Re: [RFC PATCH 04/16] PCI: Rip out pci_bus_add_devices() from pci_scan_root_bus()

[Yijing Wang <wangyijing@huawei.com>]

On 2014/11/18 22:34, Liviu Dudau wrote:
> On Mon, Nov 17, 2014 at 10:21:38AM +0000, Yijing Wang wrote:
>> Rip out pci_bus_add_devices() from pci_scan_root_bus()
>> for following reasons.
>> 1. pci_scan_root_bus() means we only do the scan, we should
>> not add pci busses.
>> 2. A lots of drviers which use pci_scan_root_bus() call
>> pci_bus_size_bridges(), pci_bus_assign_resources() after
>> pci_scan_root_bus(). But strictly speaking pci_bus_add_devices()
>> should be called after the resources assignment.
> 
> This looks like a nice cleanup! Can we split this patch out
> of the series and start the ball running on getting ACKs
> for it? You are touching a lot of drivers here, you probably
> don't want the whole series to wait on approvals for this.

OK, I will separately this one out of this series.

> 
> Best regards,
> Liviu
> 
>>
>> Signed-off-by: Yijing Wang <wangyijing@huawei.com>
>> ---
>>  arch/alpha/kernel/pci.c           |    1 +
>>  arch/alpha/kernel/sys_nautilus.c  |    1 +
>>  arch/frv/mb93090-mb00/pci-vdk.c   |    8 +++++---
>>  arch/ia64/sn/kernel/io_init.c     |    2 ++
>>  arch/m68k/coldfire/pci.c          |    1 +
>>  arch/microblaze/pci/pci-common.c  |    2 +-
>>  arch/mips/pci/pci.c               |    1 +
>>  arch/mn10300/unit-asb2305/pci.c   |    7 +++++--
>>  arch/s390/pci/pci.c               |    2 +-
>>  arch/sh/drivers/pci/pci.c         |    1 +
>>  arch/sparc/kernel/leon_pci.c      |    1 +
>>  arch/sparc/kernel/pcic.c          |    2 ++
>>  arch/tile/kernel/pci.c            |    3 ++-
>>  arch/tile/kernel/pci_gx.c         |    3 ++-
>>  arch/unicore32/kernel/pci.c       |    2 +-
>>  arch/x86/pci/common.c             |   10 ++++++----
>>  arch/xtensa/kernel/pci.c          |    1 +
>>  drivers/pci/host/pci-xgene.c      |    2 +-
>>  drivers/pci/hotplug/ibmphp_core.c |    6 ++++--
>>  drivers/pci/probe.c               |    1 -
>>  20 files changed, 39 insertions(+), 18 deletions(-)
>>
>> diff --git a/arch/alpha/kernel/pci.c b/arch/alpha/kernel/pci.c
>> index 076c35c..81251a5 100644
>> --- a/arch/alpha/kernel/pci.c
>> +++ b/arch/alpha/kernel/pci.c
>> @@ -349,6 +349,7 @@ common_init_pci(void)
>>
>>         pci_assign_unassigned_resources();
>>         pci_fixup_irqs(alpha_mv.pci_swizzle, alpha_mv.pci_map_irq);
>> +       pci_bus_add_devices(bus);
>>  }
>>
>>
>> diff --git a/arch/alpha/kernel/sys_nautilus.c b/arch/alpha/kernel/sys_nautilus.c
>> index 1047ab3..60fbd77 100644
>> --- a/arch/alpha/kernel/sys_nautilus.c
>> +++ b/arch/alpha/kernel/sys_nautilus.c
>> @@ -253,6 +253,7 @@ nautilus_init_pci(void)
>>            for the root bus, so just clear it. */
>>         bus->self = NULL;
>>         pci_fixup_irqs(alpha_mv.pci_swizzle, alpha_mv.pci_map_irq);
>> +       pci_bus_add_devices(bus);
>>  }
>>
>>  /*
>> diff --git a/arch/frv/mb93090-mb00/pci-vdk.c b/arch/frv/mb93090-mb00/pci-vdk.c
>> index efa5d65..85f87dc 100644
>> --- a/arch/frv/mb93090-mb00/pci-vdk.c
>> +++ b/arch/frv/mb93090-mb00/pci-vdk.c
>> @@ -316,6 +316,7 @@ void pcibios_fixup_bus(struct pci_bus *bus)
>>
>>  int __init pcibios_init(void)
>>  {
>> +       struct pci_bus *bus = NULL;
>>         struct pci_ops *dir = NULL;
>>         LIST_HEAD(resources);
>>
>> @@ -383,12 +384,13 @@ int __init pcibios_init(void)
>>         printk("PCI: Probing PCI hardware\n");
>>         pci_add_resource(&resources, &pci_ioport_resource);
