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author | David Vrabel <david.vrabel@citrix.com> | 2014-01-07 17:03:06 (GMT) |
---|---|---|
committer | Stefano Stabellini <stefano.stabellini@eu.citrix.com> | 2014-09-23 13:36:20 (GMT) |
commit | f955371ca9d3986bca100666041fcfa9b6d21962 (patch) | |
tree | 37433b98ce1cecf3865a398479b148a5ebfc2e9d | |
parent | 7f2f88224517cdaad68b772b2a2095b87dc72886 (diff) | |
download | linux-f955371ca9d3986bca100666041fcfa9b6d21962.tar.xz |
x86: remove the Xen-specific _PAGE_IOMAP PTE flag
The _PAGE_IO_MAP PTE flag was only used by Xen PV guests to mark PTEs
that were used to map I/O regions that are 1:1 in the p2m. This
allowed Xen to obtain the correct PFN when converting the MFNs read
from a PTE back to their PFN.
Xen guests no longer use _PAGE_IOMAP for this. Instead mfn_to_pfn()
returns the correct PFN by using a combination of the m2p and p2m to
determine if an MFN corresponds to a 1:1 mapping in the the p2m.
Remove _PAGE_IOMAP, replacing it with _PAGE_UNUSED2 to allow for
future uses of the PTE flag.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
-rw-r--r-- | arch/x86/include/asm/pgtable_types.h | 11 | ||||
-rw-r--r-- | arch/x86/mm/init_32.c | 2 | ||||
-rw-r--r-- | arch/x86/mm/init_64.c | 2 | ||||
-rw-r--r-- | arch/x86/pci/i386.c | 2 | ||||
-rw-r--r-- | arch/x86/xen/enlighten.c | 2 |
5 files changed, 7 insertions, 12 deletions
diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index f216963..cee83b2 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -23,7 +23,6 @@ #define _PAGE_BIT_SPECIAL _PAGE_BIT_SOFTW1 #define _PAGE_BIT_CPA_TEST _PAGE_BIT_SOFTW1 #define _PAGE_BIT_SPLITTING _PAGE_BIT_SOFTW2 /* only valid on a PSE pmd */ -#define _PAGE_BIT_IOMAP _PAGE_BIT_SOFTW2 /* flag used to indicate IO mapping */ #define _PAGE_BIT_HIDDEN _PAGE_BIT_SOFTW3 /* hidden by kmemcheck */ #define _PAGE_BIT_SOFT_DIRTY _PAGE_BIT_SOFTW3 /* software dirty tracking */ #define _PAGE_BIT_NX 63 /* No execute: only valid after cpuid check */ @@ -52,7 +51,7 @@ #define _PAGE_PSE (_AT(pteval_t, 1) << _PAGE_BIT_PSE) #define _PAGE_GLOBAL (_AT(pteval_t, 1) << _PAGE_BIT_GLOBAL) #define _PAGE_SOFTW1 (_AT(pteval_t, 1) << _PAGE_BIT_SOFTW1) -#define _PAGE_IOMAP (_AT(pteval_t, 1) << _PAGE_BIT_IOMAP) +#define _PAGE_SOFTW2 (_AT(pteval_t, 1) << _PAGE_BIT_SOFTW2) #define _PAGE_PAT (_AT(pteval_t, 1) << _PAGE_BIT_PAT) #define _PAGE_PAT_LARGE (_AT(pteval_t, 1) << _PAGE_BIT_PAT_LARGE) #define _PAGE_SPECIAL (_AT(pteval_t, 1) << _PAGE_BIT_SPECIAL) @@ -168,10 +167,10 @@ #define __PAGE_KERNEL_LARGE_NOCACHE (__PAGE_KERNEL | _PAGE_CACHE_UC | _PAGE_PSE) #define __PAGE_KERNEL_LARGE_EXEC (__PAGE_KERNEL_EXEC | _PAGE_PSE) -#define __PAGE_KERNEL_IO (__PAGE_KERNEL | _PAGE_IOMAP) -#define __PAGE_KERNEL_IO_NOCACHE (__PAGE_KERNEL_NOCACHE | _PAGE_IOMAP) -#define __PAGE_KERNEL_IO_UC_MINUS (__PAGE_KERNEL_UC_MINUS | _PAGE_IOMAP) -#define __PAGE_KERNEL_IO_WC (__PAGE_KERNEL_WC | _PAGE_IOMAP) +#define __PAGE_KERNEL_IO (__PAGE_KERNEL) +#define __PAGE_KERNEL_IO_NOCACHE (__PAGE_KERNEL_NOCACHE) +#define __PAGE_KERNEL_IO_UC_MINUS (__PAGE_KERNEL_UC_MINUS) +#define __PAGE_KERNEL_IO_WC (__PAGE_KERNEL_WC) #define PAGE_KERNEL __pgprot(__PAGE_KERNEL) #define PAGE_KERNEL_RO __pgprot(__PAGE_KERNEL_RO) diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index 7d05565..c8140e1 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -537,7 +537,7 @@ static void __init pagetable_init(void) permanent_kmaps_init(pgd_base); } -pteval_t __supported_pte_mask __read_mostly = ~(_PAGE_NX | _PAGE_GLOBAL | _PAGE_IOMAP); +pteval_t __supported_pte_mask __read_mostly = ~(_PAGE_NX | _PAGE_GLOBAL); EXPORT_SYMBOL_GPL(__supported_pte_mask); /* user-defined highmem size */ diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 5621c47..5d98476 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -151,7 +151,7 @@ early_param("gbpages", parse_direct_gbpages_on); * around without checking the pgd every time. */ -pteval_t __supported_pte_mask __read_mostly = ~_PAGE_IOMAP; +pteval_t __supported_pte_mask __read_mostly = ~0; EXPORT_SYMBOL_GPL(__supported_pte_mask); int force_personality32; diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c index 2ae525e..37c1435 100644 --- a/arch/x86/pci/i386.c +++ b/arch/x86/pci/i386.c @@ -442,8 +442,6 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma, */ prot |= _PAGE_CACHE_UC_MINUS; - prot |= _PAGE_IOMAP; /* creating a mapping for IO */ - vma->vm_page_prot = __pgprot(prot); if (io_remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff, diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index c0cb11f..be1cff5 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -1559,8 +1559,6 @@ asmlinkage __visible void __init xen_start_kernel(void) #endif __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD); - __supported_pte_mask |= _PAGE_IOMAP; - /* * Prevent page tables from being allocated in highmem, even * if CONFIG_HIGHPTE is enabled. |