devres: implement pcim_iomap_regions_request_all()

Some drivers need to reserve all PCI BARs to prevent other drivers
misusing unoccupied BARs.  pcim_iomap_regions_request_all() requests
all BARs and iomap specified BARs.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

include/linux/pci.h

@@ -1045,6 +1045,8 @@ void __iomem *pcim_iomap(struct pci_dev *pdev, int bar, unsigned long maxlen);
 void pcim_iounmap(struct pci_dev *pdev, void __iomem *addr);
 void __iomem * const *pcim_iomap_table(struct pci_dev *pdev);
 int pcim_iomap_regions(struct pci_dev *pdev, u16 mask, const char *name);
+int pcim_iomap_regions_request_all(struct pci_dev *pdev, u16 mask,
+				   const char *name);
 void pcim_iounmap_regions(struct pci_dev *pdev, u16 mask);
 
 extern int pci_pci_problems;

lib/devres.c

@@ -297,6 +297,31 @@ int pcim_iomap_regions(struct pci_dev *pdev, u16 mask, const char *name)
 }
 EXPORT_SYMBOL(pcim_iomap_regions);
 
+/**
+ * pcim_iomap_regions_request_all - Request all BARs and iomap specified ones
+ * @pdev: PCI device to map IO resources for
+ * @mask: Mask of BARs to iomap
+ * @name: Name used when requesting regions
+ *
+ * Request all PCI BARs and iomap regions specified by @mask.
+ */
+int pcim_iomap_regions_request_all(struct pci_dev *pdev, u16 mask,
+				   const char *name)
+{
+	int request_mask = ((1 << 6) - 1) & ~mask;
+	int rc;
+
+	rc = pci_request_selected_regions(pdev, request_mask, name);
+	if (rc)
+		return rc;
+
+	rc = pcim_iomap_regions(pdev, mask, name);
+	if (rc)
+		pci_release_selected_regions(pdev, request_mask);
+	return rc;
+}
+EXPORT_SYMBOL(pcim_iomap_regions_request_all);
+
 /**
  * pcim_iounmap_regions - Unmap and release PCI BARs
  * @pdev: PCI device to map IO resources for