x86, irq: Convert irq_2_pin list to generic list

Use generic list to replace private list implementation so we can use
the existing helper functions.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Grant Likely <grant.likely@linaro.org>
Link: http://lkml.kernel.org/r/1414397531-28254-5-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: Joerg Roedel <joro@8bytes.org>

2 files changed, 12 insertions, 18 deletions

diff --git a/arch/x86/include/asm/hw_irq.h b/arch/x86/include/asm/hw_irq.h
index b12c45c5d8ec..66e59e646deb 100644
--- a/arch/x86/include/asm/hw_irq.h
+++ b/arch/x86/include/asm/hw_irq.h
@@ -138,7 +138,7 @@ struct irq_2_irte {
  * Most irqs are mapped 1:1 with pins.
  */
 struct irq_cfg {
-        struct irq_pin_list     *irq_2_pin;
+        struct list_head        irq_2_pin;
         cpumask_var_t           domain;
         cpumask_var_t           old_domain;
         u8                      vector;
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 447186a0eeee..11978401d0cb 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -74,7 +74,7 @@
                 for_each_pin((idx), (pin))
 
 #define for_each_irq_pin(entry, head) \
-        for (entry = head; entry; entry = entry->next)
+        list_for_each_entry(entry, &head, list)
 
 /*
  *      Is the SiS APIC rmw bug present ?
@@ -229,8 +229,8 @@ void mp_save_irq(struct mpc_intsrc *m)
 }
 
 struct irq_pin_list {
+        struct list_head list;
         int apic, pin;
-        struct irq_pin_list *next;
 };
 
 static struct irq_pin_list *alloc_irq_pin_list(int node)
@@ -297,6 +297,7 @@ static struct irq_cfg *alloc_irq_cfg(unsigned int irq, int node)
                 goto out_cfg;
         if (!zalloc_cpumask_var_node(&cfg->old_domain, GFP_KERNEL, node))
                 goto out_domain;
+        INIT_LIST_HEAD(&cfg->irq_2_pin);
         return cfg;
 out_domain:
         free_cpumask_var(cfg->domain);
@@ -460,15 +461,12 @@ static void ioapic_mask_entry(int apic, int pin)
  */
 static int __add_pin_to_irq_node(struct irq_cfg *cfg, int node, int apic, int pin)
 {
-        struct irq_pin_list **last, *entry;
+        struct irq_pin_list *entry;
 
         /* don't allow duplicates */
-        last = &cfg->irq_2_pin;
-        for_each_irq_pin(entry, cfg->irq_2_pin) {
+        for_each_irq_pin(entry, cfg->irq_2_pin)
                 if (entry->apic == apic && entry->pin == pin)
                         return 0;
-                last = &entry->next;
-        }
 
         entry = alloc_irq_pin_list(node);
         if (!entry) {
@@ -479,22 +477,19 @@ static int __add_pin_to_irq_node(struct irq_cfg *cfg, int node, int apic, int pi
         entry->apic = apic;
         entry->pin = pin;
 
-        *last = entry;
+        list_add_tail(&entry->list, &cfg->irq_2_pin);
         return 0;
 }
 
 static void __remove_pin_from_irq(struct irq_cfg *cfg, int apic, int pin)
 {
-        struct irq_pin_list **last, *entry;
+        struct irq_pin_list *tmp, *entry;
 
-        last = &cfg->irq_2_pin;
-        for_each_irq_pin(entry, cfg->irq_2_pin)
+        list_for_each_entry_safe(entry, tmp, &cfg->irq_2_pin, list)
                 if (entry->apic == apic && entry->pin == pin) {
-                        *last = entry->next;
+                        list_del(&entry->list);
                         kfree(entry);
                         return;
-                } else {
-                        last = &entry->next;
                 }
 }
 
@@ -1739,8 +1734,7 @@ __apicdebuginit(void) print_IO_APICs(void)
                 cfg = irq_cfg(irq);
                 if (!cfg)
                         continue;
-                entry = cfg->irq_2_pin;
-                if (!entry)
+                if (list_empty(&cfg->irq_2_pin))
                         continue;
                 printk(KERN_DEBUG "IRQ%d ", irq);
                 for_each_irq_pin(entry, cfg->irq_2_pin)
@@ -4076,7 +4070,7 @@ void mp_irqdomain_unmap(struct irq_domain *domain, unsigned int virq)
 
         ioapic_mask_entry(ioapic, pin);
         __remove_pin_from_irq(cfg, ioapic, pin);
-        WARN_ON(cfg->irq_2_pin != NULL);
+        WARN_ON(!list_empty(&cfg->irq_2_pin));
         arch_teardown_hwirq(virq);
 }