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[209.132.180.67]) by mx.google.com with ESMTP id d1-v6si673244pld.515.2018.07.17.05.02.02; Tue, 17 Jul 2018 05:02:17 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731469AbeGQMdm (ORCPT + 99 others); Tue, 17 Jul 2018 08:33:42 -0400 Received: from mx2.suse.de ([195.135.220.15]:45740 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1731296AbeGQMdl (ORCPT ); Tue, 17 Jul 2018 08:33:41 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 287EBAF62; Tue, 17 Jul 2018 12:01:20 +0000 (UTC) From: Juergen Gross To: linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org, x86@kernel.org Cc: boris.ostrovsky@oracle.com, hpa@zytor.com, tglx@linutronix.de, mingo@redhat.com, Juergen Gross Subject: [PATCH 2/4] xen: move pv specific parts of arch/x86/xen/mmu.c to mmu_pv.c Date: Tue, 17 Jul 2018 14:01:11 +0200 Message-Id: <20180717120113.12756-3-jgross@suse.com> X-Mailer: git-send-email 2.13.7 In-Reply-To: <20180717120113.12756-1-jgross@suse.com> References: <20180717120113.12756-1-jgross@suse.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There are some PV specific functions in arch/x86/xen/mmu.c which can be moved to mmu_pv.c. This in turn enables us to make multicalls.c dependent on CONFIG_XEN_PV. Signed-off-by: Juergen Gross --- arch/x86/xen/Makefile | 2 +- arch/x86/xen/mmu.c | 186 ----------------------------------------- arch/x86/xen/mmu_pv.c | 138 ++++++++++++++++++++++++++++++ include/xen/interface/memory.h | 6 -- include/xen/xen-ops.h | 133 +++++++++++++++++++---------- 5 files changed, 227 insertions(+), 238 deletions(-) diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile index f723b5aa8f74..a964f307a266 100644 --- a/arch/x86/xen/Makefile +++ b/arch/x86/xen/Makefile @@ -15,7 +15,6 @@ CFLAGS_enlighten_pv.o := $(nostackp) CFLAGS_mmu_pv.o := $(nostackp) obj-y += enlighten.o -obj-y += multicalls.o obj-y += mmu.o obj-y += time.o obj-y += grant-table.o @@ -34,6 +33,7 @@ obj-$(CONFIG_XEN_PV) += p2m.o obj-$(CONFIG_XEN_PV) += enlighten_pv.o obj-$(CONFIG_XEN_PV) += mmu_pv.o obj-$(CONFIG_XEN_PV) += irq.o +obj-$(CONFIG_XEN_PV) += multicalls.o obj-$(CONFIG_XEN_PV) += xen-asm.o obj-$(CONFIG_XEN_PV) += xen-asm_$(BITS).o diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 96fc2f0fdbfe..e0e13fe16d37 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -6,12 +6,6 @@ #include "multicalls.h" #include "mmu.h" -/* - * Protects atomic reservation decrease/increase against concurrent increases. - * Also protects non-atomic updates of current_pages and balloon lists. - */ -DEFINE_SPINLOCK(xen_reservation_lock); - unsigned long arbitrary_virt_to_mfn(void *vaddr) { xmaddr_t maddr = arbitrary_virt_to_machine(vaddr); @@ -42,186 +36,6 @@ xmaddr_t arbitrary_virt_to_machine(void *vaddr) } EXPORT_SYMBOL_GPL(arbitrary_virt_to_machine); -static noinline void xen_flush_tlb_all(void) -{ - struct mmuext_op *op; - struct multicall_space mcs; - - preempt_disable(); - - mcs = xen_mc_entry(sizeof(*op)); - - op = mcs.args; - op->cmd = MMUEXT_TLB_FLUSH_ALL; - MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF); - - xen_mc_issue(PARAVIRT_LAZY_MMU); - - preempt_enable(); -} - -#define REMAP_BATCH_SIZE 16 - -struct remap_data { - xen_pfn_t *pfn; - bool contiguous; - bool no_translate; - pgprot_t prot; - struct mmu_update *mmu_update; -}; - -static int remap_area_pfn_pte_fn(pte_t *ptep, pgtable_t token, - unsigned long addr, void *data) -{ - struct remap_data *rmd = data; - pte_t pte = pte_mkspecial(mfn_pte(*rmd->pfn, rmd->prot)); - - /* - * If we have a contiguous range, just update the pfn itself, - * else update pointer to be "next pfn". - */ - if (rmd->contiguous) - (*rmd->pfn)++; - else - rmd->pfn++; - - rmd->mmu_update->ptr = virt_to_machine(ptep).maddr; - rmd->mmu_update->ptr |= rmd->no_translate ? - MMU_PT_UPDATE_NO_TRANSLATE : - MMU_NORMAL_PT_UPDATE; - rmd->mmu_update->val = pte_val_ma(pte); - rmd->mmu_update++; - - return 0; -} - -static int do_remap_pfn(struct vm_area_struct *vma, - unsigned long addr, - xen_pfn_t *pfn, int nr, - int *err_ptr, pgprot_t prot, - unsigned int domid, - bool no_translate, - struct page **pages) -{ - int err = 0; - struct remap_data rmd; - struct mmu_update mmu_update[REMAP_BATCH_SIZE]; - unsigned long range; - int mapped = 0; - - BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_IO)) == (VM_PFNMAP | VM_IO))); - - rmd.pfn = pfn; - rmd.prot = prot; - /* - * We use the err_ptr to indicate if there we are doing a contiguous - * mapping or a discontigious mapping. - */ - rmd.contiguous = !err_ptr; - rmd.no_translate = no_translate; - - while (nr) { - int index = 0; - int done = 0; - int batch = min(REMAP_BATCH_SIZE, nr); - int