x86, intel_txt: tboot.c needs <asm/fixmap.h>
[linux-2.6.git] / arch / x86 / kernel / tboot.c
1 /*
2  * tboot.c: main implementation of helper functions used by kernel for
3  *          runtime support of Intel(R) Trusted Execution Technology
4  *
5  * Copyright (c) 2006-2009, Intel Corporation
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms and conditions of the GNU General Public License,
9  * version 2, as published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
14  * more details.
15  *
16  * You should have received a copy of the GNU General Public License along with
17  * this program; if not, write to the Free Software Foundation, Inc.,
18  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
19  *
20  */
21
22 #include <linux/dma_remapping.h>
23 #include <linux/init_task.h>
24 #include <linux/spinlock.h>
25 #include <linux/sched.h>
26 #include <linux/init.h>
27 #include <linux/dmar.h>
28 #include <linux/pfn.h>
29 #include <linux/mm.h>
30
31 #include <asm/trampoline.h>
32 #include <asm/processor.h>
33 #include <asm/bootparam.h>
34 #include <asm/pgtable.h>
35 #include <asm/pgalloc.h>
36 #include <asm/fixmap.h>
37 #include <asm/setup.h>
38 #include <asm/tboot.h>
39 #include <asm/e820.h>
40 #include <asm/io.h>
41
42 #include "acpi/realmode/wakeup.h"
43
44 /* Global pointer to shared data; NULL means no measured launch. */
45 struct tboot *tboot __read_mostly;
46
47 /* timeout for APs (in secs) to enter wait-for-SIPI state during shutdown */
48 #define AP_WAIT_TIMEOUT         1
49
50 #undef pr_fmt
51 #define pr_fmt(fmt)     "tboot: " fmt
52
53 static u8 tboot_uuid[16] __initdata = TBOOT_UUID;
54
55 void __init tboot_probe(void)
56 {
57         /* Look for valid page-aligned address for shared page. */
58         if (!boot_params.tboot_addr)
59                 return;
60         /*
61          * also verify that it is mapped as we expect it before calling
62          * set_fixmap(), to reduce chance of garbage value causing crash
63          */
64         if (!e820_any_mapped(boot_params.tboot_addr,
65                              boot_params.tboot_addr, E820_RESERVED)) {
66                 pr_warning("non-0 tboot_addr but it is not of type E820_RESERVED\n");
67                 return;
68         }
69
70         /* only a natively booted kernel should be using TXT */
71         if (paravirt_enabled()) {
72                 pr_warning("non-0 tboot_addr but pv_ops is enabled\n");
73                 return;
74         }
75
76         /* Map and check for tboot UUID. */
77         set_fixmap(FIX_TBOOT_BASE, boot_params.tboot_addr);
78         tboot = (struct tboot *)fix_to_virt(FIX_TBOOT_BASE);
79         if (memcmp(&tboot_uuid, &tboot->uuid, sizeof(tboot->uuid))) {
80                 pr_warning("tboot at 0x%llx is invalid\n",
81                            boot_params.tboot_addr);
82                 tboot = NULL;
83                 return;
84         }
85         if (tboot->version < 5) {
86                 pr_warning("tboot version is invalid: %u\n", tboot->version);
87                 tboot = NULL;
88                 return;
89         }
90
91         pr_info("found shared page at phys addr 0x%llx:\n",
92                 boot_params.tboot_addr);
93         pr_debug("version: %d\n", tboot->version);
94         pr_debug("log_addr: 0x%08x\n", tboot->log_addr);
95         pr_debug("shutdown_entry: 0x%x\n", tboot->shutdown_entry);
96         pr_debug("tboot_base: 0x%08x\n", tboot->tboot_base);
97         pr_debug("tboot_size: 0x%x\n", tboot->tboot_size);
98 }
99
100 static pgd_t *tboot_pg_dir;
101 static struct mm_struct tboot_mm = {
102         .mm_rb          = RB_ROOT,
103         .pgd            = swapper_pg_dir,
104         .mm_users       = ATOMIC_INIT(2),
105         .mm_count       = ATOMIC_INIT(1),
106         .mmap_sem       = __RWSEM_INITIALIZER(init_mm.mmap_sem),
107         .page_table_lock =  __SPIN_LOCK_UNLOCKED(init_mm.page_table_lock),
108         .mmlist         = LIST_HEAD_INIT(init_mm.mmlist),
109         .cpu_vm_mask    = CPU_MASK_ALL,
110 };
111
112 static inline void switch_to_tboot_pt(void)
113 {
114         write_cr3(virt_to_phys(tboot_pg_dir));
115 }
116
117 static int map_tboot_page(unsigned long vaddr, unsigned long pfn,
118                           pgprot_t prot)
