linux/kernel/irq/msi.c
Linus Torvalds 4e9c542c7a A set of updates for the interrupt susbsystem:
- Prevent possible NULL pointer derefences in irq_data_get_affinity_mask()
     and irq_domain_create_hierarchy().
 
   - Take the per device MSI lock before invoking code which relies
     on it being hold.
 
   - Make sure that MSI descriptors are unreferenced before freeing
     them. This was overlooked when the platform MSI code was converted to
     use core infrastructure and results in a fals positive warning.
 
   - Remove dead code in the MSI subsystem.
 
   - Clarify the documentation for pci_msix_free_irq().
 
   - More kobj_type constification.
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Merge tag 'irq-urgent-2023-03-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq updates from Thomas Gleixner:
 "A set of updates for the interrupt susbsystem:

   - Prevent possible NULL pointer derefences in
     irq_data_get_affinity_mask() and irq_domain_create_hierarchy()

   - Take the per device MSI lock before invoking code which relies on
     it being hold

   - Make sure that MSI descriptors are unreferenced before freeing
     them. This was overlooked when the platform MSI code was converted
     to use core infrastructure and results in a fals positive warning

   - Remove dead code in the MSI subsystem

   - Clarify the documentation for pci_msix_free_irq()

   - More kobj_type constification"

* tag 'irq-urgent-2023-03-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/msi, platform-msi: Ensure that MSI descriptors are unreferenced
  genirq/msi: Drop dead domain name assignment
  irqdomain: Add missing NULL pointer check in irq_domain_create_hierarchy()
  genirq/irqdesc: Make kobj_type structures constant
  PCI/MSI: Clarify usage of pci_msix_free_irq()
  genirq/msi: Take the per-device MSI lock before validating the control structure
  genirq/ipi: Fix NULL pointer deref in irq_data_get_affinity_mask()
2023-03-05 11:19:16 -08:00

1678 lines
46 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"
/**
* struct msi_ctrl - MSI internal management control structure
* @domid: ID of the domain on which management operations should be done
* @first: First (hardware) slot index to operate on
* @last: Last (hardware) slot index to operate on
* @nirqs: The number of Linux interrupts to allocate. Can be larger
* than the range due to PCI/multi-MSI.
*/
struct msi_ctrl {
unsigned int domid;
unsigned int first;
unsigned int last;
unsigned int nirqs;
};
/* Invalid Xarray index which is outside of any searchable range */
#define MSI_XA_MAX_INDEX (ULONG_MAX - 1)
/* The maximum domain size */
#define MSI_XA_DOMAIN_SIZE (MSI_MAX_INDEX + 1)
static void msi_domain_free_locked(struct device *dev, struct msi_ctrl *ctrl);
static unsigned int msi_domain_get_hwsize(struct device *dev, unsigned int domid);
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 device *dev, struct msi_desc *desc,
unsigned int domid, unsigned int index)
{
struct msi_device_data *md = dev->msi.data;
struct xarray *xa = &md->__domains[domid].store;
unsigned int hwsize;
int ret;
hwsize = msi_domain_get_hwsize(dev, domid);
if (index == MSI_ANY_INDEX) {
struct xa_limit limit = { .min = 0, .max = hwsize - 1 };
unsigned int index;
/* Let the xarray allocate a free index within the limit */
ret = xa_alloc(xa, &index, desc, limit, GFP_KERNEL);
if (ret)
goto fail;
desc->msi_index = index;
return 0;
} else {
if (index >= hwsize) {
ret = -ERANGE;
goto fail;
}
desc->msi_index = index;
ret = xa_insert(xa, index, desc, GFP_KERNEL);
if (ret)
goto fail;
return 0;
}
fail:
msi_free_desc(desc);
return ret;
}
/**
* msi_domain_insert_msi_desc - Allocate and initialize a MSI descriptor and
* insert it at @init_desc->msi_index
*
* @dev: Pointer to the device for which the descriptor is allocated
* @domid: The id of the interrupt domain to which the desriptor is added
* @init_desc: Pointer to an MSI descriptor to initialize the new descriptor
*
* Return: 0 on success or an appropriate failure code.
