1 files changed, 305 insertions, 97 deletions

diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c
index c8b423c3c26e..3ecc5059f92b 100644
--- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
@@ -36,11 +36,13 @@
  * PCIe Root Port                        PCI EP
  */
 
+#include <linux/atomic.h>
 #include <linux/delay.h>
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/slab.h>
 
+#include <linux/pci-ep-msi.h>
 #include <linux/pci-epc.h>
 #include <linux/pci-epf.h>
 #include <linux/ntb.h>
@@ -70,9 +72,11 @@ static struct workqueue_struct *kpcintb_workqueue;
 enum epf_ntb_bar {
 	BAR_CONFIG,
 	BAR_DB,
-	BAR_MW0,
 	BAR_MW1,
 	BAR_MW2,
+	BAR_MW3,
+	BAR_MW4,
+	VNTB_BAR_NUM,
 };
 
 /*
@@ -124,15 +128,16 @@ struct epf_ntb {
 	u32 db_count;
 	u32 spad_count;
 	u64 mws_size[MAX_MW];
-	u64 db;
+	atomic64_t db;
 	u32 vbus_number;
 	u16 vntb_pid;
 	u16 vntb_vid;
 
 	bool linkup;
+	bool msi_doorbell;
 	u32 spad_size;
 
-	enum pci_barno epf_ntb_bar[6];
+	enum pci_barno epf_ntb_bar[VNTB_BAR_NUM];
 
 	struct epf_ntb_ctrl *reg;
 
@@ -256,9 +261,9 @@ static void epf_ntb_cmd_handler(struct work_struct *work)
 
 	ntb = container_of(work, struct epf_ntb, cmd_handler.work);
 
-	for (i = 1; i < ntb->db_count; i++) {
+	for (i = 1; i < ntb->db_count && !ntb->msi_doorbell; i++) {
 		if (ntb->epf_db[i]) {
-			ntb->db |= 1 << (i - 1);
+			atomic64_or(1 << (i - 1), &ntb->db);
 			ntb_db_event(&ntb->ntb, i);
 			ntb->epf_db[i] = 0;
 		}
@@ -317,7 +322,21 @@ static void epf_ntb_cmd_handler(struct work_struct *work)
 
 reset_handler:
 	queue_delayed_work(kpcintb_workqueue, &ntb->cmd_handler,
-			   msecs_to_jiffies(5));
+			   ntb->msi_doorbell ? msecs_to_jiffies(500) : msecs_to_jiffies(5));
+}
+
+static irqreturn_t epf_ntb_doorbell_handler(int irq, void *data)
+{
+	struct epf_ntb *ntb = data;
+	int i;
+
+	for (i = 1; i < ntb->db_count; i++)
+		if (irq == ntb->epf->db_msg[i].virq) {
+			atomic64_or(1 << (i - 1), &ntb->db);
+			ntb_db_event(&ntb->ntb, i);
+		}
+
+	return IRQ_HANDLED;
 }
 
 /**
@@ -408,11 +427,9 @@ static void epf_ntb_config_spad_bar_free(struct epf_ntb *ntb)
  */
 static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
 {
-	size_t align;
 	enum pci_barno barno;
 	struct epf_ntb_ctrl *ctrl;
 	u32 spad_size, ctrl_size;
-	u64 size;
 	struct pci_epf *epf = ntb->epf;
 	struct device *dev = &epf->dev;
 	u32 spad_count;
@@ -422,31 +439,13 @@ static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb)
 								epf->func_no,
 								epf->vfunc_no);
 	barno = ntb->epf_ntb_bar[BAR_CONFIG];
-	size = epc_features->bar_fixed_size[barno];
-	align = epc_features->align;
-
-	if ((!IS_ALIGNED(size, align)))
-		return -EINVAL;
-
 	spad_count = ntb->spad_count;
 
