1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_X86_PARAVIRT_TYPES_H
3#define _ASM_X86_PARAVIRT_TYPES_H
4
5#ifdef CONFIG_PARAVIRT
6
7#ifndef __ASSEMBLER__
8#include <linux/types.h>
9
10#include <asm/desc_defs.h>
11#include <asm/pgtable_types.h>
12#include <asm/nospec-branch.h>
13
14struct page;
15struct thread_struct;
16struct desc_ptr;
17struct tss_struct;
18struct mm_struct;
19struct desc_struct;
20struct task_struct;
21struct cpumask;
22struct flush_tlb_info;
23struct mmu_gather;
24struct vm_area_struct;
25
26/*
27 * Wrapper type for pointers to code which uses the non-standard
28 * calling convention. See PV_CALL_SAVE_REGS_THUNK below.
29 */
30struct paravirt_callee_save {
31 void *func;
32};
33
34/* general info */
35struct pv_info {
36#ifdef CONFIG_PARAVIRT_XXL
37 u16 extra_user_64bit_cs; /* __USER_CS if none */
38#endif
39
40 const char *name;
41};
42
43#ifdef CONFIG_PARAVIRT_XXL
44struct pv_lazy_ops {
45 /* Set deferred update mode, used for batching operations. */
46 void (*enter)(void);
47 void (*leave)(void);
48 void (*flush)(void);
49} __no_randomize_layout;
50#endif
51
52struct pv_cpu_ops {
53 /* hooks for various privileged instructions */
54 void (*io_delay)(void);
55
56#ifdef CONFIG_PARAVIRT_XXL
57 unsigned long (*get_debugreg)(int regno);
58 void (*set_debugreg)(int regno, unsigned long value);
59
60 unsigned long (*read_cr0)(void);
61 void (*write_cr0)(unsigned long);
62
63 void (*write_cr4)(unsigned long);
64
65 /* Segment descriptor handling */
66 void (*load_tr_desc)(void);
67 void (*load_gdt)(const struct desc_ptr *);
68 void (*load_idt)(const struct desc_ptr *);
69 void (*set_ldt)(const void *desc, unsigned entries);
70 unsigned long (*store_tr)(void);
71 void (*load_tls)(struct thread_struct *t, unsigned int cpu);
72 void (*load_gs_index)(unsigned int idx);
73 void (*write_ldt_entry)(struct desc_struct *ldt, int entrynum,
74 const void *desc);
75 void (*write_gdt_entry)(struct desc_struct *,
76 int entrynum, const void *desc, int size);
77 void (*write_idt_entry)(gate_desc *,
78 int entrynum, const gate_desc *gate);
79 void (*alloc_ldt)(struct desc_struct *ldt, unsigned entries);
80 void (*free_ldt)(struct desc_struct *ldt, unsigned entries);
81
82 void (*load_sp0)(unsigned long sp0);
83
84#ifdef CONFIG_X86_IOPL_IOPERM
85 void (*invalidate_io_bitmap)(void);
86 void (*update_io_bitmap)(void);
87#endif
88
89 /* cpuid emulation, mostly so that caps bits can be disabled */
90 void (*cpuid)(unsigned int *eax, unsigned int *ebx,
91 unsigned int *ecx, unsigned int *edx);
92
93 /* Unsafe MSR operations. These will warn or panic on failure. */
94 u64 (*read_msr)(u32 msr);
95 void (*write_msr)(u32 msr, u64 val);
96
97 /*
98 * Safe MSR operations.
99 * Returns 0 or -EIO.
100 */
101 int (*read_msr_safe)(u32 msr, u64 *val);
102 int (*write_msr_safe)(u32 msr, u64 val);
103
104 u64 (*read_pmc)(int counter);
105
106 void (*start_context_switch)(struct task_struct *prev);
107 void (*end_context_switch)(struct task_struct *next);
108#endif
109} __no_randomize_layout;
110
111struct pv_irq_ops {
112#ifdef CONFIG_PARAVIRT_XXL
113 /*
114 * Get/set interrupt state. save_fl is expected to use X86_EFLAGS_IF;
115 * all other bits returned from save_fl are undefined.
