[PATCH] genirq: msi: refactor the msi_ops

The current msi_ops are short sighted in a number of ways, this patch attempts
to fix the glaring deficiences.

- Report in msi_ops if a 64bit address is needed in the msi message, so we
  can fail 32bit only msi structures.

- Send and receive a full struct msi_msg in both setup and target.  This is
  a little cleaner and allows for architectures that need to modify the data
  to retarget the msi interrupt to a different cpu.

- In target pass in the full cpu mask instead of just the first cpu in case
  we can make use of the full cpu mask.

- Operate in terms of irqs and not vectors, currently there is still a 1-1
  relationship but on architectures other than ia64 I expect this will change.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

5 files changed, 116 insertions, 115 deletions

diff --git a/drivers/pci/msi-altix.c b/drivers/pci/msi-altix.c
index bed4183a5e39..7aedc2ac8c28 100644
--- a/drivers/pci/msi-altix.c
+++ b/drivers/pci/msi-altix.c
@@ -26,7 +26,7 @@ struct sn_msi_info {
 static struct sn_msi_info *sn_msi_info;
 
 static void
-sn_msi_teardown(unsigned int vector)
+sn_msi_teardown(unsigned int irq)
 {
         nasid_t nasid;
         int widget;
@@ -36,7 +36,7 @@ sn_msi_teardown(unsigned int vector)
         struct pcibus_bussoft *bussoft;
         struct sn_pcibus_provider *provider;
 
-        sn_irq_info = sn_msi_info[vector].sn_irq_info;
+        sn_irq_info = sn_msi_info[irq].sn_irq_info;
         if (sn_irq_info == NULL || sn_irq_info->irq_int_bit >= 0)
                 return;
 
@@ -45,9 +45,9 @@ sn_msi_teardown(unsigned int vector)
         provider = SN_PCIDEV_BUSPROVIDER(pdev);
 
         (*provider->dma_unmap)(pdev,
-                               sn_msi_info[vector].pci_addr,
+                               sn_msi_info[irq].pci_addr,
                                PCI_DMA_FROMDEVICE);
-        sn_msi_info[vector].pci_addr = 0;
+        sn_msi_info[irq].pci_addr = 0;
 
         bussoft = SN_PCIDEV_BUSSOFT(pdev);
         nasid = NASID_GET(bussoft->bs_base);
@@ -56,14 +56,13 @@ sn_msi_teardown(unsigned int vector)
                         SWIN_WIDGETNUM(bussoft->bs_base);
 
         sn_intr_free(nasid, widget, sn_irq_info);
-        sn_msi_info[vector].sn_irq_info = NULL;
+        sn_msi_info[irq].sn_irq_info = NULL;
 
         return;
 }
 
 int
-sn_msi_setup(struct pci_dev *pdev, unsigned int vector,
-             u32 *addr_hi, u32 *addr_lo, u32 *data)
+sn_msi_setup(struct pci_dev *pdev, unsigned int irq, struct msi_msg *msg)
 {
         int widget;
         int status;
@@ -93,7 +92,7 @@ sn_msi_setup(struct pci_dev *pdev, unsigned int vector,
         if (! sn_irq_info)
                 return -ENOMEM;
 
-        status = sn_intr_alloc(nasid, widget, sn_irq_info, vector, -1, -1);
+        status = sn_intr_alloc(nasid, widget, sn_irq_info, irq, -1, -1);
         if (status) {
                 kfree(sn_irq_info);
                 return -ENOMEM;
@@ -119,28 +118,27 @@ sn_msi_setup(struct pci_dev *pdev, unsigned int vector,
                 return -ENOMEM;
         }
 
-        sn_msi_info[vector].sn_irq_info = sn_irq_info;
-        sn_msi_info[vector].pci_addr = bus_addr;
+        sn_msi_info[irq].sn_irq_info = sn_irq_info;
+        sn_msi_info[irq].pci_addr = bus_addr;
 
