Fedora kernel-2.6.17-1.2142_FC4 patched with stable patch-2.6.17.4-vs2.0.2-rc26.diff
[linux-2.6.git] / arch / ia64 / kernel / iosapic.c
index 88b0143..d58c1c5 100644 (file)
@@ -9,54 +9,65 @@
  * Copyright (C) 1999 VA Linux Systems
  * Copyright (C) 1999,2000 Walt Drummond <drummond@valinux.com>
  *
- * 00/04/19    D. Mosberger    Rewritten to mirror more closely the x86 I/O APIC code.
- *                             In particular, we now have separate handlers for edge
- *                             and level triggered interrupts.
- * 00/10/27    Asit Mallick, Goutham Rao <goutham.rao@intel.com> IRQ vector allocation
- *                             PCI to vector mapping, shared PCI interrupts.
- * 00/10/27    D. Mosberger    Document things a bit more to make them more understandable.
- *                             Clean up much of the old IOSAPIC cruft.
- * 01/07/27    J.I. Lee        PCI irq routing, Platform/Legacy interrupts and fixes for
- *                             ACPI S5(SoftOff) support.
+ * 00/04/19    D. Mosberger    Rewritten to mirror more closely the x86 I/O
+ *                             APIC code.  In particular, we now have separate
+ *                             handlers for edge and level triggered
+ *                             interrupts.
+ * 00/10/27    Asit Mallick, Goutham Rao <goutham.rao@intel.com> IRQ vector
+ *                             allocation PCI to vector mapping, shared PCI
+ *                             interrupts.
+ * 00/10/27    D. Mosberger    Document things a bit more to make them more
+ *                             understandable.  Clean up much of the old
+ *                             IOSAPIC cruft.
+ * 01/07/27    J.I. Lee        PCI irq routing, Platform/Legacy interrupts
+ *                             and fixes for ACPI S5(SoftOff) support.
  * 02/01/23    J.I. Lee        iosapic pgm fixes for PCI irq routing from _PRT
- * 02/01/07     E. Focht        <efocht@ess.nec.de> Redirectable interrupt vectors in
- *                              iosapic_set_affinity(), initializations for
- *                              /proc/irq/#/smp_affinity
+ * 02/01/07     E. Focht        <efocht@ess.nec.de> Redirectable interrupt
+ *                             vectors in iosapic_set_affinity(),
+ *                             initializations for /proc/irq/#/smp_affinity
  * 02/04/02    P. Diefenbaugh  Cleaned up ACPI PCI IRQ routing.
  * 02/04/18    J.I. Lee        bug fix in iosapic_init_pci_irq
- * 02/04/30    J.I. Lee        bug fix in find_iosapic to fix ACPI PCI IRQ to IOSAPIC mapping
- *                             error
+ * 02/04/30    J.I. Lee        bug fix in find_iosapic to fix ACPI PCI IRQ to
+ *                             IOSAPIC mapping error
  * 02/07/29    T. Kochi        Allocate interrupt vectors dynamically
- * 02/08/04    T. Kochi        Cleaned up terminology (irq, global system interrupt, vector, etc.)
- * 02/09/20    D. Mosberger    Simplified by taking advantage of ACPI's pci_irq code.
+ * 02/08/04    T. Kochi        Cleaned up terminology (irq, global system
+ *                             interrupt, vector, etc.)
+ * 02/09/20    D. Mosberger    Simplified by taking advantage of ACPI's
+ *                             pci_irq code.
  * 03/02/19    B. Helgaas      Make pcat_compat system-wide, not per-IOSAPIC.
- *                             Remove iosapic_address & gsi_base from external interfaces.
- *                             Rationalize __init/__devinit attributes.
+ *                             Remove iosapic_address & gsi_base from
+ *                             external interfaces.  Rationalize
+ *                             __init/__devinit attributes.
  * 04/12/04 Ashok Raj  <ashok.raj@intel.com> Intel Corporation 2004
- *                             Updated to work with irq migration necessary for CPU Hotplug
+ *                             Updated to work with irq migration necessary
+ *                             for CPU Hotplug
  */
 /*
- * Here is what the interrupt logic between a PCI device and the kernel looks like:
+ * Here is what the interrupt logic between a PCI device and the kernel looks
+ * like:
  *
- * (1) A PCI device raises one of the four interrupt pins (INTA, INTB, INTC, INTD).  The
- *     device is uniquely identified by its bus--, and slot-number (the function
- *     number does not matter here because all functions share the same interrupt
- *     lines).
+ * (1) A PCI device raises one of the four interrupt pins (INTA, INTB, INTC,
+ *     INTD).  The device is uniquely identified by its bus-, and slot-number
+ *     (the function number does not matter here because all functions share
+ *     the same interrupt lines).
  *
- * (2) The motherboard routes the interrupt line to a pin on a IOSAPIC controller.
- *     Multiple interrupt lines may have to share the same IOSAPIC pin (if they're level
- *     triggered and use the same polarity).  Each interrupt line has a unique Global
- *     System Interrupt (GSI) number which can be calculated as the sum of the controller's
- *     base GSI number and the IOSAPIC pin number to which the line connects.
+ * (2) The motherboard routes the interrupt line to a pin on a IOSAPIC
+ *     controller.  Multiple interrupt lines may have to share the same
+ *     IOSAPIC pin (if they're level triggered and use the same polarity).
+ *     Each interrupt line has a unique Global System Interrupt (GSI) number
+ *     which can be calculated as the sum of the controller's base GSI number
+ *     and the IOSAPIC pin number to which the line connects.
  *
- * (3) The IOSAPIC uses an internal routing table entries (RTEs) to map the IOSAPIC pin
- *     into the IA-64 interrupt vector.  This interrupt vector is then sent to the CPU.
+ * (3) The IOSAPIC uses an internal routing table entries (RTEs) to map the
+ * IOSAPIC pin into the IA-64 interrupt vector.  This interrupt vector is then
+ * sent to the CPU.
  *
- * (4) The kernel recognizes an interrupt as an IRQ.  The IRQ interface is used as
- *     architecture-independent interrupt handling mechanism in Linux.  As an
- *     IRQ is a number, we have to have IA-64 interrupt vector number <-> IRQ number
- *     mapping.  On smaller systems, we use one-to-one mapping between IA-64 vector and
- *     IRQ.  A platform can implement platform_irq_to_vector(irq) and
+ * (4) The kernel recognizes an interrupt as an IRQ.  The IRQ interface is
+ *     used as architecture-independent interrupt handling mechanism in Linux.
+ *     As an IRQ is a number, we have to have
+ *     IA-64 interrupt vector number <-> IRQ number mapping.  On smaller
+ *     systems, we use one-to-one mapping between IA-64 vector and IRQ.  A
+ *     platform can implement platform_irq_to_vector(irq) and
  *     platform_local_vector_to_irq(vector) APIs to differentiate the mapping.
  *     Please see also include/asm-ia64/hw_irq.h for those APIs.
  *
@@ -64,9 +75,9 @@
  *
  *     PCI pin -> global system interrupt (GSI) -> IA-64 vector <-> IRQ
  *
- * Note: The term "IRQ" is loosely used everywhere in Linux kernel to describe interrupts.
- * Now we use "IRQ" only for Linux IRQ's.  ISA IRQ (isa_irq) is the only exception in this
- * source code.
+ * Note: The term "IRQ" is loosely used everywhere in Linux kernel to
+ * describeinterrupts.  Now we use "IRQ" only for Linux IRQ's.  ISA IRQ
+ * (isa_irq) is the only exception in this source code.
  */
 #include <linux/config.h>
 
