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-rw-r--r--drivers/hv/channel.c99
-rw-r--r--drivers/hv/hyperv_vmbus.h6
-rw-r--r--drivers/hv/ring_buffer.c30
-rw-r--r--include/linux/hyperv.h1
4 files changed, 35 insertions, 101 deletions
diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index 5e482d7f60cb..8a8148f7b842 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);
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
index bdab7e7f2a15..2d42ebe2af6c 100644
--- a/drivers/hv/hyperv_vmbus.h
+++ b/drivers/hv/hyperv_vmbus.h
@@ -527,10 +527,10 @@ int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info,
void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info);
-int hv_ringbuffer_write(struct hv_ring_buffer_info *ring_info,
+int hv_ringbuffer_write(struct vmbus_channel *channel,
struct kvec *kv_list,
- u32 kv_count, bool *signal, bool lock,
- enum hv_signal_policy policy);
+ u32 kv_count, bool lock,
+ bool kick_q);
int hv_ringbuffer_read(struct hv_ring_buffer_info *inring_info,
void *buffer, u32 buflen, u32 *buffer_actual_len,
diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
index 5d11d93eedf4..4af71306d0ff 100644
--- a/drivers/hv/ring_buffer.c
+++ b/drivers/hv/ring_buffer.c
@@ -66,14 +66,25 @@ u32 hv_end_read(struct hv_ring_buffer_info *rbi)
* once the ring buffer is empty, it will clear the
* interrupt_mask and re-check to see if new data has
* arrived.
+ *
+ * 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.
*/
-static bool hv_need_to_signal(u32 old_write, struct hv_ring_buffer_info *rbi,
- enum hv_signal_policy policy)
+static void hv_signal_on_write(u32 old_write, struct vmbus_channel *channel,
+ bool kick_q)
{
+ struct hv_ring_buffer_info *rbi = &channel->outbound;
+
virt_mb();
if (READ_ONCE(rbi->ring_buffer->interrupt_mask))
- return false;
+ return;
/* check interrupt_mask before read_index */
virt_rmb();
@@ -82,9 +93,9 @@ static bool hv_need_to_signal(u32 old_write, struct hv_ring_buffer_info *rbi,
* ring transitions from being empty to non-empty.
*/
if (old_write == READ_ONCE(rbi->ring_buffer->read_index))
- return true;
+ vmbus_setevent(channel);
- return false;
+ return;
}
/* Get the next write location for the specified ring buffer. */
@@ -273,9 +284,9 @@ void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info)
}
/* Write to the ring buffer. */
-int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info,
- struct kvec *kv_list, u32 kv_count, bool *signal, bool lock,
- enum hv_signal_policy policy)
+int hv_ringbuffer_write(struct vmbus_channel *channel,
+ struct kvec *kv_list, u32 kv_count, bool lock,
+ bool kick_q)
{
int i = 0;
u32 bytes_avail_towrite;
@@ -285,6 +296,7 @@ int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info,
u32 old_write;
u64 prev_indices = 0;
unsigned long flags = 0;
+ struct hv_ring_buffer_info *outring_info = &channel->outbound;
for (i = 0; i < kv_count; i++)
totalbytes_towrite += kv_list[i].iov_len;
@@ -337,7 +349,7 @@ int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info,
if (lock)
spin_unlock_irqrestore(&outring_info->ring_lock, flags);
- *signal = hv_need_to_signal(old_write, outring_info, policy);
+ hv_signal_on_write(old_write, channel, kick_q);
return 0;
}
diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index 42ae6a5a2538..8cf78ed96747 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -1454,6 +1454,7 @@ void hv_event_tasklet_enable(struct vmbus_channel *channel);
void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid);
+void vmbus_setevent(struct vmbus_channel *channel);
/*
* Negotiated version with the Host.
*/
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-01 18:25:46 +0000