-	ctrl_size = sizeof(struct epf_ntb_ctrl);
+	ctrl_size = ALIGN(sizeof(struct epf_ntb_ctrl), sizeof(u32));
 	spad_size = 2 * spad_count * sizeof(u32);
 
-	if (!align) {
-		ctrl_size = roundup_pow_of_two(ctrl_size);
-		spad_size = roundup_pow_of_two(spad_size);
-	} else {
-		ctrl_size = ALIGN(ctrl_size, align);
-		spad_size = ALIGN(spad_size, align);
-	}
-
-	if (!size)
-		size = ctrl_size + spad_size;
-	else if (size < ctrl_size + spad_size)
-		return -EINVAL;
-
-	base = pci_epf_alloc_space(epf, size, barno, align, 0);
+	base = pci_epf_alloc_space(epf, ctrl_size + spad_size,
+				   barno, epc_features, 0);
 	if (!base) {
 		dev_err(dev, "Config/Status/SPAD alloc region fail\n");
 		return -ENOMEM;
@@ -518,6 +517,94 @@ static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)
 	return 0;
 }
 
+static int epf_ntb_db_bar_init_msi_doorbell(struct epf_ntb *ntb,
+					    struct pci_epf_bar *db_bar,
+					    const struct pci_epc_features *epc_features,
+					    enum pci_barno barno)
+{
+	struct pci_epf *epf = ntb->epf;
+	dma_addr_t low, high;
+	struct msi_msg *msg;
+	size_t sz;
+	int ret;
+	int i;
+
+	ret = pci_epf_alloc_doorbell(epf,  ntb->db_count);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < ntb->db_count; i++) {
+		ret = request_irq(epf->db_msg[i].virq, epf_ntb_doorbell_handler,
+				  0, "pci_epf_vntb_db", ntb);
+
+		if (ret) {
+			dev_err(&epf->dev,
+				"Failed to request doorbell IRQ: %d\n",
+				epf->db_msg[i].virq);
+			goto err_free_irq;
+		}
+	}
+
+	msg = &epf->db_msg[0].msg;
+
+	high = 0;
+	low = (u64)msg->address_hi << 32 | msg->address_lo;
+
+	for (i = 0; i < ntb->db_count; i++) {
+		struct msi_msg *msg = &epf->db_msg[i].msg;
+		dma_addr_t addr = (u64)msg->address_hi << 32 | msg->address_lo;
+
+		low = min(low, addr);
+		high = max(high, addr);
+	}
+
+	sz = high - low + sizeof(u32);
+
+	ret = pci_epf_assign_bar_space(epf, sz, barno, epc_features, 0, low);
+	if (ret) {
+		dev_err(&epf->dev, "Failed to assign Doorbell BAR space\n");
+		goto err_free_irq;
+	}
+
+	ret = pci_epc_set_bar(ntb->epf->epc, ntb->epf->func_no,
+			      ntb->epf->vfunc_no, db_bar);
+	if (ret) {
+		dev_err(&epf->dev, "Failed to set Doorbell BAR\n");
+		goto err_free_irq;
+	}
+
+	for (i = 0; i < ntb->db_count; i++) {
+		struct msi_msg *msg = &epf->db_msg[i].msg;
+		dma_addr_t addr;
+		size_t offset;
+
+		ret = pci_epf_align_inbound_addr(epf, db_bar->barno,
+				((u64)msg->address_hi << 32) | msg->address_lo,
+				&addr, &offset);
+
+		if (ret) {
+			ntb->msi_doorbell = false;
+			goto err_free_irq;
+		}
+
+		ntb->reg->db_data[i] = msg->data;
+		ntb->reg->db_offset[i] = offset;
+	}
+
+	ntb->reg->db_entry_size = 0;
+
+	ntb->msi_doorbell = true;
+
+	return 0;
+
+err_free_irq:
+	for (i--; i >= 0; i--)
+		free_irq(epf->db_msg[i].virq, ntb);
+
+	pci_epf_free_doorbell(ntb->epf);
+	return ret;
+}
+
 /**
  * epf_ntb_db_bar_init() - Configure Doorbell window BARs
  * @ntb: NTB device that facilitates communication between HOST and VHOST
@@ -527,43 +614,36 @@ static int epf_ntb_configure_interrupt(struct epf_ntb *ntb)
 static int epf_ntb_db_bar_init(struct epf_ntb *ntb)
 {
 	const struct pci_epc_features *epc_features;
-	u32 align;
 	struct device *dev = &ntb->epf->dev;
 	int ret;
 	struct pci_epf_bar *epf_bar;
-	void __iomem *mw_addr;
+	void *mw_addr;
 	enum pci_barno barno;
 	size_t size = sizeof(u32) * ntb->db_count;
 
