[SPARC64]: Fix several bugs in MSI handling.

1) sun4{u,v}_build_msi() have improper return value handling.

   We should always return negative error codes, instead of
   using the magic value "0" which could in fact be a valid
   MSI number.

2) sun4{u,v}_build_msi() should return -ENOMEM instead of
   calling prom_prom() halt with kzalloc() of the interrupt
   data fails.

3) We 'remembered' the MSI number using a singleton in the
   struct device archdata area, this doesn't work for MSI-X
   which can cause multiple MSIs assosciated with one device.

   Delete that archdata member, and instead store the MSI
   number in the IRQ chip data area.
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc64/kernel/irq.c

@@ -217,8 +217,27 @@ struct irq_handler_data {
 	void		(*pre_handler)(unsigned int, void *, void *);
 	void		*pre_handler_arg1;
 	void		*pre_handler_arg2;
+
+	u32		msi;
 };
 
+void sparc64_set_msi(unsigned int virt_irq, u32 msi)
+{
+	struct irq_handler_data *data = get_irq_chip_data(virt_irq);
+
+	if (data)
+		data->msi = msi;
+}
+
+u32 sparc64_get_msi(unsigned int virt_irq)
+{
+	struct irq_handler_data *data = get_irq_chip_data(virt_irq);
+
+	if (data)
+		return data->msi;
+	return 0xffffffff;
+}
+
 static inline struct ino_bucket *virt_irq_to_bucket(unsigned int virt_irq)
 {
 	unsigned int real_irq = virt_to_real_irq(virt_irq);
@@ -741,7 +760,7 @@ unsigned int sun4v_build_msi(u32 devhandle, unsigned int *virt_irq_p,
 			break;
 	}
 	if (devino >= msi_end)
-		return 0;
+		return -ENOSPC;
 
 	sysino = sun4v_devino_to_sysino(devhandle, devino);
 	bucket = &ivector_table[sysino];
@@ -755,8 +774,8 @@ unsigned int sun4v_build_msi(u32 devhandle, unsigned int *virt_irq_p,
 
 	data = kzalloc(sizeof(struct irq_handler_data), GFP_ATOMIC);
 	if (unlikely(!data)) {
-		prom_printf("IRQ: kzalloc(irq_handler_data) failed.\n");
-		prom_halt();
+		virt_irq_free(*virt_irq_p);
+		return -ENOMEM;
 	}
 	set_irq_chip_data(bucket->virt_irq, data);
 

arch/sparc64/kernel/pci.c

@@ -393,7 +393,6 @@ struct pci_dev *of_create_pci_dev(struct pci_pbm_info *pbm,
 	sd->host_controller = pbm;
 	sd->prom_node = node;
 	sd->op = of_find_device_by_node(node);
-	sd->msi_num = 0xffffffff;
 
 	sd = &sd->op->dev.archdata;
 	sd->iommu = pbm->iommu;

arch/sparc64/kernel/pci_sun4v.c

@@ -940,13 +940,13 @@ static int pci_sun4v_setup_msi_irq(unsigned int *virt_irq_p,
 	if (msi_num < 0)
 		return msi_num;
 
-	devino = sun4v_build_msi(pbm->devhandle, virt_irq_p,
-				 pbm->msiq_first_devino,
-				 (pbm->msiq_first_devino +
-				  pbm->msiq_num));
-	err = -ENOMEM;
-	if (!devino)
+	err = sun4v_build_msi(pbm->devhandle, virt_irq_p,
+			      pbm->msiq_first_devino,
+			      (pbm->msiq_first_devino +
+			       pbm->msiq_num));
+	if (err < 0)
 		goto out_err;
+	devino = err;
 
 	msiqid = ((devino - pbm->msiq_first_devino) +
 		  pbm->msiq_first);
@@ -971,7 +971,7 @@ static int pci_sun4v_setup_msi_irq(unsigned int *virt_irq_p,
 	if (pci_sun4v_msi_setvalid(pbm->devhandle, msi_num, HV_MSIVALID_VALID))
 		goto out_err;
 
-	pdev->dev.archdata.msi_num = msi_num;
+	sparc64_set_msi(*virt_irq_p, msi_num);
 
 	if (entry->msi_attrib.is_64) {
 		msg.address_hi = pbm->msi64_start >> 32;
@@ -993,8 +993,6 @@ static int pci_sun4v_setup_msi_irq(unsigned int *virt_irq_p,
 
 out_err:
 	free_msi(pbm, msi_num);
-	sun4v_destroy_msi(*virt_irq_p);
-	*virt_irq_p = 0;
 	return err;
 
 }
@@ -1006,7 +1004,7 @@ static void pci_sun4v_teardown_msi_irq(unsigned int virt_irq,
 	unsigned long msiqid, err;
 	unsigned int msi_num;
 
-	msi_num = pdev->dev.archdata.msi_num;
+	msi_num = sparc64_get_msi(virt_irq);
 	err = pci_sun4v_msi_getmsiq(pbm->devhandle, msi_num, &msiqid);
 	if (err) {
 		printk(KERN_ERR "%s: getmsiq gives error %lu\n",

include/asm-sparc64/device.h

@@ -16,8 +16,6 @@ struct dev_archdata {
 
 	struct device_node	*prom_node;
 	struct of_device	*op;
-
-	unsigned int		msi_num;
 };
 
 #endif /* _ASM_SPARC64_DEVICE_H */

include/asm-sparc64/irq.h

@@ -53,6 +53,9 @@ extern unsigned int sun4v_build_msi(u32 devhandle, unsigned int *virt_irq_p,
 extern void sun4v_destroy_msi(unsigned int virt_irq);
 extern unsigned int sbus_build_irq(void *sbus, unsigned int ino);
 
+extern void sparc64_set_msi(unsigned int virt_irq, u32 msi);
+extern u32 sparc64_get_msi(unsigned int virt_irq);
+
 extern void fixup_irqs(void);
 
 static __inline__ void set_softint(unsigned long bits)