Re: [RFC 08/15] x86: PCI: clean up pcibios_scan_root()
From: "Rafael J. Wysocki" <rafael@kernel.org>
Date: 2018-08-20 08:31:52
Also in:
linux-acpi, linux-pci, lkml
On Fri, Aug 17, 2018 at 12:32 PM Arnd Bergmann [off-list ref] wrote:
quoted hunk ↗ jump to hunk
pcibios_scan_root() is now just a wrapper around pci_scan_root_bus(), and merging the two into one makes it shorter and more readable. We can also take advantage of pci_alloc_host_bridge() doing the allocation of the sysdata for us, which helps if we ever want to allow hot-unplugging the host bridge itself. We might be able to simplify it further using pci_host_probe(), but I wasn't sure about the resource registration there. Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- arch/x86/pci/common.c | 53 ++++++++++++++----------------------------- 1 file changed, 17 insertions(+), 36 deletions(-)diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c index e740d9aa4024..920d0885434c 100644 --- a/arch/x86/pci/common.c +++ b/arch/x86/pci/common.c@@ -453,54 +453,35 @@ void __init dmi_check_pciprobe(void) dmi_check_system(pciprobe_dmi_table); } -static struct pci_bus *pci_scan_root_bus(struct device *parent, int bus, - struct pci_ops *ops, void *sysdata, struct list_head *resources) +void pcibios_scan_root(int busnum) { + struct pci_sysdata *sd; struct pci_host_bridge *bridge; int error; - bridge = pci_alloc_host_bridge(0); - if (!bridge) - return NULL; + bridge = pci_alloc_host_bridge(sizeof(sd)); + if (!bridge) { + printk(KERN_ERR "PCI: OOM, skipping PCI bus %02x\n", busnum); + return; + } + sd = pci_host_bridge_priv(bridge);
This looks fishy, as bridge->private is not set at this point AFAICS, unless one of the previous patches changes that.
- list_splice_init(resources, &bridge->windows);
- bridge->dev.parent = parent;
- bridge->sysdata = sysdata;
- bridge->busnr = bus;
- bridge->ops = ops;
+ sd->node = x86_pci_root_bus_node(busnum);
+ x86_pci_root_bus_resources(busnum, &bridge->windows);
+ bridge->sysdata = sd;
+ bridge->busnr = busnum;
+ bridge->ops = &pci_root_ops;
+ printk(KERN_DEBUG "PCI: Probing PCI hardware (bus %02x)\n", busnum);
error = pci_scan_root_bus_bridge(bridge);
if (error < 0)
goto err_out;
- return bridge->bus;
+ pci_bus_add_devices(bridge->bus);
+ return;
err_out:
- kfree(bridge);
- return NULL;
-}
-
-void pcibios_scan_root(int busnum)
-{
- struct pci_bus *bus;
- struct pci_sysdata *sd;
- LIST_HEAD(resources);
-
- sd = kzalloc(sizeof(*sd), GFP_KERNEL);
- if (!sd) {
- printk(KERN_ERR "PCI: OOM, skipping PCI bus %02x\n", busnum);
- return;
- }
- sd->node = x86_pci_root_bus_node(busnum);
- x86_pci_root_bus_resources(busnum, &resources);
- printk(KERN_DEBUG "PCI: Probing PCI hardware (bus %02x)\n", busnum);
- bus = pci_scan_root_bus(NULL, busnum, &pci_root_ops, sd, &resources);
- if (!bus) {
- pci_free_resource_list(&resources);
- kfree(sd);
- return;
- }
- pci_bus_add_devices(bus);
+ pci_free_host_bridge(bridge);
}
void __init pcibios_set_cache_line_size(void)
--
2.18.0