[PATCH 1/2 V2] Add a function(ioremap_encrypted) for kdump when AMD sme enabled.

From: Lianbo Jiang
Date: Thu Jun 14 2018 - 04:48:12 EST


It is convenient to remap the old memory encrypted to the second kernel
by calling ioremap_encrypted().

Signed-off-by: Lianbo Jiang <lijiang@xxxxxxxxxx>
---
Some changes based on V1:
1. remove the sme_active() check in __ioremap_caller().

arch/x86/include/asm/io.h | 3 +++
arch/x86/mm/ioremap.c | 24 ++++++++++++++++--------
2 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
index f6e5b93..989d60b 100644
--- a/arch/x86/include/asm/io.h
+++ b/arch/x86/include/asm/io.h
@@ -192,6 +192,9 @@ extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size);
#define ioremap_cache ioremap_cache
extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size, unsigned long prot_val);
#define ioremap_prot ioremap_prot
+extern void __iomem *ioremap_encrypted(resource_size_t phys_addr,
+ unsigned long size);
+#define ioremap_encrypted ioremap_encrypted

/**
* ioremap - map bus memory into CPU space
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index c63a545..24e0920 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -131,7 +131,8 @@ static void __ioremap_check_mem(resource_size_t addr, unsigned long size,
* caller shouldn't need to know that small detail.
*/
static void __iomem *__ioremap_caller(resource_size_t phys_addr,
- unsigned long size, enum page_cache_mode pcm, void *caller)
+ unsigned long size, enum page_cache_mode pcm,
+ void *caller, bool encrypted)
{
unsigned long offset, vaddr;
resource_size_t last_addr;
@@ -199,7 +200,7 @@ static void __iomem *__ioremap_caller(resource_size_t phys_addr,
* resulting mapping.
*/
prot = PAGE_KERNEL_IO;
- if (sev_active() && mem_flags.desc_other)
+ if ((sev_active() && mem_flags.desc_other) || encrypted)
prot = pgprot_encrypted(prot);

switch (pcm) {
@@ -291,7 +292,7 @@ void __iomem *ioremap_nocache(resource_size_t phys_addr, unsigned long size)
enum page_cache_mode pcm = _PAGE_CACHE_MODE_UC_MINUS;

return __ioremap_caller(phys_addr, size, pcm,
- __builtin_return_address(0));
+ __builtin_return_address(0), false);
}
EXPORT_SYMBOL(ioremap_nocache);

@@ -324,7 +325,7 @@ void __iomem *ioremap_uc(resource_size_t phys_addr, unsigned long size)
enum page_cache_mode pcm = _PAGE_CACHE_MODE_UC;

return __ioremap_caller(phys_addr, size, pcm,
- __builtin_return_address(0));
+ __builtin_return_address(0), false);
}
EXPORT_SYMBOL_GPL(ioremap_uc);

@@ -341,7 +342,7 @@ EXPORT_SYMBOL_GPL(ioremap_uc);
void __iomem *ioremap_wc(resource_size_t phys_addr, unsigned long size)
{
return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WC,
- __builtin_return_address(0));
+ __builtin_return_address(0), false);
}
EXPORT_SYMBOL(ioremap_wc);

@@ -358,14 +359,21 @@ EXPORT_SYMBOL(ioremap_wc);
void __iomem *ioremap_wt(resource_size_t phys_addr, unsigned long size)
{
return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WT,
- __builtin_return_address(0));
+ __builtin_return_address(0), false);
}
EXPORT_SYMBOL(ioremap_wt);

+void __iomem *ioremap_encrypted(resource_size_t phys_addr, unsigned long size)
+{
+ return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WB,
+ __builtin_return_address(0), true);
+}
+EXPORT_SYMBOL(ioremap_encrypted);
+
void __iomem *ioremap_cache(resource_size_t phys_addr, unsigned long size)
{
return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WB,
- __builtin_return_address(0));
+ __builtin_return_address(0), false);
}
EXPORT_SYMBOL(ioremap_cache);

@@ -374,7 +382,7 @@ void __iomem *ioremap_prot(resource_size_t phys_addr, unsigned long size,
{
return __ioremap_caller(phys_addr, size,
pgprot2cachemode(__pgprot(prot_val)),
- __builtin_return_address(0));
+ __builtin_return_address(0), false);
}
EXPORT_SYMBOL(ioremap_prot);

--
2.9.5