From e277d2fc79d6abb86fafadb58dca0b9c498a9aa7 Mon Sep 17 00:00:00 2001 From: Yu Zhao Date: Mon, 18 May 2009 13:51:33 +0800 Subject: PCI: handle Virtual Function ATS enabling The SR-IOV spec requires that the Smallest Translation Unit and the Invalidate Queue Depth fields in the Virtual Function ATS capability are hardwired to 0. If a function is a Virtual Function, then and set its Physical Function's STU before enabling the ATS. Signed-off-by: Yu Zhao Acked-by: Jesse Barnes Signed-off-by: David Woodhouse --- drivers/pci/iov.c | 66 +++++++++++++++++++++++++++++++++++++++++++------------ drivers/pci/pci.h | 4 +++- 2 files changed, 55 insertions(+), 15 deletions(-) (limited to 'drivers') diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c index 0a7a1b40286f..415140499ffb 100644 --- a/drivers/pci/iov.c +++ b/drivers/pci/iov.c @@ -491,10 +491,10 @@ found: if (pdev) iov->dev = pci_dev_get(pdev); - else { + else iov->dev = dev; - mutex_init(&iov->lock); - } + + mutex_init(&iov->lock); dev->sriov = iov; dev->is_physfn = 1; @@ -514,11 +514,11 @@ static void sriov_release(struct pci_dev *dev) { BUG_ON(dev->sriov->nr_virtfn); - if (dev == dev->sriov->dev) - mutex_destroy(&dev->sriov->lock); - else + if (dev != dev->sriov->dev) pci_dev_put(dev->sriov->dev); + mutex_destroy(&dev->sriov->lock); + kfree(dev->sriov); dev->sriov = NULL; } @@ -723,19 +723,40 @@ int pci_enable_ats(struct pci_dev *dev, int ps) int rc; u16 ctrl; - BUG_ON(dev->ats); + BUG_ON(dev->ats && dev->ats->is_enabled); if (ps < PCI_ATS_MIN_STU) return -EINVAL; - rc = ats_alloc_one(dev, ps); - if (rc) - return rc; + if (dev->is_physfn || dev->is_virtfn) { + struct pci_dev *pdev = dev->is_physfn ? dev : dev->physfn; + + mutex_lock(&pdev->sriov->lock); + if (pdev->ats) + rc = pdev->ats->stu == ps ? 0 : -EINVAL; + else + rc = ats_alloc_one(pdev, ps); + + if (!rc) + pdev->ats->ref_cnt++; + mutex_unlock(&pdev->sriov->lock); + if (rc) + return rc; + } + + if (!dev->is_physfn) { + rc = ats_alloc_one(dev, ps); + if (rc) + return rc; + } ctrl = PCI_ATS_CTRL_ENABLE; - ctrl |= PCI_ATS_CTRL_STU(ps - PCI_ATS_MIN_STU); + if (!dev->is_virtfn) + ctrl |= PCI_ATS_CTRL_STU(ps - PCI_ATS_MIN_STU); pci_write_config_word(dev, dev->ats->pos + PCI_ATS_CTRL, ctrl); + dev->ats->is_enabled = 1; + return 0; } @@ -747,13 +768,26 @@ void pci_disable_ats(struct pci_dev *dev) { u16 ctrl; - BUG_ON(!dev->ats); + BUG_ON(!dev->ats || !dev->ats->is_enabled); pci_read_config_word(dev, dev->ats->pos + PCI_ATS_CTRL, &ctrl); ctrl &= ~PCI_ATS_CTRL_ENABLE; pci_write_config_word(dev, dev->ats->pos + PCI_ATS_CTRL, ctrl); - ats_free_one(dev); + dev->ats->is_enabled = 0; + + if (dev->is_physfn || dev->is_virtfn) { + struct pci_dev *pdev = dev->is_physfn ? dev : dev->physfn; + + mutex_lock(&pdev->sriov->lock); + pdev->ats->ref_cnt--; + if (!pdev->ats->ref_cnt) + ats_free_one(pdev); + mutex_unlock(&pdev->sriov->lock); + } + + if (!dev->is_physfn) + ats_free_one(dev); } /** @@ -765,13 +799,17 @@ void pci_disable_ats(struct pci_dev *dev) * The ATS spec uses 0 in the Invalidate Queue Depth field to * indicate that the function can accept 32 Invalidate Request. * But here we use the `real' values (i.e. 1~32) for the Queue - * Depth. + * Depth; and 0 indicates the function shares the Queue with + * other functions (doesn't exclusively own a Queue). */ int pci_ats_queue_depth(struct pci_dev *dev) { int pos; u16 cap; + if (dev->is_virtfn) + return 0; + if (dev->ats) return dev->ats->qdep; diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 3c2ec64f78e9..f73bcbedf37c 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -234,6 +234,8 @@ struct pci_ats { int pos; /* capability position */ int stu; /* Smallest Translation Unit */ int qdep; /* Invalidate Queue Depth */ + int ref_cnt; /* Physical Function reference count */ + int is_enabled:1; /* Enable bit is set */ }; #ifdef CONFIG_PCI_IOV @@ -255,7 +257,7 @@ extern int pci_ats_queue_depth(struct pci_dev *dev); */ static inline int pci_ats_enabled(struct pci_dev *dev) { - return !!dev->ats; + return dev->ats && dev->ats->is_enabled; } #else static inline int pci_iov_init(struct pci_dev *dev) -- cgit v1.2.2