[<prev] [next>] [day] [month] [year] [list]
Message-Id: <1548851629-9408-1-git-send-email-guoren@kernel.org>
Date: Wed, 30 Jan 2019 20:33:49 +0800
From: guoren@...nel.org
To: arnd@...db.de
Cc: linux-kernel@...r.kernel.org, guoren@...nel.org,
linux-arch@...r.kernel.org, xiaodong.fan@...ahualu.com,
Guo Ren <ren_guo@...ky.com>
Subject: [PATCH] csky: Fixup io-range page attribute for mmap("/dev/mem")
From: Guo Ren <ren_guo@...ky.com>
Some user space drivers need accessing IO address and IO remap need
SO(strong order) page-attribute to make IO operation correct. So we
need add SO-page-attr for all non-memory address.
Signed-off-by: Guo Ren <ren_guo@...ky.com>
Reported-by: Fan Xiaodong <xiaodong.fan@...ahualu.com>
---
arch/csky/include/asm/pgtable.h | 5 +++++
arch/csky/mm/ioremap.c | 14 ++++++++++++++
2 files changed, 19 insertions(+)
diff --git a/arch/csky/include/asm/pgtable.h b/arch/csky/include/asm/pgtable.h
index af7a7fa..dcea277 100644
--- a/arch/csky/include/asm/pgtable.h
+++ b/arch/csky/include/asm/pgtable.h
@@ -241,6 +241,11 @@ static inline pte_t pte_mkyoung(pte_t pte)
#define pgd_index(address) ((address) >> PGDIR_SHIFT)
+#define __HAVE_PHYS_MEM_ACCESS_PROT
+struct file;
+extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
+ unsigned long size, pgprot_t vma_prot);
+
/*
* Macro to make mark a page protection value as "uncacheable". Note
* that "protection" is really a misnomer here as the protection value
diff --git a/arch/csky/mm/ioremap.c b/arch/csky/mm/ioremap.c
index cb7c03e..8473b6b 100644
--- a/arch/csky/mm/ioremap.c
+++ b/arch/csky/mm/ioremap.c
@@ -46,3 +46,17 @@ void iounmap(void __iomem *addr)
vunmap((void *)((unsigned long)addr & PAGE_MASK));
}
EXPORT_SYMBOL(iounmap);
+
+pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
+ unsigned long size, pgprot_t vma_prot)
+{
+ if (!pfn_valid(pfn)) {
+ vma_prot.pgprot |= _PAGE_SO;
+ return pgprot_noncached(vma_prot);
+ } else if (file->f_flags & O_SYNC) {
+ return pgprot_noncached(vma_prot);
+ }
+
+ return vma_prot;
+}
+EXPORT_SYMBOL(phys_mem_access_prot);
--
2.7.4
Powered by blists - more mailing lists