 #include <asm/ptrace.h>
 #include <asm/system.h>
 
-
 #undef DEBUG_INTERRUPT_ROUTING
 
 #ifdef DEBUG_INTERRUPT_ROUTING
 #define DBG(fmt...)
 #endif
 
-#define NR_PREALLOCATE_RTE_ENTRIES     (PAGE_SIZE / sizeof(struct iosapic_rte_info))
+#define NR_PREALLOCATE_RTE_ENTRIES \
+       (PAGE_SIZE / sizeof(struct iosapic_rte_info))
 #define RTE_PREALLOCATED       (1)
 
 static DEFINE_SPINLOCK(iosapic_lock);
 
-/* These tables map IA-64 vectors to the IOSAPIC pin that generates this vector. */
+/*
+ * These tables map IA-64 vectors to the IOSAPIC pin that generates this
+ * vector.
+ */
 
 struct iosapic_rte_info {
-       struct list_head rte_list;      /* node in list of RTEs sharing the same vector */
+       struct list_head rte_list;      /* node in list of RTEs sharing the
+                                        * same vector */
        char __iomem    *addr;          /* base address of IOSAPIC */
-       unsigned int    gsi_base;       /* first GSI assigned to this IOSAPIC */
+       unsigned int    gsi_base;       /* first GSI assigned to this
+                                        * IOSAPIC */
        char            rte_index;      /* IOSAPIC RTE index */
        int             refcnt;         /* reference counter */
        unsigned int    flags;          /* flags */
 } ____cacheline_aligned;
 
 static struct iosapic_intr_info {
-       struct list_head rtes;          /* RTEs using this vector (empty => not an IOSAPIC interrupt) */
+       struct list_head rtes;          /* RTEs using this vector (empty =>
+                                        * not an IOSAPIC interrupt) */
        int             count;          /* # of RTEs that shares this vector */
-       u32             low32;          /* current value of low word of Redirection table entry */
+       u32             low32;          /* current value of low word of
+                                        * Redirection table entry */
        unsigned int    dest;           /* destination CPU physical ID */
        unsigned char   dmode   : 3;    /* delivery mode (see iosapic.h) */
-       unsigned char   polarity: 1;    /* interrupt polarity (see iosapic.h) */
+       unsigned char   polarity: 1;    /* interrupt polarity
+                                        * (see iosapic.h) */
        unsigned char   trigger : 1;    /* trigger mode (see iosapic.h) */
 } iosapic_intr_info[IA64_NUM_VECTORS];
 
