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1/*
2 * Machine specific setup for xen
3 *
4 * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
5 */
6
7#include <linux/module.h>
8#include <linux/sched.h>
9#include <linux/mm.h>
10#include <linux/pm.h>
11#include <linux/memblock.h>
12#include <linux/cpuidle.h>
13
14#include <asm/elf.h>
15#include <asm/vdso.h>
16#include <asm/e820.h>
17#include <asm/setup.h>
18#include <asm/acpi.h>
19#include <asm/xen/hypervisor.h>
20#include <asm/xen/hypercall.h>
21
22#include <xen/xen.h>
23#include <xen/page.h>
24#include <xen/interface/callback.h>
25#include <xen/interface/memory.h>
26#include <xen/interface/physdev.h>
27#include <xen/features.h>
28
29#include "xen-ops.h"
30#include "vdso.h"
31
32/* These are code, but not functions. Defined in entry.S */
33extern const char xen_hypervisor_callback[];
34extern const char xen_failsafe_callback[];
35extern void xen_sysenter_target(void);
36extern void xen_syscall_target(void);
37extern void xen_syscall32_target(void);
38
39/* Amount of extra memory space we add to the e820 ranges */
40phys_addr_t xen_extra_mem_start, xen_extra_mem_size;
41
42/*
43 * The maximum amount of extra memory compared to the base size. The
44 * main scaling factor is the size of struct page. At extreme ratios
45 * of base:extra, all the base memory can be filled with page
46 * structures for the extra memory, leaving no space for anything
47 * else.
48 *
49 * 10x seems like a reasonable balance between scaling flexibility and
50 * leaving a practically usable system.
51 */
52#define EXTRA_MEM_RATIO (10)
53
54static void __init xen_add_extra_mem(unsigned long pages)
55{
56 unsigned long pfn;
57
58 u64 size = (u64)pages * PAGE_SIZE;
59 u64 extra_start = xen_extra_mem_start + xen_extra_mem_size;
60
61 if (!pages)
62 return;
63
64 e820_add_region(extra_start, size, E820_RAM);
65 sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
66
67 memblock_x86_reserve_range(extra_start, extra_start + size, "XEN EXTRA");
68
69 xen_extra_mem_size += size;
70
71 xen_max_p2m_pfn = PFN_DOWN(extra_start + size);
72
73 for (pfn = PFN_DOWN(extra_start); pfn <= xen_max_p2m_pfn; pfn++)
74 __set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
75}
76
77static unsigned long __init xen_release_chunk(phys_addr_t start_addr,
78 phys_addr_t end_addr)
79{
80 struct xen_memory_reservation reservation = {
81 .address_bits = 0,
82 .extent_order = 0,
83 .domid = DOMID_SELF
84 };
85 unsigned long start, end;
86 unsigned long len = 0;
87 unsigned long pfn;
88 int ret;
89
90 start = PFN_UP(start_addr);
91 end = PFN_DOWN(end_addr);
92
93 if (end <= start)
94 return 0;
95
96 for(pfn = start; pfn < end; pfn++) {
97 unsigned long mfn = pfn_to_mfn(pfn);
98
99 /* Make sure pfn exists to start with */
100 if (mfn == INVALID_P2M_ENTRY || mfn_to_pfn(mfn) != pfn)
101 continue;
102
103 set_xen_guest_handle(reservation.extent_start, &mfn);
104 reservation.nr_extents = 1;
105
106 ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation,
107 &reservation);
108 WARN(ret != 1, "Failed to release pfn %lx err=%d\n", pfn, ret);
109 if (ret == 1) {
110 __set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
111 len++;
112 }
113 }
114 printk(KERN_INFO "Freeing %lx-%lx pfn range: %lu pages freed\n",
115 start, end, len);
116
117 return len;
118}
119
120static unsigned long __init xen_return_unused_memory(unsigned long max_pfn,
121 const struct e820map *e820)
122{
123 phys_addr_t max_addr = PFN_PHYS(max_pfn);
124 phys_addr_t last_end = ISA_END_ADDRESS;
125 unsigned long released = 0;
126 int i;
127
128 /* Free any unused memory above the low 1Mbyte. */
129 for (i = 0; i < e820->nr_map && last_end < max_addr; i++) {
130 phys_addr_t end = e820->map[i].addr;
131 end = min(max_addr, end);
132
133 if (last_end < end)
134 released += xen_release_chunk(last_end, end);
135 last_end = max(last_end, e820->map[i].addr + e820->map[i].size);
136 }
137
138 if (last_end < max_addr)
139 released += xen_release_chunk(last_end, max_addr);
140
141 printk(KERN_INFO "released %lu pages of unused memory\n", released);
142 return released;
143}
144
145static unsigned long __init xen_set_identity(const struct e820entry *list,
146 ssize_t map_size)
147{
148 phys_addr_t last = xen_initial_domain() ? 0 : ISA_END_ADDRESS;
149 phys_addr_t start_pci = last;
150 const struct e820entry *entry;
151 unsigned long identity = 0;
152 int i;
153
154 for (i = 0, entry = list; i < map_size; i++, entry++) {
155 phys_addr_t start = entry->addr;
156 phys_addr_t end = start + entry->size;
157
158 if (start < last)
159 start = last;
160
161 if (end <= start)
162 continue;
163
164 /* Skip over the 1MB region. */
165 if (last > end)
166 continue;
167
168 if ((entry->type == E820_RAM) || (entry->type == E820_UNUSABLE)) {
169 if (start > start_pci)
170 identity += set_phys_range_identity(
171 PFN_UP(start_pci), PFN_DOWN(start));
172
173 /* Without saving 'last' we would gooble RAM too
174 * at the end of the loop. */
175 last = end;
176 start_pci = end;
177 continue;
178 }
179 start_pci = min(start, start_pci);
180 last = end;
181 }
182 if (last > start_pci)
183 identity += set_phys_range_identity(
184 PFN_UP(start_pci), PFN_DOWN(last));
185 return identity;
186}
187
188static unsigned long __init xen_get_max_pages(void)
189{
190 unsigned long max_pages = MAX_DOMAIN_PAGES;
191 domid_t domid = DOMID_SELF;
192 int ret;
193
194 ret = HYPERVISOR_memory_op(XENMEM_maximum_reservation, &domid);
195 if (ret > 0)
196 max_pages = ret;
197 return min(max_pages, MAX_DOMAIN_PAGES);
198}
199
200/**
201 * machine_specific_memory_setup - Hook for machine specific memory setup.
