| Message ID | edf72769-e9c8-4617-8dc4-8f3d05a678e7@semihalf.com |
|---|---|
| State | Accepted |
| Headers | show |
On Wed, Nov 23, 2016 at 12:21:03PM +0100, Tomasz Nowicki wrote: > Hi Bjorn, > > On 23.11.2016 00:13, Bjorn Helgaas wrote: > >Hi Tomasz, > > > >On Fri, Jun 10, 2016 at 09:55:19PM +0200, Tomasz Nowicki wrote: > >>Implement pci_acpi_scan_root and other arch-specific call so that ARM64 > >>can start using ACPI to setup and enumerate PCI buses. > >> > >>Prior to buses enumeration the pci_acpi_scan_root() implementation looks > >>for configuration space start address (obtained through ACPI _CBA method or > >>MCFG interface). If succeed, it uses ECAM library to create new mapping. > >>Then it attaches generic ECAM ops (pci_generic_ecam_ops) which are used > >>for accessing configuration space later on. > >>... > > > >>+static struct acpi_pci_root_ops acpi_pci_root_ops = { > >>+ .release_info = pci_acpi_generic_release_info, > >>+}; > >>+ > >>+/* Interface called from ACPI code to setup PCI host controller */ > >> struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root) > >> { > >>- /* TODO: Should be revisited when implementing PCI on ACPI */ > >>- return NULL; > >>+ int node = acpi_get_node(root->device->handle); > >>+ struct acpi_pci_generic_root_info *ri; > >>+ struct pci_bus *bus, *child; > >>+ > >>+ ri = kzalloc_node(sizeof(*ri), GFP_KERNEL, node); > >>+ if (!ri) > >>+ return NULL; > >>+ > >>+ ri->cfg = pci_acpi_setup_ecam_mapping(root); > >>+ if (!ri->cfg) { > >>+ kfree(ri); > >>+ return NULL; > >>+ } > >>+ > >>+ acpi_pci_root_ops.pci_ops = &ri->cfg->ops->pci_ops; > > > >This has already been merged, but this isn't right, is it? We're > >writing a host controller-specific pointer into the single system-wide > >acpi_pci_root_ops, then passing it on to acpi_pci_root_create(). > > > >Today, I think ri->cfg->ops->pci_ops is always &pci_generic_ecam_ops, > >from this path: > > > > ri->cfg = pci_acpi_setup_ecam_mapping > > cfg = pci_ecam_create(..., &pci_generic_ecam_ops) > > cfg = kzalloc(...) > > cfg->ops = ops # &pci_generic_ecam_ops > > > >But we're about to merge the ECAM quirks series, which will mean it > >may not be &pci_generic_ecam_ops. Even apart from the ECAM quirks, we > >should avoid this pattern of putting device-specific info in a single > >shared structure because it's too difficult to verify that it's > >correct. > > > > Well spotted. I agree, we need to fix this. How about this: > diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c > index fb439c7..31c0e1c 100644 > --- a/arch/arm64/kernel/pci.c > +++ b/arch/arm64/kernel/pci.c > @@ -152,33 +152,35 @@ static void > pci_acpi_generic_release_info(struct acpi_pci_root_info *ci) > > ri = container_of(ci, struct acpi_pci_generic_root_info, common); > pci_ecam_free(ri->cfg); > + kfree(ci->ops); > kfree(ri); > } > > -static struct acpi_pci_root_ops acpi_pci_root_ops = { > - .release_info = pci_acpi_generic_release_info, > -}; > - > /* Interface called from ACPI code to setup PCI host controller */ > struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root) > { > int node = acpi_get_node(root->device->handle); > struct acpi_pci_generic_root_info *ri; > struct pci_bus *bus, *child; > + struct acpi_pci_root_ops *root_ops; > > ri = kzalloc_node(sizeof(*ri), GFP_KERNEL, node); > if (!ri) > return NULL; > > + root_ops = kzalloc_node(sizeof(*root_ops), GFP_KERNEL, node); > + if (!root_ops) > + return NULL; > + > ri->cfg = pci_acpi_setup_ecam_mapping(root); > if (!ri->cfg) { > kfree(ri); > + kfree(root_ops); > return NULL; > } > > - acpi_pci_root_ops.pci_ops = &ri->cfg->ops->pci_ops; > - bus = acpi_pci_root_create(root, &acpi_pci_root_ops, &ri->common, > - ri->cfg); > + root_ops->release_info = pci_acpi_generic_release_info; > + root_ops->pci_ops = &ri->cfg->ops->pci_ops; > + bus = acpi_pci_root_create(root, root_ops, &ri->common, ri->cfg); > if (!bus) > return NULL; > > Of course, this should be the part of ECAM quirks core patches. > > The other option we have is to remove "struct pci_ops *pci_ops;" > from acpi_pci_root_ops structure and pass struct pci_ops as an extra > argument to acpi_pci_root_create(). What do you think? I think your patch above is fine and avoids the need to change the x86 and ia64 code. Would you mind packaging this up with a changelog and signed-off-by? I can take care of putting it in the ECAM series. Thanks, Bjorn -- 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 23.11.2016 19:22, Bjorn Helgaas wrote: > On Wed, Nov 23, 2016 at 12:21:03PM +0100, Tomasz Nowicki wrote: >> Hi Bjorn, >> >> On 23.11.2016 00:13, Bjorn Helgaas wrote: >>> Hi Tomasz, >>> >>> On Fri, Jun 10, 2016 at 09:55:19PM +0200, Tomasz Nowicki wrote: >>>> Implement pci_acpi_scan_root and other arch-specific call so that ARM64 >>>> can start using ACPI to setup and enumerate PCI buses. >>>> >>>> Prior to buses enumeration the pci_acpi_scan_root() implementation looks >>>> for configuration space start address (obtained through ACPI _CBA method or >>>> MCFG interface). If succeed, it uses ECAM library to create new mapping. >>>> Then it attaches generic ECAM ops (pci_generic_ecam_ops) which are used >>>> for accessing configuration space later on. >>>> ... >>> >>>> +static struct acpi_pci_root_ops acpi_pci_root_ops = { >>>> + .release_info = pci_acpi_generic_release_info, >>>> +}; >>>> + >>>> +/* Interface called from ACPI code to setup PCI host controller */ >>>> struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root) >>>> { >>>> - /* TODO: Should be revisited when implementing PCI on ACPI */ >>>> - return NULL; >>>> + int node = acpi_get_node(root->device->handle); >>>> + struct acpi_pci_generic_root_info *ri; >>>> + struct pci_bus *bus, *child; >>>> + >>>> + ri = kzalloc_node(sizeof(*ri), GFP_KERNEL, node); >>>> + if (!ri) >>>> + return NULL; >>>> + >>>> + ri->cfg = pci_acpi_setup_ecam_mapping(root); >>>> + if (!ri->cfg) { >>>> + kfree(ri); >>>> + return NULL; >>>> + } >>>> + >>>> + acpi_pci_root_ops.pci_ops = &ri->cfg->ops->pci_ops; >>> >>> This has already been merged, but this isn't right, is it? We're >>> writing a host controller-specific pointer into the single system-wide >>> acpi_pci_root_ops, then passing it on to acpi_pci_root_create(). >>> >>> Today, I think ri->cfg->ops->pci_ops is always &pci_generic_ecam_ops, >> >from this path: >>> >>> ri->cfg = pci_acpi_setup_ecam_mapping >>> cfg = pci_ecam_create(..., &pci_generic_ecam_ops) >>> cfg = kzalloc(...) >>> cfg->ops = ops # &pci_generic_ecam_ops >>> >>> But we're about to merge the ECAM quirks series, which will mean it >>> may not be &pci_generic_ecam_ops. Even apart from the ECAM quirks, we >>> should avoid this pattern of putting device-specific info in a single >>> shared structure because it's too difficult to verify that it's >>> correct. >>> >> >> Well spotted. I agree, we need to fix this. How about this: >> diff --git a/arch/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c >> index