| 1 | /* |
| 2 | * Accelerator blocking API, to prevent new ioctls from starting and wait the |
| 3 | * running ones finish. |
| 4 | * This mechanism differs from pause/resume_all_vcpus() in that it does not |
| 5 | * release the BQL. |
| 6 | * |
| 7 | * Copyright (c) 2022 Red Hat Inc. |
| 8 | * |
| 9 | * Author: Emanuele Giuseppe Esposito <eesposit@redhat.com> |
| 10 | * |
| 11 | * This work is licensed under the terms of the GNU GPL, version 2 or later. |
| 12 | * See the COPYING file in the top-level directory. |
| 13 | */ |
| 14 | #ifndef ACCEL_BLOCKER_H |
| 15 | #define ACCEL_BLOCKER_H |
| 16 | |
| 17 | #include "system/cpus.h" |
| 18 | |
| 19 | void accel_blocker_init(void); |
| 20 | |
| 21 | /* |
| 22 | * accel_{cpu_}ioctl_begin/end: |
| 23 | * Mark when ioctl is about to run or just finished. |
| 24 | * |
| 25 | * accel_{cpu_}ioctl_begin will block after accel_ioctl_inhibit_begin() is |
| 26 | * called, preventing new ioctls to run. They will continue only after |
| 27 | * accel_ioctl_inibith_end(). |
| 28 | */ |
| 29 | void accel_ioctl_begin(void); |
| 30 | void accel_ioctl_end(void); |
| 31 | void accel_cpu_ioctl_begin(CPUState *cpu); |
| 32 | void accel_cpu_ioctl_end(CPUState *cpu); |
| 33 | |
| 34 | /* |
| 35 | * accel_ioctl_inhibit_begin: start critical section |
| 36 | * |
| 37 | * This function makes sure that: |
| 38 | * 1) incoming accel_{cpu_}ioctl_begin() calls block |
| 39 | * 2) wait that all ioctls that were already running reach |
| 40 | * accel_{cpu_}ioctl_end(), kicking vcpus if necessary. |
| 41 | * |
| 42 | * This allows the caller to access shared data or perform operations without |
| 43 | * worrying of concurrent vcpus accesses. |
| 44 | */ |
| 45 | void accel_ioctl_inhibit_begin(void); |
| 46 | |
| 47 | /* |
| 48 | * accel_ioctl_inhibit_end: end critical section started by |
| 49 | * accel_ioctl_inhibit_begin() |
| 50 | * |
| 51 | * This function allows blocked accel_{cpu_}ioctl_begin() to continue. |
| 52 | */ |
| 53 | void accel_ioctl_inhibit_end(void); |
| 54 | |
| 55 | #endif /* ACCEL_BLOCKER_H */ |