VMCI: Support upto 64-bit PPNs

Add support in the VMCI driver to handle upto 64-bit PPNs when the VMCI
device exposes the capability for 64-bit PPNs.
Reviewed-by: Adit Ranadive <aditr@vmware.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Vishnu Dasa <vdasa@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/vmw_vmci/vmci_doorbell.c

@@ -330,7 +330,7 @@ int vmci_dbell_host_context_notify(u32 src_cid, struct vmci_handle handle)
 /*
  * Register the notification bitmap with the host.
  */
-bool vmci_dbell_register_notification_bitmap(u32 bitmap_ppn)
+bool vmci_dbell_register_notification_bitmap(u64 bitmap_ppn)
 {
 	int result;
 	struct vmci_notify_bm_set_msg bitmap_set_msg;
@@ -340,11 +340,14 @@ bool vmci_dbell_register_notification_bitmap(u32 bitmap_ppn)
 	bitmap_set_msg.hdr.src = VMCI_ANON_SRC_HANDLE;
 	bitmap_set_msg.hdr.payload_size = sizeof(bitmap_set_msg) -
 	    VMCI_DG_HEADERSIZE;
-	bitmap_set_msg.bitmap_ppn = bitmap_ppn;
+	if (vmci_use_ppn64())
+		bitmap_set_msg.bitmap_ppn64 = bitmap_ppn;
+	else
+		bitmap_set_msg.bitmap_ppn32 = (u32) bitmap_ppn;
 
 	result = vmci_send_datagram(&bitmap_set_msg.hdr);
 	if (result != VMCI_SUCCESS) {
-		pr_devel("Failed to register (PPN=%u) as notification bitmap (error=%d)\n",
+		pr_devel("Failed to register (PPN=%llu) as notification bitmap (error=%d)\n",
 			 bitmap_ppn, result);
 		return false;
 	}

drivers/misc/vmw_vmci/vmci_doorbell.h

@@ -45,7 +45,7 @@ struct dbell_cpt_state {
 int vmci_dbell_host_context_notify(u32 src_cid, struct vmci_handle handle);
 int vmci_dbell_get_priv_flags(struct vmci_handle handle, u32 *priv_flags);
 
-bool vmci_dbell_register_notification_bitmap(u32 bitmap_ppn);
+bool vmci_dbell_register_notification_bitmap(u64 bitmap_ppn);
 void vmci_dbell_scan_notification_entries(u8 *bitmap);
 
 #endif /* VMCI_DOORBELL_H */

drivers/misc/vmw_vmci/vmci_driver.h

@@ -54,4 +54,6 @@ void vmci_guest_exit(void);
 bool vmci_guest_code_active(void);
 u32 vmci_get_vm_context_id(void);
 
+bool vmci_use_ppn64(void);
+
 #endif /* _VMCI_DRIVER_H_ */

drivers/misc/vmw_vmci/vmci_guest.c

@@ -64,6 +64,13 @@ struct vmci_guest_device {
 	dma_addr_t notification_base;
 };
 
+static bool use_ppn64;
+
+bool vmci_use_ppn64(void)
+{
+	return use_ppn64;
+}
+
 /* vmci_dev singleton device and supporting data*/
 struct pci_dev *vmci_pdev;
 static struct vmci_guest_device *vmci_dev_g;
@@ -432,6 +439,7 @@ static int vmci_guest_probe_device(struct pci_dev *pdev,
 	struct vmci_guest_device *vmci_dev;
 	void __iomem *iobase;
 	unsigned int capabilities;
+	unsigned int caps_in_use;
 	unsigned long cmd;
 	int vmci_err;
 	int error;
@@ -496,6 +504,23 @@ static int vmci_guest_probe_device(struct pci_dev *pdev,
 		error = -ENXIO;
 		goto err_free_data_buffer;
 	}
+	caps_in_use = VMCI_CAPS_DATAGRAM;
+
+	/*
+	 * Use 64-bit PPNs if the device supports.
+	 *
+	 * There is no check for the return value of dma_set_mask_and_coherent
+	 * since this driver can handle the default mask values if
+	 * dma_set_mask_and_coherent fails.
+	 */
+	if (capabilities & VMCI_CAPS_PPN64) {
+		dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
+		use_ppn64 = true;
+		caps_in_use |= VMCI_CAPS_PPN64;
+	} else {
+		dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(44));
+		use_ppn64 = false;
+	}
 
