[PATCH v2 09/11] s390: mm: Convert to GENERIC_IOREMAP

[Baoquan He <bhe@xxxxxxxxxx>]

Add hooks arch_ioremap() and arch_iounmap() for s390's special
operation when ioremap() and iounmap(), then ioremap_[wc|wt]() are
converted to use ioremap_prot() from GENERIC_IOREMAP.

Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
Cc: Heiko Carstens <hca@xxxxxxxxxxxxx>
Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx>
Cc: Alexander Gordeev <agordeev@xxxxxxxxxxxxx>
Cc: Christian Borntraeger <borntraeger@xxxxxxxxxxxxx>
Cc: Sven Schnelle <svens@xxxxxxxxxxxxx>
Cc: linux-s390@xxxxxxxxxxxxxxx
---
 arch/s390/Kconfig          |  1 +
 arch/s390/include/asm/io.h | 26 +++++++++++------
 arch/s390/pci/pci.c        | 60 +++++---------------------------------
 3 files changed, 26 insertions(+), 61 deletions(-)

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 318fce77601d..c59e1b25f59d 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -135,6 +135,7 @@ config S390
 	select GENERIC_SMP_IDLE_THREAD
 	select GENERIC_TIME_VSYSCALL
 	select GENERIC_VDSO_TIME_NS
+	select GENERIC_IOREMAP
 	select HAVE_ALIGNED_STRUCT_PAGE if SLUB
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_ARCH_JUMP_LABEL
diff --git a/arch/s390/include/asm/io.h b/arch/s390/include/asm/io.h
index e3882b012bfa..f837e20b7bbd 100644
--- a/arch/s390/include/asm/io.h
+++ b/arch/s390/include/asm/io.h
@@ -22,11 +22,23 @@ void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr);
 
 #define IO_SPACE_LIMIT 0
 
-void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot);
-void __iomem *ioremap(phys_addr_t addr, size_t size);
-void __iomem *ioremap_wc(phys_addr_t addr, size_t size);
-void __iomem *ioremap_wt(phys_addr_t addr, size_t size);
-void iounmap(volatile void __iomem *addr);
+
+/*
+ * I/O memory mapping functions.
+ */
+void __iomem *
+arch_ioremap(phys_addr_t *paddr, size_t size, unsigned long *prot_val);
+#define arch_ioremap arch_ioremap
+
+int arch_iounmap(void __iomem *addr);
+#define arch_iounmap arch_iounmap
+
+#define _PAGE_IOREMAP pgprot_val(PAGE_KERNEL)
+
+#define ioremap_wc(addr, size)  \
+	ioremap_prot((addr), (size), pgprot_val(pgprot_writecombine(PAGE_KERNEL)))
+#define ioremap_wt(addr, size)  \
+	ioremap_prot((addr), (size), pgprot_val(pgprot_writethrough(PAGE_KERNEL)))
 
 static inline void __iomem *ioport_map(unsigned long port, unsigned int nr)
 {
@@ -51,10 +63,6 @@ static inline void ioport_unmap(void __iomem *p)
 #define pci_iomap_wc pci_iomap_wc
 #define pci_iomap_wc_range pci_iomap_wc_range
 
-#define ioremap ioremap
-#define ioremap_wt ioremap_wt
-#define ioremap_wc ioremap_wc
-
 #define memcpy_fromio(dst, src, count)	zpci_memcpy_fromio(dst, src, count)
 #define memcpy_toio(dst, src, count)	zpci_memcpy_toio(dst, src, count)
 #define memset_io(dst, val, count)	zpci_memset_io(dst, val, count)
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index 73cdc5539384..984cad9cd5a1 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -244,64 +244,20 @@ void __iowrite64_copy(void __iomem *to, const void *from, size_t count)
        zpci_memcpy_toio(to, from, count);
 }
 
-static void __iomem *__ioremap(phys_addr_t addr, size_t size, pgprot_t prot)
+void __iomem *
+arch_ioremap(phys_addr_t *paddr, size_t size, unsigned long *prot_val)
 {
-	unsigned long offset, vaddr;
-	struct vm_struct *area;
-	phys_addr_t last_addr;
-
-	last_addr = addr + size - 1;
-	if (!size || last_addr < addr)
-		return NULL;
-
 	if (!static_branch_unlikely(&have_mio))
-		return (void __iomem *) addr;
-
-	offset = addr & ~PAGE_MASK;
-	addr &= PAGE_MASK;
-	size = PAGE_ALIGN(size + offset);
-	area = get_vm_area(size, VM_IOREMAP);
-	if (!area)
-		return NULL;
-
-	vaddr = (unsigned long) area->addr;
-	if (ioremap_page_range(vaddr, vaddr + size, addr, prot)) {
-		free_vm_area(area);
-		return NULL;
-	}
-	return (void __iomem *) ((unsigned long) area->addr + offset);
-}
-
-void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot)
-{
-	return __ioremap(addr, size, __pgprot(prot));
+		return (void __iomem *) *paddr;
+	return NULL;
 }
-EXPORT_SYMBOL(ioremap_prot);
 
-void __iomem *ioremap(phys_addr_t addr, size_t size)
+int arch_iounmap(void __iomem *addr)
 {
-	return __ioremap(addr, size, PAGE_KERNEL);
-}
-EXPORT_SYMBOL(ioremap);
-
-void __iomem *ioremap_wc(phys_addr_t addr, size_t size)
-{
-	return __ioremap(addr, size, pgprot_writecombine(PAGE_KERNEL));
-}
-EXPORT_SYMBOL(ioremap_wc);
-
-void __iomem *ioremap_wt(phys_addr_t addr, size_t size)
-{
-	return __ioremap(addr, size, pgprot_writethrough(PAGE_KERNEL));
-}
-EXPORT_SYMBOL(ioremap_wt);
-
-void iounmap(volatile void __iomem *addr)
-{
-	if (static_branch_likely(&have_mio))
-		vunmap((__force void *) ((unsigned long) addr & PAGE_MASK));
+	if (!static_branch_likely(&have_mio))
+		return -EINVAL;
+	return 0;
 }
-EXPORT_SYMBOL(iounmap);
 
 /* Create a virtual mapping cookie for a PCI BAR */
 static void __iomem *pci_iomap_range_fh(struct pci_dev *pdev, int bar,
-- 
2.34.1