Move definitions related to the Hyper-V SynIC event flags to a header
where they can be consumed by userspace.

While doing so, also clean up their use by switching to standard bitops
and struct-based dereferencing.  The latter is also done for message
pages.

Signed-off-by: Roman Kagan <rka...@virtuozzo.com>
---
 arch/x86/include/uapi/asm/hyperv.h | 13 +++++++++
 drivers/hv/hyperv_vmbus.h          | 24 ++--------------
 drivers/hv/channel_mgmt.c          | 10 +++----
 drivers/hv/connection.c            | 47 ++++++++++---------------------
 drivers/hv/vmbus_drv.c             | 57 ++++++++++++++------------------------
 5 files changed, 54 insertions(+), 97 deletions(-)

diff --git a/arch/x86/include/uapi/asm/hyperv.h 
b/arch/x86/include/uapi/asm/hyperv.h
index 6098ab5..af542a3 100644
--- a/arch/x86/include/uapi/asm/hyperv.h
+++ b/arch/x86/include/uapi/asm/hyperv.h
@@ -363,4 +363,17 @@ struct hv_timer_message_payload {
 #define HV_STIMER_AUTOENABLE           (1ULL << 3)
 #define HV_STIMER_SINT(config)         (__u8)(((config) >> 16) & 0x0F)
 
+/* Define synthetic interrupt controller flag constants. */
+#define HV_EVENT_FLAGS_COUNT           (256 * 8)
+
+/* Define the synthetic interrupt controller event flags format. */
+struct hv_synic_event_flags {
+       __u64 flags[HV_EVENT_FLAGS_COUNT / 64];
+};
+
+/* Define the synthetic interrupt flags page layout. */
+struct hv_synic_event_flags_page {
+       struct hv_synic_event_flags sintevent_flags[HV_SYNIC_SINT_COUNT];
+};
+
 #endif
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
index 4516498..4fab154 100644
--- a/drivers/hv/hyperv_vmbus.h
+++ b/drivers/hv/hyperv_vmbus.h
@@ -26,7 +26,6 @@
 #define _HYPERV_VMBUS_H
 
 #include <linux/list.h>
-#include <asm/sync_bitops.h>
 #include <linux/atomic.h>
 #include <linux/hyperv.h>
 
@@ -75,11 +74,6 @@ enum hv_cpuid_function {
 
 #define HV_ANY_VP                      (0xFFFFFFFF)
 
-/* Define synthetic interrupt controller flag constants. */
-#define HV_EVENT_FLAGS_COUNT           (256 * 8)
-#define HV_EVENT_FLAGS_BYTE_COUNT      (256)
-#define HV_EVENT_FLAGS_DWORD_COUNT     (256 / sizeof(u32))
-
 /* Define invalid partition identifier. */
 #define HV_PARTITION_ID_INVALID                ((u64)0x0)
 
@@ -146,20 +140,6 @@ union hv_timer_config {
        };
 };
 
-/* Define the number of message buffers associated with each port. */
-#define HV_PORT_MESSAGE_BUFFER_COUNT   (16)
-
-/* Define the synthetic interrupt controller event flags format. */
-union hv_synic_event_flags {
-       u8 flags8[HV_EVENT_FLAGS_BYTE_COUNT];
-       u32 flags32[HV_EVENT_FLAGS_DWORD_COUNT];
-};
-
-/* Define the synthetic interrupt flags page layout. */
-struct hv_synic_event_flags_page {
-       union hv_synic_event_flags sintevent_flags[HV_SYNIC_SINT_COUNT];
-};
-
 /* Define SynIC control register. */
 union hv_synic_scontrol {
        u64 as_uint64;
@@ -434,8 +414,8 @@ struct hv_context {
 
        bool synic_initialized;
 
