[PATCH v7 12/19] sh: mm: Convert to GENERIC_IOREMAP

Baoquan He
2023-06-20T13:19:20Z

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 SuperH's
special operation when ioremap() and iounmap().

Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: linux-sh@vger.kernel.org
---
arch/sh/Kconfig | 1 +
arch/sh/include/asm/io.h | 40 +++++--------------------
arch/sh/mm/ioremap.c | 65 +++++++---------------------------------
3 files changed, 20 insertions(+), 86 deletions(-)

diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 9652d367fc37..f326985e46e0 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -28,6 +28,7 @@ config SUPERH
select GENERIC_SMP_IDLE_THREAD
select GUP_GET_PXX_LOW_HIGH if X2TLB
select HAS_IOPORT if HAS_IOPORT_MAP
+ select GENERIC_IOREMAP if MMU
select HAVE_ARCH_AUDITSYSCALL
select HAVE_ARCH_KGDB
select HAVE_ARCH_SECCOMP_FILTER
diff --git a/arch/sh/include/asm/io.h b/arch/sh/include/asm/io.h
index 270e7952950c..b3a26b405c8d 100644
--- a/arch/sh/include/asm/io.h
+++ b/arch/sh/include/asm/io.h
@@ -266,40 +266,16 @@ unsigned long long poke_real_address_q(unsigned long long addr,
#endif

#ifdef CONFIG_MMU
-void iounmap(void __iomem *addr);
-void __iomem *__ioremap_caller(phys_addr_t offset, unsigned long size,
- pgprot_t prot, void *caller);
-
-static inline void __iomem *ioremap(phys_addr_t offset, unsigned long size)
-{
- return __ioremap_caller(offset, size, PAGE_KERNEL_NOCACHE,
- __builtin_return_address(0));
-}
-
-static inline void __iomem *
-ioremap_cache(phys_addr_t offset, unsigned long size)
-{
- return __ioremap_caller(offset, size, PAGE_KERNEL,
- __builtin_return_address(0));
-}
-#define ioremap_cache ioremap_cache
-
-#ifdef CONFIG_HAVE_IOREMAP_PROT
-static inline void __iomem *ioremap_prot(phys_addr_t offset, unsigned long size,
- unsigned long flags)
-{
- return __ioremap_caller(offset, size, __pgprot(flags),
- __builtin_return_address(0));
-}
-#endif /* CONFIG_HAVE_IOREMAP_PROT */
+/*
+ * I/O memory mapping functions.
+ */
+#define ioremap_prot ioremap_prot
+#define iounmap iounmap

-#else /* CONFIG_MMU */
-static inline void __iomem *ioremap(phys_addr_t offset, size_t size)
-{
- return (void __iomem *)(unsigned long)offset;
-}
+#define _PAGE_IOREMAP pgprot_val(PAGE_KERNEL_NOCACHE)

-static inline void iounmap(volatile void __iomem *addr) { }
+#define ioremap_cache(addr, size) \
+ ioremap_prot((addr), (size), pgprot_val(PAGE_KERNEL))
#endif /* CONFIG_MMU */

#define ioremap_uc ioremap
diff --git a/arch/sh/mm/ioremap.c b/arch/sh/mm/ioremap.c
index 21342581144d..c33b3daa4ad1 100644
--- a/arch/sh/mm/ioremap.c
+++ b/arch/sh/mm/ioremap.c
@@ -72,22 +72,11 @@ __ioremap_29bit(phys_addr_t offset, unsigned long size, pgprot_t prot)
#define __ioremap_29bit(offset, size, prot) NULL
#endif /* CONFIG_29BIT */

-/*
- * Remap an arbitrary physical address space into the kernel virtual
- * address space. Needed when the kernel wants to access high addresses
- * directly.
- *
- * NOTE! We need to allow non-page-aligned mappings too: we will obviously
- * have to convert them into an offset in a page-aligned mapping, but the
- * caller shouldn't need to know that small detail.
- */
-void __iomem * __ref
-__ioremap_caller(phys_addr_t phys_addr, unsigned long size,
- pgprot_t pgprot, void *caller)
+void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size,
+ unsigned long prot)
{
- struct vm_struct *area;
- unsigned long offset, last_addr, addr, orig_addr;
void __iomem *mapped;
+ pgprot_t pgprot = __pgprot(prot);

mapped = __ioremap_trapped(phys_addr, size);
if (mapped)
@@ -97,11 +86,6 @@ __ioremap_caller(phys_addr_t phys_addr, unsigned long size,
if (mapped)
return mapped;

- /* Don't allow wraparound or zero size */
- last_addr = phys_addr + size - 1;
- if (!size || last_addr < phys_addr)
- return NULL;
-
/*
* If we can't yet use the regular approach, go the fixmap route.
*/
@@ -112,34 +96,14 @@ __ioremap_caller(phys_addr_t phys_addr, unsigned long size,
* First try to remap through the PMB.
* PMB entries are all pre-faulted.
*/
- mapped = pmb_remap_caller(phys_addr, size, pgprot, caller);
+ mapped = pmb_remap_caller(phys_addr, size, pgprot,
+ __builtin_return_address(0));
if (mapped && !IS_ERR(mapped))
return mapped;

- /*
- * Mappings have to be page-aligned
- */
- offset = phys_addr & ~PAGE_MASK;
- phys_addr &= PAGE_MASK;
- size = PAGE_ALIGN(last_addr+1) - phys_addr;
-
- /*
- * Ok, go for it..
- */
- area = get_vm_area_caller(size, VM_IOREMAP, caller);
- if (!area)
- return NULL;
- area->phys_addr = phys_addr;
- orig_addr = addr = (unsigned long)area->addr;
-
- if (ioremap_page_range(addr, addr + size, phys_addr, pgprot)) {
- vunmap((void *)orig_addr);
- return NULL;
- }
-
- return (void __iomem *)(offset + (char *)orig_addr);
+ return generic_ioremap_prot(phys_addr, size, pgprot);
}
-EXPORT_SYMBOL(__ioremap_caller);
+EXPORT_SYMBOL(ioremap_prot);

/*
* Simple checks for non-translatable mappings.
@@ -158,10 +122,9 @@ static inline int iomapping_nontranslatable(unsigned long offset)
return 0;
}

-void iounmap(void __iomem *addr)
+void iounmap(volatile void __iomem *addr)
{
unsigned long vaddr = (unsigned long __force)addr;
- struct vm_struct *p;

/*
* Nothing to do if there is no translatable mapping.
@@ -172,21 +135,15 @@ void iounmap(void __iomem *addr)
/*
* There's no VMA if it's from an early fixed mapping.
*/
- if (iounmap_fixed(addr) == 0)
+ if (iounmap_fixed((void __iomem *)addr) == 0)
return;

/*
* If the PMB handled it, there's nothing else to do.
*/
- if (pmb_unmap(addr) == 0)
+ if (pmb_unmap((void __iomem *)addr) == 0)
return;

- p = remove_vm_area((void *)(vaddr & PAGE_MASK));
- if (!p) {
- printk(KERN_ERR "%s: bad address %p\n", __func__, addr);
- return;
- }
-
- kfree(p);
+ generic_iounmap(addr);
}
EXPORT_SYMBOL(iounmap);
--
2.34.1