The patch titled paravirt_ops: add kmap_atomic_pte for mapping highpte pages has been removed from the -mm tree. Its filename was paravirt_ops-add-kmap_atomic_pte-for-mapping-highpte-pages.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ Subject: paravirt_ops: add kmap_atomic_pte for mapping highpte pages From: Jeremy Fitzhardinge <jeremy@xxxxxxxx> Xen and VMI both have special requirements when mapping a highmem pte page into the kernel address space. These can be dealt with by adding a new kmap_atomic_pte() function for mapping highptes, and hooking it into the paravirt_ops infrastructure. Xen specifically wants to map the pte page RO, so this patch exposes a helper function, kmap_atomic_prot, which maps the page with the specified page protections. This also adds a kmap_flush_unused() function to clear out the cached kmap mappings. Xen needs this to clear out any potential stray RW mappings of pages which will become part of a pagetable. [ Zach - vmi.c will need some attention after this patch. It wasn't immediately obvious to me what needs to be done. ] Signed-off-by: Jeremy Fitzhardinge <jeremy@xxxxxxxxxxxxx> Cc: Zachary Amsden <zach@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/i386/kernel/paravirt.c | 7 +++++++ arch/i386/mm/highmem.c | 9 +++++++-- include/asm-i386/highmem.h | 11 +++++++++++ include/asm-i386/paravirt.h | 11 +++++++++++ include/asm-i386/pgtable.h | 4 ++-- include/linux/highmem.h | 6 ++++++ mm/highmem.c | 9 +++++++++ 7 files changed, 53 insertions(+), 4 deletions(-) diff -puN arch/i386/kernel/paravirt.c~paravirt_ops-add-kmap_atomic_pte-for-mapping-highpte-pages arch/i386/kernel/paravirt.c --- a/arch/i386/kernel/paravirt.c~paravirt_ops-add-kmap_atomic_pte-for-mapping-highpte-pages +++ a/arch/i386/kernel/paravirt.c @@ -20,6 +20,7 @@ #include <linux/efi.h> #include <linux/bcd.h> #include <linux/start_kernel.h> +#include <linux/highmem.h> #include <asm/bug.h> #include <asm/paravirt.h> @@ -316,6 +317,12 @@ struct paravirt_ops paravirt_ops = { .ptep_get_and_clear = native_ptep_get_and_clear, +#ifdef CONFIG_HIGHPTE + .kmap_atomic_pte = native_kmap_atomic_pte, +#else + .kmap_atomic_pte = paravirt_nop, +#endif + #ifdef CONFIG_X86_PAE .set_pte_atomic = native_set_pte_atomic, .set_pte_present = native_set_pte_present, diff -puN arch/i386/mm/highmem.c~paravirt_ops-add-kmap_atomic_pte-for-mapping-highpte-pages arch/i386/mm/highmem.c --- a/arch/i386/mm/highmem.c~paravirt_ops-add-kmap_atomic_pte-for-mapping-highpte-pages +++ a/arch/i386/mm/highmem.c @@ -26,7 +26,7 @@ void kunmap(struct page *page) * However when holding an atomic kmap is is not legal to sleep, so atomic * kmaps are appropriate for short, tight code paths only. */ -void *kmap_atomic(struct page *page, enum km_type type) +void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot) { enum fixed_addresses idx; unsigned long vaddr; @@ -41,11 +41,16 @@ void *kmap_atomic(struct page *page, enu return page_address(page); vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); - set_pte(kmap_pte-idx, mk_pte(page, kmap_prot)); + set_pte(kmap_pte-idx, mk_pte(page, prot)); return (void*) vaddr; } +void *kmap_atomic(struct page *page, enum km_type type) +{ + return kmap_atomic_prot(page, type, kmap_prot); +} + void