linux/kernel/irq/msi.c
Thomas Gleixner 74a5257a0c genirq/msi: Populate sysfs entry only once
The MSI entries for multi-MSI are populated en bloc for the MSI descriptor,
but the current code invokes the population inside the per interrupt loop
which triggers a warning in the sysfs code and causes the interrupt
allocation to fail.

Move it outside of the loop so it works correctly for single and multi-MSI.

Fixes: bf5e758f02 ("genirq/msi: Simplify sysfs handling")
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/87leznqx2a.ffs@tglx
2022-01-10 19:22:10 +01:00

1038 lines
27 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2014 Intel Corp.
* Author: Jiang Liu <jiang.liu@linux.intel.com>
*
* This file is licensed under GPLv2.
*
* This file contains common code to support Message Signaled Interrupts for
* PCI compatible and non PCI compatible devices.
*/
#include <linux/types.h>
#include <linux/device.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/msi.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/pci.h>
#include "internals.h"
static inline int msi_sysfs_create_group(struct device *dev);
/**
* msi_alloc_desc - Allocate an initialized msi_desc
* @dev: Pointer to the device for which this is allocated
* @nvec: The number of vectors used in this entry
* @affinity: Optional pointer to an affinity mask array size of @nvec
*
* If @affinity is not %NULL then an affinity array[@nvec] is allocated
* and the affinity masks and flags from @affinity are copied.
*
* Return: pointer to allocated &msi_desc on success or %NULL on failure
*/
static struct msi_desc *msi_alloc_desc(struct device *dev, int nvec,
const struct irq_affinity_desc *affinity)
{
struct msi_desc *desc = kzalloc(sizeof(*desc), GFP_KERNEL);
if (!desc)
return NULL;
desc->dev = dev;
desc->nvec_used = nvec;
if (affinity) {
desc->affinity = kmemdup(affinity, nvec * sizeof(*desc->affinity), GFP_KERNEL);
if (!desc->affinity) {
kfree(desc);
return NULL;
}
}
return desc;
}
static void msi_free_desc(struct msi_desc *desc)
{
kfree(desc->affinity);
kfree(desc);
}
static int msi_insert_desc(struct msi_device_data *md, struct msi_desc *desc, unsigned int index)
{
int ret;
desc->msi_index = index;
ret = xa_insert(&md->__store, index, desc, GFP_KERNEL);
if (ret)
msi_free_desc(desc);
return ret;
}
/**
* msi_add_msi_desc - Allocate and initialize a MSI descriptor
* @dev: Pointer to the device for which the descriptor is allocated
* @init_desc: Pointer to an MSI descriptor to initialize the new descriptor
*
* Return: 0 on success or an appropriate failure code.
*/
int msi_add_msi_desc(struct device *dev, struct msi_desc *init_desc)
{
struct msi_desc *desc;
lockdep_assert_held(&dev->msi.data->mutex);
desc = msi_alloc_desc(dev, init_desc->nvec_used, init_desc->affinity);
if (!desc)
return -ENOMEM;
/* Copy type specific data to the new descriptor. */
desc->pci = init_desc->pci;
return msi_insert_desc(dev->msi.data, desc, init_desc->msi_index);
}
/**
* msi_add_simple_msi_descs - Allocate and initialize MSI descriptors
* @dev: Pointer to the device for which the descriptors are allocated
* @index: Index for the first MSI descriptor
* @ndesc: Number of descriptors to allocate
*
* Return: 0 on success or an appropriate failure code.
