xref: /openbmc/qemu/include/exec/exec-all.h (revision e7b79428)
1 /*
2  * internal execution defines for qemu
3  *
4  *  Copyright (c) 2003 Fabrice Bellard
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #ifndef EXEC_ALL_H
21 #define EXEC_ALL_H
22 
23 #include "cpu.h"
24 #ifdef CONFIG_TCG
25 #include "exec/cpu_ldst.h"
26 #endif
27 
28 /* allow to see translation results - the slowdown should be negligible, so we leave it */
29 #define DEBUG_DISAS
30 
31 /* Page tracking code uses ram addresses in system mode, and virtual
32    addresses in userspace mode.  Define tb_page_addr_t to be an appropriate
33    type.  */
34 #if defined(CONFIG_USER_ONLY)
35 typedef abi_ulong tb_page_addr_t;
36 #define TB_PAGE_ADDR_FMT TARGET_ABI_FMT_lx
37 #else
38 typedef ram_addr_t tb_page_addr_t;
39 #define TB_PAGE_ADDR_FMT RAM_ADDR_FMT
40 #endif
41 
42 void gen_intermediate_code(CPUState *cpu, TranslationBlock *tb, int max_insns);
43 void restore_state_to_opc(CPUArchState *env, TranslationBlock *tb,
44                           target_ulong *data);
45 
46 /**
47  * cpu_restore_state:
48  * @cpu: the vCPU state is to be restore to
49  * @searched_pc: the host PC the fault occurred at
50  * @will_exit: true if the TB executed will be interrupted after some
51                cpu adjustments. Required for maintaining the correct
52                icount valus
53  * @return: true if state was restored, false otherwise
54  *
55  * Attempt to restore the state for a fault occurring in translated
56  * code. If the searched_pc is not in translated code no state is
57  * restored and the function returns false.
58  */
59 bool cpu_restore_state(CPUState *cpu, uintptr_t searched_pc, bool will_exit);
60 
61 void QEMU_NORETURN cpu_loop_exit_noexc(CPUState *cpu);
62 void QEMU_NORETURN cpu_loop_exit(CPUState *cpu);
63 void QEMU_NORETURN cpu_loop_exit_restore(CPUState *cpu, uintptr_t pc);
64 void QEMU_NORETURN cpu_loop_exit_atomic(CPUState *cpu, uintptr_t pc);
65 
66 /**
67  * cpu_loop_exit_requested:
68  * @cpu: The CPU state to be tested
69  *
70  * Indicate if somebody asked for a return of the CPU to the main loop
71  * (e.g., via cpu_exit() or cpu_interrupt()).
72  *
73  * This is helpful for architectures that support interruptible
74  * instructions. After writing back all state to registers/memory, this
75  * call can be used to check if it makes sense to return to the main loop
76  * or to continue executing the interruptible instruction.
77  */
78 static inline bool cpu_loop_exit_requested(CPUState *cpu)
79 {
80     return (int32_t)qatomic_read(&cpu_neg(cpu)->icount_decr.u32) < 0;
81 }
82 
83 #if !defined(CONFIG_USER_ONLY) && defined(CONFIG_TCG)
84 /* cputlb.c */
85 /**
86  * tlb_init - initialize a CPU's TLB
87  * @cpu: CPU whose TLB should be initialized
88  */
89 void tlb_init(CPUState *cpu);
90 /**
91  * tlb_destroy - destroy a CPU's TLB
92  * @cpu: CPU whose TLB should be destroyed
93  */
94 void tlb_destroy(CPUState *cpu);
95 /**
96  * tlb_flush_page:
97  * @cpu: CPU whose TLB should be flushed
98  * @addr: virtual address of page to be flushed
99  *
100  * Flush one page from the TLB of the specified CPU, for all
101  * MMU indexes.