>>         pci_add_resource(&resources, &pci_iomem_resource);
>> -       pci_scan_root_bus(NULL, 0, pci_root_ops, NULL, &resources);
>> -
>> +       bus = pci_scan_root_bus(NULL, 0, pci_root_ops, NULL, &resources);
>> +       if (!bus)
>> +               return -ENXIO;
>>         pcibios_irq_init();
>>         pcibios_fixup_irqs();
>>         pcibios_resource_survey();
>> -
>> +       pci_bus_add_devices(bus);
>>         return 0;
>>  }
>>
>> diff --git a/arch/ia64/sn/kernel/io_init.c b/arch/ia64/sn/kernel/io_init.c
>> index 0b5ce82..1be65eb 100644
>> --- a/arch/ia64/sn/kernel/io_init.c
>> +++ b/arch/ia64/sn/kernel/io_init.c
>> @@ -271,7 +271,9 @@ sn_pci_controller_fixup(int segment, int busnum, struct pci_bus *bus)
>>         if (bus = NULL) {
>>                 kfree(res);
>>                 kfree(controller);
>> +               return;
>>         }
>> +       pci_bus_add_devices(bus);
>>  }
>>
>>  /*
>> diff --git a/arch/m68k/coldfire/pci.c b/arch/m68k/coldfire/pci.c
>> index 4d242fb..840a431 100644
>> --- a/arch/m68k/coldfire/pci.c
>> +++ b/arch/m68k/coldfire/pci.c
>> @@ -319,6 +319,7 @@ static int __init mcf_pci_init(void)
>>         pci_fixup_irqs(pci_common_swizzle, mcf_pci_map_irq);
>>         pci_bus_size_bridges(rootbus);
>>         pci_bus_assign_resources(rootbus);
>> +       pci_bus_add_devices(rootbus);
>>         return 0;
>>  }
>>
>> diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c
>> index 9037914..9ca7e3f 100644
>> --- a/arch/microblaze/pci/pci-common.c
>> +++ b/arch/microblaze/pci/pci-common.c
>> @@ -1344,8 +1344,8 @@ static void pcibios_scan_phb(struct pci_controller *hose)
>>         }
>>         bus->busn_res.start = hose->first_busno;
>>         hose->bus = bus;
>> -
>>         hose->last_busno = bus->busn_res.end;
>> +       pci_bus_add_devices(bus);
>>  }
>>
>>  static int __init pcibios_init(void)
>> diff --git a/arch/mips/pci/pci.c b/arch/mips/pci/pci.c
>> index 1bf60b1..f083688 100644
>> --- a/arch/mips/pci/pci.c
>> +++ b/arch/mips/pci/pci.c
>> @@ -113,6 +113,7 @@ static void pcibios_scanbus(struct pci_controller *hose)
>>                 if (!pci_has_flag(PCI_PROBE_ONLY)) {
>>                         pci_bus_size_bridges(bus);
>>                         pci_bus_assign_resources(bus);
>> +                       pci_bus_add_devices(bus);
>>                 }
>>         }
>>  }
>> diff --git a/arch/mn10300/unit-asb2305/pci.c b/arch/mn10300/unit-asb2305/pci.c
>> index 6b4339f..011af54 100644
>> --- a/arch/mn10300/unit-asb2305/pci.c
>> +++ b/arch/mn10300/unit-asb2305/pci.c
>> @@ -345,6 +345,7 @@ void pcibios_fixup_bus(struct pci_bus *bus)
>>   */
>>  static int __init pcibios_init(void)
>>  {
>> +       struct pci_bus *bus;
>>         resource_size_t io_offset, mem_offset;
>>         LIST_HEAD(resources);
>>
>> @@ -376,11 +377,13 @@ static int __init pcibios_init(void)
>>
>>         pci_add_resource_offset(&resources, &pci_ioport_resource, io_offset);
>>         pci_add_resource_offset(&resources, &pci_iomem_resource, mem_offset);
>> -       pci_scan_root_bus(NULL, 0, &pci_direct_ampci, NULL, &resources);
>> -
>> +       bus = pci_scan_root_bus(NULL, 0, &pci_direct_ampci, NULL, &resources);
>> +       if (!bus)
>> +               return 0;
>>         pcibios_irq_init();
>>         pcibios_fixup_irqs();
>>         pcibios_resource_survey();
>> +       pci_bus_add_devices(bus);
>>         return 0;
>>  }
>>
>> diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
>> index 2fa7b14..016ea48 100644
