3 files changed, 32 insertions, 15 deletions

diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index 98336200c7b2..598f023cf8a6 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -190,6 +190,11 @@ int zpci_fmb_enable_device(struct zpci_dev *zdev)
 		return -ENOMEM;
 	WARN_ON((u64) zdev->fmb & 0xf);
 
+	/* reset software counters */
+	atomic64_set(&zdev->allocated_pages, 0);
+	atomic64_set(&zdev->mapped_pages, 0);
+	atomic64_set(&zdev->unmapped_pages, 0);
+
 	args.fmb_addr = virt_to_phys(zdev->fmb);
 	return mod_pci(zdev, ZPCI_MOD_FC_SET_MEASURE, 0, &args);
 }
@@ -822,6 +827,7 @@ int zpci_create_device(struct zpci_dev *zdev)
 	if (rc)
 		goto out;
 
+	mutex_init(&zdev->lock);
 	if (zdev->state == ZPCI_FN_STATE_CONFIGURED) {
 		rc = zpci_enable_device(zdev);
 		if (rc)
diff --git a/arch/s390/pci/pci_debug.c b/arch/s390/pci/pci_debug.c
index c22d4402ae45..4129b0a5fd78 100644
--- a/arch/s390/pci/pci_debug.c
+++ b/arch/s390/pci/pci_debug.c
@@ -31,12 +31,25 @@ static char *pci_perf_names[] = {
 	"Refresh operations",
 	"DMA read bytes",
 	"DMA write bytes",
-	/* software counters */
+};
+
+static char *pci_sw_names[] = {
 	"Allocated pages",
 	"Mapped pages",
 	"Unmapped pages",
 };
 
+static void pci_sw_counter_show(struct seq_file *m)
+{
+	struct zpci_dev *zdev = m->private;
+	atomic64_t *counter = &zdev->allocated_pages;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(pci_sw_names); i++, counter++)
+		seq_printf(m, "%26s:\t%llu\n", pci_sw_names[i],
+			   atomic64_read(counter));
+}
+
 static int pci_perf_show(struct seq_file *m, void *v)
 {
 	struct zpci_dev *zdev = m->private;
@@ -45,7 +58,10 @@ static int pci_perf_show(struct seq_file *m, void *v)
 
 	if (!zdev)
 		return 0;
+
+	mutex_lock(&zdev->lock);
 	if (!zdev->fmb) {
+		mutex_unlock(&zdev->lock);
 		seq_puts(m, "FMB statistics disabled\n");
 		return 0;
 	}
@@ -65,12 +81,9 @@ static int pci_perf_show(struct seq_file *m, void *v)
 		for (i = 4; i < 6; i++)
 			seq_printf(m, "%26s:\t%llu\n",
 				   pci_perf_names[i], *(stat + i));
-	/* software counters */
-	for (i = 6; i < ARRAY_SIZE(pci_perf_names); i++)
-		seq_printf(m, "%26s:\t%llu\n",
-			   pci_perf_names[i],
-			   atomic64_read((atomic64_t *) (stat + i)));
 
+	pci_sw_counter_show(m);
+	mutex_unlock(&zdev->lock);
 	return 0;
 }
 
@@ -88,19 +101,17 @@ static ssize_t pci_perf_seq_write(struct file *file, const char __user *ubuf,
 	if (rc)
 		return rc;
 
+	mutex_lock(&zdev->lock);
 	switch (val) {
 	case 0:
 		rc = zpci_fmb_disable_device(zdev);
-		if (rc)
-			return rc;
 		break;
 	case 1:
 		rc = zpci_fmb_enable_device(zdev);
-		if (rc)
-			return rc;
 		break;
 	}
-	return count;
+	mutex_unlock(&zdev->lock);
+	return rc ? rc : count;
 }
 
 static int pci_perf_seq_open(struct inode *inode, struct file *filp)
diff --git a/arch/s390/pci/pci_dma.c b/arch/s390/pci/pci_dma.c
index 4cbb29a4d615..6fd8d5836138 100644
--- a/arch/s390/pci/pci_dma.c
+++ b/arch/s390/pci/pci_dma.c
@@ -300,7 +300,7 @@ static dma_addr_t s390_dma_map_pages(struct device *dev, struct page *page,
 		flags |= ZPCI_TABLE_PROTECTED;
 
 	if (!dma_update_trans(zdev, pa, dma_addr, size, flags)) {
-		atomic64_add(nr_pages, &zdev->fmb->mapped_pages);
+		atomic64_add(nr_pages, &zdev->mapped_pages);
 		return dma_addr + (offset & ~PAGE_MASK);
 	}
 
@@ -328,7 +328,7 @@ static void s390_dma_unmap_pages(struct device *dev, dma_addr_t dma_addr,
 		zpci_err_hex(&dma_addr, sizeof(dma_addr));
 	}
 
-	atomic64_add(npages, &zdev->fmb->unmapped_pages);
+	atomic64_add(npages, &zdev->unmapped_pages);
 	iommu_page_index = (dma_addr - zdev->start_dma) >> PAGE_SHIFT;
 	dma_free_iommu(zdev, iommu_page_index, npages);
 }
@@ -357,7 +357,7 @@ static void *s390_dma_alloc(struct device *dev, size_t size,
 		return NULL;
 	}
 
-	atomic64_add(size / PAGE_SIZE, &zdev->fmb->allocated_pages);
+	atomic64_add(size / PAGE_SIZE, &zdev->allocated_pages);
 	if (dma_handle)
 		*dma_handle = map;
 	return (void *) pa;
@@ -370,7 +370,7 @@ static void s390_dma_free(struct device *dev, size_t size,
 	struct zpci_dev *zdev = get_zdev(to_pci_dev(dev));
 
 	size = PAGE_ALIGN(size);
-	atomic64_sub(size / PAGE_SIZE, &zdev->fmb->allocated_pages);
+	atomic64_sub(size / PAGE_SIZE, &zdev->allocated_pages);
 	s390_dma_unmap_pages(dev, dma_handle, size, DMA_BIDIRECTIONAL, NULL);
 	free_pages((unsigned long) pa, get_order(size));
 }