102  */
103 void tlb_flush_page(CPUState *cpu, target_ulong addr);
104 /**
105  * tlb_flush_page_all_cpus:
106  * @cpu: src CPU of the flush
107  * @addr: virtual address of page to be flushed
108  *
109  * Flush one page from the TLB of the specified CPU, for all
110  * MMU indexes.
111  */
112 void tlb_flush_page_all_cpus(CPUState *src, target_ulong addr);
113 /**
114  * tlb_flush_page_all_cpus_synced:
115  * @cpu: src CPU of the flush
116  * @addr: virtual address of page to be flushed
117  *
118  * Flush one page from the TLB of the specified CPU, for all MMU
119  * indexes like tlb_flush_page_all_cpus except the source vCPUs work
120  * is scheduled as safe work meaning all flushes will be complete once
121  * the source vCPUs safe work is complete. This will depend on when
122  * the guests translation ends the TB.
123  */
124 void tlb_flush_page_all_cpus_synced(CPUState *src, target_ulong addr);
125 /**
126  * tlb_flush:
127  * @cpu: CPU whose TLB should be flushed
128  *
129  * Flush the entire TLB for the specified CPU. Most CPU architectures
130  * allow the implementation to drop entries from the TLB at any time
131  * so this is generally safe. If more selective flushing is required
132  * use one of the other functions for efficiency.
133  */
134 void tlb_flush(CPUState *cpu);
135 /**
136  * tlb_flush_all_cpus:
137  * @cpu: src CPU of the flush
138  */
139 void tlb_flush_all_cpus(CPUState *src_cpu);
140 /**
141  * tlb_flush_all_cpus_synced:
142  * @cpu: src CPU of the flush
143  *
144  * Like tlb_flush_all_cpus except this except the source vCPUs work is
145  * scheduled as safe work meaning all flushes will be complete once
146  * the source vCPUs safe work is complete. This will depend on when
147  * the guests translation ends the TB.
148  */
149 void tlb_flush_all_cpus_synced(CPUState *src_cpu);
150 /**
151  * tlb_flush_page_by_mmuidx:
152  * @cpu: CPU whose TLB should be flushed
153  * @addr: virtual address of page to be flushed
154  * @idxmap: bitmap of MMU indexes to flush
155  *
156  * Flush one page from the TLB of the specified CPU, for the specified
157  * MMU indexes.
158  */
159 void tlb_flush_page_by_mmuidx(CPUState *cpu, target_ulong addr,
160                               uint16_t idxmap);
161 /**
162  * tlb_flush_page_by_mmuidx_all_cpus:
163  * @cpu: Originating CPU of the flush
164  * @addr: virtual address of page to be flushed
165  * @idxmap: bitmap of MMU indexes to flush
166  *
167  * Flush one page from the TLB of all CPUs, for the specified
168  * MMU indexes.
169  */
170 void tlb_flush_page_by_mmuidx_all_cpus(CPUState *cpu, target_ulong addr,
171                                        uint16_t idxmap);
172 /**
173  * tlb_flush_page_by_mmuidx_all_cpus_synced:
174  * @cpu: Originating CPU of the flush
175  * @addr: virtual address of page to be flushed
176  * @idxmap: bitmap of MMU indexes to flush
177  *
178  * Flush one page from the TLB of all CPUs, for the specified MMU
179  * indexes like tlb_flush_page_by_mmuidx_all_cpus except the source
180  * vCPUs work is scheduled as safe work meaning all flushes will be
181  * complete once  the source vCPUs safe work is complete. This will
182  * depend on when the guests translation ends the TB.
183  */
184 void tlb_flush_page_by_mmuidx_all_cpus_synced(CPUState *cpu, target_ulong addr,
185                                               uint16_t idxmap);
186 /**
187  * tlb_flush_by_mmuidx:
188  * @cpu: CPU whose TLB should be flushed
189  * @wait: If true ensure synchronisation by exiting the cpu_loop
190  * @idxmap: bitmap of MMU indexes to flush
191  *
192  * Flush all entries from the TLB of the specified CPU, for the specified
193  * MMU indexes.
