From 1c51b50c2995f543d145d3bce78029ac9f8ca6b3 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Thu, 19 Dec 2013 12:30:17 -0800 Subject: [PATCH] PCI/MSI: Export MSI mode using attributes, not kobjects MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The PCI MSI sysfs code is a mess with kobjects for things that don't really need to be kobjects. This patch creates attributes dynamically for the MSI interrupts instead of using kobjects. Note, this removes a directory from sysfs. Old MSI kobjects: pci_device └── msi_irqs    └── 40    └── mode New MSI attributes: pci_device └── msi_irqs    └── 40 As there was only one file "mode" with the kobject model, the interrupt number is now a file that returns the "mode" of the interrupt (msi vs. msix). Signed-off-by: Greg Kroah-Hartman Signed-off-by: Bjorn Helgaas Acked-by: Neil Horman --- Documentation/ABI/testing/sysfs-bus-pci | 11 +- drivers/pci/msi.c | 166 +++++++++++++----------- include/linux/pci.h | 2 +- 3 files changed, 96 insertions(+), 83 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-bus-pci b/Documentation/ABI/testing/sysfs-bus-pci index 5210a51c90fd..a3c5a6685036 100644 --- a/Documentation/ABI/testing/sysfs-bus-pci +++ b/Documentation/ABI/testing/sysfs-bus-pci @@ -70,18 +70,15 @@ Date: September, 2011 Contact: Neil Horman Description: The /sys/devices/.../msi_irqs directory contains a variable set - of sub-directories, with each sub-directory being named after a - corresponding msi irq vector allocated to that device. Each - numbered sub-directory N contains attributes of that irq. - Note that this directory is not created for device drivers which - do not support msi irqs + of files, with each file being named after a corresponding msi + irq vector allocated to that device. -What: /sys/bus/pci/devices/.../msi_irqs//mode +What: /sys/bus/pci/devices/.../msi_irqs/ Date: September 2011 Contact: Neil Horman Description: This attribute indicates the mode that the irq vector named by - the parent directory is in (msi vs. msix) + the file is in (msi vs. msix) What: /sys/bus/pci/devices/.../remove Date: January 2009 diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 3fcd67a16677..f88fa1277802 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -363,6 +363,9 @@ void write_msi_msg(unsigned int irq, struct msi_msg *msg) static void free_msi_irqs(struct pci_dev *dev) { struct msi_desc *entry, *tmp; + struct attribute **msi_attrs; + struct device_attribute *dev_attr; + int count = 0; list_for_each_entry(entry, &dev->msi_list, list) { int i, nvec; @@ -398,6 +401,22 @@ static void free_msi_irqs(struct pci_dev *dev) list_del(&entry->list); kfree(entry); } + + if (dev->msi_irq_groups) { + sysfs_remove_groups(&dev->dev.kobj, dev->msi_irq_groups); + msi_attrs = dev->msi_irq_groups[0]->attrs; + list_for_each_entry(entry, &dev->msi_list, list) { + dev_attr = container_of(msi_attrs[count], + struct device_attribute, attr); + kfree(dev_attr->attr.name); + kfree(dev_attr); + ++count; + } + kfree(msi_attrs); + kfree(dev->msi_irq_groups[0]); + kfree(dev->msi_irq_groups); + dev->msi_irq_groups = NULL; + } } static struct msi_desc *alloc_msi_entry(struct pci_dev *dev) @@ -471,94 +490,95 @@ void pci_restore_msi_state(struct pci_dev *dev) } EXPORT_SYMBOL_GPL(pci_restore_msi_state); - -#define to_msi_attr(obj) container_of(obj, struct msi_attribute, attr) -#define to_msi_desc(obj) container_of(obj, struct msi_desc, kobj) - -struct msi_attribute { - struct attribute attr; - ssize_t (*show)(struct msi_desc *entry, struct msi_attribute *attr, - char *buf); - ssize_t (*store)(struct msi_desc *entry, struct msi_attribute *attr, - const char *buf, size_t count); -}; - -static ssize_t show_msi_mode(struct msi_desc *entry, struct msi_attribute *atr, +static ssize_t msi_mode_show(struct device *dev, struct device_attribute *attr, char *buf) { - return sprintf(buf, "%s\n", entry->msi_attrib.is_msix ? "msix" : "msi"); -} - -static ssize_t msi_irq_attr_show(struct kobject *kobj, - struct attribute *attr, char *buf) -{ - struct msi_attribute *attribute = to_msi_attr(attr); - struct msi_desc *entry = to_msi_desc(kobj); - - if (!attribute->show) - return -EIO; - - return attribute->show(entry, attribute, buf); -} - -static