sparc64: Fix build errors with gcc-4.6.0

Most of the warnings emitted (we fail arch/sparc file
builds with -Werror) were legitimate but harmless, however
one case (n2_pcr_write) was a genuine bug.

Based almost entirely upon a patch by Sam Ravnborg.
Reported-by: Dennis Gilmore <dennis@ausil.us>
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc/kernel/iommu.c

@@ -333,13 +333,10 @@ static void dma_4u_free_coherent(struct device *dev, size_t size,
 				 void *cpu, dma_addr_t dvma)
 {
 	struct iommu *iommu;
-	iopte_t *iopte;
 	unsigned long flags, order, npages;
 
 	npages = IO_PAGE_ALIGN(size) >> IO_PAGE_SHIFT;
 	iommu = dev->archdata.iommu;
-	iopte = iommu->page_table +
-		((dvma - iommu->page_table_map_base) >> IO_PAGE_SHIFT);
 
 	spin_lock_irqsave(&iommu->lock, flags);
 

arch/sparc/kernel/ldc.c

@@ -790,13 +790,17 @@ static void send_events(struct ldc_channel *lp, unsigned int event_mask)
 static irqreturn_t ldc_rx(int irq, void *dev_id)
 {
 	struct ldc_channel *lp = dev_id;
-	unsigned long orig_state, hv_err, flags;
+	unsigned long orig_state, flags;
 	unsigned int event_mask;
 
 	spin_lock_irqsave(&lp->lock, flags);
 
 	orig_state = lp->chan_state;
-	hv_err = sun4v_ldc_rx_get_state(lp->id,
+
+	/* We should probably check for hypervisor errors here and
+	 * reset the LDC channel if we get one.
+	 */
+	sun4v_ldc_rx_get_state(lp->id,
 			       &lp->rx_head,
 			       &lp->rx_tail,
 			       &lp->chan_state);
@@ -904,13 +908,17 @@ static irqreturn_t ldc_rx(int irq, void *dev_id)
 static irqreturn_t ldc_tx(int irq, void *dev_id)
 {
 	struct ldc_channel *lp = dev_id;
-	unsigned long flags, hv_err, orig_state;
+	unsigned long flags, orig_state;
 	unsigned int event_mask = 0;
 
 	spin_lock_irqsave(&lp->lock, flags);
 
 	orig_state = lp->chan_state;
-	hv_err = sun4v_ldc_tx_get_state(lp->id,
+
+	/* We should probably check for hypervisor errors here and
+	 * reset the LDC channel if we get one.
+	 */
+	sun4v_ldc_tx_get_state(lp->id,
 			       &lp->tx_head,
 			       &lp->tx_tail,
 			       &lp->chan_state);

arch/sparc/kernel/pci.c

@@ -675,6 +675,7 @@ static void __devinit pci_bus_register_of_sysfs(struct pci_bus *bus)
 		 * humanoid.
 		 */
 		err = sysfs_create_file(&dev->dev.kobj, &dev_attr_obppath.attr);
+		(void) err;
 	}
 	list_for_each_entry(child_bus, &bus->children, node)
 		pci_bus_register_of_sysfs(child_bus);

arch/sparc/kernel/pci_common.c

@@ -295,12 +295,15 @@ static int sun4v_write_pci_cfg(struct pci_bus *bus_dev, unsigned int devfn,
 	unsigned int bus = bus_dev->number;
 	unsigned int device = PCI_SLOT(devfn);
 	unsigned int func = PCI_FUNC(devfn);
-	unsigned long ret;
 
 	if (config_out_of_range(pbm, bus, devfn, where)) {
 		/* Do nothing. */
 	} else {
-		ret = pci_sun4v_config_put(devhandle,
+		/* We don't check for hypervisor errors here, but perhaps
+		 * we should and influence our return value depending upon
+		 * what kind of error is thrown.
+		 */
+		pci_sun4v_config_put(devhandle,
 				     HV_PCI_DEVICE_BUILD(bus, device, func),
 				     where, size, value);
 	}

arch/sparc/kernel/pci_fire.c

@@ -214,11 +214,9 @@ static int pci_fire_msi_setup(struct pci_pbm_info *pbm, unsigned long msiqid,
 
 static int pci_fire_msi_teardown(struct pci_pbm_info *pbm, unsigned long msi)
 {
-	unsigned long msiqid;
 	u64 val;
 
 	val = upa_readq(pbm->pbm_regs + MSI_MAP(msi));
-	msiqid = (val & MSI_MAP_EQNUM);
 
 	val &= ~MSI_MAP_VALID;
 

arch/sparc/kernel/pci_schizo.c

@@ -1313,7 +1313,7 @@ static int __devinit schizo_pbm_init(struct pci_pbm_info *pbm,
 	const struct linux_prom64_registers *regs;
 	struct device_node *dp = op->dev.of_node;
 	const char *chipset_name;
-	int is_pbm_a, err;
+	int err;
 
 	switch (chip_type) {
 	case PBM_CHIP_TYPE_TOMATILLO:
@@ -1343,8 +1343,6 @@ static int __devinit schizo_pbm_init(struct pci_pbm_info *pbm,
 	 */
 	regs = of_get_property(dp, "reg", NULL);
 