-       void *synic_message_page[NR_CPUS];
-       void *synic_event_page[NR_CPUS];
+       struct hv_message_page *synic_message_page[NR_CPUS];
+       struct hv_synic_event_flags_page *synic_event_page[NR_CPUS];
        /*
         * Hypervisor's notion of virtual processor ID is different from
         * Linux' notion of CPU ID. This information can only be retrieved
diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
index 26b4192..49eaae2 100644
--- a/drivers/hv/channel_mgmt.c
+++ b/drivers/hv/channel_mgmt.c
@@ -654,7 +654,6 @@ static void init_vp_index(struct vmbus_channel *channel, 
u16 dev_type)
 static void vmbus_wait_for_unload(void)
 {
        int cpu;
-       void *page_addr;
        struct hv_message *msg;
        struct vmbus_channel_message_header *hdr;
        u32 message_type;
@@ -673,9 +672,8 @@ static void vmbus_wait_for_unload(void)
                        break;
 
                for_each_online_cpu(cpu) {
-                       page_addr = hv_context.synic_message_page[cpu];
-                       msg = (struct hv_message *)page_addr +
-                               VMBUS_MESSAGE_SINT;
+                       msg = &hv_context.synic_message_page[cpu]->
+                                       sint_message[VMBUS_MESSAGE_SINT];
 
                        message_type = READ_ONCE(msg->header.message_type);
                        if (message_type == HVMSG_NONE)
@@ -699,8 +697,8 @@ static void vmbus_wait_for_unload(void)
         * messages after we reconnect.
         */
        for_each_online_cpu(cpu) {
-               page_addr = hv_context.synic_message_page[cpu];
-               msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT;
+               msg = &hv_context.synic_message_page[cpu]->
+                               sint_message[VMBUS_MESSAGE_SINT];
                msg->header.message_type = HVMSG_NONE;
        }
 }
diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
index 6ce8b87..aaa2103 100644
--- a/drivers/hv/connection.c
+++ b/drivers/hv/connection.c
@@ -381,17 +381,12 @@ static void process_chn_event(u32 relid)
  */
 void vmbus_on_event(unsigned long data)
 {
-       u32 dword;
-       u32 maxdword;
-       int bit;
-       u32 relid;
-       u32 *recv_int_page = NULL;
-       void *page_addr;
+       u32 relid, max_relid;
+       unsigned long *recv_int_page;
        int cpu = smp_processor_id();
-       union hv_synic_event_flags *event;
 
        if (vmbus_proto_version < VERSION_WIN8) {
-               maxdword = MAX_NUM_CHANNELS_SUPPORTED >> 5;
+               max_relid = MAX_NUM_CHANNELS_SUPPORTED;
                recv_int_page = vmbus_connection.recv_int_page;
        } else {
                /*
@@ -399,36 +394,22 @@ void vmbus_on_event(unsigned long data)
                 * can be directly checked to get the id of the channel
                 * that has the interrupt pending.
                 */
-               maxdword = HV_EVENT_FLAGS_DWORD_COUNT;
-               page_addr = hv_context.synic_event_page[cpu];
-               event = (union hv_synic_event_flags *)page_addr +
-                                                VMBUS_MESSAGE_SINT;
-               recv_int_page = event->flags32;
+               struct hv_synic_event_flags *event =
+                       &hv_context.synic_event_page[cpu]->
+                               sintevent_flags[VMBUS_MESSAGE_SINT];
+               max_relid = HV_EVENT_FLAGS_COUNT;
+               recv_int_page = (unsigned long *)event->flags;
        }
 
-
-
        /* Check events */
        if (!recv_int_page)
                return;
-       for (dword = 0; dword < maxdword; dword++) {
-               if (!recv_int_page[dword])
-                       continue;
-               for (bit = 0; bit < 32; bit++) {
-                       if (sync_test_and_clear_bit(bit,
-                               (unsigned long *)&recv_int_page[dword])) {
-                               relid = (dword << 5) + bit;
-
-                               if (relid == 0)
-                                       /*
-                                        * Special case - vmbus
-                                        * channel protocol msg
-                                        */
-                                       continue;
-
-                               process_chn_event(relid);
-                       }
-               }
+
+       /* relid == 0 is vmbus channel protocol msg */
+       relid = 1;
+       for_each_set_bit_from(relid, recv_int_page, max_relid) {
+               clear_bit(relid, recv_int_page);
+               process_chn_event(relid);
        }
 }
 
