diff options
Diffstat (limited to 'arch/x86/kernel/tboot.c')
| -rw-r--r-- | arch/x86/kernel/tboot.c | 447 |
1 files changed, 447 insertions, 0 deletions
diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c new file mode 100644 index 00000000000..86c9f91b48a --- /dev/null +++ b/arch/x86/kernel/tboot.c @@ -0,0 +1,447 @@ +/* + * tboot.c: main implementation of helper functions used by kernel for + * runtime support of Intel(R) Trusted Execution Technology + * + * Copyright (c) 2006-2009, Intel Corporation + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. 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., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * + */ + +#include <linux/dma_remapping.h> +#include <linux/init_task.h> +#include <linux/spinlock.h> +#include <linux/delay.h> +#include <linux/sched.h> +#include <linux/init.h> +#include <linux/dmar.h> +#include <linux/cpu.h> +#include <linux/pfn.h> +#include <linux/mm.h> +#include <linux/tboot.h> + +#include <asm/trampoline.h> +#include <asm/processor.h> +#include <asm/bootparam.h> +#include <asm/pgtable.h> +#include <asm/pgalloc.h> +#include <asm/fixmap.h> +#include <asm/proto.h> +#include <asm/setup.h> +#include <asm/e820.h> +#include <asm/io.h> + +#include "acpi/realmode/wakeup.h" + +/* Global pointer to shared data; NULL means no measured launch. */ +struct tboot *tboot __read_mostly; + +/* timeout for APs (in secs) to enter wait-for-SIPI state during shutdown */ +#define AP_WAIT_TIMEOUT 1 + +#undef pr_fmt +#define pr_fmt(fmt) "tboot: " fmt + +static u8 tboot_uuid[16] __initdata = TBOOT_UUID; + +void __init tboot_probe(void) +{ + /* Look for valid page-aligned address for shared page. */ + if (!boot_params.tboot_addr) + return; + /* + * also verify that it is mapped as we expect it before calling + * set_fixmap(), to reduce chance of garbage value causing crash + */ + if (!e820_any_mapped(boot_params.tboot_addr, + boot_params.tboot_addr, E820_RESERVED)) { + pr_warning("non-0 tboot_addr but it is not of type E820_RESERVED\n"); + return; + } + + /* only a natively booted kernel should be using TXT */ + if (paravirt_enabled()) { + pr_warning("non-0 tboot_addr but pv_ops is enabled\n"); + return; + } + + /* Map and check for tboot UUID. */ + set_fixmap(FIX_TBOOT_BASE, boot_params.tboot_addr); + tboot = (struct tboot *)fix_to_virt(FIX_TBOOT_BASE); + if (memcmp(&tboot_uuid, &tboot->uuid, sizeof(tboot->uuid))) { + pr_warning("tboot at 0x%llx is invalid\n", + boot_params.tboot_addr); + tboot = NULL; + return; + } + if (tboot->version < 5) { + pr_warning("tboot version is invalid: %u\n", tboot->version); + tboot = NULL; + return; + } + + pr_info("found shared page at phys addr 0x%llx:\n", + boot_params.tboot_addr); + pr_debug("version: %d\n", tboot->version); + pr_debug("log_addr: 0x%08x\n", tboot->log_addr); + pr_debug("shutdown_entry: 0x%x\n", tboot->shutdown_entry); + pr_debug("tboot_base: 0x%08x\n", tboot->tboot_base); + pr_debug("tboot_size: 0x%x\n", tboot->tboot_size); +} + +static pgd_t *tboot_pg_dir; +static struct mm_struct tboot_mm = { + .mm_rb = RB_ROOT, + .pgd = swapper_pg_dir, + .mm_users = ATOMIC_INIT(2), + .mm_count = ATOMIC_INIT(1), + .mmap_sem = __RWSEM_INITIALIZER(init_mm.mmap_sem), + .page_table_lock = __SPIN_LOCK_UNLOCKED(init_mm.page_table_lock), + .mmlist = LIST_HEAD_INIT(init_mm.mmlist), + .cpu_vm_mask = CPU_MASK_ALL, +}; + +static inline void switch_to_tboot_pt(void) +{ + write_cr3(virt_to_phys(tboot_pg_dir)); +} + +static int map_tboot_page(unsigned long vaddr, unsigned long pfn, + pgprot_t prot) +{ + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + pte_t *pte; + + pgd = pgd_offset(&tboot_mm, vaddr); + pud = pud_alloc(&tboot_mm, pgd, vaddr); + if (!pud) + return -1; + pmd = pmd_alloc(&tboot_mm, pud, vaddr); + if (!pmd) + return -1; + pte = pte_alloc_map(&tboot_mm, pmd, vaddr); + if (!pte) + return -1; + set_pte_at(&tboot_mm, vaddr, pte, pfn_pte(pfn, prot)); + pte_unmap(pte); + return 0; +} + +static int map_tboot_pages(unsigned long vaddr, unsigned long start_pfn, + unsigned long nr) +{ + /* Reuse the original kernel mapping */ + tboot_pg_dir = pgd_alloc(&tboot_mm); + if (!tboot_pg_dir) + return -1; + + for (; nr > 0; nr--, vaddr += PAGE_SIZE, start_pfn++) { + if (map_tboot_page(vaddr, start_pfn, PAGE_KERNEL_EXEC)) + return -1; + } + + return 0; +} + +static void tboot_create_trampoline(void) +{ + u32 map_base, map_size; + + /* Create identity map for tboot shutdown code. */ + map_base = PFN_DOWN(tboot->tboot_base); + map_size = PFN_UP(tboot->tboot_size); + if (map_tboot_pages(map_base << PAGE_SHIFT, map_base, map_size)) + panic("tboot: Error mapping tboot pages (mfns) @ 0x%x, 0x%x\n", + map_base, map_size); +} + +#ifdef CONFIG_ACPI_SLEEP + +static void add_mac_region(phys_addr_t start, unsigned long size) +{ + struct tboot_mac_region *mr; + phys_addr_t end = start + size; + + if (start && size) { + mr = &tboot->mac_regions[tboot->num_mac_regions++]; + mr->start = round_down(start, PAGE_SIZE); + mr->size = round_up(end, PAGE_SIZE) - mr->start; + } +} + +static int tboot_setup_sleep(void) +{ + tboot->num_mac_regions = 0; + + /* S3 resume code */ + add_mac_region(acpi_wakeup_address, WAKEUP_SIZE); + +#ifdef CONFIG_X86_TRAMPOLINE + /* AP trampoline code */ + add_mac_region(virt_to_phys(trampoline_base), TRAMPOLINE_SIZE); +#endif + + /* kernel code + data + bss */ + add_mac_region(virt_to_phys(_text), _end - _text); + + tboot->acpi_sinfo.kernel_s3_resume_vector = acpi_wakeup_address; + + return 0; +} + +#else /* no CONFIG_ACPI_SLEEP */ + +static int tboot_setup_sleep(void) +{ + /* S3 shutdown requested, but S3 not supported by the kernel... */ + BUG(); + return -1; +} + +#endif + +void tboot_shutdown(u32 shutdown_type) +{ + void (*shutdown)(void); + + if (!tboot_enabled()) + return; + + /* + * if we're being called before the 1:1 mapping is set up then just + * return and let the normal shutdown happen; this should only be + * due to very early panic() + */ + if (!tboot_pg_dir) + return; + + /* if this is S3 then set regions to MAC */ + if (shutdown_type == TB_SHUTDOWN_S3) + if (tboot_setup_sleep()) + return; + + tboot->shutdown_type = shutdown_type; + + switch_to_tboot_pt(); + + shutdown = (void(*)(void))(unsigned long)tboot->shutdown_entry; + shutdown(); + + /* should not reach here */ + while (1) + halt(); +} + +static void tboot_copy_fadt(const struct acpi_table_fadt *fadt) +{ +#define TB_COPY_GAS(tbg, g) \ + tbg.space_id = g.space_id; \ + tbg.bit_width = g.bit_width; \ + tbg.bit_offset = g.bit_offset; \ + tbg.access_width = g.access_width; \ + tbg.address = g.address; + + TB_COPY_GAS(tboot->acpi_sinfo.pm1a_cnt_blk, fadt->xpm1a_control_block); + TB_COPY_GAS(tboot->acpi_sinfo.pm1b_cnt_blk, fadt->xpm1b_control_block); + TB_COPY_GAS(tboot->acpi_sinfo.pm1a_evt_blk, fadt->xpm1a_event_block); + TB_COPY_GAS(tboot->acpi_sinfo.pm1b_evt_blk, fadt->xpm1b_event_block); + + /* + * We need phys addr of waking vector, but can't use virt_to_phys() on + * &acpi_gbl_FACS because it is ioremap'ed, so calc from FACS phys + * addr. + */ + tboot->acpi_sinfo.wakeup_vector = fadt->facs + + offsetof(struct acpi_table_facs, firmware_waking_vector); +} + +void tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control) +{ + static u32 acpi_shutdown_map[ACPI_S_STATE_COUNT] = { + /* S0,1,2: */ -1, -1, -1, + /* S3: */ TB_SHUTDOWN_S3, + /* S4: */ TB_SHUTDOWN_S4, + /* S5: */ TB_SHUTDOWN_S5 }; + + if (!tboot_enabled()) + return; + + tboot_copy_fadt(&acpi_gbl_FADT); + tboot->acpi_sinfo.pm1a_cnt_val = pm1a_control; + tboot->acpi_sinfo.pm1b_cnt_val = pm1b_control; + /* we