Staging: hv: fix smp problems in the hyperv core code

This fixes a number of SMP problems that were in the hyperv core code.

Patch originally written by K. Y. Srinivasan <ksrinivasan@novell.com>
but forward ported to the latest in-kernel code and tweaked slightly by
me.

Novell, Inc. hereby disclaims all copyright in any derivative work
copyright associated with this patch.

Signed-off-by: K. Y. Srinivasan <ksrinivasan@novell.com>
Cc: Hank Janssen <hjanssen@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>.
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

3 files changed, 35 insertions, 33 deletions

diff --git a/drivers/staging/hv/Hv.c b/drivers/staging/hv/Hv.c
index c5b6613f2f2f..c2809f2a2ce0 100644
--- a/drivers/staging/hv/Hv.c
+++ b/drivers/staging/hv/Hv.c
@@ -386,7 +386,7 @@ u16 HvSignalEvent(void)
  * retrieve the initialized message and event pages.  Otherwise, we create and
  * initialize the message and event pages.
  */
-int HvSynicInit(u32 irqVector)
+void HvSynicInit(void *irqarg)
 {
         u64 version;
         union hv_synic_simp simp;
@@ -394,13 +394,14 @@ int HvSynicInit(u32 irqVector)
         union hv_synic_sint sharedSint;
         union hv_synic_scontrol sctrl;
         u64 guestID;
-        int ret = 0;
+        u32 irqVector = *((u32 *)(irqarg));
+        int cpu = smp_processor_id();
 
         DPRINT_ENTER(VMBUS);
 
         if (!gHvContext.HypercallPage) {
                 DPRINT_EXIT(VMBUS);
-                return ret;
+                return;
         }
 
         /* Check the version */
@@ -425,27 +426,27 @@ int HvSynicInit(u32 irqVector)
                  */
                 rdmsrl(HV_X64_MSR_GUEST_OS_ID, guestID);
                 if (guestID == HV_LINUX_GUEST_ID) {
-                        gHvContext.synICMessagePage[0] =
+                        gHvContext.synICMessagePage[cpu] =
                                 phys_to_virt(simp.BaseSimpGpa << PAGE_SHIFT);
-                        gHvContext.synICEventPage[0] =
+                        gHvContext.synICEventPage[cpu] =
                                 phys_to_virt(siefp.BaseSiefpGpa << PAGE_SHIFT);
                 } else {
                         DPRINT_ERR(VMBUS, "unknown guest id!!");
                         goto Cleanup;
                 }
                 DPRINT_DBG(VMBUS, "MAPPED: Simp: %p, Sifep: %p",
-                           gHvContext.synICMessagePage[0],
-                           gHvContext.synICEventPage[0]);
+                           gHvContext.synICMessagePage[cpu],
+                           gHvContext.synICEventPage[cpu]);
         } else {
-                gHvContext.synICMessagePage[0] = osd_PageAlloc(1);
-                if (gHvContext.synICMessagePage[0] == NULL) {
+                gHvContext.synICMessagePage[cpu] = (void *)get_zeroed_page(GFP_ATOMIC);
+                if (gHvContext.synICMessagePage[cpu] == NULL) {
                         DPRINT_ERR(VMBUS,
                                    "unable to allocate SYNIC message page!!");
                         goto Cleanup;
                 }
 
-                gHvContext.synICEventPage[0] = osd_PageAlloc(1);
-                if (gHvContext.synICEventPage[0] == NULL) {
+                gHvContext.synICEventPage[cpu] = (void *)get_zeroed_page(GFP_ATOMIC);
+                if (gHvContext.synICEventPage[cpu] == NULL) {
                         DPRINT_ERR(VMBUS,
                                    "unable to allocate SYNIC event page!!");
                         goto Cleanup;
@@ -454,7 +455,7 @@ int HvSynicInit(u32 irqVector)
                 /* Setup the Synic's message page */
                 rdmsrl(HV_X64_MSR_SIMP, simp.AsUINT64);
                 simp.SimpEnabled = 1;
-                simp.BaseSimpGpa = virt_to_phys(gHvContext.synICMessagePage[0])
+                simp.BaseSimpGpa = virt_to_phys(gHvContext.synICMessagePage[cpu])
                                         >> PAGE_SHIFT;
 
                 DPRINT_DBG(VMBUS, "HV_X64_MSR_SIMP msr set to: %llx",
@@ -465,7 +466,7 @@ int HvSynicInit(u32 irqVector)
                 /* Setup the Synic's event page */
                 rdmsrl(HV_X64_MSR_SIEFP, siefp.AsUINT64);
                 siefp.SiefpEnabled = 1;
-                siefp.BaseSiefpGpa = virt_to_phys(gHvContext.synICEventPage[0])
+                siefp.BaseSiefpGpa = virt_to_phys(gHvContext.synICEventPage[cpu])
                                         >> PAGE_SHIFT;
 
                 DPRINT_DBG(VMBUS, "HV_X64_MSR_SIEFP msr set to: %llx",
@@ -501,32 +502,30 @@ int HvSynicInit(u32 irqVector)
 
         DPRINT_EXIT(VMBUS);
 
-        return ret;
+        return;
 
