Commit 2f170814 authored by Barry Song's avatar Barry Song Committed by Thomas Gleixner
Browse files

genirq/msi: Move MSI sysfs handling from PCI to MSI core 



Move PCI's MSI sysfs code to the irq core so that other busses such as
platform can reuse it.

Signed-off-by: default avatarBarry Song <song.bao.hua@hisilicon.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Acked-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Acked-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210813035628.6844-2-21cnbao@gmail.com
parent 88ffe2d0

drivers/pci/msi.c

+10 −115
Original line number Diff line number Diff line
@@ -363,9 +363,7 @@ static void free_msi_irqs(struct pci_dev *dev) 
{

	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, count = 0;

	int i;



	for_each_pci_msi_entry(entry, dev)

		if (entry->irq)
@@ -385,18 +383,7 @@ static void free_msi_irqs(struct pci_dev *dev) 
	}



	if (dev->msi_irq_groups) {

		sysfs_remove_groups(&dev->dev.kobj, dev->msi_irq_groups);

		msi_attrs = dev->msi_irq_groups[0]->attrs;

		while (msi_attrs[count]) {

			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);

		msi_destroy_sysfs(&dev->dev, dev->msi_irq_groups);

		dev->msi_irq_groups = NULL;

	}

}
@@ -476,102 +463,6 @@ void pci_restore_msi_state(struct pci_dev *dev) 
}

EXPORT_SYMBOL_GPL(pci_restore_msi_state);



static ssize_t msi_mode_show(struct device *dev, struct device_attribute *attr,

			     char *buf)

{

	struct msi_desc *entry;

	unsigned long irq;

	int retval;



	retval = kstrtoul(attr->attr.name, 10, &irq);

	if (retval)

		return retval;



	entry = irq_get_msi_desc(irq);

	if (!entry)

		return -ENODEV;



	return sysfs_emit(buf, "%s\n",

			  entry->msi_attrib.is_msix ? "msix" : "msi");

}



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;

	int ret = -ENOMEM;

	int num_msi = 0;

	int count = 0;

	int i;



	/* Determine how many msi entries we have */

	for_each_pci_msi_entry(entry, pdev)

		num_msi += entry->nvec_used;

	if (!num_msi)

		return 0;



	/* Dynamically create the MSI attributes for the PCI device */

	msi_attrs = kcalloc(num_msi + 1, sizeof(void *), GFP_KERNEL);

	if (!msi_attrs)

		return -ENOMEM;

	for_each_pci_msi_entry(entry, pdev) {

		for (i = 0; i < entry->nvec_used; i++) {

			msi_dev_attr = kzalloc(sizeof(*msi_dev_attr), GFP_KERNEL);

			if (!msi_dev_attr)

				goto error_attrs;

			msi_attrs[count] = &msi_dev_attr->attr;



			sysfs_attr_init(&msi_dev_attr->attr);

			msi_dev_attr->attr.name = kasprintf(GFP_KERNEL, "%d",

							    entry->irq + i);

			if (!msi_dev_attr->attr.name)

				goto error_attrs;

			msi_dev_attr->attr.mode = S_IRUGO;

			msi_dev_attr->show = msi_mode_show;

			++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 = kcalloc(2, sizeof(void *), 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;



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];

	}

	kfree(msi_attrs);

	return ret;

}



static struct msi_desc *

msi_setup_entry(struct pci_dev *dev, int nvec, struct irq_affinity *affd)

{
@@ -667,9 +558,11 @@ static int msi_capability_init(struct pci_dev *dev, int nvec, 
	if (ret)

		goto err;



	ret = populate_msi_sysfs(dev);

	if (ret)

	dev->msi_irq_groups = msi_populate_sysfs(&dev->dev);

	if (IS_ERR(dev->msi_irq_groups)) {

		ret = PTR_ERR(dev->msi_irq_groups);

		goto err;

	}



	/* Set MSI enabled bits	*/

	pci_intx_for_msi(dev, 0);
@@ -834,9 +727,11 @@ static int msix_capability_init(struct pci_dev *dev, struct msix_entry *entries, 


	msix_update_entries(dev, entries);



	ret = populate_msi_sysfs(dev);

	if (ret)

	dev->msi_irq_groups = msi_populate_sysfs(&dev->dev);

	if (IS_ERR(dev->msi_irq_groups)) {

		ret = PTR_ERR(dev->msi_irq_groups);

		goto out_free;

	}



	/* Set MSI-X enabled bits and unmask the function */

	pci_intx_for_msi(dev, 0);

include/linux/msi.h

+4 −0
Original line number Diff line number Diff line
@@ -239,6 +239,10 @@ void __pci_write_msi_msg(struct msi_desc *entry, struct msi_msg *msg); 
void pci_msi_mask_irq(struct irq_data *data);

void pci_msi_unmask_irq(struct irq_data *data);



const struct attribute_group **msi_populate_sysfs(struct device *dev);

void msi_destroy_sysfs(struct device *dev,

		       const struct attribute_group **msi_irq_groups);