 	/*
 	 * If the hardware supports notifications, we will use that as
@@ -510,14 +535,14 @@ static int vmci_guest_probe_device(struct pci_dev *pdev,
 				 "Unable to allocate notification bitmap\n");
 		} else {
 			memset(vmci_dev->notification_bitmap, 0, PAGE_SIZE);
-			capabilities |= VMCI_CAPS_NOTIFICATIONS;
+			caps_in_use |= VMCI_CAPS_NOTIFICATIONS;
 		}
 	}
 
-	dev_info(&pdev->dev, "Using capabilities 0x%x\n", capabilities);
+	dev_info(&pdev->dev, "Using capabilities 0x%x\n", caps_in_use);
 
 	/* Let the host know which capabilities we intend to use. */
-	iowrite32(capabilities, vmci_dev->iobase + VMCI_CAPS_ADDR);
+	iowrite32(caps_in_use, vmci_dev->iobase + VMCI_CAPS_ADDR);
 
 	/* Set up global device so that we can start sending datagrams */
 	spin_lock_irq(&vmci_dev_spinlock);
@@ -529,13 +554,13 @@ static int vmci_guest_probe_device(struct pci_dev *pdev,
 	 * Register notification bitmap with device if that capability is
 	 * used.
 	 */
-	if (capabilities & VMCI_CAPS_NOTIFICATIONS) {
+	if (caps_in_use & VMCI_CAPS_NOTIFICATIONS) {
 		unsigned long bitmap_ppn =
 			vmci_dev->notification_base >> PAGE_SHIFT;
 		if (!vmci_dbell_register_notification_bitmap(bitmap_ppn)) {
 			dev_warn(&pdev->dev,
-				 "VMCI device unable to register notification bitmap with PPN 0x%x\n",
-				 (u32) bitmap_ppn);
+				 "VMCI device unable to register notification bitmap with PPN 0x%lx\n",
+				 bitmap_ppn);
 			error = -ENXIO;
 			goto err_remove_vmci_dev_g;
 		}
@@ -611,7 +636,7 @@ static int vmci_guest_probe_device(struct pci_dev *pdev,
 
 	/* Enable specific interrupt bits. */
 	cmd = VMCI_IMR_DATAGRAM;
-	if (capabilities & VMCI_CAPS_NOTIFICATIONS)
+	if (caps_in_use & VMCI_CAPS_NOTIFICATIONS)
 		cmd |= VMCI_IMR_NOTIFICATION;
 	iowrite32(cmd, vmci_dev->iobase + VMCI_IMR_ADDR);
 

drivers/misc/vmw_vmci/vmci_queue_pair.c

@@ -435,8 +435,8 @@ static int qp_alloc_ppn_set(void *prod_q,
 			    void *cons_q,
 			    u64 num_consume_pages, struct ppn_set *ppn_set)
 {
-	u32 *produce_ppns;
-	u32 *consume_ppns;
+	u64 *produce_ppns;
+	u64 *consume_ppns;
 	struct vmci_queue *produce_q = prod_q;
 	struct vmci_queue *consume_q = cons_q;
 	u64 i;
@@ -462,31 +462,13 @@ static int qp_alloc_ppn_set(void *prod_q,
 		return VMCI_ERROR_NO_MEM;
 	}
 
-	for (i = 0; i < num_produce_pages; i++) {
-		unsigned long pfn;
-
+	for (i = 0; i < num_produce_pages; i++)
 		produce_ppns[i] =
 			produce_q->kernel_if->u.g.pas[i] >> PAGE_SHIFT;
-		pfn = produce_ppns[i];
-
-		/* Fail allocation if PFN isn't supported by hypervisor. */
-		if (sizeof(pfn) > sizeof(*produce_ppns)
-		    && pfn != produce_ppns[i])
-			goto ppn_error;
-	}
-
-	for (i = 0; i < num_consume_pages; i++) {
-		unsigned long pfn;
 
