[v2,3/7] s390/pci: Use dma-iommu layer

Message ID 20221116171656.4128212-4-schnelle@linux.ibm.com
State New
Headers
Series iommu/dma: s390 DMA API conversion and optimized IOTLB flushing |

Commit Message

Niklas Schnelle Nov. 16, 2022, 5:16 p.m. UTC
  While s390 already has a standard IOMMU driver and previous changes have
added I/O TLB flushing operations this driver is currently only used for
user-space PCI access such as vfio-pci. For the DMA API s390 instead
utilizes its own implementation in arch/s390/pci/pci_dma.c which drives
the same hardware and shares some code but requires a complex and
fragile hand over between DMA API and IOMMU API use of a device and
despite code sharing still leads to significant duplication and
maintenance effort. Let's utilize the common code DMAP API
implementation from drivers/iommu/dma-iommu.c instead allowing us to
get rid of arch/s390/pci/pci_dma.c.

Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
---
 .../admin-guide/kernel-parameters.txt         |   9 +-
 arch/s390/include/asm/pci.h                   |   7 -
 arch/s390/include/asm/pci_dma.h               | 120 +--
 arch/s390/pci/Makefile                        |   2 +-
 arch/s390/pci/pci.c                           |  22 +-
 arch/s390/pci/pci_bus.c                       |   5 -
 arch/s390/pci/pci_debug.c                     |  13 +-
 arch/s390/pci/pci_dma.c                       | 732 ------------------
 arch/s390/pci/pci_event.c                     |   2 -
 arch/s390/pci/pci_sysfs.c                     |  19 +-
 drivers/iommu/Kconfig                         |   3 +-
 drivers/iommu/s390-iommu.c                    | 391 +++++++++-
 12 files changed, 408 insertions(+), 917 deletions(-)
 delete mode 100644 arch/s390/pci/pci_dma.c
  

Comments

Robin Murphy Nov. 28, 2022, 6:03 p.m. UTC | #1
On 2022-11-16 17:16, Niklas Schnelle wrote:
[...]
> diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
> index dc5f7a156ff5..804fb8f42d61 100644
> --- a/drivers/iommu/Kconfig
> +++ b/drivers/iommu/Kconfig
> @@ -93,7 +93,7 @@ config IOMMU_DEBUGFS
>   choice
>   	prompt "IOMMU default domain type"
>   	depends on IOMMU_API
> -	default IOMMU_DEFAULT_DMA_LAZY if X86 || IA64
> +	default IOMMU_DEFAULT_DMA_LAZY if X86 || IA64 || S390
>   	default IOMMU_DEFAULT_DMA_STRICT
>   	help
>   	  Choose the type of IOMMU domain used to manage DMA API usage by
> @@ -412,6 +412,7 @@ config ARM_SMMU_V3_SVA
>   config S390_IOMMU
>   	def_bool y if S390 && PCI
>   	depends on S390 && PCI
> +	select IOMMU_DMA

Please add S390 to the condition under config IOMMU_DMA instead.

>   	select IOMMU_API
>   	help
>   	  Support for the IOMMU API for s390 PCI devices.
[...]
> @@ -45,9 +329,14 @@ static struct iommu_domain *s390_domain_alloc(unsigned domain_type)
>   {
>   	struct s390_domain *s390_domain;
>   
> -	if (domain_type != IOMMU_DOMAIN_UNMANAGED)
> +	switch (domain_type) {
> +	case IOMMU_DOMAIN_DMA:
> +	case IOMMU_DOMAIN_DMA_FQ:

I was about to question adding this without any visible treatment of 
iommu_iotlb_gather_queued() or domain->type == IOMMU_DOMAIN_DMA_FQ as a 
whole, but I guess if you never actually free any pagetables it does 
work out OK. Bit of a timebomb if there's a chance of that ever changing 
in future, though.

> +	case IOMMU_DOMAIN_UNMANAGED:
> +		break;
> +	default:
>   		return NULL;
> -
> +	}
>   	s390_domain = kzalloc(sizeof(*s390_domain), GFP_KERNEL);
>   	if (!s390_domain)
>   		return NULL;
[...]
> @@ -397,12 +678,29 @@ static size_t s390_iommu_unmap_pages(struct iommu_domain *domain,
>   		return 0;
>   
>   	iommu_iotlb_gather_add_range(gather, iova, size);
> +	atomic64_add(pgcount, &s390_domain->ctrs.unmapped_pages);
>   
>   	return size;
>   }
>   
> +static void s390_iommu_probe_finalize(struct device *dev)
> +{
> +	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
> +
> +	iommu_dma_forcedac = true;
> +	iommu_setup_dma_ops(dev, domain->geometry.aperture_start, domain->geometry.aperture_end);

For consistency with all but one other caller now, just pass 0 and 
U64_MAX for base and size to make it clear that they're meaningless 
(they will eventually go away as part of a bigger refactoring).

Thanks,
Robin.
  
Niklas Schnelle Dec. 19, 2022, 3:17 p.m. UTC | #2
On Mon, 2022-11-28 at 18:03 +0000, Robin Murphy wrote:
> On 2022-11-16 17:16, Niklas Schnelle wrote:
> [...]
> > diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
> > index dc5f7a156ff5..804fb8f42d61 100644
> > --- a/drivers/iommu/Kconfig
> > +++ b/drivers/iommu/Kconfig
> > @@ -93,7 +93,7 @@ config IOMMU_DEBUGFS
> >   choice
> >   	prompt "IOMMU default domain type"
> >   	depends on IOMMU_API
> > -	default IOMMU_DEFAULT_DMA_LAZY if X86 || IA64
> > +	default IOMMU_DEFAULT_DMA_LAZY if X86 || IA64 || S390
> >   	default IOMMU_DEFAULT_DMA_STRICT
> >   	help
> >   	  Choose the type of IOMMU domain used to manage DMA API usage by
> > @@ -412,6 +412,7 @@ config ARM_SMMU_V3_SVA
> >   config S390_IOMMU
> >   	def_bool y if S390 && PCI
> >   	depends on S390 && PCI
> > +	select IOMMU_DMA
> 
> Please add S390 to the condition under config IOMMU_DMA instead.

Done, will be in v3

> 
> >   	select IOMMU_API
> >   	help
> >   	  Support for the IOMMU API for s390 PCI devices.
> [...]
> > @@ -45,9 +329,14 @@ static struct iommu_domain *s390_domain_alloc(unsigned domain_type)
> >   {
> >   	struct s390_domain *s390_domain;
> >   
> > -	if (domain_type != IOMMU_DOMAIN_UNMANAGED)
> > +	switch (domain_type) {
> > +	case IOMMU_DOMAIN_DMA:
> > +	case IOMMU_DOMAIN_DMA_FQ:
> 
> I was about to question adding this without any visible treatment of 
> iommu_iotlb_gather_queued() or domain->type == IOMMU_DOMAIN_DMA_FQ as a 
> whole, but I guess if you never actually free any pagetables it does 
> work out OK. Bit of a timebomb if there's a chance of that ever changing 
> in future, though.

Yes, as we're not freeing pagetables they will be reused simply by
reusing same IOVA. Restricting the range of IOVAs is then what keeps
the translation table from growing unbounded. This also makes the
pagetable handling easier 

It will definitely need handling if we ever add freeing pagestables
yes. I'd hope though that if we do add this functionality it will be
through common code reuse such as io-pgtable.h that will deal with this
naturally. I'm still pondering to add a comment here but I also fear
that this part is going to be refactored soon and such a comment will
get lost before it could matter.

> 
> > +	case IOMMU_DOMAIN_UNMANAGED:
> > +		break;
> > +	default:
> >   		return NULL;
> > -
> > +	}
> >   	s390_domain = kzalloc(sizeof(*s390_domain), GFP_KERNEL);
> >   	if (!s390_domain)
> >   		return NULL;
> [...]
> > @@ -397,12 +678,29 @@ static size_t s390_iommu_unmap_pages(struct iommu_domain *domain,
> >   		return 0;
> >   
> >   	iommu_iotlb_gather_add_range(gather, iova, size);
> > +	atomic64_add(pgcount, &s390_domain->ctrs.unmapped_pages);
> >   
> >   	return size;
> >   }
> >   
> > +static void s390_iommu_probe_finalize(struct device *dev)
> > +{
> > +	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
> > +
> > +	iommu_dma_forcedac = true;
> > +	iommu_setup_dma_ops(dev, domain->geometry.aperture_start, domain->geometry.aperture_end);
> 
> For consistency with all but one other caller now, just pass 0 and 
> U64_MAX for base and size to make it clear that they're meaningless 
> (they will eventually go away as part of a bigger refactoring).
> 
> Thanks,
> Robin.

Done will be in v3.