 static struct iosapic {
        char __iomem    *addr;          /* base address of IOSAPIC */
-       unsigned int    gsi_base;       /* first GSI assigned to this IOSAPIC */
-       unsigned short  num_rte;        /* number of RTE in this IOSAPIC */
+       unsigned int    gsi_base;       /* first GSI assigned to this
+                                        * IOSAPIC */
+       unsigned short  num_rte;        /* # of RTEs on this IOSAPIC */
+       int             rtes_inuse;     /* # of RTEs in use on this IOSAPIC */
 #ifdef CONFIG_NUMA
        unsigned short  node;           /* numa node association via pxm */
 #endif
 } iosapic_lists[NR_IOSAPICS];
 
-static int num_iosapic;
-
-static unsigned char pcat_compat __initdata;   /* 8259 compatibility flag */
+static unsigned char pcat_compat __devinitdata;        /* 8259 compatibility flag */
 
 static int iosapic_kmalloc_ok;
 static LIST_HEAD(free_rte_list);
@@ -149,8 +168,9 @@ find_iosapic (unsigned int gsi)
 {
        int i;
 
-       for (i = 0; i < num_iosapic; i++) {
-               if ((unsigned) (gsi - iosapic_lists[i].gsi_base) < iosapic_lists[i].num_rte)
+       for (i = 0; i < NR_IOSAPICS; i++) {
+               if ((unsigned) (gsi - iosapic_lists[i].gsi_base) <
+                   iosapic_lists[i].num_rte)
                        return i;
        }
 
@@ -163,7 +183,8 @@ _gsi_to_vector (unsigned int gsi)
        struct iosapic_intr_info *info;
        struct iosapic_rte_info *rte;
 
-       for (info = iosapic_intr_info; info < iosapic_intr_info + IA64_NUM_VECTORS; ++info)
+       for (info = iosapic_intr_info; info <
+                    iosapic_intr_info + IA64_NUM_VECTORS; ++info)
                list_for_each_entry(rte, &info->rtes, rte_list)
                        if (rte->gsi_base + rte->rte_index == gsi)
                                return info - iosapic_intr_info;
@@ -186,8 +207,8 @@ gsi_to_irq (unsigned int gsi)
        unsigned long flags;
        int irq;
        /*
-        * XXX fix me: this assumes an identity mapping vetween IA-64 vector and Linux irq
-        * numbers...
+        * XXX fix me: this assumes an identity mapping between IA-64 vector
+        * and Linux irq numbers...
         */
        spin_lock_irqsave(&iosapic_lock, flags);
        {
@@ -198,7 +219,8 @@ gsi_to_irq (unsigned int gsi)
        return irq;
 }
 
-static struct iosapic_rte_info *gsi_vector_to_rte(unsigned int gsi, unsigned int vec)
+static struct iosapic_rte_info *gsi_vector_to_rte(unsigned int gsi,
+                                                 unsigned int vec)
 {
        struct iosapic_rte_info *rte;
 
@@ -238,7 +260,9 @@ set_rte (unsigned int gsi, unsigned int vector, unsigned int dest, int mask)
 
                for (irq = 0; irq < NR_IRQS; ++irq)
                        if (irq_to_vector(irq) == vector) {
-                               set_irq_affinity_info(irq, (int)(dest & 0xffff), redir);
+                               set_irq_affinity_info(irq,
+                                                     (int)(dest & 0xffff),
+                                                     redir);
                                break;
                        }
        }
@@ -260,7 +284,7 @@ set_rte (unsigned int gsi, unsigned int vector, unsigned int dest, int mask)
 }
 
 static void
-nop (unsigned int vector)
+nop (unsigned int irq)
 {
        /* do nothing... */
 }
@@ -282,7 +306,8 @@ mask_irq (unsigned int irq)
        {
                /* set only the mask bit */
                low32 = iosapic_intr_info[vec].low32 |= IOSAPIC_MASK;
-               list_for_each_entry(rte, &iosapic_intr_info[vec].rtes, rte_list) {
+               list_for_each_entry(rte, &iosapic_intr_info[vec].rtes,
+                                   rte_list) {
                        addr = rte->addr;
                        rte_index = rte->rte_index;
                        iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
@@ -307,7 +332,8 @@ unmask_irq (unsigned int irq)
        spin_lock_irqsave(&iosapic_lock, flags);
        {
                low32 = iosapic_intr_info[vec].low32 &= ~IOSAPIC_MASK;
-               list_for_each_entry(rte, &iosapic_intr_info[vec].rtes, rte_list) {
+               list_for_each_entry(rte, &iosapic_intr_info[vec].rtes,
+                                   rte_list) {
                        addr = rte->addr;
                        rte_index = rte->rte_index;
                        iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
@@ -347,21 +373,25 @@ iosapic_set_affinity (unsigned int irq, cpumask_t mask)
 
