		psize = MMU_PAGE_4K; | 
 | 	} | 
 |  | 
 | 	/* If this PTE is non-cacheable and we have restrictions on | 
 | 	 * using non cacheable large pages, then we switch to 4k | 
 | 	 */ | 
 | 	if (mmu_ci_restrictions && psize == MMU_PAGE_64K && pte_ci(*ptep)) { | 
 | 		if (user_region) { | 
 | 			demote_segment_4k(mm, ea); | 
 | 			psize = MMU_PAGE_4K; | 
 | 		} else if (ea < VMALLOC_END) { | 
 | 			/* | 
 | 			 * some driver did a non-cacheable mapping | 
 | 			 * in vmalloc space, so switch vmalloc | 
 | 			 * to 4k pages | 
 | 			 */ | 
 | 			printk(KERN_ALERT "Reducing vmalloc segment " | 
 | 			       "to 4kB pages because of " | 
 | 			       "non-cacheable mapping\n"); | 
 | 			psize = mmu_vmalloc_psize = MMU_PAGE_4K; | 
 | 			copro_flush_all_slbs(mm); | 
 | 		} | 
 | 	} | 
 |  | 
 | #endif /* CONFIG_PPC_64K_PAGES */ | 
 |  | 
 | 	if (current->mm == mm) | 
 | 		check_paca_psize(ea, mm, psize, user_region); | 
 |  | 
 | #ifdef CONFIG_PPC_64K_PAGES | 
 | 	if (psize == MMU_PAGE_64K) | 
 | 		rc = __hash_page_64K(ea, access, vsid, ptep, trap, | 
 | 				     flags, ssize); | 
 | 	else | 
 | #endif /* CONFIG_PPC_64K_PAGES */ | 
 | 	{ | 
 | 		int spp = subpage_protection(mm, ea); | 
 | 		if (access & spp) | 
 | 			rc = -2; | 
 | 		else | 
 | 			rc = __hash_page_4K(ea, access, vsid, ptep, trap, | 
 | 					    flags, ssize, spp); | 
 | 	} | 
 |  | 
 | 	/* Dump some info in case of hash insertion failure, they should | 
 | 	 * never happen so it is really useful to know if/when they do | 
 | 	 */ | 
 | 	if (rc == -1) | 
 | 		hash_failure_debug(ea, access, vsid, trap, ssize, psize, | 
 | 				   psize, pte_val(*ptep)); | 
 | #ifndef CONFIG_PPC_64K_PAGES | 
 | 	DBG_LOW(" o-pte: %016lx\n", pte_val(*ptep)); | 
 | #else | 
 | 	DBG_LOW(" o-pte: %016lx %016lx\n", pte_val(*ptep), | 
 | 		pte_val(*(ptep + PTRS_PER_PTE))); | 
 | #endif | 
 | 	DBG_LOW(" -> rc=%d\n", rc); | 
 |  | 
 | bail: | 
 | 	exception_exit(prev_state); | 
 | 	return rc; | 
 | } | 
 | EXPORT_SYMBOL_GPL(hash_page_mm); | 
 |  | 
 | int hash_page(unsigned long ea, unsigned long access, unsigned long trap, | 
 | 	      unsigned long dsisr) | 
 | { | 
 | 	unsigned long flags = 0; | 
 | 	struct mm_struct *mm = current->mm; | 
 |  | 
 | 	if (REGION_ID(ea) == VMALLOC_REGION_ID) | 
 | 		mm = &init_mm; | 
 |  | 
 | 	if (dsisr & DSISR_NOHPTE) | 
 | 		flags |= HPTE_NOHPTE_UPDATE; | 
 |  | 
 | 	return hash_page_mm(mm, ea, access, trap, flags); | 
 | } | 
 | EXPORT_SYMBOL_GPL(hash_page); | 
 |  | 
 | int __hash_page(unsigned long ea, unsigned long msr, unsigned long trap, | 
 | 		unsigned long dsisr) | 
 | { | 
 | 	unsigned long access = _PAGE_PRESENT | _PAGE_READ; | 
 | 	unsigned long flags = 0; | 
 | 	struct mm_struct *mm = current->mm; | 
 |  | 
 | 	if (REGION_ID(ea) == VMALLOC_REGION_ID) | 
