xref: /qemu/include/accel/tcg/cpu-ops.h (revision bcfee4938f8d4e8bf5f49981d3c8a78cf267cb4e)
1 /*
2  * TCG CPU-specific operations
3  *
4  * Copyright 2021 SUSE LLC
5  *
6  * This work is licensed under the terms of the GNU GPL, version 2 or later.
7  * See the COPYING file in the top-level directory.
8  */
9 
10 #ifndef TCG_CPU_OPS_H
11 #define TCG_CPU_OPS_H
12 
13 #include "exec/breakpoint.h"
14 #include "exec/hwaddr.h"
15 #include "exec/memattrs.h"
16 #include "exec/memop.h"
17 #include "exec/mmu-access-type.h"
18 #include "exec/vaddr.h"
19 #include "tcg/tcg-mo.h"
20 
21 struct TCGCPUOps {
22     /**
23      * mttcg_supported: multi-threaded TCG is supported
24      *
25      * Target (TCG frontend) supports:
26      *   - atomic instructions
27      *   - memory ordering primitives (barriers)
28      */
29     bool mttcg_supported;
30 
31     /**
32      * @guest_default_memory_order: default barrier that is required
33      *                              for the guest memory ordering.
34      */
35     TCGBar guest_default_memory_order;
36 
37     /**
38      * @initialize: Initialize TCG state
39      *
40      * Called when the first CPU is realized.
41      */
42     void (*initialize)(void);
43     /**
44      * @translate_code: Translate guest instructions to TCGOps
45      * @cpu: cpu context
46      * @tb: translation block
47      * @max_insns: max number of instructions to translate
48      * @pc: guest virtual program counter address
49      * @host_pc: host physical program counter address
50      *
51      * This function must be provided by the target, which should create
52      * the target-specific DisasContext, and then invoke translator_loop.
53      */
54     void (*translate_code)(CPUState *cpu, TranslationBlock *tb,
55                            int *max_insns, vaddr pc, void *host_pc);
56     /**
57      * @synchronize_from_tb: Synchronize state from a TCG #TranslationBlock
58      *
59      * This is called when we abandon execution of a TB before starting it,
60      * and must set all parts of the CPU state which the previous TB in the
61      * chain may not have updated.
62      * By default, when this is NULL, a call is made to @set_pc(tb->pc).
63      *
64      * If more state needs to be restored, the target must implement a
65      * function to restore all the state, and register it here.
66      */
67     void (*synchronize_from_tb)(CPUState *cpu, const TranslationBlock *tb);
68     /**
69      * @restore_state_to_opc: Synchronize state from INDEX_op_start_insn
70      *
71      * This is called when we unwind state in the middle of a TB,
72      * usually before raising an exception.  Set all part of the CPU
73      * state which are tracked insn-by-insn in the target-specific
74      * arguments to start_insn, passed as @data.
75      */
76     void (*restore_state_to_opc)(CPUState *cpu, const TranslationBlock *tb,
77                                  const uint64_t *data);
78 
79     /** @cpu_exec_enter: Callback for cpu_exec preparation */
80     void (*cpu_exec_enter)(CPUState *cpu);
81     /** @cpu_exec_exit: Callback for cpu_exec cleanup */
82     void (*cpu_exec_exit)(CPUState *cpu);
83     /** @debug_excp_handler: Callback for handling debug exceptions */
84     void (*debug_excp_handler)(CPUState *cpu);
85 
86     /** @mmu_index: Callback for choosing softmmu mmu index */
87     int (*mmu_index)(CPUState *cpu, bool ifetch);
88 
89 #ifdef CONFIG_USER_ONLY
90     /**
91      * @fake_user_interrupt: Callback for 'fake exception' handling.
92      *
93      * Simulate 'fake exception' which will be handled outside the
94      * cpu execution loop (hack for x86 user mode).
95      */
96     void (*fake_user_interrupt)(CPUState *cpu);
97 
98     /**
99      * record_sigsegv:
100      * @cpu: cpu context
101      * @addr: faulting guest address
102      * @access_type: access was read/write/execute
103      * @maperr: true for invalid page, false for permission fault
104      * @ra: host pc for unwinding
105      *
106      * We are about to raise SIGSEGV with si_code set for @maperr,
107      * and si_addr set for @addr.  Record anything further needed
108      * for the signal ucontext_t.