116 *
117 * NOTE: These functions callers expect the callee to preserve
118 * more registers than the standard C calling convention.
119 */
120 struct paravirt_callee_save save_fl;
121 struct paravirt_callee_save irq_disable;
122 struct paravirt_callee_save irq_enable;
123#endif
124 void (*safe_halt)(void);
125 void (*halt)(void);
126} __no_randomize_layout;
127
128struct pv_mmu_ops {
129 /* TLB operations */
130 void (*flush_tlb_user)(void);
131 void (*flush_tlb_kernel)(void);
132 void (*flush_tlb_one_user)(unsigned long addr);
133 void (*flush_tlb_multi)(const struct cpumask *cpus,
134 const struct flush_tlb_info *info);
135
136 /* Hook for intercepting the destruction of an mm_struct. */
137 void (*exit_mmap)(struct mm_struct *mm);
138 void (*notify_page_enc_status_changed)(unsigned long pfn, int npages, bool enc);
139
140#ifdef CONFIG_PARAVIRT_XXL
141 struct paravirt_callee_save read_cr2;
142 void (*write_cr2)(unsigned long);
143
144 unsigned long (*read_cr3)(void);
145 void (*write_cr3)(unsigned long);
146
147 /* Hook for intercepting the creation/use of an mm_struct. */
148 void (*enter_mmap)(struct mm_struct *mm);
149
150 /* Hooks for allocating and freeing a pagetable top-level */
151 int (*pgd_alloc)(struct mm_struct *mm);
152 void (*pgd_free)(struct mm_struct *mm, pgd_t *pgd);
153
154 /*
155 * Hooks for allocating/releasing pagetable pages when they're
156 * attached to a pagetable
157 */
158 void (*alloc_pte)(struct mm_struct *mm, unsigned long pfn);
159 void (*alloc_pmd)(struct mm_struct *mm, unsigned long pfn);
160 void (*alloc_pud)(struct mm_struct *mm, unsigned long pfn);
161 void (*alloc_p4d)(struct mm_struct *mm, unsigned long pfn);
162 void (*release_pte)(unsigned long pfn);
163 void (*release_pmd)(unsigned long pfn);
164 void (*release_pud)(unsigned long pfn);
165 void (*release_p4d)(unsigned long pfn);
166
167 /* Pagetable manipulation functions */
168 void (*set_pte)(pte_t *ptep, pte_t pteval);
169 void (*set_pmd)(pmd_t *pmdp, pmd_t pmdval);
170
171 pte_t (*ptep_modify_prot_start)(struct vm_area_struct *vma, unsigned long addr,
172 pte_t *ptep);
173 void (*ptep_modify_prot_commit)(struct vm_area_struct *vma, unsigned long addr,
174 pte_t *ptep, pte_t pte);
175
176 struct paravirt_callee_save pte_val;
177 struct paravirt_callee_save make_pte;
178
179 struct paravirt_callee_save pgd_val;
180 struct paravirt_callee_save make_pgd;
181
182 void (*set_pud)(pud_t *pudp, pud_t pudval);
183
184 struct paravirt_callee_save pmd_val;
185 struct paravirt_callee_save make_pmd;
186
187 struct paravirt_callee_save pud_val;
188 struct paravirt_callee_save make_pud;
189
190 void (*set_p4d)(p4d_t *p4dp, p4d_t p4dval);
191
192 struct paravirt_callee_save p4d_val;
193 struct paravirt_callee_save make_p4d;
194
195 void (*set_pgd)(pgd_t *pgdp, pgd_t pgdval);
196
197 struct pv_lazy_ops lazy_mode;
198
199 /* dom0 ops */
200
201 /* Sometimes the physical address is a pfn, and sometimes its
202 an mfn. We can tell which is which from the index. */
203 void (*set_fixmap)(unsigned /* enum fixed_addresses */ idx,
204 phys_addr_t phys, pgprot_t flags);
205#endif
206} __no_randomize_layout;
207
208struct arch_spinlock;
209#ifdef CONFIG_SMP
210#include <asm/spinlock_types.h>
211#endif
212
213struct qspinlock;
214
215struct pv_lock_ops {
216 void (*queued_spin_lock_slowpath)(struct qspinlock *lock, u32 val);
217 struct paravirt_callee_save queued_spin_unlock;
218
219 void (*wait)(u8 *ptr, u8 val);
220 void (*kick)(int cpu);
221
222 struct paravirt_callee_save vcpu_is_preempted;
223} __no_randomize_layout;
224
225/* This contains all the paravirt structures: we get a convenient
226 * number for each function using the offset which we use to indicate
227 * what to patch. */
228struct paravirt_patch_template {
229 struct pv_cpu_ops cpu;
230 struct pv_irq_ops irq;
231 struct pv_mmu_ops mmu;
232 struct pv_lock_ops lock;
233} __no_randomize_layout;
234
235extern struct pv_info pv_info;
236extern struct paravirt_patch_template pv_ops;
237
238#define paravirt_ptr(op) [paravirt_opptr] "m" (pv_ops.op)
239
240/*
241 * This generates an indirect call based on the operation type number.