*/
static int msi_add_simple_msi_descs(struct device *dev, unsigned int index, unsigned int ndesc)
{
unsigned int idx, last = index + ndesc - 1;
struct msi_desc *desc;
int ret;
lockdep_assert_held(&dev->msi.data->mutex);
for (idx = index; idx <= last; idx++) {
desc = msi_alloc_desc(dev, 1, NULL);
if (!desc)
goto fail_mem;
ret = msi_insert_desc(dev->msi.data, desc, idx);
if (ret)
goto fail;
}
return 0;
fail_mem:
ret = -ENOMEM;
fail:
msi_free_msi_descs_range(dev, MSI_DESC_NOTASSOCIATED, index, last);
return ret;
}
static bool msi_desc_match(struct msi_desc *desc, enum msi_desc_filter filter)
{
switch (filter) {
case MSI_DESC_ALL:
return true;
case MSI_DESC_NOTASSOCIATED:
return !desc->irq;
case MSI_DESC_ASSOCIATED:
return !!desc->irq;
}
WARN_ON_ONCE(1);
return false;
}
/**
* msi_free_msi_descs_range - Free MSI descriptors of a device
* @dev: Device to free the descriptors
* @filter: Descriptor state filter
* @first_index: Index to start freeing from
* @last_index: Last index to be freed
*/
void msi_free_msi_descs_range(struct device *dev, enum msi_desc_filter filter,
unsigned int first_index, unsigned int last_index)
{
struct xarray *xa = &dev->msi.data->__store;
struct msi_desc *desc;
unsigned long idx;
lockdep_assert_held(&dev->msi.data->mutex);
xa_for_each_range(xa, idx, desc, first_index, last_index) {
if (msi_desc_match(desc, filter)) {
xa_erase(xa, idx);
msi_free_desc(desc);
}
}
}
void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
{
*msg = entry->msg;
}
void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg)
{
struct msi_desc *entry = irq_get_msi_desc(irq);
__get_cached_msi_msg(entry, msg);
}
EXPORT_SYMBOL_GPL(get_cached_msi_msg);
static void msi_device_data_release(struct device *dev, void *res)
{
struct msi_device_data *md = res;
WARN_ON_ONCE(!xa_empty(&md->__store));
xa_destroy(&md->__store);
dev->msi.data = NULL;
}
/**
* msi_setup_device_data - Setup MSI device data
* @dev: Device for which MSI device data should be set up
*
* Return: 0 on success, appropriate error code otherwise
*
* This can be called more than once for @dev. If the MSI device data is
* already allocated the call succeeds. The allocated memory is
* automatically released when the device is destroyed.
*/
int msi_setup_device_data(struct device *dev)
{
struct msi_device_data *md;
int ret;
if (dev->msi.data)
return 0;
md = devres_alloc(msi_device_data_release, sizeof(*md), GFP_KERNEL);
if (!md)
return -ENOMEM;
ret = msi_sysfs_create_group(dev);
if (ret) {
devres_free(md);
return ret;
}
xa_init(&md->__store);
mutex_init(&md->mutex);
dev->msi.data = md;
devres_add(dev, md);
return 0;
}
/**
* msi_lock_descs - Lock the MSI descriptor storage of a device
* @dev: Device to operate on
*/
void msi_lock_descs(struct device *dev)
{
mutex_lock(&dev->msi.data->mutex);
}
EXPORT_SYMBOL_GPL(msi_lock_descs);
/**
* msi_unlock_descs - Unlock the MSI descriptor storage of a device
* @dev: Device to operate on
*/
void msi_unlock_descs(struct device *dev)
{
/* Invalidate the index wich was cached by the iterator */
dev->msi.data->__iter_idx = MSI_MAX_INDEX;
mutex_unlock(&dev->msi.data->mutex);
}
EXPORT_SYMBOL_GPL(msi_unlock_descs);
static struct msi_desc *msi_find_desc(struct msi_device_data *md, enum msi_desc_filter filter)
{
struct msi_desc *desc;
xa_for_each_start(&md->__store, md->__iter_idx, desc, md->__iter_idx) {
if (msi_desc_match(desc, filter))
return desc;
}
md->__iter_idx = MSI_MAX_INDEX;
return NULL;
}
/**
* msi_first_desc - Get the first MSI descriptor of a device
* @dev: Device to operate on
* @filter: Descriptor state filter
*
* Must be called with the MSI descriptor mutex held, i.e. msi_lock_descs()
* must be invoked before the call.
*
* Return: Pointer to the first MSI descriptor matching the search
* criteria, NULL if none found.