Now I'm still trying to figure out how to prefer the proposed
IOMMU_DOMAIN_DMA_SQ when running with a hypervisor with expensive IOTLB
flush while IOMMU_DOMAIN_DMA and IOMMU_DOMAIN_DMA_FQ both work but are
slower. Jason's patch idea of adding a DMA_API_POLICY sounds like a
good start but is also a rather big change and doesn't yet allow for a
preference by the IOMMU driver. Will see, if I can come up with
something minimal for that.
  

Patch

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index a465d5242774..633312c4f800 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2154,7 +2154,7 @@ 
 			  forcing Dual Address Cycle for PCI cards supporting
 			  greater than 32-bit addressing.
 
-	iommu.strict=	[ARM64, X86] Configure TLB invalidation behaviour
+	iommu.strict=	[ARM64, X86, S390] Configure TLB invalidation behaviour
 			Format: { "0" | "1" }
 			0 - Lazy mode.
 			  Request that DMA unmap operations use deferred
@@ -5387,9 +5387,10 @@ 
 	s390_iommu=	[HW,S390]
 			Set s390 IOTLB flushing mode
 		strict
-			With strict flushing every unmap operation will result in
-			an IOTLB flush. Default is lazy flushing before reuse,
-			which is faster.
+			With strict flushing every unmap operation will result
+			in an IOTLB flush. Default is lazy flushing before
+			reuse, which is faster. Deprecated, equivalent to
+			iommu.strict=1.
 
 	s390_iommu_aperture=	[KNL,S390]
 			Specifies the size of the per device DMA address space
diff --git a/arch/s390/include/asm/pci.h b/arch/s390/include/asm/pci.h
index b248694e0024..3f74f1cf37df 100644
--- a/arch/s390/include/asm/pci.h
+++ b/arch/s390/include/asm/pci.h
@@ -159,13 +159,6 @@  struct zpci_dev {
 	unsigned long	*dma_table;
 	int		tlb_refresh;
 
-	spinlock_t	iommu_bitmap_lock;
-	unsigned long	*iommu_bitmap;
-	unsigned long	*lazy_bitmap;
-	unsigned long	iommu_size;
-	unsigned long	iommu_pages;
-	unsigned int	next_bit;
-
 	struct iommu_device iommu_dev;  /* IOMMU core handle */
 
 	char res_name[16];
diff --git a/arch/s390/include/asm/pci_dma.h b/arch/s390/include/asm/pci_dma.h
index 91e63426bdc5..42d7cc4262ca 100644
--- a/arch/s390/include/asm/pci_dma.h
+++ b/arch/s390/include/asm/pci_dma.h
@@ -82,116 +82,16 @@  enum zpci_ioat_dtype {
 #define ZPCI_TABLE_VALID_MASK		0x20
 #define ZPCI_TABLE_PROT_MASK		0x200
 
-static inline unsigned int calc_rtx(dma_addr_t ptr)
-{
-	return ((unsigned long) ptr >> ZPCI_RT_SHIFT) & ZPCI_INDEX_MASK;
-}
-
-static inline unsigned int calc_sx(dma_addr_t ptr)
-{
-	return ((unsigned long) ptr >> ZPCI_ST_SHIFT) & ZPCI_INDEX_MASK;
-}
-
-static inline unsigned int calc_px(dma_addr_t ptr)
-{
-	return ((unsigned long) ptr >> PAGE_SHIFT) & ZPCI_PT_MASK;
-}
-
-static inline void set_pt_pfaa(unsigned long *entry, phys_addr_t pfaa)
-{
-	*entry &= ZPCI_PTE_FLAG_MASK;
-	*entry |= (pfaa & ZPCI_PTE_ADDR_MASK);
-}
-
-static inline void set_rt_sto(unsigned long *entry, phys_addr_t sto)
-{
-	*entry &= ZPCI_RTE_FLAG_MASK;
-	*entry |= (sto & ZPCI_RTE_ADDR_MASK);
-	*entry |= ZPCI_TABLE_TYPE_RTX;
-}
-
-static inline void set_st_pto(unsigned long *entry, phys_addr_t pto)
-{
-	*entry &= ZPCI_STE_FLAG_MASK;
-	*entry |= (pto & ZPCI_STE_ADDR_MASK);
-	*entry |= ZPCI_TABLE_TYPE_SX;
-}
-
-static inline void validate_rt_entry(unsigned long *entry)
-{
-	*entry &= ~ZPCI_TABLE_VALID_MASK;
-	*entry &= ~ZPCI_TABLE_OFFSET_MASK;
-	*entry |= ZPCI_TABLE_VALID;
-	*entry |= ZPCI_TABLE_LEN_RTX;
-}
-
-static inline void validate_st_entry(unsigned long *entry)
-{
-	*entry &= ~ZPCI_TABLE_VALID_MASK;
-	*entry |= ZPCI_TABLE_VALID;
-}
-
-static inline void invalidate_pt_entry(unsigned long *entry)
-{
-	WARN_ON_ONCE((*entry & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_INVALID);
-	*entry &= ~ZPCI_PTE_VALID_MASK;
-	*entry |= ZPCI_PTE_INVALID;
-}
-
-static inline void validate_pt_entry(unsigned long *entry)
-{
-	WARN_ON_ONCE((*entry & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID);
-	*entry &= ~ZPCI_PTE_VALID_MASK;
-	*entry |= ZPCI_PTE_VALID;
-}
-
-static inline void entry_set_protected(unsigned long *entry)
-{
-	*entry &= ~ZPCI_TABLE_PROT_MASK;
-	*entry |= ZPCI_TABLE_PROTECTED;
-}
-
-static inline void entry_clr_protected(unsigned long *entry)
-{
-	*entry &= ~ZPCI_TABLE_PROT_MASK;
-	*entry |= ZPCI_TABLE_UNPROTECTED;
-}
-
-static inline int reg_entry_isvalid(unsigned long entry)
-{
-	return (entry & ZPCI_TABLE_VALID_MASK) == ZPCI_TABLE_VALID;
-}
-
-static inline int pt_entry_isvalid(unsigned long entry)
-{
-	return (entry & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID;
-}
-
-static inline unsigned long *get_rt_sto(unsigned long entry)
-{
-	if ((entry & ZPCI_TABLE_TYPE_MASK) == ZPCI_TABLE_TYPE_RTX)
-		return phys_to_virt(entry & ZPCI_RTE_ADDR_MASK);
-	else
-		return NULL;
-
-}
-
-static inline unsigned long *get_st_pto(unsigned long entry)
-{
-	if ((entry & ZPCI_TABLE_TYPE_MASK) == ZPCI_TABLE_TYPE_SX)
-		return phys_to_virt(entry & ZPCI_STE_ADDR_MASK);
-	else
-		return NULL;
-}
-
-/* Prototypes */
-void dma_free_seg_table(unsigned long);
-unsigned long *dma_alloc_cpu_table(void);
-void dma_cleanup_tables(unsigned long *);
-unsigned long *dma_walk_cpu_trans(unsigned long *rto, dma_addr_t dma_addr);
-void dma_update_cpu_trans(unsigned long *entry, phys_addr_t page_addr, int flags);
-
-extern const struct dma_map_ops s390_pci_dma_ops;
+struct zpci_iommu_ctrs {
+	atomic64_t		mapped_pages;
+	atomic64_t		unmapped_pages;
+	atomic64_t		global_rpcits;
+	atomic64_t		sync_map_rpcits;
+	atomic64_t		sync_rpcits;
+};
+
+struct zpci_dev;
 
+struct zpci_iommu_ctrs *zpci_get_iommu_ctrs(struct zpci_dev *zdev);
 
 #endif
diff --git a/arch/s390/pci/Makefile b/arch/s390/pci/Makefile
index 5ae31ca9dd44..0547a10406e7 100644
--- a/arch/s390/pci/Makefile
+++ b/arch/s390/pci/Makefile
@@ -3,7 +3,7 @@ 
 # Makefile for the s390 PCI subsystem.
 #
 
-obj-$(CONFIG_PCI)	+= pci.o pci_irq.o pci_dma.o pci_clp.o pci_sysfs.o \
+obj-$(CONFIG_PCI)	+= pci.o pci_irq.o pci_clp.o pci_sysfs.o \
 			   pci_event.o pci_debug.o pci_insn.o pci_mmio.o \
 			   pci_bus.o pci_kvm_hook.o
 obj-$(CONFIG_PCI_IOV)	+= pci_iov.o
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index ef38b1514c77..6b0fe8761509 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -124,7 +124,11 @@  int zpci_register_ioat(struct zpci_dev *zdev, u8 dmaas,
 