202 **/
203char * __init xen_memory_setup(void)
204{
205 static struct e820entry map[E820MAX] __initdata;
206 static struct e820entry map_raw[E820MAX] __initdata;
207
208 unsigned long max_pfn = xen_start_info->nr_pages;
209 unsigned long long mem_end;
210 int rc;
211 struct xen_memory_map memmap;
212 unsigned long extra_pages = 0;
213 unsigned long extra_limit;
214 unsigned long identity_pages = 0;
215 int i;
216 int op;
217
218 max_pfn = min(MAX_DOMAIN_PAGES, max_pfn);
219 mem_end = PFN_PHYS(max_pfn);
220
221 memmap.nr_entries = E820MAX;
222 set_xen_guest_handle(memmap.buffer, map);
223
224 op = xen_initial_domain() ?
225 XENMEM_machine_memory_map :
226 XENMEM_memory_map;
227 rc = HYPERVISOR_memory_op(op, &memmap);
228 if (rc == -ENOSYS) {
229 BUG_ON(xen_initial_domain());
230 memmap.nr_entries = 1;
231 map[0].addr = 0ULL;
232 map[0].size = mem_end;
233 /* 8MB slack (to balance backend allocations). */
234 map[0].size += 8ULL << 20;
235 map[0].type = E820_RAM;
236 rc = 0;
237 }
238 BUG_ON(rc);
239
240 memcpy(map_raw, map, sizeof(map));
241 e820.nr_map = 0;
242 xen_extra_mem_start = mem_end;
243 for (i = 0; i < memmap.nr_entries; i++) {
244 unsigned long long end;
245
246 /* Guard against non-page aligned E820 entries. */
247 if (map[i].type == E820_RAM)
248 map[i].size -= (map[i].size + map[i].addr) % PAGE_SIZE;
249
250 end = map[i].addr + map[i].size;
251 if (map[i].type == E820_RAM && end > mem_end) {
252 /* RAM off the end - may be partially included */
253 u64 delta = min(map[i].size, end - mem_end);
254
255 map[i].size -= delta;
256 end -= delta;
257
258 extra_pages += PFN_DOWN(delta);
259 /*
260 * Set RAM below 4GB that is not for us to be unusable.
261 * This prevents "System RAM" address space from being
262 * used as potential resource for I/O address (happens
263 * when 'allocate_resource' is called).
264 */
265 if (delta &&
266 (xen_initial_domain() && end < 0x100000000ULL))
267 e820_add_region(end, delta, E820_UNUSABLE);
268 }
269
270 if (map[i].size > 0 && end > xen_extra_mem_start)
271 xen_extra_mem_start = end;
272
273 /* Add region if any remains */
274 if (map[i].size > 0)
275 e820_add_region(map[i].addr, map[i].size, map[i].type);
276 }
277 /* Align the balloon area so that max_low_pfn does not get set
278 * to be at the _end_ of the PCI gap at the far end (fee01000).
279 * Note that xen_extra_mem_start gets set in the loop above to be
280 * past the last E820 region. */
281 if (xen_initial_domain() && (xen_extra_mem_start < (1ULL<<32)))
282 xen_extra_mem_start = (1ULL<<32);
283
284 /*
285 * In domU, the ISA region is normal, usable memory, but we
286 * reserve ISA memory anyway because too many things poke
287 * about in there.
288 *
289 * In Dom0, the host E820 information can leave gaps in the
290 * ISA range, which would cause us to release those pages. To
291 * avoid this, we unconditionally reserve them here.
292 */
293 e820_add_region(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS,
294 E820_RESERVED);
295
296 /*
297 * Reserve Xen bits:
298 * - mfn_list
299 * - xen_start_info
300 * See comment above "struct start_info" in <xen/interface/xen.h>
301 */
302 memblock_x86_reserve_range(__pa(xen_start_info->mfn_list),
303 __pa(xen_start_info->pt_base),
304 "XEN START INFO");
305
306 sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
307
308 extra_limit = xen_get_max_pages();
309 if (max_pfn + extra_pages > extra_limit) {
310 if (extra_limit > max_pfn)
311 extra_pages = extra_limit - max_pfn;
312 else
313 extra_pages = 0;
314 }
315
316 extra_pages += xen_return_unused_memory(xen_start_info->nr_pages, &e820);
317
318 /*
319 * Clamp the amount of extra memory to a EXTRA_MEM_RATIO
320 * factor the base size. On non-highmem systems, the base
321 * size is the full initial memory allocation; on highmem it
322 * is limited to the max size of lowmem, so that it doesn't
323 * get completely filled.
324 *
325 * In principle there could be a problem in lowmem systems if
326 * the initial memory is also very large with respect to
327 * lowmem, but we won't try to deal with that here.
328 */
329 extra_limit = min(EXTRA_MEM_RATIO * min(max_pfn, PFN_DOWN(MAXMEM)),
330 max_pfn + extra_pages);
331
332 if (extra_limit >= max_pfn)
333 extra_pages = extra_limit - max_pfn;
334 else
335 extra_pages = 0;
336
337 xen_add_extra_mem(extra_pages);
338
339 /*
340 * Set P2M for all non-RAM pages and E820 gaps to be identity
341 * type PFNs. We supply it with the non-sanitized version
342 * of the E820.
343 */
344 identity_pages = xen_set_identity(map_raw, memmap.nr_entries);
345 printk(KERN_INFO "Set %ld page(s) to 1-1 mapping.\n", identity_pages);
346 return "Xen";
347}
348
349/*
350 * Set the bit indicating "nosegneg" library variants should be used.
351 * We only need to bother in pure 32-bit mode; compat 32-bit processes
352 * can have un-truncated segments, so wrapping around is allowed.
