[PATCH V4 6/9] PCI: hv: Export hv_build_devid_type_pci() and change return type

[Mukesh R <mrathor@linux.microsoft.com>]

On Hyper-V, most hypercalls related to PCI passthru to map/unmap regions,
interrupts, etc need a device ID as a parameter. This device ID refers
to that specific device during the lifetime of passthru. So,
make hv_build_devid_type_pci() public and change return type to u64 to
enforce it's size.

Signed-off-by: Mukesh R <mrathor@linux.microsoft.com>
Reviewed-by: Souradeep Chakrabarti <schakrabarti@linux.microsoft.com>
---
 arch/x86/hyperv/irqdomain.c     | 9 +++++----
 arch/x86/include/asm/mshyperv.h | 6 ++++++
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/arch/x86/hyperv/irqdomain.c b/arch/x86/hyperv/irqdomain.c
index b3ad50a874dc..8780573a4332 100644
--- a/arch/x86/hyperv/irqdomain.c
+++ b/arch/x86/hyperv/irqdomain.c
@@ -112,7 +112,7 @@ static int get_rid_cb(struct pci_dev *pdev, u16 alias, void *data)
 	return 0;
 }
 
-static union hv_device_id hv_build_devid_type_pci(struct pci_dev *pdev)
+u64 hv_build_devid_type_pci(struct pci_dev *pdev)
 {
 	int pos;
 	union hv_device_id hv_devid;
@@ -172,8 +172,9 @@ static union hv_device_id hv_build_devid_type_pci(struct pci_dev *pdev)
 	}
 
 out:
-	return hv_devid;
+	return hv_devid.as_uint64;
 }
+EXPORT_SYMBOL_GPL(hv_build_devid_type_pci);
 
 /*
  * hv_map_msi_interrupt() - Map the MSI IRQ in the hypervisor.
@@ -196,7 +197,7 @@ int hv_map_msi_interrupt(struct irq_data *data,
 
 	msidesc = irq_data_get_msi_desc(data);
 	pdev = msi_desc_to_pci_dev(msidesc);
-	hv_devid = hv_build_devid_type_pci(pdev);
+	hv_devid.as_uint64 = hv_build_devid_type_pci(pdev);
 	cpu = cpumask_first(irq_data_get_effective_affinity_mask(data));
 
 	return hv_map_interrupt(hv_devid, false, cpu, cfg->vector,
@@ -271,7 +272,7 @@ static int hv_unmap_msi_interrupt(struct pci_dev *pdev,
 {
 	union hv_device_id hv_devid;
 
-	hv_devid = hv_build_devid_type_pci(pdev);
+	hv_devid.as_uint64 = hv_build_devid_type_pci(pdev);
 	return hv_unmap_interrupt(hv_devid.as_uint64, irq_entry);
 }
 
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index f64393e853ee..8ebbd1cb7c8c 100644
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -248,6 +248,12 @@ void hv_crash_asm_end(void);
 static inline void hv_root_crash_init(void) {}
 #endif  /* CONFIG_MSHV_ROOT && CONFIG_CRASH_DUMP */
 
+#ifdef CONFIG_PCI_MSI
+u64 hv_build_devid_type_pci(struct pci_dev *pdev);
+#else
+static inline u64 hv_build_devid_type_pci(struct pci_dev *pdev) { return 0; }
+#endif
+
 #else /* CONFIG_HYPERV */
 static inline void hyperv_init(void) {}
 static inline void hyperv_setup_mmu_ops(void) {}
-- 
2.51.2.vfs.0.1