cregit-Linux how code gets into the kernel

Release 4.15 kernel/irq/msi.c

Directory: kernel/irq
/*
 * linux/kernel/irq/msi.c
 *
 * 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 Signalled Interrupt 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 "internals.h"

/**
 * alloc_msi_entry - Allocate an initialize msi_entry
 * @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 a an affinity array[@nvec] is allocated
 * and the affinity masks from @affinity are copied.
 */

struct msi_desc * alloc_msi_entry(struct device *dev, int nvec, const struct cpumask *affinity) { struct msi_desc *desc; desc = kzalloc(sizeof(*desc), GFP_KERNEL); if (!desc) return NULL; INIT_LIST_HEAD(&desc->list); 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; }

Contributors

PersonTokensPropCommitsCommitProp
Thomas Gleixner6355.26%150.00%
Jiang Liu5144.74%150.00%
Total114100.00%2100.00%


void free_msi_entry(struct msi_desc *entry) { kfree(entry->affinity); kfree(entry); }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu1568.18%150.00%
Thomas Gleixner731.82%150.00%
Total22100.00%2100.00%


void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg) { *msg = entry->msg; }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu22100.00%1100.00%
Total22100.00%1100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu31100.00%1100.00%
Total31100.00%1100.00%

EXPORT_SYMBOL_GPL(get_cached_msi_msg); #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); }

Contributors

PersonTokensPropCommitsCommitProp
Thomas Gleixner28100.00%1100.00%
Total28100.00%1100.00%

/** * 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. */
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; 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)); irq_chip_write_msi_msg(irq_data, &msg); } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu84100.00%1100.00%
Total84100.00%1100.00%


static int msi_domain_activate(struct irq_domain *domain, struct irq_data *irq_data, bool early) { struct msi_msg msg; BUG_ON(irq_chip_compose_msi_msg(irq_data, &msg)); irq_chip_write_msi_msg(irq_data, &msg); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu3884.44%150.00%
Thomas Gleixner715.56%150.00%
Total45100.00%2100.00%


static void msi_domain_deactivate(struct irq_domain *domain, struct irq_data *irq_data) { struct msi_msg msg; memset(&msg, 0, sizeof(msg)); irq_chip_write_msi_msg(irq_data, &msg); }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu41100.00%1100.00%
Total41100.00%1100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu195100.00%2100.00%
Total195100.00%2100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu78100.00%1100.00%
Total78100.00%1100.00%

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, }; #ifdef GENERIC_MSI_DOMAIN_OPS
static irq_hw_number_t msi_domain_ops_get_hwirq(struct msi_domain_info *info, msi_alloc_info_t *arg) { return arg->hwirq; }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu20100.00%1100.00%
Total20100.00%1100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu39100.00%1100.00%
Total39100.00%1100.00%


static void msi_domain_ops_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc) { arg->desc = desc; }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu21100.00%1100.00%
Total21100.00%1100.00%

#else #define msi_domain_ops_get_hwirq NULL #define msi_domain_ops_prepare NULL #define msi_domain_ops_set_desc NULL #endif /* !GENERIC_MSI_DOMAIN_OPS */
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; }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu89100.00%2100.00%
Total89100.00%2100.00%


static int msi_domain_ops_check(struct irq_domain *domain, struct msi_domain_info *info, struct device *dev) { return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu24100.00%2100.00%
Total24100.00%2100.00%

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, };
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->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; }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu116100.00%2100.00%
Total116100.00%2100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu4693.88%266.67%
Marc Zyngier36.12%133.33%
Total49100.00%3100.00%

/** * msi_create_irq_domain - Create a MSI interrupt domain * @fwnode: Optional fwnode of the interrupt controller * @info: MSI domain info * @parent: Parent irq domain */
struct irq_domain *msi_create_irq_domain(struct fwnode_handle *fwnode, struct msi_domain_info *info, struct irq_domain *parent) { struct irq_domain *domain; if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS) 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; }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu5960.82%233.33%
Marc Zyngier3435.05%233.33%
Thomas Gleixner33.09%116.67%
Eric Auger11.03%116.67%
Total97100.00%6100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu6885.00%150.00%
Marc Zyngier1215.00%150.00%
Total80100.00%2100.00%


