diff options
author | Thomas Gleixner <tglx@linutronix.de> | 2007-10-11 11:16:47 +0200 |
---|---|---|
committer | Thomas Gleixner <tglx@linutronix.de> | 2007-10-11 11:16:47 +0200 |
commit | ad757b6aa5801b81dec609d87753604a06313c53 (patch) | |
tree | 7bb40460e1729ad370b5ae75e65f9e6a0e824328 /arch/x86/mm | |
parent | 96ae6ea0be1b902c28b3b463c27da42b41e2b63a (diff) |
i386: move mm
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/mm')
-rw-r--r-- | arch/x86/mm/Makefile | 5 | ||||
-rw-r--r-- | arch/x86/mm/Makefile_32 | 10 | ||||
-rw-r--r-- | arch/x86/mm/boot_ioremap_32.c | 100 | ||||
-rw-r--r-- | arch/x86/mm/discontig_32.c | 431 | ||||
-rw-r--r-- | arch/x86/mm/extable_32.c | 35 | ||||
-rw-r--r-- | arch/x86/mm/fault_32.c | 657 | ||||
-rw-r--r-- | arch/x86/mm/highmem_32.c | 113 | ||||
-rw-r--r-- | arch/x86/mm/hugetlbpage.c | 391 | ||||
-rw-r--r-- | arch/x86/mm/init_32.c | 858 | ||||
-rw-r--r-- | arch/x86/mm/ioremap_32.c | 274 | ||||
-rw-r--r-- | arch/x86/mm/mmap_32.c | 77 | ||||
-rw-r--r-- | arch/x86/mm/pageattr_32.c | 278 | ||||
-rw-r--r-- | arch/x86/mm/pgtable_32.c | 373 |
13 files changed, 3602 insertions, 0 deletions
diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile new file mode 100644 index 00000000000..7317648e658 --- /dev/null +++ b/arch/x86/mm/Makefile @@ -0,0 +1,5 @@ +ifeq ($(CONFIG_X86_32),y) +include ${srctree}/arch/x86/mm/Makefile_32 +else +include ${srctree}/arch/x86_64/mm/Makefile_64 +endif diff --git a/arch/x86/mm/Makefile_32 b/arch/x86/mm/Makefile_32 new file mode 100644 index 00000000000..362b4ad082d --- /dev/null +++ b/arch/x86/mm/Makefile_32 @@ -0,0 +1,10 @@ +# +# Makefile for the linux i386-specific parts of the memory manager. +# + +obj-y := init_32.o pgtable_32.o fault_32.o ioremap_32.o extable_32.o pageattr_32.o mmap_32.o + +obj-$(CONFIG_NUMA) += discontig_32.o +obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o +obj-$(CONFIG_HIGHMEM) += highmem_32.o +obj-$(CONFIG_BOOT_IOREMAP) += boot_ioremap_32.o diff --git a/arch/x86/mm/boot_ioremap_32.c b/arch/x86/mm/boot_ioremap_32.c new file mode 100644 index 00000000000..4de95a17a7d --- /dev/null +++ b/arch/x86/mm/boot_ioremap_32.c @@ -0,0 +1,100 @@ +/* + * arch/i386/mm/boot_ioremap.c + * + * Re-map functions for early boot-time before paging_init() when the + * boot-time pagetables are still in use + * + * Written by Dave Hansen <haveblue@us.ibm.com> + */ + + +/* + * We need to use the 2-level pagetable functions, but CONFIG_X86_PAE + * keeps that from happenning. If anyone has a better way, I'm listening. + * + * boot_pte_t is defined only if this all works correctly + */ + +#undef CONFIG_X86_PAE +#undef CONFIG_PARAVIRT +#include <asm/page.h> +#include <asm/pgtable.h> +#include <asm/tlbflush.h> +#include <linux/init.h> +#include <linux/stddef.h> + +/* + * I'm cheating here. It is known that the two boot PTE pages are + * allocated next to each other. I'm pretending that they're just + * one big array. + */ + +#define BOOT_PTE_PTRS (PTRS_PER_PTE*2) + +static unsigned long boot_pte_index(unsigned long vaddr) +{ + return __pa(vaddr) >> PAGE_SHIFT; +} + +static inline boot_pte_t* boot_vaddr_to_pte(void *address) +{ + boot_pte_t* boot_pg = (boot_pte_t*)pg0; + return &boot_pg[boot_pte_index((unsigned long)address)]; +} + +/* + * This is only for a caller who is clever enough to page-align + * phys_addr and virtual_source, and who also has a preference + * about which virtual address from which to steal ptes + */ +static void __boot_ioremap(unsigned long phys_addr, unsigned long nrpages, + void* virtual_source) +{ + boot_pte_t* pte; + int i; + char *vaddr = virtual_source; + + pte = boot_vaddr_to_pte(virtual_source); + for (i=0; i < nrpages; i++, phys_addr += PAGE_SIZE, pte++) { + set_pte(pte, pfn_pte(phys_addr>>PAGE_SHIFT, PAGE_KERNEL)); + __flush_tlb_one(&vaddr[i*PAGE_SIZE]); + } +} + +/* the virtual space we're going to remap comes from this array */ +#define BOOT_IOREMAP_PAGES 4 +#define BOOT_IOREMAP_SIZE (BOOT_IOREMAP_PAGES*PAGE_SIZE) +static __initdata char boot_ioremap_space[BOOT_IOREMAP_SIZE] + __attribute__ ((aligned (PAGE_SIZE))); + +/* + * This only applies to things which need to ioremap before paging_init() + * bt_ioremap() and plain ioremap() are both useless at this point. + * + * When used, we're still using the boot-time pagetables, which only + * have 2 PTE pages mapping the first 8MB + * + * There is no unmap. The boot-time PTE pages aren't used after boot. + * If you really want the space back, just remap it yourself. + * boot_ioremap(&ioremap_space-PAGE_OFFSET, BOOT_IOREMAP_SIZE) + */ +__init void* boot_ioremap(unsigned long phys_addr, unsigned long size) +{ + unsigned long last_addr, offset; + unsigned int nrpages; + + last_addr = phys_addr + size - 1; + + /* page align the requested address */ + offset = phys_addr & ~PAGE_MASK; + phys_addr &= PAGE_MASK; + size = PAGE_ALIGN(last_addr) - phys_addr; + + nrpages = size >> PAGE_SHIFT; + if (nrpages > BOOT_IOREMAP_PAGES) + return NULL; + + __boot_ioremap(phys_addr, nrpages, boot_ioremap_space); + + return &boot_ioremap_space[offset]; +} diff --git a/arch/x86/mm/discontig_32.c b/arch/x86/mm/discontig_32.c new file mode 100644 index 00000000000..860e912a3fb --- /dev/null +++ b/arch/x86/mm/discontig_32.c @@ -0,0 +1,431 @@ +/* + * Written by: Patricia Gaughen <gone@us.ibm.com>, IBM Corporation + * August 2002: added remote node KVA remap - Martin J. Bligh + * + * Copyright (C) 2002, IBM Corp. + * + * 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; either version 2 of the License, or + * (at your option) any later version. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include <linux/mm.h> +#include <linux/bootmem.h> +#include <linux/mmzone.h> +#include <linux/highmem.h> +#include <linux/initrd.h> +#include <linux/nodemask.h> +#include <linux/module.h> +#include <linux/kexec.h> +#include <linux/pfn.h> +#include <linux/swap.h> + +#include <asm/e820.h> +#include <asm/setup.h> +#include <asm/mmzone.h> +#include <bios_ebda.h> + +struct pglist_data *node_data[MAX_NUMNODES] __read_mostly; +EXPORT_SYMBOL(node_data); +bootmem_data_t node0_bdata; + +/* + * numa interface - we expect the numa architecture specific code to have + * populated the following initialisation. + * + * 1) node_online_map - the map of all nodes configured (online) in the system + * 2) node_start_pfn - the starting page frame number for a node + * 3) node_end_pfn - the ending page fram number for a node + */ +unsigned long node_start_pfn[MAX_NUMNODES] __read_mostly; +unsigned long node_end_pfn[MAX_NUMNODES] __read_mostly; + + +#ifdef CONFIG_DISCONTIGMEM +/* + * 4) physnode_map - the mapping between a pfn and owning node + * physnode_map keeps track of the physical memory layout of a generic + * numa node on a 256Mb break (each element of the array will + * represent 256Mb of memory and will be marked by the node id. so, + * if the first gig is on node 0, and the second gig is on node 1 + * physnode_map will contain: + * + * physnode_map[0-3] = 0; + * physnode_map[4-7] = 1; + * physnode_map[8- ] = -1; + */ +s8 physnode_map[MAX_ELEMENTS] __read_mostly = { [0 ... (MAX_ELEMENTS - 1)] = -1}; +EXPORT_SYMBOL(physnode_map); + +void memory_present(int nid, unsigned long start, unsigned long end) +{ + unsigned long pfn; + + printk(KERN_INFO "Node: %d, start_pfn: %ld, end_pfn: %ld\n", + nid, start, end); + printk(KERN_DEBUG " Setting physnode_map array to node %d for pfns:\n", nid); + printk(KERN_DEBUG " "); + for (pfn = start; pfn < end; pfn += PAGES_PER_ELEMENT) { + physnode_map[pfn / PAGES_PER_ELEMENT] = nid; + printk("%ld ", pfn); + } + printk("\n"); +} + +unsigned long node_memmap_size_bytes(int nid, unsigned long start_pfn, + unsigned long end_pfn) +{ + unsigned long nr_pages = end_pfn - start_pfn; + + if (!nr_pages) + return 0; + + return (nr_pages + 1) * sizeof(struct page); +} +#endif + +extern unsigned long find_max_low_pfn(void); +extern void add_one_highpage_init(struct page *, int, int); +extern unsigned long highend_pfn, highstart_pfn; + +#define LARGE_PAGE_BYTES (PTRS_PER_PTE * PAGE_SIZE) + +unsigned long node_remap_start_pfn[MAX_NUMNODES]; +unsigned long node_remap_size[MAX_NUMNODES]; +unsigned long node_remap_offset[MAX_NUMNODES]; +void *node_remap_start_vaddr[MAX_NUMNODES]; +void set_pmd_pfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags); + +void *node_remap_end_vaddr[MAX_NUMNODES]; +void *node_remap_alloc_vaddr[MAX_NUMNODES]; +static unsigned long kva_start_pfn; +static unsigned long kva_pages; +/* + * FLAT - support for basic PC memory model with discontig enabled, essentially + * a single node with all available processors in it with a flat + * memory map. + */ +int __init get_memcfg_numa_flat(void) +{ + printk("NUMA - single node, flat memory mode\n"); + + /* Run the memory configuration and find the top of memory. */ + find_max_pfn(); + node_start_pfn[0] = 0; + node_end_pfn[0] = max_pfn; + memory_present(0, 0, max_pfn); + + /* Indicate there is one node available. */ + nodes_clear(node_online_map); + node_set_online(0); + return 1; +} + +/* + * Find the highest page frame number we have available for the node + */ +static void __init find_max_pfn_node(int nid) +{ + if (node_end_pfn[nid] > max_pfn) + node_end_pfn[nid] = max_pfn; + /* + * if a user has given mem=XXXX, then we need to make sure + * that the node _starts_ before that, too, not just ends + */ + if (node_start_pfn[nid] > max_pfn) + node_start_pfn[nid] = max_pfn; + BUG_ON(node_start_pfn[nid] > node_end_pfn[nid]); +} + +/* + * Allocate memory for the pg_data_t for this node via a crude pre-bootmem + * method. For node zero take this from the bottom of memory, for + * subsequent nodes place them at node_remap_start_vaddr which contains + * node local data in physically node local memory. See setup_memory() + * for details. + */ +static void __init allocate_pgdat(int nid) +{ + if (nid && node_has_online_mem(nid)) + NODE_DATA(nid) = (pg_data_t *)node_remap_start_vaddr[nid]; + else { + NODE_DATA(nid) = (pg_data_t *)(pfn_to_kaddr(min_low_pfn)); + min_low_pfn += PFN_UP(sizeof(pg_data_t)); + } +} + +void *alloc_remap(int nid, unsigned long size) +{ + void *allocation = node_remap_alloc_vaddr[nid]; + + size = ALIGN(size, L1_CACHE_BYTES); + + if (!allocation || (allocation + size) >= node_remap_end_vaddr[nid]) + return 0; + + node_remap_alloc_vaddr[nid] += size; + memset(allocation, 0, size); + + return allocation; +} + +void __init remap_numa_kva(void) +{ + void *vaddr; + unsigned long pfn; + int node; + + for_each_online_node(node) { + for (pfn=0; pfn < node_remap_size[node]; pfn += PTRS_PER_PTE) { + vaddr = node_remap_start_vaddr[node]+(pfn<<PAGE_SHIFT); + set_pmd_pfn((ulong) vaddr, + node_remap_start_pfn[node] + pfn, + PAGE_KERNEL_LARGE); + } + } +} + +static unsigned long calculate_numa_remap_pages(void) +{ + int nid; + unsigned long size, reserve_pages = 0; + unsigned long pfn; + + for_each_online_node(nid) { + unsigned old_end_pfn = node_end_pfn[nid]; + + /* + * The acpi/srat node info can show hot-add memroy zones + * where memory could be added but not currently present. + */ + if (node_start_pfn[nid] > max_pfn) + continue; + if (node_end_pfn[nid] > max_pfn) + node_end_pfn[nid] = max_pfn; + + /* ensure the