diff options
Diffstat (limited to 'drivers/hv/channel.c')
| -rw-r--r-- | drivers/hv/channel.c | 99 |
1 files changed, 10 insertions, 89 deletions
diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c index 5e482d7..8a8148f 100644 --- a/drivers/hv/channel.c +++ b/drivers/hv/channel.c @@ -39,7 +39,7 @@ * vmbus_setevent- Trigger an event notification on the specified * channel. */ -static void vmbus_setevent(struct vmbus_channel *channel) +void vmbus_setevent(struct vmbus_channel *channel) { struct hv_monitor_page *monitorpage; @@ -65,6 +65,7 @@ static void vmbus_setevent(struct vmbus_channel *channel) vmbus_set_event(channel); } } +EXPORT_SYMBOL_GPL(vmbus_setevent); /* * vmbus_open - Open the specified channel. @@ -635,8 +636,6 @@ int vmbus_sendpacket_ctl(struct vmbus_channel *channel, void *buffer, u32 packetlen_aligned = ALIGN(packetlen, sizeof(u64)); struct kvec bufferlist[3]; u64 aligned_data = 0; - int ret; - bool signal = false; bool lock = channel->acquire_ring_lock; int num_vecs = ((bufferlen != 0) ? 3 : 1); @@ -656,41 +655,9 @@ int vmbus_sendpacket_ctl(struct vmbus_channel *channel, void *buffer, bufferlist[2].iov_base = &aligned_data; bufferlist[2].iov_len = (packetlen_aligned - packetlen); - ret = hv_ringbuffer_write(&channel->outbound, bufferlist, num_vecs, - &signal, lock, channel->signal_policy); - - /* - * Signalling the host is conditional on many factors: - * 1. The ring state changed from being empty to non-empty. - * This is tracked by the variable "signal". - * 2. The variable kick_q tracks if more data will be placed - * on the ring. We will not signal if more data is - * to be placed. - * - * Based on the channel signal state, we will decide - * which signaling policy will be applied. - * - * If we cannot write to the ring-buffer; signal the host - * even if we may not have written anything. This is a rare - * enough condition that it should not matter. - * NOTE: in this case, the hvsock channel is an exception, because - * it looks the host side's hvsock implementation has a throttling - * mechanism which can hurt the performance otherwise. - * - * KYS: Oct. 30, 2016: - * It looks like Windows hosts have logic to deal with DOS attacks that - * can be triggered if it receives interrupts when it is not expecting - * the interrupt. The host expects interrupts only when the ring - * transitions from empty to non-empty (or full to non full on the guest - * to host ring). - * So, base the signaling decision solely on the ring state until the - * host logic is fixed. - */ - - if (((ret == 0) && signal)) - vmbus_setevent(channel); + return hv_ringbuffer_write(channel, bufferlist, num_vecs, + lock, kick_q); - return ret; } EXPORT_SYMBOL(vmbus_sendpacket_ctl); @@ -731,7 +698,6 @@ int vmbus_sendpacket_pagebuffer_ctl(struct vmbus_channel *channel, u32 flags, bool kick_q) { - int ret; int i; struct vmbus_channel_packet_page_buffer desc; u32 descsize; @@ -739,7 +705,6 @@ int vmbus_sendpacket_pagebuffer_ctl(struct vmbus_channel *channel, u32 packetlen_aligned; struct kvec bufferlist[3]; u64 aligned_data = 0; - bool signal = false; bool lock = channel->acquire_ring_lock; if (pagecount > MAX_PAGE_BUFFER_COUNT) @@ -777,38 +742,8 @@ int vmbus_sendpacket_pagebuffer_ctl(struct vmbus_channel *channel, bufferlist[2].iov_base = &aligned_data; bufferlist[2].iov_len = (packetlen_aligned - packetlen); - ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, - &signal, lock, channel->signal_policy); - - /* - * Signalling the host is conditional on many factors: - * 1. The ring state changed from being empty to non-empty. - * This is tracked by the variable "signal". - * 2. The variable kick_q tracks if more data will be placed - * on the ring. We will not signal if more data is - * to be placed. - * - * Based on the channel signal state, we will decide - * which signaling policy will be applied. - * - * If we cannot write to the ring-buffer; signal the host - * even if we may not have written anything. This is a rare - * enough condition that it should not matter. - * - * KYS: Oct. 30, 2016: - * It looks like Windows hosts have logic to deal with DOS attacks that - * can be triggered if it receives interrupts when it is not expecting - * the interrupt. The host expects interrupts only when the ring - * transitions from empty to non-empty (or full to non full on the guest - * to host ring). - * So, base the signaling decision solely on the ring state until the - * host logic is fixed. - */ - - if (((ret == 0) && signal)) - vmbus_setevent(channel); - - return ret; + return hv_ringbuffer_write(channel, bufferlist, 3, + lock, kick_q); } EXPORT_SYMBOL_GPL(vmbus_sendpacket_pagebuffer_ctl); @@ -839,12 +774,10 @@ int vmbus_sendpacket_mpb_desc(struct vmbus_channel *channel, u32 desc_size, void *buffer, u32 bufferlen, u64 requestid) { - int ret; u32 packetlen; u32 packetlen_aligned; struct kvec bufferlist[3]; u64 aligned_data = 0; - bool signal = false; bool lock = channel->acquire_ring_lock; packetlen = desc_size + bufferlen; @@ -865,13 +798,8 @@ int vmbus_sendpacket_mpb_desc(struct vmbus_channel *channel, bufferlist[2].iov_base = &aligned_data; bufferlist[2].iov_len = (packetlen_aligned - packetlen); - ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, - &signal, lock, channel->signal_policy); - - if (ret == 0 && signal) - vmbus_setevent(channel); - - return ret; + return hv_ringbuffer_write(channel, bufferlist, 3, + lock, true); } EXPORT_SYMBOL_GPL(vmbus_sendpacket_mpb_desc); @@ -883,14 +811,12 @@ int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel, struct hv_multipage_buffer *multi_pagebuffer, void *buffer, u32 bufferlen, u64 requestid) { - int ret; struct vmbus_channel_packet_multipage_buffer desc; u32 descsize; u32 packetlen; u32 packetlen_aligned; struct kvec bufferlist[3]; u64 aligned_data = 0; - bool signal = false; bool lock = channel->acquire_ring_lock; u32 pfncount = NUM_PAGES_SPANNED(multi_pagebuffer->offset, multi_pagebuffer->len); @@ -930,13 +856,8 @@ int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel, bufferlist[2].iov_base = &aligned_data; bufferlist[2].iov_len = (packetlen_aligned - packetlen); - ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, - &signal, lock, channel->signal_policy); - - if (ret == 0 && signal) - vmbus_setevent(channel); - - return ret; + return hv_ringbuffer_write(channel, bufferlist, 3, + lock, true); } EXPORT_SYMBOL_GPL(vmbus_sendpacket_multipagebuffer); |