linux/arch/x86/kernel/tboot.c
Luis R. Rodriguez 44ecf0ef90 x86/tboot: Remove paravirt_enabled() use
There is already a check for boot_params.tboot_addr prior
to paravirt_enabled(). Both Xen and lguest, which are also the
only ones that set paravirt_enabled to true, never set the
boot_params.tboot_addr. The Xen folks are sure a force disable
to 0 is not needed, we recently forced disabled this on lguest.
With this in place this check is no longer needed.

Xen folks are sure force disable to 0 is not needed because
apm_info lives in .bss, we recently forced disabled this on
lguest, and on the Xen side just to be sure Boris zeroed out
the .bss for PV guests through commit 04b6b4a568
("xen/x86: Zero out .bss for PV guests"). With this care taken
into consideration the paravirt_enabled() check is simply not
needed anymore.

Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: andrew.cooper3@citrix.com
Cc: andriy.shevchenko@linux.intel.com
Cc: bigeasy@linutronix.de
Cc: boris.ostrovsky@oracle.com
Cc: david.vrabel@citrix.com
Cc: ffainelli@freebox.fr
Cc: george.dunlap@citrix.com
Cc: glin@suse.com
Cc: jgross@suse.com
Cc: jlee@suse.com
Cc: josh@joshtriplett.org
Cc: julien.grall@linaro.org
Cc: konrad.wilk@oracle.com
Cc: kozerkov@parallels.com
Cc: lenb@kernel.org
Cc: lguest@lists.ozlabs.org
Cc: linux-acpi@vger.kernel.org
Cc: lv.zheng@intel.com
Cc: matt@codeblueprint.co.uk
Cc: mbizon@freebox.fr
Cc: rjw@rjwysocki.net
Cc: robert.moore@intel.com
Cc: rusty@rustcorp.com.au
Cc: tiwai@suse.de
Cc: toshi.kani@hp.com
Cc: xen-devel@lists.xensource.com
Link: http://lkml.kernel.org/r/1460592286-300-10-git-send-email-mcgrof@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-22 10:29:04 +02:00

533 lines
13 KiB
C

/*
* 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/export.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 <linux/debugfs.h>
#include <asm/realmode.h>
#include <asm/processor.h>
#include <asm/bootparam.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/swiotlb.h>
#include <asm/fixmap.h>
#include <asm/proto.h>
#include <asm/setup.h>
#include <asm/e820.h>
#include <asm/io.h>
#include "../realmode/rm/wakeup.h"
/* Global pointer to shared data; NULL means no measured launch. */
struct tboot *tboot __read_mostly;
EXPORT_SYMBOL(tboot);
/* 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;
}
/* 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),
};
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 (tboot->num_mac_regions >= MAX_TB_MAC_REGIONS)
panic("tboot: Too many MAC regions\n");
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)
{
int i;
tboot->num_mac_regions = 0;
for (i = 0; i < e820.nr_map; i++) {
if ((e820.map[i].type != E820_RAM)
&& (e820.map[i].type != E820_RESERVED_KERN))
continue;
add_mac_region(e820.map[i].addr, e820.map[i].size);
}
tboot->acpi_sinfo.kernel_s3_resume_vector =
real_mode_header->wakeup_start;
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);
}
static int 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 0;
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 -1;
}
tboot_shutdown(acpi_shutdown_map[sleep_state]);
return 0;
}
static int tboot_extended_sleep(u8 sleep_state, u32 val_a, u32 val_b)
{
if (!tboot_enabled())
return 0;
pr_warning("tboot is not able to suspend on platforms with reduced hardware sleep (ACPIv5)");
return -ENODEV;
}
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 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 =
{
.notifier_call = tboot_cpu_callback,
};
#ifdef CONFIG_DEBUG_FS
#define TBOOT_LOG_UUID { 0x26, 0x25, 0x19, 0xc0, 0x30, 0x6b, 0xb4, 0x4d, \
0x4c, 0x84, 0xa3, 0xe9, 0x53, 0xb8, 0x81, 0x74 }
#define TBOOT_SERIAL_LOG_ADDR 0x60000
#define TBOOT_SERIAL_LOG_SIZE 0x08000
#define LOG_MAX_SIZE_OFF 16
#define LOG_BUF_OFF 24
static uint8_t tboot_log_uuid[16] = TBOOT_LOG_UUID;
static ssize_t tboot_log_read(struct file *file, char __user *user_buf, size_t count, loff_t *ppos)
{
void __iomem *log_base;
u8 log_uuid[16];
u32 max_size;
void *kbuf;
int ret = -EFAULT;
log_base = ioremap_nocache(TBOOT_SERIAL_LOG_ADDR, TBOOT_SERIAL_LOG_SIZE);
if (!log_base)
return ret;
memcpy_fromio(log_uuid, log_base, sizeof(log_uuid));
if (memcmp(&tboot_log_uuid, log_uuid, sizeof(log_uuid)))
goto err_iounmap;
max_size = readl(log_base + LOG_MAX_SIZE_OFF);
if (*ppos >= max_size) {
ret = 0;
goto err_iounmap;
}
if (*ppos + count > max_size)
count = max_size - *ppos;
kbuf = kmalloc(count, GFP_KERNEL);
if (!kbuf) {
ret = -ENOMEM;
goto err_iounmap;
}
memcpy_fromio(kbuf, log_base + LOG_BUF_OFF + *ppos, count);
if (copy_to_user(user_buf, kbuf, count))
goto err_kfree;
*ppos += count;
ret = count;
err_kfree:
kfree(kbuf);
err_iounmap:
iounmap(log_base);
return ret;
}
static const struct file_operations tboot_log_fops = {
.read = tboot_log_read,
.llseek = default_llseek,
};
#endif /* CONFIG_DEBUG_FS */
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);
#ifdef CONFIG_DEBUG_FS
debugfs_create_file("tboot_log", S_IRUSR,
arch_debugfs_dir, NULL, &tboot_log_fops);
#endif
acpi_os_set_prepare_sleep(&tboot_sleep);
acpi_os_set_prepare_extended_sleep(&tboot_extended_sleep);
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;
}