353 */
354static void __init fiddle_vdso(void)
355{
356#ifdef CONFIG_X86_32
357 u32 *mask;
358 mask = VDSO32_SYMBOL(&vdso32_int80_start, NOTE_MASK);
359 *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
360 mask = VDSO32_SYMBOL(&vdso32_sysenter_start, NOTE_MASK);
361 *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
362#endif
363}
364
365static int __cpuinit register_callback(unsigned type, const void *func)
366{
367 struct callback_register callback = {
368 .type = type,
369 .address = XEN_CALLBACK(__KERNEL_CS, func),
370 .flags = CALLBACKF_mask_events,
371 };
372
373 return HYPERVISOR_callback_op(CALLBACKOP_register, &callback);
374}
375
376void __cpuinit xen_enable_sysenter(void)
377{
378 int ret;
379 unsigned sysenter_feature;
380
381#ifdef CONFIG_X86_32
382 sysenter_feature = X86_FEATURE_SEP;
383#else
384 sysenter_feature = X86_FEATURE_SYSENTER32;
385#endif
386
387 if (!boot_cpu_has(sysenter_feature))
388 return;
389
390 ret = register_callback(CALLBACKTYPE_sysenter, xen_sysenter_target);
391 if(ret != 0)
392 setup_clear_cpu_cap(sysenter_feature);
393}
394
395void __cpuinit xen_enable_syscall(void)
396{
397#ifdef CONFIG_X86_64
398 int ret;
399
400 ret = register_callback(CALLBACKTYPE_syscall, xen_syscall_target);
401 if (ret != 0) {
402 printk(KERN_ERR "Failed to set syscall callback: %d\n", ret);
403 /* Pretty fatal; 64-bit userspace has no other
404 mechanism for syscalls. */
405 }
406
407 if (boot_cpu_has(X86_FEATURE_SYSCALL32)) {
408 ret = register_callback(CALLBACKTYPE_syscall32,
409 xen_syscall32_target);
410 if (ret != 0)
411 setup_clear_cpu_cap(X86_FEATURE_SYSCALL32);
412 }
413#endif /* CONFIG_X86_64 */
414}
415
416void __init xen_arch_setup(void)
417{
418 xen_panic_handler_init();
419
420 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments);
421 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables);
422
423 if (!xen_feature(XENFEAT_auto_translated_physmap))
424 HYPERVISOR_vm_assist(VMASST_CMD_enable,
425 VMASST_TYPE_pae_extended_cr3);
426
427 if (register_callback(CALLBACKTYPE_event, xen_hypervisor_callback) ||
428 register_callback(CALLBACKTYPE_failsafe, xen_failsafe_callback))
429 BUG();
430
431 xen_enable_sysenter();
432 xen_enable_syscall();
433
434#ifdef CONFIG_ACPI
435 if (!(xen_start_info->flags & SIF_INITDOMAIN)) {
436 printk(KERN_INFO "ACPI in unprivileged domain disabled\n");
437 disable_acpi();
438 }
439#endif
440
441 memcpy(boot_command_line, xen_start_info->cmd_line,
442 MAX_GUEST_CMDLINE > COMMAND_LINE_SIZE ?
443 COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE);
444
445 /* Set up idle, making sure it calls safe_halt() pvop */
446#ifdef CONFIG_X86_32
447 boot_cpu_data.hlt_works_ok = 1;
448#endif
449 disable_cpuidle();
450 boot_option_idle_override = IDLE_HALT;
451
452 fiddle_vdso();
453}
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Machine specific setup for xen
4 *
5 * Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
6 */
7
8#include <linux/init.h>
9#include <linux/sched.h>
10#include <linux/kstrtox.h>
11#include <linux/mm.h>
12#include <linux/pm.h>
13#include <linux/memblock.h>
14#include <linux/cpuidle.h>
15#include <linux/cpufreq.h>
16#include <linux/memory_hotplug.h>
17
18#include <asm/elf.h>
19#include <asm/vdso.h>
20#include <asm/e820/api.h>
21#include <asm/setup.h>
22#include <asm/acpi.h>
23#include <asm/numa.h>
24#include <asm/idtentry.h>
25#include <asm/xen/hypervisor.h>
26#include <asm/xen/hypercall.h>
27
28#include <xen/xen.h>
29#include <xen/page.h>
30#include <xen/interface/callback.h>
31#include <xen/interface/memory.h>
32#include <xen/interface/physdev.h>
33#include <xen/features.h>
34#include <xen/hvc-console.h>
35#include "xen-ops.h"
36#include "mmu.h"
37
38#define GB(x) ((uint64_t)(x) * 1024 * 1024 * 1024)
39
40/* Amount of extra memory space we add to the e820 ranges */
41struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata;
42
43/* Number of pages released from the initial allocation. */
44unsigned long xen_released_pages;
45
46/* E820 map used during setting up memory. */
47static struct e820_table xen_e820_table __initdata;
48
49/*
50 * Buffer used to remap identity mapped pages. We only need the virtual space.
51 * The physical page behind this address is remapped as needed to different
52 * buffer pages.
53 */
54#define REMAP_SIZE (P2M_PER_PAGE - 3)
55static struct {
56 unsigned long next_area_mfn;
57 unsigned long target_pfn;
58 unsigned long size;
59 unsigned long mfns[REMAP_SIZE];
60} xen_remap_buf __initdata __aligned(PAGE_SIZE);
61static unsigned long xen_remap_mfn __initdata = INVALID_P2M_ENTRY;
62
63/*
64 * The maximum amount of extra memory compared to the base size. The
65 * main scaling factor is the size of struct page. At extreme ratios
66 * of base:extra, all the base memory can be filled with page
67 * structures for the extra memory, leaving no space for anything
68 * else.
69 *
70 * 10x seems like a reasonable balance between scaling flexibility and
71 * leaving a practically usable system.
72 */
73#define EXTRA_MEM_RATIO (10)
74
75static bool xen_512gb_limit __initdata = IS_ENABLED(CONFIG_XEN_512GB);
76
77static void __init xen_parse_512gb(void)
78{
79 bool val = false;
80 char *arg;
81
82 arg = strstr(xen_start_info->cmd_line, "xen_512gb_limit");
83 if (!arg)
84 return;
85
86 arg = strstr(xen_start_info->cmd_line, "xen_512gb_limit=");
87 if (!arg)
88 val = true;
89 else if (kstrtobool(arg + strlen("xen_512gb_limit="), &val))
90 return;
91
92 xen_512gb_limit = val;
93}
94
95static void __init xen_add_extra_mem(unsigned long start_pfn,
96 unsigned long n_pfns)
97{
98 int i;
99
100 /*
101 * No need to check for zero size, should happen rarely and will only
102 * write a new entry regarded to be unused due to zero size.
