This patch is to add callback to handle fault event reported by
IOMMU driver. Callback stores fault into an array and notify userspace
via eventfd to read fault info.
Signed-off-by: Lan Tianyu <tianyu.lan@xxxxxxxxx>
---
drivers/vfio/vfio_iommu_type1.c | 30 ++++++++++++++++++++++++++++++
include/linux/iommu.h | 7 +++++++
include/uapi/linux/vfio.h | 7 +++++++
3 files changed, 44 insertions(+)
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 46674ea..dc434a3 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -56,6 +56,8 @@
MODULE_PARM_DESC(disable_hugepages,
"Disable VFIO IOMMU support for IOMMU hugepages.");
+#define NR_IOMMU_FAULT_INFO 10
+
struct vfio_iommu {
struct list_head domain_list;
struct vfio_domain *external_domain; /* domain for external user */
@@ -64,6 +66,9 @@ struct vfio_iommu {
struct blocking_notifier_head notifier;
struct eventfd_ctx *iommu_fault_fd;
struct mutex fault_lock;
+ struct vfio_iommu_fault_info fault_info[NR_IOMMU_FAULT_INFO];
+ struct blocking_notifier_head iommu_fault_notifier;
+ u8 fault_count;
bool v2;
bool nesting;
};
@@ -1456,6 +1461,7 @@ static void *vfio_iommu_type1_open(unsigned long arg)
iommu->dma_list = RB_ROOT;
mutex_init(&iommu->lock);
mutex_init(&iommu->fault_lock);
+ iommu->fault_count = 0;
BLOCKING_INIT_NOTIFIER_HEAD(&iommu->notifier);
return iommu;
@@ -1516,6 +1522,30 @@ static int vfio_domains_have_iommu_cache(struct vfio_iommu *iommu)
return ret;
}
+static int vfio_iommu_fault_event_notifier(struct notifier_block *nb,
+ struct iommu_fault_info *fault_info,
+ void *data)
+{
+ struct vfio_iommu *iommu = data;
+ struct vfio_iommu_fault_info *info;
+
+ mutex_lock(&iommu->fault_lock);
+
+ info = &iommu->fault_info[iommu->fault_count];
+ info->addr = fault_info->addr;
+ info->sid = fault_info->sid;
+ info->fault_reason = fault_info->fault_reason;
+ info->is_write = fault_info->is_write;
+
+ iommu->fault_count++;
+
+ if (iommu->iommu_fault_fd)
+ eventfd_signal(iommu->iommu_fault_fd, 1);
+
+ mutex_unlock(&iommu->fault_lock);
+ return 0;
+}
+
static long vfio_iommu_type1_ioctl(void *iommu_data,
unsigned int cmd, unsigned long arg)
{
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 0ff5111..b6a7bdb 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -86,6 +86,13 @@ struct iommu_domain {
void *iova_cookie;
};
+struct iommu_fault_info {
+ __u64 addr;
+ __u16 sid;
+ __u8 fault_reason;
+ __u8 is_write:1;
+};
+
enum iommu_cap {
IOMMU_CAP_CACHE_COHERENCY, /* IOMMU can enforce cache coherent DMA
transactions */
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h
index 8616334..da359dd 100644
--- a/include/uapi/linux/vfio.h
+++ b/include/uapi/linux/vfio.h
@@ -562,6 +562,13 @@ struct vfio_iommu_type1_set_fault_eventfd {
#define VFIO_IOMMU_SET_FAULT_EVENTFD _IO(VFIO_TYPE, VFIO_BASE + 17)
+struct vfio_iommu_fault_info {
+ __u64 addr;
+ __u16 sid;
+ __u8 fault_reason;
+ __u8 is_write:1;
+};
+
/* -------- Additional API for SPAPR TCE (Server POWERPC) IOMMU -------- */
/*
--
1.8.3.1