*/
int msi_domain_insert_msi_desc(struct device *dev, unsigned int domid,
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, desc, domid, init_desc->msi_index);
}
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;
}
static bool msi_ctrl_valid(struct device *dev, struct msi_ctrl *ctrl)
{
unsigned int hwsize;
if (WARN_ON_ONCE(ctrl->domid >= MSI_MAX_DEVICE_IRQDOMAINS ||
(dev->msi.domain &&
!dev->msi.data->__domains[ctrl->domid].domain)))
return false;
hwsize = msi_domain_get_hwsize(dev, ctrl->domid);
if (WARN_ON_ONCE(ctrl->first > ctrl->last ||
ctrl->first >= hwsize ||
ctrl->last >= hwsize))
return false;
return true;
}
static void msi_domain_free_descs(struct device *dev, struct msi_ctrl *ctrl)
{
struct msi_desc *desc;
struct xarray *xa;
unsigned long idx;
lockdep_assert_held(&dev->msi.data->mutex);
if (!msi_ctrl_valid(dev, ctrl))
return;
xa = &dev->msi.data->__domains[ctrl->domid].store;
xa_for_each_range(xa, idx, desc, ctrl->first, ctrl->last) {
xa_erase(xa, idx);
/* Leak the descriptor when it is still referenced */
if (WARN_ON_ONCE(msi_desc_match(desc, MSI_DESC_ASSOCIATED)))
continue;
msi_free_desc(desc);
}
}
/**
* msi_domain_free_msi_descs_range - Free a range of MSI descriptors of a device in an irqdomain
* @dev: Device for which to free the descriptors
* @domid: Id of the domain to operate on
* @first: Index to start freeing from (inclusive)
* @last: Last index to be freed (inclusive)
*/
void msi_domain_free_msi_descs_range(struct device *dev, unsigned int domid,
unsigned int first, unsigned int last)
{
struct msi_ctrl ctrl = {
.domid = domid,
.first = first,
.last = last,
};
msi_domain_free_descs(dev, &ctrl);
}
/**
* msi_domain_add_simple_msi_descs - Allocate and initialize MSI descriptors
* @dev: Pointer to the device for which the descriptors are allocated
* @ctrl: Allocation control struct
*
* Return: 0 on success or an appropriate failure code.
*/
static int msi_domain_add_simple_msi_descs(struct device *dev, struct msi_ctrl *ctrl)
{
struct msi_desc *desc;
unsigned int idx;
int ret;
lockdep_assert_held(&dev->msi.data->mutex);
if (!msi_ctrl_valid(dev, ctrl))
return -EINVAL;
for (idx = ctrl->first; idx <= ctrl->last; idx++) {
desc = msi_alloc_desc(dev, 1, NULL);
if (!desc)
goto fail_mem;
ret = msi_insert_desc(dev, desc, ctrl->domid, idx);
if (ret)
goto fail;
}
return 0;
fail_mem:
ret = -ENOMEM;
fail:
msi_domain_free_descs(dev, ctrl);
return ret;
}
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;
int i;
for (i = 0; i < MSI_MAX_DEVICE_IRQDOMAINS; i++) {
msi_remove_device_irq_domain(dev, i);
WARN_ON_ONCE(!xa_empty(&md->__domains[i].store));
xa_destroy(&md->__domains[i].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, i;
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;
}
for (i = 0; i < MSI_MAX_DEVICE_IRQDOMAINS; i++)
xa_init_flags(&md->__domains[i].store, XA_FLAGS_ALLOC);
/*
* If @dev::msi::domain is set and is a global MSI domain, copy the
* pointer into the domain array so all code can operate on domain
* ids. The NULL pointer check is required to keep the legacy
* architecture specific PCI/MSI support working.
*/
if (dev->msi.domain && !irq_domain_is_msi_parent(dev->msi.domain))
md->__domains[MSI_DEFAULT_DOMAIN].domain = dev->msi.domain;
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 which was cached by the iterator */
dev->msi.data->__iter_idx = MSI_XA_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, unsigned int domid,
enum msi_desc_filter filter)
{
struct xarray *xa = &md->__domains[domid].store;
struct msi_desc *desc;
xa_for_each_start(xa, md->__iter_idx, desc, md->__iter_idx) {
if (msi_desc_match(desc, filter))
return desc;
}
md->__iter_idx = MSI_XA_MAX_INDEX;
return NULL;
}
/**
* msi_domain_first_desc - Get the first MSI descriptor of an irqdomain associated to a device
* @dev: Device to operate on
* @domid: The id of the interrupt domain which should be walked.