remap includes space for the pgdat. */ + size = node_remap_size[nid] + sizeof(pg_data_t); + + /* convert size to large (pmd size) pages, rounding up */ + size = (size + LARGE_PAGE_BYTES - 1) / LARGE_PAGE_BYTES; + /* now the roundup is correct, convert to PAGE_SIZE pages */ + size = size * PTRS_PER_PTE; + + /* + * Validate the region we are allocating only contains valid + * pages. + */ + for (pfn = node_end_pfn[nid] - size; + pfn < node_end_pfn[nid]; pfn++) + if (!page_is_ram(pfn)) + break; + + if (pfn != node_end_pfn[nid]) + size = 0; + + printk("Reserving %ld pages of KVA for lmem_map of node %d\n", + size, nid); + node_remap_size[nid] = size; + node_remap_offset[nid] = reserve_pages; + reserve_pages += size; + printk("Shrinking node %d from %ld pages to %ld pages\n", + nid, node_end_pfn[nid], node_end_pfn[nid] - size); + + if (node_end_pfn[nid] & (PTRS_PER_PTE-1)) { + /* + * Align node_end_pfn[] and node_remap_start_pfn[] to + * pmd boundary. remap_numa_kva will barf otherwise. + */ + printk("Shrinking node %d further by %ld pages for proper alignment\n", + nid, node_end_pfn[nid] & (PTRS_PER_PTE-1)); + size += node_end_pfn[nid] & (PTRS_PER_PTE-1); + } + + node_end_pfn[nid] -= size; + node_remap_start_pfn[nid] = node_end_pfn[nid]; + shrink_active_range(nid, old_end_pfn, node_end_pfn[nid]); + } + printk("Reserving total of %ld pages for numa KVA remap\n", + reserve_pages); + return reserve_pages; +} + +extern void setup_bootmem_allocator(void); +unsigned long __init setup_memory(void) +{ + int nid; + unsigned long system_start_pfn, system_max_low_pfn; + + /* + * When mapping a NUMA machine we allocate the node_mem_map arrays + * from node local memory. They are then mapped directly into KVA + * between zone normal and vmalloc space. Calculate the size of + * this space and use it to adjust the boundry between ZONE_NORMAL + * and ZONE_HIGHMEM. + */ + find_max_pfn(); + get_memcfg_numa(); + + kva_pages = calculate_numa_remap_pages(); + + /* partially used pages are not usable - thus round upwards */ + system_start_pfn = min_low_pfn = PFN_UP(init_pg_tables_end); + + kva_start_pfn = find_max_low_pfn() - kva_pages; + +#ifdef CONFIG_BLK_DEV_INITRD + /* Numa kva area is below the initrd */ + if (LOADER_TYPE && INITRD_START) + kva_start_pfn = PFN_DOWN(INITRD_START) - kva_pages; +#endif + kva_start_pfn -= kva_start_pfn & (PTRS_PER_PTE-1); + + system_max_low_pfn = max_low_pfn = find_max_low_pfn(); + printk("kva_start_pfn ~ %ld find_max_low_pfn() ~ %ld\n", + kva_start_pfn, max_low_pfn); + printk("max_pfn = %ld\n", max_pfn); +#ifdef CONFIG_HIGHMEM + highstart_pfn = highend_pfn = max_pfn; + if (max_pfn > system_max_low_pfn) + highstart_pfn = system_max_low_pfn; + printk(KERN_NOTICE "%ldMB HIGHMEM available.\n", + pages_to_mb(highend_pfn - highstart_pfn)); + num_physpages = highend_pfn; + high_memory = (void *) __va(highstart_pfn * PAGE_SIZE - 1) + 1; +#else + num_physpages = system_max_low_pfn; + high_memory = (void *) __va(system_max_low_pfn * PAGE_SIZE - 1) + 1; +#endif + printk(KERN_NOTICE "%ldMB LOWMEM available.\n", + pages_to_mb(system_max_low_pfn)); + printk("min_low_pfn = %ld, max_low_pfn = %ld, highstart_pfn = %ld\n", + min_low_pfn, max_low_pfn, highstart_pfn); + + printk("Low memory ends at vaddr %08lx\n", + (ulong) pfn_to_kaddr(max_low_pfn)); + for_each_online_node(nid) { + node_remap_start_vaddr[nid] = pfn_to_kaddr( + kva_start_pfn + node_remap_offset[nid]); + /* Init the node remap allocator */ + node_remap_end_vaddr[nid] = node_remap_start_vaddr[nid] + + (node_remap_size[nid] * PAGE_SIZE); + node_remap_alloc_vaddr[nid] = node_remap_start_vaddr[nid] + + ALIGN(sizeof(pg_data_t), PAGE_SIZE); + + allocate_pgdat(nid); + printk ("node %d will remap to vaddr %08lx - %08lx\n", nid, + (ulong) node_remap_start_vaddr[nid], + (ulong) pfn_to_kaddr(highstart_pfn + + node_remap_offset[nid] + node_remap_size[nid])); + } + printk("High memory starts at vaddr %08lx\n", + (ulong) pfn_to_kaddr(highstart_pfn)); + for_each_online_node(nid) + find_max_pfn_node(nid); + + memset(NODE_DATA(0), 0, sizeof(struct pglist_data)); + NODE_DATA(0)->bdata = &node0_bdata; + setup_bootmem_allocator(); + return max_low_pfn; +} + +void __init numa_kva_reserve(void) +{ + reserve_bootmem(PFN_PHYS(kva_start_pfn),PFN_PHYS(kva_pages)); +} + +void __init zone_sizes_init(void) +{ + int nid; + unsigned long max_zone_pfns[MAX_NR_ZONES]; + memset(max_zone_pfns, 0, sizeof(max_zone_pfns)); + max_zone_pfns[ZONE_DMA] = + virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT; + max_zone_pfns[ZONE_NORMAL] = max_low_pfn; +#ifdef CONFIG_HIGHMEM + max_zone_pfns[ZONE_HIGHMEM] = highend_pfn; +#endif + + /* If SRAT has not registered memory, register it now */ + if (find_max_pfn_with_active_regions() == 0) { + for_each_online_node(nid) { + if (node_has_online_mem(nid)) + add_active_range(nid, node_start_pfn[nid], + node_end_pfn[nid]); + } + } + + free_area_init_nodes(max_zone_pfns); + return; +} + +void __init set_highmem_pages_init(int bad_ppro) +{ +#ifdef CONFIG_HIGHMEM + struct zone *zone; + struct page *page; + + for_each_zone(zone) { + unsigned long node_pfn, zone_start_pfn, zone_end_pfn; + + if (!is_highmem(zone)) + continue; + + zone_start_pfn = zone->zone_start_pfn; + zone_end_pfn = zone_start_pfn + zone->spanned_pages; + + printk("Initializing %s for node %d (%08lx:%08lx)\n", + zone->name, zone_to_nid(zone), + zone_start_pfn, zone_end_pfn); + + for (node_pfn = zone_start_pfn; node_pfn < zone_end_pfn; node_pfn++) { + if (!pfn_valid(node_pfn)) + continue; + page = pfn_to_page(node_pfn); + add_one_highpage_init(page, node_pfn, bad_ppro); + } + } + totalram_pages += totalhigh_pages; +#endif +} + +#ifdef CONFIG_MEMORY_HOTPLUG +int paddr_to_nid(u64 addr) +{ + int nid; + unsigned long pfn = PFN_DOWN(addr); + + for_each_node(nid) + if (node_start_pfn[nid] <= pfn && + pfn < node_end_pfn[nid]) + return nid; + + return -1; +} + +/* + * This function is used to ask node id BEFORE memmap and mem_section's + * initialization (pfn_to_nid() can't be used yet). + * If _PXM is not defined on ACPI's DSDT, node id must be found by this. + */ +int memory_add_physaddr_to_nid(u64 addr) +{ + int nid = paddr_to_nid(addr); + return (nid >= 0) ? nid : 0; +} + +EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); +#endif diff --git a/arch/x86/mm/extable_32.c b/arch/x86/mm/extable_32.c new file mode 100644 index 00000000000..0ce4f22a263 --- /dev/null +++ b/arch/x86/mm/extable_32.c @@ -0,0 +1,35 @@ +/* + * linux/arch/i386/mm/extable.c + */ + +#include <linux/module.h> +#include <linux/spinlock.h> +#include <asm/uaccess.h> + +int fixup_exception(struct pt_regs *regs) +{ + const struct exception_table_entry *fixup; + +#ifdef CONFIG_PNPBIOS + if (unlikely(SEGMENT_IS_PNP_CODE(regs->xcs))) + { + extern u32 pnp_bios_fault_eip, pnp_bios_fault_esp; + extern u32 pnp_bios_is_utter_crap; + pnp_bios_is_utter_crap = 1; + printk(KERN_CRIT "PNPBIOS fault.. attempting recovery.