[PATCH 3/7] Drivers: hv: vmbus: Split hv_synic_init/cleanup into regs and timer settings

Dexuan Cui
2019-07-09T05:31:29Z

There is only one functional change: the unnecessary check
"if (sctrl.enable != 1) return -EFAULT;" is removed, because when we're in
hv_synic_cleanup(), we're absolutely sure sctrl.enable must be 1.

The new functions hv_synic_disable/enable_regs() will be used by a later patch
to support hibernation.

Signed-off-by: Dexuan Cui <decui@microsoft.com>
---
drivers/hv/hv.c | 66 ++++++++++++++++++++++++++---------------------
drivers/hv/hyperv_vmbus.h | 2 ++
2 files changed, 39 insertions(+), 29 deletions(-)

diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
index 6188fb7..fcc5279 100644
--- a/drivers/hv/hv.c
+++ b/drivers/hv/hv.c
@@ -154,7 +154,7 @@ void hv_synic_free(void)
* retrieve the initialized message and event pages. Otherwise, we create and
* initialize the message and event pages.
*/
-int hv_synic_init(unsigned int cpu)
+void hv_synic_enable_regs(unsigned int cpu)
{
struct hv_per_cpu_context *hv_cpu
= per_cpu_ptr(hv_context.cpu_context, cpu);
@@ -196,6 +196,11 @@ int hv_synic_init(unsigned int cpu)
sctrl.enable = 1;

hv_set_synic_state(sctrl.as_uint64);
+}
+
+int hv_synic_init(unsigned int cpu)
+{
+ hv_synic_enable_regs(cpu);

hv_stimer_init(cpu);

@@ -205,20 +210,45 @@ int hv_synic_init(unsigned int cpu)
/*
* hv_synic_cleanup - Cleanup routine for hv_synic_init().
*/
-int hv_synic_cleanup(unsigned int cpu)
+void hv_synic_disable_regs(unsigned int cpu)
{
union hv_synic_sint shared_sint;
union hv_synic_simp simp;
union hv_synic_siefp siefp;
union hv_synic_scontrol sctrl;
+
+ hv_get_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+
+ shared_sint.masked = 1;
+
+ /* Need to correctly cleanup in the case of SMP!!! */
+ /* Disable the interrupt */
+ hv_set_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
+
+ hv_get_simp(simp.as_uint64);
+ simp.simp_enabled = 0;
+ simp.base_simp_gpa = 0;
+
+ hv_set_simp(simp.as_uint64);
+
+ hv_get_siefp(siefp.as_uint64);
+ siefp.siefp_enabled = 0;
+ siefp.base_siefp_gpa = 0;
+
+ hv_set_siefp(siefp.as_uint64);
+
+ /* Disable the global synic bit */
+ hv_get_synic_state(sctrl.as_uint64);
+ sctrl.enable = 0;
+ hv_set_synic_state(sctrl.as_uint64);
+}
+
+int hv_synic_cleanup(unsigned int cpu)
+{
struct vmbus_channel *channel, *sc;
bool channel_found = false;
unsigned long flags;

- hv_get_synic_state(sctrl.as_uint64);
- if (sctrl.enable != 1)
- return -EFAULT;
-
/*
* Search for channels which are bound to the CPU we're about to
* cleanup. In case we find one and vmbus is still connected we need to
@@ -249,29 +279,7 @@ int hv_synic_cleanup(unsigned int cpu)

hv_stimer_cleanup(cpu);

- hv_get_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
-
- shared_sint.masked = 1;
-
- /* Need to correctly cleanup in the case of SMP!!! */
- /* Disable the interrupt */
- hv_set_synint_state(VMBUS_MESSAGE_SINT, shared_sint.as_uint64);
-
- hv_get_simp(simp.as_uint64);
- simp.simp_enabled = 0;
- simp.base_simp_gpa = 0;
-
- hv_set_simp(simp.as_uint64);
-
- hv_get_siefp(siefp.as_uint64);
- siefp.siefp_enabled = 0;
- siefp.base_siefp_gpa = 0;
-
- hv_set_siefp(siefp.as_uint64);
-
- /* Disable the global synic bit */
- sctrl.enable = 0;
- hv_set_synic_state(sctrl.as_uint64);
+ hv_synic_disable_regs(cpu);

return 0;
}
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
index 362e70e..26ea161 100644
--- a/drivers/hv/hyperv_vmbus.h
+++ b/drivers/hv/hyperv_vmbus.h
@@ -171,8 +171,10 @@ extern int hv_post_message(union hv_connection_id connection_id,

extern void hv_synic_free(void);

+extern void hv_synic_enable_regs(unsigned int cpu);
extern int hv_synic_init(unsigned int cpu);

+extern void hv_synic_disable_regs(unsigned int cpu);
extern int hv_synic_cleanup(unsigned int cpu);

/* Interface */
--
1.8.3.1