194  */
195 void tlb_flush_by_mmuidx(CPUState *cpu, uint16_t idxmap);
196 /**
197  * tlb_flush_by_mmuidx_all_cpus:
198  * @cpu: Originating CPU of the flush
199  * @idxmap: bitmap of MMU indexes to flush
200  *
201  * Flush all entries from all TLBs of all CPUs, for the specified
202  * MMU indexes.
203  */
204 void tlb_flush_by_mmuidx_all_cpus(CPUState *cpu, uint16_t idxmap);
205 /**
206  * tlb_flush_by_mmuidx_all_cpus_synced:
207  * @cpu: Originating CPU of the flush
208  * @idxmap: bitmap of MMU indexes to flush
209  *
210  * Flush all entries from all TLBs of all CPUs, for the specified
211  * MMU indexes like tlb_flush_by_mmuidx_all_cpus except except the source
212  * vCPUs work is scheduled as safe work meaning all flushes will be
213  * complete once  the source vCPUs safe work is complete. This will
214  * depend on when the guests translation ends the TB.
215  */
216 void tlb_flush_by_mmuidx_all_cpus_synced(CPUState *cpu, uint16_t idxmap);
217 
218 /**
219  * tlb_flush_page_bits_by_mmuidx
220  * @cpu: CPU whose TLB should be flushed
221  * @addr: virtual address of page to be flushed
222  * @idxmap: bitmap of mmu indexes to flush
223  * @bits: number of significant bits in address
224  *
225  * Similar to tlb_flush_page_mask, but with a bitmap of indexes.
226  */
227 void tlb_flush_page_bits_by_mmuidx(CPUState *cpu, target_ulong addr,
228                                    uint16_t idxmap, unsigned bits);
229 
230 /* Similarly, with broadcast and syncing. */
231 void tlb_flush_page_bits_by_mmuidx_all_cpus(CPUState *cpu, target_ulong addr,
232                                             uint16_t idxmap, unsigned bits);
233 void tlb_flush_page_bits_by_mmuidx_all_cpus_synced
234     (CPUState *cpu, target_ulong addr, uint16_t idxmap, unsigned bits);
235 
236 /**
237  * tlb_flush_range_by_mmuidx
238  * @cpu: CPU whose TLB should be flushed
239  * @addr: virtual address of the start of the range to be flushed
240  * @len: length of range to be flushed
241  * @idxmap: bitmap of mmu indexes to flush
242  * @bits: number of significant bits in address
243  *
244  * For each mmuidx in @idxmap, flush all pages within [@addr,@addr+@len),
245  * comparing only the low @bits worth of each virtual page.
246  */
247 void tlb_flush_range_by_mmuidx(CPUState *cpu, target_ulong addr,
248                                target_ulong len, uint16_t idxmap,
249                                unsigned bits);
250 
251 /* Similarly, with broadcast and syncing. */
252 void tlb_flush_range_by_mmuidx_all_cpus(CPUState *cpu, target_ulong addr,
253                                         target_ulong len, uint16_t idxmap,
254                                         unsigned bits);
255 void tlb_flush_range_by_mmuidx_all_cpus_synced(CPUState *cpu,
256                                                target_ulong addr,
257                                                target_ulong len,
258                                                uint16_t idxmap,
259                                                unsigned bits);
260 
261 /**
262  * tlb_set_page_with_attrs:
263  * @cpu: CPU to add this TLB entry for
264  * @vaddr: virtual address of page to add entry for
265  * @paddr: physical address of the page
266  * @attrs: memory transaction attributes
267  * @prot: access permissions (PAGE_READ/PAGE_WRITE/PAGE_EXEC bits)
268  * @mmu_idx: MMU index to insert TLB entry for
269  * @size: size of the page in bytes
270  *
271  * Add an entry to this CPU's TLB (a mapping from virtual address
272  * @vaddr to physical address @paddr) with the specified memory
273  * transaction attributes. This is generally called by the target CPU
274  * specific code after it has been called through the tlb_fill()
275  * entry point and performed a successful page table walk to find
276  * the physical address and attributes for the virtual address
277  * which provoked the TLB miss.