*/
struct msi_desc *msi_first_desc(struct device *dev, enum msi_desc_filter filter)
{
struct msi_device_data *md = dev->msi.data;
if (WARN_ON_ONCE(!md))
return NULL;
lockdep_assert_held(&md->mutex);
md->__iter_idx = 0;
return msi_find_desc(md, filter);
}
EXPORT_SYMBOL_GPL(msi_first_desc);
/**
* msi_next_desc - Get the next MSI descriptor of a device
* @dev: Device to operate on
*
* The first invocation of msi_next_desc() has to be preceeded by a
* successful invocation of __msi_first_desc(). Consecutive invocations are
* only valid if the previous one was successful. All these operations have
* to be done within the same MSI mutex held region.
*
* Return: Pointer to the next MSI descriptor matching the search
* criteria, NULL if none found.
*/
struct msi_desc *msi_next_desc(struct device *dev, enum msi_desc_filter filter)
{
struct msi_device_data *md = dev->msi.data;
if (WARN_ON_ONCE(!md))
return NULL;
lockdep_assert_held(&md->mutex);
if (md->__iter_idx >= (unsigned long)MSI_MAX_INDEX)
return NULL;
md->__iter_idx++;
return msi_find_desc(md, filter);
}
EXPORT_SYMBOL_GPL(msi_next_desc);
/**
* msi_get_virq - Return Linux interrupt number of a MSI interrupt
* @dev: Device to operate on
* @index: MSI interrupt index to look for (0-based)
*
* Return: The Linux interrupt number on success (> 0), 0 if not found
*/
unsigned int msi_get_virq(struct device *dev, unsigned int index)
{
struct msi_desc *desc;
unsigned int ret = 0;
bool pcimsi;
if (!dev->msi.data)
return 0;
pcimsi = dev_is_pci(dev) ? to_pci_dev(dev)->msi_enabled : false;
msi_lock_descs(dev);
desc = xa_load(&dev->msi.data->__store, pcimsi ? 0 : index);
if (desc && desc->irq) {
/*
* PCI-MSI has only one descriptor for multiple interrupts.
* PCI-MSIX and platform MSI use a descriptor per
* interrupt.
*/
if (pcimsi) {
if (index < desc->nvec_used)
ret = desc->irq + index;
} else {
ret = desc->irq;
}
}
msi_unlock_descs(dev);
return ret;
}
EXPORT_SYMBOL_GPL(msi_get_virq);
#ifdef CONFIG_SYSFS
static struct attribute *msi_dev_attrs[] = {
NULL
};
static const struct attribute_group msi_irqs_group = {
.name = "msi_irqs",
.attrs = msi_dev_attrs,
};
static inline int msi_sysfs_create_group(struct device *dev)
{
return devm_device_add_group(dev, &msi_irqs_group);
}
static ssize_t msi_mode_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
/* MSI vs. MSIX is per device not per interrupt */
bool is_msix = dev_is_pci(dev) ? to_pci_dev(dev)->msix_enabled : false;
return sysfs_emit(buf, "%s\n", is_msix ? "msix" : "msi");
}
static void msi_sysfs_remove_desc(struct device *dev, struct msi_desc *desc)
{
struct device_attribute *attrs = desc->sysfs_attrs;
int i;
if (!attrs)
return;
desc->sysfs_attrs = NULL;
for (i = 0; i < desc->nvec_used; i++) {
if (attrs[i].show)
sysfs_remove_file_from_group(&dev->kobj, &attrs[i].attr, msi_irqs_group.name);
