[PATCH v5 RESEND 10/17] s390: mm: Convert to GENERIC_IOREMAP

Baoquan He
2023-05-15T09:12:25Z

By taking GENERIC_IOREMAP method, the generic generic_ioremap_prot(),
generic_iounmap(), and their generic wrapper ioremap_prot(), ioremap()
and iounmap() are all visible and available to arch. Arch needs to
provide wrapper functions to override the generic versions if there's
arch specific handling in its ioremap_prot(), ioremap() or iounmap().
This change will simplify implementation by removing duplicated codes
with generic_ioremap_prot() and generic_iounmap(), and has the equivalent
functioality as before.

Here, add wrapper functions ioremap_prot() and iounmap() for s390's
special operation when ioremap() and iounmap().

Signed-off-by: Baoquan He <bhe@redhat.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Tested-by: Niklas Schnelle <schnelle@linux.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: linux-s390@vger.kernel.org
---
arch/s390/Kconfig | 1 +
arch/s390/include/asm/io.h | 21 ++++++++------
arch/s390/pci/pci.c | 57 +++++++-------------------------------
3 files changed, 23 insertions(+), 56 deletions(-)

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index db20c1589a98..f33923fa8c99 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -142,6 +142,7 @@ config S390
select GENERIC_SMP_IDLE_THREAD
select GENERIC_TIME_VSYSCALL
select GENERIC_VDSO_TIME_NS
+ select GENERIC_IOREMAP if PCI
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..4453ad7c11ac 100644
--- a/arch/s390/include/asm/io.h
+++ b/arch/s390/include/asm/io.h
@@ -22,11 +22,18 @@ 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.
+ */
+#define ioremap_prot ioremap_prot
+#define iounmap 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 +58,6 @@ 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 afc3f33788da..d34d5813d006 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -244,62 +244,25 @@ 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 *ioremap_prot(phys_addr_t phys_addr, size_t size,
+ unsigned long prot)
{
- 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;
-
+ /*
+ * When PCI MIO instructions are unavailable the "physical" address
+ * encodes a hint for accessing the PCI memory space it represents.
+ * Just pass it unchanged such that ioread/iowrite can decode it.
+ */
if (!static_branch_unlikely(&have_mio))
- return (void __iomem *) addr;
+ return (void __iomem *)phys_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 generic_ioremap_prot(phys_addr, size, __pgprot(prot));
}
EXPORT_SYMBOL(ioremap_prot);

-void __iomem *ioremap(phys_addr_t addr, size_t size)
-{
- 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));
+ generic_iounmap(addr);
}
EXPORT_SYMBOL(iounmap);

--
2.34.1