278  *
279  * At most one entry for a given virtual address is permitted. Only a
280  * single TARGET_PAGE_SIZE region is mapped; the supplied @size is only
281  * used by tlb_flush_page.
282  */
283 void tlb_set_page_with_attrs(CPUState *cpu, target_ulong vaddr,
284                              hwaddr paddr, MemTxAttrs attrs,
285                              int prot, int mmu_idx, target_ulong size);
286 /* tlb_set_page:
287  *
288  * This function is equivalent to calling tlb_set_page_with_attrs()
289  * with an @attrs argument of MEMTXATTRS_UNSPECIFIED. It's provided
290  * as a convenience for CPUs which don't use memory transaction attributes.
291  */
292 void tlb_set_page(CPUState *cpu, target_ulong vaddr,
293                   hwaddr paddr, int prot,
294                   int mmu_idx, target_ulong size);
295 #else
296 static inline void tlb_init(CPUState *cpu)
297 {
298 }
299 static inline void tlb_destroy(CPUState *cpu)
300 {
301 }
302 static inline void tlb_flush_page(CPUState *cpu, target_ulong addr)
303 {
304 }
305 static inline void tlb_flush_page_all_cpus(CPUState *src, target_ulong addr)
306 {
307 }
308 static inline void tlb_flush_page_all_cpus_synced(CPUState *src,
309                                                   target_ulong addr)
310 {
311 }
312 static inline void tlb_flush(CPUState *cpu)
313 {
314 }
315 static inline void tlb_flush_all_cpus(CPUState *src_cpu)
316 {
317 }
318 static inline void tlb_flush_all_cpus_synced(CPUState *src_cpu)
319 {
320 }
321 static inline void tlb_flush_page_by_mmuidx(CPUState *cpu,
322                                             target_ulong addr, uint16_t idxmap)
323 {
324 }
325 
326 static inline void tlb_flush_by_mmuidx(CPUState *cpu, uint16_t idxmap)
327 {
328 }
329 static inline void tlb_flush_page_by_mmuidx_all_cpus(CPUState *cpu,
330                                                      target_ulong addr,
331                                                      uint16_t idxmap)
332 {
333 }
334 static inline void tlb_flush_page_by_mmuidx_all_cpus_synced(CPUState *cpu,
335                                                             target_ulong addr,
336                                                             uint16_t idxmap)
337 {
338 }
339 static inline void tlb_flush_by_mmuidx_all_cpus(CPUState *cpu, uint16_t idxmap)
340 {
341 }
342 
343 static inline void tlb_flush_by_mmuidx_all_cpus_synced(CPUState *cpu,
344                                                        uint16_t idxmap)
345 {
346 }
347 static inline void tlb_flush_page_bits_by_mmuidx(CPUState *cpu,
348                                                  target_ulong addr,
349                                                  uint16_t idxmap,
350                                                  unsigned bits)
351 {
352 }
353 static inline void tlb_flush_page_bits_by_mmuidx_all_cpus(CPUState *cpu,
354                                                           target_ulong addr,
355                                                           uint16_t idxmap,
356                                                           unsigned bits)
357 {
358 }
359 static inline void
360 tlb_flush_page_bits_by_mmuidx_all_cpus_synced(CPUState *cpu, target_ulong addr,
361                                               uint16_t idxmap, unsigned bits)
362 {
363 }
364 static inline void tlb_flush_range_by_mmuidx(CPUState *cpu, target_ulong addr,
365                                              target_ulong len, uint16_t idxmap,
366                                              unsigned bits)
367 {
368 }
369 static inline void tlb_flush_range_by_mmuidx_all_cpus(CPUState *cpu,
370                                                       target_ulong addr,
371                                                       target_ulong len,
372                                                       uint16_t idxmap,
373                                                       unsigned bits)
374 {
375 }
376 static inline void tlb_flush_range_by_mmuidx_all_cpus_synced(CPUState *cpu,
377                                                              target_ulong addr,
378                                                              target_long len,
379                                                              uint16_t idxmap,
380                                                              unsigned bits)
381 {
382 }
383 #endif
384 /**
385  * probe_access:
386  * @env: CPUArchState
387  * @addr: guest virtual address to look up
388  * @size: size of the access
389  * @access_type: read, write or execute permission
390  * @mmu_idx: MMU index to use for lookup
391  * @retaddr: return address for unwinding
392  *
393  * Look up the guest virtual address @addr.  Raise an exception if the
394  * page does not satisfy @access_type.  Raise an exception if the
395  * access (@addr, @size) hits a watchpoint.  For writes, mark a clean
396  * page as dirty.