always use the 32b wakeup vector */ + tboot->acpi_sinfo.vector_width = 32; + + if (sleep_state >= ACPI_S_STATE_COUNT || + acpi_shutdown_map[sleep_state] == -1) { + pr_warning("unsupported sleep state 0x%x\n", sleep_state); + return; + } + + tboot_shutdown(acpi_shutdown_map[sleep_state]); +} + +static atomic_t ap_wfs_count; + +static int tboot_wait_for_aps(int num_aps) +{ + unsigned long timeout; + + timeout = AP_WAIT_TIMEOUT*HZ; + while (atomic_read((atomic_t *)&tboot->num_in_wfs) != num_aps && + timeout) { + mdelay(1); + timeout--; + } + + if (timeout) + pr_warning("tboot wait for APs timeout\n"); + + return !(atomic_read((atomic_t *)&tboot->num_in_wfs) == num_aps); +} + +static int __cpuinit tboot_cpu_callback(struct notifier_block *nfb, + unsigned long action, void *hcpu) +{ + switch (action) { + case CPU_DYING: + atomic_inc(&ap_wfs_count); + if (num_online_cpus() == 1) + if (tboot_wait_for_aps(atomic_read(&ap_wfs_count))) + return NOTIFY_BAD; + break; + } + return NOTIFY_OK; +} + +static struct notifier_block tboot_cpu_notifier __cpuinitdata = +{ + .notifier_call = tboot_cpu_callback, +}; + +static __init int tboot_late_init(void) +{ + if (!tboot_enabled()) + return 0; + + tboot_create_trampoline(); + + atomic_set(&ap_wfs_count, 0); + register_hotcpu_notifier(&tboot_cpu_notifier); + return 0; +} + +late_initcall(tboot_late_init); + +/* + * TXT configuration registers (offsets from TXT_{PUB, PRIV}_CONFIG_REGS_BASE) + */ + +#define TXT_PUB_CONFIG_REGS_BASE 0xfed30000 +#define TXT_PRIV_CONFIG_REGS_BASE 0xfed20000 + +/* # pages for each config regs space - used by fixmap */ +#define NR_TXT_CONFIG_PAGES ((TXT_PUB_CONFIG_REGS_BASE - \ + TXT_PRIV_CONFIG_REGS_BASE) >> PAGE_SHIFT) + +/* offsets from pub/priv config space */ +#define TXTCR_HEAP_BASE 0x0300 +#define TXTCR_HEAP_SIZE 0x0308 + +#define SHA1_SIZE 20 + +struct sha1_hash { + u8 hash[SHA1_SIZE]; +}; + +struct sinit_mle_data { + u32 version; /* currently 6 */ + struct sha1_hash bios_acm_id; + u32 edx_senter_flags; + u64 mseg_valid; + struct sha1_hash sinit_hash; + struct sha1_hash mle_hash; + struct sha1_hash stm_hash; + struct sha1_hash lcp_policy_hash; + u32 lcp_policy_control; + u32 rlp_wakeup_addr; + u32 reserved; + u32 num_mdrs; + u32 mdrs_off; + u32 num_vtd_dmars; + u32 vtd_dmars_off; +} __packed; + +struct acpi_table_header *tboot_get_dmar_table(struct acpi_table_header *dmar_tbl) +{ + void *heap_base, *heap_ptr, *config; + + if (!tboot_enabled()) + return dmar_tbl; + + /* + * ACPI tables may not be DMA protected by tboot, so use DMAR copy + * SINIT saved in SinitMleData in TXT heap (which is DMA protected) + */ + + /* map config space in order to get heap addr */ + config = ioremap(TXT_PUB_CONFIG_REGS_BASE, NR_TXT_CONFIG_PAGES * + PAGE_SIZE); + if (!config) + return NULL; + + /* now map TXT heap */ + heap_base = ioremap(*(u64 *)(config + TXTCR_HEAP_BASE), + *(u64 *)(config + TXTCR_HEAP_SIZE)); + iounmap(config); + if (!heap_base) + return NULL; + + /* walk heap to SinitMleData */ + /* skip BiosData */ + heap_ptr = heap_base + *(u64 *)heap_base; + /* skip OsMleData */ + heap_ptr += *(u64 *)heap_ptr; + /* skip OsSinitData */ + heap_ptr += *(u64 *)heap_ptr; + /* now points to SinitMleDataSize; set to SinitMleData */ + heap_ptr += sizeof(u64); + /* get addr of DMAR table */ + dmar_tbl = (struct acpi_table_header *)(heap_ptr + + ((struct sinit_mle_data *)heap_ptr)->vtd_dmars_off - + sizeof(u64)); + + /* don't unmap heap because dmar.c needs access to this */ + + return dmar_tbl; +} + +int tboot_force_iommu(void) +{ + if (!tboot_enabled()) + return 0; + + if (no_iommu || swiotlb || dmar_disabled) + pr_warning("Forcing Intel-IOMMU to enabled\n"); + + dmar_disabled = 0; +#ifdef CONFIG_SWIOTLB + swiotlb = 0; +#endif + no_iommu = 0; + + return 1; +} |