 Cleanup:
-        ret = -1;
-
         if (gHvContext.GuestId == HV_LINUX_GUEST_ID) {
-                if (gHvContext.synICEventPage[0])
-                        osd_PageFree(gHvContext.synICEventPage[0], 1);
+                if (gHvContext.synICEventPage[cpu])
+                        osd_PageFree(gHvContext.synICEventPage[cpu], 1);
 
-                if (gHvContext.synICMessagePage[0])
-                        osd_PageFree(gHvContext.synICMessagePage[0], 1);
+                if (gHvContext.synICMessagePage[cpu])
+                        osd_PageFree(gHvContext.synICMessagePage[cpu], 1);
         }
 
         DPRINT_EXIT(VMBUS);
-
-        return ret;
+        return;
 }
 
 /**
  * HvSynicCleanup - Cleanup routine for HvSynicInit().
  */
-void HvSynicCleanup(void)
+void HvSynicCleanup(void *arg)
 {
         union hv_synic_sint sharedSint;
         union hv_synic_simp simp;
         union hv_synic_siefp siefp;
+        int cpu = smp_processor_id();
 
         DPRINT_ENTER(VMBUS);
 
@@ -539,6 +538,7 @@ void HvSynicCleanup(void)
 
         sharedSint.Masked = 1;
 
+        /* Need to correctly cleanup in the case of SMP!!! */
         /* Disable the interrupt */
         wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, sharedSint.AsUINT64);
 
@@ -560,8 +560,8 @@ void HvSynicCleanup(void)
 
                 wrmsrl(HV_X64_MSR_SIEFP, siefp.AsUINT64);
 
-                osd_PageFree(gHvContext.synICMessagePage[0], 1);
-                osd_PageFree(gHvContext.synICEventPage[0], 1);
+                osd_PageFree(gHvContext.synICMessagePage[cpu], 1);
+                osd_PageFree(gHvContext.synICEventPage[cpu], 1);
         }
 
         DPRINT_EXIT(VMBUS);
diff --git a/drivers/staging/hv/Hv.h b/drivers/staging/hv/Hv.h
index 5379e4bfc56e..fce4b5cdac30 100644
--- a/drivers/staging/hv/Hv.h
+++ b/drivers/staging/hv/Hv.h
@@ -93,7 +93,7 @@ static const struct hv_guid VMBUS_SERVICE_ID = {
         },
 };
 
-#define MAX_NUM_CPUS    1
+#define MAX_NUM_CPUS    32
 
 
 struct hv_input_signal_event_buffer {
@@ -137,8 +137,8 @@ extern u16 HvPostMessage(union hv_connection_id connectionId,
 
 extern u16 HvSignalEvent(void);
 
-extern int HvSynicInit(u32 irqVector);
+extern void HvSynicInit(void *irqarg);
 
-extern void HvSynicCleanup(void);
+extern void HvSynicCleanup(void *arg);
 
 #endif /* __HV_H__ */
diff --git a/drivers/staging/hv/Vmbus.c b/drivers/staging/hv/Vmbus.c
index a4dd06f6d459..35a023e9f9d1 100644
--- a/drivers/staging/hv/Vmbus.c
+++ b/drivers/staging/hv/Vmbus.c
@@ -129,7 +129,7 @@ static int VmbusOnDeviceAdd(struct hv_device *dev, void *AdditionalInfo)
 
         /* strcpy(dev->name, "vmbus"); */
         /* SynIC setup... */
-        ret = HvSynicInit(*irqvector);
+        on_each_cpu(HvSynicInit, (void *)irqvector, 1);
 
         /* Connect to VMBus in the root partition */
         ret = VmbusConnect();
@@ -150,7 +150,7 @@ static int VmbusOnDeviceRemove(struct hv_device *dev)
         DPRINT_ENTER(VMBUS);
         VmbusChannelReleaseUnattachedChannels();
         VmbusDisconnect();
-        HvSynicCleanup();
+        on_each_cpu(HvSynicCleanup, NULL, 1);
         DPRINT_EXIT(VMBUS);
 
         return ret;
@@ -173,7 +173,8 @@ static void VmbusOnCleanup(struct hv_driver *drv)
  */
 static void VmbusOnMsgDPC(struct hv_driver *drv)
 {
-        void *page_addr = gHvContext.synICMessagePage[0];
+        int cpu = smp_processor_id();
+        void *page_addr = gHvContext.synICMessagePage[cpu];
         struct hv_message *msg = (struct hv_message *)page_addr +
                                   VMBUS_MESSAGE_SINT;
         struct hv_message *copied;
@@ -230,11 +231,12 @@ static void VmbusOnEventDPC(struct hv_driver *drv)
 static int VmbusOnISR(struct hv_driver *drv)
 {
         int ret = 0;
+        int cpu = smp_processor_id();
         void *page_addr;
         struct hv_message *msg;
         union hv_synic_event_flags *event;
 
-        page_addr = gHvContext.synICMessagePage[0];
+        page_addr = gHvContext.synICMessagePage[cpu];
         msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT;
 
         DPRINT_ENTER(VMBUS);
@@ -248,7 +250,7 @@ static int VmbusOnISR(struct hv_driver *drv)
         }
 
         /* TODO: Check if there are events to be process */
-        page_addr = gHvContext.synICEventPage[0];
+        page_addr = gHvContext.synICEventPage[cpu];
         event = (union hv_synic_event_flags *)page_addr + VMBUS_MESSAGE_SINT;
 
         /* Since we are a child, we only need to check bit 0 */