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 230c62e..13dd210 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -872,9 +872,8 @@ static void hv_process_timer_expiration(struct hv_message 
*msg, int cpu)
 void vmbus_on_msg_dpc(unsigned long data)
 {
        int cpu = smp_processor_id();
-       void *page_addr = hv_context.synic_message_page[cpu];
-       struct hv_message *msg = (struct hv_message *)page_addr +
-                                 VMBUS_MESSAGE_SINT;
+       struct hv_message *msg = &hv_context.synic_message_page[cpu]->
+                                       sint_message[VMBUS_MESSAGE_SINT];
        struct vmbus_channel_message_header *hdr;
        struct vmbus_channel_message_table_entry *entry;
        struct onmessage_work_context *ctx;
@@ -911,54 +910,40 @@ void vmbus_on_msg_dpc(unsigned long data)
 static void vmbus_isr(void)
 {
        int cpu = smp_processor_id();
-       void *page_addr;
        struct hv_message *msg;
-       union hv_synic_event_flags *event;
-       bool handled = false;
+       struct hv_synic_event_flags *event;
 
-       page_addr = hv_context.synic_event_page[cpu];
-       if (page_addr == NULL)
+       if (!hv_context.synic_event_page[cpu])
                return;
 
-       event = (union hv_synic_event_flags *)page_addr +
-                                        VMBUS_MESSAGE_SINT;
+       event = &hv_context.synic_event_page[cpu]->
+                       sintevent_flags[VMBUS_MESSAGE_SINT];
        /*
         * Check for events before checking for messages. This is the order
         * in which events and messages are checked in Windows guests on
         * Hyper-V, and the Windows team suggested we do the same.
         */
 
-       if ((vmbus_proto_version == VERSION_WS2008) ||
-               (vmbus_proto_version == VERSION_WIN7)) {
-
+       /* On win8 and above the channel interrupts are signaled directly in
+        * the event page and will be checked in the .event_dpc
+        */
+       if (vmbus_proto_version >= VERSION_WIN8 ||
                /* Since we are a child, we only need to check bit 0 */
-               if (sync_test_and_clear_bit(0,
-                       (unsigned long *) &event->flags32[0])) {
-                       handled = true;
-               }
-       } else {
-               /*
-                * Our host is win8 or above. The signaling mechanism
-                * has changed and we can directly look at the event page.
-                * If bit n is set then we have an interrup on the channel
-                * whose id is n.
-                */
-               handled = true;
-       }
-
-       if (handled)
+           test_and_clear_bit(0, (unsigned long *)event->flags))
                tasklet_schedule(hv_context.event_dpc[cpu]);
 
-
-       page_addr = hv_context.synic_message_page[cpu];
-       msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT;
+       msg = &hv_context.synic_message_page[cpu]->
+                       sint_message[VMBUS_MESSAGE_SINT];
 
        /* Check if there are actual msgs to be processed */
-       if (msg->header.message_type != HVMSG_NONE) {
-               if (msg->header.message_type == HVMSG_TIMER_EXPIRED)
-                       hv_process_timer_expiration(msg, cpu);
-               else
-                       tasklet_schedule(hv_context.msg_dpc[cpu]);
+       switch (READ_ONCE(msg->header.message_type)) {
+       case HVMSG_NONE:
+               break;
+       case HVMSG_TIMER_EXPIRED:
+               hv_process_timer_expiration(msg, cpu);
+               break;
+       default:
+               tasklet_schedule(hv_context.msg_dpc[cpu]);
        }
 
        add_interrupt_randomness(HYPERVISOR_CALLBACK_VECTOR, 0);
-- 
2.9.3

_______________________________________________
devel mailing list
de...@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel

Reply via email to