[PATCH v3 11/30] s390/pci: add helper function to find device by handle

[Matthew Rosato <mjrosato@linux.ibm.com>]

Intercepted zPCI instructions will specify the desired function via a
function handle.  Add a routine to find the device with the specified
handle.

Acked-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
---
 arch/s390/include/asm/pci.h |  1 +
 arch/s390/pci/pci.c         | 16 ++++++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/arch/s390/include/asm/pci.h b/arch/s390/include/asm/pci.h
index 7ee52a70a96f..3c0b9986dcdc 100644
--- a/arch/s390/include/asm/pci.h
+++ b/arch/s390/include/asm/pci.h
@@ -275,6 +275,7 @@ static inline struct zpci_dev *to_zpci_dev(struct device *dev)
 }
 
 struct zpci_dev *get_zdev_by_fid(u32);
+struct zpci_dev *get_zdev_by_fh(u32 fh);
 
 /* DMA */
 int zpci_dma_init(void);
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index ca9c29386de6..04c16312ad54 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -76,6 +76,22 @@ struct zpci_dev *get_zdev_by_fid(u32 fid)
 	return zdev;
 }
 
+struct zpci_dev *get_zdev_by_fh(u32 fh)
+{
+	struct zpci_dev *tmp, *zdev = NULL;
+
+	spin_lock(&zpci_list_lock);
+	list_for_each_entry(tmp, &zpci_list, entry) {
+		if (tmp->fh == fh) {
+			zdev = tmp;
+			break;
+		}
+	}
+	spin_unlock(&zpci_list_lock);
+	return zdev;
+}
+EXPORT_SYMBOL_GPL(get_zdev_by_fh);
+
 void zpci_remove_reserved_devices(void)
 {
 	struct zpci_dev *tmp, *zdev;
-- 
2.27.0