kunmap_atomic(void *kvaddr, enum km_type type) { unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK; diff -puN include/asm-i386/highmem.h~paravirt_ops-add-kmap_atomic_pte-for-mapping-highpte-pages include/asm-i386/highmem.h --- a/include/asm-i386/highmem.h~paravirt_ops-add-kmap_atomic_pte-for-mapping-highpte-pages +++ a/include/asm-i386/highmem.h @@ -24,6 +24,7 @@ #include <linux/threads.h> #include <asm/kmap_types.h> #include <asm/tlbflush.h> +#include <asm/paravirt.h> /* declarations for highmem.c */ extern unsigned long highstart_pfn, highend_pfn; @@ -67,11 +68,21 @@ extern void FASTCALL(kunmap_high(struct void *kmap(struct page *page); void kunmap(struct page *page); +void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot); void *kmap_atomic(struct page *page, enum km_type type); void kunmap_atomic(void *kvaddr, enum km_type type); void *kmap_atomic_pfn(unsigned long pfn, enum km_type type); struct page *kmap_atomic_to_page(void *ptr); +static inline void *native_kmap_atomic_pte(struct page *page, enum km_type type) +{ + return kmap_atomic(page, type); +} + +#ifndef CONFIG_PARAVIRT +#define kmap_atomic_pte(page, type) kmap_atomic(page, type) +#endif + #define flush_cache_kmaps() do { } while (0) #endif /* __KERNEL__ */ diff -puN include/asm-i386/paravirt.h~paravirt_ops-add-kmap_atomic_pte-for-mapping-highpte-pages include/asm-i386/paravirt.h --- a/include/asm-i386/paravirt.h~paravirt_ops-add-kmap_atomic_pte-for-mapping-highpte-pages +++ a/include/asm-i386/paravirt.h @@ -16,7 +16,9 @@ #ifndef __ASSEMBLY__ #include <linux/types.h> #include <linux/cpumask.h> +#include <asm/kmap_types.h> +struct page; struct thread_struct; struct Xgt_desc_struct; struct tss_struct; @@ -187,6 +189,8 @@ struct paravirt_ops pte_t (*ptep_get_and_clear)(pte_t *ptep); + void *(*kmap_atomic_pte)(struct page *page, enum km_type type); + #ifdef CONFIG_X86_PAE void (*set_pte_atomic)(pte_t *ptep, pte_t pteval); void (*set_pte_present)(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pte); @@ -754,6 +758,13 @@ static inline void paravirt_release_pd(u PVOP_VCALL1(release_pd, pfn); } +static inline void *kmap_atomic_pte(struct page *page, enum km_type type) +{ + unsigned long ret; + ret = PVOP_CALL2(unsigned long, kmap_atomic_pte, page, type); + return (void *)ret; +} + static inline void pte_update(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { diff -puN include/asm-i386/pgtable.h~paravirt_ops-add-kmap_atomic_pte-for-mapping-highpte-pages include/asm-i386/pgtable.h --- a/include/asm-i386/pgtable.h~paravirt_ops-add-kmap_atomic_pte-for-mapping-highpte-pages +++ a/include/asm-i386/pgtable.h @@ -476,9 +476,9 @@ extern pte_t *lookup_address(unsigned lo #if defined(CONFIG_HIGHPTE) #define pte_offset_map(dir, address) \ - ((pte_t *)kmap_atomic(pmd_page(*(dir)),KM_PTE0) + pte_index(address)) + ((pte_t *)kmap_atomic_pte(pmd_page(*(dir)),KM_PTE0) + pte_index(address)) #define pte_offset_map_nested(dir, address) \ - ((pte_t *)kmap_atomic(pmd_page(*(dir)),KM_PTE1) + pte_index(address)) + ((pte_t *)kmap_atomic_pte(pmd_page(*(dir)),KM_PTE1) + pte_index(address)) #define pte_unmap(pte) kunmap_atomic(pte, KM_PTE0) #define pte_unmap_nested(pte) kunmap_atomic(pte, KM_PTE1) #else diff -puN