397  *
398  * Finally, return the host address for a page that is backed by RAM,
399  * or NULL if the page requires I/O.
400  */
401 void *probe_access(CPUArchState *env, target_ulong addr, int size,
402                    MMUAccessType access_type, int mmu_idx, uintptr_t retaddr);
403 
404 static inline void *probe_write(CPUArchState *env, target_ulong addr, int size,
405                                 int mmu_idx, uintptr_t retaddr)
406 {
407     return probe_access(env, addr, size, MMU_DATA_STORE, mmu_idx, retaddr);
408 }
409 
410 static inline void *probe_read(CPUArchState *env, target_ulong addr, int size,
411                                int mmu_idx, uintptr_t retaddr)
412 {
413     return probe_access(env, addr, size, MMU_DATA_LOAD, mmu_idx, retaddr);
414 }
415 
416 /**
417  * probe_access_flags:
418  * @env: CPUArchState
419  * @addr: guest virtual address to look up
420  * @access_type: read, write or execute permission
421  * @mmu_idx: MMU index to use for lookup
422  * @nonfault: suppress the fault
423  * @phost: return value for host address
424  * @retaddr: return address for unwinding
425  *
426  * Similar to probe_access, loosely returning the TLB_FLAGS_MASK for
427  * the page, and storing the host address for RAM in @phost.
428  *
429  * If @nonfault is set, do not raise an exception but return TLB_INVALID_MASK.
430  * Do not handle watchpoints, but include TLB_WATCHPOINT in the returned flags.
431  * Do handle clean pages, so exclude TLB_NOTDIRY from the returned flags.
432  * For simplicity, all "mmio-like" flags are folded to TLB_MMIO.
433  */
434 int probe_access_flags(CPUArchState *env, target_ulong addr,
435                        MMUAccessType access_type, int mmu_idx,
436                        bool nonfault, void **phost, uintptr_t retaddr);
437 
438 #define CODE_GEN_ALIGN           16 /* must be >= of the size of a icache line */
439 
440 /* Estimated block size for TB allocation.  */
441 /* ??? The following is based on a 2015 survey of x86_64 host output.
442    Better would seem to be some sort of dynamically sized TB array,
443    adapting to the block sizes actually being produced.  */
444 #if defined(CONFIG_SOFTMMU)
445 #define CODE_GEN_AVG_BLOCK_SIZE 400
446 #else
447 #define CODE_GEN_AVG_BLOCK_SIZE 150
448 #endif
449 
450 /*
451  * Translation Cache-related fields of a TB.
452  * This struct exists just for convenience; we keep track of TB's in a binary
453  * search tree, and the only fields needed to compare TB's in the tree are
454  * @ptr and @size.
455  * Note: the address of search data can be obtained by adding @size to @ptr.
