This is just the first step; it'll take a lot of driver auditing before
we can change over to using NO_IRQ everywhere.
- Add a default definition of NO_IRQ to <linux/hardirq.h>
- Remove NO_IRQ definitions from all architectures which defined it
(since they all defined it to -1 anyway)
- Add a PCI_NO_IRQ to <linux/pci.h> so I don't have to touch all the
drivers at once
- Change pci/probe.c to use it (should have no effect)
- Convert pd6729 to use PCI_NO_IRQ instead of NO_IRQ
- Add checks in manage.c to do the right thing if an invalid irq (such
as NO_IRQ) is passed in
comments welcomed.
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 0057864..99681db 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -571,9 +571,12 @@ static void pci_read_irq(struct pci_dev
unsigned char irq;
pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
- if (irq)
+ if (irq) {
pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
- dev->irq = irq;
+ dev->irq = irq;
+ } else {
+ dev->irq = PCI_NO_IRQ;
+ }
}
/**
diff --git a/drivers/pcmcia/pd6729.c b/drivers/pcmcia/pd6729.c
index 20642f0..403d68b 100644
--- a/drivers/pcmcia/pd6729.c
+++ b/drivers/pcmcia/pd6729.c
@@ -39,10 +39,6 @@ MODULE_AUTHOR("Jun Komuro <komurojun-mbn
*/
#define to_cycles(ns) ((ns)/120)
-#ifndef NO_IRQ
-#define NO_IRQ ((unsigned int)(0))
-#endif
-
/*
* PARAMETERS
* irq_mode=n
@@ -733,7 +729,7 @@ static int __devinit pd6729_pci_probe(st
goto err_out_disable;
}
- if (dev->irq == NO_IRQ)
+ if (dev->irq == PCI_NO_IRQ)
irq_mode = 0; /* fall back to ISA interrupt mode */
mask = pd6729_isa_scan();
diff --git a/include/asm-arm/irq.h b/include/asm-arm/irq.h
index f97912f..11f35a0 100644
--- a/include/asm-arm/irq.h
+++ b/include/asm-arm/irq.h
@@ -11,14 +11,6 @@
#define NR_IRQS 128
#endif
-/*
- * Use this value to indicate lack of interrupt
- * capability
- */
-#ifndef NO_IRQ
-#define NO_IRQ ((unsigned int)(-1))
-#endif
-
struct irqaction;
extern void disable_irq_nosync(unsigned int);
diff --git a/include/asm-arm26/irq.h b/include/asm-arm26/irq.h
index 06bd5a5..7957d4e 100644
--- a/include/asm-arm26/irq.h
+++ b/include/asm-arm26/irq.h
@@ -14,14 +14,6 @@
#endif
-/*
- * Use this value to indicate lack of interrupt
- * capability
- */
-#ifndef NO_IRQ
-#define NO_IRQ ((unsigned int)(-1))
-#endif
-
struct irqaction;
#define disable_irq_nosync(i) disable_irq(i)
diff --git a/include/asm-frv/irq.h b/include/asm-frv/irq.h
index 2c16d8d..fbc5bd7 100644
--- a/include/asm-frv/irq.h
+++ b/include/asm-frv/irq.h
@@ -20,9 +20,6 @@
* drivers
*/
-/* this number is used when no interrupt has been assigned */
-#define NO_IRQ (-1)
-
#define NR_IRQ_LOG2_ACTIONS_PER_GROUP 5
#define NR_IRQ_ACTIONS_PER_GROUP (1 << NR_IRQ_LOG2_ACTIONS_PER_GROUP)
#define NR_IRQ_GROUPS 4
diff --git a/include/asm-parisc/irq.h b/include/asm-parisc/irq.h
index f876bdf..037ef9f 100644
--- a/include/asm-parisc/irq.h
+++ b/include/asm-parisc/irq.h
@@ -10,8 +10,6 @@
#include <linux/config.h>
#include <asm/types.h>
-#define NO_IRQ (-1)
-
#ifdef CONFIG_GSC
#define GSC_IRQ_BASE 16
#define GSC_IRQ_MAX 63
diff --git a/include/asm-ppc64/irq.h b/include/asm-ppc64/irq.h
index 99782af..d5739b7 100644
--- a/include/asm-ppc64/irq.h
+++ b/include/asm-ppc64/irq.h
@@ -17,9 +17,6 @@
*/
#define NR_IRQS 512
-/* this number is used when no interrupt has been assigned */
-#define NO_IRQ (-1)
-
/*
* These constants are used for passing information about interrupt
* signal polarity and level/edge sensing to the low-level PIC chip
diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h
index 5912874..f71a3ba 100644
--- a/include/linux/hardirq.h
+++ b/include/linux/hardirq.h
@@ -87,6 +87,16 @@ extern void synchronize_irq(unsigned int
# define synchronize_irq(irq) barrier()
#endif
+/*
+ * This value means "Device has no interrupt". For most pieces of code,
+ * any value above NR_IRQS would do, but -1 is traditional. The PCI
+ * subsystem used to use 0, but that's a legal IRQ number on some
+ * architectures.
+ */
+#ifndef NO_IRQ
+#define NO_IRQ ((unsigned int)(-1))
+#endif
+
#define nmi_enter() irq_enter()
#define nmi_exit() sub_preempt_count(HARDIRQ_OFFSET)
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 7349058..12f4317 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -139,6 +139,14 @@ struct pci_dev {
struct bin_attribute *res_attr[DEVICE_COUNT_RESOURCE]; /* sysfs file
for resources */
};
+/*
+ * The PCI subsystem has traditionally filled in 0 when no interrupt has been
+ * assigned. While we should move to using NO_IRQ instead, many drivers
+ * remain to be converted. Once all drivers are using PCI_NO_IRQ, switching
+ * over should be a simple search-and-replace.
+ */
+#define PCI_NO_IRQ 0
+
#define pci_dev_g(n) list_entry(n, struct pci_dev, global_list)
#define pci_dev_b(n) list_entry(n, struct pci_dev, bus_list)
#define to_pci_dev(n) container_of(n, struct pci_dev, dev)
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 1cfdb08..4190d9e 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -35,6 +35,9 @@ void synchronize_irq(unsigned int irq)
{
struct irq_desc *desc = irq_desc + irq;
+ if (irq >= NR_IRQS)
+ return;
+
while (desc->status & IRQ_INPROGRESS)
cpu_relax();
}
@@ -59,6 +62,9 @@ void disable_irq_nosync(unsigned int irq
irq_desc_t *desc = irq_desc + irq;
unsigned long flags;
+ if (irq >= NR_IRQS)
+ return;
+
spin_lock_irqsave(&desc->lock, flags);
if (!desc->depth++) {
desc->status |= IRQ_DISABLED;
@@ -85,6 +91,9 @@ void disable_irq(unsigned int irq)
{
irq_desc_t *desc = irq_desc + irq;
+ if (irq >= NR_IRQS)
+ return;
+
disable_irq_nosync(irq);
if (desc->action)
synchronize_irq(irq);
@@ -107,6 +116,9 @@ void enable_irq(unsigned int irq)
irq_desc_t *desc = irq_desc + irq;
unsigned long flags;
+ if (irq >= NR_IRQS)
+ return;
+
spin_lock_irqsave(&desc->lock, flags);
switch (desc->depth) {
case 0:
@@ -162,6 +174,9 @@ int setup_irq(unsigned int irq, struct i
unsigned long flags;
int shared = 0;
+ if (irq >= NR_IRQS)
+ return -EINVAL;
+
if (desc->handler == &no_irq_type)
return -ENOSYS;
/*