include/linux/highmem.h~paravirt_ops-add-kmap_atomic_pte-for-mapping-highpte-pages include/linux/highmem.h --- a/include/linux/highmem.h~paravirt_ops-add-kmap_atomic_pte-for-mapping-highpte-pages +++ a/include/linux/highmem.h @@ -27,6 +27,8 @@ static inline void flush_kernel_dcache_p unsigned int nr_free_highpages(void); extern unsigned long totalhigh_pages; +void kmap_flush_unused(void); + #else /* CONFIG_HIGHMEM */ static inline unsigned int nr_free_highpages(void) { return 0; } @@ -44,9 +46,13 @@ static inline void *kmap(struct page *pa #define kmap_atomic(page, idx) \ ({ pagefault_disable(); page_address(page); }) +#define kmap_atomic_prot(page, idx, prot) kmap_atomic(page, idx) + #define kunmap_atomic(addr, idx) do { pagefault_enable(); } while (0) #define kmap_atomic_pfn(pfn, idx) kmap_atomic(pfn_to_page(pfn), (idx)) #define kmap_atomic_to_page(ptr) virt_to_page(ptr) + +#define kmap_flush_unused() do {} while(0) #endif #endif /* CONFIG_HIGHMEM */ diff -puN mm/highmem.c~paravirt_ops-add-kmap_atomic_pte-for-mapping-highpte-pages mm/highmem.c --- a/mm/highmem.c~paravirt_ops-add-kmap_atomic_pte-for-mapping-highpte-pages +++ a/mm/highmem.c @@ -99,6 +99,15 @@ static void flush_all_zero_pkmaps(void) flush_tlb_kernel_range(PKMAP_ADDR(0), PKMAP_ADDR(LAST_PKMAP)); } +/* Flush all unused kmap mappings in order to remove stray + mappings. */ +void kmap_flush_unused(void) +{ + spin_lock(&kmap_lock); + flush_all_zero_pkmaps(); + spin_unlock(&kmap_lock); +} + static inline unsigned long map_new_virtual(struct page *page) { unsigned long vaddr; _ Patches currently in -mm which might be from jeremy@xxxxxxxx are origin.patch revert-proper-fix-for-highmem-kmap_atomic-functions-for-vmi-for-2621.patch revert-x86_64-mm-account-for-module-percpu-space-separately-from-kernel-percpu.patch add-apply_to_page_range-which-applies-a-function-to-a-pte-range.patch rename-the-parainstructions-symbols-to-be-consistent-with-the-others.patch rename-the-parainstructions-symbols-to-be-consistent-with-the-others-fix.patch allow-boot-time-disable-of-paravirt_ops-patching.patch x86-clean-up-identify_cpu-update.patch i386-map-enough-initial-memory-to-create-lowmem-mappings.patch mm-only-i386-for-debugging-make-the-initial-page-table-setup-less-forgiving.patch maps2-uninline-some-functions-in-the-page-walker.patch maps2-eliminate-the-pmd_walker-struct-in-the-page-walker.patch maps2-remove-vma-from-args-in-the-page-walker.patch maps2-propagate-errors-from-callback-in-page-walker.patch maps2-add-callbacks-for-each-level-to-page-walker.patch maps2-move-the-page-walker-code-to-lib.patch maps2-move-the-page-walker-code-to-lib-fix.patch maps2-simplify-interdependence-of-proc-pid-maps-and-smaps.patch maps2-move-clear_refs-code-to-task_mmuc.patch maps2-regroup-task_mmu-by-interface.patch maps2-make-proc-pid-smaps-optional-under-config_embedded.patch maps2-make-proc-pid-clear_refs-option-under-config_embedded.patch maps2-add-proc-pid-pagemap-interface.patch maps2-add-proc-kpagemap-interface.patch fixes-and-cleanups-for-earlyprintk-aka-boot-console.patch ignore-stolen-time-in-the-softlockup-watchdog.patch add-touch_all_softlockup_watchdogs.patch clean-up-elf-note-generation.patch deflate-stack-usage-in-lib-inflatec.patch - To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html