 	epc_features = pci_epc_get_features(ntb->epf->epc,
 					    ntb->epf->func_no,
 					    ntb->epf->vfunc_no);
-	align = epc_features->align;
-
-	if (size < 128)
-		size = 128;
-
-	if (align)
-		size = ALIGN(size, align);
-	else
-		size = roundup_pow_of_two(size);
-
 	barno = ntb->epf_ntb_bar[BAR_DB];
-
-	mw_addr = pci_epf_alloc_space(ntb->epf, size, barno, align, 0);
-	if (!mw_addr) {
-		dev_err(dev, "Failed to allocate OB address\n");
-		return -ENOMEM;
-	}
-
-	ntb->epf_db = mw_addr;
-
 	epf_bar = &ntb->epf->bar[barno];
 
-	ret = pci_epc_set_bar(ntb->epf->epc, ntb->epf->func_no, ntb->epf->vfunc_no, epf_bar);
+	ret = epf_ntb_db_bar_init_msi_doorbell(ntb, epf_bar, epc_features, barno);
 	if (ret) {
-		dev_err(dev, "Doorbell BAR set failed\n");
+		/* fall back to polling mode */
+		mw_addr = pci_epf_alloc_space(ntb->epf, size, barno, epc_features, 0);
+		if (!mw_addr) {
+			dev_err(dev, "Failed to allocate OB address\n");
+			return -ENOMEM;
+		}
+
+		ntb->epf_db = mw_addr;
+
+		ret = pci_epc_set_bar(ntb->epf->epc, ntb->epf->func_no,
+				      ntb->epf->vfunc_no, epf_bar);
+		if (ret) {
+			dev_err(dev, "Doorbell BAR set failed\n");
 			goto err_alloc_peer_mem;
+		}
 	}
 	return ret;
 
@@ -583,6 +663,16 @@ static void epf_ntb_db_bar_clear(struct epf_ntb *ntb)
 {
 	enum pci_barno barno;
 
+	if (ntb->msi_doorbell) {
+		int i;
+
+		for (i = 0; i < ntb->db_count; i++)
+			free_irq(ntb->epf->db_msg[i].virq, ntb);
+	}
+
+	if (ntb->epf->db_msg)
+		pci_epf_free_doorbell(ntb->epf);
+
 	barno = ntb->epf_ntb_bar[BAR_DB];
 	pci_epf_free_space(ntb->epf, ntb->epf_db, barno, 0);
 	pci_epc_clear_bar(ntb->epf->epc,
@@ -607,7 +697,7 @@ static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
 
 	for (i = 0; i < ntb->num_mws; i++) {
 		size = ntb->mws_size[i];
-		barno = ntb->epf_ntb_bar[BAR_MW0 + i];
+		barno = ntb->epf_ntb_bar[BAR_MW1 + i];
 
 		ntb->epf->bar[barno].barno = barno;
 		ntb->epf->bar[barno].size = size;
@@ -660,7 +750,7 @@ static void epf_ntb_mw_bar_clear(struct epf_ntb *ntb, int num_mws)
 	int i;
 
 	for (i = 0; i < num_mws; i++) {
-		barno = ntb->epf_ntb_bar[BAR_MW0 + i];
+		barno = ntb->epf_ntb_bar[BAR_MW1 + i];
 		pci_epc_clear_bar(ntb->epf->epc,
 				  ntb->epf->func_no,
 				  ntb->epf->vfunc_no,
@@ -685,6 +775,63 @@ static void epf_ntb_epc_destroy(struct epf_ntb *ntb)
 	pci_epc_put(ntb->epf->epc);
 }
 