>> --- a/arch/s390/pci/pci.c
>> +++ b/arch/s390/pci/pci.c
>> @@ -755,7 +755,7 @@ static int zpci_scan_bus(struct zpci_dev *zdev)
>>                 zpci_cleanup_bus_resources(zdev);
>>                 return -EIO;
>>         }
>> -
>> +       pci_bus_add_devices(zdev->bus);
>>         zdev->bus->max_bus_speed = zdev->max_bus_speed;
>>         return 0;
>>  }
>> diff --git a/arch/sh/drivers/pci/pci.c b/arch/sh/drivers/pci/pci.c
>> index 1bc09ee..efc1051 100644
>> --- a/arch/sh/drivers/pci/pci.c
>> +++ b/arch/sh/drivers/pci/pci.c
>> @@ -69,6 +69,7 @@ static void pcibios_scanbus(struct pci_channel *hose)
>>
>>                 pci_bus_size_bridges(bus);
>>                 pci_bus_assign_resources(bus);
>> +               pci_bus_add_devices(bus);
>>         } else {
>>                 pci_free_resource_list(&resources);
>>         }
>> diff --git a/arch/sparc/kernel/leon_pci.c b/arch/sparc/kernel/leon_pci.c
>> index 899b720..2971076 100644
>> --- a/arch/sparc/kernel/leon_pci.c
>> +++ b/arch/sparc/kernel/leon_pci.c
>> @@ -40,6 +40,7 @@ void leon_pci_init(struct platform_device *ofdev, struct leon_pci_info *info)
>>
>>                 /* Assign devices with resources */
>>                 pci_assign_unassigned_resources();
>> +               pci_bus_add_devices(root_bus);
>>         } else {
>>                 pci_free_resource_list(&resources);
>>         }
>> diff --git a/arch/sparc/kernel/pcic.c b/arch/sparc/kernel/pcic.c
>> index 64aafac..5457814 100644
>> --- a/arch/sparc/kernel/pcic.c
>> +++ b/arch/sparc/kernel/pcic.c
>> @@ -392,6 +392,8 @@ static void __init pcic_pbm_scan_bus(struct linux_pcic *pcic)
>>
>>         pbm->pci_bus = pci_scan_root_bus(NULL, pbm->pci_first_busno,
>>                         &pcic_ops, pbm, NULL);
>> +       if (pbm->pci_bus)
>> +               pci_bus_add_devices(pbm->pci_bus);
>>  #if 0 /* deadwood transplanted from sparc64 */
>>         pci_fill_in_pbm_cookies(pbm->pci_bus, pbm, pbm->prom_node);
>>         pci_record_assignments(pbm, pbm->pci_bus);
>> diff --git a/arch/tile/kernel/pci.c b/arch/tile/kernel/pci.c
>> index 1f80a88..268423e 100644
>> --- a/arch/tile/kernel/pci.c
>> +++ b/arch/tile/kernel/pci.c
>> @@ -326,7 +326,8 @@ int __init pcibios_init(void)
>>
>>         /* Configure the max_read_size and max_payload_size values. */
>>         fixup_read_and_payload_sizes();
>> -
>> +       if (bus)
>> +               pci_bus_add_devices(bus);
>>         /* Record the I/O resources in the PCI controller structure. */
>>         for (i = 0; i < TILE_NUM_PCIE; i++) {
>>                 /*
>> diff --git a/arch/tile/kernel/pci_gx.c b/arch/tile/kernel/pci_gx.c
>> index e39f9c5..5f05a9a 100644
>> --- a/arch/tile/kernel/pci_gx.c
>> +++ b/arch/tile/kernel/pci_gx.c
>> @@ -903,7 +903,8 @@ int __init pcibios_init(void)
>>          * associated with the devices read in above.
>>          */
>>         pci_assign_unassigned_resources();
>> -
>> +       if (bus)
>> +               pci_bus_add_devices(bus);
>>         /* Record the I/O resources in the PCI controller structure. */
>>         for (i = 0; i < num_rc_controllers; i++) {
>>                 struct pci_controller *controller = &pci_controllers[i];
>> diff --git a/arch/unicore32/kernel/pci.c b/arch/unicore32/kernel/pci.c
>> index be0f261..0d4c563 100644
>> --- a/arch/unicore32/kernel/pci.c
>> +++ b/arch/unicore32/kernel/pci.c
>> @@ -270,11 +270,11 @@ static int __init pci_common_init(void)
>>                  * Size the bridge windows.
