Re: [RFC PATCH 02/16] PCI: Use pci_scan_root_bus() instead of pci_scan_bus()

Liviu Dudau
2014-11-18T14:28:17Z

On Mon, Nov 17, 2014 at 10:21:36AM +0000, Yijing Wang wrote:
> From: Yijing Wang <wangyijing0307@gmail.com>
>
> Now we could use pci_scan_root_bus() instead of
> pci_scan_bus(), pass NULL resources means use the default
> io/mem.

Actually, I think this patch goes in the wrong direction. You are adding
two additional parameters that are NULL for every call you replace.
pci_scan_bus() was actually intended as a "shortcut with defaults" kind
of call so that you don't have to pass a value for parameters you don't
care about.

My suggestion would be to keep the function as is and replace the call
to pci_create_root_bus() inside with the appropriate sequence.

Best regards,
Liviu

>
> Signed-off-by: Yijing Wang <wangyijing@huawei.com>
> ---
> arch/alpha/include/asm/pci.h | 2 +-
> arch/alpha/kernel/sys_nautilus.c | 2 +-
> arch/cris/include/asm/pci.h | 2 +-
> arch/ia64/include/asm/pci.h | 2 +-
> arch/m68k/coldfire/pci.c | 2 +-
> arch/mips/include/asm/pci.h | 2 +-
> arch/mn10300/include/asm/pci.h | 2 +-
> arch/sh/include/asm/pci.h | 2 +-
> arch/sparc/include/asm/pci_32.h | 2 +-
> arch/sparc/include/asm/pci_64.h | 2 +-
> arch/sparc/kernel/pcic.c | 3 ++-
> arch/unicore32/kernel/pci.c | 2 +-
> arch/x86/include/asm/pci.h | 2 +-
> arch/x86/pci/amd_bus.c | 2 +-
> arch/xtensa/include/asm/pci.h | 2 +-
> drivers/parisc/dino.c | 4 ++--
> drivers/pci/hotplug/ibmphp_core.c | 2 +-
> 17 files changed, 19 insertions(+), 18 deletions(-)
>
> diff --git a/arch/alpha/include/asm/pci.h b/arch/alpha/include/asm/pci.h
> index f7f680f..157925a 100644
> --- a/arch/alpha/include/asm/pci.h
> +++ b/arch/alpha/include/asm/pci.h
> @@ -49,7 +49,7 @@ struct pci_controller {
> void *sysdata;
> };
>
> -/* Override the logic in pci_scan_bus for skipping already-configured
> +/* Override the logic in pci_scan_root_bus for skipping already-configured
> bus numbers. */
>
> #define pcibios_assign_all_busses() 1
> diff --git a/arch/alpha/kernel/sys_nautilus.c b/arch/alpha/kernel/sys_nautilus.c
> index 837c0fa..1047ab3 100644
> --- a/arch/alpha/kernel/sys_nautilus.c
> +++ b/arch/alpha/kernel/sys_nautilus.c
> @@ -206,7 +206,7 @@ nautilus_init_pci(void)
> unsigned long memtop = max_low_pfn << PAGE_SHIFT;
>
> /* Scan our single hose. */
> - bus = pci_scan_bus(0, alpha_mv.pci_ops, hose);
> + bus = pci_scan_root_bus(NULL, 0, alpha_mv.pci_ops, hose, NULL);
> hose->bus = bus;
> pcibios_claim_one_bus(bus);
>
> diff --git a/arch/cris/include/asm/pci.h b/arch/cris/include/asm/pci.h
> index cc2399c..96b33a6 100644
> --- a/arch/cris/include/asm/pci.h
> +++ b/arch/cris/include/asm/pci.h
> @@ -5,7 +5,7 @@
> #ifdef __KERNEL__
> #include <linux/mm.h> /* for struct page */
>
> -/* Can be used to override the logic in pci_scan_bus for skipping
> +/* Can be used to override the logic in pci_scan_root_bus for skipping
> already-configured bus numbers - to be used for buggy BIOSes
> or architectures with incomplete PCI setup by the loader */
>
> diff --git a/arch/ia64/include/asm/pci.h b/arch/ia64/include/asm/pci.h
> index 52af5ed..64b34d6 100644
> --- a/arch/ia64/include/asm/pci.h
> +++ b/arch/ia64/include/asm/pci.h
> @@ -20,7 +20,7 @@ struct pci_vector_struct {
> };
>
> /*
> - * Can be used to override the logic in pci_scan_bus for skipping already-configured bus
> + * Can be used to override the logic in pci_scan_root_bus for skipping already-configured bus
> * numbers - to be used for buggy BIOSes or architectures with incomplete PCI setup by the
> * loader.