 	WARN_ON_ONCE(iota & 0x3fff);
 	fib.pba = base;
-	fib.pal = limit;
+	/* Work around off by one in ISM virt device */
+	if (zdev->pft == 0x5 && limit > base)
+		fib.pal = limit + (1 << 12);
+	else
+		fib.pal = limit;
 	fib.iota = iota | ZPCI_IOTA_RTTO_FLAG;
 	fib.gd = zdev->gisa;
 	cc = zpci_mod_fc(req, &fib, status);
@@ -615,7 +619,6 @@  int pcibios_device_add(struct pci_dev *pdev)
 		pdev->no_vf_scan = 1;
 
 	pdev->dev.groups = zpci_attr_groups;
-	pdev->dev.dma_ops = &s390_pci_dma_ops;
 	zpci_map_resources(pdev);
 
 	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
@@ -789,8 +792,6 @@  int zpci_hot_reset_device(struct zpci_dev *zdev)
 	if (zdev->dma_table)
 		rc = zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
 					virt_to_phys(zdev->dma_table), &status);
-	else
-		rc = zpci_dma_init_device(zdev);
 	if (rc) {
 		zpci_disable_device(zdev);
 		return rc;
@@ -915,11 +916,6 @@  int zpci_deconfigure_device(struct zpci_dev *zdev)
 	if (zdev->zbus->bus)
 		zpci_bus_remove_device(zdev, false);
 
-	if (zdev->dma_table) {
-		rc = zpci_dma_exit_device(zdev);
-		if (rc)
-			return rc;
-	}
 	if (zdev_enabled(zdev)) {
 		rc = zpci_disable_device(zdev);
 		if (rc)
@@ -968,8 +964,6 @@  void zpci_release_device(struct kref *kref)
 	if (zdev->zbus->bus)
 		zpci_bus_remove_device(zdev, false);
 
-	if (zdev->dma_table)
-		zpci_dma_exit_device(zdev);
 	if (zdev_enabled(zdev))
 		zpci_disable_device(zdev);
 
@@ -1159,10 +1153,6 @@  static int __init pci_base_init(void)
 	if (rc)
 		goto out_irq;
 
-	rc = zpci_dma_init();
-	if (rc)
-		goto out_dma;
-
 	rc = clp_scan_pci_devices();
 	if (rc)
 		goto out_find;
@@ -1172,8 +1162,6 @@  static int __init pci_base_init(void)
 	return 0;
 
 out_find:
-	zpci_dma_exit();
-out_dma:
 	zpci_irq_exit();
 out_irq:
 	zpci_mem_exit();
diff --git a/arch/s390/pci/pci_bus.c b/arch/s390/pci/pci_bus.c
index 6a8da1b742ae..b15ad15999f8 100644
--- a/arch/s390/pci/pci_bus.c
+++ b/arch/s390/pci/pci_bus.c
@@ -49,11 +49,6 @@  static int zpci_bus_prepare_device(struct zpci_dev *zdev)
 		rc = zpci_enable_device(zdev);
 		if (rc)
 			return rc;
-		rc = zpci_dma_init_device(zdev);
-		if (rc) {
-			zpci_disable_device(zdev);
-			return rc;
-		}
 	}
 
 	if (!zdev->has_resources) {
diff --git a/arch/s390/pci/pci_debug.c b/arch/s390/pci/pci_debug.c
index ca6bd98eec13..60cec57a3907 100644
--- a/arch/s390/pci/pci_debug.c
+++ b/arch/s390/pci/pci_debug.c
@@ -53,9 +53,12 @@  static char *pci_fmt3_names[] = {
 };
 
 static char *pci_sw_names[] = {
-	"Allocated pages",
+/* TODO "Allocated pages", */
 	"Mapped pages",
 	"Unmapped pages",
+	"Global RPCITs",
+	"Sync Map RPCITs",
+	"Sync RPCITs",
 };
 
 static void pci_fmb_show(struct seq_file *m, char *name[], int length,
@@ -69,10 +72,14 @@  static void pci_fmb_show(struct seq_file *m, char *name[], int length,
 
 static void pci_sw_counter_show(struct seq_file *m)
 {
-	struct zpci_dev *zdev = m->private;
-	atomic64_t *counter = &zdev->allocated_pages;
+	struct zpci_iommu_ctrs  *ctrs = zpci_get_iommu_ctrs(m->private);
+	atomic64_t *counter;
 	int i;
 
