From b42358eaa274b037a13fcb60e52559f1244f34fc Mon Sep 17 00:00:00 2001 From: Ralph Metzler Date: Mon, 11 Dec 2017 16:10:37 +0100 Subject: [PATCH] backwards compatibility --- dvb-core/dvb_net.c | 5 +++- dvb-core/dvb_ringbuffer.c | 49 ++++++++++++++++++++++++++++++++++++++- 2 files changed, 52 insertions(+), 2 deletions(-) diff --git a/dvb-core/dvb_net.c b/dvb-core/dvb_net.c index d6886d5..e22fbef 100644 --- a/dvb-core/dvb_net.c +++ b/dvb-core/dvb_net.c @@ -1382,7 +1382,10 @@ static int dvb_net_add_if(struct dvb_net *dvbnet, u16 pid, u8 feedtype) return -EINVAL; net = alloc_netdev(sizeof(struct dvb_net_priv), "dvb", - NET_NAME_UNKNOWN, dvb_net_setup); +#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3, 14, 0)) + NET_NAME_UNKNOWN, +#endif + dvb_net_setup); if (!net) return -ENOMEM; diff --git a/dvb-core/dvb_ringbuffer.c b/dvb-core/dvb_ringbuffer.c index 46eac0a..223fcce 100644 --- a/dvb-core/dvb_ringbuffer.c +++ b/dvb-core/dvb_ringbuffer.c @@ -56,6 +56,9 @@ void dvb_ringbuffer_init(struct dvb_ringbuffer *rbuf, void *data, size_t len) int dvb_ringbuffer_empty(struct dvb_ringbuffer *rbuf) { +#if (LINUX_VERSION_CODE < KERNEL_VERSION(3, 14, 0)) + return (rbuf->pread == rbuf->pwrite); +#else /* smp_load_acquire() to load write pointer on reader side * this pairs with smp_store_release() in dvb_ringbuffer_write(), * dvb_ringbuffer_write_user(), or dvb_ringbuffer_reset() @@ -63,6 +66,7 @@ int dvb_ringbuffer_empty(struct dvb_ringbuffer *rbuf) * for memory barriers also see Documentation/circular-buffers.txt */ return (rbuf->pread == smp_load_acquire(&rbuf->pwrite)); +#endif } @@ -88,11 +92,15 @@ ssize_t dvb_ringbuffer_avail(struct dvb_ringbuffer *rbuf) { ssize_t avail; +#if (LINUX_VERSION_CODE < KERNEL_VERSION(3, 14, 0)) + avail = rbuf->pwrite - rbuf->pread; +#else /* smp_load_acquire() to load write pointer on reader side * this pairs with smp_store_release() in dvb_ringbuffer_write(), * dvb_ringbuffer_write_user(), or dvb_ringbuffer_reset() */ avail = smp_load_acquire(&rbuf->pwrite) - rbuf->pread; +#endif if (avail < 0) avail += rbuf->size; return avail; @@ -102,6 +110,9 @@ ssize_t dvb_ringbuffer_avail(struct dvb_ringbuffer *rbuf) void dvb_ringbuffer_flush(struct dvb_ringbuffer *rbuf) { +#if (LINUX_VERSION_CODE < KERNEL_VERSION(3, 14, 0)) + rbuf->pread = smp_load_acquire(&rbuf->pwrite; +#else /* dvb_ringbuffer_flush() counts as read operation * smp_load_acquire() to load write pointer * smp_store_release() to update read pointer, this ensures that the @@ -109,18 +120,23 @@ void dvb_ringbuffer_flush(struct dvb_ringbuffer *rbuf) * calls on other cpu cores */ smp_store_release(&rbuf->pread, smp_load_acquire(&rbuf->pwrite)); +#endif rbuf->error = 0; } EXPORT_SYMBOL(dvb_ringbuffer_flush); void dvb_ringbuffer_reset(struct dvb_ringbuffer *rbuf) { +#if (LINUX_VERSION_CODE < KERNEL_VERSION(3, 14, 0)) + rbuf->pread = rbuf->pwrite = 0; +#else /* dvb_ringbuffer_reset() counts as read and write operation * smp_store_release() to update read pointer */ smp_store_release(&rbuf->pread, 0); /* smp_store_release() to update write pointer */ smp_store_release(&rbuf->pwrite, 0); +#endif rbuf->error = 0; } @@ -146,18 +162,25 @@ ssize_t