fb439c7..31c0e1c 100644 >> --- a/arch/arm64/kernel/pci.c >> +++ b/arch/arm64/kernel/pci.c >> @@ -152,33 +152,35 @@ static void >> pci_acpi_generic_release_info(struct acpi_pci_root_info *ci) >> >> ri = container_of(ci, struct acpi_pci_generic_root_info, common); >> pci_ecam_free(ri->cfg); >> + kfree(ci->ops); >> kfree(ri); >> } >> >> -static struct acpi_pci_root_ops acpi_pci_root_ops = { >> - .release_info = pci_acpi_generic_release_info, >> -}; >> - >> /* Interface called from ACPI code to setup PCI host controller */ >> struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root) >> { >> int node = acpi_get_node(root->device->handle); >> struct acpi_pci_generic_root_info *ri; >> struct pci_bus *bus, *child; >> + struct acpi_pci_root_ops *root_ops; >> >> ri = kzalloc_node(sizeof(*ri), GFP_KERNEL, node); >> if (!ri) >> return NULL; >> >> + root_ops = kzalloc_node(sizeof(*root_ops), GFP_KERNEL, node); >> + if (!root_ops) >> + return NULL; >> + >> ri->cfg = pci_acpi_setup_ecam_mapping(root); >> if (!ri->cfg) { >> kfree(ri); >> + kfree(root_ops); >> return NULL; >> } >> >> - acpi_pci_root_ops.pci_ops = &ri->cfg->ops->pci_ops; >> - bus = acpi_pci_root_create(root, &acpi_pci_root_ops, &ri->common, >> - ri->cfg); >> + root_ops->release_info = pci_acpi_generic_release_info; >> + root_ops->pci_ops = &ri->cfg->ops->pci_ops; >> + bus = acpi_pci_root_create(root, root_ops, &ri->common, ri->cfg); >> if (!bus) >> return NULL; >> >> Of course, this should be the part of ECAM quirks core patches. >> >> The other option we have is to remove "struct pci_ops *pci_ops;" >> from acpi_pci_root_ops structure and pass struct pci_ops as an extra >> argument to acpi_pci_root_create(). What do you think? > > I think your patch above is fine and avoids the need to change the x86 and > ia64 code. Would you mind packaging this up with a changelog and > signed-off-by? I can take care of putting it in the ECAM series. > Sure, I have just sent the patch in replay to ECAM quirks V6 patch set. Let us know when you update your branch so we base our quirks on it. Thanks, Tomasz -- 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/arm64/kernel/pci.c b/arch/arm64/kernel/pci.c index fb439c7..31c0e1c 100644 --- a/arch/arm64/kernel/pci.c +++ b/arch/arm64/kernel/pci.c @@ -152,33 +152,35 @@ static void pci_acpi_generic_release_info(struct acpi_pci_root_info *ci) ri = container_of(ci, struct acpi_pci_generic_root_info, common); pci_ecam_free(ri->cfg); + kfree(ci->ops); kfree(ri); } -static struct acpi_pci_root_ops acpi_pci_root_ops = { - .release_info = pci_acpi_generic_release_info, -}; - /* Interface called from ACPI code to setup PCI host controller */ struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root) { int node = acpi_get_node(root->device->handle); struct acpi_pci_generic_root_info *ri; struct pci_bus *bus, *child; + struct acpi_pci_root_ops *root_ops; ri = kzalloc_node(sizeof(*ri), GFP_KERNEL, node); if (!ri) return NULL; + root_ops = kzalloc_node(sizeof(*root_ops), GFP_KERNEL, node); + if (!root_ops) + return NULL; + ri->cfg = pci_acpi_setup_ecam_mapping(root); if (!ri->cfg) { kfree(ri); + kfree(root_ops); return NULL; } - acpi_pci_root_ops.pci_ops = &ri->cfg->ops->pci_ops; - bus = acpi_pci_root_create(root, &acpi_pci_root_ops, &ri->common, - ri->cfg); + root_ops->release_info = pci_acpi_generic_release_info; + root_ops->pci_ops = &ri->cfg->ops->pci_ops; + bus = acpi_pci_root_create(root, root_ops, &ri->common, ri->cfg); if (!bus) return NULL;