+	if (!ctrs)
+		return;
+
+	counter = &ctrs->mapped_pages;
 	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));
diff --git a/arch/s390/pci/pci_dma.c b/arch/s390/pci/pci_dma.c
deleted file mode 100644
index ea478d11fbd1..000000000000
--- a/arch/s390/pci/pci_dma.c
+++ /dev/null
@@ -1,732 +0,0 @@ 
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright IBM Corp. 2012
- *
- * Author(s):
- *   Jan Glauber <jang@linux.vnet.ibm.com>
- */
-
-#include <linux/kernel.h>
-#include <linux/slab.h>
-#include <linux/export.h>
-#include <linux/iommu-helper.h>
-#include <linux/dma-map-ops.h>
-#include <linux/vmalloc.h>
-#include <linux/pci.h>
-#include <asm/pci_dma.h>
-
-static struct kmem_cache *dma_region_table_cache;
-static struct kmem_cache *dma_page_table_cache;
-static int s390_iommu_strict;
-static u64 s390_iommu_aperture;
-static u32 s390_iommu_aperture_factor = 1;
-
-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);
-}
-
-unsigned long *dma_alloc_cpu_table(void)
-{
-	unsigned long *table, *entry;
-
-	table = kmem_cache_alloc(dma_region_table_cache, GFP_ATOMIC);
-	if (!table)
-		return NULL;
-
-	for (entry = table; entry < table + ZPCI_TABLE_ENTRIES; entry++)
-		*entry = ZPCI_TABLE_INVALID;
-	return table;
-}
-
-static void dma_free_cpu_table(void *table)
-{
-	kmem_cache_free(dma_region_table_cache, table);
-}
-
-static unsigned long *dma_alloc_page_table(void)
-{
-	unsigned long *table, *entry;
-
-	table = kmem_cache_alloc(dma_page_table_cache, GFP_ATOMIC);
-	if (!table)
-		return NULL;
-
-	for (entry = table; entry < table + ZPCI_PT_ENTRIES; entry++)
-		*entry = ZPCI_PTE_INVALID;
-	return table;
-}
-
-static void dma_free_page_table(void *table)
-{
-	kmem_cache_free(dma_page_table_cache, table);
-}
-
-static unsigned long *dma_get_seg_table_origin(unsigned long *rtep)
-{
-	unsigned long old_rte, rte;
-	unsigned long *sto;
-
-	rte = READ_ONCE(*rtep);
-	if (reg_entry_isvalid(rte)) {
-		sto = get_rt_sto(rte);
-	} else {
-		sto = dma_alloc_cpu_table();
-		if (!sto)
-			return NULL;
-
-		set_rt_sto(&rte, virt_to_phys(sto));
-		validate_rt_entry(&rte);
-		entry_clr_protected(&rte);
-
-		old_rte = cmpxchg(rtep, ZPCI_TABLE_INVALID, rte);
-		if (old_rte != ZPCI_TABLE_INVALID) {
-			/* Somone else was faster, use theirs */
-			dma_free_cpu_table(sto);
-			sto = get_rt_sto(old_rte);
-		}
-	}
-	return sto;
-}
-
-static unsigned long *dma_get_page_table_origin(unsigned long *step)
-{
-	unsigned long old_ste, ste;
-	unsigned long *pto;
-
-	ste = READ_ONCE(*step);
-	if (reg_entry_isvalid(ste)) {
-		pto = get_st_pto(ste);
-	} else {
-		pto = dma_alloc_page_table();
-		if (!pto)
-			return NULL;
-		set_st_pto(&ste, virt_to_phys(pto));
-		validate_st_entry(&ste);
-		entry_clr_protected(&ste);
-
-		old_ste = cmpxchg(step, ZPCI_TABLE_INVALID, ste);
-		if (old_ste != ZPCI_TABLE_INVALID) {
-			/* Somone else was faster, use theirs */
-			dma_free_page_table(pto);
-			pto = get_st_pto(old_ste);
-		}
-	}
-	return pto;
-}
-
-unsigned long *dma_walk_cpu_trans(unsigned long *rto, dma_addr_t dma_addr)
-{
-	unsigned long *sto, *pto;
-	unsigned int rtx, sx, px;
-
-	rtx = calc_rtx(dma_addr);
-	sto = dma_get_seg_table_origin(&rto[rtx]);
-	if (!sto)
-		return NULL;
-
-	sx = calc_sx(dma_addr);
-	pto = dma_get_page_table_origin(&sto[sx]);
-	if (!pto)
-		return NULL;
-
-	px = calc_px(dma_addr);
-	return &pto[px];
-}
-
-void dma_update_cpu_trans(unsigned long *ptep, phys_addr_t page_addr, int flags)
-{
-	unsigned long pte;
-
-	pte = READ_ONCE(*ptep);
-	if (flags & ZPCI_PTE_INVALID) {
-		invalidate_pt_entry(&pte);
-	} else {
-		set_pt_pfaa(&pte, page_addr);
-		validate_pt_entry(&pte);
-	}
-
-	if (flags & ZPCI_TABLE_PROTECTED)
-		entry_set_protected(&pte);
-	else
-		entry_clr_protected(&pte);
-
-	xchg(ptep, pte);
-}
-
-static int __dma_update_trans(struct zpci_dev *zdev, phys_addr_t pa,
-			      dma_addr_t dma_addr, size_t size, int flags)
-{
-	unsigned int nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
-	phys_addr_t page_addr = (pa & PAGE_MASK);
-	unsigned long *entry;
-	int i, rc = 0;
-
-	if (!nr_pages)
-		return -EINVAL;
-
-	if (!zdev->dma_table)
-		return -EINVAL;
-
-	for (i = 0; i < nr_pages; i++) {
-		entry = dma_walk_cpu_trans(zdev->dma_table, dma_addr);
-		if (!entry) {
-			rc = -ENOMEM;
-			goto undo_cpu_trans;
-		}
-		dma_update_cpu_trans(entry, page_addr, flags);
-		page_addr += PAGE_SIZE;
-		dma_addr += PAGE_SIZE;
-	}
-
-undo_cpu_trans:
-	if (rc && ((flags & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID)) {
-		flags = ZPCI_PTE_INVALID;
-		while (i-- > 0) {
-			page_addr -= PAGE_SIZE;
-			dma_addr -= PAGE_SIZE;
-			entry = dma_walk_cpu_trans(zdev->dma_table, dma_addr);
-			if (!entry)
-				break;
-			dma_update_cpu_trans(entry, page_addr, flags);
-		}
-	}
-	return rc;
-}
-
-static int __dma_purge_tlb(struct zpci_dev *zdev, dma_addr_t dma_addr,
-			   size_t size, int flags)
-{
-	unsigned long irqflags;
-	int ret;
-
-	/*
-	 * With zdev->tlb_refresh == 0, rpcit is not required to establish new
-	 * translations when previously invalid translation-table entries are
-	 * validated. With lazy unmap, rpcit 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 ((flags & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID) {
-		if (!zdev->tlb_refresh)
-			return 0;
-	} else {
-		if (!s390_iommu_strict)
-			return 0;
-	}
-
-	ret = zpci_refresh_trans((u64) zdev->fh << 32, dma_addr,
-				 PAGE_ALIGN(size));
-	if (ret == -ENOMEM && !s390_iommu_strict) {
-		/* enable the hypervisor to free some resources */
-		if (zpci_refresh_global(zdev))
-			goto out;
-
-		spin_lock_irqsave(&zdev->iommu_bitmap_lock, irqflags);
-		bitmap_andnot(zdev->iommu_bitmap, zdev->iommu_bitmap,
-			      zdev->lazy_bitmap, zdev->iommu_pages);
-		bitmap_zero(zdev->lazy_bitmap, zdev->iommu_pages);
-		spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, irqflags);
-		ret = 0;
-	}
-out:
-	return ret;
-}
-
-static int dma_update_trans(struct zpci_dev *zdev, phys_addr_t pa,
-			    dma_addr_t dma_addr, size_t size, int flags)
-{
-	int rc;
-
-	rc = __dma_update_trans(zdev, pa, dma_addr, size, flags);
-	if (rc)
-		return rc;
-
-	rc = __dma_purge_tlb(zdev, dma_addr, size, flags);
-	if (rc && ((flags & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID))
-		__dma_update_trans(zdev, pa, dma_addr, size, ZPCI_PTE_INVALID);
-
-	return rc;
-}
-
-void dma_free_seg_table(unsigned long entry)
-{
-	unsigned long *sto = get_rt_sto(entry);
-	int sx;
-
-	for (sx = 0; sx < ZPCI_TABLE_ENTRIES; sx++)
-		if (reg_entry_isvalid(sto[sx]))
-			dma_free_page_table(get_st_pto(sto[sx]));
-
-	dma_free_cpu_table(sto);
-}
-
-void dma_cleanup_tables(unsigned long *table)
-{
-	int rtx;
-
-	if (!table)
-		return;
-
-	for (rtx = 0; rtx < ZPCI_TABLE_ENTRIES; rtx++)
-		if (reg_entry_isvalid(table[rtx]))
-			dma_free_seg_table(table[rtx]);
-
-	dma_free_cpu_table(table);
-}
-
-static unsigned long __dma_alloc_iommu(struct device *dev,
-				       unsigned long start, int size)
-{
-	struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
-
-	return iommu_area_alloc(zdev->iommu_bitmap, zdev->iommu_pages,
-				start, size, zdev->start_dma >> PAGE_SHIFT,
-				dma_get_seg_boundary_nr_pages(dev, PAGE_SHIFT),
-				0);
-}
-
-static dma_addr_t dma_alloc_address(struct device *dev, int size)
-{
-	struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
-	unsigned long offset, flags;
-
-	spin_lock_irqsave(&zdev->iommu_bitmap_lock, flags);
-	offset = __dma_alloc_iommu(dev, zdev->next_bit, size);
-	if (offset == -1) {
-		if (!s390_iommu_strict) {
-			/* global flush before DMA addresses are reused */
-			if (zpci_refresh_global(zdev))
-				goto out_error;
-
-			bitmap_andnot(zdev->iommu_bitmap, zdev->iommu_bitmap,
-				      zdev->lazy_bitmap, zdev->iommu_pages);
-			bitmap_zero(zdev->lazy_bitmap, zdev->iommu_pages);
-		}
-		/* wrap-around */
-		offset = __dma_alloc_iommu(dev, 0, size);
-		if (offset == -1)
-			goto out_error;
-	}
-	zdev->next_bit = offset + size;
-	spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, flags);
-
-	return zdev->start_dma + offset * PAGE_SIZE;
-
-out_error:
-	spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, flags);
-	return DMA_MAPPING_ERROR;
-}
-
-static void dma_free_address(struct device *dev, dma_addr_t dma_addr, int size)
-{
-	struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
-	unsigned long flags, offset;
-
-	offset = (dma_addr - zdev->start_dma) >> PAGE_SHIFT;
-
-	spin_lock_irqsave(&zdev->iommu_bitmap_lock, flags);
-	if (!zdev->iommu_bitmap)
-		goto out;
-
-	if (s390_iommu_strict)
-		bitmap_clear(zdev->iommu_bitmap, offset, size);
-	else
-		bitmap_set(zdev->lazy_bitmap, offset, size);
-
-out:
-	spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, flags);
-}
-
-static inline void zpci_err_dma(unsigned long rc, unsigned long addr)
-{
-	struct {
-		unsigned long rc;
-		unsigned long addr;
-	} __packed data = {rc, addr};
-
-	zpci_err_hex(&data, sizeof(data));
-}
-
-static dma_addr_t s390_dma_map_pages(struct device *dev, struct page *page,
-				     unsigned long offset, size_t size,
-				     enum dma_data_direction direction,
-				     unsigned long attrs)
-{
-	struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
-	unsigned long pa = page_to_phys(page) + offset;
-	int flags = ZPCI_PTE_VALID;
-	unsigned long nr_pages;
-	dma_addr_t dma_addr;
-	int ret;
-
-	/* This rounds up number of pages based on size and offset */
-	nr_pages = iommu_num_pages(pa, size, PAGE_SIZE);
-	dma_addr = dma_alloc_address(dev, nr_pages);
-	if (dma_addr == DMA_MAPPING_ERROR) {
-		ret = -ENOSPC;
-		goto out_err;
-	}
-
-	/* Use rounded up size */
-	size = nr_pages * PAGE_SIZE;
-
-	if (direction == DMA_NONE || direction == DMA_TO_DEVICE)
-		flags |= ZPCI_TABLE_PROTECTED;
-
-	ret = dma_update_trans(zdev, pa, dma_addr, size, flags);
-	if (ret)
-		goto out_free;
-
-	atomic64_add(nr_pages, &zdev->mapped_pages);
-	return dma_addr + (offset & ~PAGE_MASK);
-
-out_free:
-	dma_free_address(dev, dma_addr, nr_pages);
-out_err:
-	zpci_err("map error:\n");
-	zpci_err_dma(ret, pa);
-	return DMA_MAPPING_ERROR;
-}
-
-static void s390_dma_unmap_pages(struct device *dev, dma_addr_t dma_addr,