103 */
104 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
105 /* Add new region. */
106 if (xen_extra_mem[i].n_pfns == 0) {
107 xen_extra_mem[i].start_pfn = start_pfn;
108 xen_extra_mem[i].n_pfns = n_pfns;
109 break;
110 }
111 /* Append to existing region. */
112 if (xen_extra_mem[i].start_pfn + xen_extra_mem[i].n_pfns ==
113 start_pfn) {
114 xen_extra_mem[i].n_pfns += n_pfns;
115 break;
116 }
117 }
118 if (i == XEN_EXTRA_MEM_MAX_REGIONS)
119 printk(KERN_WARNING "Warning: not enough extra memory regions\n");
120
121 memblock_reserve(PFN_PHYS(start_pfn), PFN_PHYS(n_pfns));
122}
123
124static void __init xen_del_extra_mem(unsigned long start_pfn,
125 unsigned long n_pfns)
126{
127 int i;
128 unsigned long start_r, size_r;
129
130 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
131 start_r = xen_extra_mem[i].start_pfn;
132 size_r = xen_extra_mem[i].n_pfns;
133
134 /* Start of region. */
135 if (start_r == start_pfn) {
136 BUG_ON(n_pfns > size_r);
137 xen_extra_mem[i].start_pfn += n_pfns;
138 xen_extra_mem[i].n_pfns -= n_pfns;
139 break;
140 }
141 /* End of region. */
142 if (start_r + size_r == start_pfn + n_pfns) {
143 BUG_ON(n_pfns > size_r);
144 xen_extra_mem[i].n_pfns -= n_pfns;
145 break;
146 }
147 /* Mid of region. */
148 if (start_pfn > start_r && start_pfn < start_r + size_r) {
149 BUG_ON(start_pfn + n_pfns > start_r + size_r);
150 xen_extra_mem[i].n_pfns = start_pfn - start_r;
151 /* Calling memblock_reserve() again is okay. */
152 xen_add_extra_mem(start_pfn + n_pfns, start_r + size_r -
153 (start_pfn + n_pfns));
154 break;
155 }
156 }
157 memblock_phys_free(PFN_PHYS(start_pfn), PFN_PHYS(n_pfns));
158}
159
160/*
161 * Called during boot before the p2m list can take entries beyond the
162 * hypervisor supplied p2m list. Entries in extra mem are to be regarded as
163 * invalid.
164 */
165unsigned long __ref xen_chk_extra_mem(unsigned long pfn)
166{
167 int i;
168
169 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
170 if (pfn >= xen_extra_mem[i].start_pfn &&
171 pfn < xen_extra_mem[i].start_pfn + xen_extra_mem[i].n_pfns)
172 return INVALID_P2M_ENTRY;
173 }
174
175 return IDENTITY_FRAME(pfn);
176}
177
178/*
179 * Mark all pfns of extra mem as invalid in p2m list.
180 */
181void __init xen_inv_extra_mem(void)
182{
183 unsigned long pfn, pfn_s, pfn_e;
184 int i;
185
186 for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) {
187 if (!xen_extra_mem[i].n_pfns)
188 continue;
189 pfn_s = xen_extra_mem[i].start_pfn;
190 pfn_e = pfn_s + xen_extra_mem[i].n_pfns;
191 for (pfn = pfn_s; pfn < pfn_e; pfn++)
192 set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
193 }
194}
195
196/*
197 * Finds the next RAM pfn available in the E820 map after min_pfn.
198 * This function updates min_pfn with the pfn found and returns
199 * the size of that range or zero if not found.
200 */
201static unsigned long __init xen_find_pfn_range(unsigned long *min_pfn)
202{
203 const struct e820_entry *entry = xen_e820_table.entries;
204 unsigned int i;
205 unsigned long done = 0;
206
207 for (i = 0; i < xen_e820_table.nr_entries; i++, entry++) {
208 unsigned long s_pfn;
209 unsigned long e_pfn;
210
211 if (entry->type != E820_TYPE_RAM)
212 continue;
213
214 e_pfn = PFN_DOWN(entry->addr + entry->size);
215
216 /* We only care about E820 after this */
217 if (e_pfn <= *min_pfn)
218 continue;
219
220 s_pfn = PFN_UP(entry->addr);
221
222 /* If min_pfn falls within the E820 entry, we want to start
223 * at the min_pfn PFN.
224 */
225 if (s_pfn <= *min_pfn) {
226 done = e_pfn - *min_pfn;
227 } else {
228 done = e_pfn - s_pfn;
229 *min_pfn = s_pfn;
230 }
231 break;
232 }
233
234 return done;
235}
236
237static int __init xen_free_mfn(unsigned long mfn)
238{
239 struct xen_memory_reservation reservation = {
240 .address_bits = 0,
241 .extent_order = 0,
242 .domid = DOMID_SELF
243 };
244
245 set_xen_guest_handle(reservation.extent_start, &mfn);
246 reservation.nr_extents = 1;
247
248 return HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation);
249}
250
251/*
252 * This releases a chunk of memory and then does the identity map. It's used
253 * as a fallback if the remapping fails.
254 */
255static void __init xen_set_identity_and_release_chunk(unsigned long start_pfn,
256 unsigned long end_pfn, unsigned long nr_pages)
257{
258 unsigned long pfn, end;
259 int ret;
260
261 WARN_ON(start_pfn > end_pfn);
262
263 /* Release pages first. */
264 end = min(end_pfn, nr_pages);
265 for (pfn = start_pfn; pfn < end; pfn++) {
266 unsigned long mfn = pfn_to_mfn(pfn);
267
268 /* Make sure pfn exists to start with */
269 if (mfn == INVALID_P2M_ENTRY || mfn_to_pfn(mfn) != pfn)
270 continue;
271
272 ret = xen_free_mfn(mfn);
273 WARN(ret != 1, "Failed to release pfn %lx err=%d\n", pfn, ret);
274
275 if (ret == 1) {
276 xen_released_pages++;
277 if (!__set_phys_to_machine(pfn, INVALID_P2M_ENTRY))
278 break;
279 } else
280 break;
281 }
282
283 set_phys_range_identity(start_pfn, end_pfn);
284}
285
286/*
287 * Helper function to update the p2m and m2p tables and kernel mapping.