\n"); + __asm__ volatile( + "movl %0, %%esp\n\t" + "jmp *%1\n\t" + : : "g" (pnp_bios_fault_esp), "g" (pnp_bios_fault_eip)); + panic("do_trap: can't hit this"); + } +#endif + + fixup = search_exception_tables(regs->eip); + if (fixup) { + regs->eip = fixup->fixup; + return 1; + } + + return 0; +} diff --git a/arch/x86/mm/fault_32.c b/arch/x86/mm/fault_32.c new file mode 100644 index 00000000000..fcb38e7f354 --- /dev/null +++ b/arch/x86/mm/fault_32.c @@ -0,0 +1,657 @@ +/* + * linux/arch/i386/mm/fault.c + * + * Copyright (C) 1995 Linus Torvalds + */ + +#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/smp.h> +#include <linux/interrupt.h> +#include <linux/init.h> +#include <linux/tty.h> +#include <linux/vt_kern.h> /* For unblank_screen() */ +#include <linux/highmem.h> +#include <linux/bootmem.h> /* for max_low_pfn */ +#include <linux/vmalloc.h> +#include <linux/module.h> +#include <linux/kprobes.h> +#include <linux/uaccess.h> +#include <linux/kdebug.h> + +#include <asm/system.h> +#include <asm/desc.h> +#include <asm/segment.h> + +extern void die(const char *,struct pt_regs *,long); + +static ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain); + +int register_page_fault_notifier(struct notifier_block *nb) +{ + vmalloc_sync_all(); + return atomic_notifier_chain_register(¬ify_page_fault_chain, nb); +} +EXPORT_SYMBOL_GPL(register_page_fault_notifier); + +int unregister_page_fault_notifier(struct notifier_block *nb) +{ + return atomic_notifier_chain_unregister(¬ify_page_fault_chain, nb); +} +EXPORT_SYMBOL_GPL(unregister_page_fault_notifier); + +static inline int notify_page_fault(struct pt_regs *regs, long err) +{ + struct die_args args = { + .regs = regs, + .str = "page fault", + .err = err, + .trapnr = 14, + .signr = SIGSEGV + }; + return atomic_notifier_call_chain(¬ify_page_fault_chain, + DIE_PAGE_FAULT, &args); +} + +/* + * Return EIP plus the CS segment base. The segment limit is also + * adjusted, clamped to the kernel/user address space (whichever is + * appropriate), and returned in *eip_limit. + * + * The segment is checked, because it might have been changed by another + * task between the original faulting instruction and here. + * + * If CS is no longer a valid code segment, or if EIP is beyond the + * limit, or if it is a kernel address when CS is not a kernel segment, + * then the returned value will be greater than *eip_limit. + * + * This is slow, but is very rarely executed. + */ +static inline unsigned long get_segment_eip(struct pt_regs *regs, + unsigned long *eip_limit) +{ + unsigned long eip = regs->eip; + unsigned seg = regs->xcs & 0xffff; + u32 seg_ar, seg_limit, base, *desc; + + /* Unlikely, but must come before segment checks. */ + if (unlikely(regs->eflags & VM_MASK)) { + base = seg << 4; + *eip_limit = base + 0xffff; + return base + (eip & 0xffff); + } + + /* The standard kernel/user address space limit. */ + *eip_limit = user_mode(regs) ? USER_DS.seg : KERNEL_DS.seg; + + /* By far the most common cases. */ + if (likely(SEGMENT_IS_FLAT_CODE(seg))) + return eip; + + /* Check the segment exists, is within the current LDT/GDT size, + that kernel/user (ring 0..3) has the appropriate privilege, + that it's a code segment, and get the limit. */ + __asm__ ("larl %3,%0; lsll %3,%1" + : "=&r" (seg_ar), "=r" (seg_limit) : "0" (0), "rm" (seg)); + if ((~seg_ar & 0x9800) || eip > seg_limit) { + *eip_limit = 0; + return 1; /* So that returned eip > *eip_limit. */ + } + + /* Get the GDT/LDT descriptor base. + When you look for races in this code remember that + LDT and other horrors are only used in user space. */ + if (seg & (1<<2)) { + /* Must lock the LDT while reading it. */ + down(¤t->mm->context.sem); + desc = current->mm->context.ldt; + desc = (void *)desc + (seg & ~7); + } else { + /* Must disable preemption while reading the GDT. */ + desc = (u32 *)get_cpu_gdt_table(get_cpu()); + desc = (void *)desc + (seg & ~7); + } + + /* Decode the code segment base from the descriptor */ + base = get_desc_base((unsigned long *)desc); + + if (seg & (1<<2)) { + up(¤t->mm->context.sem); + } else + put_cpu(); + + /* Adjust EIP and segment limit, and clamp at the kernel limit. + It's legitimate for segments to wrap at 0xffffffff. */ + seg_limit += base; + if (seg_limit < *eip_limit && seg_limit >= base) + *eip_limit = seg_limit; + return eip + base; +} + +/* + * Sometimes AMD Athlon/Opteron CPUs report invalid exceptions on prefetch. + * Check that here and ignore it. + */ +static int __is_prefetch(struct pt_regs *regs, unsigned long addr) +{ + unsigned long limit; + unsigned char *instr = (unsigned char *)get_segment_eip (regs, &limit); + int scan_more = 1; + int prefetch = 0; + int i; + + for (i = 0; scan_more && i < 15; i++) { + unsigned char opcode; + unsigned char instr_hi; + unsigned char instr_lo; + + if (instr > (unsigned char *)limit) + break; + if (probe_kernel_address(instr, opcode)) + break; + + instr_hi = opcode & 0xf0; + instr_lo = opcode & 0x0f; + instr++; + + switch (instr_hi) { + case 0x20: + case 0x30: + /* Values 0x26,0x2E,0x36,0x3E are valid x86 prefixes. */ + scan_more = ((instr_lo & 7) == 0x6); + break; + + case 0x60: + /* 0x64 thru 0x67 are valid prefixes in all modes. */ + scan_more = (instr_lo & 0xC) == 0x4; + break; + case 0xF0: + /* 0xF0, 0xF2, and 0xF3 are valid prefixes */ + scan_more = !instr_lo || (instr_lo>>1) == 1; + break; + case 0x00: + /* Prefetch instruction is 0x0F0D or 0x0F18 */ + scan_more = 0; + if (instr > (unsigned char *)limit) + break; + if (probe_kernel_address(instr, opcode)) + break; + prefetch = (instr_lo == 0xF) && + (opcode == 0x0D || opcode == 0x18); + break; + default: + scan_more = 0; + break; + } + } + return prefetch; +} + +static inline int is_prefetch(struct pt_regs *regs, unsigned long addr, + unsigned long error_code) +{ + if (unlikely(boot_cpu_data.x86_vendor == X86_VENDOR_AMD && + boot_cpu_data.x86 >= 6)) { + /* Catch an obscure case of prefetch inside an NX page. */ + if (nx_enabled && (error_code & 16)) + return 0; + return __is_prefetch(regs, addr); + } + return 0; +} + +static noinline void force_sig_info_fault(int si_signo, int si_code, + unsigned long address, struct task_struct *tsk) +{ + siginfo_t info; + + info.si_signo = si_signo; + info.si_errno = 0; + info.si_code = si_code; + info.si_addr = (void __user *)address; + force_sig_info(si_signo, &info, tsk); +} + +fastcall void do_invalid_op(struct pt_regs *, unsigned long); + +static inline pmd_t *vmalloc_sync_one(pgd_t *pgd, unsigned long address) +{ + unsigned index = pgd_index(address); + pgd_t *pgd_k; + pud_t *pud, *pud_k; + pmd_t *pmd, *pmd_k; + + pgd += index; + pgd_k = init_mm.pgd + index; + + if (!pgd_present(*pgd_k)) + return NULL; + + /* + * set_pgd(pgd, *pgd_k); here would be useless on PAE + * and redundant with the set_pmd() on non-PAE. As would + * set_pud. + */ + + pud = pud_offset(pgd, address); + pud_k = pud_offset(pgd_k, address); + if (!pud_present(*pud_k)) + return NULL; + + pmd = pmd_offset(pud, address); + pmd_k = pmd_offset(pud_k, address); + if (!pmd_present(*pmd_k)) + return NULL; + if (!pmd_present(*pmd)) { + set_pmd(pmd, *pmd_k); + arch_flush_lazy_mmu_mode(); + } else + BUG_ON(pmd_page(*pmd) != pmd_page(*pmd_k)); + return pmd_k; +} + +/* + * Handle a fault on the vmalloc or module mapping area + * + * This assumes no large pages in there. + */ +static inline int vmalloc_fault(unsigned long address) +{ + unsigned long pgd_paddr; + pmd_t *pmd_k; + pte_t *pte_k; + /* + * Synchronize this task's top level page-table + * with the 'reference' page table. + * + * Do _not_ use "current" here. We might be inside + * an interrupt in the middle of a task switch.. + */ + pgd_paddr = read_cr3(); + pmd_k = vmalloc_sync_one(__va(pgd_paddr), address); + if (!pmd_k) + return -1; + pte_k = pte_offset_kernel(pmd_k, address); + if (!pte_present(*pte_k)) + return -1; + return 0; +} + +int show_unhandled_signals = 1; + +/* + * This routine handles page faults. It determines the address, + * and the problem, and then passes it off to one of