kfree(attrs[i].attr.name);
}
kfree(attrs);
}
static int msi_sysfs_populate_desc(struct device *dev, struct msi_desc *desc)
{
struct device_attribute *attrs;
int ret, i;
attrs = kcalloc(desc->nvec_used, sizeof(*attrs), GFP_KERNEL);
if (!attrs)
return -ENOMEM;
desc->sysfs_attrs = attrs;
for (i = 0; i < desc->nvec_used; i++) {
sysfs_attr_init(&attrs[i].attr);
attrs[i].attr.name = kasprintf(GFP_KERNEL, "%d", desc->irq + i);
if (!attrs[i].attr.name) {
ret = -ENOMEM;
goto fail;
}
attrs[i].attr.mode = 0444;
attrs[i].show = msi_mode_show;
ret = sysfs_add_file_to_group(&dev->kobj, &attrs[i].attr, msi_irqs_group.name);
if (ret) {
attrs[i].show = NULL;
goto fail;
}
}
return 0;
fail:
msi_sysfs_remove_desc(dev, desc);
return ret;
}
#ifdef CONFIG_PCI_MSI_ARCH_FALLBACKS
/**
* msi_device_populate_sysfs - Populate msi_irqs sysfs entries for a device
* @dev: The device (PCI, platform etc) which will get sysfs entries
*/
int msi_device_populate_sysfs(struct device *dev)
{
struct msi_desc *desc;
int ret;
msi_for_each_desc(desc, dev, MSI_DESC_ASSOCIATED) {
if (desc->sysfs_attrs)
continue;
ret = msi_sysfs_populate_desc(dev, desc);
if (ret)
return ret;
}
return 0;
}
/**
* msi_device_destroy_sysfs - Destroy msi_irqs sysfs entries for a device
* @dev: The device (PCI, platform etc) for which to remove
* sysfs entries
*/
void msi_device_destroy_sysfs(struct device *dev)
{
struct msi_desc *desc;
msi_for_each_desc(desc, dev, MSI_DESC_ALL)
msi_sysfs_remove_desc(dev, desc);
}
#endif /* CONFIG_PCI_MSI_ARCH_FALLBACK */
#else /* CONFIG_SYSFS */
static inline int msi_sysfs_create_group(struct device *dev) { return 0; }
static inline int msi_sysfs_populate_desc(struct device *dev, struct msi_desc *desc) { return 0; }
static inline void msi_sysfs_remove_desc(struct device *dev, struct msi_desc *desc) { }
#endif /* !CONFIG_SYSFS */
#ifdef CONFIG_GENERIC_MSI_IRQ_DOMAIN
static inline void irq_chip_write_msi_msg(struct irq_data *data,
struct msi_msg *msg)
{
data->chip->irq_write_msi_msg(data, msg);
}
static void msi_check_level(struct irq_domain *domain, struct msi_msg *msg)
{
struct msi_domain_info *info = domain->host_data;
/*
* If the MSI provider has messed with the second message and
* not advertized that it is level-capable, signal the breakage.
*/
WARN_ON(!((info->flags & MSI_FLAG_LEVEL_CAPABLE) &&
(info->chip->flags & IRQCHIP_SUPPORTS_LEVEL_MSI)) &&
(msg[1].address_lo || msg[1].address_hi || msg[1].data));
}
/**
* msi_domain_set_affinity - Generic affinity setter function for MSI domains
* @irq_data: The irq data associated to the interrupt
* @mask: The affinity mask to set
* @force: Flag to enforce setting (disable online checks)
*
* Intended to be used by MSI interrupt controllers which are
* implemented with hierarchical domains.
