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path: root/drivers/pci/controller/pci-hyperv.c
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Diffstat (limited to 'drivers/pci/controller/pci-hyperv.c')
-rw-r--r--drivers/pci/controller/pci-hyperv.c82
1 files changed, 62 insertions, 20 deletions
diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
index 222ff5639ebe..bf40ff09c99d 100644
--- a/drivers/pci/controller/pci-hyperv.c
+++ b/drivers/pci/controller/pci-hyperv.c
@@ -480,6 +480,9 @@ struct hv_pcibus_device {
struct workqueue_struct *wq;
+ /* Highest slot of child device with resources allocated */
+ int wslot_res_allocated;
+
/* hypercall arg, must not cross page boundary */
struct hv_retarget_device_interrupt retarget_msi_interrupt_params;
@@ -2210,10 +2213,8 @@ static void hv_pci_devices_present(struct hv_pcibus_device *hbus,
struct hv_dr_state *dr;
int i;
- dr = kzalloc(offsetof(struct hv_dr_state, func) +
- (sizeof(struct hv_pcidev_description) *
- (relations->device_count)), GFP_NOWAIT);
-
+ dr = kzalloc(struct_size(dr, func, relations->device_count),
+ GFP_NOWAIT);
if (!dr)
return;
@@ -2247,10 +2248,8 @@ static void hv_pci_devices_present2(struct hv_pcibus_device *hbus,
struct hv_dr_state *dr;
int i;
- dr = kzalloc(offsetof(struct hv_dr_state, func) +
- (sizeof(struct hv_pcidev_description) *
- (relations->device_count)), GFP_NOWAIT);
-
+ dr = kzalloc(struct_size(dr, func, relations->device_count),
+ GFP_NOWAIT);
if (!dr)
return;
@@ -2444,9 +2443,8 @@ static void hv_pci_onchannelcallback(void *context)
bus_rel = (struct pci_bus_relations *)buffer;
if (bytes_recvd <
- offsetof(struct pci_bus_relations, func) +
- (sizeof(struct pci_function_description) *
- (bus_rel->device_count))) {
+ struct_size(bus_rel, func,
+ bus_rel->device_count)) {
dev_err(&hbus->hdev->device,
"bus relations too small\n");
break;
@@ -2459,9 +2457,8 @@ static void hv_pci_onchannelcallback(void *context)
bus_rel2 = (struct pci_bus_relations2 *)buffer;
if (bytes_recvd <
- offsetof(struct pci_bus_relations2, func) +
- (sizeof(struct pci_function_description2) *
- (bus_rel2->device_count))) {
+ struct_size(bus_rel2, func,
+ bus_rel2->device_count)) {
dev_err(&hbus->hdev->device,
"bus relations v2 too small\n");
break;
@@ -2748,6 +2745,8 @@ static void hv_free_config_window(struct hv_pcibus_device *hbus)
vmbus_free_mmio(hbus->mem_config->start, PCI_CONFIG_MMIO_LENGTH);
}
+static int hv_pci_bus_exit(struct hv_device *hdev, bool keep_devs);
+
/**
* hv_pci_enter_d0() - Bring the "bus" into the D0 power state
* @hdev: VMBus's tracking struct for this root PCI bus
@@ -2760,8 +2759,10 @@ static int hv_pci_enter_d0(struct hv_device *hdev)
struct pci_bus_d0_entry *d0_entry;
struct hv_pci_compl comp_pkt;
struct pci_packet *pkt;
+ bool retry = true;
int ret;
+enter_d0_retry:
/*
* Tell the host that the bus is ready to use, and moved into the
* powered-on state. This includes telling the host which region
@@ -2788,6 +2789,38 @@ static int hv_pci_enter_d0(struct hv_device *hdev)
if (ret)
goto exit;
+ /*
+ * In certain case (Kdump) the pci device of interest was
+ * not cleanly shut down and resource is still held on host
+ * side, the host could return invalid device status.
+ * We need to explicitly request host to release the resource
+ * and try to enter D0 again.
