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Diffstat (limited to 'backport-include/linux/kfifo.h')
| -rw-r--r-- | backport-include/linux/kfifo.h | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/backport-include/linux/kfifo.h b/backport-include/linux/kfifo.h new file mode 100644 index 0000000..b4fda3c --- /dev/null +++ b/backport-include/linux/kfifo.h @@ -0,0 +1,51 @@ +#ifndef BACKPORT_LINUX_KFIFO_H +#define BACKPORT_LINUX_KFIFO_H + +#include <linux/version.h> +#include_next <linux/kfifo.h> + +#if LINUX_VERSION_IS_LESS(3,13,0) +#undef kfifo_put +/** + * kfifo_put - put data into the fifo + * @fifo: address of the fifo to be used + * @val: the data to be added + * + * This macro copies the given value into the fifo. + * It returns 0 if the fifo was full. Otherwise it returns the number + * processed elements. + * + * Note that with only one concurrent reader and one concurrent + * writer, you don't need extra locking to use these macro. + */ +#define kfifo_put(fifo, val) \ +({ \ + typeof((fifo) + 1) __tmp = (fifo); \ + typeof((&val) + 1) __val = (&val); \ + unsigned int __ret; \ + const size_t __recsize = sizeof(*__tmp->rectype); \ + struct __kfifo *__kfifo = &__tmp->kfifo; \ + if (0) { \ + typeof(__tmp->ptr_const) __dummy __attribute__ ((unused)); \ + __dummy = (typeof(__val))NULL; \ + } \ + if (__recsize) \ + __ret = __kfifo_in_r(__kfifo, __val, sizeof(*__val), \ + __recsize); \ + else { \ + __ret = !kfifo_is_full(__tmp); \ + if (__ret) { \ + (__is_kfifo_ptr(__tmp) ? \ + ((typeof(__tmp->type))__kfifo->data) : \ + (__tmp->buf) \ + )[__kfifo->in & __tmp->kfifo.mask] = \ + *(typeof(__tmp->type))__val; \ + smp_wmb(); \ + __kfifo->in++; \ + } \ + } \ + __ret; \ +}) +#endif + +#endif /* BACKPORT_LINUX_KFIFO_H */ |