*
* Return: IRQ_SET_MASK_* result code
*/
int msi_domain_set_affinity(struct irq_data *irq_data,
const struct cpumask *mask, bool force)
{
struct irq_data *parent = irq_data->parent_data;
struct msi_msg msg[2] = { [1] = { }, };
int ret;
ret = parent->chip->irq_set_affinity(parent, mask, force);
if (ret >= 0 && ret != IRQ_SET_MASK_OK_DONE) {
BUG_ON(irq_chip_compose_msi_msg(irq_data, msg));
msi_check_level(irq_data->domain, msg);
irq_chip_write_msi_msg(irq_data, msg);
}
return ret;
}
static int msi_domain_activate(struct irq_domain *domain,
struct irq_data *irq_data, bool early)
{
struct msi_msg msg[2] = { [1] = { }, };
BUG_ON(irq_chip_compose_msi_msg(irq_data, msg));
msi_check_level(irq_data->domain, msg);
irq_chip_write_msi_msg(irq_data, msg);
return 0;
}
static void msi_domain_deactivate(struct irq_domain *domain,
struct irq_data *irq_data)
{
struct msi_msg msg[2];
memset(msg, 0, sizeof(msg));
irq_chip_write_msi_msg(irq_data, msg);
}
static int msi_domain_alloc(struct irq_domain *domain, unsigned int virq,
unsigned int nr_irqs, void *arg)
{
struct msi_domain_info *info = domain->host_data;
struct msi_domain_ops *ops = info->ops;
irq_hw_number_t hwirq = ops->get_hwirq(info, arg);
int i, ret;
if (irq_find_mapping(domain, hwirq) > 0)
return -EEXIST;
if (domain->parent) {
ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg);
if (ret < 0)
return ret;
}
for (i = 0; i < nr_irqs; i++) {
ret = ops->msi_init(domain, info, virq + i, hwirq + i, arg);
if (ret < 0) {
if (ops->msi_free) {
for (i--; i > 0; i--)
ops->msi_free(domain, info, virq + i);
}
irq_domain_free_irqs_top(domain, virq, nr_irqs);
return ret;
}
}
return 0;
}
static void msi_domain_free(struct irq_domain *domain, unsigned int virq,
unsigned int nr_irqs)
{
struct msi_domain_info *info = domain->host_data;
int i;
if (info->ops->msi_free) {
for (i = 0; i < nr_irqs; i++)
info->ops->msi_free(domain, info, virq + i);
}
irq_domain_free_irqs_top(domain, virq, nr_irqs);
}
static const struct irq_domain_ops msi_domain_ops = {
.alloc = msi_domain_alloc,
.free = msi_domain_free,
.activate = msi_domain_activate,
.deactivate = msi_domain_deactivate,
};
static irq_hw_number_t msi_domain_ops_get_hwirq(struct msi_domain_info *info,
msi_alloc_info_t *arg)
{
return arg->hwirq;
}
static int msi_domain_ops_prepare(struct irq_domain *domain, struct device *dev,
int nvec, msi_alloc_info_t *arg)
{
memset(arg, 0, sizeof(*arg));
return 0;
}
static void msi_domain_ops_set_desc(msi_alloc_info_t *arg,
struct msi_desc *desc)
{
arg->desc = desc;
}
static int msi_domain_ops_init(struct irq_domain *domain,
struct msi_domain_info *info,
unsigned int virq, irq_hw_number_t hwirq,
msi_alloc_info_t *arg)
{
irq_domain_set_hwirq_and_chip(domain, virq, hwirq, info->chip,
info->chip_data);
if (info->handler && info->handler_name) {
__irq_set_handler(virq, info->handler, 0, info->handler_name);
if (info->handler_data)
irq_set_handler_data(virq, info->handler_data);
}
return 0;
}
static int msi_domain_ops_check(struct irq_domain *domain,
struct msi_domain_info *info,
struct device *dev)
{
return 0;
}
static struct msi_domain_ops msi_domain_ops_default = {
.get_hwirq = msi_domain_ops_get_hwirq,
.msi_init = msi_domain_ops_init,
.msi_check = msi_domain_ops_check,
.msi_prepare = msi_domain_ops_prepare,
.set_desc = msi_domain_ops_set_desc,
.domain_alloc_irqs = __msi_domain_alloc_irqs,
.domain_free_irqs = __msi_domain_free_irqs,
};
static void msi_domain_update_dom_ops(struct msi_domain_info *info)
{
struct msi_domain_ops *ops = info->ops;
if (ops == NULL) {
info->ops = &msi_domain_ops_default;
return;
}
if (ops->domain_alloc_irqs == NULL)
ops->domain_alloc_irqs = msi_domain_ops_default.domain_alloc_irqs;
if (ops->domain_free_irqs == NULL)
ops->domain_free_irqs = msi_domain_ops_default.domain_free_irqs;