+ */
+ if (comp_pkt.completion_status < 0 && retry) {
+ retry = false;
+
+ dev_err(&hdev->device, "Retrying D0 Entry\n");
+
+ /*
+ * Hv_pci_bus_exit() calls hv_send_resource_released()
+ * to free up resources of its child devices.
+ * In the kdump kernel we need to set the
+ * wslot_res_allocated to 255 so it scans all child
+ * devices to release resources allocated in the
+ * normal kernel before panic happened.
+ */
+ hbus->wslot_res_allocated = 255;
+
+ ret = hv_pci_bus_exit(hdev, true);
+
+ if (ret == 0) {
+ kfree(pkt);
+ goto enter_d0_retry;
+ }
+ dev_err(&hdev->device,
+ "Retrying D0 failed with ret %d\n", ret);
+ }
+
if (comp_pkt.completion_status < 0) {
dev_err(&hdev->device,
"PCI Pass-through VSP failed D0 Entry with status %x\n",
@@ -2859,7 +2892,7 @@ static int hv_send_resources_allocated(struct hv_device *hdev)
struct hv_pci_dev *hpdev;
struct pci_packet *pkt;
size_t size_res;
- u32 wslot;
+ int wslot;
int ret;
size_res = (hbus->protocol_version < PCI_PROTOCOL_VERSION_1_2)
@@ -2912,6 +2945,8 @@ static int hv_send_resources_allocated(struct hv_device *hdev)
comp_pkt.completion_status);
break;
}
+
+ hbus->wslot_res_allocated = wslot;
}
kfree(pkt);
@@ -2930,10 +2965,10 @@ static int hv_send_resources_released(struct hv_device *hdev)
struct hv_pcibus_device *hbus = hv_get_drvdata(hdev);
struct pci_child_message pkt;
struct hv_pci_dev *hpdev;
- u32 wslot;
+ int wslot;
int ret;
- for (wslot = 0; wslot < 256; wslot++) {
+ for (wslot = hbus->wslot_res_allocated; wslot >= 0; wslot--) {
hpdev = get_pcichild_wslot(hbus, wslot);
if (!hpdev)
continue;
@@ -2948,8 +2983,12 @@ static int hv_send_resources_released(struct hv_device *hdev)
VM_PKT_DATA_INBAND, 0);
if (ret)
return ret;
+
+ hbus->wslot_res_allocated = wslot - 1;
}
+ hbus->wslot_res_allocated = -1;
+
return 0;
}
@@ -3049,6 +3088,7 @@ static int hv_pci_probe(struct hv_device *hdev,
if (!hbus)
return -ENOMEM;
hbus->state = hv_pcibus_init;
+ hbus->wslot_res_allocated = -1;
/*
* The PCI bus "domain" is what is called "segment" in ACPI and other
@@ -3148,7 +3188,7 @@ static int hv_pci_probe(struct hv_device *hdev,
ret = hv_pci_allocate_bridge_windows(hbus);
if (ret)
- goto free_irq_domain;
+ goto exit_d0;
ret = hv_send_resources_allocated(hdev);
if (ret)
@@ -3166,6 +3206,8 @@ static int hv_pci_probe(struct hv_device *hdev,
free_windows:
hv_pci_free_bridge_windows(hbus);
+exit_d0:
+ (void) hv_pci_bus_exit(hdev, true);
free_irq_domain:
irq_domain_remove(hbus->irq_domain);
free_fwnode:
@@ -3185,7 +3227,7 @@ free_bus:
return ret;
}
-static int hv_pci_bus_exit(struct hv_device *hdev, bool hibernating)
+static int hv_pci_bus_exit(struct hv_device *hdev, bool keep_devs)
{
struct hv_pcibus_device *hbus = hv_get_drvdata(hdev);
struct {
@@ -3203,7 +3245,7 @@ static int hv_pci_bus_exit(struct hv_device *hdev, bool hibernating)
if (hdev->channel->rescind)
return 0;
- if (!hibernating) {
+ if (!keep_devs) {
/* Delete any children which might still exist. */
dr = kzalloc(sizeof(*dr), GFP_KERNEL);
if (dr && hv_pci_start_relations_work(hbus, dr))