109      *
110      * If the emulated kernel does not provide anything to the signal
111      * handler with anything besides the user context registers, and
112      * the siginfo_t, then this hook need do nothing and may be omitted.
113      * Otherwise, record the data and return; the caller will raise
114      * the signal, unwind the cpu state, and return to the main loop.
115      *
116      * If it is simpler to re-use the sysemu tlb_fill code, @ra is provided
117      * so that a "normal" cpu exception can be raised.  In this case,
118      * the signal must be raised by the architecture cpu_loop.
119      */
120     void (*record_sigsegv)(CPUState *cpu, vaddr addr,
121                            MMUAccessType access_type,
122                            bool maperr, uintptr_t ra);
123     /**
124      * record_sigbus:
125      * @cpu: cpu context
126      * @addr: misaligned guest address
127      * @access_type: access was read/write/execute
128      * @ra: host pc for unwinding
129      *
130      * We are about to raise SIGBUS with si_code BUS_ADRALN,
131      * and si_addr set for @addr.  Record anything further needed
132      * for the signal ucontext_t.
133      *
134      * If the emulated kernel does not provide the signal handler with
135      * anything besides the user context registers, and the siginfo_t,
136      * then this hook need do nothing and may be omitted.
137      * Otherwise, record the data and return; the caller will raise
138      * the signal, unwind the cpu state, and return to the main loop.
139      *
140      * If it is simpler to re-use the sysemu do_unaligned_access code,
141      * @ra is provided so that a "normal" cpu exception can be raised.
142      * In this case, the signal must be raised by the architecture cpu_loop.
143      */
144     void (*record_sigbus)(CPUState *cpu, vaddr addr,
145                           MMUAccessType access_type, uintptr_t ra);
146 #else
147     /** @do_interrupt: Callback for interrupt handling.  */
148     void (*do_interrupt)(CPUState *cpu);
149     /** @cpu_exec_interrupt: Callback for processing interrupts in cpu_exec */
150     bool (*cpu_exec_interrupt)(CPUState *cpu, int interrupt_request);
151     /**
152      * @cpu_exec_halt: Callback for handling halt in cpu_exec.
153      *
154      * The target CPU should do any special processing here that it needs
155      * to do when the CPU is in the halted state.
156      *
157      * Return true to indicate that the CPU should now leave halt, false
158      * if it should remain in the halted state. (This should generally
159      * be the same value that cpu_has_work() would return.)
160      *
161      * This method must be provided. If the target does not need to
162      * do anything special for halt, the same function used for its
163      * SysemuCPUOps::has_work method can be used here, as they have the
164      * same function signature.
165      */
166     bool (*cpu_exec_halt)(CPUState *cpu);
167     /**
168      * @tlb_fill_align: Handle a softmmu tlb miss
169      * @cpu: cpu context
170      * @out: output page properties
171      * @addr: virtual address
172      * @access_type: read, write or execute
173      * @mmu_idx: mmu context
174      * @memop: memory operation for the access
175      * @size: memory access size, or 0 for whole page
176      * @probe: test only, no fault
177      * @ra: host return address for exception unwind
178      *
179      * If the access is valid, fill in @out and return true.
180      * Otherwise if probe is true, return false.
181      * Otherwise raise an exception and do not return.
182      *
183      * The alignment check for the access is deferred to this hook,
184      * so that the target can determine the priority of any alignment
185      * fault with respect to other potential faults from paging.
186      * Zero may be passed for @memop to skip any alignment check
187      * for non-memory-access operations such as probing.
188      */
189     bool (*tlb_fill_align)(CPUState *cpu, CPUTLBEntryFull *out, vaddr addr,
190                            MMUAccessType access_type, int mmu_idx,
191                            MemOp memop, int size, bool probe, uintptr_t ra);
192     /**
193      * @tlb_fill: Handle a softmmu tlb miss
194      *
195      * If the access is valid, call tlb_set_page and return true;
196      * if the access is invalid and probe is true, return false;
197      * otherwise raise an exception and do not return.