242 *
243 * Since alternatives run after enabling CET/IBT -- the latter setting/clearing
244 * capabilities and the former requiring all capabilities being finalized --
245 * these indirect calls are subject to IBT and the paravirt stubs should have
246 * ENDBR on.
247 *
248 * OTOH since this is effectively a __nocfi indirect call, the paravirt stubs
249 * don't need to bother with CFI prefixes.
250 */
251#define PARAVIRT_CALL \
252 ANNOTATE_RETPOLINE_SAFE \
253 "call *%[paravirt_opptr];"
254
255/*
256 * These macros are intended to wrap calls through one of the paravirt
257 * ops structs, so that they can be later identified and patched at
258 * runtime.
259 *
260 * Normally, a call to a pv_op function is a simple indirect call:
261 * (pv_op_struct.operations)(args...).
262 *
263 * Unfortunately, this is a relatively slow operation for modern CPUs,
264 * because it cannot necessarily determine what the destination
265 * address is. In this case, the address is a runtime constant, so at
266 * the very least we can patch the call to a simple direct call, or,
267 * ideally, patch an inline implementation into the callsite. (Direct
268 * calls are essentially free, because the call and return addresses
269 * are completely predictable.)
270 *
271 * For i386, these macros rely on the standard gcc "regparm(3)" calling
272 * convention, in which the first three arguments are placed in %eax,
273 * %edx, %ecx (in that order), and the remaining arguments are placed
274 * on the stack. All caller-save registers (eax,edx,ecx) are expected
275 * to be modified (either clobbered or used for return values).
276 * X86_64, on the other hand, already specifies a register-based calling
277 * conventions, returning at %rax, with parameters going in %rdi, %rsi,
278 * %rdx, and %rcx. Note that for this reason, x86_64 does not need any
279 * special handling for dealing with 4 arguments, unlike i386.
280 * However, x86_64 also has to clobber all caller saved registers, which
281 * unfortunately, are quite a bit (r8 - r11)
282 *
283 * Unfortunately there's no way to get gcc to generate the args setup
284 * for the call, and then allow the call itself to be generated by an
285 * inline asm. Because of this, we must do the complete arg setup and
286 * return value handling from within these macros. This is fairly
287 * cumbersome.
288 *
289 * There are 5 sets of PVOP_* macros for dealing with 0-4 arguments.
290 * It could be extended to more arguments, but there would be little
291 * to be gained from that. For each number of arguments, there are
292 * two VCALL and CALL variants for void and non-void functions.
293 *
294 * When there is a return value, the invoker of the macro must specify
295 * the return type. The macro then uses sizeof() on that type to
296 * determine whether it's a 32 or 64 bit value and places the return
297 * in the right register(s) (just %eax for 32-bit, and %edx:%eax for
298 * 64-bit). For x86_64 machines, it just returns in %rax regardless of
299 * the return value size.
300 *
301 * 64-bit arguments are passed as a pair of adjacent 32-bit arguments;
302 * i386 also passes 64-bit arguments as a pair of adjacent 32-bit arguments
303 * in low,high order
304 *
305 * Small structures are passed and returned in registers. The macro
306 * calling convention can't directly deal with this, so the wrapper
307 * functions must do it.