 | 		mm = &init_mm; | 
 |  | 
 | 	if (dsisr & DSISR_NOHPTE) | 
 | 		flags |= HPTE_NOHPTE_UPDATE; | 
 |  | 
 | 	if (dsisr & DSISR_ISSTORE) | 
 | 		access |= _PAGE_WRITE; | 
 | 	/* | 
 | 	 * We set _PAGE_PRIVILEGED only when | 
 | 	 * kernel mode access kernel space. | 
 | 	 * | 
 | 	 * _PAGE_PRIVILEGED is NOT set | 
 | 	 * 1) when kernel mode access user space | 
 | 	 * 2) user space access kernel space. | 
 | 	 */ | 
 | 	access |= _PAGE_PRIVILEGED; | 
 | 	if ((msr & MSR_PR) || (REGION_ID(ea) == USER_REGION_ID)) | 
 | 		access &= ~_PAGE_PRIVILEGED; | 
 |  | 
 | 	if (trap == 0x400) | 
 | 		access |= _PAGE_EXEC; | 
 |  | 
 | 	return hash_page_mm(mm, ea, access, trap, flags); | 
 | } | 
 |  | 
 | #ifdef CONFIG_PPC_MM_SLICES | 
 | static bool should_hash_preload(struct mm_struct *mm, unsigned long ea) | 
 | { | 
 | 	int psize = get_slice_psize(mm, ea); | 
 |  | 
 | 	/* We only prefault standard pages for now */ | 
 | 	if (unlikely(psize != mm->context.user_psize)) | 
 | 		return false; | 
 |  | 
 | 	/* | 
 | 	 * Don't prefault if subpage protection is enabled for the EA. | 
 | 	 */ | 
 | 	if (unlikely((psize == MMU_PAGE_4K) && subpage_protection(mm, ea))) | 
 | 		return false; | 
 |  | 
 | 	return true; | 
 | } | 
 | #else | 
 | static bool should_hash_preload(struct mm_struct *mm, unsigned long ea) | 
 | { | 
 | 	return true; | 
 | } | 
 | #endif | 
 |  | 
 | void hash_preload(struct mm_struct *mm, unsigned long ea, | 
 | 		  unsigned long access, unsigned long trap) | 
 | { | 
 | 	int hugepage_shift; | 
 | 	unsigned long vsid; | 
 | 	pgd_t *pgdir; | 
 | 	pte_t *ptep; | 
 | 	unsigned long flags; | 
 | 	int rc, ssize, update_flags = 0; | 
 |  | 
 | 	BUG_ON(REGION_ID(ea) != USER_REGION_ID); | 
 |  | 
 | 	if (!should_hash_preload(mm, ea)) | 
 | 		return; | 
 |  | 
 | 	DBG_LOW("hash_preload(mm=%p, mm->pgdir=%p, ea=%016lx, access=%lx," | 
 | 		" trap=%lx\n", mm, mm->pgd, ea, access, trap); | 
 |  | 
 | 	/* Get Linux PTE if available */ | 
 | 	pgdir = mm->pgd; | 
 | 	if (pgdir == NULL) | 
 | 		return; | 
 |  | 
 | 	/* Get VSID */ | 
 | 	ssize = user_segment_size(ea); | 
 | 	vsid = get_vsid(mm->context.id, ea, ssize); | 
 | 	if (!vsid) | 
 | 		return; | 
 | 	/* | 
 | 	 * Hash doesn't like irqs. Walking linux page table with irq disabled | 
 | 	 * saves us from holding multiple locks. | 
 | 	 */ | 
 | 	local_irq_save(flags); | 
 |  | 
 | 	/* | 
 | 	 * THP pages use update_mmu_cache_pmd. We don't do | 
 | 	 * hash preload there. Hence can ignore THP here | 
 | 	 */ | 
 | 	ptep = find_linux_pte_or_hugepte(pgdir, ea, NULL, &hugepage_shift); | 
 | 	if (!ptep) | 
 | 		goto out_exit; | 
 |  | 
 | 	WARN_ON(hugepage_shift); | 
 | #ifdef CONFIG_PPC_64K_PAGES | 
 | 	/* If either H_PAGE_4K_PFN or cache inhibited is set (and we are on | 