456  */
457 struct tb_tc {
458     const void *ptr;    /* pointer to the translated code */
459     size_t size;
460 };
461 
462 struct TranslationBlock {
463     target_ulong pc;   /* simulated PC corresponding to this block (EIP + CS base) */
464     target_ulong cs_base; /* CS base for this block */
465     uint32_t flags; /* flags defining in which context the code was generated */
466     uint32_t cflags;    /* compile flags */
467 
468 /* Note that TCG_MAX_INSNS is 512; we validate this match elsewhere. */
469 #define CF_COUNT_MASK    0x000001ff
470 #define CF_NO_GOTO_TB    0x00000200 /* Do not chain with goto_tb */
471 #define CF_NO_GOTO_PTR   0x00000400 /* Do not chain with goto_ptr */
472 #define CF_SINGLE_STEP   0x00000800 /* gdbstub single-step in effect */
473 #define CF_LAST_IO       0x00008000 /* Last insn may be an IO access.  */
474 #define CF_MEMI_ONLY     0x00010000 /* Only instrument memory ops */
475 #define CF_USE_ICOUNT    0x00020000
476 #define CF_INVALID       0x00040000 /* TB is stale. Set with @jmp_lock held */
477 #define CF_PARALLEL      0x00080000 /* Generate code for a parallel context */
478 #define CF_NOIRQ         0x00100000 /* Generate an uninterruptible TB */
479 #define CF_CLUSTER_MASK  0xff000000 /* Top 8 bits are cluster ID */
480 #define CF_CLUSTER_SHIFT 24
481 
482     /* Per-vCPU dynamic tracing state used to generate this TB */
483     uint32_t trace_vcpu_dstate;
484 
485     /*
486      * Above fields used for comparing
487      */
488 
489     /* size of target code for this block (1 <= size <= TARGET_PAGE_SIZE) */
490     uint16_t size;
491     uint16_t icount;
492 
493     struct tb_tc tc;
494 
495     /* first and second physical page containing code. The lower bit
496        of the pointer tells the index in page_next[].
497        The list is protected by the TB's page('s) lock(s) */
498     uintptr_t page_next[2];
499     tb_page_addr_t page_addr[2];
500 
501     /* jmp_lock placed here to fill a 4-byte hole. Its documentation is below */
502     QemuSpin jmp_lock;
503 
504     /* The following data are used to directly call another TB from
505      * the code of this one. This can be done either by emitting direct or
506      * indirect native jump instructions. These jumps are reset so that the TB
507      * just continues its execution. The TB can be linked to another one by
508      * setting one of the jump targets (or patching the jump instruction). Only
509      * two of such jumps are supported.
510      */
511     uint16_t jmp_reset_offset[2]; /* offset of original jump target */
512 #define TB_JMP_RESET_OFFSET_INVALID 0xffff /* indicates no jump generated */
513     uintptr_t jmp_target_arg[2];  /* target address or offset */
514 
515     /*
516      * Each TB has a NULL-terminated list (jmp_list_head) of incoming jumps.
517      * Each TB can have two outgoing jumps, and therefore can participate
518      * in two lists. The list entries are kept in jmp_list_next[2]. The least
519      * significant bit (LSB) of the pointers in these lists is used to encode
520      * which of the two list entries is to be used in the pointed TB.
521      *
522      * List traversals are protected by jmp_lock. The destination TB of each
523      * outgoing jump is kept in jmp_dest[] so that the appropriate jmp_lock
524      * can be acquired from any origin TB.
525      *
526      * jmp_dest[] are tagged pointers as well. The LSB is set when the TB is
527      * being invalidated, so that no further outgoing jumps from it can be set.
528      *
529      * jmp_lock also protects the CF_INVALID cflag; a jump must not be chained
530      * to a destination TB that has CF_INVALID set.
