git: e7c58fc886ec - stable/13 - LinuxKPI: implement pci_rescan_bus()

The branch stable/13 has been updated by bz:

URL: https://cgit.FreeBSD.org/src/commit/?id=e7c58fc886ec09fe16bb544a2a3b2e9fcfbc0008

commit e7c58fc886ec09fe16bb544a2a3b2e9fcfbc0008
Author:     Bjoern A. Zeeb <bz@FreeBSD.org>
AuthorDate: 2023-05-16 20:59:30 +0000
Commit:     Bjoern A. Zeeb <bz@FreeBSD.org>
CommitDate: 2023-06-26 09:19:42 +0000

    LinuxKPI: implement pci_rescan_bus()
    
    Try to implement pci_rescan_bus().  pci_rescan_method() is already
    doing most of the job.  We only have to do the count for the return
    value again ourselves.
    
    Sponsored by:   The FreeBSD Foundation
    Reviewed by:    jhb
    Differential Revision: https://reviews.freebsd.org/D40122
    
    (cherry picked from commit 525dd4acaacc59b815131caccfdebc905d4d7bff)
---
 sys/compat/linuxkpi/common/include/linux/pci.h | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/sys/compat/linuxkpi/common/include/linux/pci.h b/sys/compat/linuxkpi/common/include/linux/pci.h
index 55435f6b72bc..f3c495ff1a21 100644
--- a/sys/compat/linuxkpi/common/include/linux/pci.h
+++ b/sys/compat/linuxkpi/common/include/linux/pci.h
@@ -277,6 +277,7 @@ _Static_assert(sizeof(struct pci_driver) == __PCI_DRIVER_SIZE,
 
 struct pci_bus {
 	struct pci_dev	*self;
+	/* struct pci_bus	*parent */
 	int		domain;
 	int		number;
 };
@@ -1425,6 +1426,29 @@ pci_stop_and_remove_bus_device(struct pci_dev *pdev)
 {
 }
 
+static inline int
+pci_rescan_bus(struct pci_bus *pbus)
+{
+	device_t *devlist, parent;
+	int devcount, error;
+
+	if (!device_is_attached(pbus->self->dev.bsddev))
+		return (0);
+	/* pci_rescan_method() will work on the pcib (parent). */
+	error = BUS_RESCAN(pbus->self->dev.bsddev);
+	if (error != 0)
+		return (0);
+
+	parent = device_get_parent(pbus->self->dev.bsddev);
+	error = device_get_children(parent, &devlist, &devcount);
+	if (error != 0)
+		return (0);
+	if (devcount != 0)
+		free(devlist, M_TEMP);
+
+	return (devcount);
+}
+
 /*
  * The following functions can be used to attach/detach the LinuxKPI's
  * PCI device runtime. The pci_driver and pci_device_id pointer is