308 *
309 * These PVOP_* macros are only defined within this header. This
310 * means that all uses must be wrapped in inline functions. This also
311 * makes sure the incoming and outgoing types are always correct.
312 */
313#ifdef CONFIG_X86_32
314#define PVOP_CALL_ARGS \
315 unsigned long __eax = __eax, __edx = __edx, __ecx = __ecx;
316
317#define PVOP_CALL_ARG1(x) "a" ((unsigned long)(x))
318#define PVOP_CALL_ARG2(x) "d" ((unsigned long)(x))
319#define PVOP_CALL_ARG3(x) "c" ((unsigned long)(x))
320
321#define PVOP_VCALL_CLOBBERS "=a" (__eax), "=d" (__edx), \
322 "=c" (__ecx)
323#define PVOP_CALL_CLOBBERS PVOP_VCALL_CLOBBERS
324
325#define PVOP_VCALLEE_CLOBBERS "=a" (__eax), "=d" (__edx)
326#define PVOP_CALLEE_CLOBBERS PVOP_VCALLEE_CLOBBERS
327
328#define EXTRA_CLOBBERS
329#define VEXTRA_CLOBBERS
330#else /* CONFIG_X86_64 */
331/* [re]ax isn't an arg, but the return val */
332#define PVOP_CALL_ARGS \
333 unsigned long __edi = __edi, __esi = __esi, \
334 __edx = __edx, __ecx = __ecx, __eax = __eax;
335
336#define PVOP_CALL_ARG1(x) "D" ((unsigned long)(x))
337#define PVOP_CALL_ARG2(x) "S" ((unsigned long)(x))
338#define PVOP_CALL_ARG3(x) "d" ((unsigned long)(x))
339#define PVOP_CALL_ARG4(x) "c" ((unsigned long)(x))
340
341#define PVOP_VCALL_CLOBBERS "=D" (__edi), \
342 "=S" (__esi), "=d" (__edx), \
343 "=c" (__ecx)
344#define PVOP_CALL_CLOBBERS PVOP_VCALL_CLOBBERS, "=a" (__eax)
345
346/*
347 * void functions are still allowed [re]ax for scratch.
348 *
349 * The ZERO_CALL_USED REGS feature may end up zeroing out callee-saved
350 * registers. Make sure we model this with the appropriate clobbers.
351 */
352#ifdef CONFIG_ZERO_CALL_USED_REGS
353#define PVOP_VCALLEE_CLOBBERS "=a" (__eax), PVOP_VCALL_CLOBBERS
354#else
355#define PVOP_VCALLEE_CLOBBERS "=a" (__eax)
356#endif
357#define PVOP_CALLEE_CLOBBERS PVOP_VCALLEE_CLOBBERS
358
359#define EXTRA_CLOBBERS , "r8", "r9", "r10", "r11"
360#define VEXTRA_CLOBBERS , "rax", "r8", "r9", "r10", "r11"
361#endif /* CONFIG_X86_32 */
362
363#ifdef CONFIG_PARAVIRT_DEBUG
364#define PVOP_TEST_NULL(op) BUG_ON(pv_ops.op == NULL)
365#else
366#define PVOP_TEST_NULL(op) ((void)pv_ops.op)
367#endif
368
369#define PVOP_RETVAL(rettype) \
370 ({ unsigned long __mask = ~0UL; \
371 BUILD_BUG_ON(sizeof(rettype) > sizeof(unsigned long)); \
372 switch (sizeof(rettype)) { \
373 case 1: __mask = 0xffUL; break; \
374 case 2: __mask = 0xffffUL; break; \
375 case 4: __mask = 0xffffffffUL; break; \
376 default: break; \
377 } \
378 __mask & __eax; \
379 })
380
381/*
382 * Use alternative patching for paravirt calls:
383 * - For replacing an indirect call with a direct one, use the "normal"
384 * ALTERNATIVE() macro with the indirect call as the initial code sequence,
385 * which will be replaced with the related direct call by using the
386 * ALT_FLAG_DIRECT_CALL special case and the "always on" feature.
387 * - In case the replacement is either a direct call or a short code sequence
388 * depending on a feature bit, the ALTERNATIVE_2() macro is being used.