        spin_lock_irqsave(&iosapic_lock, flags);
        {
-               low32 = iosapic_intr_info[vec].low32 & ~(7 << IOSAPIC_DELIVERY_SHIFT);
+               low32 = iosapic_intr_info[vec].low32 &
+                       ~(7 << IOSAPIC_DELIVERY_SHIFT);
 
                if (redir)
                        /* change delivery mode to lowest priority */
-                       low32 |= (IOSAPIC_LOWEST_PRIORITY << IOSAPIC_DELIVERY_SHIFT);
+                       low32 |= (IOSAPIC_LOWEST_PRIORITY <<
+                                 IOSAPIC_DELIVERY_SHIFT);
                else
                        /* change delivery mode to fixed */
                        low32 |= (IOSAPIC_FIXED << IOSAPIC_DELIVERY_SHIFT);
 
                iosapic_intr_info[vec].low32 = low32;
                iosapic_intr_info[vec].dest = dest;
-               list_for_each_entry(rte, &iosapic_intr_info[vec].rtes, rte_list) {
+               list_for_each_entry(rte, &iosapic_intr_info[vec].rtes,
+                                   rte_list) {
                        addr = rte->addr;
                        rte_index = rte->rte_index;
-                       iosapic_write(addr, IOSAPIC_RTE_HIGH(rte_index), high32);
+                       iosapic_write(addr, IOSAPIC_RTE_HIGH(rte_index),
+                                     high32);
                        iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
                }
        }
@@ -386,7 +416,7 @@ iosapic_end_level_irq (unsigned int irq)
        ia64_vector vec = irq_to_vector(irq);
        struct iosapic_rte_info *rte;
 
-       move_irq(irq);
+       move_native_irq(irq);
        list_for_each_entry(rte, &iosapic_intr_info[vec].rtes, rte_list)
                iosapic_eoi(rte->addr, vec);
 }
@@ -428,13 +458,14 @@ iosapic_ack_edge_irq (unsigned int irq)
 {
        irq_desc_t *idesc = irq_descp(irq);
 
-       move_irq(irq);
+       move_native_irq(irq);
        /*
         * Once we have recorded IRQ_PENDING already, we can mask the
         * interrupt for real. This prevents IRQ storms from unhandled
         * devices.
         */
-       if ((idesc->status & (IRQ_PENDING|IRQ_DISABLED)) == (IRQ_PENDING|IRQ_DISABLED))
+       if ((idesc->status & (IRQ_PENDING|IRQ_DISABLED)) ==
+           (IRQ_PENDING|IRQ_DISABLED))
                mask_irq(irq);
 }
 
@@ -468,7 +499,8 @@ iosapic_version (char __iomem *addr)
        return iosapic_read(addr, IOSAPIC_VERSION);
 }
 
-static int iosapic_find_sharable_vector (unsigned long trigger, unsigned long pol)
+static int iosapic_find_sharable_vector (unsigned long trigger,
+                                        unsigned long pol)
 {
        int i, vector = -1, min_count = -1;
        struct iosapic_intr_info *info;
@@ -483,15 +515,14 @@ static int iosapic_find_sharable_vector (unsigned long trigger, unsigned long po
        for (i = IA64_FIRST_DEVICE_VECTOR; i <= IA64_LAST_DEVICE_VECTOR; i++) {
                info = &iosapic_intr_info[i];
                if (info->trigger == trigger && info->polarity == pol &&
-                   (info->dmode == IOSAPIC_FIXED || info->dmode == IOSAPIC_LOWEST_PRIORITY)) {
+                   (info->dmode == IOSAPIC_FIXED || info->dmode ==
+                    IOSAPIC_LOWEST_PRIORITY)) {
                        if (min_count == -1 || info->count < min_count) {
                                vector = i;
                                min_count = info->count;
                        }
                }
        }
-       if (vector < 0)
-               panic("%s: out of interrupt vectors!\n", __FUNCTION__);
 
        return vector;
 }
@@ -507,12 +538,17 @@ iosapic_reassign_vector (int vector)
 
        if (!list_empty(&iosapic_intr_info[vector].rtes)) {
                new_vector = assign_irq_vector(AUTO_ASSIGN);
-               printk(KERN_INFO "Reassigning vector %d to %d\n", vector, new_vector);
+               if (new_vector < 0)
+                       panic("%s: out of interrupt vectors!\n", __FUNCTION__);
+               printk(KERN_INFO "Reassigning vector %d to %d\n",
+                      vector, new_vector);
                memcpy(&iosapic_intr_info[new_vector], &iosapic_intr_info[vector],
                       sizeof(struct iosapic_intr_info));
                INIT_LIST_HEAD(&iosapic_intr_info[new_vector].rtes);
-               list_move(iosapic_intr_info[vector].rtes.next, &iosapic_intr_info[new_vector].rtes);
-               memset(&iosapic_intr_info[vector], 0, sizeof(struct iosapic_intr_info));
+               list_move(iosapic_intr_info[vector].rtes.next,
+                         &iosapic_intr_info[new_vector].rtes);
+               memset(&iosapic_intr_info[vector], 0,
+                      sizeof(struct iosapic_intr_info));
                iosapic_intr_info[vector].low32 = IOSAPIC_MASK;
                INIT_LIST_HEAD(&iosapic_intr_info[vector].rtes);
        }
@@ -525,7 +561,8 @@ static struct iosapic_rte_info *iosapic_alloc_rte (void)
        int preallocated = 0;
 