/*

 * The arch hooks to setup up msi irqs. Default functions are implemented

 * as weak symbols so that they /can/ be overriden by architecture specific

kernel/irq/msi.c

+134 −0
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ 
#include <linux/irqdomain.h>

#include <linux/msi.h>

#include <linux/slab.h>

#include <linux/pci.h>



#include "internals.h"
@@ -71,6 +72,139 @@ void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg) 
}

EXPORT_SYMBOL_GPL(get_cached_msi_msg);



static ssize_t msi_mode_show(struct device *dev, struct device_attribute *attr,

			     char *buf)

{

	struct msi_desc *entry;

	bool is_msix = false;

	unsigned long irq;

	int retval;



	retval = kstrtoul(attr->attr.name, 10, &irq);

	if (retval)

		return retval;



	entry = irq_get_msi_desc(irq);

	if (!entry)

		return -ENODEV;



	if (dev_is_pci(dev))

		is_msix = entry->msi_attrib.is_msix;



	return sysfs_emit(buf, "%s\n", is_msix ? "msix" : "msi");

}



/**

 * msi_populate_sysfs - Populate msi_irqs sysfs entries for devices

 * @dev:	The device(PCI, platform etc) who will get sysfs entries

 *

 * Return attribute_group ** so that specific bus MSI can save it to

 * somewhere during initilizing msi irqs. If devices has no MSI irq,

 * return NULL; if it fails to populate sysfs, return ERR_PTR

 */

const struct attribute_group **msi_populate_sysfs(struct device *dev)

{

	const struct attribute_group **msi_irq_groups;

	struct attribute **msi_attrs, *msi_attr;

	struct device_attribute *msi_dev_attr;

	struct attribute_group *msi_irq_group;

	struct msi_desc *entry;

	int ret = -ENOMEM;

	int num_msi = 0;

	int count = 0;

	int i;



	/* Determine how many msi entries we have */

	for_each_msi_entry(entry, dev)

		num_msi += entry->nvec_used;

	if (!num_msi)

		return NULL;



	/* Dynamically create the MSI attributes for the device */

	msi_attrs = kcalloc(num_msi + 1, sizeof(void *), GFP_KERNEL);

	if (!msi_attrs)

		return ERR_PTR(-ENOMEM);



	for_each_msi_entry(entry, dev) {

		for (i = 0; i < entry->nvec_used; i++) {

			msi_dev_attr = kzalloc(sizeof(*msi_dev_attr), GFP_KERNEL);

			if (!msi_dev_attr)

				goto error_attrs;

			msi_attrs[count] = &msi_dev_attr->attr;



			sysfs_attr_init(&msi_dev_attr->attr);

			msi_dev_attr->attr.name = kasprintf(GFP_KERNEL, "%d",

							    entry->irq + i);

			if (!msi_dev_attr->attr.name)

				goto error_attrs;

			msi_dev_attr->attr.mode = 0444;

			msi_dev_attr->show = msi_mode_show;

			++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 = kcalloc(2, sizeof(void *), GFP_KERNEL);

	if (!msi_irq_groups)

		goto error_irq_group;

	msi_irq_groups[0] = msi_irq_group;



	ret = sysfs_create_groups(&dev->kobj, msi_irq_groups);

	if (ret)

		goto error_irq_groups;



	return msi_irq_groups;



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];

	}

	kfree(msi_attrs);

	return ERR_PTR(ret);

}



/**

 * msi_destroy_sysfs - Destroy msi_irqs sysfs entries for devices

 * @dev:		The device(PCI, platform etc) who will remove sysfs entries

 * @msi_irq_groups:	attribute_group for device msi_irqs entries

 */

void msi_destroy_sysfs(struct device *dev, const struct attribute_group **msi_irq_groups)

{

	struct device_attribute *dev_attr;

	struct attribute **msi_attrs;

	int count = 0;



	if (msi_irq_groups) {

		sysfs_remove_groups(&dev->kobj, msi_irq_groups);

		msi_attrs = msi_irq_groups[0]->attrs;

		while (msi_attrs[count]) {

			dev_attr = container_of(msi_attrs[count],

					struct device_attribute, attr);

			kfree(dev_attr->attr.name);

			kfree(dev_attr);

			++count;

		}

		kfree(msi_attrs);

		kfree(msi_irq_groups[0]);

		kfree(msi_irq_groups);

	}

}



#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN

static inline void irq_chip_write_msi_msg(struct irq_data *data,

					  struct msi_msg *msg)