* @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_domain_first_desc(struct device *dev, unsigned int domid,
enum msi_desc_filter filter)
{
struct msi_device_data *md = dev->msi.data;
if (WARN_ON_ONCE(!md || domid >= MSI_MAX_DEVICE_IRQDOMAINS))
return NULL;
lockdep_assert_held(&md->mutex);
md->__iter_idx = 0;
return msi_find_desc(md, domid, filter);
}
EXPORT_SYMBOL_GPL(msi_domain_first_desc);
/**
* msi_next_desc - Get the next MSI descriptor of a device
* @dev: Device to operate on
* @domid: The id of the interrupt domain which should be walked.
* @filter: Descriptor state filter
*
* 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, unsigned int domid,
enum msi_desc_filter filter)
{
struct msi_device_data *md = dev->msi.data;
if (WARN_ON_ONCE(!md || domid >= MSI_MAX_DEVICE_IRQDOMAINS))
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, domid, filter);
}
EXPORT_SYMBOL_GPL(msi_next_desc);
/**
* msi_domain_get_virq - Lookup the Linux interrupt number for a MSI index on a interrupt domain
* @dev: Device to operate on
* @domid: Domain ID of the interrupt domain associated to the device
* @index: MSI interrupt index to look for (0-based)
*
* Return: The Linux interrupt number on success (> 0), 0 if not found
*/
unsigned int msi_domain_get_virq(struct device *dev, unsigned int domid, unsigned int index)
{
struct msi_desc *desc;
unsigned int ret = 0;
bool pcimsi = false;
struct xarray *xa;
if (!dev->msi.data)
return 0;
if (WARN_ON_ONCE(index > MSI_MAX_INDEX || domid >= MSI_MAX_DEVICE_IRQDOMAINS))
return 0;
/* This check is only valid for the PCI default MSI domain */
if (dev_is_pci(dev) && domid == MSI_DEFAULT_DOMAIN)
pcimsi = to_pci_dev(dev)->msi_enabled;
msi_lock_descs(dev);
xa = &dev->msi.data->__domains[domid].store;
desc = xa_load(xa, 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_domain_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 */
static struct irq_domain *msi_get_device_domain(struct device *dev, unsigned int domid)
{
struct irq_domain *domain;
lockdep_assert_held(&dev->msi.data->mutex);
if (WARN_ON_ONCE(domid >= MSI_MAX_DEVICE_IRQDOMAINS))
return NULL;
domain = dev->msi.data->__domains[domid].domain;
if (!domain)
return NULL;
if (WARN_ON_ONCE(irq_domain_is_msi_parent(domain)))
return NULL;
return domain;
}
static unsigned int msi_domain_get_hwsize(struct device *dev, unsigned int domid)
{
struct msi_domain_info *info;
struct irq_domain *domain;
domain = msi_get_device_domain(dev, domid);
if (domain) {
info = domain->host_data;
return info->hwsize;
}
/* No domain, default to MSI_XA_DOMAIN_SIZE */
return MSI_XA_DOMAIN_SIZE;
}
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 struct msi_domain_ops msi_domain_ops_default = {
.get_hwirq = msi_domain_ops_get_hwirq,
.msi_init = msi_domain_ops_init,
.msi_prepare = msi_domain_ops_prepare,
.set_desc = msi_domain_ops_set_desc,
};
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 (!(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_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;
}
static struct irq_domain *__msi_create_irq_domain(struct fwnode_handle *fwnode,
struct msi_domain_info *info,
unsigned int flags,
struct irq_domain *parent)
{
struct irq_domain *domain;
if (info->hwsize > MSI_XA_DOMAIN_SIZE)
return NULL;
/*
* Hardware size 0 is valid for backwards compatibility and for
* domains which are not backed by a hardware table. Grant the
* maximum index space.