119 {
120         pgd_t *pgd;
121         pud_t *pud;
122         pmd_t *pmd;
123         pte_t *pte;
124
125         pgd = pgd_offset(&tboot_mm, vaddr);
126         pud = pud_alloc(&tboot_mm, pgd, vaddr);
127         if (!pud)
128                 return -1;
129         pmd = pmd_alloc(&tboot_mm, pud, vaddr);
130         if (!pmd)
131                 return -1;
132         pte = pte_alloc_map(&tboot_mm, pmd, vaddr);
133         if (!pte)
134                 return -1;
135         set_pte_at(&tboot_mm, vaddr, pte, pfn_pte(pfn, prot));
136         pte_unmap(pte);
137         return 0;
138 }
139
140 static int map_tboot_pages(unsigned long vaddr, unsigned long start_pfn,
141                            unsigned long nr)
142 {
143         /* Reuse the original kernel mapping */
144         tboot_pg_dir = pgd_alloc(&tboot_mm);
145         if (!tboot_pg_dir)
146                 return -1;
147
148         for (; nr > 0; nr--, vaddr += PAGE_SIZE, start_pfn++) {
149                 if (map_tboot_page(vaddr, start_pfn, PAGE_KERNEL_EXEC))
150                         return -1;
151         }
152
153         return 0;
154 }
155
156 void tboot_create_trampoline(void)
157 {
158         u32 map_base, map_size;
159
160         if (!tboot_enabled())
161                 return;
162
163         /* Create identity map for tboot shutdown code. */
164         map_base = PFN_DOWN(tboot->tboot_base);
165         map_size = PFN_UP(tboot->tboot_size);
166         if (map_tboot_pages(map_base << PAGE_SHIFT, map_base, map_size))
167                 panic("tboot: Error mapping tboot pages (mfns) @ 0x%x, 0x%x\n", map_base, map_size);
168 }
169
170 static void set_mac_regions(void)
171 {
172         tboot->num_mac_regions = 3;
173         /* S3 resume code */
174         tboot->mac_regions[0].start = PFN_PHYS(PFN_DOWN(acpi_wakeup_address));
175         tboot->mac_regions[0].size = PFN_UP(WAKEUP_SIZE) << PAGE_SHIFT;
176         /* AP trampoline code */
177         tboot->mac_regions[1].start =
178                         PFN_PHYS(PFN_DOWN(virt_to_phys(trampoline_base)));
179         tboot->mac_regions[1].size = PFN_UP(TRAMPOLINE_SIZE) << PAGE_SHIFT;
180         /* kernel code + data + bss */
181         tboot->mac_regions[2].start = PFN_PHYS(PFN_DOWN(virt_to_phys(&_text)));
182         tboot->mac_regions[2].size = PFN_PHYS(PFN_UP(virt_to_phys(&_end))) -
183                                      PFN_PHYS(PFN_DOWN(virt_to_phys(&_text)));
184 }
185
186 void tboot_shutdown(u32 shutdown_type)
187 {
188         void (*shutdown)(void);
189
190         if (!tboot_enabled())
191                 return;
192
193         /*
194          * if we're being called before the 1:1 mapping is set up then just
195          * return and let the normal shutdown happen; this should only be
196          * due to very early panic()
197          */
198         if (!tboot_pg_dir)
199                 return;
200
201         /* if this is S3 then set regions to MAC */
202         if (shutdown_type == TB_SHUTDOWN_S3)
203                 set_mac_regions();
204
205         tboot->shutdown_type = shutdown_type;
206
207         switch_to_tboot_pt();
208
209         shutdown = (void(*)(void))(unsigned long)tboot->shutdown_entry;
210         shutdown();
211
212         /* should not reach here */
213         while (1)
214                 halt();
215 }
216
217 static void tboot_copy_fadt(const struct acpi_table_fadt *fadt)
218 {
219 #define TB_COPY_GAS(tbg, g)                     \
220         tbg.space_id     = g.space_id;          \
221         tbg.bit_width    = g.bit_width;         \
222         tbg.bit_offset   = g.bit_offset;        \
223         tbg.access_width = g.access_width;      \
224         tbg.address      = g.address;
225
226         TB_COPY_GAS(tboot->acpi_sinfo.pm1a_cnt_blk, fadt->xpm1a_control_block);
227         TB_COPY_GAS(tboot->acpi_sinfo.pm1b_cnt_blk, fadt->xpm1b_control_block);
228         TB_COPY_GAS(tboot->acpi_sinfo.pm1a_evt_blk, fadt->xpm1a_event_block);
229         TB_COPY_GAS(tboot->acpi_sinfo.pm1b_evt_blk, fadt->xpm1b_event_block);
230
231         /*
232          * We need phys addr of waking vector, but can't use virt_to_phys() on
233          * &acpi_gbl_FACS because it is ioremap'ed, so calc from FACS phys
234          * addr.