-        *addr_hi = (u32)(bus_addr >> 32);
-        *addr_lo = (u32)(bus_addr & 0x00000000ffffffff);
+        msg->address_hi = (u32)(bus_addr >> 32);
+        msg->address_lo = (u32)(bus_addr & 0x00000000ffffffff);
 
         /*
          * In the SN platform, bit 16 is a "send vector" bit which
          * must be present in order to move the vector through the system.
          */
-        *data = 0x100 + (unsigned int)vector;
+        msg->data = 0x100 + irq;
 
 #ifdef CONFIG_SMP
-        set_irq_affinity_info((vector & 0xff), sn_irq_info->irq_cpuid, 0);
+        set_irq_affinity_info(irq, sn_irq_info->irq_cpuid, 0);
 #endif
 
         return 0;
 }
 
 static void
-sn_msi_target(unsigned int vector, unsigned int cpu,
-              u32 *addr_hi, u32 *addr_lo)
+sn_msi_target(unsigned int irq, cpumask_t cpu_mask, struct msi_msg *msg)
 {
         int slice;
         nasid_t nasid;
@@ -150,8 +148,10 @@ sn_msi_target(unsigned int vector, unsigned int cpu,
         struct sn_irq_info *sn_irq_info;
         struct sn_irq_info *new_irq_info;
         struct sn_pcibus_provider *provider;
+        unsigned int cpu;
 
-        sn_irq_info = sn_msi_info[vector].sn_irq_info;
+        cpu = first_cpu(cpu_mask);
+        sn_irq_info = sn_msi_info[irq].sn_irq_info;
         if (sn_irq_info == NULL || sn_irq_info->irq_int_bit >= 0)
                 return;
 
@@ -163,15 +163,15 @@ sn_msi_target(unsigned int vector, unsigned int cpu,
         pdev = sn_pdev->pdi_linux_pcidev;
         provider = SN_PCIDEV_BUSPROVIDER(pdev);
 
-        bus_addr = (u64)(*addr_hi) << 32 | (u64)(*addr_lo);
+        bus_addr = (u64)(msg->address_hi) << 32 | (u64)(msg->address_lo);
         (*provider->dma_unmap)(pdev, bus_addr, PCI_DMA_FROMDEVICE);
-        sn_msi_info[vector].pci_addr = 0;
+        sn_msi_info[irq].pci_addr = 0;
 
         nasid = cpuid_to_nasid(cpu);
         slice = cpuid_to_slice(cpu);
 
         new_irq_info = sn_retarget_vector(sn_irq_info, nasid, slice);
-        sn_msi_info[vector].sn_irq_info = new_irq_info;
+        sn_msi_info[irq].sn_irq_info = new_irq_info;
         if (new_irq_info == NULL)
                 return;
 
@@ -184,12 +184,13 @@ sn_msi_target(unsigned int vector, unsigned int cpu,
                                         sizeof(new_irq_info->irq_xtalkaddr),
                                         SN_DMA_MSI|SN_DMA_ADDR_XIO);
 
-        sn_msi_info[vector].pci_addr = bus_addr;
-        *addr_hi = (u32)(bus_addr >> 32);
-        *addr_lo = (u32)(bus_addr & 0x00000000ffffffff);
+        sn_msi_info[irq].pci_addr = bus_addr;
+        msg->address_hi = (u32)(bus_addr >> 32);
+        msg->address_lo = (u32)(bus_addr & 0x00000000ffffffff);
 }
 
 struct msi_ops sn_msi_ops = {
+        .needs_64bit_address = 1,
         .setup = sn_msi_setup,
         .teardown = sn_msi_teardown,
 #ifdef CONFIG_SMP
@@ -201,7 +202,7 @@ int
 sn_msi_init(void)
 {
         sn_msi_info =
-                kzalloc(sizeof(struct sn_msi_info) * NR_VECTORS, GFP_KERNEL);
+                kzalloc(sizeof(struct sn_msi_info) * NR_IRQS, GFP_KERNEL);
         if (! sn_msi_info)
                 return -ENOMEM;
 
