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Xen's memory management APIs map_pages_to_xen, modify_xen_mappings, set_fixmap, ioremap_attr, and __vmap all use an unsigned int to represent architecture-dependent page table entry flags. This assumption is not well-suited for PPC/radix where some flags go past 32-bits, so introduce the pte_attr_t type to allow architectures to opt in to larger types to store PTE flags. Suggested-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx> Signed-off-by: Shawn Anastasio <sanastasio@xxxxxxxxxxxxxxxxxxxxx> --- Changes in v4: - Change definitions of map_pages_to_xen, modify_xen_mappings in all arches to match new prototype. - Use new flag types in modify_xen_mappings_lite as well (previously missed) Changes in v3: - Use new asm/mm-types.h to pull in pte_attr_t definition when necessary. - Drop define+ifdef since pte_attr_t is now always defined. Changes in v2: - Drop Kconfig option and use `#define pte_attr_t pte_attr_t` for arches to opt-in to defining the type. - Move default pte_attr_definition to xen/types.h - Update commit message to reflect that this change isn't strictly necessary for arches w/ >32bit pte flags xen/arch/arm/mmu/pt.c | 4 ++-- xen/arch/ppc/include/asm/Makefile | 1 - xen/arch/ppc/include/asm/mm-types.h | 7 +++++++ xen/arch/ppc/mm-radix.c | 2 +- xen/arch/riscv/pt.c | 2 +-

Also as the part of this patch the following changes should be considered (I can send that as a separate patch): $ git diff diff --git a/xen/arch/riscv/include/asm/fixmap.h b/xen/arch/riscv/include/asm/fixmap.h index e399a15f53..5990c964aa 100644 --- a/xen/arch/riscv/include/asm/fixmap.h +++ b/xen/arch/riscv/include/asm/fixmap.h @@ -33,7 +33,7 @@ extern pte_t xen_fixmap[]; /* Map a page in a fixmap entry */ -void set_fixmap(unsigned int map, mfn_t mfn, unsigned int flags); +void set_fixmap(unsigned int map, mfn_t mfn, pte_attr_t flags); /* Remove a mapping from a fixmap entry */ void clear_fixmap(unsigned int map); diff --git a/xen/arch/riscv/include/asm/page.h b/xen/arch/riscv/include/asm/page.h index 3904d42a71..e23d69214e 100644 --- a/xen/arch/riscv/include/asm/page.h +++ b/xen/arch/riscv/include/asm/page.h @@ -217,7 +217,7 @@ static inline pte_t read_pte(const pte_t *p) return read_atomic(p); } -static inline pte_t pte_from_mfn(mfn_t mfn, unsigned int flags) +static inline pte_t pte_from_mfn(mfn_t mfn, pte_attr_t flags) { unsigned long pte = (mfn_x(mfn) << PTE_PPN_SHIFT) | flags; return (pte_t){ .pte = pte }; diff --git a/xen/arch/riscv/pt.c b/xen/arch/riscv/pt.c index ef84b6b078..d6cc68b7db 100644 --- a/xen/arch/riscv/pt.c +++ b/xen/arch/riscv/pt.c @@ -25,7 +25,7 @@ static inline mfn_t get_root_page(void) * See the comment about the possible combination of (mfn, flags) in * the comment above pt_update(). */ -static bool pt_check_entry(pte_t entry, mfn_t mfn, unsigned int flags) +static bool pt_check_entry(pte_t entry, mfn_t mfn, pte_attr_t flags) { /* Sanity check when modifying an entry. */ if ( (flags & PTE_VALID) && mfn_eq(mfn, INVALID_MFN) ) @@ -260,7 +260,7 @@ pte_t pt_walk(vaddr_t va, unsigned int *pte_level) */ static int pt_update_entry(mfn_t root, vaddr_t virt, mfn_t mfn, unsigned int *target, - unsigned int flags) + pte_attr_t flags) { int rc; /* @@ -355,7 +355,7 @@ static int pt_update_entry(mfn_t root, vaddr_t virt, /* Return the level where mapping should be done */ static int pt_mapping_level(unsigned long vfn, mfn_t mfn, unsigned long nr, - unsigned int flags) + pte_attr_t flags) { unsigned int level = 0; unsigned long mask; @@ -409,7 +409,7 @@ static DEFINE_SPINLOCK(pt_lock); * inserting will be done. */ static int pt_update(vaddr_t virt, mfn_t mfn, - unsigned long nr_mfns, unsigned int flags) + unsigned long nr_mfns, pte_attr_t flags) { int rc = 0; unsigned long vfn = PFN_DOWN(virt); @@ -537,7 +537,7 @@ int __init populate_pt_range(unsigned long virt, unsigned long nr_mfns) } /* Map a 4k page in a fixmap entry */ -void set_fixmap(unsigned int map, mfn_t mfn, unsigned int flags) +void set_fixmap(unsigned int map, mfn_t mfn, pte_attr_t flags) { if ( map_pages_to_xen(FIXMAP_ADDR(map), mfn, 1, flags | PTE_SMALL) != 0 ) BUG(); ~ Oleksii