> */
> diff --git a/arch/m68k/coldfire/pci.c b/arch/m68k/coldfire/pci.c
> index df96792..4d242fb 100644
> --- a/arch/m68k/coldfire/pci.c
> +++ b/arch/m68k/coldfire/pci.c
> @@ -312,7 +312,7 @@ static int __init mcf_pci_init(void)
> set_current_state(TASK_UNINTERRUPTIBLE);
> schedule_timeout(msecs_to_jiffies(200));
>
> - rootbus = pci_scan_bus(0, &mcf_pci_ops, NULL);
> + rootbus = pci_scan_root_bus(NULL, 0, &mcf_pci_ops, NULL, NULL);
> rootbus->resource[0] = &mcf_pci_io;
> rootbus->resource[1] = &mcf_pci_mem;
>
> diff --git a/arch/mips/include/asm/pci.h b/arch/mips/include/asm/pci.h
> index 974b0e3..212030a 100644
> --- a/arch/mips/include/asm/pci.h
> +++ b/arch/mips/include/asm/pci.h
> @@ -60,7 +60,7 @@ extern void register_pci_controller(struct pci_controller *hose);
> extern int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin);
>
>
> -/* Can be used to override the logic in pci_scan_bus for skipping
> +/* Can be used to override the logic in pci_scan_root_bus for skipping
> already-configured bus numbers - to be used for buggy BIOSes
> or architectures with incomplete PCI setup by the loader */
>
> diff --git a/arch/mn10300/include/asm/pci.h b/arch/mn10300/include/asm/pci.h
> index 5f70af2..6305f14 100644
> --- a/arch/mn10300/include/asm/pci.h
> +++ b/arch/mn10300/include/asm/pci.h
> @@ -33,7 +33,7 @@ do { \
> #define __pcidebug(FMT, BUS, DEVFN, WHERE, ...) do {} while (0)
> #endif
>
> -/* Can be used to override the logic in pci_scan_bus for skipping
> +/* Can be used to override the logic in pci_scan_root_bus for skipping
> * already-configured bus numbers - to be used for buggy BIOSes or
> * architectures with incomplete PCI setup by the loader */
>
> diff --git a/arch/sh/include/asm/pci.h b/arch/sh/include/asm/pci.h
> index 5b45115..69bcb78 100644
> --- a/arch/sh/include/asm/pci.h
> +++ b/arch/sh/include/asm/pci.h
> @@ -3,7 +3,7 @@
>
> #ifdef __KERNEL__
>
> -/* Can be used to override the logic in pci_scan_bus for skipping
> +/* Can be used to override the logic in pci_scan_root_bus for skipping
> already-configured bus numbers - to be used for buggy BIOSes
> or architectures with incomplete PCI setup by the loader */
>
> diff --git a/arch/sparc/include/asm/pci_32.h b/arch/sparc/include/asm/pci_32.h
> index 53e9b49..4ef6064 100644
> --- a/arch/sparc/include/asm/pci_32.h
> +++ b/arch/sparc/include/asm/pci_32.h
> @@ -5,7 +5,7 @@
>
> #include <linux/dma-mapping.h>
>
> -/* Can be used to override the logic in pci_scan_bus for skipping
> +/* Can be used to override the logic in pci_scan_root_bus for skipping
> * already-configured bus numbers - to be used for buggy BIOSes
> * or architectures with incomplete PCI setup by the loader.
> */
> diff --git a/arch/sparc/include/asm/pci_64.h b/arch/sparc/include/asm/pci_64.h
> index bd00a62..6e017f9 100644
> --- a/arch/sparc/include/asm/pci_64.h
> +++ b/arch/sparc/include/asm/pci_64.h
> @@ -5,7 +5,7 @@
>
> #include <linux/dma-mapping.h>
>
> -/* Can be used to override the logic in pci_scan_bus for skipping
> +/* Can be used to override the logic in pci_scan_root_bus for skipping
> * already-configured bus numbers - to be used for buggy BIOSes
> * or architectures with incomplete PCI setup by the loader.
> */
> diff --git a/arch/sparc/kernel/pcic.c b/arch/sparc/kernel/pcic.c
> index 6cc78c2..64aafac 100644
> --- a/arch/sparc/kernel/pcic.c
> +++ b/arch/sparc/kernel/pcic.c
> @@ -390,7 +390,8 @@ static void __init pcic_pbm_scan_bus(struct linux_pcic *pcic)
> {
> struct linux_pbm_info *pbm = &pcic->pbm;
>
> - pbm->pci_bus = pci_scan_bus(pbm->pci_first_busno, &pcic_ops, pbm);