        if (!iosapic_kmalloc_ok && list_empty(&free_rte_list)) {
-               rte = alloc_bootmem(sizeof(struct iosapic_rte_info) * NR_PREALLOCATE_RTE_ENTRIES);
+               rte = alloc_bootmem(sizeof(struct iosapic_rte_info) *
+                                   NR_PREALLOCATE_RTE_ENTRIES);
                if (!rte)
                        return NULL;
                for (i = 0; i < NR_PREALLOCATE_RTE_ENTRIES; i++, rte++)
@@ -533,7 +570,8 @@ static struct iosapic_rte_info *iosapic_alloc_rte (void)
        }
 
        if (!list_empty(&free_rte_list)) {
-               rte = list_entry(free_rte_list.next, struct iosapic_rte_info, rte_list);
+               rte = list_entry(free_rte_list.next, struct iosapic_rte_info,
+                                rte_list);
                list_del(&rte->rte_list);
                preallocated++;
        } else {
@@ -562,7 +600,7 @@ static inline int vector_is_shared (int vector)
        return (iosapic_intr_info[vector].count > 1);
 }
 
-static void
+static int
 register_intr (unsigned int gsi, int vector, unsigned char delivery,
               unsigned long polarity, unsigned long trigger)
 {
@@ -576,8 +614,9 @@ register_intr (unsigned int gsi, int vector, unsigned char delivery,
 
        index = find_iosapic(gsi);
        if (index < 0) {
-               printk(KERN_WARNING "%s: No IOSAPIC for GSI %u\n", __FUNCTION__, gsi);
-               return;
+               printk(KERN_WARNING "%s: No IOSAPIC for GSI %u\n",
+                      __FUNCTION__, gsi);
+               return -ENODEV;
        }
 
        iosapic_address = iosapic_lists[index].addr;
@@ -587,8 +626,9 @@ register_intr (unsigned int gsi, int vector, unsigned char delivery,
        if (!rte) {
                rte = iosapic_alloc_rte();
                if (!rte) {
-                       printk(KERN_WARNING "%s: cannot allocate memory\n", __FUNCTION__);
-                       return;
+                       printk(KERN_WARNING "%s: cannot allocate memory\n",
+                              __FUNCTION__);
+                       return -ENOMEM;
                }
 
                rte_index = gsi - gsi_base;
@@ -598,12 +638,15 @@ register_intr (unsigned int gsi, int vector, unsigned char delivery,
                rte->refcnt++;
                list_add_tail(&rte->rte_list, &iosapic_intr_info[vector].rtes);
                iosapic_intr_info[vector].count++;
+               iosapic_lists[index].rtes_inuse++;
        }
        else if (vector_is_shared(vector)) {
                struct iosapic_intr_info *info = &iosapic_intr_info[vector];
                if (info->trigger != trigger || info->polarity != polarity) {
-                       printk (KERN_WARNING "%s: cannot override the interrupt\n", __FUNCTION__);
-                       return;
+                       printk (KERN_WARNING
+                               "%s: cannot override the interrupt\n",
+                               __FUNCTION__);
+                       return -EINVAL;
                }
        }
 
@@ -619,10 +662,13 @@ register_intr (unsigned int gsi, int vector, unsigned char delivery,
        idesc = irq_descp(vector);
        if (idesc->handler != irq_type) {
                if (idesc->handler != &no_irq_type)
-                       printk(KERN_WARNING "%s: changing vector %d from %s to %s\n",
-                              __FUNCTION__, vector, idesc->handler->typename, irq_type->typename);
+                       printk(KERN_WARNING
+                              "%s: changing vector %d from %s to %s\n",
+                              __FUNCTION__, vector,
+                              idesc->handler->typename, irq_type->typename);
                idesc->handler = irq_type;
        }
+       return 0;
 }
 
 static unsigned int
@@ -630,6 +676,7 @@ get_target_cpu (unsigned int gsi, int vector)
 {
 #ifdef CONFIG_SMP
        static int cpu = -1;
+       extern int cpe_vector;
 
        /*
         * In case of vector shared by multiple RTEs, all RTEs that
@@ -652,6 +699,11 @@ get_target_cpu (unsigned int gsi, int vector)
        if (!cpu_online(smp_processor_id()))
                return cpu_physical_id(smp_processor_id());
 
