Patchwork [1/5] PCI/IA64: simplify code by hotplug safe pci_get_domain_bus_and_slot()

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Submitter Jiang Liu
Date Aug. 28, 2012, 3:43 p.m.
Message ID <1346168638-32724-2-git-send-email-jiang.liu@huawei.com>
Download mbox | patch
Permalink /patch/180515/
State Accepted
Headers show

Comments

Jiang Liu - Aug. 28, 2012, 3:43 p.m.
Following code has a race window between pci_find_bus() and pci_get_slot()
if PCI hotplug operation happens between them which removes the pci_bus.
So use PCI hotplug safe interface pci_get_domain_bus_and_slot() instead,
which also reduces code complexity.

struct pci_bus *pci_bus = pci_find_bus(domain, busno);
struct pci_dev *pci_dev = pci_get_slot(pci_bus, devfn);

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
---
 arch/ia64/sn/kernel/io_common.c |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

Patch

diff --git a/arch/ia64/sn/kernel/io_common.c b/arch/ia64/sn/kernel/io_common.c
index fbb5f2f..8630875 100644
--- a/arch/ia64/sn/kernel/io_common.c
+++ b/arch/ia64/sn/kernel/io_common.c
@@ -229,7 +229,6 @@  void sn_pci_fixup_slot(struct pci_dev *dev, struct pcidev_info *pcidev_info,
 {
 	int segment = pci_domain_nr(dev->bus);
 	struct pcibus_bussoft *bs;
-	struct pci_bus *host_pci_bus;
 	struct pci_dev *host_pci_dev;
 	unsigned int bus_no, devfn;
 
@@ -245,8 +244,7 @@  void sn_pci_fixup_slot(struct pci_dev *dev, struct pcidev_info *pcidev_info,
 
 	bus_no = (pcidev_info->pdi_slot_host_handle >> 32) & 0xff;
 	devfn = pcidev_info->pdi_slot_host_handle & 0xffffffff;
- 	host_pci_bus = pci_find_bus(segment, bus_no);
- 	host_pci_dev = pci_get_slot(host_pci_bus, devfn);
+	host_pci_dev = pci_get_domain_bus_and_slot(segment, bus_no, devfn);
 
 	pcidev_info->host_pci_dev = host_pci_dev;
 	pcidev_info->pdi_linux_pcidev = dev;