288 */
289static void __init xen_update_mem_tables(unsigned long pfn, unsigned long mfn)
290{
291 struct mmu_update update = {
292 .ptr = ((uint64_t)mfn << PAGE_SHIFT) | MMU_MACHPHYS_UPDATE,
293 .val = pfn
294 };
295
296 /* Update p2m */
297 if (!set_phys_to_machine(pfn, mfn)) {
298 WARN(1, "Failed to set p2m mapping for pfn=%ld mfn=%ld\n",
299 pfn, mfn);
300 BUG();
301 }
302
303 /* Update m2p */
304 if (HYPERVISOR_mmu_update(&update, 1, NULL, DOMID_SELF) < 0) {
305 WARN(1, "Failed to set m2p mapping for mfn=%ld pfn=%ld\n",
306 mfn, pfn);
307 BUG();
308 }
309
310 if (HYPERVISOR_update_va_mapping((unsigned long)__va(pfn << PAGE_SHIFT),
311 mfn_pte(mfn, PAGE_KERNEL), 0)) {
312 WARN(1, "Failed to update kernel mapping for mfn=%ld pfn=%ld\n",
313 mfn, pfn);
314 BUG();
315 }
316}
317
318/*
319 * This function updates the p2m and m2p tables with an identity map from
320 * start_pfn to start_pfn+size and prepares remapping the underlying RAM of the
321 * original allocation at remap_pfn. The information needed for remapping is
322 * saved in the memory itself to avoid the need for allocating buffers. The
323 * complete remap information is contained in a list of MFNs each containing
324 * up to REMAP_SIZE MFNs and the start target PFN for doing the remap.
325 * This enables us to preserve the original mfn sequence while doing the
326 * remapping at a time when the memory management is capable of allocating
327 * virtual and physical memory in arbitrary amounts, see 'xen_remap_memory' and
328 * its callers.
329 */
330static void __init xen_do_set_identity_and_remap_chunk(
331 unsigned long start_pfn, unsigned long size, unsigned long remap_pfn)
332{
333 unsigned long buf = (unsigned long)&xen_remap_buf;
334 unsigned long mfn_save, mfn;
335 unsigned long ident_pfn_iter, remap_pfn_iter;
336 unsigned long ident_end_pfn = start_pfn + size;
337 unsigned long left = size;
338 unsigned int i, chunk;
339
340 WARN_ON(size == 0);
341
342 mfn_save = virt_to_mfn(buf);
343
344 for (ident_pfn_iter = start_pfn, remap_pfn_iter = remap_pfn;
345 ident_pfn_iter < ident_end_pfn;
346 ident_pfn_iter += REMAP_SIZE, remap_pfn_iter += REMAP_SIZE) {
347 chunk = (left < REMAP_SIZE) ? left : REMAP_SIZE;
348
349 /* Map first pfn to xen_remap_buf */
350 mfn = pfn_to_mfn(ident_pfn_iter);
351 set_pte_mfn(buf, mfn, PAGE_KERNEL);
352
353 /* Save mapping information in page */
354 xen_remap_buf.next_area_mfn = xen_remap_mfn;
355 xen_remap_buf.target_pfn = remap_pfn_iter;
356 xen_remap_buf.size = chunk;
357 for (i = 0; i < chunk; i++)
358 xen_remap_buf.mfns[i] = pfn_to_mfn(ident_pfn_iter + i);
359
360 /* Put remap buf into list. */
361 xen_remap_mfn = mfn;
362
363 /* Set identity map */
364 set_phys_range_identity(ident_pfn_iter, ident_pfn_iter + chunk);
365
366 left -= chunk;
367 }
368
369 /* Restore old xen_remap_buf mapping */
370 set_pte_mfn(buf, mfn_save, PAGE_KERNEL);
371}
372
373/*
374 * This function takes a contiguous pfn range that needs to be identity mapped
375 * and:
376 *
377 * 1) Finds a new range of pfns to use to remap based on E820 and remap_pfn.
378 * 2) Calls the do_ function to actually do the mapping/remapping work.
379 *
380 * The goal is to not allocate additional memory but to remap the existing
381 * pages. In the case of an error the underlying memory is simply released back
382 * to Xen and not remapped.
383 */
384static unsigned long __init xen_set_identity_and_remap_chunk(
385 unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages,
386 unsigned long remap_pfn)
387{
388 unsigned long pfn;
389 unsigned long i = 0;
390 unsigned long n = end_pfn - start_pfn;
391
392 if (remap_pfn == 0)
393 remap_pfn = nr_pages;
394
395 while (i < n) {
396 unsigned long cur_pfn = start_pfn + i;
397 unsigned long left = n - i;
398 unsigned long size = left;
399 unsigned long remap_range_size;
400
401 /* Do not remap pages beyond the current allocation */
402 if (cur_pfn >= nr_pages) {
403 /* Identity map remaining pages */
404 set_phys_range_identity(cur_pfn, cur_pfn + size);
405 break;
406 }
407 if (cur_pfn + size > nr_pages)
408 size = nr_pages - cur_pfn;
409
410 remap_range_size = xen_find_pfn_range(&remap_pfn);
411 if (!remap_range_size) {
412 pr_warn("Unable to find available pfn range, not remapping identity pages\n");
413 xen_set_identity_and_release_chunk(cur_pfn,
414 cur_pfn + left, nr_pages);
415 break;
416 }
417 /* Adjust size to fit in current e820 RAM region */
418 if (size > remap_range_size)
419 size = remap_range_size;
420
421 xen_do_set_identity_and_remap_chunk(cur_pfn, size, remap_pfn);
422
423 /* Update variables to reflect new mappings. */
424 i += size;
425 remap_pfn += size;
426 }
427
428 /*
429 * If the PFNs are currently mapped, their VA mappings need to be
430 * zapped.
431 */
432 for (pfn = start_pfn; pfn <= max_pfn_mapped && pfn < end_pfn; pfn++)
433 (void)HYPERVISOR_update_va_mapping(
434 (unsigned long)__va(pfn << PAGE_SHIFT),
435 native_make_pte(0), 0);
436
437 return remap_pfn;
438}
439
440static unsigned long __init xen_count_remap_pages(
441 unsigned long start_pfn, unsigned long end_pfn, unsigned long nr_pages,
442 unsigned long remap_pages)
443{
444 if (start_pfn >= nr_pages)
445 return remap_pages;
446
447 return remap_pages + min(end_pfn, nr_pages) - start_pfn;
448}
449
450static unsigned long __init xen_foreach_remap_area(unsigned long nr_pages,
451 unsigned long (*func)(unsigned long start_pfn, unsigned long end_pfn,
452 unsigned long nr_pages, unsigned long last_val))
453{
454 phys_addr_t start = 0;
455 unsigned long ret_val = 0;
456 const struct e820_entry *entry = xen_e820_table.entries;
457 int i;
458
459 /*
460 * Combine non-RAM regions and gaps until a RAM region (or the
461 * end of the map) is reached, then call the provided function
462 * to perform its duty on the non-RAM region.