531      */
532     uintptr_t jmp_list_head;
533     uintptr_t jmp_list_next[2];
534     uintptr_t jmp_dest[2];
535 };
536 
537 /* Hide the qatomic_read to make code a little easier on the eyes */
538 static inline uint32_t tb_cflags(const TranslationBlock *tb)
539 {
540     return qatomic_read(&tb->cflags);
541 }
542 
543 /* current cflags for hashing/comparison */
544 uint32_t curr_cflags(CPUState *cpu);
545 
546 /* TranslationBlock invalidate API */
547 #if defined(CONFIG_USER_ONLY)
548 void tb_invalidate_phys_addr(target_ulong addr);
549 void tb_invalidate_phys_range(target_ulong start, target_ulong end);
550 #else
551 void tb_invalidate_phys_addr(AddressSpace *as, hwaddr addr, MemTxAttrs attrs);
552 #endif
553 void tb_flush(CPUState *cpu);
554 void tb_phys_invalidate(TranslationBlock *tb, tb_page_addr_t page_addr);
555 TranslationBlock *tb_htable_lookup(CPUState *cpu, target_ulong pc,
556                                    target_ulong cs_base, uint32_t flags,
557                                    uint32_t cflags);
558 void tb_set_jmp_target(TranslationBlock *tb, int n, uintptr_t addr);
559 
560 /* GETPC is the true target of the return instruction that we'll execute.  */
561 #if defined(CONFIG_TCG_INTERPRETER)
562 extern __thread uintptr_t tci_tb_ptr;
563 # define GETPC() tci_tb_ptr
564 #else
565 # define GETPC() \
566     ((uintptr_t)__builtin_extract_return_addr(__builtin_return_address(0)))
567 #endif
568 
569 /* The true return address will often point to a host insn that is part of
570    the next translated guest insn.  Adjust the address backward to point to
571    the middle of the call insn.  Subtracting one would do the job except for
572    several compressed mode architectures (arm, mips) which set the low bit
573    to indicate the compressed mode; subtracting two works around that.  It
574    is also the case that there are no host isas that contain a call insn
575    smaller than 4 bytes, so we don't worry about special-casing this.  */
576 #define GETPC_ADJ   2
577 
578 #if !defined(CONFIG_USER_ONLY) && defined(CONFIG_DEBUG_TCG)
579 void assert_no_pages_locked(void);
580 #else
581 static inline void assert_no_pages_locked(void)
582 {
583 }
584 #endif
585 
586 #if !defined(CONFIG_USER_ONLY)
587 
588 /**
589  * iotlb_to_section:
590  * @cpu: CPU performing the access
591  * @index: TCG CPU IOTLB entry
592  *
593  * Given a TCG CPU IOTLB entry, return the MemoryRegionSection that
594  * it refers to. @index will have been initially created and returned
595  * by memory_region_section_get_iotlb().
596  */
597 struct MemoryRegionSection *iotlb_to_section(CPUState *cpu,
598                                              hwaddr index, MemTxAttrs attrs);
599 #endif
600 
601 #if defined(CONFIG_USER_ONLY)
602 void mmap_lock(void);
603 void mmap_unlock(void);
604 bool have_mmap_lock(void);
605 
606 /**
607  * get_page_addr_code() - user-mode version
608  * @env: CPUArchState
609  * @addr: guest virtual address of guest code
610  *
611  * Returns @addr.
612  */
613 static inline tb_page_addr_t get_page_addr_code(CPUArchState *env,
614                                                 target_ulong addr)
615 {
616     return addr;
617 }
618 
619 /**
620  * get_page_addr_code_hostp() - user-mode version
621  * @env: CPUArchState
622  * @addr: guest virtual address of guest code
623  *
624  * Returns @addr.
625  *
626  * If @hostp is non-NULL, sets *@hostp to the host address where @addr's content
627  * is kept.
628  */
629 static inline tb_page_addr_t get_page_addr_code_hostp(CPUArchState *env,
630                                                       target_ulong addr,
631                                                       void **hostp)
632 {
633     if (hostp) {
634         *hostp = g2h_untagged(addr);
635     }
636     return addr;
637 }
638 
639 /**
640  * adjust_signal_pc:
641  * @pc: raw pc from the host signal ucontext_t.
642  * @is_write: host memory operation was write, or read-modify-write.