>>                  */
>>                 pci_bus_size_bridges(puv3_bus);
>> -
>>                 /*
>>                  * Assign resources.
>>                  */
>>                 pci_bus_assign_resources(puv3_bus);
>> +               pci_bus_add_devices(puv3_bus);
>>         }
>>
>>         return 0;
>> diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
>> index 7b20bcc..b16632b 100644
>> --- a/arch/x86/pci/common.c
>> +++ b/arch/x86/pci/common.c
>> @@ -471,10 +471,12 @@ void pcibios_scan_root(int 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);
>> -       }
>> +       if (bus) {
>> +               pci_bus_add_devices(bus);
>> +               return;
>> +       }
>> +       pci_free_resource_list(&resources);
>> +       kfree(sd);
>>  }
>>
>>  void __init pcibios_set_cache_line_size(void)
>> diff --git a/arch/xtensa/kernel/pci.c b/arch/xtensa/kernel/pci.c
>> index 5b34033..c4b5b5d 100644
>> --- a/arch/xtensa/kernel/pci.c
>> +++ b/arch/xtensa/kernel/pci.c
>> @@ -185,6 +185,7 @@ static int __init pcibios_init(void)
>>                 pci_controller_apertures(pci_ctrl, &resources);
>>                 bus = pci_scan_root_bus(NULL, pci_ctrl->first_busno,
>>                                         pci_ctrl->ops, pci_ctrl, &resources);
>> +               pci_bus_add_devices(bus);
>>                 pci_ctrl->bus = bus;
>>                 pci_ctrl->last_busno = bus->busn_res.end;
>>                 if (next_busno <= pci_ctrl->last_busno)
>> diff --git a/drivers/pci/host/pci-xgene.c b/drivers/pci/host/pci-xgene.c
>> index 9ecabfa..e7a4f66 100644
>> --- a/drivers/pci/host/pci-xgene.c
>> +++ b/drivers/pci/host/pci-xgene.c
>> @@ -634,7 +634,7 @@ static int xgene_pcie_probe_bridge(struct platform_device *pdev)
>>         bus = pci_scan_root_bus(&pdev->dev, 0, &xgene_pcie_ops, port, &res);
>>         if (!bus)
>>                 return -ENOMEM;
>> -
>> +       pci_bus_add_devices(bus);
>>         platform_set_drvdata(pdev, port);
>>         return 0;
>>  }
>> diff --git a/drivers/pci/hotplug/ibmphp_core.c b/drivers/pci/hotplug/ibmphp_core.c
>> index b486432..76ce157 100644
>> --- a/drivers/pci/hotplug/ibmphp_core.c
>> +++ b/drivers/pci/hotplug/ibmphp_core.c
>> @@ -740,7 +740,7 @@ static void ibm_unconfigure_device(struct pci_func *func)
>>   */
>>  static u8 bus_structure_fixup(u8 busno)
>>  {
>> -       struct pci_bus *bus;
>> +       struct pci_bus *bus, *b;
>>         struct pci_dev *dev;
>>         u16 l;
>>
>> @@ -767,7 +767,9 @@ static u8 bus_structure_fixup(u8 busno)
>>                                         (l != 0x0000) && (l != 0xffff)) {
>>                         debug("%s - Inside bus_structure_fixup()\n",
>>                                                         __func__);
>> -                       pci_scan_root_bus(NULL, busno, ibmphp_pci_bus->ops, NULL, NULL);
>> +                       b = pci_scan_root_bus(NULL, busno, ibmphp_pci_bus->ops, NULL, NULL);
>> +                       if (b)
>> +                               pci_bus_add_devices(b);
>>                         break;
>>                 }
>>         }
>> diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
>> index 0a02fc2..97711f3 100644
>> --- a/drivers/pci/probe.c
>> +++ b/drivers/pci/probe.c
>> @@ -2101,7 +2101,6 @@ struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
>>         if (!found)
>>                 pci_bus_update_busn_res_end(b, max);
>>
>> -       pci_bus_add_devices(b);
>>         return b;
>>  }
>>  EXPORT_SYMBOL(pci_scan_root_bus);
>> --
>> 1.7.1
>>
>> --
>> 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
>>
> 


-- 
Thanks!
Yijing