From patchwork Wed Jun 19 22:03:43 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Dey, Megha" X-Patchwork-Id: 1119023 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.intel.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 45Tdgv5lHCz9s9y for ; Thu, 20 Jun 2019 07:41:47 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730616AbfFSVlq (ORCPT ); Wed, 19 Jun 2019 17:41:46 -0400 Received: from mga11.intel.com ([192.55.52.93]:10385 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730578AbfFSVlq (ORCPT ); Wed, 19 Jun 2019 17:41:46 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 19 Jun 2019 14:41:45 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.63,394,1557212400"; d="scan'208";a="170683468" Received: from megha-z97x-ud7-th.sc.intel.com ([143.183.85.162]) by orsmga002.jf.intel.com with ESMTP; 19 Jun 2019 14:41:45 -0700 From: Megha Dey To: bhelgaas@google.com, linux-pci@vger.kernel.org Cc: ashok.raj@intel.com, jacob.jun.pan@linux.intel.com, megha.dey@intel.com, Megha Dey Subject: [RFC V1 5/6] PCI/MSI: Free MSI-X resources by group Date: Wed, 19 Jun 2019 15:03:43 -0700 Message-Id: <1560981824-3966-6-git-send-email-megha.dey@linux.intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1560981824-3966-1-git-send-email-megha.dey@linux.intel.com> References: <1560981824-3966-1-git-send-email-megha.dey@linux.intel.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Currently, the pci_free_irq_vectors() frees all the allocated resources associated with a PCIe device when the device is being shut down. With the introduction of dynamic allocation of MSI-X vectors by group ID, there should exist an API which can free the resources allocated only to a particular group, which can be called even if the device is not being shut down. The pci_free_irq_vectors_grp() function provides this type of interface. The existing pci_free_irq_vectors() can be called along side this API. Cc: Jacob Pan Cc: Ashok Raj Signed-off-by: Megha Dey --- drivers/pci/msi.c | 130 ++++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/msi.h | 2 + include/linux/pci.h | 9 ++++ kernel/irq/msi.c | 26 +++++++++++ 4 files changed, 167 insertions(+) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index e947243..342e267 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -53,9 +53,23 @@ static void pci_msi_teardown_msi_irqs(struct pci_dev *dev) else arch_teardown_msi_irqs(dev); } + +static void pci_msi_teardown_msi_irqs_grp(struct pci_dev *dev, int group_id) +{ + struct irq_domain *domain; + + domain = dev_get_msi_domain(&dev->dev); + + if (domain && irq_domain_is_hierarchy(domain)) + msi_domain_free_irqs_grp(domain, &dev->dev, group_id); + else + arch_teardown_msi_irqs_grp(dev, group_id); +} + #else #define pci_msi_setup_msi_irqs arch_setup_msi_irqs #define pci_msi_teardown_msi_irqs arch_teardown_msi_irqs +#define pci_msi_teardown_msi_irqs_grp default_teardown_msi_irqs_grp #endif /* Arch hooks */ @@ -373,6 +387,7 @@ static void free_msi_irqs(struct pci_dev *dev) list_for_each_entry_safe(entry, tmp, msi_list, list) { if (entry->msi_attrib.is_msix) { + clear_bit(entry->msi_attrib.entry_nr, dev->entry); if (list_is_last(&entry->list, msi_list)) iounmap(entry->mask_base); } @@ -381,6 +396,8 @@ static void free_msi_irqs(struct pci_dev *dev) free_msi_entry(entry); } + idr_destroy(dev->grp_idr); + if (dev->msi_irq_groups) { sysfs_remove_groups(&dev->dev.kobj, dev->msi_irq_groups); msi_attrs = dev->msi_irq_groups[0]->attrs; @@ -398,6 +415,60 @@ static void