+
+/**
+ * epf_ntb_is_bar_used() - Check if a bar is used in the ntb configuration
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
+ * @barno: Checked bar number
+ *
+ * Returns: true if used, false if free.
+ */
+static bool epf_ntb_is_bar_used(struct epf_ntb *ntb,
+				enum pci_barno barno)
+{
+	int i;
+
+	for (i = 0; i < VNTB_BAR_NUM; i++) {
+		if (ntb->epf_ntb_bar[i] == barno)
+			return true;
+	}
+
+	return false;
+}
+
+/**
+ * epf_ntb_find_bar() - Assign BAR number when no configuration is provided
+ * @ntb: NTB device that facilitates communication between HOST and VHOST
+ * @epc_features: The features provided by the EPC specific to this EPF
+ * @bar: NTB BAR index
+ * @barno: Bar start index
+ *
+ * When the BAR configuration was not provided through the userspace
+ * configuration, automatically assign BAR as it has been historically
+ * done by this endpoint function.
+ *
+ * Returns: the BAR number found, if any. -1 otherwise
+ */
+static int epf_ntb_find_bar(struct epf_ntb *ntb,
+			    const struct pci_epc_features *epc_features,
+			    enum epf_ntb_bar bar,
+			    enum pci_barno barno)
+{
+	while (ntb->epf_ntb_bar[bar] < 0) {
+		barno = pci_epc_get_next_free_bar(epc_features, barno);
+		if (barno < 0)
+			break; /* No more BAR available */
+
+		/*
+		 * Verify if the BAR found is not already assigned
+		 * through the provided configuration
+		 */
+		if (!epf_ntb_is_bar_used(ntb, barno))
+			ntb->epf_ntb_bar[bar] = barno;
+
+		barno += 1;
+	}
+
+	return barno;
+}
+
 /**
  * epf_ntb_init_epc_bar() - Identify BARs to be used for each of the NTB
  * constructs (scratchpad region, doorbell, memorywindow)
@@ -707,23 +854,21 @@ static int epf_ntb_init_epc_bar(struct epf_ntb *ntb)
 	epc_features = pci_epc_get_features(ntb->epf->epc, ntb->epf->func_no, ntb->epf->vfunc_no);
 
 	/* These are required BARs which are mandatory for NTB functionality */
-	for (bar = BAR_CONFIG; bar <= BAR_MW0; bar++, barno++) {
-		barno = pci_epc_get_next_free_bar(epc_features, barno);
+	for (bar = BAR_CONFIG; bar <= BAR_MW1; bar++) {
+		barno = epf_ntb_find_bar(ntb, epc_features, bar, barno);
 		if (barno < 0) {
 			dev_err(dev, "Fail to get NTB function BAR\n");
-			return barno;
+			return -ENOENT;
 		}
-		ntb->epf_ntb_bar[bar] = barno;
 	}
 
 	/* These are optional BARs which don't impact NTB functionality */
-	for (bar = BAR_MW1, i = 1; i < num_mws; bar++, barno++, i++) {
-		barno = pci_epc_get_next_free_bar(epc_features, barno);
+	for (bar = BAR_MW1, i = 1; i < num_mws; bar++, i++) {
+		barno = epf_ntb_find_bar(ntb, epc_features, bar, barno);
 		if (barno < 0) {
 			ntb->num_mws = i;
 			dev_dbg(dev, "BAR not available for > MW%d\n", i + 1);
 		}
-		ntb->epf_ntb_bar[bar] = barno;
 	}
 
 	return 0;
@@ -810,8 +955,9 @@ err_config_interrupt:
  */
 static void epf_ntb_epc_cleanup(struct epf_ntb *ntb)
 {
-	epf_ntb_db_bar_clear(ntb);
 	epf_ntb_mw_bar_clear(ntb, ntb->num_mws);
+	epf_ntb_db_bar_clear(ntb);
+	epf_ntb_config_sspad_bar_clear(ntb);
 }
 