if (!(info->flags & MSI_FLAG_USE_DEF_DOM_OPS))
return;
if (ops->get_hwirq == NULL)
ops->get_hwirq = msi_domain_ops_default.get_hwirq;
if (ops->msi_init == NULL)
ops->msi_init = msi_domain_ops_default.msi_init;
if (ops->msi_check == NULL)
ops->msi_check = msi_domain_ops_default.msi_check;
if (ops->msi_prepare == NULL)
ops->msi_prepare = msi_domain_ops_default.msi_prepare;
if (ops->set_desc == NULL)
ops->set_desc = msi_domain_ops_default.set_desc;
}
static void msi_domain_update_chip_ops(struct msi_domain_info *info)
{
struct irq_chip *chip = info->chip;
BUG_ON(!chip || !chip->irq_mask || !chip->irq_unmask);
if (!chip->irq_set_affinity)
chip->irq_set_affinity = msi_domain_set_affinity;
}
/**
* msi_create_irq_domain - Create an MSI interrupt domain
* @fwnode: Optional fwnode of the interrupt controller
* @info: MSI domain info
* @parent: Parent irq domain
*
* Return: pointer to the created &struct irq_domain or %NULL on failure
*/
struct irq_domain *msi_create_irq_domain(struct fwnode_handle *fwnode,
struct msi_domain_info *info,
struct irq_domain *parent)
{
struct irq_domain *domain;
msi_domain_update_dom_ops(info);
if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
msi_domain_update_chip_ops(info);
domain = irq_domain_create_hierarchy(parent, IRQ_DOMAIN_FLAG_MSI, 0,
fwnode, &msi_domain_ops, info);
if (domain && !domain->name && info->chip)
domain->name = info->chip->name;
return domain;
}
int msi_domain_prepare_irqs(struct irq_domain *domain, struct device *dev,
int nvec, msi_alloc_info_t *arg)
{
struct msi_domain_info *info = domain->host_data;
struct msi_domain_ops *ops = info->ops;
int ret;
ret = ops->msi_check(domain, info, dev);
if (ret == 0)
ret = ops->msi_prepare(domain, dev, nvec, arg);
return ret;
}
int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev,
int virq_base, int nvec, msi_alloc_info_t *arg)
{
struct msi_domain_info *info = domain->host_data;
struct msi_domain_ops *ops = info->ops;
struct msi_desc *desc;
int ret, virq;
msi_lock_descs(dev);
ret = msi_add_simple_msi_descs(dev, virq_base, nvec);
if (ret)
goto unlock;
for (virq = virq_base; virq < virq_base + nvec; virq++) {
desc = xa_load(&dev->msi.data->__store, virq);
desc->irq = virq;
ops->set_desc(arg, desc);
ret = irq_domain_alloc_irqs_hierarchy(domain, virq, 1, arg);
if (ret)
goto fail;
irq_set_msi_desc(virq, desc);
}
msi_unlock_descs(dev);
return 0;
fail:
for (--virq; virq >= virq_base; virq--)
irq_domain_free_irqs_common(domain, virq, 1);
msi_free_msi_descs_range(dev, MSI_DESC_ALL, virq_base, virq_base + nvec - 1);
unlock:
msi_unlock_descs(dev);
return ret;
}
/*
* Carefully check whether the device can use reservation mode. If
* reservation mode is enabled then the early activation will assign a
* dummy vector to the device. If the PCI/MSI device does not support
* masking of the entry then this can result in spurious interrupts when
* the device driver is not absolutely careful. But even then a malfunction
* of the hardware could result in a spurious interrupt on the dummy vector
* and render the device unusable. If the entry can be masked then the core
* logic will prevent the spurious interrupt and reservation mode can be
* used. For now reservation mode is restricted to PCI/MSI.
*/
static bool msi_check_reservation_mode(struct irq_domain *domain,
struct msi_domain_info *info,
struct device *dev)
{
struct msi_desc *desc;
switch(domain->bus_token) {
case DOMAIN_BUS_PCI_MSI:
case DOMAIN_BUS_VMD_MSI:
break;
default:
return false;
}
if (!(info->flags & MSI_FLAG_MUST_REACTIVATE))
return false;
if (IS_ENABLED(CONFIG_PCI_MSI) && pci_msi_ignore_mask)
return false;
/*
* Checking the first MSI descriptor is sufficient. MSIX supports
* masking and MSI does so when the can_mask attribute is set.