 | 	 * a 64K kernel), then we don't preload, hash_page() will take | 
 | 	 * care of it once we actually try to access the page. | 
 | 	 * That way we don't have to duplicate all of the logic for segment | 
 | 	 * page size demotion here | 
 | 	 */ | 
 | 	if ((pte_val(*ptep) & H_PAGE_4K_PFN) || pte_ci(*ptep)) | 
 | 		goto out_exit; | 
 | #endif /* CONFIG_PPC_64K_PAGES */ | 
 |  | 
 | 	/* Is that local to this CPU ? */ | 
 | 	if (cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id()))) | 
 | 		update_flags |= HPTE_LOCAL_UPDATE; | 
 |  | 
 | 	/* Hash it in */ | 
 | #ifdef CONFIG_PPC_64K_PAGES | 
 | 	if (mm->context.user_psize == MMU_PAGE_64K) | 
 | 		rc = __hash_page_64K(ea, access, vsid, ptep, trap, | 
 | 				     update_flags, ssize); | 
 | 	else | 
 | #endif /* CONFIG_PPC_64K_PAGES */ | 
 | 		rc = __hash_page_4K(ea, access, vsid, ptep, trap, update_flags, | 
 | 				    ssize, subpage_protection(mm, ea)); | 
 |  | 
 | 	/* Dump some info in case of hash insertion failure, they should | 
 | 	 * never happen so it is really useful to know if/when they do | 
 | 	 */ | 
 | 	if (rc == -1) | 
 | 		hash_failure_debug(ea, access, vsid, trap, ssize, | 
 | 				   mm->context.user_psize, | 
 | 				   mm->context.user_psize, | 
 | 				   pte_val(*ptep)); | 
 | out_exit: | 
 | 	local_irq_restore(flags); | 
 | } | 
 |  | 
 | /* WARNING: This is called from hash_low_64.S, if you change this prototype, | 
 |  *          do not forget to update the assembly call site ! | 
 |  */ | 
 | void flush_hash_page(unsigned long vpn, real_pte_t pte, int psize, int ssize, | 
 | 		     unsigned long flags) | 
 | { | 
 | 	unsigned long hash, index, shift, hidx, slot; | 
 | 	int local = flags & HPTE_LOCAL_UPDATE; | 
 |  | 
 | 	DBG_LOW("flush_hash_page(vpn=%016lx)\n", vpn); | 
 | 	pte_iterate_hashed_subpages(pte, psize, vpn, index, shift) { | 
 | 		hash = hpt_hash(vpn, shift, ssize); | 
 | 		hidx = __rpte_to_hidx(pte, index); | 
 | 		if (hidx & _PTEIDX_SECONDARY) | 
 | 			hash = ~hash; | 
 | 		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP; | 
 | 		slot += hidx & _PTEIDX_GROUP_IX; | 
 | 		DBG_LOW(" sub %ld: hash=%lx, hidx=%lx\n", index, slot, hidx); | 
 | 		/* | 
 | 		 * We use same base page size and actual psize, because we don't | 
 | 		 * use these functions for hugepage | 
 | 		 */ | 
 | 		ppc_md.hpte_invalidate(slot, vpn, psize, psize, ssize, local); | 
 | 	} pte_iterate_hashed_end(); | 
 |  | 
 | #ifdef CONFIG_PPC_TRANSACTIONAL_MEM | 
 | 	/* Transactions are not aborted by tlbiel, only tlbie. | 
 | 	 * Without, syncing a page back to a block device w/ PIO could pick up | 
 | 	 * transactional data (bad!) so we force an abort here.  Before the | 
 | 	 * sync the page will be made read-only, which will flush_hash_page. | 
 | 	 * BIG ISSUE here: if the kernel uses a page from userspace without | 