-				 size_t size, enum dma_data_direction direction,
-				 unsigned long attrs)
-{
-	struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
-	int npages, ret;
-
-	npages = iommu_num_pages(dma_addr, size, PAGE_SIZE);
-	dma_addr = dma_addr & PAGE_MASK;
-	ret = dma_update_trans(zdev, 0, dma_addr, npages * PAGE_SIZE,
-			       ZPCI_PTE_INVALID);
-	if (ret) {
-		zpci_err("unmap error:\n");
-		zpci_err_dma(ret, dma_addr);
-		return;
-	}
-
-	atomic64_add(npages, &zdev->unmapped_pages);
-	dma_free_address(dev, dma_addr, npages);
-}
-
-static void *s390_dma_alloc(struct device *dev, size_t size,
-			    dma_addr_t *dma_handle, gfp_t flag,
-			    unsigned long attrs)
-{
-	struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
-	struct page *page;
-	phys_addr_t pa;
-	dma_addr_t map;
-
-	size = PAGE_ALIGN(size);
-	page = alloc_pages(flag | __GFP_ZERO, get_order(size));
-	if (!page)
-		return NULL;
-
-	pa = page_to_phys(page);
-	map = s390_dma_map_pages(dev, page, 0, size, DMA_BIDIRECTIONAL, 0);
-	if (dma_mapping_error(dev, map)) {
-		__free_pages(page, get_order(size));
-		return NULL;
-	}
-
-	atomic64_add(size / PAGE_SIZE, &zdev->allocated_pages);
-	if (dma_handle)
-		*dma_handle = map;
-	return phys_to_virt(pa);
-}
-
-static void s390_dma_free(struct device *dev, size_t size,
-			  void *vaddr, dma_addr_t dma_handle,
-			  unsigned long attrs)
-{
-	struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
-
-	size = PAGE_ALIGN(size);
-	atomic64_sub(size / PAGE_SIZE, &zdev->allocated_pages);
-	s390_dma_unmap_pages(dev, dma_handle, size, DMA_BIDIRECTIONAL, 0);
-	free_pages((unsigned long)vaddr, get_order(size));
-}
-
-/* Map a segment into a contiguous dma address area */
-static int __s390_dma_map_sg(struct device *dev, struct scatterlist *sg,
-			     size_t size, dma_addr_t *handle,
-			     enum dma_data_direction dir)
-{
-	unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
-	struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
-	dma_addr_t dma_addr_base, dma_addr;
-	int flags = ZPCI_PTE_VALID;
-	struct scatterlist *s;
-	phys_addr_t pa = 0;
-	int ret;
-
-	dma_addr_base = dma_alloc_address(dev, nr_pages);
-	if (dma_addr_base == DMA_MAPPING_ERROR)
-		return -ENOMEM;
-
-	dma_addr = dma_addr_base;
-	if (dir == DMA_NONE || dir == DMA_TO_DEVICE)
-		flags |= ZPCI_TABLE_PROTECTED;
-
-	for (s = sg; dma_addr < dma_addr_base + size; s = sg_next(s)) {
-		pa = page_to_phys(sg_page(s));
-		ret = __dma_update_trans(zdev, pa, dma_addr,
-					 s->offset + s->length, flags);
-		if (ret)
-			goto unmap;
-
-		dma_addr += s->offset + s->length;
-	}
-	ret = __dma_purge_tlb(zdev, dma_addr_base, size, flags);
-	if (ret)
-		goto unmap;
-
-	*handle = dma_addr_base;
-	atomic64_add(nr_pages, &zdev->mapped_pages);
-
-	return ret;
-
-unmap:
-	dma_update_trans(zdev, 0, dma_addr_base, dma_addr - dma_addr_base,
-			 ZPCI_PTE_INVALID);
-	dma_free_address(dev, dma_addr_base, nr_pages);
-	zpci_err("map error:\n");
-	zpci_err_dma(ret, pa);
-	return ret;
-}
-
-static int s390_dma_map_sg(struct device *dev, struct scatterlist *sg,
-			   int nr_elements, enum dma_data_direction dir,
-			   unsigned long attrs)
-{
-	struct scatterlist *s = sg, *start = sg, *dma = sg;
-	unsigned int max = dma_get_max_seg_size(dev);
-	unsigned int size = s->offset + s->length;
-	unsigned int offset = s->offset;
-	int count = 0, i, ret;
-
-	for (i = 1; i < nr_elements; i++) {
-		s = sg_next(s);
-
-		s->dma_length = 0;
-
-		if (s->offset || (size & ~PAGE_MASK) ||
-		    size + s->length > max) {
-			ret = __s390_dma_map_sg(dev, start, size,
-						&dma->dma_address, dir);
-			if (ret)
-				goto unmap;
-
-			dma->dma_address += offset;
-			dma->dma_length = size - offset;
-
-			size = offset = s->offset;
-			start = s;
-			dma = sg_next(dma);
-			count++;
-		}
-		size += s->length;
-	}
-	ret = __s390_dma_map_sg(dev, start, size, &dma->dma_address, dir);
-	if (ret)
-		goto unmap;
-
-	dma->dma_address += offset;
-	dma->dma_length = size - offset;
-
-	return count + 1;
-unmap:
-	for_each_sg(sg, s, count, i)
-		s390_dma_unmap_pages(dev, sg_dma_address(s), sg_dma_len(s),
-				     dir, attrs);
-
-	return ret;
-}
-
-static void s390_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
-			      int nr_elements, enum dma_data_direction dir,
-			      unsigned long attrs)
-{
-	struct scatterlist *s;
-	int i;
-
-	for_each_sg(sg, s, nr_elements, i) {
-		if (s->dma_length)
-			s390_dma_unmap_pages(dev, s->dma_address, s->dma_length,
-					     dir, attrs);
-		s->dma_address = 0;
-		s->dma_length = 0;
-	}
-}
-	
-int zpci_dma_init_device(struct zpci_dev *zdev)
-{
-	u8 status;
-	int rc;
-
-	/*
-	 * At this point, if the device is part of an IOMMU domain, this would
-	 * be a strong hint towards a bug in the IOMMU API (common) code and/or
-	 * simultaneous access via IOMMU and DMA API. So let's issue a warning.
-	 */
-	WARN_ON(zdev->s390_domain);
-
-	spin_lock_init(&zdev->iommu_bitmap_lock);
-
-	zdev->dma_table = dma_alloc_cpu_table();
-	if (!zdev->dma_table) {
-		rc = -ENOMEM;
-		goto out;
-	}
-
-	/*
-	 * Restrict the iommu bitmap size to the minimum of the following:
-	 * - s390_iommu_aperture which defaults to high_memory
-	 * - 3-level pagetable address limit minus start_dma offset
-	 * - DMA address range allowed by the hardware (clp query pci fn)
-	 *
-	 * Also set zdev->end_dma to the actual end address of the usable
-	 * range, instead of the theoretical maximum as reported by hardware.
-	 *
-	 * This limits the number of concurrently usable DMA mappings since
-	 * for each DMA mapped memory address we need a DMA address including
-	 * extra DMA addresses for multiple mappings of the same memory address.
-	 */
-	zdev->start_dma = PAGE_ALIGN(zdev->start_dma);
-	zdev->iommu_size = min3(s390_iommu_aperture,
-				ZPCI_TABLE_SIZE_RT - zdev->start_dma,
-				zdev->end_dma - zdev->start_dma + 1);
-	zdev->end_dma = zdev->start_dma + zdev->iommu_size - 1;
-	zdev->iommu_pages = zdev->iommu_size >> PAGE_SHIFT;
-	zdev->iommu_bitmap = vzalloc(zdev->iommu_pages / 8);
-	if (!zdev->iommu_bitmap) {
-		rc = -ENOMEM;
-		goto free_dma_table;
-	}
-	if (!s390_iommu_strict) {
-		zdev->lazy_bitmap = vzalloc(zdev->iommu_pages / 8);
-		if (!zdev->lazy_bitmap) {
-			rc = -ENOMEM;
-			goto free_bitmap;
-		}
-
-	}
-	if (zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
-			       virt_to_phys(zdev->dma_table), &status)) {
-		rc = -EIO;
-		goto free_bitmap;
-	}
-
-	return 0;
-free_bitmap:
-	vfree(zdev->iommu_bitmap);
-	zdev->iommu_bitmap = NULL;
-	vfree(zdev->lazy_bitmap);
-	zdev->lazy_bitmap = NULL;
-free_dma_table:
-	dma_free_cpu_table(zdev->dma_table);
-	zdev->dma_table = NULL;
-out:
-	return rc;
-}
-
-int zpci_dma_exit_device(struct zpci_dev *zdev)
-{
-	int cc = 0;
-
-	/*
-	 * At this point, if the device is part of an IOMMU domain, this would
-	 * be a strong hint towards a bug in the IOMMU API (common) code and/or
-	 * simultaneous access via IOMMU and DMA API. So let's issue a warning.
-	 */
-	WARN_ON(zdev->s390_domain);
-	if (zdev_enabled(zdev))
-		cc = zpci_unregister_ioat(zdev, 0);
-	/*
-	 * cc == 3 indicates the function is gone already. This can happen
-	 * if the function was deconfigured/disabled suddenly and we have not
-	 * received a new handle yet.
-	 */
-	if (cc && cc != 3)
-		return -EIO;
-
-	dma_cleanup_tables(zdev->dma_table);
-	zdev->dma_table = NULL;
-	vfree(zdev->iommu_bitmap);
-	zdev->iommu_bitmap = NULL;
-	vfree(zdev->lazy_bitmap);
-	zdev->lazy_bitmap = NULL;
-	zdev->next_bit = 0;
-	return 0;
-}
-
-static int __init dma_alloc_cpu_table_caches(void)
-{
-	dma_region_table_cache = kmem_cache_create("PCI_DMA_region_tables",
-					ZPCI_TABLE_SIZE, ZPCI_TABLE_ALIGN,
-					0, NULL);
-	if (!dma_region_table_cache)
-		return -ENOMEM;
-
-	dma_page_table_cache = kmem_cache_create("PCI_DMA_page_tables",
-					ZPCI_PT_SIZE, ZPCI_PT_ALIGN,
-					0, NULL);
-	if (!dma_page_table_cache) {
-		kmem_cache_destroy(dma_region_table_cache);
-		return -ENOMEM;
-	}
-	return 0;
-}
-
-int __init zpci_dma_init(void)
-{
-	s390_iommu_aperture = (u64)virt_to_phys(high_memory);
-	if (!s390_iommu_aperture_factor)
-		s390_iommu_aperture = ULONG_MAX;
-	else
-		s390_iommu_aperture *= s390_iommu_aperture_factor;
-
-	return dma_alloc_cpu_table_caches();
-}
-
-void zpci_dma_exit(void)
-{
-	kmem_cache_destroy(dma_page_table_cache);
-	kmem_cache_destroy(dma_region_table_cache);
-}
-
-const struct dma_map_ops s390_pci_dma_ops = {
-	.alloc		= s390_dma_alloc,
-	.free		= s390_dma_free,
-	.map_sg		= s390_dma_map_sg,
-	.unmap_sg	= s390_dma_unmap_sg,
-	.map_page	= s390_dma_map_pages,
-	.unmap_page	= s390_dma_unmap_pages,
-	.mmap		= dma_common_mmap,
-	.get_sgtable	= dma_common_get_sgtable,
-	.alloc_pages	= dma_common_alloc_pages,
-	.free_pages	= dma_common_free_pages,
-	/* dma_supported is unconditionally true without a callback */
-};
-EXPORT_SYMBOL_GPL(s390_pci_dma_ops);
-
-static int __init s390_iommu_setup(char *str)
-{
-	if (!strcmp(str, "strict"))
-		s390_iommu_strict = 1;
-	return 1;
-}
-
-__setup("s390_iommu=", s390_iommu_setup);
-
-static int __init s390_iommu_aperture_setup(char *str)
-{
-	if (kstrtou32(str, 10, &s390_iommu_aperture_factor))
-		s390_iommu_aperture_factor = 1;
-	return 1;
-}
-
-__setup("s390_iommu_aperture=", s390_iommu_aperture_setup);
diff --git a/arch/s390/pci/pci_event.c b/arch/s390/pci/pci_event.c
index 4ef5a6a1d618..4d9773ef9e0a 100644
--- a/arch/s390/pci/pci_event.c
+++ b/arch/s390/pci/pci_event.c
@@ -313,8 +313,6 @@  static void zpci_event_hard_deconfigured(struct zpci_dev *zdev, u32 fh)
 	/* Even though the device is already gone we still
 	 * need to free zPCI resources as part of the disable.
 	 */
-	if (zdev->dma_table)
-		zpci_dma_exit_device(zdev);
 	if (zdev_enabled(zdev))
 		zpci_disable_device(zdev);
 	zdev->state = ZPCI_FN_STATE_STANDBY;
diff --git a/arch/s390/pci/pci_sysfs.c b/arch/s390/pci/pci_sysfs.c
index cae280e5c047..8a7abac51816 100644
--- a/arch/s390/pci/pci_sysfs.c
+++ b/arch/s390/pci/pci_sysfs.c
@@ -56,6 +56,7 @@  static ssize_t recover_store(struct device *dev, struct device_attribute *attr,
 	struct pci_dev *pdev = to_pci_dev(dev);
 	struct zpci_dev *zdev = to_zpci(pdev);
 	int ret = 0;
+	u8 status;
 