235          */
236         tboot->acpi_sinfo.wakeup_vector = fadt->facs +
237                 offsetof(struct acpi_table_facs, firmware_waking_vector);
238 }
239
240 void tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control)
241 {
242         static u32 acpi_shutdown_map[ACPI_S_STATE_COUNT] = {
243                 /* S0,1,2: */ -1, -1, -1,
244                 /* S3: */ TB_SHUTDOWN_S3,
245                 /* S4: */ TB_SHUTDOWN_S4,
246                 /* S5: */ TB_SHUTDOWN_S5 };
247
248         if (!tboot_enabled())
249                 return;
250
251         tboot_copy_fadt(&acpi_gbl_FADT);
252         tboot->acpi_sinfo.pm1a_cnt_val = pm1a_control;
253         tboot->acpi_sinfo.pm1b_cnt_val = pm1b_control;
254         /* we always use the 32b wakeup vector */
255         tboot->acpi_sinfo.vector_width = 32;
256         tboot->acpi_sinfo.kernel_s3_resume_vector = acpi_wakeup_address;
257
258         if (sleep_state >= ACPI_S_STATE_COUNT ||
259             acpi_shutdown_map[sleep_state] == -1) {
260                 pr_warning("unsupported sleep state 0x%x\n", sleep_state);
261                 return;
262         }
263
264         tboot_shutdown(acpi_shutdown_map[sleep_state]);
265 }
266
267 int tboot_wait_for_aps(int num_aps)
268 {
269         unsigned long timeout;
270
271         if (!tboot_enabled())
272                 return 0;
273
274         timeout = jiffies + AP_WAIT_TIMEOUT*HZ;
275         while (atomic_read((atomic_t *)&tboot->num_in_wfs) != num_aps &&
276                time_before(jiffies, timeout))
277                 cpu_relax();
278
279         return time_before(jiffies, timeout) ? 0 : 1;
280 }
281
282 /*
283  * TXT configuration registers (offsets from TXT_{PUB, PRIV}_CONFIG_REGS_BASE)
284  */
285
286 #define TXT_PUB_CONFIG_REGS_BASE       0xfed30000
287 #define TXT_PRIV_CONFIG_REGS_BASE      0xfed20000
288
289 /* # pages for each config regs space - used by fixmap */
290 #define NR_TXT_CONFIG_PAGES     ((TXT_PUB_CONFIG_REGS_BASE -                \
291                                   TXT_PRIV_CONFIG_REGS_BASE) >> PAGE_SHIFT)
292
293 /* offsets from pub/priv config space */
294 #define TXTCR_HEAP_BASE             0x0300
295 #define TXTCR_HEAP_SIZE             0x0308
296
297 #define SHA1_SIZE      20
298
299 struct sha1_hash {
300         u8 hash[SHA1_SIZE];
301 };
302
303 struct sinit_mle_data {
304         u32               version;             /* currently 6 */
305         struct sha1_hash  bios_acm_id;
306         u32               edx_senter_flags;
307         u64               mseg_valid;
308         struct sha1_hash  sinit_hash;
309         struct sha1_hash  mle_hash;
310         struct sha1_hash  stm_hash;
311         struct sha1_hash  lcp_policy_hash;
312         u32               lcp_policy_control;
313         u32               rlp_wakeup_addr;
314         u32               reserved;
315         u32               num_mdrs;
316         u32               mdrs_off;
317         u32               num_vtd_dmars;
318         u32               vtd_dmars_off;
319 } __packed;
320
321 struct acpi_table_header *tboot_get_dmar_table(struct acpi_table_header *dmar_tbl)
322 {
323         void *heap_base, *heap_ptr, *config;
324
325         if (!tboot_enabled())
326                 return dmar_tbl;
327
328         /*
329          * ACPI tables may not be DMA protected by tboot, so use DMAR copy
330          * SINIT saved in SinitMleData in TXT heap (which is DMA protected)
331          */
332
333         /* map config space in order to get heap addr */
334         config = ioremap(TXT_PUB_CONFIG_REGS_BASE, NR_TXT_CONFIG_PAGES *
335                          PAGE_SIZE);
336         if (!config)
337                 return NULL;
338
339         /* now map TXT heap */
340         heap_base = ioremap(*(u64 *)(config + TXTCR_HEAP_BASE),
341                             *(u64 *)(config + TXTCR_HEAP_SIZE));
342         iounmap(config);
343         if (!heap_base)
344                 return NULL;
345
346         /* walk heap to SinitMleData */
347         /* skip BiosData */
348         heap_ptr = heap_base + *(u64 *)heap_base;
349         /* skip OsMleData */
350         heap_ptr += *(u64 *)heap_ptr;
351         /* skip OsSinitData */
352         heap_ptr += *(u64 *)heap_ptr;
353         /* now points to SinitMleDataSize; set to SinitMleData */
354         heap_ptr += sizeof(u64);
355         /* get addr of DMAR table */
356         dmar_tbl = (struct acpi_table_header *)(heap_ptr +
357                    ((struct sinit_mle_data *)heap_ptr)->vtd_dmars_off -
358                    sizeof(u64));
359
360         /* don't unmap heap because dmar.c needs access to this */
361
362         return dmar_tbl;
363 }
364
365 int tboot_force_iommu(void)
366 {
367         if (!tboot_enabled())
368                 return 0;
369
370         if (no_iommu || swiotlb || dmar_disabled)
371                 pr_warning("Forcing Intel-IOMMU to enabled\n");
372
373         dmar_disabled = 0;
374 #ifdef CONFIG_SWIOTLB
375         swiotlb = 0;
376 #endif
377         no_iommu = 0;
378
379         return 1;
380 }