int msi_domain_populate_irqs(struct irq_domain *domain, struct device *dev, int virq, 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 = 0; for_each_msi_entry(desc, dev) { /* Don't even try the multi-MSI brain damage. */ if (WARN_ON(!desc->irq || desc->nvec_used != 1)) { ret = -EINVAL; break; } if (!(desc->irq >= virq && desc->irq < (virq + nvec))) continue; ops->set_desc(arg, desc); /* Assumes the domain mutex is held! */ ret = irq_domain_alloc_irqs_hierarchy(domain, desc->irq, 1, arg); if (ret) break; irq_set_msi_desc_off(desc->irq, 0, desc); } if (ret) { /* Mop up the damage */ for_each_msi_entry(desc, dev) { if (!(desc->irq >= virq && desc->irq < (virq + nvec))) continue; irq_domain_free_irqs_common(domain, desc->irq, 1); } } return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Marc Zyngier19497.00%266.67%
John Keeping63.00%133.33%
Total200100.00%3100.00%

/* * 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; if (domain->bus_token != DOMAIN_BUS_PCI_MSI) 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 maskbit is set. */ desc = first_msi_entry(dev); return desc->msi_attrib.is_msix || desc->msi_attrib.maskbit; }

Contributors

PersonTokensPropCommitsCommitProp
Thomas Gleixner84100.00%2100.00%
Total84100.00%2100.00%

/** * 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 * * Returns 0 on success or an error code. */
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; struct irq_data *irq_data; struct msi_desc *desc; msi_alloc_info_t arg; int i, ret, virq; bool can_reserve; ret = msi_domain_prepare_irqs(domain, dev, nvec, &arg); if (ret) return ret; for_each_msi_entry(desc, dev) { 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) { ret = -ENOSPC; if (ops->handle_error) ret = ops->handle_error(domain, desc, ret); if (ops->msi_finish) ops->msi_finish(&arg, ret); return ret; } for (i = 0; i < desc->nvec_used; i++) { irq_set_msi_desc_off(virq, i, desc); irq_debugfs_copy_devname(virq + i, dev); } } if (ops->msi_finish) ops->msi_finish(&arg, 0); can_reserve = msi_check_reservation_mode(domain, info, dev); for_each_msi_entry(desc, dev) { virq = desc->irq; if (desc->nvec_used == 1) dev_dbg(dev, "irq %d for MSI\n", virq); else dev_dbg(dev, "irq [%d-%d] for MSI\n", virq, virq + desc->nvec_used - 1); /* * 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)) continue; irq_data = irq_domain_get_irq_data(domain, desc->irq); if (!can_reserve) irqd_clr_can_reserve(irq_data); ret = irq_domain_activate_irq(irq_data, can_reserve); if (ret) goto cleanup; } /* * If these interrupts use reservation mode, clear the activated bit * so request_irq() will assign the final vector. */ if (can_reserve) { for_each_msi_entry(desc, dev) { irq_data = irq_domain_get_irq_data(domain, desc->irq); irqd_clr_activated(irq_data); } } return 0; cleanup: for_each_msi_entry(desc, dev) { struct irq_data *irqd; if (desc->irq == virq) break; irqd = irq_domain_get_irq_data(domain, desc->irq); if (irqd_is_activated(irqd)) irq_domain_deactivate_irq(irqd); } msi_domain_free_irqs(domain, dev); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu18944.06%214.29%
Thomas Gleixner15636.36%1071.43%
Marc Zyngier8419.58%214.29%
Total429100.00%14100.00%

/** * msi_domain_free_irqs - Free interrupts from a MSI interrupt @domain associated tp @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) { 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->irq) { irq_domain_free_irqs(desc->irq, desc->nvec_used); desc->irq = 0; } } }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu4583.33%150.00%
Marc Zyngier916.67%150.00%
Total54100.00%2100.00%

/** * msi_get_domain_info - Get the MSI interrupt domain info for @domain * @domain: The interrupt domain to retrieve data from * * Returns 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; }

Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu22100.00%1100.00%
Total22100.00%1100.00%

#endif /* CONFIG_GENERIC_MSI_IRQ_DOMAIN */

Overall Contributors

PersonTokensPropCommitsCommitProp
Jiang Liu140466.73%618.75%
Thomas Gleixner35316.78%1443.75%
Marc Zyngier33916.11%928.12%
John Keeping60.29%13.12%
Eric Auger10.05%13.12%
Krzysztof Kozlowski10.05%13.12%
Total2104100.00%32100.00%
Directory: kernel/irq
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.