 	/* Can't use device_remove_self() here as that would lead us to lock
 	 * the pci_rescan_remove_lock while holding the device' kernfs lock.
@@ -82,12 +83,6 @@  static ssize_t recover_store(struct device *dev, struct device_attribute *attr,
 	pci_lock_rescan_remove();
 	if (pci_dev_is_added(pdev)) {
 		pci_stop_and_remove_bus_device(pdev);
-		if (zdev->dma_table) {
-			ret = zpci_dma_exit_device(zdev);
-			if (ret)
-				goto out;
-		}
-
 		if (zdev_enabled(zdev)) {
 			ret = zpci_disable_device(zdev);
 			/*
@@ -105,14 +100,16 @@  static ssize_t recover_store(struct device *dev, struct device_attribute *attr,
 		ret = zpci_enable_device(zdev);
 		if (ret)
 			goto out;
-		ret = zpci_dma_init_device(zdev);
-		if (ret) {
-			zpci_disable_device(zdev);
-			goto out;
+
+		if (zdev->dma_table) {
+			ret = zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
+						 virt_to_phys(zdev->dma_table), &status);
+			if (ret)
+				zpci_disable_device(zdev);
 		}
-		pci_rescan_bus(zdev->zbus->bus);
 	}
 out:
+	pci_rescan_bus(zdev->zbus->bus);
 	pci_unlock_rescan_remove();
 	if (kn)
 		sysfs_unbreak_active_protection(kn);
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index dc5f7a156ff5..804fb8f42d61 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -93,7 +93,7 @@  config IOMMU_DEBUGFS
 choice
 	prompt "IOMMU default domain type"
 	depends on IOMMU_API
-	default IOMMU_DEFAULT_DMA_LAZY if X86 || IA64
+	default IOMMU_DEFAULT_DMA_LAZY if X86 || IA64 || S390
 	default IOMMU_DEFAULT_DMA_STRICT
 	help
 	  Choose the type of IOMMU domain used to manage DMA API usage by
@@ -412,6 +412,7 @@  config ARM_SMMU_V3_SVA
 config S390_IOMMU
 	def_bool y if S390 && PCI
 	depends on S390 && PCI
+	select IOMMU_DMA
 	select IOMMU_API
 	help
 	  Support for the IOMMU API for s390 PCI devices.
diff --git a/drivers/iommu/s390-iommu.c b/drivers/iommu/s390-iommu.c
index ed33c6cce083..9fd788d64ac8 100644
--- a/drivers/iommu/s390-iommu.c
+++ b/drivers/iommu/s390-iommu.c
@@ -14,16 +14,300 @@ 
 #include <linux/rcupdate.h>
 #include <asm/pci_dma.h>
 