*/
if (!info->hwsize)
info->hwsize = MSI_XA_DOMAIN_SIZE;
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, flags | IRQ_DOMAIN_FLAG_MSI, 0,
fwnode, &msi_domain_ops, info);
if (domain)
irq_domain_update_bus_token(domain, info->bus_token);
return domain;
}
/**
* 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)
{
return __msi_create_irq_domain(fwnode, info, 0, parent);
}
/**
* msi_parent_init_dev_msi_info - Delegate initialization of device MSI info down
* in the domain hierarchy
* @dev: The device for which the domain should be created
* @domain: The domain in the hierarchy this op is being called on
* @msi_parent_domain: The IRQ_DOMAIN_FLAG_MSI_PARENT domain for the child to
* be created
* @msi_child_info: The MSI domain info of the IRQ_DOMAIN_FLAG_MSI_DEVICE
* domain to be created
*
* Return: true on success, false otherwise
*
* This is the most complex problem of per device MSI domains and the
* underlying interrupt domain hierarchy:
*
* The device domain to be initialized requests the broadest feature set
* possible and the underlying domain hierarchy puts restrictions on it.
*
* That's trivial for a simple parent->child relationship, but it gets
* interesting with an intermediate domain: root->parent->child. The
* intermediate 'parent' can expand the capabilities which the 'root'
* domain is providing. So that creates a classic hen and egg problem:
* Which entity is doing the restrictions/expansions?
*
* One solution is to let the root domain handle the initialization that's
* why there is the @domain and the @msi_parent_domain pointer.
*/
bool msi_parent_init_dev_msi_info(struct device *dev, struct irq_domain *domain,
struct irq_domain *msi_parent_domain,
struct msi_domain_info *msi_child_info)
{
struct irq_domain *parent = domain->parent;
if (WARN_ON_ONCE(!parent || !parent->msi_parent_ops ||
!parent->msi_parent_ops->init_dev_msi_info))
return false;
return parent->msi_parent_ops->init_dev_msi_info(dev, parent, msi_parent_domain,
msi_child_info);
}
/**
* msi_create_device_irq_domain - Create a device MSI interrupt domain
* @dev: Pointer to the device
* @domid: Domain id
* @template: MSI domain info bundle used as template
* @hwsize: Maximum number of MSI table entries (0 if unknown or unlimited)
* @domain_data: Optional pointer to domain specific data which is set in
* msi_domain_info::data
* @chip_data: Optional pointer to chip specific data which is set in
* msi_domain_info::chip_data
*
* Return: True on success, false otherwise
*
* There is no firmware node required for this interface because the per
* device domains are software constructs which are actually closer to the
* hardware reality than any firmware can describe them.
*
* The domain name and the irq chip name for a MSI device domain are
* composed by: "$(PREFIX)$(CHIPNAME)-$(DEVNAME)"
*
* $PREFIX: Optional prefix provided by the underlying MSI parent domain
* via msi_parent_ops::prefix. If that pointer is NULL the prefix
* is empty.
* $CHIPNAME: The name of the irq_chip in @template
* $DEVNAME: The name of the device
*
* This results in understandable chip names and hardware interrupt numbers
* in e.g. /proc/interrupts
*
* PCI-MSI-0000:00:1c.0 0-edge Parent domain has no prefix
* IR-PCI-MSI-0000:00:1c.4 0-edge Same with interrupt remapping prefix 'IR-'
*
* IR-PCI-MSIX-0000:3d:00.0 0-edge Hardware interrupt numbers reflect
* IR-PCI-MSIX-0000:3d:00.0 1-edge the real MSI-X index on that device
* IR-PCI-MSIX-0000:3d:00.0 2-edge
*
* On IMS domains the hardware interrupt number is either a table entry
* index or a purely software managed index but it is guaranteed to be
* unique.
*
* The domain pointer is stored in @dev::msi::data::__irqdomains[]. All
* subsequent operations on the domain depend on the domain id.
*
* The domain is automatically freed when the device is removed via devres
* in the context of @dev::msi::data freeing, but it can also be
* independently removed via @msi_remove_device_irq_domain().
*/
bool msi_create_device_irq_domain(struct device *dev, unsigned int domid,
const struct msi_domain_template *template,
unsigned int hwsize, void *domain_data,
void *chip_data)
{
struct irq_domain *domain, *parent = dev->msi.domain;
const struct msi_parent_ops *pops;
struct msi_domain_template *bundle;
struct fwnode_handle *fwnode;
if (!irq_domain_is_msi_parent(parent))
return false;
if (domid >= MSI_MAX_DEVICE_IRQDOMAINS)
return false;
bundle = kmemdup(template, sizeof(*bundle), GFP_KERNEL);
if (!bundle)
return false;
bundle->info.hwsize = hwsize;
bundle->info.chip = &bundle->chip;
bundle->info.ops = &bundle->ops;
bundle->info.data = domain_data;
bundle->info.chip_data = chip_data;
pops = parent->msi_parent_ops;
snprintf(bundle->name, sizeof(bundle->name), "%s%s-%s",
pops->prefix ? : "", bundle->chip.name, dev_name(dev));
bundle->chip.name = bundle->name;
fwnode = irq_domain_alloc_named_fwnode(bundle->name);
if (!fwnode)
goto free_bundle;
if (msi_setup_device_data(dev))
goto free_fwnode;
msi_lock_descs(dev);
if (WARN_ON_ONCE(msi_get_device_domain(dev, domid)))
goto fail;
if (!pops->init_dev_msi_info(dev, parent, parent, &bundle->info))
goto fail;
domain = __msi_create_irq_domain(fwnode, &bundle->info, IRQ_DOMAIN_FLAG_MSI_DEVICE, parent);
if (!domain)
goto fail;
domain->dev = dev;
dev->msi.data->__domains[domid].domain = domain;
msi_unlock_descs(dev);
return true;
fail:
msi_unlock_descs(dev);
free_fwnode:
irq_domain_free_fwnode(fwnode);
free_bundle:
kfree(bundle);
return false;
}
/**
* msi_remove_device_irq_domain - Free a device MSI interrupt domain
* @dev: Pointer to the device
* @domid: Domain id
*/
void msi_remove_device_irq_domain(struct device *dev, unsigned int domid)
{
struct fwnode_handle *fwnode = NULL;
struct msi_domain_info *info;
struct irq_domain *domain;
msi_lock_descs(dev);
domain = msi_get_device_domain(dev, domid);
if (!domain || !irq_domain_is_msi_device(domain))
goto unlock;
dev->msi.data->__domains[domid].domain = NULL;
info = domain->host_data;
if (irq_domain_is_msi_device(domain))
fwnode = domain->fwnode;
irq_domain_remove(domain);
irq_domain_free_fwnode(fwnode);
kfree(container_of(info, struct msi_domain_template, info));
unlock:
msi_unlock_descs(dev);
}
/**
* msi_match_device_irq_domain - Match a device irq domain against a bus token
* @dev: Pointer to the device
* @domid: Domain id
* @bus_token: Bus token to match against the domain bus token
*
* Return: True if device domain exists and bus tokens match.
*/
bool msi_match_device_irq_domain(struct device *dev, unsigned int domid,
enum irq_domain_bus_token bus_token)
{
struct msi_domain_info *info;
struct irq_domain *domain;
bool ret = false;
msi_lock_descs(dev);
domain = msi_get_device_domain(dev, domid);
if (domain && irq_domain_is_msi_device(domain)) {
info = domain->host_data;
ret = info->bus_token == bus_token;
}
msi_unlock_descs(dev);
return ret;
}
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;
return ops->msi_prepare(domain, dev, nvec, arg);
}
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_ctrl ctrl = {
.domid = MSI_DEFAULT_DOMAIN,
.first = virq_base,
.last = virq_base + nvec - 1,
};
struct msi_desc *desc;
struct xarray *xa;
int ret, virq;
msi_lock_descs(dev);
if (!msi_ctrl_valid(dev, &ctrl)) {
ret = -EINVAL;
goto unlock;
}
ret = msi_domain_add_simple_msi_descs(dev, &ctrl);
if (ret)
goto unlock;
xa = &dev->msi.data->__domains[ctrl.domid].store;
for (virq = virq_base; virq < virq_base + nvec; virq++) {
desc = xa_load(xa, 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--) {
msi_domain_depopulate_descs(dev, virq, 1);
irq_domain_free_irqs_common(domain, virq, 1);
}
msi_domain_free_descs(dev, &ctrl);
unlock:
msi_unlock_descs(dev);
return ret;
}
void msi_domain_depopulate_descs(struct device *dev, int virq_base, int nvec)
{
struct msi_ctrl ctrl = {
.domid = MSI_DEFAULT_DOMAIN,
.first = virq_base,
.last = virq_base + nvec - 1,
};
struct msi_desc *desc;
struct xarray *xa;
unsigned long idx;
if (!msi_ctrl_valid(dev, &ctrl))
return;
xa = &dev->msi.data->__domains[ctrl.domid].store;
xa_for_each_range(xa, idx, desc, ctrl.first, ctrl.last)
desc->irq = 0;
}
/*
* 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_PCI_DEVICE_MSI:
case DOMAIN_BUS_PCI_DEVICE_MSIX:
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_PCI_DEVICE_MSI:
case DOMAIN_BUS_PCI_DEVICE_MSIX:
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 the interrupt is managed but no CPU is available to
* service it, shut it down until better times. Note that
* we only do this on the !RESERVE path as x86 (the only
* architecture using this flag) deals with this in a
* different way by using a catch-all vector.