 #define EPF_NTB_R(_name)						\
@@ -890,6 +1036,37 @@ static ssize_t epf_ntb_##_name##_store(struct config_item *item,	\
 	return len;							\
 }
 
+#define EPF_NTB_BAR_R(_name, _id)					\
+	static ssize_t epf_ntb_##_name##_show(struct config_item *item,	\
+					      char *page)		\
+	{								\
+		struct config_group *group = to_config_group(item);	\
+		struct epf_ntb *ntb = to_epf_ntb(group);		\
+									\
+		return sprintf(page, "%d\n", ntb->epf_ntb_bar[_id]);	\
+	}
+
+#define EPF_NTB_BAR_W(_name, _id)					\
+	static ssize_t epf_ntb_##_name##_store(struct config_item *item, \
+					       const char *page, size_t len) \
+	{								\
+		struct config_group *group = to_config_group(item);	\
+		struct epf_ntb *ntb = to_epf_ntb(group);		\
+		int val;						\
+		int ret;						\
+									\
+		ret = kstrtoint(page, 0, &val);				\
+		if (ret)						\
+			return ret;					\
+									\
+		if (val < NO_BAR || val > BAR_5)			\
+			return -EINVAL;					\
+									\
+		ntb->epf_ntb_bar[_id] = val;				\
+									\
+		return len;						\
+	}
+
 static ssize_t epf_ntb_num_mws_store(struct config_item *item,
 				     const char *page, size_t len)
 {
@@ -929,6 +1106,18 @@ EPF_NTB_MW_R(mw3)
 EPF_NTB_MW_W(mw3)
 EPF_NTB_MW_R(mw4)
 EPF_NTB_MW_W(mw4)
+EPF_NTB_BAR_R(ctrl_bar, BAR_CONFIG)
+EPF_NTB_BAR_W(ctrl_bar, BAR_CONFIG)
+EPF_NTB_BAR_R(db_bar, BAR_DB)
+EPF_NTB_BAR_W(db_bar, BAR_DB)
+EPF_NTB_BAR_R(mw1_bar, BAR_MW1)
+EPF_NTB_BAR_W(mw1_bar, BAR_MW1)
+EPF_NTB_BAR_R(mw2_bar, BAR_MW2)
+EPF_NTB_BAR_W(mw2_bar, BAR_MW2)
+EPF_NTB_BAR_R(mw3_bar, BAR_MW3)
+EPF_NTB_BAR_W(mw3_bar, BAR_MW3)
+EPF_NTB_BAR_R(mw4_bar, BAR_MW4)
+EPF_NTB_BAR_W(mw4_bar, BAR_MW4)
 
 CONFIGFS_ATTR(epf_ntb_, spad_count);
 CONFIGFS_ATTR(epf_ntb_, db_count);
@@ -940,6 +1129,12 @@ CONFIGFS_ATTR(epf_ntb_, mw4);
 CONFIGFS_ATTR(epf_ntb_, vbus_number);
 CONFIGFS_ATTR(epf_ntb_, vntb_pid);
 CONFIGFS_ATTR(epf_ntb_, vntb_vid);
+CONFIGFS_ATTR(epf_ntb_, ctrl_bar);
+CONFIGFS_ATTR(epf_ntb_, db_bar);
+CONFIGFS_ATTR(epf_ntb_, mw1_bar);
+CONFIGFS_ATTR(epf_ntb_, mw2_bar);
+CONFIGFS_ATTR(epf_ntb_, mw3_bar);
+CONFIGFS_ATTR(epf_ntb_, mw4_bar);
 