free_msi_irqs(struct pci_dev *dev) } } +static const char msix_sysfs_grp[] = "msi_irqs"; + +static int free_msi_irqs_grp(struct pci_dev *dev, int group_id) +{ + struct list_head *msi_list = dev_to_msi_list(&dev->dev); + struct msi_desc *entry, *tmp; + struct attribute **msi_attrs; + struct device_attribute *dev_attr; + int i; + long vec; + struct msix_sysfs *msix_sysfs_entry, *tmp_msix; + struct list_head *pci_msix = &dev->msix_sysfs; + int num_vec = 0; + + for_each_pci_msi_entry(entry, dev) { + if (entry->group_id == group_id && entry->irq) + for (i = 0; i < entry->nvec_used; i++) + BUG_ON(irq_has_action(entry->irq + i)); + } + + pci_msi_teardown_msi_irqs_grp(dev, group_id); + + list_for_each_entry_safe(entry, tmp, msi_list, list) { + if (entry->group_id == group_id) { + clear_bit(entry->msi_attrib.entry_nr, dev->entry); + list_del(&entry->list); + free_msi_entry(entry); + } + } + + list_for_each_entry_safe(msix_sysfs_entry, tmp_msix, pci_msix, list) { + if (msix_sysfs_entry->group_id == group_id) { + msi_attrs = msix_sysfs_entry->msi_irq_group->attrs; + for (i = 0; i < msix_sysfs_entry->vecs_in_grp; i++) { + if (!i) + num_vec = msix_sysfs_entry->vecs_in_grp; + dev_attr = container_of(msi_attrs[i], + struct device_attribute, attr); + sysfs_remove_file_from_group(&dev->dev.kobj, + &dev_attr->attr, msix_sysfs_grp); + if (kstrtol(dev_attr->attr.name, 10, &vec)) + return -EINVAL; + kfree(dev_attr->attr.name); + kfree(dev_attr); + } + msix_sysfs_entry->msi_irq_group = NULL; + list_del(&msix_sysfs_entry->list); + idr_remove(dev->grp_idr, group_id); + kfree(msix_sysfs_entry); + } + } + return num_vec; +} + static void pci_intx_for_msi(struct pci_dev *dev, int enable) { if (!(dev->dev_flags & PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG)) @@ -1052,6 +1123,45 @@ void pci_disable_msix(struct pci_dev *dev) } EXPORT_SYMBOL(pci_disable_msix); +static void pci_msix_shutdown_grp(struct pci_dev *dev, int group_id) +{ + struct msi_desc *entry; + int grp_present = 0; + + if (pci_dev_is_disconnected(dev)) { + dev->msix_enabled = 0; + return; + } + + /* Return the device with MSI-X masked as initial states */ + for_each_pci_msi_entry(entry, dev) { + if (entry->group_id == group_id) { + /* Keep cached states to be restored */ + __pci_msix_desc_mask_irq(entry, 1); + grp_present = 1; + } + } + + if (!grp_present) { + pci_err(dev, "Group to be disabled not present\n"); + return; + } +} + +int pci_disable_msix_grp(struct pci_dev *dev, int group_id) +{ + int num_vecs; + + if (!pci_msi_enable || !dev) + return -EINVAL; + + pci_msix_shutdown_grp(dev, group_id); + num_vecs = free_msi_irqs_grp(dev, group_id); + + return num_vecs; +} +EXPORT_SYMBOL(pci_disable_msix_grp); + void pci_no_msi(void) { pci_msi_enable = 0; @@ -1356,6 +1466,26 @@ void pci_free_irq_vectors(struct pci_dev *dev) EXPORT_SYMBOL(pci_free_irq_vectors); /** + * pci_free_irq_vectors_grp - free previously allocated IRQs for a + * device associated with a group + * @dev: PCI device to operate on + * @group_id: group to be freed + * + * Undoes the allocations and enabling in pci_alloc_irq_vectors_dyn(). + * Can be only called for MSIx vectors. + */ +int pci_free_irq_vectors_grp(struct pci_dev *dev, int group_id) +{ + if (group_id < 0) { + pci_err(dev, "Group should be > 0\n"); + return -EINVAL; + } + + return pci_disable_msix_grp(dev, group_id); +} +EXPORT_SYMBOL(pci_free_irq_vectors_grp); + +/** * pci_irq_vector - return Linux IRQ number of a device vector * @dev: PCI device to operate on * @nr: