[PATCH v2 4/4] powerpc/pseries/vas: Disable window open during migration
From: Haren Myneni <haren@linux.ibm.com>
Date: 2022-02-06 02:30:46
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
The current partition migration implementation does not freeze the user space and the user space can continue open VAS windows. So when migration_in_progress flag is enabled, VAS open window API returns -EBUSY. Signed-off-by: Haren Myneni <haren@linux.ibm.com> --- arch/powerpc/platforms/pseries/vas.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/platforms/pseries/vas.c b/arch/powerpc/platforms/pseries/vas.c
index 345d469c3560..ffcf18cfb4e3 100644
--- a/arch/powerpc/platforms/pseries/vas.c
+++ b/arch/powerpc/platforms/pseries/vas.c@@ -30,6 +30,7 @@ static struct hv_vas_cop_feat_caps hv_cop_caps; static struct vas_caps vascaps[VAS_MAX_FEAT_TYPE]; static DEFINE_MUTEX(vas_pseries_mutex); +static bool migration_in_progress; static long hcall_return_busy_check(long rc) {
@@ -356,8 +357,11 @@ static struct vas_window *vas_allocate_window(int vas_id, u64 flags, * same fault IRQ is not freed by the OS before. */ mutex_lock(&vas_pseries_mutex); - rc = allocate_setup_window(txwin, (u64 *)&domain[0], - cop_feat_caps->win_type); + if (migration_in_progress) + rc = -EBUSY; + else + rc = allocate_setup_window(txwin, (u64 *)&domain[0], + cop_feat_caps->win_type); mutex_unlock(&vas_pseries_mutex); if (rc) goto out;
@@ -889,6 +893,11 @@ int vas_migration_handler(int action) mutex_lock(&vas_pseries_mutex); + if (action == VAS_SUSPEND) + migration_in_progress = true; + else + migration_in_progress = false; + for (i = 0; i < VAS_MAX_FEAT_TYPE; i++) { vcaps = &vascaps[i]; caps = &vcaps->caps;
--
2.27.0