 | 	 * unmapping it first, it may see the speculated version. | 
 | 	 */ | 
 | 	if (local && cpu_has_feature(CPU_FTR_TM) && | 
 | 	    current->thread.regs && | 
 | 	    MSR_TM_ACTIVE(current->thread.regs->msr)) { | 
 | 		tm_enable(); | 
 | 		tm_abort(TM_CAUSE_TLBI); | 
 | 	} | 
 | #endif | 
 | } | 
 |  | 
 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE | 
 | void flush_hash_hugepage(unsigned long vsid, unsigned long addr, | 
 | 			 pmd_t *pmdp, unsigned int psize, int ssize, | 
 | 			 unsigned long flags) | 
 | { | 
 | 	int i, max_hpte_count, valid; | 
 | 	unsigned long s_addr; | 
 | 	unsigned char *hpte_slot_array; | 
 | 	unsigned long hidx, shift, vpn, hash, slot; | 
 | 	int local = flags & HPTE_LOCAL_UPDATE; | 
 |  | 
 | 	s_addr = addr & HPAGE_PMD_MASK; | 
 | 	hpte_slot_array = get_hpte_slot_array(pmdp); | 
 | 	/* | 
 | 	 * IF we try to do a HUGE PTE update after a withdraw is done. | 
 | 	 * we will find the below NULL. This happens when we do | 
 | 	 * split_huge_page_pmd | 
 | 	 */ | 
 | 	if (!hpte_slot_array) | 
 | 		return; | 
 |  | 
 | 	if (ppc_md.hugepage_invalidate) { | 
 | 		ppc_md.hugepage_invalidate(vsid, s_addr, hpte_slot_array, | 
 | 					   psize, ssize, local); | 
 | 		goto tm_abort; | 
 | 	} | 
 | 	/* | 
 | 	 * No bluk hpte removal support, invalidate each entry | 
 | 	 */ | 
 | 	shift = mmu_psize_defs[psize].shift; | 
 | 	max_hpte_count = HPAGE_PMD_SIZE >> shift; | 
 | 	for (i = 0; i < max_hpte_count; i++) { | 
 | 		/* | 
 | 		 * 8 bits per each hpte entries | 
 | 		 * 000| [ secondary group (one bit) | hidx (3 bits) | valid bit] | 
 | 		 */ | 
 | 		valid = hpte_valid(hpte_slot_array, i); | 
 | 		if (!valid) | 
 | 			continue; | 
 | 		hidx =  hpte_hash_index(hpte_slot_array, i); | 
 |  | 
 | 		/* get the vpn */ | 
 | 		addr = s_addr + (i * (1ul << shift)); | 
 | 		vpn = hpt_vpn(addr, vsid, ssize); | 
 | 		hash = hpt_hash(vpn, shift, ssize); | 
 | 		if (hidx & _PTEIDX_SECONDARY) | 
 | 			hash = ~hash; | 
 |  | 
 | 		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP; | 
 | 		slot += hidx & _PTEIDX_GROUP_IX; | 
 | 		ppc_md.hpte_invalidate(slot, vpn, psize, | 
 | 				       MMU_PAGE_16M, ssize, local); | 
 | 	} | 
 | tm_abort: | 
 | #ifdef CONFIG_PPC_TRANSACTIONAL_MEM | 
 | 	/* Transactions are not aborted by tlbiel, only tlbie. | 
 | 	 * Without, syncing a page back to a block device w/ PIO could pick up | 
 | 	 * transactional data (bad!) so we force an abort here.  Before the | 
 | 	 * sync the page will be made read-only, which will flush_hash_page. | 
 | 	 * BIG ISSUE here: if the kernel uses a page from userspace without | 
 | 	 * unmapping it first, it may see the speculated version. | 
 | 	 */ | 
 | 	if (local && cpu_has_feature(CPU_FTR_TM) && | 
 | 	    current->thread.regs && | 