*/
desc = msi_first_desc(dev, MSI_DESC_ALL);
return desc->pci.msi_attrib.is_msix || desc->pci.msi_attrib.can_mask;
}
static int msi_handle_pci_fail(struct irq_domain *domain, struct msi_desc *desc,
int allocated)
{
switch(domain->bus_token) {
case DOMAIN_BUS_PCI_MSI:
case DOMAIN_BUS_VMD_MSI:
if (IS_ENABLED(CONFIG_PCI_MSI))
break;
fallthrough;
default:
return -ENOSPC;
}
/* Let a failed PCI multi MSI allocation retry */
if (desc->nvec_used > 1)
return 1;
/* If there was a successful allocation let the caller know */
return allocated ? allocated : -ENOSPC;
}
#define VIRQ_CAN_RESERVE 0x01
#define VIRQ_ACTIVATE 0x02
#define VIRQ_NOMASK_QUIRK 0x04
static int msi_init_virq(struct irq_domain *domain, int virq, unsigned int vflags)
{
struct irq_data *irqd = irq_domain_get_irq_data(domain, virq);
int ret;
if (!(vflags & VIRQ_CAN_RESERVE)) {
irqd_clr_can_reserve(irqd);
if (vflags & VIRQ_NOMASK_QUIRK)
irqd_set_msi_nomask_quirk(irqd);
}
if (!(vflags & VIRQ_ACTIVATE))
return 0;
ret = irq_domain_activate_irq(irqd, vflags & VIRQ_CAN_RESERVE);
if (ret)
return ret;
/*
* If the interrupt uses reservation mode, clear the activated bit
* so request_irq() will assign the final vector.
*/
if (vflags & VIRQ_CAN_RESERVE)
irqd_clr_activated(irqd);
return 0;
}
int __msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
int nvec)
{
struct msi_domain_info *info = domain->host_data;
struct msi_domain_ops *ops = info->ops;
msi_alloc_info_t arg = { };
unsigned int vflags = 0;
struct msi_desc *desc;
int allocated = 0;
int i, ret, virq;
ret = msi_domain_prepare_irqs(domain, dev, nvec, &arg);
if (ret)
return ret;
/*
* This flag is set by the PCI layer as we need to activate
* the MSI entries before the PCI layer enables MSI in the
* card. Otherwise the card latches a random msi message.
*/
if (info->flags & MSI_FLAG_ACTIVATE_EARLY)
vflags |= VIRQ_ACTIVATE;
/*
* Interrupt can use a reserved vector and will not occupy
* a real device vector until the interrupt is requested.
*/
if (msi_check_reservation_mode(domain, info, dev)) {
vflags |= VIRQ_CAN_RESERVE;
/*
* MSI affinity setting requires a special quirk (X86) when
* reservation mode is active.
*/
if (domain->flags & IRQ_DOMAIN_MSI_NOMASK_QUIRK)
vflags |= VIRQ_NOMASK_QUIRK;
}
msi_for_each_desc(desc, dev, MSI_DESC_NOTASSOCIATED) {
ops->set_desc(&arg, desc);
virq = __irq_domain_alloc_irqs(domain, -1, desc->nvec_used,
dev_to_node(dev), &arg, false,
desc->affinity);
if (virq < 0)
return msi_handle_pci_fail(domain, desc, allocated);
for (i = 0; i < desc->nvec_used; i++) {
irq_set_msi_desc_off(virq, i, desc);
irq_debugfs_copy_devname(virq + i, dev);
ret = msi_init_virq(domain, virq + i, vflags);
if (ret)
return ret;
}
if (info->flags & MSI_FLAG_DEV_SYSFS) {
ret = msi_sysfs_populate_desc(dev, desc);
if (ret)
return ret;
}
allocated++;
}
return 0;
}
static int msi_domain_add_simple_msi_descs(struct msi_domain_info *info,
struct device *dev,
unsigned int num_descs)
{
if (!(info->flags & MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS))
return 0;
return msi_add_simple_msi_descs(dev, 0, num_descs);
}
/**
* msi_domain_alloc_irqs_descs_locked - Allocate interrupts from a MSI interrupt domain
* @domain: The domain to allocate from
* @dev: Pointer to device struct of the device for which the interrupts
* are allocated
* @nvec: The number of interrupts to allocate
*
* Must be invoked from within a msi_lock_descs() / msi_unlock_descs()
* pair. Use this for MSI irqdomains which implement their own vector
* allocation/free.