diff --git a/drivers/pci/msi-apic.c b/drivers/pci/msi-apic.c
index 5ed798b319c7..afc0ed13aa89 100644
--- a/drivers/pci/msi-apic.c
+++ b/drivers/pci/msi-apic.c
@@ -46,37 +46,36 @@
 
 
 static void
-msi_target_apic(unsigned int vector,
-                unsigned int dest_cpu,
-                u32 *address_hi,        /* in/out */
-                u32 *address_lo)        /* in/out */
+msi_target_apic(unsigned int irq, cpumask_t cpu_mask, struct msi_msg *msg)
 {
-        u32 addr = *address_lo;
+        u32 addr = msg->address_lo;
 
         addr &= MSI_ADDR_DESTID_MASK;
-        addr |= MSI_ADDR_DESTID_CPU(cpu_physical_id(dest_cpu));
+        addr |= MSI_ADDR_DESTID_CPU(cpu_physical_id(first_cpu(cpu_mask)));
 
-        *address_lo = addr;
+        msg->address_lo = addr;
 }
 
 static int
 msi_setup_apic(struct pci_dev *pdev,    /* unused in generic */
-                unsigned int vector,
-                u32 *address_hi,
-                u32 *address_lo,
-                u32 *data)
+                unsigned int irq,
+                struct msi_msg *msg)
 {
         unsigned long   dest_phys_id;
+        unsigned int    vector;
 
         dest_phys_id = cpu_physical_id(first_cpu(cpu_online_map));
+        vector = irq;
 
-        *address_hi = 0;
-        *address_lo =   MSI_ADDR_HEADER |
-                        MSI_ADDR_DESTMODE_PHYS |
-                        MSI_ADDR_REDIRECTION_CPU |
-                        MSI_ADDR_DESTID_CPU(dest_phys_id);
+        msg->address_hi = 0;
+        msg->address_lo =
+                MSI_ADDR_HEADER |
+                MSI_ADDR_DESTMODE_PHYS |
+                MSI_ADDR_REDIRECTION_CPU |
+                MSI_ADDR_DESTID_CPU(dest_phys_id);
 
-        *data = MSI_DATA_TRIGGER_EDGE |
+        msg->data =
+                MSI_DATA_TRIGGER_EDGE |
                 MSI_DATA_LEVEL_ASSERT |
                 MSI_DATA_DELIVERY_FIXED |
                 MSI_DATA_VECTOR(vector);
@@ -85,7 +84,7 @@ msi_setup_apic(struct pci_dev *pdev,	/* unused in generic */
 }
 
 static void
-msi_teardown_apic(unsigned int vector)
+msi_teardown_apic(unsigned int irq)
 {
         return;         /* no-op */
 }
@@ -95,6 +94,7 @@ msi_teardown_apic(unsigned int vector)
  */
 
 struct msi_ops msi_apic_ops = {
+        .needs_64bit_address = 0,
         .setup = msi_setup_apic,
         .teardown = msi_teardown_apic,
         .target = msi_target_apic,
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index cca6cb3ccdac..6d9de026e141 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -165,19 +165,17 @@ static void write_msi_msg(struct msi_desc *entry, struct msi_msg *msg)
 }
 
 #ifdef CONFIG_SMP
-static void set_msi_affinity(unsigned int vector, cpumask_t cpu_mask)
+static void set_msi_affinity(unsigned int irq, cpumask_t cpu_mask)
 {
         struct msi_desc *entry;
         struct msi_msg msg;
-        unsigned int irq = vector;
-        unsigned int dest_cpu = first_cpu(cpu_mask);
 