643  *
644  * Alter @pc as required for unwinding.  Return the type of the
645  * guest memory access -- host reads may be for guest execution.
646  */
647 MMUAccessType adjust_signal_pc(uintptr_t *pc, bool is_write);
648 
649 /**
650  * handle_sigsegv_accerr_write:
651  * @cpu: the cpu context
652  * @old_set: the sigset_t from the signal ucontext_t
653  * @host_pc: the host pc, adjusted for the signal
654  * @host_addr: the host address of the fault
655  *
656  * Return true if the write fault has been handled, and should be re-tried.
657  */
658 bool handle_sigsegv_accerr_write(CPUState *cpu, sigset_t *old_set,
659                                  uintptr_t host_pc, abi_ptr guest_addr);
660 
661 /**
662  * cpu_loop_exit_sigsegv:
663  * @cpu: the cpu context
664  * @addr: the guest address of the fault
665  * @access_type: access was read/write/execute
666  * @maperr: true for invalid page, false for permission fault
667  * @ra: host pc for unwinding
668  *
669  * Use the TCGCPUOps hook to record cpu state, do guest operating system
670  * specific things to raise SIGSEGV, and jump to the main cpu loop.
671  */
672 void QEMU_NORETURN cpu_loop_exit_sigsegv(CPUState *cpu, target_ulong addr,
673                                          MMUAccessType access_type,
674                                          bool maperr, uintptr_t ra);
675 
676 /**
677  * cpu_loop_exit_sigbus:
678  * @cpu: the cpu context
679  * @addr: the guest address of the alignment fault
680  * @access_type: access was read/write/execute
681  * @ra: host pc for unwinding
682  *
683  * Use the TCGCPUOps hook to record cpu state, do guest operating system
684  * specific things to raise SIGBUS, and jump to the main cpu loop.
685  */
686 void QEMU_NORETURN cpu_loop_exit_sigbus(CPUState *cpu, target_ulong addr,
687                                         MMUAccessType access_type,
688                                         uintptr_t ra);
689 
690 #else
691 static inline void mmap_lock(void) {}
692 static inline void mmap_unlock(void) {}
693 
694 /**
695  * get_page_addr_code() - full-system version
696  * @env: CPUArchState
697  * @addr: guest virtual address of guest code
698  *
699  * If we cannot translate and execute from the entire RAM page, or if
700  * the region is not backed by RAM, returns -1. Otherwise, returns the
701  * ram_addr_t corresponding to the guest code at @addr.
702  *
703  * Note: this function can trigger an exception.
704  */
705 tb_page_addr_t get_page_addr_code(CPUArchState *env, target_ulong addr);
706 
707 /**
708  * get_page_addr_code_hostp() - full-system version
709  * @env: CPUArchState
710  * @addr: guest virtual address of guest code
711  *
712  * See get_page_addr_code() (full-system version) for documentation on the
713  * return value.
714  *
715  * Sets *@hostp (when @hostp is non-NULL) as follows.
716  * If the return value is -1, sets *@hostp to NULL. Otherwise, sets *@hostp
717  * to the host address where @addr's content is kept.
718  *
719  * Note: this function can trigger an exception.
720  */
721 tb_page_addr_t get_page_addr_code_hostp(CPUArchState *env, target_ulong addr,
722                                         void **hostp);
723 
724 void tlb_reset_dirty(CPUState *cpu, ram_addr_t start1, ram_addr_t length);
725 void tlb_set_dirty(CPUState *cpu, target_ulong vaddr);
726 
727 MemoryRegionSection *
728 address_space_translate_for_iotlb(CPUState *cpu, int asidx, hwaddr addr,
729                                   hwaddr *xlat, hwaddr *plen,
730                                   MemTxAttrs attrs, int *prot);
731 hwaddr memory_region_section_get_iotlb(CPUState *cpu,
732                                        MemoryRegionSection *section);
733 #endif
734 
735 #endif
736