*/
if ((vflags & VIRQ_ACTIVATE) &&
irqd_affinity_is_managed(irqd) &&
!cpumask_intersects(irq_data_get_affinity_mask(irqd),
cpu_online_mask)) {
irqd_set_managed_shutdown(irqd);
return 0;
}
}
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;
}
static int __msi_domain_alloc_irqs(struct device *dev, struct irq_domain *domain,
struct msi_ctrl *ctrl)
{
struct xarray *xa = &dev->msi.data->__domains[ctrl->domid].store;
struct msi_domain_info *info = domain->host_data;
struct msi_domain_ops *ops = info->ops;
unsigned int vflags = 0, allocated = 0;
msi_alloc_info_t arg = { };
struct msi_desc *desc;
unsigned long idx;
int i, ret, virq;
ret = msi_domain_prepare_irqs(domain, dev, ctrl->nirqs, &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 (info->flags & MSI_FLAG_NOMASK_QUIRK)
vflags |= VIRQ_NOMASK_QUIRK;
}
xa_for_each_range(xa, idx, desc, ctrl->first, ctrl->last) {
if (!msi_desc_match(desc, MSI_DESC_NOTASSOCIATED))
continue;
/* This should return -ECONFUSED... */
if (WARN_ON_ONCE(allocated >= ctrl->nirqs))
return -EINVAL;
if (ops->prepare_desc)
ops->prepare_desc(domain, &arg, desc);
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_alloc_simple_msi_descs(struct device *dev,
struct msi_domain_info *info,
struct msi_ctrl *ctrl)
{
if (!(info->flags & MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS))
return 0;
return msi_domain_add_simple_msi_descs(dev, ctrl);
}
static int __msi_domain_alloc_locked(struct device *dev, struct msi_ctrl *ctrl)
{
struct msi_domain_info *info;
struct msi_domain_ops *ops;
struct irq_domain *domain;
int ret;
if (!msi_ctrl_valid(dev, ctrl))
return -EINVAL;
domain = msi_get_device_domain(dev, ctrl->domid);
if (!domain)
return -ENODEV;
info = domain->host_data;
ret = msi_domain_alloc_simple_msi_descs(dev, info, ctrl);
if (ret)
return ret;
ops = info->ops;
if (ops->domain_alloc_irqs)
return ops->domain_alloc_irqs(domain, dev, ctrl->nirqs);
return __msi_domain_alloc_irqs(dev, domain, ctrl);
}
static int msi_domain_alloc_locked(struct device *dev, struct msi_ctrl *ctrl)
{
int ret = __msi_domain_alloc_locked(dev, ctrl);
if (ret)
msi_domain_free_locked(dev, ctrl);
return ret;
}
/**
* msi_domain_alloc_irqs_range_locked - Allocate interrupts from a MSI interrupt domain
* @dev: Pointer to device struct of the device for which the interrupts
* are allocated
* @domid: Id of the interrupt domain to operate on
* @first: First index to allocate (inclusive)
* @last: Last index to allocate (inclusive)
*
* Must be invoked from within a msi_lock_descs() / msi_unlock_descs()
* pair. Use this for MSI irqdomains which implement their own descriptor
* allocation/free.
*
* Return: %0 on success or an error code.