-	is_pbm_a = ((regs[0].phys_addr & 0x00700000) == 0x00600000);
-
 	pbm->next = pci_pbm_root;
 	pci_pbm_root = pbm;
 

arch/sparc/kernel/pci_sun4v.c

@@ -580,7 +580,7 @@ static int __devinit pci_sun4v_iommu_init(struct pci_pbm_info *pbm)
 {
 	static const u32 vdma_default[] = { 0x80000000, 0x80000000 };
 	struct iommu *iommu = pbm->iommu;
-	unsigned long num_tsb_entries, sz, tsbsize;
+	unsigned long num_tsb_entries, sz;
 	u32 dma_mask, dma_offset;
 	const u32 *vdma;
 
@@ -596,7 +596,6 @@ static int __devinit pci_sun4v_iommu_init(struct pci_pbm_info *pbm)
 
 	dma_mask = (roundup_pow_of_two(vdma[1]) - 1UL);
 	num_tsb_entries = vdma[1] / IO_PAGE_SIZE;
-	tsbsize = num_tsb_entries * sizeof(iopte_t);
 
 	dma_offset = vdma[0];
 

arch/sparc/kernel/pcr.c

@@ -81,7 +81,7 @@ static void n2_pcr_write(u64 val)
 	unsigned long ret;
 
 	ret = sun4v_niagara2_setperf(HV_N2_PERF_SPARC_CTL, val);
-	if (val != HV_EOK)
+	if (ret != HV_EOK)
 		write_pcr(val);
 }
 

arch/sparc/kernel/ptrace_64.c

@@ -1086,6 +1086,7 @@ asmlinkage int syscall_trace_enter(struct pt_regs *regs)
 
 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
 {
+#ifdef CONFIG_AUDITSYSCALL
 	if (unlikely(current->audit_context)) {
 		unsigned long tstate = regs->tstate;
 		int result = AUDITSC_SUCCESS;
@@ -1095,7 +1096,7 @@ asmlinkage void syscall_trace_leave(struct pt_regs *regs)
 
 		audit_syscall_exit(result, regs->u_regs[UREG_I0]);
 	}
-
+#endif
 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 		trace_sys_exit(regs, regs->u_regs[UREG_G1]);
 

arch/sparc/kernel/smp_64.c

@@ -189,7 +189,7 @@ static inline long get_delta (long *rt, long *master)
 void smp_synchronize_tick_client(void)
 {
 	long i, delta, adj, adjust_latency = 0, done = 0;
-	unsigned long flags, rt, master_time_stamp, bound;
+	unsigned long flags, rt, master_time_stamp;
 #if DEBUG_TICK_SYNC
 	struct {
 		long rt;	/* roundtrip time */
@@ -208,10 +208,8 @@ void smp_synchronize_tick_client(void)
 	{
 		for (i = 0; i < NUM_ROUNDS; i++) {
 			delta = get_delta(&rt, &master_time_stamp);
-			if (delta == 0) {
+			if (delta == 0)
 				done = 1;	/* let's lock on to this... */
-				bound = rt;
-			}
 
 			if (!done) {
 				if (i > 0) {
@@ -933,13 +931,12 @@ void smp_flush_dcache_page_impl(struct page *page, int cpu)
 void flush_dcache_page_all(struct mm_struct *mm, struct page *page)
 {
 	void *pg_addr;
-	int this_cpu;
 	u64 data0;
 
 	if (tlb_type == hypervisor)
 		return;
 
-	this_cpu = get_cpu();
+	preempt_disable();
 
 #ifdef CONFIG_DEBUG_DCFLUSH
 	atomic_inc(&dcpage_flushes);
@@ -964,7 +961,7 @@ void flush_dcache_page_all(struct mm_struct *mm, struct page *page)
 	}
 	__local_flush_dcache_page(page);
 
-	put_cpu();
+	preempt_enable();
 }
 
 void __irq_entry smp_new_mmu_context_version_client(int irq, struct pt_regs *regs)

arch/sparc/kernel/traps_64.c

@@ -2152,7 +2152,7 @@ static void user_instruction_dump(unsigned int __user *pc)
 
 void show_stack(struct task_struct *tsk, unsigned long *_ksp)
 {
-	unsigned long fp, thread_base, ksp;
+	unsigned long fp, ksp;
 	struct thread_info *tp;
 	int count = 0;
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
@@ -2173,7 +2173,6 @@ void show_stack(struct task_struct *tsk, unsigned long *_ksp)
 		flushw_all();
 
 	fp = ksp + STACK_BIAS;
-	thread_base = (unsigned long) tp;
 
 	printk("Call Trace:\n");
 	do {