xen/arch/x86/mm.c | 6 +++--- xen/common/efi/boot.c | 5 +++-- xen/common/vmap.c | 2 +- xen/include/asm-generic/mm-types.h | 2 ++ xen/include/xen/mm.h | 7 ++++--- xen/include/xen/vmap.h | 4 +++- 11 files changed, 27 insertions(+), 15 deletions(-) create mode 100644 xen/arch/ppc/include/asm/mm-types.h diff --git a/xen/arch/arm/mmu/pt.c b/xen/arch/arm/mmu/pt.c index da28d669e7..9dc99db352 100644 --- a/xen/arch/arm/mmu/pt.c +++ b/xen/arch/arm/mmu/pt.c @@ -701,7 +701,7 @@ static int xen_pt_update(unsigned long virt, int map_pages_to_xen(unsigned long virt, mfn_t mfn, unsigned long nr_mfns, - unsigned int flags) + pte_attr_t flags) { return xen_pt_update(virt, mfn, nr_mfns, flags); } @@ -719,7 +719,7 @@ int destroy_xen_mappings(unsigned long s, unsigned long e) return xen_pt_update(s, INVALID_MFN, (e - s) >> PAGE_SHIFT, 0); } -int modify_xen_mappings(unsigned long s, unsigned long e, unsigned int nf) +int modify_xen_mappings(unsigned long s, unsigned long e, pte_attr_t nf) { ASSERT(IS_ALIGNED(s, PAGE_SIZE)); ASSERT(IS_ALIGNED(e, PAGE_SIZE)); diff --git a/xen/arch/ppc/include/asm/Makefile b/xen/arch/ppc/include/asm/Makefile index c0dbc68ac6..c989a7f89b 100644 --- a/xen/arch/ppc/include/asm/Makefile +++ b/xen/arch/ppc/include/asm/Makefile @@ -5,7 +5,6 @@ generic-y += div64.h generic-y += hardirq.h generic-y += hypercall.h generic-y += iocap.h -generic-y += mm-types.h generic-y += paging.h generic-y += percpu.h generic-y += perfc_defn.h diff --git a/xen/arch/ppc/include/asm/mm-types.h b/xen/arch/ppc/include/asm/mm-types.h new file mode 100644 index 0000000000..0cb850f4f6 --- /dev/null +++ b/xen/arch/ppc/include/asm/mm-types.h @@ -0,0 +1,7 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +#ifndef __ASM_PPC_MM_TYPES_H__ +#define __ASM_PPC_MM_TYPES_H__ + +typedef unsigned long pte_attr_t; + +#endif /* __ASM_PPC_MM_TYPES_H__ */ diff --git a/xen/arch/ppc/mm-radix.c b/xen/arch/ppc/mm-radix.c index 24232f3907..e02dffa7c5 100644 --- a/xen/arch/ppc/mm-radix.c +++ b/xen/arch/ppc/mm-radix.c @@ -265,7 +265,7 @@ int destroy_xen_mappings(unsigned long s, unsigned long e) int map_pages_to_xen(unsigned long virt, mfn_t mfn, unsigned long nr_mfns, - unsigned int flags) + pte_attr_t flags) { BUG_ON("unimplemented"); } diff --git a/xen/arch/riscv/pt.c b/xen/arch/riscv/pt.c index 857619d48d..918b1b91ab 100644 --- a/xen/arch/riscv/pt.c +++ b/xen/arch/riscv/pt.c @@ -504,7 +504,7 @@ static int pt_update(vaddr_t virt, mfn_t mfn, int map_pages_to_xen(unsigned long virt, mfn_t mfn, unsigned long nr_mfns, - unsigned int flags) + pte_attr_t flags) { /* * Ensure that flags has PTE_VALID bit as map_pages_to_xen() is supposed diff --git a/xen/arch/x86/mm.c b/xen/arch/x86/mm.c index bfdc8fb019..53c17c6f88 100644 --- a/xen/arch/x86/mm.c +++ b/xen/arch/x86/mm.c @@ -5472,7 +5472,7 @@ int map_pages_to_xen( unsigned long virt, mfn_t mfn, unsigned long nr_mfns, - unsigned int flags) + pte_attr_t flags) { bool locking = system_state > SYS_STATE_boot; l3_pgentry_t *pl3e = NULL, ol3e; @@ -5890,7 +5890,7 @@ int __init populate_pt_range(unsigned long virt, unsigned long nr_mfns) * * It is an error to call with present flags over an unpopulated range. */ -int modify_xen_mappings(unsigned long s, unsigned long e, unsigned int nf) +int modify_xen_mappings(unsigned long s, unsigned long e, pte_attr_t nf) { bool locking = system_state > SYS_STATE_boot; l3_pgentry_t *pl3e = NULL; @@ -6186,7 +6186,7 @@ int