*/
int msi_domain_alloc_irqs_range_locked(struct device *dev, unsigned int domid,
unsigned int first, unsigned int last)
{
struct msi_ctrl ctrl = {
.domid = domid,
.first = first,
.last = last,
.nirqs = last + 1 - first,
};
return msi_domain_alloc_locked(dev, &ctrl);
}
/**
* msi_domain_alloc_irqs_range - Allocate interrupts from a MSI interrupt domain
* @dev: Pointer to device struct of the device for which the interrupts
* are allocated
* @domid: Id of the interrupt domain to operate on
* @first: First index to allocate (inclusive)
* @last: Last index to allocate (inclusive)
*
* Return: %0 on success or an error code.
*/
int msi_domain_alloc_irqs_range(struct device *dev, unsigned int domid,
unsigned int first, unsigned int last)
{
int ret;
msi_lock_descs(dev);
ret = msi_domain_alloc_irqs_range_locked(dev, domid, first, last);
msi_unlock_descs(dev);
return ret;
}
/**
* msi_domain_alloc_irqs_all_locked - Allocate all interrupts from a MSI interrupt domain
*
* @dev: Pointer to device struct of the device for which the interrupts
* are allocated
* @domid: Id of the interrupt domain to operate on
* @nirqs: The number of interrupts to allocate
*
* This function scans all MSI descriptors of the MSI domain and allocates interrupts
* for all unassigned ones. That function is to be used for MSI domain usage where
* the descriptor allocation is handled at the call site, e.g. PCI/MSI[X].
*
* Return: %0 on success or an error code.
*/
int msi_domain_alloc_irqs_all_locked(struct device *dev, unsigned int domid, int nirqs)
{
struct msi_ctrl ctrl = {
.domid = domid,
.first = 0,
.last = msi_domain_get_hwsize(dev, domid) - 1,
.nirqs = nirqs,
};
return msi_domain_alloc_locked(dev, &ctrl);
}
/**
* msi_domain_alloc_irq_at - Allocate an interrupt from a MSI interrupt domain at
* a given index - or at the next free index
*
* @dev: Pointer to device struct of the device for which the interrupts
* are allocated
* @domid: Id of the interrupt domain to operate on
* @index: Index for allocation. If @index == %MSI_ANY_INDEX the allocation
* uses the next free index.
* @affdesc: Optional pointer to an interrupt affinity descriptor structure
* @icookie: Optional pointer to a domain specific per instance cookie. If
* non-NULL the content of the cookie is stored in msi_desc::data.
* Must be NULL for MSI-X allocations
*
* This requires a MSI interrupt domain which lets the core code manage the
* MSI descriptors.
*
* Return: struct msi_map
*
* On success msi_map::index contains the allocated index number and
* msi_map::virq the corresponding Linux interrupt number
*
* On failure msi_map::index contains the error code and msi_map::virq
* is %0.
*/
struct msi_map msi_domain_alloc_irq_at(struct device *dev, unsigned int domid, unsigned int index,
const struct irq_affinity_desc *affdesc,
union msi_instance_cookie *icookie)
{
struct msi_ctrl ctrl = { .domid = domid, .nirqs = 1, };
struct irq_domain *domain;
struct msi_map map = { };
struct msi_desc *desc;
int ret;
msi_lock_descs(dev);
domain = msi_get_device_domain(dev, domid);
if (!domain) {
map.index = -ENODEV;
goto unlock;
}
desc = msi_alloc_desc(dev, 1, affdesc);
if (!desc) {
map.index = -ENOMEM;
goto unlock;
}
if (icookie)
desc->data.icookie = *icookie;
ret = msi_insert_desc(dev, desc, domid, index);
if (ret) {
map.index = ret;
goto unlock;
}
ctrl.first = ctrl.last = desc->msi_index;
ret = __msi_domain_alloc_irqs(dev, domain, &ctrl);
if (ret) {
map.index = ret;
msi_domain_free_locked(dev, &ctrl);
} else {
map.index = desc->msi_index;
map.virq = desc->irq;
}
unlock:
msi_unlock_descs(dev);
return map;
}
static void __msi_domain_free_irqs(struct device *dev, struct irq_domain *domain,
struct msi_ctrl *ctrl)
{
struct xarray *xa = &dev->msi.data->__domains[ctrl->domid].store;
struct msi_domain_info *info = domain->host_data;
struct irq_data *irqd;
struct msi_desc *desc;
unsigned long idx;
int i;