+#include "dma-iommu.h"
+
 static const struct iommu_ops s390_iommu_ops;
 
+static struct kmem_cache *dma_region_table_cache;
+static struct kmem_cache *dma_page_table_cache;
+
+static u64 s390_iommu_aperture;
+static u32 s390_iommu_aperture_factor = 1;
+
 struct s390_domain {
 	struct iommu_domain	domain;
 	struct list_head	devices;
+	struct zpci_iommu_ctrs	ctrs;
 	unsigned long		*dma_table;
 	spinlock_t		list_lock;
 	struct rcu_head		rcu;
 };
 
+static inline unsigned int calc_rtx(dma_addr_t ptr)
+{
+	return ((unsigned long)ptr >> ZPCI_RT_SHIFT) & ZPCI_INDEX_MASK;
+}
+
+static inline unsigned int calc_sx(dma_addr_t ptr)
+{
+	return ((unsigned long)ptr >> ZPCI_ST_SHIFT) & ZPCI_INDEX_MASK;
+}
+
+static inline unsigned int calc_px(dma_addr_t ptr)
+{
+	return ((unsigned long)ptr >> PAGE_SHIFT) & ZPCI_PT_MASK;
+}
+
+static inline void set_pt_pfaa(unsigned long *entry, phys_addr_t pfaa)
+{
+	*entry &= ZPCI_PTE_FLAG_MASK;
+	*entry |= (pfaa & ZPCI_PTE_ADDR_MASK);
+}
+
+static inline void set_rt_sto(unsigned long *entry, phys_addr_t sto)
+{
+	*entry &= ZPCI_RTE_FLAG_MASK;
+	*entry |= (sto & ZPCI_RTE_ADDR_MASK);
+	*entry |= ZPCI_TABLE_TYPE_RTX;
+}
+
+static inline void set_st_pto(unsigned long *entry, phys_addr_t pto)
+{
+	*entry &= ZPCI_STE_FLAG_MASK;
+	*entry |= (pto & ZPCI_STE_ADDR_MASK);
+	*entry |= ZPCI_TABLE_TYPE_SX;
+}
+
+static inline void validate_rt_entry(unsigned long *entry)
+{
+	*entry &= ~ZPCI_TABLE_VALID_MASK;
+	*entry &= ~ZPCI_TABLE_OFFSET_MASK;
+	*entry |= ZPCI_TABLE_VALID;
+	*entry |= ZPCI_TABLE_LEN_RTX;
+}
+
+static inline void validate_st_entry(unsigned long *entry)
+{
+	*entry &= ~ZPCI_TABLE_VALID_MASK;
+	*entry |= ZPCI_TABLE_VALID;
+}
+
+static inline void invalidate_pt_entry(unsigned long *entry)
+{
+	WARN_ON_ONCE((*entry & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_INVALID);
+	*entry &= ~ZPCI_PTE_VALID_MASK;
+	*entry |= ZPCI_PTE_INVALID;
+}
+
+static inline void validate_pt_entry(unsigned long *entry)
+{
+	WARN_ON_ONCE((*entry & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID);
+	*entry &= ~ZPCI_PTE_VALID_MASK;
+	*entry |= ZPCI_PTE_VALID;
+}
+
+static inline void entry_set_protected(unsigned long *entry)
+{
+	*entry &= ~ZPCI_TABLE_PROT_MASK;
+	*entry |= ZPCI_TABLE_PROTECTED;
+}
+
+static inline void entry_clr_protected(unsigned long *entry)
+{
+	*entry &= ~ZPCI_TABLE_PROT_MASK;
+	*entry |= ZPCI_TABLE_UNPROTECTED;
+}
+
+static inline int reg_entry_isvalid(unsigned long entry)
+{
+	return (entry & ZPCI_TABLE_VALID_MASK) == ZPCI_TABLE_VALID;
+}
+
+static inline int pt_entry_isvalid(unsigned long entry)
+{
+	return (entry & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID;
+}
+
+static inline unsigned long *get_rt_sto(unsigned long entry)
+{
+	if ((entry & ZPCI_TABLE_TYPE_MASK) == ZPCI_TABLE_TYPE_RTX)
+		return phys_to_virt(entry & ZPCI_RTE_ADDR_MASK);
+	else
+		return NULL;
+}
+
+static inline unsigned long *get_st_pto(unsigned long entry)
+{
+	if ((entry & ZPCI_TABLE_TYPE_MASK) == ZPCI_TABLE_TYPE_SX)
+		return phys_to_virt(entry & ZPCI_STE_ADDR_MASK);
+	else
+		return NULL;
+}
+
+static int __init dma_alloc_cpu_table_caches(void)
+{
+	dma_region_table_cache = kmem_cache_create("PCI_DMA_region_tables",
+						   ZPCI_TABLE_SIZE,
+						   ZPCI_TABLE_ALIGN,
+						   0, NULL);
+	if (!dma_region_table_cache)
+		return -ENOMEM;
+
+	dma_page_table_cache = kmem_cache_create("PCI_DMA_page_tables",
+						 ZPCI_PT_SIZE,
+						 ZPCI_PT_ALIGN,
+						 0, NULL);
+	if (!dma_page_table_cache) {
+		kmem_cache_destroy(dma_region_table_cache);
+		return -ENOMEM;
+	}
+	return 0;
+}
+
+static unsigned long *dma_alloc_cpu_table(void)
+{
+	unsigned long *table, *entry;
+
+	table = kmem_cache_alloc(dma_region_table_cache, GFP_ATOMIC);
+	if (!table)
+		return NULL;
+
+	for (entry = table; entry < table + ZPCI_TABLE_ENTRIES; entry++)
+		*entry = ZPCI_TABLE_INVALID;
+	return table;
+}
+
+static void dma_free_cpu_table(void *table)
+{
+	kmem_cache_free(dma_region_table_cache, table);
+}
+
+static void dma_free_page_table(void *table)
+{
+	kmem_cache_free(dma_page_table_cache, table);
+}
+
+static void dma_free_seg_table(unsigned long entry)
+{
+	unsigned long *sto = get_rt_sto(entry);
+	int sx;
+
+	for (sx = 0; sx < ZPCI_TABLE_ENTRIES; sx++)
+		if (reg_entry_isvalid(sto[sx]))
+			dma_free_page_table(get_st_pto(sto[sx]));
+
+	dma_free_cpu_table(sto);
+}
+
+static void dma_cleanup_tables(unsigned long *table)
+{
+	int rtx;
+
+	if (!table)
+		return;
+
+	for (rtx = 0; rtx < ZPCI_TABLE_ENTRIES; rtx++)
+		if (reg_entry_isvalid(table[rtx]))
+			dma_free_seg_table(table[rtx]);
+
+	dma_free_cpu_table(table);
+}
+
+static unsigned long *dma_alloc_page_table(void)
+{
+	unsigned long *table, *entry;
+
+	table = kmem_cache_alloc(dma_page_table_cache, GFP_ATOMIC);
+	if (!table)
+		return NULL;
+
+	for (entry = table; entry < table + ZPCI_PT_ENTRIES; entry++)
+		*entry = ZPCI_PTE_INVALID;
+	return table;
+}
+
+static unsigned long *dma_get_seg_table_origin(unsigned long *rtep)
+{
+	unsigned long old_rte, rte;
+	unsigned long *sto;
+
+	rte = READ_ONCE(*rtep);
+	if (reg_entry_isvalid(rte)) {
+		sto = get_rt_sto(rte);
+	} else {
+		sto = dma_alloc_cpu_table();
+		if (!sto)
+			return NULL;
+
+		set_rt_sto(&rte, virt_to_phys(sto));
+		validate_rt_entry(&rte);
+		entry_clr_protected(&rte);
+
+		old_rte = cmpxchg(rtep, ZPCI_TABLE_INVALID, rte);
+		if (old_rte != ZPCI_TABLE_INVALID) {
+			/* Somone else was faster, use theirs */
+			dma_free_cpu_table(sto);
+			sto = get_rt_sto(old_rte);
+		}
+	}
+	return sto;
+}
+
+static unsigned long *dma_get_page_table_origin(unsigned long *step)
+{
+	unsigned long old_ste, ste;
+	unsigned long *pto;
+
+	ste = READ_ONCE(*step);
+	if (reg_entry_isvalid(ste)) {
+		pto = get_st_pto(ste);
+	} else {
+		pto = dma_alloc_page_table();
+		if (!pto)
+			return NULL;
+		set_st_pto(&ste, virt_to_phys(pto));
+		validate_st_entry(&ste);
+		entry_clr_protected(&ste);
+
+		old_ste = cmpxchg(step, ZPCI_TABLE_INVALID, ste);
+		if (old_ste != ZPCI_TABLE_INVALID) {
+			/* Somone else was faster, use theirs */
+			dma_free_page_table(pto);
+			pto = get_st_pto(old_ste);
+		}
+	}
+	return pto;
+}
+
+static unsigned long *dma_walk_cpu_trans(unsigned long *rto, dma_addr_t dma_addr)
+{
+	unsigned long *sto, *pto;
+	unsigned int rtx, sx, px;
+
+	rtx = calc_rtx(dma_addr);
+	sto = dma_get_seg_table_origin(&rto[rtx]);
+	if (!sto)
+		return NULL;
+
+	sx = calc_sx(dma_addr);
+	pto = dma_get_page_table_origin(&sto[sx]);
+	if (!pto)
+		return NULL;
+
+	px = calc_px(dma_addr);
+	return &pto[px];
+}
+
+static void dma_update_cpu_trans(unsigned long *ptep, phys_addr_t page_addr, int flags)
+{
+	unsigned long pte;
+
+	pte = READ_ONCE(*ptep);
+	if (flags & ZPCI_PTE_INVALID) {
+		invalidate_pt_entry(&pte);
+	} else {
+		set_pt_pfaa(&pte, page_addr);
+		validate_pt_entry(&pte);
+	}
+
+	if (flags & ZPCI_TABLE_PROTECTED)
+		entry_set_protected(&pte);
+	else
+		entry_clr_protected(&pte);
+
+	xchg(ptep, pte);
+}
+
 static struct s390_domain *to_s390_domain(struct iommu_domain *dom)
 {
 	return container_of(dom, struct s390_domain, domain);
@@ -45,9 +329,14 @@  static struct iommu_domain *s390_domain_alloc(unsigned domain_type)
 {
 	struct s390_domain *s390_domain;
 