destroy_xen_mappings(unsigned long s, unsigned long e) * the non-inclusive boundary will be updated. */ void init_or_livepatch modify_xen_mappings_lite( - unsigned long s, unsigned long e, unsigned int nf) + unsigned long s, unsigned long e, pte_attr_t nf) { unsigned long v = s, fm, flags; diff --git a/xen/common/efi/boot.c b/xen/common/efi/boot.c index efbec00af9..999dbce4dc 100644 --- a/xen/common/efi/boot.c +++ b/xen/common/efi/boot.c @@ -1,4 +1,5 @@ #include "efi.h" +#include <asm/mm-types.h> #include <efi/efiprot.h> #include <efi/efipciio.h> #include <public/xen.h> @@ -1656,7 +1657,7 @@ void __init efi_init_memory(void) struct rt_extra { struct rt_extra *next; unsigned long smfn, emfn; - unsigned int prot; + pte_attr_t prot; } *extra, *extra_head = NULL; free_ebmalloc_unused_mem(); @@ -1671,7 +1672,7 @@ void __init efi_init_memory(void) EFI_MEMORY_DESCRIPTOR *desc = efi_memmap + i; u64 len = desc->NumberOfPages << EFI_PAGE_SHIFT; unsigned long smfn, emfn; - unsigned int prot = PAGE_HYPERVISOR_RWX; + pte_attr_t prot = PAGE_HYPERVISOR_RWX; paddr_t mem_base; unsigned long mem_npages; diff --git a/xen/common/vmap.c b/xen/common/vmap.c index 47225fecc0..d6991421f3 100644 --- a/xen/common/vmap.c +++ b/xen/common/vmap.c @@ -222,7 +222,7 @@ static void vm_free(const void *va) } void *__vmap(const mfn_t *mfn, unsigned int granularity, - unsigned int nr, unsigned int align, unsigned int flags, + unsigned int nr, unsigned int align, pte_attr_t flags, enum vmap_region type) { void *va = vm_alloc(nr * granularity, align, type); diff --git a/xen/include/asm-generic/mm-types.h b/xen/include/asm-generic/mm-types.h index 26490e48db..9eb3cba698 100644 --- a/xen/include/asm-generic/mm-types.h +++ b/xen/include/asm-generic/mm-types.h @@ -2,4 +2,6 @@ #ifndef __ASM_GENERIC_MM_TYPES_H__ #define __ASM_GENERIC_MM_TYPES_H__ +typedef unsigned int pte_attr_t; + #endif /* __ASM_GENERIC_MM_TYPES_H__ */ diff --git a/xen/include/xen/mm.h b/xen/include/xen/mm.h index 16f733281a..e79f1728c3 100644 --- a/xen/include/xen/mm.h +++ b/xen/include/xen/mm.h @@ -69,6 +69,7 @@ #include <xen/spinlock.h> #include <xen/perfc.h> #include <public/memory.h> +#include <asm/mm-types.h> struct page_info; @@ -113,11 +114,11 @@ int map_pages_to_xen( unsigned long virt, mfn_t mfn, unsigned long nr_mfns, - unsigned int flags); + pte_attr_t flags); /* Alter the permissions of a range of Xen virtual address space. */ -int modify_xen_mappings(unsigned long s, unsigned long e, unsigned int nf); +int modify_xen_mappings(unsigned long s, unsigned long e, pte_attr_t nf); void modify_xen_mappings_lite(unsigned long s, unsigned long e, - unsigned int nf); + pte_attr_t nf); int destroy_xen_mappings(unsigned long s, unsigned long e); /* Retrieve the MFN mapped by VA in Xen virtual address space. */ mfn_t xen_map_to_mfn(unsigned long va); diff --git a/xen/include/xen/vmap.h b/xen/include/xen/vmap.h index 26c831757a..e1155ed14a 100644 --- a/xen/include/xen/vmap.h +++ b/xen/include/xen/vmap.h @@ -8,8 +8,10 @@ #ifndef __XEN_VMAP_H__ #define __XEN_VMAP_H__ +#include <xen/mm.h> #include <xen/mm-frame.h> #include <xen/page-size.h> +#include <asm/mm-types.h> /* Identifiers for the linear ranges tracked by vmap */ enum vmap_region { @@ -57,7 +59,7 @@ void vm_init_type(enum vmap_region type, void *start, void *end); * @return Pointer to the mapped area on success; NULL otherwise. */ void *__vmap(const mfn_t *mfn, unsigned int granularity, unsigned int nr, - unsigned int align, unsigned int flags, enum vmap_region type); + unsigned int align, pte_attr_t flags, enum vmap_region type); /* * Map an array of pages contiguously into the VMAP_DEFAULT vmap region -- 2.30.2

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Re: [PATCH v4 2/2] xen/mm: Introduce per-arch pte_attr_t type for PTE flags