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[Xen-devel] [PATCH v3 02/16] xen/arm: mm: Use typesafe mfn for xenheap_mfn_*

From: Julien Grall <julien.grall@xxxxxxx>

Date: Fri, 30 Jun 2017 16:54:17 +0100

Cc: Julien Grall <julien.grall@xxxxxxx>, sstabellini@xxxxxxxxxx

Delivery-date: Fri, 30 Jun 2017 15:54:42 +0000

List-id: Xen developer discussion <xen-devel.lists.xen.org>

Add more safety when using xenheap_mfn_*. Signed-off-by: Julien Grall <julien.grall@xxxxxxx> --- I haven't introduced mfn_less_than() and mfn_greather_than() as there would be only a couple of usage. We would be able to introduce them and replace the open-coding easily in the future grepping mfn_x(). Changes in v3: - Use INVALID_MFN_INITIALIZER rather than INVALID_MFN --- xen/arch/arm/mm.c | 16 ++++++++-------- xen/arch/arm/setup.c | 18 +++++++++--------- xen/include/asm-arm/mm.h | 11 ++++++----- 3 files changed, 23 insertions(+), 22 deletions(-) diff --git a/xen/arch/arm/mm.c b/xen/arch/arm/mm.c index 018f44a6d1..d3674e732e 100644 --- a/xen/arch/arm/mm.c +++ b/xen/arch/arm/mm.c @@ -138,8 +138,8 @@ uint64_t init_ttbr; static paddr_t phys_offset; /* Limits of the Xen heap */ -unsigned long xenheap_mfn_start __read_mostly = ~0UL; -unsigned long xenheap_mfn_end __read_mostly; +mfn_t xenheap_mfn_start __read_mostly = INVALID_MFN_INITIALIZER; +mfn_t xenheap_mfn_end __read_mostly; vaddr_t xenheap_virt_end __read_mostly; #ifdef CONFIG_ARM_64 vaddr_t xenheap_virt_start __read_mostly; @@ -801,8 +801,8 @@ void __init setup_xenheap_mappings(unsigned long base_mfn, /* Record where the xenheap is, for translation routines. */ xenheap_virt_end = XENHEAP_VIRT_START + nr_mfns * PAGE_SIZE; - xenheap_mfn_start = base_mfn; - xenheap_mfn_end = base_mfn + nr_mfns; + xenheap_mfn_start = _mfn(base_mfn); + xenheap_mfn_end = _mfn(base_mfn + nr_mfns); } #else /* CONFIG_ARM_64 */ void __init setup_xenheap_mappings(unsigned long base_mfn, @@ -816,16 +816,16 @@ void __init setup_xenheap_mappings(unsigned long base_mfn, mfn = base_mfn & ~((FIRST_SIZE>>PAGE_SHIFT)-1); /* First call sets the xenheap physical and virtual offset. */ - if ( xenheap_mfn_start == ~0UL ) + if ( mfn_eq(xenheap_mfn_start, INVALID_MFN) ) { - xenheap_mfn_start = base_mfn; + xenheap_mfn_start = _mfn(base_mfn); xenheap_virt_start = DIRECTMAP_VIRT_START + (base_mfn - mfn) * PAGE_SIZE; } - if ( base_mfn < xenheap_mfn_start ) + if ( base_mfn < mfn_x(xenheap_mfn_start) ) panic("cannot add xenheap mapping at %lx below heap start %lx", - base_mfn, xenheap_mfn_start); + base_mfn, mfn_x(xenheap_mfn_start)); end_mfn = base_mfn + nr_mfns; diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c index ab4d8e4218..3b34855668 100644 --- a/xen/arch/arm/setup.c +++ b/xen/arch/arm/setup.c @@ -555,8 +555,8 @@ static void __init setup_mm(unsigned long dtb_paddr, size_t dtb_size) * and enough mapped pages for copying the DTB. */ dtb_pages = (dtb_size + PAGE_SIZE-1) >> PAGE_SHIFT; - boot_mfn_start = xenheap_mfn_end - dtb_pages - 1; - boot_mfn_end = xenheap_mfn_end; + boot_mfn_start = mfn_x(xenheap_mfn_end) - dtb_pages - 1; + boot_mfn_end = mfn_x(xenheap_mfn_end); init_boot_pages(pfn_to_paddr(boot_mfn_start), pfn_to_paddr(boot_mfn_end)); @@ -591,11 +591,11 @@ static void __init setup_mm(unsigned