| Message ID | 1369489718-25869-10-git-send-email-jiang.liu@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On Sat, May 25, 2013 at 6:48 AM, Jiang Liu <liuj97@gmail.com> wrote: > Trivial changes to IOV: > 1) use new PCI interfaces to simplify IOV implementation > 2) fix some reference count related race windows > > Signed-off-by: Jiang Liu <jiang.liu@huawei.com> > Cc: Donald Dutile <ddutile@redhat.com> > Cc: Yinghai Lu <yinghai@kernel.org> > Cc: Ram Pai <linuxram@us.ibm.com> > Cc: linux-pci@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > --- > drivers/pci/iov.c | 58 +++++++++++++++++++++---------------------------------- > 1 file changed, 22 insertions(+), 36 deletions(-) > > diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c > index 8f1e117..3e33499 100644 > --- a/drivers/pci/iov.c > +++ b/drivers/pci/iov.c > @@ -51,43 +51,30 @@ static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr) > return child; > } > > -static void virtfn_remove_bus(struct pci_bus *bus, int busnr) > +static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus) > { > - struct pci_bus *child; > - > - if (bus->number == busnr) > - return; > - > - child = pci_find_bus(pci_domain_nr(bus), busnr); > - BUG_ON(!child); > - > - if (list_empty(&child->devices)) > - pci_remove_bus(child); > + if (physbus != virtbus && list_empty(&virtbus->devices)) > + pci_remove_bus(virtbus); > } > > static int virtfn_add(struct pci_dev *dev, int id, int reset) > { > int i; > - int rc; > + int rc = -ENOMEM; > u64 size; > char buf[VIRTFN_ID_LEN]; > - struct pci_dev *virtfn; > + struct pci_dev *virtfn = NULL; > struct resource *res; > struct pci_sriov *iov = dev->sriov; > struct pci_bus *bus; > > - virtfn = pci_alloc_dev(NULL); > - if (!virtfn) > - return -ENOMEM; > - > mutex_lock(&iov->dev->sriov->lock); > bus = virtfn_add_bus(dev->bus, virtfn_bus(dev, id)); > - if (!bus) { > - kfree(virtfn); > - mutex_unlock(&iov->dev->sriov->lock); > - return -ENOMEM; > - } > - virtfn->bus = pci_bus_get(bus); > + if (bus) > + virtfn = pci_alloc_dev(bus); > + if (!virtfn) > + goto failed0; > + > virtfn->devfn = virtfn_devfn(dev, id); > virtfn->vendor = dev->vendor; > pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_DID, &virtfn->device); > @@ -136,7 +123,8 @@ failed1: > pci_dev_put(dev); > mutex_lock(&iov->dev->sriov->lock); > pci_stop_and_remove_bus_device(virtfn); > - virtfn_remove_bus(dev->bus, virtfn_bus(dev, id)); > + virtfn_remove_bus(dev->bus, bus); > +failed0: need to swap above two lines. otherwise virtual bus could not be removed. > mutex_unlock(&iov->dev->sriov->lock); > > return rc; > @@ -145,20 +133,15 @@ failed1: > static void virtfn_remove(struct pci_dev *dev, int id, int reset) > { > char buf[VIRTFN_ID_LEN]; > - struct pci_bus *bus; > struct pci_dev *virtfn; > struct pci_sriov *iov = dev->sriov; > > - bus = pci_find_bus(pci_domain_nr(dev->bus), virtfn_bus(dev, id)); > - if (!bus) > - return; > - > - virtfn = pci_get_slot(bus, virtfn_devfn(dev, id)); > + virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus), > + virtfn_bus(dev, id), > + virtfn_devfn(dev, id)); > if (!virtfn) > return; > > - pci_dev_put(virtfn); > - > if (reset) { > device_release_driver(&virtfn->dev); > __pci_reset_function(virtfn); > @@ -176,9 +159,11 @@ static void virtfn_remove(struct pci_dev *dev, int id, int reset) > > mutex_lock(&iov->dev->sriov->lock); > pci_stop_and_remove_bus_device(virtfn); > - virtfn_remove_bus(dev->bus, virtfn_bus(dev, id)); > + virtfn_remove_bus(dev->bus, virtfn->bus); > mutex_unlock(&iov->dev->sriov->lock); > > + /* balance pci_get_domain_bus_and_slot() */ > + pci_dev_put(virtfn); > pci_dev_put(dev); > } > > @@ -335,13 +320,14 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn) > if (!pdev) > return -ENODEV; > > - pci_dev_put(pdev); > - > - if (!pdev->is_physfn) > + if (!pdev->is_physfn) { > + pci_dev_put(pdev); > return -ENODEV; > + } > > rc = sysfs_create_link(&dev->dev.kobj, > &pdev->dev.kobj, "dep_link"); > + pci_dev_put(pdev); > if (rc) > return rc; > } > -- > 1.8.1.2 > -- 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/drivers/pci/iov.c b/drivers/pci/iov.c index 8f1e117..3e33499 100644 --- a/drivers/pci/iov.c +++ b/drivers/pci/iov.c @@ -51,43 +51,30 @@ static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr) return child; } -static void virtfn_remove_bus(struct pci_bus *bus, int busnr) +static void virtfn_remove_bus(struct pci_bus *physbus, struct pci_bus *virtbus) { - struct pci_bus *child; - - if (bus->number == busnr) - return; - - child = pci_find_bus(pci_domain_nr(bus), busnr); - BUG_ON(!child); - - if (list_empty(&child->devices)) - pci_remove_bus(child); + if (physbus != virtbus && list_empty(&virtbus->devices)) + pci_remove_bus(virtbus); } static int virtfn_add(struct pci_dev *dev, int id, int reset) { int i; - int rc; + int rc = -ENOMEM; u64 size; char buf[VIRTFN_ID_LEN]; - struct pci_dev *virtfn; + struct pci_dev *virtfn = NULL; struct resource *res; struct pci_sriov *iov = dev->sriov; struct pci_bus *bus; - virtfn = pci_alloc_dev(NULL); - if (!virtfn) - return -ENOMEM; - mutex_lock(&iov->dev->sriov->lock); bus = virtfn_add_bus(dev->bus, virtfn_bus(dev, id)); - if (!bus) { - kfree(virtfn); - mutex_unlock(&iov->dev->sriov->lock); - return -ENOMEM; - } - virtfn->bus = pci_bus_get(bus); + if (bus) + virtfn = pci_alloc_dev(bus); + if (!virtfn) + goto failed0; + virtfn->devfn = virtfn_devfn(dev, id); virtfn->vendor = dev->vendor; pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_DID, &virtfn->device); @@ -136,7 +123,8 @@ failed1: pci_dev_put(dev); mutex_lock(&iov->dev->sriov->lock); pci_stop_and_remove_bus_device(virtfn); - virtfn_remove_bus(dev->bus, virtfn_bus(dev, id)); + virtfn_remove_bus(dev->bus, bus); +failed0: mutex_unlock(&iov->dev->sriov->lock); return rc; @@ -145,20 +133,15 @@ failed1: static void virtfn_remove(struct pci_dev *dev, int id, int reset) { char buf[VIRTFN_ID_LEN]; - struct pci_bus *bus; struct pci_dev *virtfn; struct pci_sriov *iov = dev->sriov; - bus = pci_find_bus(pci_domain_nr(dev->bus), virtfn_bus(dev, id)); - if (!bus) - return; - - virtfn = pci_get_slot(bus, virtfn_devfn(dev, id)); + virtfn = pci_get_domain_bus_and_slot(pci_domain_nr(dev->bus), + virtfn_bus(dev, id), + virtfn_devfn(dev, id)); if (!virtfn) return; - pci_dev_put(virtfn); - if (reset) { device_release_driver(&virtfn->dev); __pci_reset_function(virtfn); @@ -176,9 +159,11 @@ static void virtfn_remove(struct pci_dev *dev, int id, int reset) mutex_lock(&iov->dev->sriov->lock); pci_stop_and_remove_bus_device(virtfn); - virtfn_remove_bus(dev->bus, virtfn_bus(dev, id)); + virtfn_remove_bus(dev->bus, virtfn->bus); mutex_unlock(&iov->dev->sriov->lock); + /* balance pci_get_domain_bus_and_slot() */ + pci_dev_put(virtfn); pci_dev_put(dev); } @@ -335,13 +320,14 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn) if (!pdev) return -ENODEV; - pci_dev_put(pdev); - - if (!pdev->is_physfn) + if (!pdev->is_physfn) { + pci_dev_put(pdev); return -ENODEV; + } rc = sysfs_create_link(&dev->dev.kobj, &pdev->dev.kobj, "dep_link"); + pci_dev_put(pdev); if (rc) return rc; }
Trivial changes to IOV: 1) use new PCI interfaces to simplify IOV implementation 2) fix some reference count related race windows Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Donald Dutile <ddutile@redhat.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Ram Pai <linuxram@us.ibm.com> Cc: linux-pci@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- drivers/pci/iov.c | 58 +++++++++++++++++++++---------------------------------- 1 file changed, 22 insertions(+), 36 deletions(-)