 static struct configfs_attribute *epf_ntb_attrs[] = {
 	&epf_ntb_attr_spad_count,
@@ -952,6 +1147,12 @@ static struct configfs_attribute *epf_ntb_attrs[] = {
 	&epf_ntb_attr_vbus_number,
 	&epf_ntb_attr_vntb_pid,
 	&epf_ntb_attr_vntb_vid,
+	&epf_ntb_attr_ctrl_bar,
+	&epf_ntb_attr_db_bar,
+	&epf_ntb_attr_mw1_bar,
+	&epf_ntb_attr_mw2_bar,
+	&epf_ntb_attr_mw3_bar,
+	&epf_ntb_attr_mw4_bar,
 	NULL,
 };
 
@@ -986,22 +1187,22 @@ static struct config_group *epf_ntb_add_cfs(struct pci_epf *epf,
 /*==== virtual PCI bus driver, which only load virtual NTB PCI driver ====*/
 
 static u32 pci_space[] = {
-	0xffffffff,	/*DeviceID, Vendor ID*/
-	0,		/*Status, Command*/
-	0xffffffff,	/*Class code, subclass, prog if, revision id*/
-	0x40,		/*bist, header type, latency Timer, cache line size*/
-	0,		/*BAR 0*/
-	0,		/*BAR 1*/
-	0,		/*BAR 2*/
-	0,		/*BAR 3*/
-	0,		/*BAR 4*/
-	0,		/*BAR 5*/
-	0,		/*Cardbus cis point*/
-	0,		/*Subsystem ID Subystem vendor id*/
-	0,		/*ROM Base Address*/
-	0,		/*Reserved, Cap. Point*/
-	0,		/*Reserved,*/
-	0,		/*Max Lat, Min Gnt, interrupt pin, interrupt line*/
+	0xffffffff,	/* Device ID, Vendor ID */
+	0,		/* Status, Command */
+	0xffffffff,	/* Base Class, Subclass, Prog Intf, Revision ID */
+	0x40,		/* BIST, Header Type, Latency Timer, Cache Line Size */
+	0,		/* BAR 0 */
+	0,		/* BAR 1 */
+	0,		/* BAR 2 */
+	0,		/* BAR 3 */
+	0,		/* BAR 4 */
+	0,		/* BAR 5 */
+	0,		/* Cardbus CIS Pointer */
+	0,		/* Subsystem ID, Subsystem Vendor ID */
+	0,		/* ROM Base Address */
+	0,		/* Reserved, Capabilities Pointer */
+	0,		/* Reserved */
+	0,		/* Max_Lat, Min_Gnt, Interrupt Pin, Interrupt Line */
 };
 
 static int pci_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *val)
@@ -1029,8 +1230,10 @@ static int vpci_scan_bus(void *sysdata)
 	struct epf_ntb *ndev = sysdata;
 
 	vpci_bus = pci_scan_bus(ndev->vbus_number, &vpci_ops, sysdata);
-	if (vpci_bus)
-		pr_err("create pci bus\n");
+	if (!vpci_bus) {
+		pr_err("create pci bus failed\n");
+		return -EINVAL;
+	}
 
 	pci_bus_add_devices(vpci_bus);
 
@@ -1076,7 +1279,7 @@ static int vntb_epf_mw_set_trans(struct ntb_dev *ndev, int pidx, int idx,
 	struct device *dev;
 
 	dev = &ntb->ntb.dev;
-	barno = ntb->epf_ntb_bar[BAR_MW0 + idx];
+	barno = ntb->epf_ntb_bar[BAR_MW1 + idx];
 	epf_bar = &ntb->epf->bar[barno];
 	epf_bar->phys_addr = addr;
 	epf_bar->barno = barno;
@@ -1172,11 +1375,8 @@ static int vntb_epf_peer_db_set(struct ntb_dev *ndev, u64 db_bits)
 	func_no = ntb->epf->func_no;
 	vfunc_no = ntb->epf->vfunc_no;
 