 | 	    MSR_TM_ACTIVE(current->thread.regs->msr)) { | 
 | 		tm_enable(); | 
 | 		tm_abort(TM_CAUSE_TLBI); | 
 | 	} | 
 | #endif | 
 | 	return; | 
 | } | 
 | #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ | 
 |  | 
 | void flush_hash_range(unsigned long number, int local) | 
 | { | 
 | 	if (ppc_md.flush_hash_range) | 
 | 		ppc_md.flush_hash_range(number, local); | 
 | 	else { | 
 | 		int i; | 
 | 		struct ppc64_tlb_batch *batch = | 
 | 			this_cpu_ptr(&ppc64_tlb_batch); | 
 |  | 
 | 		for (i = 0; i < number; i++) | 
 | 			flush_hash_page(batch->vpn[i], batch->pte[i], | 
 | 					batch->psize, batch->ssize, local); | 
 | 	} | 
 | } | 
 |  | 
 | /* | 
 |  * low_hash_fault is called when we the low level hash code failed | 
 |  * to instert a PTE due to an hypervisor error | 
 |  */ | 
 | void low_hash_fault(struct pt_regs *regs, unsigned long address, int rc) | 
 | { | 
 | 	enum ctx_state prev_state = exception_enter(); | 
 |  | 
 | 	if (user_mode(regs)) { | 
 | #ifdef CONFIG_PPC_SUBPAGE_PROT | 
 | 		if (rc == -2) | 
 | 			_exception(SIGSEGV, regs, SEGV_ACCERR, address); | 
 | 		else | 
 | #endif | 
 | 			_exception(SIGBUS, regs, BUS_ADRERR, address); | 
 | 	} else | 
 | 		bad_page_fault(regs, address, SIGBUS); | 
 |  | 
 | 	exception_exit(prev_state); | 
 | } | 
 |  | 
 | long hpte_insert_repeating(unsigned long hash, unsigned long vpn, | 
 | 			   unsigned long pa, unsigned long rflags, | 
 | 			   unsigned long vflags, int psize, int ssize) | 
 | { | 
 | 	unsigned long hpte_group; | 
 | 	long slot; | 
 |  | 
 | repeat: | 
 | 	hpte_group = ((hash & htab_hash_mask) * | 
 | 		       HPTES_PER_GROUP) & ~0x7UL; | 
 |  | 
 | 	/* Insert into the hash table, primary slot */ | 
 | 	slot = ppc_md.hpte_insert(hpte_group, vpn, pa, rflags, vflags, | 
 | 				  psize, psize, ssize); | 
 |  | 
 | 	/* Primary is full, try the secondary */ | 
 | 	if (unlikely(slot == -1)) { | 
 | 		hpte_group = ((~hash & htab_hash_mask) * | 
 | 			      HPTES_PER_GROUP) & ~0x7UL; | 
 | 		slot = ppc_md.hpte_insert(hpte_group, vpn, pa, rflags, | 
 | 					  vflags | HPTE_V_SECONDARY, | 
 | 					  psize, psize, ssize); | 
 | 		if (slot == -1) { | 
 | 			if (mftb() & 0x1) | 
 | 				hpte_group = ((hash & htab_hash_mask) * | 
 | 					      HPTES_PER_GROUP)&~0x7UL; | 
 |  | 
 | 			ppc_md.hpte_remove(hpte_group); | 
 | 			goto repeat; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	return slot; | 
 | } | 
 |  | 
 | #ifdef CONFIG_DEBUG_PAGEALLOC | 
 | static void kernel_map_linear_page(unsigned long vaddr, unsigned long lmi) | 
 | { | 
 | 	unsigned long hash; | 
 | 	unsigned long vsid = get_kernel_vsid(vaddr, mmu_kernel_ssize); | 
 | 	unsigned long vpn = hpt_vpn(vaddr, vsid, mmu_kernel_ssize); | 
 | 	unsigned long mode = htab_convert_pte_flags(pgprot_val(PAGE_KERNEL)); | 