> + pbm->pci_bus = pci_scan_root_bus(NULL, pbm->pci_first_busno,
> + &pcic_ops, pbm, NULL);
> #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/unicore32/kernel/pci.c b/arch/unicore32/kernel/pci.c
> index 374a055..be0f261 100644
> --- a/arch/unicore32/kernel/pci.c
> +++ b/arch/unicore32/kernel/pci.c
> @@ -258,7 +258,7 @@ static int __init pci_common_init(void)
>
> pci_puv3_preinit();
>
> - puv3_bus = pci_scan_bus(0, &pci_puv3_ops, NULL);
> + puv3_bus = pci_scan_root_bus(NULL, 0, &pci_puv3_ops, NULL, NULL);
>
> if (!puv3_bus)
> panic("PCI: unable to scan bus!");
> diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h
> index 0892ea0..0540ff7 100644
> --- a/arch/x86/include/asm/pci.h
> +++ b/arch/x86/include/asm/pci.h
> @@ -41,7 +41,7 @@ static inline int pci_proc_domain(struct pci_bus *bus)
> }
> #endif
>
> -/* Can be used to override the logic in pci_scan_bus for skipping
> +/* Can be used to override the logic in pci_scan_root_bus for skipping
> already-configured bus numbers - to be used for buggy BIOSes
> or architectures with incomplete PCI setup by the loader */
>
> diff --git a/arch/x86/pci/amd_bus.c b/arch/x86/pci/amd_bus.c
> index c20d2cc..baf6209 100644
> --- a/arch/x86/pci/amd_bus.c
> +++ b/arch/x86/pci/amd_bus.c
> @@ -52,7 +52,7 @@ static struct pci_root_info __init *find_pci_root_info(int node, int link)
>
> /**
> * early_root_info_init()
> - * called before pcibios_scan_root and pci_scan_bus
> + * called before pcibios_scan_root and pci_scan_root_bus
> * fills the mp_bus_to_cpumask array based according
> * to the LDT Bus Number Registers found in the northbridge.
> */
> diff --git a/arch/xtensa/include/asm/pci.h b/arch/xtensa/include/asm/pci.h
> index 5d52dc4..377fae9 100644
> --- a/arch/xtensa/include/asm/pci.h
> +++ b/arch/xtensa/include/asm/pci.h
> @@ -13,7 +13,7 @@
>
> #ifdef __KERNEL__
>
> -/* Can be used to override the logic in pci_scan_bus for skipping
> +/* Can be used to override the logic in pci_scan_root_bus for skipping
> * already-configured bus numbers - to be used for buggy BIOSes
> * or architectures with incomplete PCI setup by the loader
> */
> diff --git a/drivers/parisc/dino.c b/drivers/parisc/dino.c
> index a0580af..67c31bd 100644
> --- a/drivers/parisc/dino.c
> +++ b/drivers/parisc/dino.c
> @@ -74,7 +74,7 @@
> ** assigned a PCI bus number based on "when" it's discovered.
> **
> ** The "secondary" bus number is set to this before calling
> -** pci_scan_bus(). If any PPB's are present, the scan will
> +** pci_scan_root_bus(). If any PPB's are present, the scan will
> ** discover them and update the "secondary" and "subordinate"
> ** fields in Dino's pci_bus structure.
> **
> @@ -787,7 +787,7 @@ static int __init dino_common_init(struct parisc_device *dev,
>
> pcibios_register_hba(&dino_dev->hba);
>
> - pci_bios = &dino_bios_ops; /* used by pci_scan_bus() */
> + pci_bios = &dino_bios_ops;
> pci_port = &dino_port_ops;
>
> /*
> diff --git a/drivers/pci/hotplug/ibmphp_core.c b/drivers/pci/hotplug/ibmphp_core.c
> index 3efaf4c..b486432 100644
> --- a/drivers/pci/hotplug/ibmphp_core.c
> +++ b/drivers/pci/hotplug/ibmphp_core.c
> @@ -767,7 +767,7 @@ static u8 bus_structure_fixup(u8 busno)
> (l != 0x0000) && (l != 0xffff)) {
> debug("%s - Inside bus_structure_fixup()\n",
> __func__);
> - pci_scan_bus(busno, ibmphp_pci_bus->ops, NULL);
> + pci_scan_root_bus(NULL, busno, ibmphp_pci_bus->ops, NULL, NULL);
> break;
> }
> }
> --
> 1.7.1
>
> --
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| but they're not |
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