+#ifdef CONFIG_ACPI
+       if (cpe_vector > 0 && vector == IA64_CPEP_VECTOR)
+               return get_cpei_target_cpu();
+#endif
+
 #ifdef CONFIG_NUMA
        {
                int num_cpus, cpu_index, iosapic_index, numa_cpu, i = 0;
@@ -674,7 +726,7 @@ get_target_cpu (unsigned int gsi, int vector)
                if (!num_cpus)
                        goto skip_numa_setup;
 
-               /* Use vector assigment to distribute across cpus in node */
+               /* Use vector assignment to distribute across cpus in node */
                cpu_index = vector % num_cpus;
 
                for (numa_cpu = first_cpu(cpu_mask) ; i < cpu_index ; i++)
@@ -696,7 +748,7 @@ skip_numa_setup:
        } while (!cpu_online(cpu));
 
        return cpu_physical_id(cpu);
-#else
+#else  /* CONFIG_SMP */
        return cpu_physical_id(smp_processor_id());
 #endif
 }
@@ -710,7 +762,7 @@ int
 iosapic_register_intr (unsigned int gsi,
                       unsigned long polarity, unsigned long trigger)
 {
-       int vector, mask = 1;
+       int vector, mask = 1, err;
        unsigned int dest;
        unsigned long flags;
        struct iosapic_rte_info *rte;
@@ -734,9 +786,12 @@ again:
        spin_unlock_irqrestore(&iosapic_lock, flags);
 
        /* If vector is running out, we try to find a sharable vector */
-       vector = assign_irq_vector_nopanic(AUTO_ASSIGN);
-       if (vector < 0)
+       vector = assign_irq_vector(AUTO_ASSIGN);
+       if (vector < 0) {
                vector = iosapic_find_sharable_vector(trigger, polarity);
+               if (vector < 0)
+                       return -ENOSPC;
+       }
 
        spin_lock_irqsave(&irq_descp(vector)->lock, flags);
        spin_lock(&iosapic_lock);
@@ -745,13 +800,20 @@ again:
                        if (list_empty(&iosapic_intr_info[vector].rtes))
                                free_irq_vector(vector);
                        spin_unlock(&iosapic_lock);
-                       spin_unlock_irqrestore(&irq_descp(vector)->lock, flags);
+                       spin_unlock_irqrestore(&irq_descp(vector)->lock,
+                                              flags);
                        goto again;
                }
 
                dest = get_target_cpu(gsi, vector);
-               register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY,
+               err = register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY,
                              polarity, trigger);
+               if (err < 0) {
+                       spin_unlock(&iosapic_lock);
+                       spin_unlock_irqrestore(&irq_descp(vector)->lock,
+                                              flags);
+                       return err;
+               }
 
                /*
                 * If the vector is shared and already unmasked for
@@ -773,12 +835,11 @@ again:
        return vector;
 }
 
-#ifdef CONFIG_ACPI_DEALLOCATE_IRQ
 void
 iosapic_unregister_intr (unsigned int gsi)
 {
        unsigned long flags;
-       int irq, vector;
+       int irq, vector, index;
        irq_desc_t *idesc;
        u32 low32;
        unsigned long trigger, polarity;
@@ -792,7 +853,8 @@ iosapic_unregister_intr (unsigned int gsi)
         */
        irq = gsi_to_irq(gsi);
        if (irq < 0) {
-               printk(KERN_ERR "iosapic_unregister_intr(%u) unbalanced\n", gsi);
+               printk(KERN_ERR "iosapic_unregister_intr(%u) unbalanced\n",
+                      gsi);
                WARN_ON(1);
                return;
        }
@@ -803,7 +865,9 @@ iosapic_unregister_intr (unsigned int gsi)
        spin_lock(&iosapic_lock);
        {
                if ((rte = gsi_vector_to_rte(gsi, vector)) == NULL) {
-                       printk(KERN_ERR "iosapic_unregister_intr(%u) unbalanced\n", gsi);
+                       printk(KERN_ERR
+                              "iosapic_unregister_intr(%u) unbalanced\n",
+                              gsi);
                        WARN_ON(1);
                        goto out;
                }
@@ -813,17 +877,23 @@ iosapic_unregister_intr (unsigned int gsi)
 
                /* Mask the interrupt */
                low32 = iosapic_intr_info[vector].low32 | IOSAPIC_MASK;
-               iosapic_write(rte->addr, IOSAPIC_RTE_LOW(rte->rte_index), low32);
+               iosapic_write(rte->addr, IOSAPIC_RTE_LOW(rte->rte_index),
+                             low32);
 
                /* Remove the rte entry from the list */
                list_del(&rte->rte_list);
                iosapic_intr_info[vector].count--;
                iosapic_free_rte(rte);
+               index = find_iosapic(gsi);
+               iosapic_lists[index].rtes_inuse--;
+               WARN_ON(iosapic_lists[index].rtes_inuse < 0);
 
                trigger  = iosapic_intr_info[vector].trigger;
                polarity = iosapic_intr_info[vector].polarity;
                dest     = iosapic_intr_info[vector].dest;
-               printk(KERN_INFO "GSI %u (%s, %s) -> CPU %d (0x%04x) vector %d unregistered\n",
+               printk(KERN_INFO
+                      "GSI %u (%s, %s) -> CPU %d (0x%04x)"
+                      " vector %d unregistered\n",
                       gsi, (trigger == IOSAPIC_EDGE ? "edge" : "level"),
                       (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
                       cpu_logical_id(dest), dest, vector);
@@ -836,12 +906,15 @@ iosapic_unregister_intr (unsigned int gsi)
                        idesc->handler = &no_irq_type;
 