-        entry = (struct msi_desc *)msi_desc[vector];
+        entry = msi_desc[irq];
         if (!entry || !entry->dev)
                 return;
 
         read_msi_msg(entry, &msg);
-        msi_ops->target(vector, dest_cpu, &msg.address_hi, &msg.address_lo);
+        msi_ops->target(irq, cpu_mask, &msg);
         write_msi_msg(entry, &msg);
         set_native_irq_info(irq, cpu_mask);
 }
@@ -701,14 +699,14 @@ static int msi_register_init(struct pci_dev *dev, struct msi_desc *entry)
 {
         int status;
         struct msi_msg msg;
-        int pos, vector = dev->irq;
+        int pos;
         u16 control;
 
         pos = entry->msi_attrib.pos;
         pci_read_config_word(dev, msi_control_reg(pos), &control);
 
         /* Configure MSI capability structure */
-        status = msi_ops->setup(dev, vector, &msg.address_hi, &msg.address_lo, &msg.data);
+        status = msi_ops->setup(dev, dev->irq, &msg);
         if (status < 0)
                 return status;
 
@@ -863,10 +861,7 @@ static int msix_capability_init(struct pci_dev *dev,
                 /* Replace with MSI-X handler */
                 irq_handler_init(PCI_CAP_ID_MSIX, vector, 1);
                 /* Configure MSI-X capability structure */
-                status = msi_ops->setup(dev, vector,
-                                        &msg.address_hi,
-                                        &msg.address_lo,
-                                        &msg.data);
+                status = msi_ops->setup(dev, vector, &msg);
                 if (status < 0)
                         break;
 
@@ -928,6 +923,7 @@ int pci_msi_supported(struct pci_dev * dev)
 int pci_enable_msi(struct pci_dev* dev)
 {
         int pos, temp, status;
+        u16 control;
 
         if (pci_msi_supported(dev) < 0)
                 return -EINVAL;
@@ -942,6 +938,10 @@ int pci_enable_msi(struct pci_dev* dev)
         if (!pos)
                 return -EINVAL;
 
+        pci_read_config_word(dev, msi_control_reg(pos), &control);
+        if (!is_64bit_address(control) && msi_ops->needs_64bit_address)
+                return -EINVAL;
+
         WARN_ON(!msi_lookup_vector(dev, PCI_CAP_ID_MSI));
 
         /* Check whether driver already requested for MSI-X vectors */
diff --git a/drivers/pci/msi.h b/drivers/pci/msi.h
index 62f61b61d2c9..3519eca50d8a 100644
--- a/drivers/pci/msi.h
+++ b/drivers/pci/msi.h
@@ -6,68 +6,6 @@
 #ifndef MSI_H
 #define MSI_H
 
-/*
- * MSI operation vector.  Used by the msi core code (drivers/pci/msi.c)
- * to abstract platform-specific tasks relating to MSI address generation
- * and resource management.
- */
-struct msi_ops {
-        /**
-         * setup - generate an MSI bus address and data for a given vector
-         * @pdev: PCI device context (in)
-         * @vector: vector allocated by the msi core (in)
-         * @addr_hi: upper 32 bits of PCI bus MSI address (out)
-         * @addr_lo: lower 32 bits of PCI bus MSI address (out)
-         * @data: MSI data payload (out)
-         *
-         * Description: The setup op is used to generate a PCI bus addres and
-         * data which the msi core will program into the card MSI capability
-         * registers.  The setup routine is responsible for picking an initial
-         * cpu to target the MSI at.  The setup routine is responsible for
-         * examining pdev to determine the MSI capabilities of the card and
-         * generating a suitable address/data.  The setup routine is
-         * responsible for allocating and tracking any system resources it
-         * needs to route the MSI to the cpu it picks, and for associating
-         * those resources with the passed in vector.
-         *
-         * Returns 0 if the MSI address/data was successfully setup.
-         **/
-
-        int     (*setup)    (struct pci_dev *pdev, unsigned int vector,
-                             u32 *addr_hi, u32 *addr_lo, u32 *data);
-
-        /**
-         * teardown - release resources allocated by setup
-         * @vector: vector context for resources (in)
-         *
-         * Description:  The teardown op is used to release any resources
-         * that were allocated in the setup routine associated with the passed
-         * in vector.
-         **/
-
-        void    (*teardown) (unsigned int vector);
-
-        /**
-         * target - retarget an MSI at a different cpu
-         * @vector: vector context for resources (in)
-         * @cpu:  new cpu to direct vector at (in)
-         * @addr_hi: new value of PCI bus upper 32 bits (in/out)
-         * @addr_lo: new value of PCI bus lower 32 bits (in/out)
-         *
-         * Description:  The target op is used to redirect an MSI vector
-         * at a different cpu.  addr_hi/addr_lo coming in are the existing
-         * values that the MSI core has programmed into the card.  The
-         * target code is responsible for freeing any resources (if any)
-         * associated with the old address, and generating a new PCI bus
-         * addr_hi/addr_lo that will redirect the vector at the indicated cpu.
-         **/
-
-        void    (*target)   (unsigned int vector, unsigned int cpu,
-                             u32 *addr_hi, u32 *addr_lo);
-};
-
-extern int msi_register(struct msi_ops *ops);
-
 #include <asm/msi.h>
 