 | 	long ret; | 
 |  | 
 | 	hash = hpt_hash(vpn, PAGE_SHIFT, mmu_kernel_ssize); | 
 |  | 
 | 	/* Don't create HPTE entries for bad address */ | 
 | 	if (!vsid) | 
 | 		return; | 
 |  | 
 | 	ret = hpte_insert_repeating(hash, vpn, __pa(vaddr), mode, | 
 | 				    HPTE_V_BOLTED, | 
 | 				    mmu_linear_psize, mmu_kernel_ssize); | 
 |  | 
 | 	BUG_ON (ret < 0); | 
 | 	spin_lock(&linear_map_hash_lock); | 
 | 	BUG_ON(linear_map_hash_slots[lmi] & 0x80); | 
 | 	linear_map_hash_slots[lmi] = ret | 0x80; | 
 | 	spin_unlock(&linear_map_hash_lock); | 
 | } | 
 |  | 
 | static void kernel_unmap_linear_page(unsigned long vaddr, unsigned long lmi) | 
 | { | 
 | 	unsigned long hash, hidx, slot; | 
 | 	unsigned long vsid = get_kernel_vsid(vaddr, mmu_kernel_ssize); | 
 | 	unsigned long vpn = hpt_vpn(vaddr, vsid, mmu_kernel_ssize); | 
 |  | 
 | 	hash = hpt_hash(vpn, PAGE_SHIFT, mmu_kernel_ssize); | 
 | 	spin_lock(&linear_map_hash_lock); | 
 | 	BUG_ON(!(linear_map_hash_slots[lmi] & 0x80)); | 
 | 	hidx = linear_map_hash_slots[lmi] & 0x7f; | 
 | 	linear_map_hash_slots[lmi] = 0; | 
 | 	spin_unlock(&linear_map_hash_lock); | 
 | 	if (hidx & _PTEIDX_SECONDARY) | 
 | 		hash = ~hash; | 
 | 	slot = (hash & htab_hash_mask) * HPTES_PER_GROUP; | 
 | 	slot += hidx & _PTEIDX_GROUP_IX; | 
 | 	ppc_md.hpte_invalidate(slot, vpn, mmu_linear_psize, mmu_linear_psize, | 
 | 			       mmu_kernel_ssize, 0); | 
 | } | 
 |  | 
 | void __kernel_map_pages(struct page *page, int numpages, int enable) | 
 | { | 
 | 	unsigned long flags, vaddr, lmi; | 
 | 	int i; | 
 |  | 
 | 	local_irq_save(flags); | 
 | 	for (i = 0; i < numpages; i++, page++) { | 
 | 		vaddr = (unsigned long)page_address(page); | 
 | 		lmi = __pa(vaddr) >> PAGE_SHIFT; | 
 | 		if (lmi >= linear_map_hash_count) | 
 | 			continue; | 
 | 		if (enable) | 
 | 			kernel_map_linear_page(vaddr, lmi); | 
 | 		else | 
 | 			kernel_unmap_linear_page(vaddr, lmi); | 
 | 	} | 
 | 	local_irq_restore(flags); | 
 | } | 
 | #endif /* CONFIG_DEBUG_PAGEALLOC */ | 
 |  | 
 | void hash__setup_initial_memory_limit(phys_addr_t first_memblock_base, | 
 | 				phys_addr_t first_memblock_size) | 
 | { | 
 | 	/* We don't currently support the first MEMBLOCK not mapping 0 | 
 | 	 * physical on those processors | 
 | 	 */ | 
 | 	BUG_ON(first_memblock_base != 0); | 
 |  | 
 | 	/* On LPAR systems, the first entry is our RMA region, | 
 | 	 * non-LPAR 64-bit hash MMU systems don't have a limitation | 
 | 	 * on real mode access, but using the first entry works well | 
 | 	 * enough. We also clamp it to 1G to avoid some funky things | 
 | 	 * such as RTAS bugs etc... | 
 | 	 */ | 
 | 	ppc64_rma_size = min_t(u64, first_memblock_size, 0x40000000); | 
 |  | 
 | 	/* Finally limit subsequent allocations */ | 
 | 	memblock_set_current_limit(ppc64_rma_size); | 
 | } |