*
* Return: %0 on success or an error code.
*/
int msi_domain_alloc_irqs_descs_locked(struct irq_domain *domain, struct device *dev,
int nvec)
{
struct msi_domain_info *info = domain->host_data;
struct msi_domain_ops *ops = info->ops;
int ret;
lockdep_assert_held(&dev->msi.data->mutex);
ret = msi_domain_add_simple_msi_descs(info, dev, nvec);
if (ret)
return ret;
ret = ops->domain_alloc_irqs(domain, dev, nvec);
if (ret)
msi_domain_free_irqs_descs_locked(domain, dev);
return ret;
}
/**
* msi_domain_alloc_irqs - Allocate interrupts from a MSI interrupt domain
* @domain: The domain to allocate from
* @dev: Pointer to device struct of the device for which the interrupts
* are allocated
* @nvec: The number of interrupts to allocate
*
* Return: %0 on success or an error code.
*/
int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev, int nvec)
{
int ret;
msi_lock_descs(dev);
ret = msi_domain_alloc_irqs_descs_locked(domain, dev, nvec);
msi_unlock_descs(dev);
return ret;
}
void __msi_domain_free_irqs(struct irq_domain *domain, struct device *dev)
{
struct msi_domain_info *info = domain->host_data;
struct irq_data *irqd;
struct msi_desc *desc;
int i;
/* Only handle MSI entries which have an interrupt associated */
msi_for_each_desc(desc, dev, MSI_DESC_ASSOCIATED) {
/* Make sure all interrupts are deactivated */
for (i = 0; i < desc->nvec_used; i++) {
irqd = irq_domain_get_irq_data(domain, desc->irq + i);
if (irqd && irqd_is_activated(irqd))
irq_domain_deactivate_irq(irqd);
}
irq_domain_free_irqs(desc->irq, desc->nvec_used);
if (info->flags & MSI_FLAG_DEV_SYSFS)
msi_sysfs_remove_desc(dev, desc);
desc->irq = 0;
}
}
static void msi_domain_free_msi_descs(struct msi_domain_info *info,
struct device *dev)
{
if (info->flags & MSI_FLAG_FREE_MSI_DESCS)
msi_free_msi_descs(dev);
}
/**
* msi_domain_free_irqs_descs_locked - Free interrupts 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 interrupts
* are free
*
* Must be invoked from within a msi_lock_descs() / msi_unlock_descs()
* pair. Use this for MSI irqdomains which implement their own vector
* allocation.
*/
void msi_domain_free_irqs_descs_locked(struct irq_domain *domain, struct device *dev)
{
struct msi_domain_info *info = domain->host_data;
struct msi_domain_ops *ops = info->ops;
lockdep_assert_held(&dev->msi.data->mutex);
ops->domain_free_irqs(domain, dev);
msi_domain_free_msi_descs(info, dev);
}
/**
* msi_domain_free_irqs - Free interrupts 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 interrupts
* are free
*/
void msi_domain_free_irqs(struct irq_domain *domain, struct device *dev)
{
msi_lock_descs(dev);
msi_domain_free_irqs_descs_locked(domain, dev);
msi_unlock_descs(dev);
}
/**
* msi_get_domain_info - Get the MSI interrupt domain info for @domain
* @domain: The interrupt domain to retrieve data from
*
* Return: the pointer to the msi_domain_info stored in @domain->host_data.
*/
struct msi_domain_info *msi_get_domain_info(struct irq_domain *domain)
{
return (struct msi_domain_info *)domain->host_data;
}
#endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */