[PATCH v10 4/6] s390/pci: Use dma-iommu layer

From: Niklas Schnelle
Date: Wed May 24 2023 - 10:56:24 EST

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.

Reviewed-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>
Signed-off-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx>
---
Documentation/admin-guide/kernel-parameters.txt | 9 +-
arch/s390/include/asm/pci.h | 7 -
arch/s390/include/asm/pci_clp.h | 3 +
arch/s390/include/asm/pci_dma.h | 119 +---
arch/s390/pci/Makefile | 2 +-
arch/s390/pci/pci.c | 22 +-
arch/s390/pci/pci_bus.c | 5 -
arch/s390/pci/pci_debug.c | 12 +-
arch/s390/pci/pci_dma.c | 735 ------------------------
arch/s390/pci/pci_event.c | 2 -
arch/s390/pci/pci_sysfs.c | 19 +-
drivers/iommu/Kconfig | 4 +-
drivers/iommu/s390-iommu.c | 390 ++++++++++++-
13 files changed, 406 insertions(+), 923 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 9e5bab29685f..8094987c528e 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2182,7 +2182,7 @@
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
@@ -5477,9 +5477,10 @@
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_clp.h b/arch/s390/include/asm/pci_clp.h
index d6189ed14f84..f0c677ddd270 100644
--- a/arch/s390/include/asm/pci_clp.h
+++ b/arch/s390/include/asm/pci_clp.h
@@ -50,6 +50,9 @@ struct clp_fh_list_entry {
#define CLP_UTIL_STR_LEN 64
#define CLP_PFIP_NR_SEGMENTS 4

+/* PCI function type numbers */
+#define PCI_FUNC_TYPE_ISM 0x5 /* ISM device */
+
extern bool zpci_unique_uid;

struct clp_rsp_slpc_pci {
diff --git a/arch/s390/include/asm/pci_dma.h b/arch/s390/include/asm/pci_dma.h
index 7119c04c51c5..42d7cc4262ca 100644
--- a/arch/s390/include/asm/pci_dma.h
+++ b/arch/s390/include/asm/pci_dma.h
@@ -82,117 +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;
-}
+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;
+};

-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(gfp_t gfp);
-void dma_cleanup_tables(unsigned long *);
-unsigned long *dma_walk_cpu_trans(unsigned long *rto, dma_addr_t dma_addr,
- gfp_t gfp);
-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_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 afc3f33788da..36aea977bbe0 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 == PCI_FUNC_TYPE_ISM && 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);
@@ -619,7 +623,6 @@ 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++) {
@@ -793,8 +796,6 @@ 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;
@@ -902,11 +903,6 @@ 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)
@@ -955,8 +951,6 @@ 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);

@@ -1146,10 +1140,6 @@ 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;
@@ -1159,8 +1149,6 @@ 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 32245b970a0c..daa5d7450c7d 100644
--- a/arch/s390/pci/pci_bus.c
+++ b/arch/s390/pci/pci_bus.c
@@ -47,11 +47,6 @@ 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..6dde2263c79d 100644
--- a/arch/s390/pci/pci_debug.c
+++ b/arch/s390/pci/pci_debug.c
@@ -53,9 +53,11 @@ static char *pci_fmt3_names[] = {
};

static char *pci_sw_names[] = {
- "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 +71,14 @@ 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 2d9b01d7ca4c..000000000000
--- a/arch/s390/pci/pci_dma.c
+++ /dev/null
@@ -1,735 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright IBM Corp. 2012
- *
- * Author(s):
- * Jan Glauber <jang@xxxxxxxxxxxxxxxxxx>
- */
-
-#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(gfp_t gfp)
-{
- unsigned long *table, *entry;
-
- table = kmem_cache_alloc(dma_region_table_cache, gfp);
- 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(gfp_t gfp)
-{
- unsigned long *table, *entry;
-
- table = kmem_cache_alloc(dma_page_table_cache, gfp);
- 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, gfp_t gfp)
-{
- 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(gfp);
- 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, gfp_t gfp)
-{
- 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(gfp);
- 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,
- gfp_t gfp)
-{
- unsigned long *sto, *pto;
- unsigned int rtx, sx, px;
-
- rtx = calc_rtx(dma_addr);
- sto = dma_get_seg_table_origin(&rto[rtx], gfp);
- if (!sto)
- return NULL;
-
- sx = calc_sx(dma_addr);
- pto = dma_get_page_table_origin(&sto[sx], gfp);
- 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,
- GFP_ATOMIC);
- 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,
- GFP_ATOMIC);
- 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(GFP_KERNEL);
- 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 6de900776e24..e35649fe7685 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -91,7 +91,7 @@ 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
@@ -146,7 +146,7 @@ config OF_IOMMU

# IOMMU-agnostic DMA-mapping layer
config IOMMU_DMA
- def_bool ARM64 || IA64 || X86
+ def_bool ARM64 || IA64 || X86 || S390
select DMA_OPS
select IOMMU_API
select IOMMU_IOVA
diff --git a/drivers/iommu/s390-iommu.c b/drivers/iommu/s390-iommu.c
index 6723d77489e8..71b177910eec 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(gfp_t gfp)
+{
+ unsigned long *table, *entry;
+
+ table = kmem_cache_alloc(dma_region_table_cache, gfp);
+ 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(gfp_t gfp)
+{
+ unsigned long *table, *entry;
+
+ table = kmem_cache_alloc(dma_page_table_cache, gfp);
+ 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, gfp_t gfp)
+{
+ 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(gfp);
+ 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, gfp_t gfp)
+{
+ 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(gfp);
+ 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, gfp_t gfp)
+{
+ unsigned long *sto, *pto;
+ unsigned int rtx, sx, px;
+
+ rtx = calc_rtx(dma_addr);
+ sto = dma_get_seg_table_origin(&rto[rtx], gfp);
+ if (!sto)
+ return NULL;
+
+ sx = calc_sx(dma_addr);
+ pto = dma_get_page_table_origin(&sto[sx], gfp);
+ 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);
@@ -43,9 +327,14 @@ 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;
@@ -84,14 +373,13 @@ 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;

- if (!s390_domain)
- return;
-
spin_lock_irqsave(&s390_domain->list_lock, flags);
list_del_rcu(&zdev->iommu_list);
spin_unlock_irqrestore(&s390_domain->list_lock, flags);
@@ -118,9 +406,7 @@ 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);
@@ -130,7 +416,6 @@ static int s390_iommu_attach_device(struct iommu_domain *domain,
*/
if (cc && status != ZPCI_PCI_ST_FUNC_NOT_AVAIL)
return -EIO;
- zdev->dma_table = s390_domain->dma_table;

zdev->dma_table = s390_domain->dma_table;
zdev->s390_domain = s390_domain;
@@ -142,14 +427,6 @@ static int s390_iommu_attach_device(struct iommu_domain *domain,
return 0;
}

-static void s390_iommu_set_platform_dma(struct device *dev)
-{
- struct zpci_dev *zdev = to_zpci_dev(dev);
-
- __s390_iommu_detach_device(zdev);
- zpci_dma_init_device(zdev);
-}
-
static void s390_iommu_get_resv_regions(struct device *dev,
struct list_head *list)
{
@@ -202,7 +479,7 @@ 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 int zpci_refresh_all(struct zpci_dev *zdev)
@@ -218,6 +495,7 @@ 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_all(zdev);
}
rcu_read_unlock();
@@ -236,6 +514,7 @@ 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);
}
@@ -253,6 +532,7 @@ static int 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);
ret = zpci_refresh_trans((u64)zdev->fh << 32,
iova, size);
/*
@@ -347,16 +627,15 @@ 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, gfp);
- if (!rc)
+ pgcount, flags, gfp);
+ if (!rc) {
*mapped = size;
+ atomic64_add(pgcount, &s390_domain->ctrs.mapped_pages);
+ }

return rc;
}
@@ -412,12 +691,27 @@ 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)
+{
+ iommu_dma_forcedac = true;
+ iommu_setup_dma_ops(dev, 0, U64_MAX);
+}
+
+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,
@@ -429,6 +723,12 @@ 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:
@@ -444,13 +744,51 @@ 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,
- .set_platform_dma_ops = s390_iommu_set_platform_dma,
.pgsize_bitmap = SZ_4K,
.get_resv_regions = s390_iommu_get_resv_regions,
.default_domain_ops = &(const struct iommu_domain_ops) {

--
2.39.2