long dtb_paddr, size_t dtb_size) e = bank_end; /* Avoid the xenheap */ - if ( s < pfn_to_paddr(xenheap_mfn_start+xenheap_pages) - && pfn_to_paddr(xenheap_mfn_start) < e ) + if ( s < mfn_to_maddr(mfn_add(xenheap_mfn_start, xenheap_pages)) + && mfn_to_maddr(xenheap_mfn_start) < e ) { - e = pfn_to_paddr(xenheap_mfn_start); - n = pfn_to_paddr(xenheap_mfn_start+xenheap_pages); + e = mfn_to_maddr(xenheap_mfn_start); + n = mfn_to_maddr(mfn_add(xenheap_mfn_start, xenheap_pages)); } dt_unreserved_regions(s, e, init_boot_pages, 0); @@ -610,7 +610,7 @@ static void __init setup_mm(unsigned long dtb_paddr, size_t dtb_size) /* Add xenheap memory that was not already added to the boot allocator. */ - init_xenheap_pages(pfn_to_paddr(xenheap_mfn_start), + init_xenheap_pages(mfn_to_maddr(xenheap_mfn_start), pfn_to_paddr(boot_mfn_start)); } #else /* CONFIG_ARM_64 */ @@ -662,8 +662,8 @@ static void __init setup_mm(unsigned long dtb_paddr, size_t dtb_size) total_pages += ram_size >> PAGE_SHIFT; xenheap_virt_end = XENHEAP_VIRT_START + ram_end - ram_start; - xenheap_mfn_start = ram_start >> PAGE_SHIFT; - xenheap_mfn_end = ram_end >> PAGE_SHIFT; + xenheap_mfn_start = maddr_to_mfn(ram_start); + xenheap_mfn_end = maddr_to_mfn(ram_end); /* * Need enough mapped pages for copying the DTB. diff --git a/xen/include/asm-arm/mm.h b/xen/include/asm-arm/mm.h index ddb3f35ed1..7a35063546 100644 --- a/xen/include/asm-arm/mm.h +++ b/xen/include/asm-arm/mm.h @@ -107,7 +107,7 @@ struct page_info #define PGC_count_width PG_shift(9) #define PGC_count_mask ((1UL<<PGC_count_width)-1) -extern unsigned long xenheap_mfn_start, xenheap_mfn_end; +extern mfn_t xenheap_mfn_start, xenheap_mfn_end; extern vaddr_t xenheap_virt_end; #ifdef CONFIG_ARM_64 extern vaddr_t xenheap_virt_start; @@ -117,7 +117,8 @@ extern vaddr_t xenheap_virt_start; #define is_xen_heap_page(page) is_xen_heap_mfn(page_to_mfn(page)) #define is_xen_heap_mfn(mfn) ({ \ unsigned long _mfn = (mfn); \ - (_mfn >= xenheap_mfn_start && _mfn < xenheap_mfn_end); \ + (_mfn >= mfn_x(xenheap_mfn_start) && \ + _mfn < mfn_x(xenheap_mfn_end)); \ }) #else #define is_xen_heap_page(page) ((page)->count_info & PGC_xen_heap) @@ -227,7 +228,7 @@ static inline paddr_t __virt_to_maddr(vaddr_t va) static inline void *maddr_to_virt(paddr_t ma) { ASSERT(is_xen_heap_mfn(ma >> PAGE_SHIFT)); - ma -= pfn_to_paddr(xenheap_mfn_start); + ma -= mfn_to_maddr(xenheap_mfn_start); return (void *)(unsigned long) ma + XENHEAP_VIRT_START; } #else @@ -235,7 +236,7 @@ static inline void *maddr_to_virt(paddr_t ma) { ASSERT(pfn_to_pdx(ma >> PAGE_SHIFT) < (DIRECTMAP_SIZE >> PAGE_SHIFT)); return (void *)(XENHEAP_VIRT_START - - pfn_to_paddr(xenheap_mfn_start) + + mfn_to_maddr(xenheap_mfn_start) + ((ma & ma_va_bottom_mask) | ((ma & ma_top_mask) >> pfn_pdx_hole_shift))); } @@ -276,7 +277,7 @@ static inline struct page_info *virt_to_page(const void *v) ASSERT(va < xenheap_virt_end); pdx = (va - XENHEAP_VIRT_START) >> PAGE_SHIFT; - pdx += pfn_to_pdx(xenheap_mfn_start); + pdx += pfn_to_pdx(mfn_x(xenheap_mfn_start)); return frame_table + pdx - frametable_base_pdx; } -- 2.11.0 _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxx https://lists.xen.org/xen-devel

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