-	ret = pci_epc_raise_irq(ntb->epf->epc,
-				func_no,
-				vfunc_no,
-				PCI_EPC_IRQ_MSI,
-				interrupt_num + 1);
+	ret = pci_epc_raise_irq(ntb->epf->epc, func_no, vfunc_no,
+				PCI_IRQ_MSI, interrupt_num + 1);
 	if (ret)
 		dev_err(&ntb->ntb.dev, "Failed to raise IRQ\n");
 
@@ -1187,7 +1387,7 @@ static u64 vntb_epf_db_read(struct ntb_dev *ndev)
 {
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 
-	return ntb->db;
+	return atomic64_read(&ntb->db);
 }
 
 static int vntb_epf_mw_get_align(struct ntb_dev *ndev, int pidx, int idx,
@@ -1227,7 +1427,7 @@ static int vntb_epf_db_clear(struct ntb_dev *ndev, u64 db_bits)
 {
 	struct epf_ntb *ntb = ntb_ndev(ndev);
 
-	ntb->db &= ~db_bits;
+	atomic64_and(~db_bits, &ntb->db);
 	return 0;
 }
 
@@ -1272,21 +1472,17 @@ static int pci_vntb_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
 	if (ret) {
 		dev_err(dev, "Cannot set DMA mask\n");
-		return -EINVAL;
+		return ret;
 	}
 
 	ret = ntb_register_device(&ndev->ntb);
 	if (ret) {
 		dev_err(dev, "Failed to register NTB device\n");
-		goto err_register_dev;
+		return ret;
 	}
 
 	dev_dbg(dev, "PCI Virtual NTB driver loaded\n");
 	return 0;
-
-err_register_dev:
-	put_device(&ndev->ntb.dev);
-	return -EINVAL;
 }
 
 static struct pci_device_id pci_vntb_table[] = {
@@ -1353,13 +1549,19 @@ static int epf_ntb_bind(struct pci_epf *epf)
 	ret = pci_register_driver(&vntb_pci_driver);
 	if (ret) {
 		dev_err(dev, "failure register vntb pci driver\n");
-		goto err_bar_alloc;
+		goto err_epc_cleanup;
 	}
 
-	vpci_scan_bus(ntb);
+	ret = vpci_scan_bus(ntb);
+	if (ret)
+		goto err_unregister;
 
 	return 0;
 
+err_unregister:
+	pci_unregister_driver(&vntb_pci_driver);
+err_epc_cleanup:
+	epf_ntb_epc_cleanup(ntb);
 err_bar_alloc:
 	epf_ntb_config_spad_bar_free(ntb);
 
@@ -1387,7 +1589,7 @@ static void epf_ntb_unbind(struct pci_epf *epf)
 }
 
 // EPF driver probe
-static struct pci_epf_ops epf_ntb_ops = {
+static const struct pci_epf_ops epf_ntb_ops = {
 	.bind   = epf_ntb_bind,
 	.unbind = epf_ntb_unbind,
 	.add_cfs = epf_ntb_add_cfs,
@@ -1408,6 +1610,7 @@ static int epf_ntb_probe(struct pci_epf *epf,
 {
 	struct epf_ntb *ntb;
 	struct device *dev;
+	int i;
 
 	dev = &epf->dev;
 
@@ -1418,6 +1621,11 @@ static int epf_ntb_probe(struct pci_epf *epf,
 	epf->header = &epf_ntb_header;
 	ntb->epf = epf;
 	ntb->vbus_number = 0xff;
+
+	/* Initially, no bar is assigned */
+	for (i = 0; i < VNTB_BAR_NUM; i++)
+		ntb->epf_ntb_bar[i] = NO_BAR;
+
 	epf_set_drvdata(epf, ntb);
 
 	dev_info(dev, "pci-ep epf driver loaded\n");