| Message ID | 1368550322-1045-9-git-send-email-jiang.liu@huawei.com |
|---|---|
| State | Superseded |
| Headers | show |
On Wed, 2013-05-15 at 00:51 +0800, Jiang Liu wrote: > Enhance PPC architecture specific code to use hotplug-safe iterators > to walk PCI buses. I was about to ack it but then I saw: > diff --git a/arch/powerpc/kernel/pci_64.c b/arch/powerpc/kernel/pci_64.c > index 51a133a..a41c6dd 100644 > --- a/arch/powerpc/kernel/pci_64.c > +++ b/arch/powerpc/kernel/pci_64.c > @@ -208,7 +208,6 @@ long sys_pciconfig_iobase(long which, unsigned long in_bus, > unsigned long in_devfn) > { > struct pci_controller* hose; > - struct list_head *ln; > struct pci_bus *bus = NULL; > struct device_node *hose_node; > > @@ -229,18 +228,16 @@ long sys_pciconfig_iobase(long which, unsigned long in_bus, > /* That syscall isn't quite compatible with PCI domains, but it's > * used on pre-domains setup. We return the first match > */ > - > - for (ln = pci_root_buses.next; ln != &pci_root_buses; ln = ln->next) { > - bus = pci_bus_b(ln); > - if (in_bus >= bus->number && in_bus <= bus->busn_res.end) > + for_each_pci_root_bus(bus) > + if (in_bus >= bus->number && in_bus <= bus->busn_res.end && > + bus->dev.of_node) > break; > - bus = NULL; > - } > - if (bus == NULL || bus->dev.of_node == NULL) > + if (bus == NULL) > return -ENODEV; You just removed the NULL check for the of_node field... > hose_node = bus->dev.of_node; > hose = PCI_DN(hose_node)->phb; Which is dereferrenced here. > + pci_bus_put(bus); On the other hand, the whole thing can probably be using pci_bus_to_host() instead.... the above code is bitrotted. > switch (which) { > case IOBASE_BRIDGE_NUMBER: Cheeers, Ben. -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 05/15/2013 07:30 AM, Benjamin Herrenschmidt wrote: > On Wed, 2013-05-15 at 00:51 +0800, Jiang Liu wrote: >> Enhance PPC architecture specific code to use hotplug-safe iterators >> to walk PCI buses. > I was about to ack it but then I saw: > >> diff --git a/arch/powerpc/kernel/pci_64.c b/arch/powerpc/kernel/pci_64.c >> index 51a133a..a41c6dd 100644 >> --- a/arch/powerpc/kernel/pci_64.c >> +++ b/arch/powerpc/kernel/pci_64.c >> @@ -208,7 +208,6 @@ long sys_pciconfig_iobase(long which, unsigned long in_bus, >> unsigned long in_devfn) >> { >> struct pci_controller* hose; >> - struct list_head *ln; >> struct pci_bus *bus = NULL; >> struct device_node *hose_node; >> >> @@ -229,18 +228,16 @@ long sys_pciconfig_iobase(long which, unsigned long in_bus, >> /* That syscall isn't quite compatible with PCI domains, but it's >> * used on pre-domains setup. We return the first match >> */ >> - >> - for (ln = pci_root_buses.next; ln != &pci_root_buses; ln = ln->next) { >> - bus = pci_bus_b(ln); >> - if (in_bus >= bus->number && in_bus <= bus->busn_res.end) >> + for_each_pci_root_bus(bus) >> + if (in_bus >= bus->number && in_bus <= bus->busn_res.end && >> + bus->dev.of_node) >> break; >> - bus = NULL; >> - } >> - if (bus == NULL || bus->dev.of_node == NULL) >> + if (bus == NULL) >> return -ENODEV; > You just removed the NULL check for the of_node field... Hi Benjamin, Thanks for review. I just moved the "bus->dev.of_node == NULL" into the above for_each_pci_root_bus() loop:) Will send you another version according to your suggestion to use pci_bus_to_host() to simplify the code. Regards! Gerry > >> hose_node = bus->dev.of_node; >> hose = PCI_DN(hose_node)->phb; > Which is dereferrenced here. > >> + pci_bus_put(bus); > On the other hand, the whole thing can probably be using > pci_bus_to_host() instead.... the above code is bitrotted. > >> switch (which) { >> case IOBASE_BRIDGE_NUMBER: > > Cheeers, > Ben. > > -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index fa12ae4..26fca09 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -1400,7 +1400,7 @@ void __init pcibios_resource_survey(void) struct pci_bus *b; /* Allocate and assign resources */ - list_for_each_entry(b, &pci_root_buses, node) + for_each_pci_root_bus(b) pcibios_allocate_bus_resources(b); pcibios_allocate_resources(0); pcibios_allocate_resources(1); @@ -1410,7 +1410,7 @@ void __init pcibios_resource_survey(void) * bus available resources to avoid allocating things on top of them */ if (!pci_has_flag(PCI_PROBE_ONLY)) { - list_for_each_entry(b, &pci_root_buses, node) + for_each_pci_root_bus(b) pcibios_reserve_legacy_regions(b); } diff --git a/arch/powerpc/kernel/pci_64.c b/arch/powerpc/kernel/pci_64.c index 51a133a..a41c6dd 100644 --- a/arch/powerpc/kernel/pci_64.c +++ b/arch/powerpc/kernel/pci_64.c @@ -208,7 +208,6 @@ long sys_pciconfig_iobase(long which, unsigned long in_bus, unsigned long in_devfn) { struct pci_controller* hose; - struct list_head *ln; struct pci_bus *bus = NULL; struct device_node *hose_node; @@ -229,18 +228,16 @@ long sys_pciconfig_iobase(long which, unsigned long in_bus, /* That syscall isn't quite compatible with PCI domains, but it's * used on pre-domains setup. We return the first match */ - - for (ln = pci_root_buses.next; ln != &pci_root_buses; ln = ln->next) { - bus = pci_bus_b(ln); - if (in_bus >= bus->number && in_bus <= bus->busn_res.end) + for_each_pci_root_bus(bus) + if (in_bus >= bus->number && in_bus <= bus->busn_res.end && + bus->dev.of_node) break; - bus = NULL; - } - if (bus == NULL || bus->dev.of_node == NULL) + if (bus == NULL) return -ENODEV; hose_node = bus->dev.of_node; hose = PCI_DN(hose_node)->phb; + pci_bus_put(bus); switch (which) { case IOBASE_BRIDGE_NUMBER:
Enhance PPC architecture specific code to use hotplug-safe iterators to walk PCI buses. Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Bjorn Helgaas <bhelgaas@google.com> Cc: Gavin Shan <shangw@linux.vnet.ibm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Bill Pemberton <wfp5p@virginia.edu> Cc: Yinghai Lu <yinghai@kernel.org> Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-kernel@vger.kernel.org --- arch/powerpc/kernel/pci-common.c | 4 ++-- arch/powerpc/kernel/pci_64.c | 13 +++++-------- 2 files changed, 7 insertions(+), 10 deletions(-)