device-relative interrupt vector index (0-based). diff --git a/include/linux/msi.h b/include/linux/msi.h index e61ba24..78929ad 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -333,6 +333,8 @@ struct irq_domain *msi_create_irq_domain(struct fwnode_handle *fwnode, int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev, int nvec); void msi_domain_free_irqs(struct irq_domain *domain, struct device *dev); +void msi_domain_free_irqs_grp(struct irq_domain *domain, struct device *dev, + int group_id); struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain); struct irq_domain *platform_msi_create_irq_domain(struct fwnode_handle *fwnode, diff --git a/include/linux/pci.h b/include/linux/pci.h index 73385c0..944e539 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1404,6 +1404,7 @@ int pci_msi_vec_count(struct pci_dev *dev); void pci_disable_msi(struct pci_dev *dev); int pci_msix_vec_count(struct pci_dev *dev); void pci_disable_msix(struct pci_dev *dev); +int pci_disable_msix_grp(struct pci_dev *dev, int group_id); void pci_restore_msi_state(struct pci_dev *dev); int pci_msi_enabled(void); int pci_enable_msi(struct pci_dev *dev); @@ -1428,6 +1429,7 @@ int pci_alloc_irq_vectors_affinity_dyn(struct pci_dev *dev, int *group_id, bool one_shot); void pci_free_irq_vectors(struct pci_dev *dev); +int pci_free_irq_vectors_grp(struct pci_dev *dev, int group_id); int pci_irq_vector(struct pci_dev *dev, unsigned int nr); int pci_irq_vector_group(struct pci_dev *dev, unsigned int nr, unsigned int group_id); @@ -1439,6 +1441,8 @@ static inline int pci_msi_vec_count(struct pci_dev *dev) { return -ENOSYS; } static inline void pci_disable_msi(struct pci_dev *dev) { } static inline int pci_msix_vec_count(struct pci_dev *dev) { return -ENOSYS; } static inline void pci_disable_msix(struct pci_dev *dev) { } +static inline int pci_disable_msix_grp(struct pci_dev *dev, int group_id) + { return -ENOSYS; } static inline void pci_restore_msi_state(struct pci_dev *dev) { } static inline int pci_msi_enabled(void) { return 0; } static inline int pci_enable_msi(struct pci_dev *dev) @@ -1475,6 +1479,11 @@ static inline void pci_free_irq_vectors(struct pci_dev *dev) { } +static inline void pci_free_irq_vectors_grp(struct pci_dev *dev, int group_id) +{ + return 0; +} + static inline int pci_irq_vector(struct pci_dev *dev, unsigned int nr) { if (WARN_ON_ONCE(nr > 0)) diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c index 5cfa931..d73a5dc 100644 --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -511,6 +511,32 @@ void msi_domain_free_irqs(struct irq_domain *domain, struct device *dev) } /** + * msi_domain_free_irqs_grp - Free interrupts belonging to a group from + * a MSI interrupt @domain associated to @dev + * @domain: The domain to managing the interrupts + * @dev: Pointer to device struct of the device for which the interrupt + * should be freed + * @group_id: The group ID to be freed + */ +void msi_domain_free_irqs_grp(struct irq_domain *domain, struct device *dev, + int group_id) +{ + struct msi_desc *desc; + + for_each_msi_entry(desc, dev) { + /* + * We might have failed to allocate an MSI early + * enough that there is no IRQ associated to this + * entry. If that's the case, don't do anything. + */ + if (desc->group_id == group_id && desc->irq) { + irq_domain_free_irqs(desc->irq, desc->nvec_used); + desc->irq = 0; + } + } +} + +/** * msi_get_domain_info - Get the MSI interrupt domain info for @domain * @domain: The interrupt domain to retrieve data from *