xa_for_each_range(xa, idx, desc, ctrl->first, ctrl->last) {
/* Only handle MSI entries which have an interrupt associated */
if (!msi_desc_match(desc, MSI_DESC_ASSOCIATED))
continue;
/* 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_locked(struct device *dev, struct msi_ctrl *ctrl)
{
struct msi_domain_info *info;
struct msi_domain_ops *ops;
struct irq_domain *domain;
if (!msi_ctrl_valid(dev, ctrl))
return;
domain = msi_get_device_domain(dev, ctrl->domid);
if (!domain)
return;
info = domain->host_data;
ops = info->ops;
if (ops->domain_free_irqs)
ops->domain_free_irqs(domain, dev);
else
__msi_domain_free_irqs(dev, domain, ctrl);
if (ops->msi_post_free)
ops->msi_post_free(domain, dev);
if (info->flags & MSI_FLAG_FREE_MSI_DESCS)
msi_domain_free_descs(dev, ctrl);
}
/**
* msi_domain_free_irqs_range_locked - Free a range of interrupts from a MSI interrupt domain
* associated to @dev with msi_lock held
* @dev: Pointer to device struct of the device for which the interrupts
* are freed
* @domid: Id of the interrupt domain to operate on
* @first: First index to free (inclusive)
* @last: Last index to free (inclusive)
*/
void msi_domain_free_irqs_range_locked(struct device *dev, unsigned int domid,
unsigned int first, unsigned int last)
{
struct msi_ctrl ctrl = {
.domid = domid,
.first = first,
.last = last,
};
msi_domain_free_locked(dev, &ctrl);
}
/**
* msi_domain_free_irqs_range - Free a range of interrupts from a MSI interrupt domain
* associated to @dev
* @dev: Pointer to device struct of the device for which the interrupts
* are freed
* @domid: Id of the interrupt domain to operate on
* @first: First index to free (inclusive)
* @last: Last index to free (inclusive)
*/
void msi_domain_free_irqs_range(struct device *dev, unsigned int domid,
unsigned int first, unsigned int last)
{
msi_lock_descs(dev);
msi_domain_free_irqs_range_locked(dev, domid, first, last);
msi_unlock_descs(dev);
}
/**
* msi_domain_free_irqs_all_locked - Free all interrupts from a MSI interrupt domain
* associated to a device
* @dev: Pointer to device struct of the device for which the interrupts
* are freed
* @domid: The id of the domain to operate on
*
* 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_all_locked(struct device *dev, unsigned int domid)
{
msi_domain_free_irqs_range_locked(dev, domid, 0,
msi_domain_get_hwsize(dev, domid) - 1);
}
/**
* msi_domain_free_irqs_all - Free all interrupts from a MSI interrupt domain
* associated to a device
* @dev: Pointer to device struct of the device for which the interrupts
* are freed
* @domid: The id of the domain to operate on
*/
void msi_domain_free_irqs_all(struct device *dev, unsigned int domid)
{
msi_lock_descs(dev);
msi_domain_free_irqs_all_locked(dev, domid);
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;
}
/**
* msi_device_has_isolated_msi - True if the device has isolated MSI
* @dev: The device to check
*
* Isolated MSI means that HW modeled by an irq_domain on the path from the
* initiating device to the CPU will validate that the MSI message specifies an
* interrupt number that the device is authorized to trigger. This must block
* devices from triggering interrupts they are not authorized to trigger.
* Currently authorization means the MSI vector is one assigned to the device.
*
* This is interesting for securing VFIO use cases where a rouge MSI (eg created
* by abusing a normal PCI MemWr DMA) must not allow the VFIO userspace to
* impact outside its security domain, eg userspace triggering interrupts on
* kernel drivers, a VM triggering interrupts on the hypervisor, or a VM
* triggering interrupts on another VM.
*/
bool msi_device_has_isolated_msi(struct device *dev)
{
struct irq_domain *domain = dev_get_msi_domain(dev);
for (; domain; domain = domain->parent)
if (domain->flags & IRQ_DOMAIN_FLAG_ISOLATED_MSI)
return true;
return arch_is_isolated_msi();
}
EXPORT_SYMBOL_GPL(msi_device_has_isolated_msi);