From 28026cf2dd84d961a62123b1fa941dc3c2c4a132 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 13 May 2025 17:31:40 +0100 Subject: [PATCH] genirq/msi: Add .msi_teardown() callback as the reverse of .msi_prepare() While the MSI ops do have a .msi_prepare() callback that is responsible for setting up the relevant (usually per-device) allocation, there is no callback reversing this setup. For this purpose, add .msi_teardown() callback. In order to avoid breaking the ITS driver that suffers from related issues, do not call the callback just yet. Signed-off-by: Marc Zyngier Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20250513163144.2215824-2-maz@kernel.org --- include/linux/msi.h | 10 ++++++++-- kernel/irq/msi.c | 8 ++++++++ 2 files changed, 16 insertions(+), 2 deletions(-) diff --git a/include/linux/msi.h b/include/linux/msi.h index 8c0ec9fc05a3..63c23003ec9b 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -423,6 +423,7 @@ struct msi_domain_info; * @msi_init: Domain specific init function for MSI interrupts * @msi_free: Domain specific function to free a MSI interrupts * @msi_prepare: Prepare the allocation of the interrupts in the domain + * @msi_teardown: Reverse the effects of @msi_prepare * @prepare_desc: Optional function to prepare the allocated MSI descriptor * in the domain * @set_desc: Set the msi descriptor for an interrupt @@ -438,8 +439,9 @@ struct msi_domain_info; * @get_hwirq, @msi_init and @msi_free are callbacks used by the underlying * irqdomain. * - * @msi_check, @msi_prepare, @prepare_desc and @set_desc are callbacks used by the - * msi_domain_alloc/free_irqs*() variants. + * @msi_check, @msi_prepare, @msi_teardown, @prepare_desc and + * @set_desc are callbacks used by the msi_domain_alloc/free_irqs*() + * variants. * * @domain_alloc_irqs, @domain_free_irqs can be used to override the * default allocation/free functions (__msi_domain_alloc/free_irqs). This @@ -461,6 +463,8 @@ struct msi_domain_ops { int (*msi_prepare)(struct irq_domain *domain, struct device *dev, int nvec, msi_alloc_info_t *arg); + void (*msi_teardown)(struct irq_domain *domain, + msi_alloc_info_t *arg); void (*prepare_desc)(struct irq_domain *domain, msi_alloc_info_t *arg, struct msi_desc *desc); void (*set_desc)(msi_alloc_info_t *arg, @@ -489,6 +493,7 @@ struct msi_domain_ops { * @handler: Optional: associated interrupt flow handler * @handler_data: Optional: associated interrupt flow handler data * @handler_name: Optional: associated interrupt flow handler name + * @alloc_data: Optional: associated interrupt allocation data * @data: Optional: domain specific data */ struct msi_domain_info { @@ -501,6 +506,7 @@ struct msi_domain_info { irq_flow_handler_t handler; void *handler_data; const char *handler_name; + msi_alloc_info_t *alloc_data; void *data; }; diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c index a8f7701c2929..7f0dfe0e5ccb 100644 --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -795,6 +795,11 @@ static int msi_domain_ops_prepare(struct irq_domain *domain, struct device *dev, return 0; } +static void msi_domain_ops_teardown(struct irq_domain *domain, + msi_alloc_info_t *arg) +{ +} + static void msi_domain_ops_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc) { @@ -820,6 +825,7 @@ 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, + .msi_teardown = msi_domain_ops_teardown, .set_desc = msi_domain_ops_set_desc, }; @@ -841,6 +847,8 @@ static void msi_domain_update_dom_ops(struct msi_domain_info *info) 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->msi_teardown == NULL) + ops->msi_teardown = msi_domain_ops_default.msi_teardown; if (ops->set_desc == NULL) ops->set_desc = msi_domain_ops_default.set_desc; } -- 2.25.1