198      */
199     bool (*tlb_fill)(CPUState *cpu, vaddr address, int size,
200                      MMUAccessType access_type, int mmu_idx,
201                      bool probe, uintptr_t retaddr);
202     /**
203      * @do_transaction_failed: Callback for handling failed memory transactions
204      * (ie bus faults or external aborts; not MMU faults)
205      */
206     void (*do_transaction_failed)(CPUState *cpu, hwaddr physaddr, vaddr addr,
207                                   unsigned size, MMUAccessType access_type,
208                                   int mmu_idx, MemTxAttrs attrs,
209                                   MemTxResult response, uintptr_t retaddr);
210     /**
211      * @do_unaligned_access: Callback for unaligned access handling
212      * The callback must exit via raising an exception.
213      */
214     G_NORETURN void (*do_unaligned_access)(CPUState *cpu, vaddr addr,
215                                            MMUAccessType access_type,
216                                            int mmu_idx, uintptr_t retaddr);
217 
218     /**
219      * @adjust_watchpoint_address: hack for cpu_check_watchpoint used by ARM
220      */
221     vaddr (*adjust_watchpoint_address)(CPUState *cpu, vaddr addr, int len);
222 
223     /**
224      * @debug_check_watchpoint: return true if the architectural
225      * watchpoint whose address has matched should really fire, used by ARM
226      * and RISC-V
227      */
228     bool (*debug_check_watchpoint)(CPUState *cpu, CPUWatchpoint *wp);
229 
230     /**
231      * @debug_check_breakpoint: return true if the architectural
232      * breakpoint whose PC has matched should really fire.
233      */
234     bool (*debug_check_breakpoint)(CPUState *cpu);
235 
236     /**
237      * @io_recompile_replay_branch: Callback for cpu_io_recompile.
238      *
239      * The cpu has been stopped, and cpu_restore_state_from_tb has been
240      * called.  If the faulting instruction is in a delay slot, and the
241      * target architecture requires re-execution of the branch, then
242      * adjust the cpu state as required and return true.
243      */
244     bool (*io_recompile_replay_branch)(CPUState *cpu,
245                                        const TranslationBlock *tb);
246     /**
247      * @need_replay_interrupt: Return %true if @interrupt_request
248      * needs to be recorded for replay purposes.
249      */
250     bool (*need_replay_interrupt)(int interrupt_request);
251 #endif /* !CONFIG_USER_ONLY */
252 };
253 
254 #if defined(CONFIG_USER_ONLY)
255 
256 static inline void cpu_check_watchpoint(CPUState *cpu, vaddr addr, vaddr len,
257                                         MemTxAttrs atr, int fl, uintptr_t ra)
258 {
259 }
260 
261 static inline int cpu_watchpoint_address_matches(CPUState *cpu,
262                                                  vaddr addr, vaddr len)
263 {
264     return 0;
265 }
266 
267 #else
268 
269 /**
270  * cpu_check_watchpoint:
271  * @cpu: cpu context
272  * @addr: guest virtual address
273  * @len: access length
274  * @attrs: memory access attributes
275  * @flags: watchpoint access type
276  * @ra: unwind return address
277  *
278  * Check for a watchpoint hit in [addr, addr+len) of the type
279  * specified by @flags.  Exit via exception with a hit.
280  */
281 void cpu_check_watchpoint(CPUState *cpu, vaddr addr, vaddr len,
282                           MemTxAttrs attrs, int flags, uintptr_t ra);
283 
284 /**
285  * cpu_watchpoint_address_matches:
286  * @cpu: cpu context
287  * @addr: guest virtual address
288  * @len: access length
289  *
290  * Return the watchpoint flags that apply to [addr, addr+len).
291  * If no watchpoint is registered for the range, the result is 0.
292  */
293 int cpu_watchpoint_address_matches(CPUState *cpu, vaddr addr, vaddr len);
294 
295 #endif
296 
297 #endif /* TCG_CPU_OPS_H */
298