dvb_ringbuffer_read_user(struct dvb_ringbuffer *rbuf, u8 __user *buf, si return -EFAULT; buf += split; todo -= split; +#if (LINUX_VERSION_CODE < KERNEL_VERSION(3, 14, 0)) + rbuf->pread = 0; +#else /* smp_store_release() for read pointer update to ensure * that buf is not overwritten until read is complete, * this pairs with ACCESS_ONCE() in dvb_ringbuffer_free() */ smp_store_release(&rbuf->pread, 0); +#endif } if (copy_to_user(buf, rbuf->data+rbuf->pread, todo)) return -EFAULT; +#if (LINUX_VERSION_CODE < KERNEL_VERSION(3, 14, 0)) + rbuf->pread = (rbuf->pread + todo) % rbuf->size; +#else /* smp_store_release() to update read pointer, see above */ smp_store_release(&rbuf->pread, (rbuf->pread + todo) % rbuf->size); - +#endif return len; } @@ -171,16 +194,24 @@ void dvb_ringbuffer_read(struct dvb_ringbuffer *rbuf, u8 *buf, size_t len) memcpy(buf, rbuf->data+rbuf->pread, split); buf += split; todo -= split; +#if (LINUX_VERSION_CODE < KERNEL_VERSION(3, 14, 0)) + rbuf->pread = 0; +#else /* smp_store_release() for read pointer update to ensure * that buf is not overwritten until read is complete, * this pairs with ACCESS_ONCE() in dvb_ringbuffer_free() */ smp_store_release(&rbuf->pread, 0); +#endif } memcpy(buf, rbuf->data+rbuf->pread, todo); +#if (LINUX_VERSION_CODE < KERNEL_VERSION(3, 14, 0)) + rbuf->pread = (rbuf->pread + todo) % rbuf->size; +#else /* smp_store_release() to update read pointer, see above */ smp_store_release(&rbuf->pread, (rbuf->pread + todo) % rbuf->size); +#endif } @@ -195,16 +226,24 @@ ssize_t dvb_ringbuffer_write(struct dvb_ringbuffer *rbuf, const u8 *buf, size_t memcpy(rbuf->data+rbuf->pwrite, buf, split); buf += split; todo -= split; +#if (LINUX_VERSION_CODE < KERNEL_VERSION(3, 14, 0)) + rbuf->pwrite = 0; +#else /* smp_store_release() for write pointer update to ensure that * written data is visible on other cpu cores before the pointer * update, this pairs with smp_load_acquire() in * dvb_ringbuffer_empty() or dvb_ringbuffer_avail() */ smp_store_release(&rbuf->pwrite, 0); +#endif } memcpy(rbuf->data+rbuf->pwrite, buf, todo); +#if (LINUX_VERSION_CODE < KERNEL_VERSION(3, 14, 0)) + rbuf->pwrite = (rbuf->pwrite + todo) % rbuf->size; +#else /* smp_store_release() for write pointer update, see above */ smp_store_release(&rbuf->pwrite, (rbuf->pwrite + todo) % rbuf->size); +#endif return len; } @@ -224,18 +263,26 @@ ssize_t dvb_ringbuffer_write_user(struct dvb_ringbuffer *rbuf, return len - todo; buf += split; todo -= split; +#if (LINUX_VERSION_CODE < KERNEL_VERSION(3, 14, 0)) + rbuf->pwrite = 0; +#else /* smp_store_release() for write pointer update to ensure that * written data is visible on other cpu cores before the pointer * update, this pairs with smp_load_acquire() in * dvb_ringbuffer_empty() or dvb_ringbuffer_avail() */ smp_store_release(&rbuf->pwrite, 0); +#endif } status = copy_from_user(rbuf->data+rbuf->pwrite, buf, todo); if (status) return len - todo; +#if (LINUX_VERSION_CODE < KERNEL_VERSION(3, 14, 0)) + rbuf->pwrite = (rbuf->pwrite + todo) % rbuf->size; +#else /* smp_store_release() for write pointer update, see above */ smp_store_release(&rbuf->pwrite, (rbuf->pwrite + todo) % rbuf->size); +#endif return len; }