-	if (domain_type != IOMMU_DOMAIN_UNMANAGED)
+	switch (domain_type) {
+	case IOMMU_DOMAIN_DMA:
+	case IOMMU_DOMAIN_DMA_FQ:
+	case IOMMU_DOMAIN_UNMANAGED:
+		break;
+	default:
 		return NULL;
-
+	}
 	s390_domain = kzalloc(sizeof(*s390_domain), GFP_KERNEL);
 	if (!s390_domain)
 		return NULL;
@@ -86,11 +375,14 @@  static void s390_domain_free(struct iommu_domain *domain)
 	call_rcu(&s390_domain->rcu, s390_iommu_rcu_free_domain);
 }
 
-static void __s390_iommu_detach_device(struct zpci_dev *zdev)
+static void s390_iommu_detach_device(struct iommu_domain *domain,
+				     struct device *dev)
 {
-	struct s390_domain *s390_domain = zdev->s390_domain;
+	struct s390_domain *s390_domain = to_s390_domain(domain);
+	struct zpci_dev *zdev = to_zpci_dev(dev);
 	unsigned long flags;
 
+	WARN_ON(zdev->s390_domain != to_s390_domain(domain));
 	if (!s390_domain)
 		return;
 
@@ -120,9 +412,7 @@  static int s390_iommu_attach_device(struct iommu_domain *domain,
 		return -EINVAL;
 
 	if (zdev->s390_domain)
-		__s390_iommu_detach_device(zdev);
-	else if (zdev->dma_table)
-		zpci_dma_exit_device(zdev);
+		s390_iommu_detach_device(&zdev->s390_domain->domain, dev);
 
 	cc = zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
 				virt_to_phys(s390_domain->dma_table), &status);
@@ -144,17 +434,6 @@  static int s390_iommu_attach_device(struct iommu_domain *domain,
 	return 0;
 }
 
-static void s390_iommu_detach_device(struct iommu_domain *domain,
-				     struct device *dev)
-{
-	struct zpci_dev *zdev = to_zpci_dev(dev);
-
-	WARN_ON(zdev->s390_domain != to_s390_domain(domain));
-
-	__s390_iommu_detach_device(zdev);
-	zpci_dma_init_device(zdev);
-}
-
 static void s390_iommu_get_resv_regions(struct device *dev,
 					struct list_head *list)
 {
@@ -207,7 +486,7 @@  static void s390_iommu_release_device(struct device *dev)
 	 * to the device, but keep it attached to other devices in the group.
 	 */
 	if (zdev)
-		__s390_iommu_detach_device(zdev);
+		s390_iommu_detach_device(&zdev->s390_domain->domain, dev);
 }
 
 static void s390_iommu_flush_iotlb_all(struct iommu_domain *domain)
@@ -217,6 +496,7 @@  static void s390_iommu_flush_iotlb_all(struct iommu_domain *domain)
 
 	rcu_read_lock();
 	list_for_each_entry_rcu(zdev, &s390_domain->devices, iommu_list) {
+		atomic64_inc(&s390_domain->ctrs.global_rpcits);
 		zpci_refresh_trans((u64)zdev->fh << 32, zdev->start_dma,
 				   zdev->end_dma - zdev->start_dma + 1);
 	}
@@ -236,6 +516,7 @@  static void s390_iommu_iotlb_sync(struct iommu_domain *domain,
 
 	rcu_read_lock();
 	list_for_each_entry_rcu(zdev, &s390_domain->devices, iommu_list) {
+		atomic64_inc(&s390_domain->ctrs.sync_rpcits);
 		zpci_refresh_trans((u64)zdev->fh << 32, gather->start,
 				   size);
 	}
@@ -252,6 +533,7 @@  static void s390_iommu_iotlb_sync_map(struct iommu_domain *domain,
 	list_for_each_entry_rcu(zdev, &s390_domain->devices, iommu_list) {
 		if (!zdev->tlb_refresh)
 			continue;
+		atomic64_inc(&s390_domain->ctrs.sync_map_rpcits);
 		zpci_refresh_trans((u64)zdev->fh << 32,
 				   iova, size);
 	}
@@ -332,16 +614,15 @@  static int s390_iommu_map_pages(struct iommu_domain *domain,
 	if (!IS_ALIGNED(iova | paddr, pgsize))
 		return -EINVAL;
 
-	if (!(prot & IOMMU_READ))
-		return -EINVAL;
-
 	if (!(prot & IOMMU_WRITE))
 		flags |= ZPCI_TABLE_PROTECTED;
 
 	rc = s390_iommu_validate_trans(s390_domain, paddr, iova,
-				       pgcount, flags);
-	if (!rc)
+				     pgcount, flags);
+	if (!rc) {
 		*mapped = size;
+		atomic64_add(pgcount, &s390_domain->ctrs.mapped_pages);
+	}
 
 	return rc;
 }
@@ -397,12 +678,29 @@  static size_t s390_iommu_unmap_pages(struct iommu_domain *domain,
 		return 0;
 
 	iommu_iotlb_gather_add_range(gather, iova, size);
+	atomic64_add(pgcount, &s390_domain->ctrs.unmapped_pages);
 
 	return size;
 }
 
+static void s390_iommu_probe_finalize(struct device *dev)
+{
+	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
+
+	iommu_dma_forcedac = true;
+	iommu_setup_dma_ops(dev, domain->geometry.aperture_start, domain->geometry.aperture_end);
+}
+
+struct zpci_iommu_ctrs *zpci_get_iommu_ctrs(struct zpci_dev *zdev)
+{
+	if (!zdev && !zdev->s390_domain)
+		return NULL;
+	return &zdev->s390_domain->ctrs;
+}
+
 int zpci_init_iommu(struct zpci_dev *zdev)
 {
+	u64 aperture_size;
 	int rc = 0;
 
 	rc = iommu_device_sysfs_add(&zdev->iommu_dev, NULL, NULL,
@@ -414,6 +712,12 @@  int zpci_init_iommu(struct zpci_dev *zdev)
 	if (rc)
 		goto out_sysfs;
 
+	zdev->start_dma = PAGE_ALIGN(zdev->start_dma);
+	aperture_size = min3(s390_iommu_aperture,
+			     ZPCI_TABLE_SIZE_RT - zdev->start_dma,
+			     zdev->end_dma - zdev->start_dma + 1);
+	zdev->end_dma = zdev->start_dma + aperture_size - 1;
+
 	return 0;
 
 out_sysfs:
@@ -429,10 +733,49 @@  void zpci_destroy_iommu(struct zpci_dev *zdev)
 	iommu_device_sysfs_remove(&zdev->iommu_dev);
 }
 
+static int __init s390_iommu_setup(char *str)
+{
+	if (!strcmp(str, "strict")) {
+		pr_warn("s390_iommu=strict deprecated; use iommu.strict=1 instead\n");
+		iommu_set_dma_strict();
+	}
+	return 1;
+}
+
+__setup("s390_iommu=", s390_iommu_setup);
+
+static int __init s390_iommu_aperture_setup(char *str)
+{
+	if (kstrtou32(str, 10, &s390_iommu_aperture_factor))
+		s390_iommu_aperture_factor = 1;
+	return 1;
+}
+
+__setup("s390_iommu_aperture=", s390_iommu_aperture_setup);
+
+static int __init s390_iommu_init(void)
+{
+	int rc;
+
+	s390_iommu_aperture = (u64)virt_to_phys(high_memory);
+	if (!s390_iommu_aperture_factor)
+		s390_iommu_aperture = ULONG_MAX;
+	else
+		s390_iommu_aperture *= s390_iommu_aperture_factor;
+
+	rc = dma_alloc_cpu_table_caches();
+	if (rc)
+		return rc;
+
+	return rc;
+}
+subsys_initcall(s390_iommu_init);
+
 static const struct iommu_ops s390_iommu_ops = {
 	.capable = s390_iommu_capable,
 	.domain_alloc = s390_domain_alloc,
 	.probe_device = s390_iommu_probe_device,
+	.probe_finalize = s390_iommu_probe_finalize,
 	.release_device = s390_iommu_release_device,
 	.device_group = generic_device_group,
 	.pgsize_bitmap = SZ_4K,