                        /* Clear the interrupt information */
-                       memset(&iosapic_intr_info[vector], 0, sizeof(struct iosapic_intr_info));
+                       memset(&iosapic_intr_info[vector], 0,
+                              sizeof(struct iosapic_intr_info));
                        iosapic_intr_info[vector].low32 |= IOSAPIC_MASK;
                        INIT_LIST_HEAD(&iosapic_intr_info[vector].rtes);
 
                        if (idesc->action) {
-                               printk(KERN_ERR "interrupt handlers still exist on IRQ %u\n", irq);
+                               printk(KERN_ERR
+                                      "interrupt handlers still exist on"
+                                      "IRQ %u\n", irq);
                                WARN_ON(1);
                        }
 
@@ -853,11 +926,9 @@ iosapic_unregister_intr (unsigned int gsi)
        spin_unlock(&iosapic_lock);
        spin_unlock_irqrestore(&idesc->lock, flags);
 }
-#endif /* CONFIG_ACPI_DEALLOCATE_IRQ */
 
 /*
  * ACPI calls this when it finds an entry for a platform interrupt.
- * Note that the irq_base and IOSAPIC address must be set in iosapic_init().
  */
 int __init
 iosapic_register_platform_intr (u32 int_type, unsigned int gsi,
@@ -881,6 +952,8 @@ iosapic_register_platform_intr (u32 int_type, unsigned int gsi,
                break;
              case ACPI_INTERRUPT_INIT:
                vector = assign_irq_vector(AUTO_ASSIGN);
+               if (vector < 0)
+                       panic("%s: out of interrupt vectors!\n", __FUNCTION__);
                delivery = IOSAPIC_INIT;
                break;
              case ACPI_INTERRUPT_CPEI:
@@ -889,13 +962,16 @@ iosapic_register_platform_intr (u32 int_type, unsigned int gsi,
                mask = 1;
                break;
              default:
-               printk(KERN_ERR "iosapic_register_platform_irq(): invalid int type 0x%x\n", int_type);
+               printk(KERN_ERR "%s: invalid int type 0x%x\n", __FUNCTION__,
+                      int_type);
                return -1;
        }
 
        register_intr(gsi, vector, delivery, polarity, trigger);
 
-       printk(KERN_INFO "PLATFORM int %s (0x%x): GSI %u (%s, %s) -> CPU %d (0x%04x) vector %d\n",
+       printk(KERN_INFO
+              "PLATFORM int %s (0x%x): GSI %u (%s, %s) -> CPU %d (0x%04x)"
+              " vector %d\n",
               int_type < ARRAY_SIZE(name) ? name[int_type] : "unknown",
               int_type, gsi, (trigger == IOSAPIC_EDGE ? "edge" : "level"),
               (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
@@ -905,10 +981,8 @@ iosapic_register_platform_intr (u32 int_type, unsigned int gsi,
        return vector;
 }
 
-
 /*
  * ACPI calls this when it finds an entry for a legacy ISA IRQ override.
- * Note that the gsi_base and IOSAPIC address must be set in iosapic_init().
  */
 void __init
 iosapic_override_isa_irq (unsigned int isa_irq, unsigned int gsi,
@@ -937,59 +1011,151 @@ iosapic_system_init (int system_pcat_compat)
 
        for (vector = 0; vector < IA64_NUM_VECTORS; ++vector) {
                iosapic_intr_info[vector].low32 = IOSAPIC_MASK;
-               INIT_LIST_HEAD(&iosapic_intr_info[vector].rtes);        /* mark as unused */
+               /* mark as unused */
+               INIT_LIST_HEAD(&iosapic_intr_info[vector].rtes);
        }
 
        pcat_compat = system_pcat_compat;
        if (pcat_compat) {
                /*
-                * Disable the compatibility mode interrupts (8259 style), needs IN/OUT support
-                * enabled.
+                * Disable the compatibility mode interrupts (8259 style),
+                * needs IN/OUT support enabled.
                 */
-               printk(KERN_INFO "%s: Disabling PC-AT compatible 8259 interrupts\n", __FUNCTION__);
+               printk(KERN_INFO
+                      "%s: Disabling PC-AT compatible 8259 interrupts\n",
+                      __FUNCTION__);
                outb(0xff, 0xA1);
                outb(0xff, 0x21);
        }
 }
 