463 *
464 * The combined non-RAM regions are rounded to a whole number
465 * of pages so any partial pages are accessible via the 1:1
466 * mapping. This is needed for some BIOSes that put (for
467 * example) the DMI tables in a reserved region that begins on
468 * a non-page boundary.
469 */
470 for (i = 0; i < xen_e820_table.nr_entries; i++, entry++) {
471 phys_addr_t end = entry->addr + entry->size;
472 if (entry->type == E820_TYPE_RAM || i == xen_e820_table.nr_entries - 1) {
473 unsigned long start_pfn = PFN_DOWN(start);
474 unsigned long end_pfn = PFN_UP(end);
475
476 if (entry->type == E820_TYPE_RAM)
477 end_pfn = PFN_UP(entry->addr);
478
479 if (start_pfn < end_pfn)
480 ret_val = func(start_pfn, end_pfn, nr_pages,
481 ret_val);
482 start = end;
483 }
484 }
485
486 return ret_val;
487}
488
489/*
490 * Remap the memory prepared in xen_do_set_identity_and_remap_chunk().
491 * The remap information (which mfn remap to which pfn) is contained in the
492 * to be remapped memory itself in a linked list anchored at xen_remap_mfn.
493 * This scheme allows to remap the different chunks in arbitrary order while
494 * the resulting mapping will be independent from the order.
495 */
496void __init xen_remap_memory(void)
497{
498 unsigned long buf = (unsigned long)&xen_remap_buf;
499 unsigned long mfn_save, pfn;
500 unsigned long remapped = 0;
501 unsigned int i;
502 unsigned long pfn_s = ~0UL;
503 unsigned long len = 0;
504
505 mfn_save = virt_to_mfn(buf);
506
507 while (xen_remap_mfn != INVALID_P2M_ENTRY) {
508 /* Map the remap information */
509 set_pte_mfn(buf, xen_remap_mfn, PAGE_KERNEL);
510
511 BUG_ON(xen_remap_mfn != xen_remap_buf.mfns[0]);
512
513 pfn = xen_remap_buf.target_pfn;
514 for (i = 0; i < xen_remap_buf.size; i++) {
515 xen_update_mem_tables(pfn, xen_remap_buf.mfns[i]);
516 remapped++;
517 pfn++;
518 }
519 if (pfn_s == ~0UL || pfn == pfn_s) {
520 pfn_s = xen_remap_buf.target_pfn;
521 len += xen_remap_buf.size;
522 } else if (pfn_s + len == xen_remap_buf.target_pfn) {
523 len += xen_remap_buf.size;
524 } else {
525 xen_del_extra_mem(pfn_s, len);
526 pfn_s = xen_remap_buf.target_pfn;
527 len = xen_remap_buf.size;
528 }
529 xen_remap_mfn = xen_remap_buf.next_area_mfn;
530 }
531
532 if (pfn_s != ~0UL && len)
533 xen_del_extra_mem(pfn_s, len);
534
535 set_pte_mfn(buf, mfn_save, PAGE_KERNEL);
536
537 pr_info("Remapped %ld page(s)\n", remapped);
538}
539
540static unsigned long __init xen_get_pages_limit(void)
541{
542 unsigned long limit;
543
544 limit = MAXMEM / PAGE_SIZE;
545 if (!xen_initial_domain() && xen_512gb_limit)
546 limit = GB(512) / PAGE_SIZE;
547
548 return limit;
549}
550
551static unsigned long __init xen_get_max_pages(void)
552{
553 unsigned long max_pages, limit;
554 domid_t domid = DOMID_SELF;
555 long ret;
556
557 limit = xen_get_pages_limit();
558 max_pages = limit;
559
560 /*
561 * For the initial domain we use the maximum reservation as
562 * the maximum page.
563 *
564 * For guest domains the current maximum reservation reflects
565 * the current maximum rather than the static maximum. In this
566 * case the e820 map provided to us will cover the static
567 * maximum region.
568 */
569 if (xen_initial_domain()) {
570 ret = HYPERVISOR_memory_op(XENMEM_maximum_reservation, &domid);
571 if (ret > 0)
572 max_pages = ret;
573 }
574
575 return min(max_pages, limit);
576}
577
578static void __init xen_align_and_add_e820_region(phys_addr_t start,
579 phys_addr_t size, int type)
580{
581 phys_addr_t end = start + size;
582
583 /* Align RAM regions to page boundaries. */
584 if (type == E820_TYPE_RAM) {
585 start = PAGE_ALIGN(start);
586 end &= ~((phys_addr_t)PAGE_SIZE - 1);
587#ifdef CONFIG_MEMORY_HOTPLUG
588 /*
589 * Don't allow adding memory not in E820 map while booting the
590 * system. Once the balloon driver is up it will remove that
591 * restriction again.
592 */
593 max_mem_size = end;
594#endif
595 }
596
597 e820__range_add(start, end - start, type);
598}
599
600static void __init xen_ignore_unusable(void)
601{
602 struct e820_entry *entry = xen_e820_table.entries;
603 unsigned int i;
604
605 for (i = 0; i < xen_e820_table.nr_entries; i++, entry++) {
606 if (entry->type == E820_TYPE_UNUSABLE)
607 entry->type = E820_TYPE_RAM;
608 }
609}
610
611bool __init xen_is_e820_reserved(phys_addr_t start, phys_addr_t size)
612{
613 struct e820_entry *entry;
614 unsigned mapcnt;
615 phys_addr_t end;
616
617 if (!size)
618 return false;
619
620 end = start + size;
621 entry = xen_e820_table.entries;
622
623 for (mapcnt = 0; mapcnt < xen_e820_table.nr_entries; mapcnt++) {
624 if (entry->type == E820_TYPE_RAM && entry->addr <= start &&
625 (entry->addr + entry->size) >= end)
626 return false;
627
628 entry++;
629 }
630
631 return true;
632}
633
634/*
635 * Find a free area in physical memory not yet reserved and compliant with
636 * E820 map.
637 * Used to relocate pre-allocated areas like initrd or p2m list which are in
638 * conflict with the to be used E820 map.