389 * The indirect call is the initial code sequence again, while the special
390 * code sequence is selected with the specified feature bit. In case the
391 * feature is not active, the direct call is used as above via the
392 * ALT_FLAG_DIRECT_CALL special case and the "always on" feature.
393 */
394#define ____PVOP_CALL(ret, op, call_clbr, extra_clbr, ...) \
395 ({ \
396 PVOP_CALL_ARGS; \
397 PVOP_TEST_NULL(op); \
398 asm volatile(ALTERNATIVE(PARAVIRT_CALL, ALT_CALL_INSTR, \
399 ALT_CALL_ALWAYS) \
400 : call_clbr, ASM_CALL_CONSTRAINT \
401 : paravirt_ptr(op), \
402 ##__VA_ARGS__ \
403 : "memory", "cc" extra_clbr); \
404 ret; \
405 })
406
407#define ____PVOP_ALT_CALL(ret, op, alt, cond, call_clbr, \
408 extra_clbr, ...) \
409 ({ \
410 PVOP_CALL_ARGS; \
411 PVOP_TEST_NULL(op); \
412 asm volatile(ALTERNATIVE_2(PARAVIRT_CALL, \
413 ALT_CALL_INSTR, ALT_CALL_ALWAYS, \
414 alt, cond) \
415 : call_clbr, ASM_CALL_CONSTRAINT \
416 : paravirt_ptr(op), \
417 ##__VA_ARGS__ \
418 : "memory", "cc" extra_clbr); \
419 ret; \
420 })
421
422#define __PVOP_CALL(rettype, op, ...) \
423 ____PVOP_CALL(PVOP_RETVAL(rettype), op, \
424 PVOP_CALL_CLOBBERS, EXTRA_CLOBBERS, ##__VA_ARGS__)
425
426#define __PVOP_ALT_CALL(rettype, op, alt, cond, ...) \
427 ____PVOP_ALT_CALL(PVOP_RETVAL(rettype), op, alt, cond, \
428 PVOP_CALL_CLOBBERS, EXTRA_CLOBBERS, \
429 ##__VA_ARGS__)
430
431#define __PVOP_CALLEESAVE(rettype, op, ...) \
432 ____PVOP_CALL(PVOP_RETVAL(rettype), op.func, \
433 PVOP_CALLEE_CLOBBERS, , ##__VA_ARGS__)
434
435#define __PVOP_ALT_CALLEESAVE(rettype, op, alt, cond, ...) \
436 ____PVOP_ALT_CALL(PVOP_RETVAL(rettype), op.func, alt, cond, \
437 PVOP_CALLEE_CLOBBERS, , ##__VA_ARGS__)
438
439
440#define __PVOP_VCALL(op, ...) \
441 (void)____PVOP_CALL(, op, PVOP_VCALL_CLOBBERS, \
442 VEXTRA_CLOBBERS, ##__VA_ARGS__)
443
444#define __PVOP_ALT_VCALL(op, alt, cond, ...) \
445 (void)____PVOP_ALT_CALL(, op, alt, cond, \
446 PVOP_VCALL_CLOBBERS, VEXTRA_CLOBBERS, \
447 ##__VA_ARGS__)
448
449#define __PVOP_VCALLEESAVE(op, ...) \
450 (void)____PVOP_CALL(, op.func, \
451 PVOP_VCALLEE_CLOBBERS, , ##__VA_ARGS__)
452
453#define __PVOP_ALT_VCALLEESAVE(op, alt, cond, ...) \
454 (void)____PVOP_ALT_CALL(, op.func, alt, cond, \
455 PVOP_VCALLEE_CLOBBERS, , ##__VA_ARGS__)
456
457
458#define PVOP_CALL0(rettype, op) \
459 __PVOP_CALL(rettype, op)
460#define PVOP_VCALL0(op) \
461 __PVOP_VCALL(op)
462#define PVOP_ALT_CALL0(rettype, op, alt, cond) \
463 __PVOP_ALT_CALL(rettype, op, alt, cond)
464#define PVOP_ALT_VCALL0(op, alt, cond) \