+	for (i = 0; i < num_consume_pages; i++)
 		consume_ppns[i] =
 			consume_q->kernel_if->u.g.pas[i] >> PAGE_SHIFT;
-		pfn = consume_ppns[i];
-
-		/* Fail allocation if PFN isn't supported by hypervisor. */
-		if (sizeof(pfn) > sizeof(*consume_ppns)
-		    && pfn != consume_ppns[i])
-			goto ppn_error;
-	}
 
 	ppn_set->num_produce_pages = num_produce_pages;
 	ppn_set->num_consume_pages = num_consume_pages;
@@ -494,11 +476,6 @@ static int qp_alloc_ppn_set(void *prod_q,
 	ppn_set->consume_ppns = consume_ppns;
 	ppn_set->initialized = true;
 	return VMCI_SUCCESS;
-
- ppn_error:
-	kfree(produce_ppns);
-	kfree(consume_ppns);
-	return VMCI_ERROR_INVALID_ARGS;
 }
 
 /*
@@ -520,12 +497,28 @@ static void qp_free_ppn_set(struct ppn_set *ppn_set)
  */
 static int qp_populate_ppn_set(u8 *call_buf, const struct ppn_set *ppn_set)
 {
+	if (vmci_use_ppn64()) {
 		memcpy(call_buf, ppn_set->produce_ppns,
-	       ppn_set->num_produce_pages * sizeof(*ppn_set->produce_ppns));
+		       ppn_set->num_produce_pages *
+		       sizeof(*ppn_set->produce_ppns));
 		memcpy(call_buf +
-	       ppn_set->num_produce_pages * sizeof(*ppn_set->produce_ppns),
+		       ppn_set->num_produce_pages *
+		       sizeof(*ppn_set->produce_ppns),
 		       ppn_set->consume_ppns,
-	       ppn_set->num_consume_pages * sizeof(*ppn_set->consume_ppns));
+		       ppn_set->num_consume_pages *
+		       sizeof(*ppn_set->consume_ppns));
+	} else {
+		int i;
+		u32 *ppns = (u32 *) call_buf;
+
+		for (i = 0; i < ppn_set->num_produce_pages; i++)
+			ppns[i] = (u32) ppn_set->produce_ppns[i];
+
+		ppns = &ppns[ppn_set->num_produce_pages];
+
+		for (i = 0; i < ppn_set->num_consume_pages; i++)
+			ppns[i] = (u32) ppn_set->consume_ppns[i];
+	}
 
 	return VMCI_SUCCESS;
 }
@@ -951,13 +944,15 @@ static int qp_alloc_hypercall(const struct qp_guest_endpoint *entry)
 {
 	struct vmci_qp_alloc_msg *alloc_msg;
 	size_t msg_size;
+	size_t ppn_size;
 	int result;
 
 	if (!entry || entry->num_ppns <= 2)
 		return VMCI_ERROR_INVALID_ARGS;
 
+	ppn_size = vmci_use_ppn64() ? sizeof(u64) : sizeof(u32);
 	msg_size = sizeof(*alloc_msg) +
-	    (size_t) entry->num_ppns * sizeof(u32);
+	    (size_t) entry->num_ppns * ppn_size;
 	alloc_msg = kmalloc(msg_size, GFP_KERNEL);
 	if (!alloc_msg)
 		return VMCI_ERROR_NO_MEM;

drivers/misc/vmw_vmci/vmci_queue_pair.h

@@ -28,8 +28,8 @@ typedef int (*vmci_event_release_cb) (void *client_data);
 struct ppn_set {
 	u64 num_produce_pages;
 	u64 num_consume_pages;
-	u32 *produce_ppns;
-	u32 *consume_ppns;
+	u64 *produce_ppns;
+	u64 *consume_ppns;
 	bool initialized;
 };
 

include/linux/vmw_vmci_defs.h

@@ -45,6 +45,7 @@
 #define VMCI_CAPS_GUESTCALL     0x2
 #define VMCI_CAPS_DATAGRAM      0x4
 #define VMCI_CAPS_NOTIFICATIONS 0x8
+#define VMCI_CAPS_PPN64         0x10
 
 /* Interrupt Cause register bits. */
 #define VMCI_ICR_DATAGRAM      0x1
@@ -569,8 +570,10 @@ struct vmci_resource_query_msg {
  */
 struct vmci_notify_bm_set_msg {
 	struct vmci_datagram hdr;
-	u32 bitmap_ppn;
-	u32 _pad;
+	union {
+		u32 bitmap_ppn32;
+		u64 bitmap_ppn64;
+	};
 };
 
 /*