639 * In case no area is found, return 0. Otherwise return the physical address
640 * of the area which is already reserved for convenience.
641 */
642phys_addr_t __init xen_find_free_area(phys_addr_t size)
643{
644 unsigned mapcnt;
645 phys_addr_t addr, start;
646 struct e820_entry *entry = xen_e820_table.entries;
647
648 for (mapcnt = 0; mapcnt < xen_e820_table.nr_entries; mapcnt++, entry++) {
649 if (entry->type != E820_TYPE_RAM || entry->size < size)
650 continue;
651 start = entry->addr;
652 for (addr = start; addr < start + size; addr += PAGE_SIZE) {
653 if (!memblock_is_reserved(addr))
654 continue;
655 start = addr + PAGE_SIZE;
656 if (start + size > entry->addr + entry->size)
657 break;
658 }
659 if (addr >= start + size) {
660 memblock_reserve(start, size);
661 return start;
662 }
663 }
664
665 return 0;
666}
667
668/*
669 * Like memcpy, but with physical addresses for dest and src.
670 */
671static void __init xen_phys_memcpy(phys_addr_t dest, phys_addr_t src,
672 phys_addr_t n)
673{
674 phys_addr_t dest_off, src_off, dest_len, src_len, len;
675 void *from, *to;
676
677 while (n) {
678 dest_off = dest & ~PAGE_MASK;
679 src_off = src & ~PAGE_MASK;
680 dest_len = n;
681 if (dest_len > (NR_FIX_BTMAPS << PAGE_SHIFT) - dest_off)
682 dest_len = (NR_FIX_BTMAPS << PAGE_SHIFT) - dest_off;
683 src_len = n;
684 if (src_len > (NR_FIX_BTMAPS << PAGE_SHIFT) - src_off)
685 src_len = (NR_FIX_BTMAPS << PAGE_SHIFT) - src_off;
686 len = min(dest_len, src_len);
687 to = early_memremap(dest - dest_off, dest_len + dest_off);
688 from = early_memremap(src - src_off, src_len + src_off);
689 memcpy(to, from, len);
690 early_memunmap(to, dest_len + dest_off);
691 early_memunmap(from, src_len + src_off);
692 n -= len;
693 dest += len;
694 src += len;
695 }
696}
697
698/*
699 * Reserve Xen mfn_list.
700 */
701static void __init xen_reserve_xen_mfnlist(void)
702{
703 phys_addr_t start, size;
704
705 if (xen_start_info->mfn_list >= __START_KERNEL_map) {
706 start = __pa(xen_start_info->mfn_list);
707 size = PFN_ALIGN(xen_start_info->nr_pages *
708 sizeof(unsigned long));
709 } else {
710 start = PFN_PHYS(xen_start_info->first_p2m_pfn);
711 size = PFN_PHYS(xen_start_info->nr_p2m_frames);
712 }
713
714 memblock_reserve(start, size);
715 if (!xen_is_e820_reserved(start, size))
716 return;
717
718 xen_relocate_p2m();
719 memblock_phys_free(start, size);
720}
721
722/**
723 * xen_memory_setup - Hook for machine specific memory setup.
724 **/
725char * __init xen_memory_setup(void)
726{
727 unsigned long max_pfn, pfn_s, n_pfns;
728 phys_addr_t mem_end, addr, size, chunk_size;
729 u32 type;
730 int rc;
731 struct xen_memory_map memmap;
732 unsigned long max_pages;
733 unsigned long extra_pages = 0;
734 int i;
735 int op;
736
737 xen_parse_512gb();
738 max_pfn = xen_get_pages_limit();
739 max_pfn = min(max_pfn, xen_start_info->nr_pages);
740 mem_end = PFN_PHYS(max_pfn);
741
742 memmap.nr_entries = ARRAY_SIZE(xen_e820_table.entries);
743 set_xen_guest_handle(memmap.buffer, xen_e820_table.entries);
744
745#if defined(CONFIG_MEMORY_HOTPLUG) && defined(CONFIG_XEN_BALLOON)
746 xen_saved_max_mem_size = max_mem_size;
747#endif
748
749 op = xen_initial_domain() ?
750 XENMEM_machine_memory_map :
751 XENMEM_memory_map;
752 rc = HYPERVISOR_memory_op(op, &memmap);
753 if (rc == -ENOSYS) {
754 BUG_ON(xen_initial_domain());
755 memmap.nr_entries = 1;
756 xen_e820_table.entries[0].addr = 0ULL;
757 xen_e820_table.entries[0].size = mem_end;
758 /* 8MB slack (to balance backend allocations). */
759 xen_e820_table.entries[0].size += 8ULL << 20;
760 xen_e820_table.entries[0].type = E820_TYPE_RAM;
761 rc = 0;
762 }
763 BUG_ON(rc);
764 BUG_ON(memmap.nr_entries == 0);
765 xen_e820_table.nr_entries = memmap.nr_entries;
766
767 /*
768 * Xen won't allow a 1:1 mapping to be created to UNUSABLE
769 * regions, so if we're using the machine memory map leave the
770 * region as RAM as it is in the pseudo-physical map.
771 *
772 * UNUSABLE regions in domUs are not handled and will need
773 * a patch in the future.
774 */
775 if (xen_initial_domain())
776 xen_ignore_unusable();
777
778 /* Make sure the Xen-supplied memory map is well-ordered. */
779 e820__update_table(&xen_e820_table);
780
781 max_pages = xen_get_max_pages();
782
783 /* How many extra pages do we need due to remapping? */
784 max_pages += xen_foreach_remap_area(max_pfn, xen_count_remap_pages);
785
786 if (max_pages > max_pfn)
787 extra_pages += max_pages - max_pfn;
788
789 /*
790 * Clamp the amount of extra memory to a EXTRA_MEM_RATIO
791 * factor the base size.
792 *
793 * Make sure we have no memory above max_pages, as this area
794 * isn't handled by the p2m management.