465 __PVOP_ALT_VCALL(op, alt, cond)
466
467#define PVOP_CALLEE0(rettype, op) \
468 __PVOP_CALLEESAVE(rettype, op)
469#define PVOP_VCALLEE0(op) \
470 __PVOP_VCALLEESAVE(op)
471#define PVOP_ALT_CALLEE0(rettype, op, alt, cond) \
472 __PVOP_ALT_CALLEESAVE(rettype, op, alt, cond)
473#define PVOP_ALT_VCALLEE0(op, alt, cond) \
474 __PVOP_ALT_VCALLEESAVE(op, alt, cond)
475
476
477#define PVOP_CALL1(rettype, op, arg1) \
478 __PVOP_CALL(rettype, op, PVOP_CALL_ARG1(arg1))
479#define PVOP_VCALL1(op, arg1) \
480 __PVOP_VCALL(op, PVOP_CALL_ARG1(arg1))
481#define PVOP_ALT_VCALL1(op, arg1, alt, cond) \
482 __PVOP_ALT_VCALL(op, alt, cond, PVOP_CALL_ARG1(arg1))
483
484#define PVOP_CALLEE1(rettype, op, arg1) \
485 __PVOP_CALLEESAVE(rettype, op, PVOP_CALL_ARG1(arg1))
486#define PVOP_VCALLEE1(op, arg1) \
487 __PVOP_VCALLEESAVE(op, PVOP_CALL_ARG1(arg1))
488#define PVOP_ALT_CALLEE1(rettype, op, arg1, alt, cond) \
489 __PVOP_ALT_CALLEESAVE(rettype, op, alt, cond, PVOP_CALL_ARG1(arg1))
490#define PVOP_ALT_VCALLEE1(op, arg1, alt, cond) \
491 __PVOP_ALT_VCALLEESAVE(op, alt, cond, PVOP_CALL_ARG1(arg1))
492
493
494#define PVOP_CALL2(rettype, op, arg1, arg2) \
495 __PVOP_CALL(rettype, op, PVOP_CALL_ARG1(arg1), PVOP_CALL_ARG2(arg2))
496#define PVOP_VCALL2(op, arg1, arg2) \
497 __PVOP_VCALL(op, PVOP_CALL_ARG1(arg1), PVOP_CALL_ARG2(arg2))
498
499#define PVOP_CALL3(rettype, op, arg1, arg2, arg3) \
500 __PVOP_CALL(rettype, op, PVOP_CALL_ARG1(arg1), \
501 PVOP_CALL_ARG2(arg2), PVOP_CALL_ARG3(arg3))
502#define PVOP_VCALL3(op, arg1, arg2, arg3) \
503 __PVOP_VCALL(op, PVOP_CALL_ARG1(arg1), \
504 PVOP_CALL_ARG2(arg2), PVOP_CALL_ARG3(arg3))
505
506#define PVOP_CALL4(rettype, op, arg1, arg2, arg3, arg4) \
507 __PVOP_CALL(rettype, op, \
508 PVOP_CALL_ARG1(arg1), PVOP_CALL_ARG2(arg2), \
509 PVOP_CALL_ARG3(arg3), PVOP_CALL_ARG4(arg4))
510#define PVOP_VCALL4(op, arg1, arg2, arg3, arg4) \
511 __PVOP_VCALL(op, PVOP_CALL_ARG1(arg1), PVOP_CALL_ARG2(arg2), \
512 PVOP_CALL_ARG3(arg3), PVOP_CALL_ARG4(arg4))
513
514unsigned long paravirt_ret0(void);
515#ifdef CONFIG_PARAVIRT_XXL
516u64 _paravirt_ident_64(u64);
517unsigned long pv_native_save_fl(void);
518void pv_native_irq_disable(void);
519void pv_native_irq_enable(void);
520unsigned long pv_native_read_cr2(void);
521#endif
522
523#define paravirt_nop ((void *)nop_func)
524
525#endif /* __ASSEMBLER__ */
526
527#define ALT_NOT_XEN ALT_NOT(X86_FEATURE_XENPV)
528
529#endif /* CONFIG_PARAVIRT */
530#endif /* _ASM_X86_PARAVIRT_TYPES_H */
531

source code of linux/arch/x86/include/asm/paravirt_types.h