 /*
diff --git a/include/linux/pci.h b/include/linux/pci.h
index b9bb6c46e056..2aabe90f1cd2 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -617,6 +617,68 @@ extern int pci_enable_msix(struct pci_dev* dev,
         struct msix_entry *entries, int nvec);
 extern void pci_disable_msix(struct pci_dev *dev);
 extern void msi_remove_pci_irq_vectors(struct pci_dev *dev);
+
+/*
+ * MSI operation vector.  Used by the msi core code (drivers/pci/msi.c)
+ * to abstract platform-specific tasks relating to MSI address generation
+ * and resource management.
+ */
+struct msi_ops {
+        int needs_64bit_address;
+        /**
+         * setup - generate an MSI bus address and data for a given vector
+         * @pdev: PCI device context (in)
+         * @irq: irq allocated by the msi core (in)
+         * @msg: PCI bus address and data for msi message (out)
+         *
+         * Description: The setup op is used to generate a PCI bus addres and
+         * data which the msi core will program into the card MSI capability
+         * registers.  The setup routine is responsible for picking an initial
+         * cpu to target the MSI at.  The setup routine is responsible for
+         * examining pdev to determine the MSI capabilities of the card and
+         * generating a suitable address/data.  The setup routine is
+         * responsible for allocating and tracking any system resources it
+         * needs to route the MSI to the cpu it picks, and for associating
+         * those resources with the passed in vector.
+         *
+         * Returns 0 if the MSI address/data was successfully setup.
+         **/
+
+        int     (*setup)    (struct pci_dev *pdev, unsigned int irq,
+                             struct msi_msg *msg);
+
+        /**
+         * teardown - release resources allocated by setup
+         * @vector: vector context for resources (in)
+         *
+         * Description:  The teardown op is used to release any resources
+         * that were allocated in the setup routine associated with the passed
+         * in vector.
+         **/
+
+        void    (*teardown) (unsigned int irq);
+
+        /**
+         * target - retarget an MSI at a different cpu
+         * @vector: vector context for resources (in)
+         * @cpu:  new cpu to direct vector at (in)
+         * @addr_hi: new value of PCI bus upper 32 bits (in/out)
+         * @addr_lo: new value of PCI bus lower 32 bits (in/out)
+         *
+         * Description:  The target op is used to redirect an MSI vector
+         * at a different cpu.  addr_hi/addr_lo coming in are the existing
+         * values that the MSI core has programmed into the card.  The
+         * target code is responsible for freeing any resources (if any)
+         * associated with the old address, and generating a new PCI bus
+         * addr_hi/addr_lo that will redirect the vector at the indicated cpu.
+         **/
+
+        void    (*target)   (unsigned int irq, cpumask_t cpumask,
+                             struct msi_msg *msg);
+};
+
+extern int msi_register(struct msi_ops *ops);
+
 #endif
 
 extern void pci_block_user_cfg_access(struct pci_dev *dev);