On Thu, Jun 6, 2013 at 10:10 AM, Jiang Liu <liuj97@xxxxxxxxx> wrote: > This patch makes PCI host bridge/bus creating and destroying logic > symmetric by using device_initialize()/device_add()/device_del()/put_device() > pairs as discussed in thread at: > http://comments.gmane.org/gmane.linux.kernel.pci/22073 > > It also fixes a bug in error recovery path in pci_create_root_bus() > which may kfree() an in-use host bridge object. > > Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxx> > Cc: Yinghai Lu <yinghai@xxxxxxxxxx> > --- > drivers/pci/probe.c | 92 +++++++++++++++++++++++----------------------------- > drivers/pci/remove.c | 3 +- > 2 files changed, 42 insertions(+), 53 deletions(-) > > diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c > index 2f81a0a..9e9cdfe 100644 > --- a/drivers/pci/probe.c > +++ b/drivers/pci/probe.c > @@ -470,7 +470,7 @@ void pci_read_bridge_bases(struct pci_bus *child) > } > } > > -static struct pci_bus * pci_alloc_bus(void) > +static struct pci_bus *pci_alloc_bus(struct pci_ops *ops, void *sd, int bus) > { > struct pci_bus *b; > > @@ -483,10 +483,32 @@ static struct pci_bus * pci_alloc_bus(void) > INIT_LIST_HEAD(&b->resources); > b->max_bus_speed = PCI_SPEED_UNKNOWN; > b->cur_bus_speed = PCI_SPEED_UNKNOWN; > + b->sysdata = sd; > + b->ops = ops; > + b->number = bus; > + b->busn_res.start = bus; > + b->busn_res.end = 0xff; > + b->busn_res.flags = IORESOURCE_BUS; > + b->dev.class = &pcibus_class; > + dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus); > + device_initialize(&b->dev); > } > + > return b; > } > > +static void pci_release_host_bridge_dev(struct device *dev) > +{ > + struct pci_host_bridge *bridge = to_pci_host_bridge(dev); > + > + if (bridge->release_fn) > + bridge->release_fn(bridge); > + > + pci_free_resource_list(&bridge->windows); > + > + kfree(bridge); > +} > + should split pci_release_host_bridge_dev renaming and moving to another patch. > static struct pci_host_bridge *pci_alloc_host_bridge(struct pci_bus *b) > { > struct pci_host_bridge *bridge; > @@ -495,6 +517,10 @@ static struct pci_host_bridge *pci_alloc_host_bridge(struct pci_bus *b) > if (bridge) { > INIT_LIST_HEAD(&bridge->windows); > bridge->bus = b; > + bridge->dev.release = pci_release_host_bridge_dev; > + dev_set_name(&bridge->dev, "pci%04x:%02x", > + pci_domain_nr(b), b->number); > + device_initialize(&bridge->dev); > } > > return bridge; > @@ -647,28 +673,13 @@ static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent, > /* > * Allocate a new bus, and inherit stuff from the parent.. > */ > - child = pci_alloc_bus(); > + child = pci_alloc_bus(parent->ops, parent->sysdata, busnr); > if (!child) > return NULL; > > child->parent = parent; > - child->ops = parent->ops; > - child->sysdata = parent->sysdata; > child->bus_flags = parent->bus_flags; > - > - /* initialize some portions of the bus device, but don't register it > - * now as the parent is not properly set up yet. > - */ > - child->dev.class = &pcibus_class; > - dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr); > - > - /* > - * Set up the primary, secondary and subordinate > - * bus numbers. > - */ > - child->number = child->busn_res.start = busnr; > child->primary = parent->busn_res.start; > - child->busn_res.end = 0xff; > > if (!bridge) { > child->dev.parent = parent->bridge; > @@ -689,7 +700,7 @@ static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent, > bridge->subordinate = child; > > add_dev: > - ret = device_register(&child->dev); > + ret = device_add(&child->dev); > WARN_ON(ret < 0); > > pcibios_add_bus(child); > @@ -1208,18 +1219,6 @@ int pci_cfg_space_size(struct pci_dev *dev) > return PCI_CFG_SPACE_SIZE; > } > > -static void pci_release_bus_bridge_dev(struct device *dev) > -{ > - struct pci_host_bridge *bridge = to_pci_host_bridge(dev); > - > - if (bridge->release_fn) > - bridge->release_fn(bridge); > - > - pci_free_resource_list(&bridge->windows); > - > - kfree(bridge); > -} > - > struct pci_dev *pci_alloc_dev(struct pci_bus *bus) > { > struct pci_dev *dev; > @@ -1707,13 +1706,10 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, > char bus_addr[64]; > char *fmt; > > - b = pci_alloc_bus(); > + b = pci_alloc_bus(ops, sysdata, bus); > if (!b) > return NULL; > > - b->sysdata = sysdata; > - b->ops = ops; > - b->number = b->busn_res.start = bus; > b2 = pci_find_bus(pci_domain_nr(b), bus); > if (b2) { > /* If we already got to this bus through a different bridge, ignore it */ > @@ -1726,30 +1722,21 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, > goto err_out; > > bridge->dev.parent = parent; > - bridge->dev.release = pci_release_bus_bridge_dev; > - dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(b), bus); > error = pcibios_root_bridge_prepare(bridge); > - if (error) { > - kfree(bridge); > - goto err_out; > - } > + if (error) > + goto bridge_dev_reg_err; > + > + error = device_add(&bridge->dev); > + if (error) > + goto bridge_dev_reg_err; > > - error = device_register(&bridge->dev); > - if (error) { > - kfree(bridge); > - goto err_out; > - } > b->bridge = get_device(&bridge->dev); > device_enable_async_suspend(b->bridge); > pci_set_bus_of_node(b); > - > if (!parent) > set_dev_node(b->bridge, pcibus_to_node(b)); > - > - b->dev.class = &pcibus_class; > b->dev.parent = b->bridge; > - dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus); > - error = device_register(&b->dev); > + error = device_add(&b->dev); > if (error) > goto class_dev_reg_err; > > @@ -1792,10 +1779,11 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, > return b; > > class_dev_reg_err: > + device_del(&bridge->dev); > +bridge_dev_reg_err: > put_device(&bridge->dev); > - device_unregister(&bridge->dev); > err_out: > - kfree(b); > + put_device(&b->dev); > return NULL; > } > > diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c > index 8fc54b7..b0ce875 100644 > --- a/drivers/pci/remove.c > +++ b/drivers/pci/remove.c > @@ -52,7 +52,8 @@ void pci_remove_bus(struct pci_bus *bus) > up_write(&pci_bus_sem); > pci_remove_legacy_files(bus); > pcibios_remove_bus(bus); > - device_unregister(&bus->dev); > + device_del(&bus->dev); > + put_device(&bus->dev); > } > EXPORT_SYMBOL(pci_remove_bus); > looks like we don't need to split device_register to device_del and put_device. we can make root bus removal to use device_unregister too, in the patches, https://patchwork.kernel.org/patch/2562431/ [1/7] PCI: move back pci_proc_attach_devices calling https://patchwork.kernel.org/patch/2562461/ [2/7] PCI: move resources and bus_list releasing to pci_release_dev https://patchwork.kernel.org/patch/2562451/ [3/7] PCI: Detach driver in pci_stop_device Yinghai -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