const struct sysfs_ops msi_irq_sysfs_ops = { - .show = msi_irq_attr_show, -}; - -static struct msi_attribute mode_attribute = - __ATTR(mode, S_IRUGO, show_msi_mode, NULL); - - -static struct attribute *msi_irq_default_attrs[] = { - &mode_attribute.attr, - NULL -}; + struct pci_dev *pdev = to_pci_dev(dev); + struct msi_desc *entry; + unsigned long irq; + int retval; -static void msi_kobj_release(struct kobject *kobj) -{ - struct msi_desc *entry = to_msi_desc(kobj); + retval = kstrtoul(attr->attr.name, 10, &irq); + if (retval) + return retval; - pci_dev_put(entry->dev); + list_for_each_entry(entry, &pdev->msi_list, list) { + if (entry->irq == irq) { + return sprintf(buf, "%s\n", + entry->msi_attrib.is_msix ? "msix" : "msi"); + } + } + return -ENODEV; } -static struct kobj_type msi_irq_ktype = { - .release = msi_kobj_release, - .sysfs_ops = &msi_irq_sysfs_ops, - .default_attrs = msi_irq_default_attrs, -}; - static int populate_msi_sysfs(struct pci_dev *pdev) { + struct attribute **msi_attrs; + struct attribute *msi_attr; + struct device_attribute *msi_dev_attr; + struct attribute_group *msi_irq_group; + const struct attribute_group **msi_irq_groups; struct msi_desc *entry; - struct kobject *kobj; - int ret; + int ret = -ENOMEM; + int num_msi = 0; int count = 0; - pdev->msi_kset = kset_create_and_add("msi_irqs", NULL, &pdev->dev.kobj); - if (!pdev->msi_kset) - return -ENOMEM; + /* Determine how many msi entries we have */ + list_for_each_entry(entry, &pdev->msi_list, list) { + ++num_msi; + } + if (!num_msi) + return 0; + /* Dynamically create the MSI attributes for the PCI device */ + msi_attrs = kzalloc(sizeof(void *) * (num_msi + 1), GFP_KERNEL); + if (!msi_attrs) + return -ENOMEM; list_for_each_entry(entry, &pdev->msi_list, list) { - kobj = &entry->kobj; - kobj->kset = pdev->msi_kset; - pci_dev_get(pdev); - ret = kobject_init_and_add(kobj, &msi_irq_ktype, NULL, - "%u", entry->irq); - if (ret) - goto out_unroll; - - count++; + char *name = kmalloc(20, GFP_KERNEL); + msi_dev_attr = kzalloc(sizeof(*msi_dev_attr), GFP_KERNEL); + if (!msi_dev_attr) + goto error_attrs; + sprintf(name, "%d", entry->irq); + sysfs_attr_init(&msi_dev_attr->attr); + msi_dev_attr->attr.name = name; + msi_dev_attr->attr.mode = S_IRUGO; + msi_dev_attr->show = msi_mode_show; + msi_attrs[count] = &msi_dev_attr->attr; + ++count; } + msi_irq_group = kzalloc(sizeof(*msi_irq_group), GFP_KERNEL); + if (!msi_irq_group) + goto error_attrs; + msi_irq_group->name = "msi_irqs"; + msi_irq_group->attrs = msi_attrs; + + msi_irq_groups = kzalloc(sizeof(void *) * 2, GFP_KERNEL); + if (!msi_irq_groups) + goto error_irq_group; + msi_irq_groups[0] = msi_irq_group; + + ret = sysfs_create_groups(&pdev->dev.kobj, msi_irq_groups); + if (ret) + goto error_irq_groups; + pdev->msi_irq_groups = msi_irq_groups; + return 0; -out_unroll: - list_for_each_entry(entry, &pdev->msi_list, list) { - if (!count) - break; - kobject_del(&entry->kobj); - kobject_put(&entry->kobj); - count--; +error_irq_groups: + kfree(msi_irq_groups); +error_irq_group: + kfree(msi_irq_group); +error_attrs: + count = 0; + msi_attr = msi_attrs[count]; + while (msi_attr) { + msi_dev_attr = container_of(msi_attr, struct device_attribute, attr); + kfree(msi_attr->name); + kfree(msi_dev_attr); + ++count; + msi_attr = msi_attrs[count]; } return ret; } @@ -925,8 +945,6 @@ void pci_disable_msi(struct pci_dev *dev) pci_msi_shutdown(dev); free_msi_irqs(dev); - kset_unregister(dev->msi_kset); - dev->msi_kset = NULL; } EXPORT_SYMBOL(pci_disable_msi); @@ -1023,8 +1041,6 @@ void pci_disable_msix(struct pci_dev *dev) pci_msix_shutdown(dev); free_msi_irqs(dev); - kset_unregister(dev->msi_kset); - dev->msi_kset = NULL; } EXPORT_SYMBOL(pci_disable_msix); diff --git a/include/linux/pci.h b/include/linux/pci.h index 1084a15175e0..36a5b1828f91 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -351,7 +351,7 @@ struct pci_dev { struct bin_attribute *res_attr_wc[DEVICE_COUNT_RESOURCE]; /* sysfs file for WC mapping of resources */ #ifdef CONFIG_PCI_MSI struct list_head msi_list; - struct kset *msi_kset; + const struct attribute_group **msi_irq_groups; #endif struct pci_vpd *vpd; #ifdef CONFIG_PCI_ATS -- 2.20.1