linux_dsm_epyc7002/include/linux/io.h
Tom Lendacky 8f716c9b5f x86/mm: Add support to access boot related data in the clear
Boot data (such as EFI related data) is not encrypted when the system is
booted because UEFI/BIOS does not run with SME active. In order to access
this data properly it needs to be mapped decrypted.

Update early_memremap() to provide an arch specific routine to modify the
pagetable protection attributes before they are applied to the new
mapping. This is used to remove the encryption mask for boot related data.

Update memremap() to provide an arch specific routine to determine if RAM
remapping is allowed.  RAM remapping will cause an encrypted mapping to be
generated. By preventing RAM remapping, ioremap_cache() will be used
instead, which will provide a decrypted mapping of the boot related data.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Toshimitsu Kani <toshi.kani@hpe.com>
Cc: kasan-dev@googlegroups.com
Cc: kvm@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/81fb6b4117a5df6b9f2eda342f81bbef4b23d2e5.1500319216.git.thomas.lendacky@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18 11:38:02 +02:00

190 lines
5.8 KiB
C

/*
* Copyright 2006 PathScale, Inc. All Rights Reserved.
*
* This file is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#ifndef _LINUX_IO_H
#define _LINUX_IO_H
#include <linux/types.h>
#include <linux/init.h>
#include <linux/bug.h>
#include <linux/err.h>
#include <asm/io.h>
#include <asm/page.h>
struct device;
struct resource;
__visible void __iowrite32_copy(void __iomem *to, const void *from, size_t count);
void __ioread32_copy(void *to, const void __iomem *from, size_t count);
void __iowrite64_copy(void __iomem *to, const void *from, size_t count);
#ifdef CONFIG_MMU
int ioremap_page_range(unsigned long addr, unsigned long end,
phys_addr_t phys_addr, pgprot_t prot);
#else
static inline int ioremap_page_range(unsigned long addr, unsigned long end,
phys_addr_t phys_addr, pgprot_t prot)
{
return 0;
}
#endif
#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
void __init ioremap_huge_init(void);
int arch_ioremap_pud_supported(void);
int arch_ioremap_pmd_supported(void);
#else
static inline void ioremap_huge_init(void) { }
#endif
/*
* Managed iomap interface
*/
#ifdef CONFIG_HAS_IOPORT_MAP
void __iomem * devm_ioport_map(struct device *dev, unsigned long port,
unsigned int nr);
void devm_ioport_unmap(struct device *dev, void __iomem *addr);
#else
static inline void __iomem *devm_ioport_map(struct device *dev,
unsigned long port,
unsigned int nr)
{
return NULL;
}
static inline void devm_ioport_unmap(struct device *dev, void __iomem *addr)
{
}
#endif
#define IOMEM_ERR_PTR(err) (__force void __iomem *)ERR_PTR(err)
void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
resource_size_t size);
void __iomem *devm_ioremap_nocache(struct device *dev, resource_size_t offset,
resource_size_t size);
void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
resource_size_t size);
void devm_iounmap(struct device *dev, void __iomem *addr);
int check_signature(const volatile void __iomem *io_addr,
const unsigned char *signature, int length);
void devm_ioremap_release(struct device *dev, void *res);
void *devm_memremap(struct device *dev, resource_size_t offset,
size_t size, unsigned long flags);
void devm_memunmap(struct device *dev, void *addr);
void *__devm_memremap_pages(struct device *dev, struct resource *res);
#ifdef CONFIG_PCI
/*
* The PCI specifications (Rev 3.0, 3.2.5 "Transaction Ordering and
* Posting") mandate non-posted configuration transactions. There is
* no ioremap API in the kernel that can guarantee non-posted write
* semantics across arches so provide a default implementation for
* mapping PCI config space that defaults to ioremap_nocache(); arches
* should override it if they have memory mapping implementations that
* guarantee non-posted writes semantics to make the memory mapping
* compliant with the PCI specification.
*/
#ifndef pci_remap_cfgspace
#define pci_remap_cfgspace pci_remap_cfgspace
static inline void __iomem *pci_remap_cfgspace(phys_addr_t offset,
size_t size)
{
return ioremap_nocache(offset, size);
}
#endif
#endif
/*
* Some systems do not have legacy ISA devices.
* /dev/port is not a valid interface on these systems.
* So for those archs, <asm/io.h> should define the following symbol.
*/
#ifndef arch_has_dev_port
#define arch_has_dev_port() (1)
#endif
/*
* Some systems (x86 without PAT) have a somewhat reliable way to mark a
* physical address range such that uncached mappings will actually
* end up write-combining. This facility should be used in conjunction
* with pgprot_writecombine, ioremap-wc, or set_memory_wc, since it has
* no effect if the per-page mechanisms are functional.
* (On x86 without PAT, these functions manipulate MTRRs.)
*
* arch_phys_del_wc(0) or arch_phys_del_wc(any error code) is guaranteed
* to have no effect.
*/
#ifndef arch_phys_wc_add
static inline int __must_check arch_phys_wc_add(unsigned long base,
unsigned long size)
{
return 0; /* It worked (i.e. did nothing). */
}
static inline void arch_phys_wc_del(int handle)
{
}
#define arch_phys_wc_add arch_phys_wc_add
#ifndef arch_phys_wc_index
static inline int arch_phys_wc_index(int handle)
{
return -1;
}
#define arch_phys_wc_index arch_phys_wc_index
#endif
#endif
enum {
/* See memremap() kernel-doc for usage description... */
MEMREMAP_WB = 1 << 0,
MEMREMAP_WT = 1 << 1,
MEMREMAP_WC = 1 << 2,
MEMREMAP_ENC = 1 << 3,
MEMREMAP_DEC = 1 << 4,
};
void *memremap(resource_size_t offset, size_t size, unsigned long flags);
void memunmap(void *addr);
/*
* On x86 PAT systems we have memory tracking that keeps track of
* the allowed mappings on memory ranges. This tracking works for
* all the in-kernel mapping APIs (ioremap*), but where the user
* wishes to map a range from a physical device into user memory
* the tracking won't be updated. This API is to be used by
* drivers which remap physical device pages into userspace,
* and wants to make sure they are mapped WC and not UC.
*/
#ifndef arch_io_reserve_memtype_wc
static inline int arch_io_reserve_memtype_wc(resource_size_t base,
resource_size_t size)
{
return 0;
}
static inline void arch_io_free_memtype_wc(resource_size_t base,
resource_size_t size)
{
}
#endif
#endif /* _LINUX_IO_H */