-void __init
+static inline int
+iosapic_alloc (void)
+{
+       int index;
+
+       for (index = 0; index < NR_IOSAPICS; index++)
+               if (!iosapic_lists[index].addr)
+                       return index;
+
+       printk(KERN_WARNING "%s: failed to allocate iosapic\n", __FUNCTION__);
+       return -1;
+}
+
+static inline void
+iosapic_free (int index)
+{
+       memset(&iosapic_lists[index], 0, sizeof(iosapic_lists[0]));
+}
+
+static inline int
+iosapic_check_gsi_range (unsigned int gsi_base, unsigned int ver)
+{
+       int index;
+       unsigned int gsi_end, base, end;
+
+       /* check gsi range */
+       gsi_end = gsi_base + ((ver >> 16) & 0xff);
+       for (index = 0; index < NR_IOSAPICS; index++) {
+               if (!iosapic_lists[index].addr)
+                       continue;
+
+               base = iosapic_lists[index].gsi_base;
+               end  = base + iosapic_lists[index].num_rte - 1;
+
+               if (gsi_end < base || end < gsi_base)
+                       continue; /* OK */
+
+               return -EBUSY;
+       }
+       return 0;
+}
+
+int __devinit
 iosapic_init (unsigned long phys_addr, unsigned int gsi_base)
 {
-       int num_rte;
+       int num_rte, err, index;
        unsigned int isa_irq, ver;
        char __iomem *addr;
+       unsigned long flags;
 
-       addr = ioremap(phys_addr, 0);
-       ver = iosapic_version(addr);
+       spin_lock_irqsave(&iosapic_lock, flags);
+       {
+               addr = ioremap(phys_addr, 0);
+               ver = iosapic_version(addr);
 
-       /*
-        * The MAX_REDIR register holds the highest input pin
-        * number (starting from 0).
-        * We add 1 so that we can use it for number of pins (= RTEs)
-        */
-       num_rte = ((ver >> 16) & 0xff) + 1;
+               if ((err = iosapic_check_gsi_range(gsi_base, ver))) {
+                       iounmap(addr);
+                       spin_unlock_irqrestore(&iosapic_lock, flags);
+                       return err;
+               }
+
+               /*
+                * The MAX_REDIR register holds the highest input pin
+                * number (starting from 0).
+                * We add 1 so that we can use it for number of pins (= RTEs)
+                */
+               num_rte = ((ver >> 16) & 0xff) + 1;
 
-       iosapic_lists[num_iosapic].addr = addr;
-       iosapic_lists[num_iosapic].gsi_base = gsi_base;
-       iosapic_lists[num_iosapic].num_rte = num_rte;
+               index = iosapic_alloc();
+               iosapic_lists[index].addr = addr;
+               iosapic_lists[index].gsi_base = gsi_base;
+               iosapic_lists[index].num_rte = num_rte;
 #ifdef CONFIG_NUMA
-       iosapic_lists[num_iosapic].node = MAX_NUMNODES;
+               iosapic_lists[index].node = MAX_NUMNODES;
 #endif
-       num_iosapic++;
+       }
+       spin_unlock_irqrestore(&iosapic_lock, flags);
 
        if ((gsi_base == 0) && pcat_compat) {
                /*
-                * Map the legacy ISA devices into the IOSAPIC data.  Some of these may
-                * get reprogrammed later on with data from the ACPI Interrupt Source
-                * Override table.
+                * Map the legacy ISA devices into the IOSAPIC data.  Some of
+                * these may get reprogrammed later on with data from the ACPI
+                * Interrupt Source Override table.
                 */
                for (isa_irq = 0; isa_irq < 16; ++isa_irq)
-                       iosapic_override_isa_irq(isa_irq, isa_irq, IOSAPIC_POL_HIGH, IOSAPIC_EDGE);
+                       iosapic_override_isa_irq(isa_irq, isa_irq,
+                                                IOSAPIC_POL_HIGH,
+                                                IOSAPIC_EDGE);
        }
+       return 0;
 }
 
+#ifdef CONFIG_HOTPLUG
+int
+iosapic_remove (unsigned int gsi_base)
+{
+       int index, err = 0;
+       unsigned long flags;
+
+       spin_lock_irqsave(&iosapic_lock, flags);
+       {
+               index = find_iosapic(gsi_base);
+               if (index < 0) {
+                       printk(KERN_WARNING "%s: No IOSAPIC for GSI base %u\n",
+                              __FUNCTION__, gsi_base);
+                       goto out;
+               }
+
+               if (iosapic_lists[index].rtes_inuse) {
+                       err = -EBUSY;
+                       printk(KERN_WARNING
+                              "%s: IOSAPIC for GSI base %u is busy\n",
+                              __FUNCTION__, gsi_base);
+                       goto out;
+               }
+
+               iounmap(iosapic_lists[index].addr);
+               iosapic_free(index);
+       }
+ out:
+       spin_unlock_irqrestore(&iosapic_lock, flags);
+       return err;
+}
+#endif /* CONFIG_HOTPLUG */
+
 #ifdef CONFIG_NUMA
-void __init
+void __devinit
 map_iosapic_to_node(unsigned int gsi_base, int node)
 {
        int index;