795 */
796 extra_pages = min3(EXTRA_MEM_RATIO * min(max_pfn, PFN_DOWN(MAXMEM)),
797 extra_pages, max_pages - max_pfn);
798 i = 0;
799 addr = xen_e820_table.entries[0].addr;
800 size = xen_e820_table.entries[0].size;
801 while (i < xen_e820_table.nr_entries) {
802 bool discard = false;
803
804 chunk_size = size;
805 type = xen_e820_table.entries[i].type;
806
807 if (type == E820_TYPE_RAM) {
808 if (addr < mem_end) {
809 chunk_size = min(size, mem_end - addr);
810 } else if (extra_pages) {
811 chunk_size = min(size, PFN_PHYS(extra_pages));
812 pfn_s = PFN_UP(addr);
813 n_pfns = PFN_DOWN(addr + chunk_size) - pfn_s;
814 extra_pages -= n_pfns;
815 xen_add_extra_mem(pfn_s, n_pfns);
816 xen_max_p2m_pfn = pfn_s + n_pfns;
817 } else
818 discard = true;
819 }
820
821 if (!discard)
822 xen_align_and_add_e820_region(addr, chunk_size, type);
823
824 addr += chunk_size;
825 size -= chunk_size;
826 if (size == 0) {
827 i++;
828 if (i < xen_e820_table.nr_entries) {
829 addr = xen_e820_table.entries[i].addr;
830 size = xen_e820_table.entries[i].size;
831 }
832 }
833 }
834
835 /*
836 * Set the rest as identity mapped, in case PCI BARs are
837 * located here.
838 */
839 set_phys_range_identity(addr / PAGE_SIZE, ~0ul);
840
841 /*
842 * In domU, the ISA region is normal, usable memory, but we
843 * reserve ISA memory anyway because too many things poke
844 * about in there.
845 */
846 e820__range_add(ISA_START_ADDRESS, ISA_END_ADDRESS - ISA_START_ADDRESS, E820_TYPE_RESERVED);
847
848 e820__update_table(e820_table);
849
850 /*
851 * Check whether the kernel itself conflicts with the target E820 map.
852 * Failing now is better than running into weird problems later due
853 * to relocating (and even reusing) pages with kernel text or data.
854 */
855 if (xen_is_e820_reserved(__pa_symbol(_text),
856 __pa_symbol(__bss_stop) - __pa_symbol(_text))) {
857 xen_raw_console_write("Xen hypervisor allocated kernel memory conflicts with E820 map\n");
858 BUG();
859 }
860
861 /*
862 * Check for a conflict of the hypervisor supplied page tables with
863 * the target E820 map.
864 */
865 xen_pt_check_e820();
866
867 xen_reserve_xen_mfnlist();
868
869 /* Check for a conflict of the initrd with the target E820 map. */
870 if (xen_is_e820_reserved(boot_params.hdr.ramdisk_image,
871 boot_params.hdr.ramdisk_size)) {
872 phys_addr_t new_area, start, size;
873
874 new_area = xen_find_free_area(boot_params.hdr.ramdisk_size);
875 if (!new_area) {
876 xen_raw_console_write("Can't find new memory area for initrd needed due to E820 map conflict\n");
877 BUG();
878 }
879
880 start = boot_params.hdr.ramdisk_image;
881 size = boot_params.hdr.ramdisk_size;
882 xen_phys_memcpy(new_area, start, size);
883 pr_info("initrd moved from [mem %#010llx-%#010llx] to [mem %#010llx-%#010llx]\n",
884 start, start + size, new_area, new_area + size);
885 memblock_phys_free(start, size);
886 boot_params.hdr.ramdisk_image = new_area;
887 boot_params.ext_ramdisk_image = new_area >> 32;
888 }
889
890 /*
891 * Set identity map on non-RAM pages and prepare remapping the
892 * underlying RAM.
893 */
894 xen_foreach_remap_area(max_pfn, xen_set_identity_and_remap_chunk);
895
896 pr_info("Released %ld page(s)\n", xen_released_pages);
897
898 return "Xen";
899}
900
901static int register_callback(unsigned type, const void *func)
902{
903 struct callback_register callback = {
904 .type = type,
905 .address = XEN_CALLBACK(__KERNEL_CS, func),
906 .flags = CALLBACKF_mask_events,
907 };
908
909 return HYPERVISOR_callback_op(CALLBACKOP_register, &callback);
910}
911
912void xen_enable_sysenter(void)
913{
914 if (cpu_feature_enabled(X86_FEATURE_SYSENTER32) &&
915 register_callback(CALLBACKTYPE_sysenter, xen_entry_SYSENTER_compat))
916 setup_clear_cpu_cap(X86_FEATURE_SYSENTER32);
917}
918
919void xen_enable_syscall(void)
920{
921 int ret;
922
923 ret = register_callback(CALLBACKTYPE_syscall, xen_entry_SYSCALL_64);
924 if (ret != 0) {
925 printk(KERN_ERR "Failed to set syscall callback: %d\n", ret);
926 /* Pretty fatal; 64-bit userspace has no other
927 mechanism for syscalls. */
928 }
929
930 if (cpu_feature_enabled(X86_FEATURE_SYSCALL32) &&
931 register_callback(CALLBACKTYPE_syscall32, xen_entry_SYSCALL_compat))
932 setup_clear_cpu_cap(X86_FEATURE_SYSCALL32);
933}
934
935static void __init xen_pvmmu_arch_setup(void)
936{
937 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments);
938 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_writable_pagetables);
939
940 HYPERVISOR_vm_assist(VMASST_CMD_enable,
941 VMASST_TYPE_pae_extended_cr3);
942
943 if (register_callback(CALLBACKTYPE_event,
944 xen_asm_exc_xen_hypervisor_callback) ||
945 register_callback(CALLBACKTYPE_failsafe, xen_failsafe_callback))
946 BUG();
947
948 xen_enable_sysenter();
949 xen_enable_syscall();
950}
951
952/* This function is not called for HVM domains */
953void __init xen_arch_setup(void)
954{
955 xen_panic_handler_init();
956 xen_pvmmu_arch_setup();
957
958#ifdef CONFIG_ACPI
959 if (!(xen_start_info->flags & SIF_INITDOMAIN)) {
960 printk(KERN_INFO "ACPI in unprivileged domain disabled\n");
961 disable_acpi();
962 }
963#endif
964
965 memcpy(boot_command_line, xen_start_info->cmd_line,
966 MAX_GUEST_CMDLINE > COMMAND_LINE_SIZE ?
967 COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE);
968
969 /* Set up idle, making sure it calls safe_halt() pvop */
970 disable_cpuidle();
971 disable_cpufreq();
972 WARN_ON(xen_set_default_idle());
973#ifdef CONFIG_NUMA
974 numa_off = 1;
975#endif
976}