pass struct irq_desc * to all other IRQ accessors

This is again because the descriptor is generally more useful (with
the IRQ number being accessible in it if necessary) and going forward
will hopefully allow to remove all direct accesses to the IRQ
descriptor array, in turn making it possible to make this some other,
more efficient data structure.

This additionally makes the .end() accessor optional, noting that in a
number of cases the functions were empty.

Signed-off-by: Jan Beulich <jbeulich@suse.com>

1 files changed, 12 insertions, 43 deletions

diff --git a/xen/arch/x86/hpet.c b/xen/arch/x86/hpet.c
index 7f179fe2ff..262ed0e439 100644
--- a/xen/arch/x86/hpet.c
+++ b/xen/arch/x86/hpet.c
@@ -49,9 +49,6 @@ static unsigned int __read_mostly num_hpets_used;
 
 DEFINE_PER_CPU(struct hpet_event_channel *, cpu_bc_channel);
 
-static unsigned int *__read_mostly irq_channel;
-#define irq_to_channel(irq)   irq_channel[irq]
-
 unsigned long __read_mostly hpet_address;
 
 /*
@@ -232,26 +229,20 @@ static void hpet_interrupt_handler(int irq, void *data,
     ch->event_handler(ch);
 }
 
-static void hpet_msi_unmask(unsigned int irq)
+static void hpet_msi_unmask(struct irq_desc *desc)
 {
     u32 cfg;
-    unsigned int ch_idx = irq_to_channel(irq);
-    struct hpet_event_channel *ch = hpet_events + ch_idx;
-
-    BUG_ON(ch_idx >= num_hpets_used);
+    struct hpet_event_channel *ch = desc->action->dev_id;
 
     cfg = hpet_read32(HPET_Tn_CFG(ch->idx));
     cfg |= HPET_TN_FSB;
     hpet_write32(cfg, HPET_Tn_CFG(ch->idx));
 }
 
-static void hpet_msi_mask(unsigned int irq)
+static void hpet_msi_mask(struct irq_desc *desc)
 {
     u32 cfg;
-    unsigned int ch_idx = irq_to_channel(irq);
-    struct hpet_event_channel *ch = hpet_events + ch_idx;
-
-    BUG_ON(ch_idx >= num_hpets_used);
+    struct hpet_event_channel *ch = desc->action->dev_id;
 
     cfg = hpet_read32(HPET_Tn_CFG(ch->idx));
     cfg &= ~HPET_TN_FSB;
@@ -271,30 +262,21 @@ static void hpet_msi_read(struct hpet_event_channel *ch, struct msi_msg *msg)
     msg->address_hi = 0;
 }
 
-static unsigned int hpet_msi_startup(unsigned int irq)
+static unsigned int hpet_msi_startup(struct irq_desc *desc)
 {
-    hpet_msi_unmask(irq);
+    hpet_msi_unmask(desc);
     return 0;
 }
 
-static void hpet_msi_shutdown(unsigned int irq)
-{
-    hpet_msi_mask(irq);
-}
+#define hpet_msi_shutdown hpet_msi_mask
 
-static void hpet_msi_ack(unsigned int irq)
+static void hpet_msi_ack(struct irq_desc *desc)
 {
-    struct irq_desc *desc = irq_to_desc(irq);
-
     irq_complete_move(desc);
-    move_native_irq(irq);
+    move_native_irq(desc);
     ack_APIC_irq();
 }
 
-static void hpet_msi_end(unsigned int irq, u8 vector)
-{
-}
-
 static void hpet_msi_set_affinity(struct irq_desc *desc, const cpumask_t *mask)
 {
     struct msi_msg msg;
@@ -323,7 +305,6 @@ static hw_irq_controller hpet_msi_type = {
     .enable	    = hpet_msi_unmask,
     .disable    = hpet_msi_mask,
     .ack        = hpet_msi_ack,
-    .end        = hpet_msi_end,
     .set_affinity   = hpet_msi_set_affinity,
 };
 
@@ -335,14 +316,13 @@ static void __hpet_setup_msi_irq(struct irq_desc *desc)
     hpet_msi_write(desc->action->dev_id, &msg);
 }
 
-static int __init hpet_setup_msi_irq(unsigned int irq)
+static int __init hpet_setup_msi_irq(unsigned int irq, struct hpet_event_channel *ch)
 {
     int ret;
     irq_desc_t *desc = irq_to_desc(irq);
 
     desc->handler = &hpet_msi_type;
-    ret = request_irq(irq, hpet_interrupt_handler,
-                      0, "HPET", hpet_events + irq_channel[irq]);
+    ret = request_irq(irq, hpet_interrupt_handler, 0, "HPET", ch);
     if ( ret < 0 )
         return ret;
 
@@ -358,12 +338,9 @@ static int __init hpet_assign_irq(unsigned int idx)
     if ( (irq = create_irq()) < 0 )
         return irq;
 
-    irq_channel[irq] = idx;
-
-    if ( hpet_setup_msi_irq(irq) )
+    if ( hpet_setup_msi_irq(irq, hpet_events + idx) )
     {
         destroy_irq(irq);
-        irq_channel[irq] = -1;
         return -EINVAL;
     }
 
@@ -511,11 +488,6 @@ void __init hpet_broadcast_init(void)
     if ( hpet_rate == 0 )
         return;
 
-    irq_channel = xmalloc_array(unsigned int, nr_irqs);
-    BUG_ON(irq_channel == NULL);
-    for ( i = 0; i < nr_irqs; i++ )
-        irq_channel[i] = -1;
-
     cfg = hpet_read32(HPET_CFG);
 
     hpet_fsb_cap_lookup();
@@ -527,9 +499,6 @@ void __init hpet_broadcast_init(void)
     }
     else
     {
-        xfree(irq_channel);
-        irq_channel = NULL;
-
         hpet_id = hpet_read32(HPET_ID);
         if ( !(hpet_id & HPET_ID_LEGSUP) )
             return;