genirq/irqdomain: Allow irq_domain_activate_irq() to fail

Allow irq_domain_activate_irq() to fail. This is required to support a
reservation and late vector assignment scheme.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Yu Chen <yu.c.chen@intel.com>
Acked-by: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rui Zhang <rui.zhang@intel.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Len Brown <lenb@kernel.org>
Link: https://lkml.kernel.org/r/20170913213152.933882227@linutronix.de

5 files changed, 52 insertions, 21 deletions

diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
index 9bc07f59b090..8fb877121984 100644
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -441,7 +441,7 @@ extern int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base,
                                    unsigned int nr_irqs, int node, void *arg,
                                    bool realloc, const struct cpumask *affinity);
 extern void irq_domain_free_irqs(unsigned int virq, unsigned int nr_irqs);
-extern void irq_domain_activate_irq(struct irq_data *irq_data);
+extern int irq_domain_activate_irq(struct irq_data *irq_data);
 extern void irq_domain_deactivate_irq(struct irq_data *irq_data);
 
 static inline int irq_domain_alloc_irqs(struct irq_domain *domain,
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 37dd34d922f4..cd5b3eb38082 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -219,7 +219,12 @@ __irq_startup_managed(struct irq_desc *desc, struct cpumask *aff, bool force)
                  */
                 return IRQ_STARTUP_ABORT;
         }
-        irq_domain_activate_irq(d);
+        /*
+         * Managed interrupts have reserved resources, so this should not
+         * happen.
+         */
+        if (WARN_ON(irq_domain_activate_irq(d)))
+                return IRQ_STARTUP_ABORT;
         return IRQ_STARTUP_MANAGED;
 }
 #else
@@ -285,7 +290,7 @@ int irq_activate(struct irq_desc *desc)
         struct irq_data *d = irq_desc_get_irq_data(desc);
 
         if (!irqd_affinity_is_managed(d))
-                irq_domain_activate_irq(d);
+                return irq_domain_activate_irq(d);
         return 0;
 }
 
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index 8bd131e4c944..e84d0e3899f6 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -439,9 +439,10 @@ static inline bool irq_fixup_move_pending(struct irq_desc *desc, bool fclear)
 #endif /* !CONFIG_GENERIC_PENDING_IRQ */
 
 #if !defined(CONFIG_IRQ_DOMAIN) || !defined(CONFIG_IRQ_DOMAIN_HIERARCHY)
-static inline void irq_domain_activate_irq(struct irq_data *data)
+static inline int irq_domain_activate_irq(struct irq_data *data)
 {
         irqd_set_activated(data);
+        return 0;
 }
 static inline void irq_domain_deactivate_irq(struct irq_data *data)
 {
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 1423f8a6c75d..47e8ddd9e8cf 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -1682,28 +1682,35 @@ void irq_domain_free_irqs_parent(struct irq_domain *domain,
 }
 EXPORT_SYMBOL_GPL(irq_domain_free_irqs_parent);
 
-static void __irq_domain_activate_irq(struct irq_data *irq_data)
+static void __irq_domain_deactivate_irq(struct irq_data *irq_data)
 {
         if (irq_data && irq_data->domain) {
                 struct irq_domain *domain = irq_data->domain;
 
+                if (domain->ops->deactivate)
+                        domain->ops->deactivate(domain, irq_data);
                 if (irq_data->parent_data)
-                        __irq_domain_activate_irq(irq_data->parent_data);
-                if (domain->ops->activate)
-                        domain->ops->activate(domain, irq_data, false);
+                        __irq_domain_deactivate_irq(irq_data->parent_data);
         }
 }
 
-static void __irq_domain_deactivate_irq(struct irq_data *irq_data)
+static int __irq_domain_activate_irq(struct irq_data *irqd)
 {
-        if (irq_data && irq_data->domain) {
-                struct irq_domain *domain = irq_data->domain;
+        int ret = 0;
 
-                if (domain->ops->deactivate)
-                        domain->ops->deactivate(domain, irq_data);
-                if (irq_data->parent_data)
-                        __irq_domain_deactivate_irq(irq_data->parent_data);
+        if (irqd && irqd->domain) {
+                struct irq_domain *domain = irqd->domain;
+
+                if (irqd->parent_data)
+                        ret = __irq_domain_activate_irq(irqd->parent_data);
+                if (!ret && domain->ops->activate) {
+                        ret = domain->ops->activate(domain, irqd, false);
+                        /* Rollback in case of error */
+                        if (ret && irqd->parent_data)
+                                __irq_domain_deactivate_irq(irqd->parent_data);
+                }
         }
+        return ret;
 }
 
 /**
@@ -1714,12 +1721,15 @@ static void __irq_domain_deactivate_irq(struct irq_data *irq_data)
  * This is the second step to call domain_ops->activate to program interrupt
  * controllers, so the interrupt could actually get delivered.
  */
-void irq_domain_activate_irq(struct irq_data *irq_data)
+int irq_domain_activate_irq(struct irq_data *irq_data)
 {
-        if (!irqd_is_activated(irq_data)) {
-                __irq_domain_activate_irq(irq_data);
+        int ret = 0;
+
+        if (!irqd_is_activated(irq_data))
+                ret = __irq_domain_activate_irq(irq_data);
+        if (!ret)
                 irqd_set_activated(irq_data);
-        }
+        return ret;
 }
 
 /**
diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c
index 6155fff9f647..5ece369950ec 100644
--- a/kernel/irq/msi.c
+++ b/kernel/irq/msi.c
@@ -401,11 +401,26 @@ int msi_domain_alloc_irqs(struct irq_domain *domain, struct device *dev,
                         struct irq_data *irq_data;
 
                         irq_data = irq_domain_get_irq_data(domain, desc->irq);
-                        irq_domain_activate_irq(irq_data);
+                        ret = irq_domain_activate_irq(irq_data);
+                        if (ret)
+                                goto cleanup;
                 }
         }
-
         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;
 }
 
 /**