diff options
| -rw-r--r-- | include/linux/msi.h | 2 | ||||
| -rw-r--r-- | kernel/irq/msi.c | 59 |
2 files changed, 61 insertions, 0 deletions
diff --git a/include/linux/msi.h b/include/linux/msi.h index 703221f7e9ea..bbb8c1e2c18b 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -247,6 +247,8 @@ static inline void pci_write_msi_msg(unsigned int irq, struct msi_msg *msg) } #endif /* CONFIG_PCI_MSI */ +int msi_add_msi_desc(struct device *dev, struct msi_desc *init_desc); + struct msi_desc *alloc_msi_entry(struct device *dev, int nvec, const struct irq_affinity_desc *affinity); void free_msi_entry(struct msi_desc *entry); diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c index bc67b2cafc9d..6ffe75eeba59 100644 --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -60,6 +60,65 @@ void free_msi_entry(struct msi_desc *entry) kfree(entry); } +/** + * 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 = alloc_msi_entry(dev, init_desc->nvec_used, init_desc->affinity); + if (!desc) + return -ENOMEM; + + /* Copy the MSI index and type specific data to the new descriptor. */ + desc->msi_index = init_desc->msi_index; + desc->pci = init_desc->pci; + + list_add_tail(&desc->list, &dev->msi.data->list); + return 0; +} + +/** + * 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) +{ + struct msi_desc *desc, *tmp; + LIST_HEAD(list); + unsigned int i; + + lockdep_assert_held(&dev->msi.data->mutex); + + for (i = 0; i < ndesc; i++) { + desc = alloc_msi_entry(dev, 1, NULL); + if (!desc) + goto fail; + desc->msi_index = index + i; + list_add_tail(&desc->list, &list); + } + list_splice_tail(&list, &dev->msi.data->list); + return 0; + +fail: + list_for_each_entry_safe(desc, tmp, &list, list) { + list_del(&desc->list); + free_msi_entry(desc); + } + return -ENOMEM; +} + void __get_cached_msi_msg(struct msi_desc *entry, struct msi_msg *msg) { *msg = entry->msg; |