the appropriate + * routines. + * + * error_code: + * bit 0 == 0 means no page found, 1 means protection fault + * bit 1 == 0 means read, 1 means write + * bit 2 == 0 means kernel, 1 means user-mode + * bit 3 == 1 means use of reserved bit detected + * bit 4 == 1 means fault was an instruction fetch + */ +fastcall void __kprobes do_page_fault(struct pt_regs *regs, + unsigned long error_code) +{ + struct task_struct *tsk; + struct mm_struct *mm; + struct vm_area_struct * vma; + unsigned long address; + int write, si_code; + int fault; + + /* get the address */ + address = read_cr2(); + + tsk = current; + + si_code = SEGV_MAPERR; + + /* + * We fault-in kernel-space virtual memory on-demand. The + * 'reference' page table is init_mm.pgd. + * + * NOTE! We MUST NOT take any locks for this case. We may + * be in an interrupt or a critical region, and should + * only copy the information from the master page table, + * nothing more. + * + * This verifies that the fault happens in kernel space + * (error_code & 4) == 0, and that the fault was not a + * protection error (error_code & 9) == 0. + */ + if (unlikely(address >= TASK_SIZE)) { + if (!(error_code & 0x0000000d) && vmalloc_fault(address) >= 0) + return; + if (notify_page_fault(regs, error_code) == NOTIFY_STOP) + return; + /* + * Don't take the mm semaphore here. If we fixup a prefetch + * fault we could otherwise deadlock. + */ + goto bad_area_nosemaphore; + } + + if (notify_page_fault(regs, error_code) == NOTIFY_STOP) + return; + + /* It's safe to allow irq's after cr2 has been saved and the vmalloc + fault has been handled. */ + if (regs->eflags & (X86_EFLAGS_IF|VM_MASK)) + local_irq_enable(); + + mm = tsk->mm; + + /* + * If we're in an interrupt, have no user context or are running in an + * atomic region then we must not take the fault.. + */ + if (in_atomic() || !mm) + goto bad_area_nosemaphore; + + /* When running in the kernel we expect faults to occur only to + * addresses in user space. All other faults represent errors in the + * kernel and should generate an OOPS. Unfortunatly, in the case of an + * erroneous fault occurring in a code path which already holds mmap_sem + * we will deadlock attempting to validate the fault against the + * address space. Luckily the kernel only validly references user + * space from well defined areas of code, which are listed in the + * exceptions table. + * + * As the vast majority of faults will be valid we will only perform + * the source reference check when there is a possibilty of a deadlock. + * Attempt to lock the address space, if we cannot we then validate the + * source. If this is invalid we can skip the address space check, + * thus avoiding the deadlock. + */ + if (!down_read_trylock(&mm->mmap_sem)) { + if ((error_code & 4) == 0 && + !search_exception_tables(regs->eip)) + goto bad_area_nosemaphore; + down_read(&mm->mmap_sem); + } + + vma = find_vma(mm, address); + if (!vma) + goto bad_area; + if (vma->vm_start <= address) + goto good_area; + if (!(vma->vm_flags & VM_GROWSDOWN)) + goto bad_area; + if (error_code & 4) { + /* + * Accessing the stack below %esp is always a bug. + * The large cushion allows instructions like enter + * and pusha to work. ("enter $65535,$31" pushes + * 32 pointers and then decrements %esp by 65535.) + */ + if (address + 65536 + 32 * sizeof(unsigned long) < regs->esp) + goto bad_area; + } + if (expand_stack(vma, address)) + goto bad_area; +/* + * Ok, we have a good vm_area for this memory access, so + * we can handle it.. + */ +good_area: + si_code = SEGV_ACCERR; + write = 0; + switch (error_code & 3) { + default: /* 3: write, present */ + /* fall through */ + case 2: /* write, not present */ + if (!(vma->vm_flags & VM_WRITE)) + goto bad_ |