6 files changed, 46 insertions, 24 deletions

diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index 30de42730b2f..2fa7b14b9c08 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -15,8 +15,8 @@
  *   Thomas Klein
  */
 
-#define COMPONENT "zPCI"
-#define pr_fmt(fmt) COMPONENT ": " fmt
+#define KMSG_COMPONENT "zpci"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
 #include <linux/kernel.h>
 #include <linux/slab.h>
diff --git a/arch/s390/pci/pci_clp.c b/arch/s390/pci/pci_clp.c
index 96545d7659fd..6e22a247de9b 100644
--- a/arch/s390/pci/pci_clp.c
+++ b/arch/s390/pci/pci_clp.c
@@ -5,8 +5,8 @@
  *   Jan Glauber <jang@linux.vnet.ibm.com>
  */
 
-#define COMPONENT "zPCI"
-#define pr_fmt(fmt) COMPONENT ": " fmt
+#define KMSG_COMPONENT "zpci"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
 #include <linux/kernel.h>
 #include <linux/slab.h>
diff --git a/arch/s390/pci/pci_debug.c b/arch/s390/pci/pci_debug.c
index c5c66840ac00..eec598c5939f 100644
--- a/arch/s390/pci/pci_debug.c
+++ b/arch/s390/pci/pci_debug.c
@@ -5,8 +5,8 @@
  *    Jan Glauber <jang@linux.vnet.ibm.com>
  */
 
-#define COMPONENT "zPCI"
-#define pr_fmt(fmt) COMPONENT ": " fmt
+#define KMSG_COMPONENT "zpci"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
 #include <linux/kernel.h>
 #include <linux/seq_file.h>
diff --git a/arch/s390/pci/pci_dma.c b/arch/s390/pci/pci_dma.c
index f91c03119804..4cbb29a4d615 100644
--- a/arch/s390/pci/pci_dma.c
+++ b/arch/s390/pci/pci_dma.c
@@ -16,6 +16,13 @@
 
 static struct kmem_cache *dma_region_table_cache;
 static struct kmem_cache *dma_page_table_cache;
+static int s390_iommu_strict;
+
+static int zpci_refresh_global(struct zpci_dev *zdev)
+{
+        return zpci_refresh_trans((u64) zdev->fh << 32, zdev->start_dma,
+                                  zdev->iommu_pages * PAGE_SIZE);
+}
 
 static unsigned long *dma_alloc_cpu_table(void)
 {
@@ -155,18 +162,15 @@ static int dma_update_trans(struct zpci_dev *zdev, unsigned long pa,
         }
 
         /*
-         * rpcit is not required to establish new translations when previously
-         * invalid translation-table entries are validated, however it is
-         * required when altering previously valid entries.
+         * With zdev->tlb_refresh == 0, rpcit is not required to establish new
+         * translations when previously invalid translation-table entries are
+         * validated. With lazy unmap, it also is skipped for previously valid
+         * entries, but a global rpcit is then required before any address can
+         * be re-used, i.e. after each iommu bitmap wrap-around.
          */
         if (!zdev->tlb_refresh &&
-            ((flags & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID))
-                /*
-                 * TODO: also need to check that the old entry is indeed INVALID
-                 * and not only for one page but for the whole range...
-                 * -> now we WARN_ON in that case but with lazy unmap that
-                 * needs to be redone!
-                 */
+                        (!s390_iommu_strict ||
+                        ((flags & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID)))
                 goto no_refresh;
 
         rc = zpci_refresh_trans((u64) zdev->fh << 32, start_dma_addr,
@@ -220,16 +224,21 @@ static unsigned long __dma_alloc_iommu(struct zpci_dev *zdev,
 static unsigned long dma_alloc_iommu(struct zpci_dev *zdev, int size)
 {
         unsigned long offset, flags;
+        int wrap = 0;
 
         spin_lock_irqsave(&zdev->iommu_bitmap_lock, flags);
         offset = __dma_alloc_iommu(zdev, zdev->next_bit, size);
-        if (offset == -1)
+        if (offset == -1) {
+                /* wrap-around */
                 offset = __dma_alloc_iommu(zdev, 0, size);
+                wrap = 1;
+        }
 
         if (offset != -1) {
                 zdev->next_bit = offset + size;
-                if (zdev->next_bit >= zdev->iommu_pages)
-                        zdev->next_bit = 0;
+                if (!zdev->tlb_refresh && !s390_iommu_strict && wrap)
+                        /* global flush after wrap-around with lazy unmap */
+                        zpci_refresh_global(zdev);
         }
         spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, flags);
         return offset;
@@ -243,7 +252,11 @@ static void dma_free_iommu(struct zpci_dev *zdev, unsigned long offset, int size
         if (!zdev->iommu_bitmap)
                 goto out;
         bitmap_clear(zdev->iommu_bitmap, offset, size);
-        if (offset >= zdev->next_bit)
+        /*
+         * Lazy flush for unmap: need to move next_bit to avoid address re-use
+         * until wrap-around.
+         */
+        if (!s390_iommu_strict && offset >= zdev->next_bit)
                 zdev->next_bit = offset + size;
 out:
         spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, flags);
@@ -504,3 +517,12 @@ struct dma_map_ops s390_dma_ops = {
         /* dma_supported is unconditionally true without a callback */
 };
 EXPORT_SYMBOL_GPL(s390_dma_ops);
+
+static int __init s390_iommu_setup(char *str)
+{
+        if (!strncmp(str, "strict", 6))
+                s390_iommu_strict = 1;
+        return 0;
+}
+
+__setup("s390_iommu=", s390_iommu_setup);
diff --git a/arch/s390/pci/pci_event.c b/arch/s390/pci/pci_event.c
index 6d7f5a3016ca..460fdb21cf61 100644
--- a/arch/s390/pci/pci_event.c
+++ b/arch/s390/pci/pci_event.c
@@ -5,8 +5,8 @@
  *    Jan Glauber <jang@linux.vnet.ibm.com>
  */
 
-#define COMPONENT "zPCI"
-#define pr_fmt(fmt) COMPONENT ": " fmt
+#define KMSG_COMPONENT "zpci"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
 #include <linux/kernel.h>
 #include <linux/pci.h>
diff --git a/arch/s390/pci/pci_sysfs.c b/arch/s390/pci/pci_sysfs.c
index 9190214b8702..fa3ce891e597 100644
--- a/arch/s390/pci/pci_sysfs.c
+++ b/arch/s390/pci/pci_sysfs.c
@@ -5,8 +5,8 @@
  *   Jan Glauber <jang@linux.vnet.ibm.com>
  */
 
-#define COMPONENT "zPCI"
-#define pr_fmt(fmt) COMPONENT ": " fmt
+#define KMSG_COMPONENT "zpci"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
 #include <linux/kernel.h>
 #include <linux/stat.h>