diff options
| -rw-r--r-- | sys/include/sys/mutex.h | 52 | ||||
| -rw-r--r-- | sys/kern/kern_synch.c | 57 |
2 files changed, 109 insertions, 0 deletions
diff --git a/sys/include/sys/mutex.h b/sys/include/sys/mutex.h new file mode 100644 index 0000000..8a4d50a --- /dev/null +++ b/sys/include/sys/mutex.h @@ -0,0 +1,52 @@ +/* + * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of Hyra nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#ifndef _SYS_MUTEX_H_ +#define _SYS_MUTEX_H_ + +#include <sys/types.h> +#include <vm/dynalloc.h> + +#define MUTEX_NAME_LEN 32 + +#if defined(_KERNEL) + +struct mutex { + char name[MUTEX_NAME_LEN]; + volatile uint8_t lock; +}; + +struct mutex *mutex_new(const char *name); +void mutex_free(struct mutex *mtx); + +int mutex_acquire(struct mutex *mtx, int flags); +void mutex_release(struct mutex *mtx); + +#endif /* _KERNEL */ +#endif /* !_SYS_MUTEX_H_ */ diff --git a/sys/kern/kern_synch.c b/sys/kern/kern_synch.c index 57b27d0..0d36d7f 100644 --- a/sys/kern/kern_synch.c +++ b/sys/kern/kern_synch.c @@ -28,12 +28,15 @@ */ #include <sys/types.h> +#include <sys/mutex.h> #include <sys/systm.h> #include <sys/errno.h> +#include <sys/sched.h> #include <sys/atomic.h> #include <sys/syslog.h> #include <sys/spinlock.h> #include <dev/timer.h> +#include <string.h> #define pr_trace(fmt, ...) kprintf("synch: " fmt, ##__VA_ARGS__) #define pr_error(...) pr_trace(__VA_ARGS__) @@ -136,3 +139,57 @@ sysrel(void) { spinlock_release(&__syslock); } + +/* + * Create a new mutex lock object + */ +struct mutex * +mutex_new(const char *name) +{ + struct mutex *mtx; + size_t namelen; + + mtx = dynalloc(sizeof(*mtx)); + if (mtx == NULL) { + return NULL; + } + + mtx->lock = 0; + namelen = strlen(name); + + /* Don't overflow the name buffer */ + if (namelen >= MUTEX_NAME_LEN) { + namelen = MUTEX_NAME_LEN - 1; + } + + memcpy(mtx->name, name, namelen); + return mtx; +} + +/* + * Acquire a mutex + * + * @mtx: Mutex to acquire + * @flags: Optional flags + */ +int +mutex_acquire(struct mutex *mtx, int flags) +{ + while (__atomic_test_and_set(&mtx->lock, __ATOMIC_ACQUIRE)) { + sched_yield(); + } + + return 0; +} + +void +mutex_release(struct mutex *mtx) +{ + __atomic_clear(&mtx->lock, __ATOMIC_RELEASE); +} + +void +mutex_free(struct mutex *mtx) +{ + dynfree(mtx); +} |