batch_left = batch; - range = (unsigned long)batch << PAGE_SHIFT; - - rmd.mmu_update = mmu_update; - err = apply_to_page_range(vma->vm_mm, addr, range, - remap_area_pfn_pte_fn, &rmd); - if (err) - goto out; - - /* We record the error for each page that gives an error, but - * continue mapping until the whole set is done */ - do { - int i; - - err = HYPERVISOR_mmu_update(&mmu_update[index], - batch_left, &done, domid); - - /* - * @err_ptr may be the same buffer as @gfn, so - * only clear it after each chunk of @gfn is - * used. - */ - if (err_ptr) { - for (i = index; i < index + done; i++) - err_ptr[i] = 0; - } - if (err < 0) { - if (!err_ptr) - goto out; - err_ptr[i] = err; - done++; /* Skip failed frame. */ - } else - mapped += done; - batch_left -= done; - index += done; - } while (batch_left); - - nr -= batch; - addr += range; - if (err_ptr) - err_ptr += batch; - cond_resched(); - } -out: - - xen_flush_tlb_all(); - - return err < 0 ? err : mapped; -} - -int xen_remap_domain_gfn_range(struct vm_area_struct *vma, - unsigned long addr, - xen_pfn_t gfn, int nr, - pgprot_t prot, unsigned domid, - struct page **pages) -{ - if (xen_feature(XENFEAT_auto_translated_physmap)) - return -EOPNOTSUPP; - - return do_remap_pfn(vma, addr, &gfn, nr, NULL, prot, domid, false, - pages); -} -EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_range); - -int xen_remap_domain_gfn_array(struct vm_area_struct *vma, - unsigned long addr, - xen_pfn_t *gfn, int nr, - int *err_ptr, pgprot_t prot, - unsigned domid, struct page **pages) -{ - if (xen_feature(XENFEAT_auto_translated_physmap)) - return xen_xlate_remap_gfn_array(vma, addr, gfn, nr, err_ptr, - prot, domid, pages); - - /* We BUG_ON because it's a programmer error to pass a NULL err_ptr, - * and the consequences later is quite hard to detect what the actual - * cause of "wrong memory was mapped in". - */ - BUG_ON(err_ptr == NULL); - return do_remap_pfn(vma, addr, gfn, nr, err_ptr, prot, domid, - false, pages); -} -EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_array); - -int xen_remap_domain_mfn_array(struct vm_area_struct *vma, - unsigned long addr, - xen_pfn_t *mfn, int nr, - int *err_ptr, pgprot_t prot, - unsigned int domid, struct page **pages) -{ - if (xen_feature(XENFEAT_auto_translated_physmap)) - return -EOPNOTSUPP; - - return do_remap_pfn(vma, addr, mfn, nr, err_ptr, prot, domid, - true, pages); -} -EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_array); - /* Returns: 0 success */ int xen_unmap_domain_gfn_range(struct vm_area_struct *vma, int nr, struct page **pages) diff --git a/arch/x86/xen/mmu_pv.c b/arch/x86/xen/mmu_pv.c index 2c30cabfda90..ea4b2f69dfce 100644 --- a/arch/x86/xen/mmu_pv.c +++ b/arch/x86/xen/mmu_pv.c @@ -98,6 +98,12 @@ static pud_t level3_user_vsyscall[PTRS_PER_PUD] __page_aligned_bss; #endif /* CONFIG_X86_64 */ /* + * Protects atomic reservation decrease/increase against concurrent increases. + * Also protects non-atomic updates of current_pages and balloon lists. + */ +DEFINE_SPINLOCK(xen_reservation_lock); + +/* * Note about cr3 (pagetable base) values: * * xen_cr3 contains the current logical cr3 value; it contains the @@ -2663,6 +2669,138 @@ void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order) } EXPORT_SYMBOL_GPL(xen_destroy_contiguous_region); +static noinline void xen_flush_tlb_all(void) +{ + struct mmuext_op *op; + struct multicall_space mcs; + + preempt_disable(); + + mcs = xen_mc_entry(sizeof(*op)); + + op = mcs.args; + op->cmd = MMUEXT_TLB_FLUSH_ALL; + MULTI_mmuext_op(mcs.mc, op, 1, NULL, DOMID_SELF); + + xen_mc_issue(PARAVIRT_LAZY_MMU); + + preempt_enable(); +} + +#define REMAP_BATCH_SIZE 16 + +struct remap_data { + xen_pfn_t *pfn; + bool contiguous; + bool no_translate; + pgprot_t prot; + struct mmu_update *mmu_update; +}; + +static int remap_area_pfn_pte_fn(pte_t *ptep, pgtable_t token, + unsigned long addr, void *data) +{ + struct remap_data *rmd = data; + pte_t pte = pte_mkspecial(mfn_pte(*rmd->pfn, rmd->prot)); + + /* + * If we have a contiguous range, just update the pfn itself, + * else update pointer to be "next pfn". + */ + if (rmd->contiguous) + (*rmd->pfn)++; + else + rmd->pfn++; + + rmd->mmu_update->ptr = virt_to_machine(ptep).maddr; + rmd->mmu_update->ptr |= rmd->no_translate ? + MMU_PT_UPDATE_NO_TRANSLATE : + MMU_NORMAL_PT_UPDATE; + rmd->mmu_update->val = pte_val_ma(pte); + rmd->mmu_update++; + + return 0; +} + +int xen_remap_pfn(struct vm_area_struct *vma, unsigned long addr, + xen_pfn_t *pfn, int nr, int *err_ptr, pgprot_t prot, + unsigned int domid, bool no_translate, struct page **pages) +{ + int err = 0; + struct remap_data rmd; + struct mmu_update mmu_update[REMAP_BATCH_SIZE]; + unsigned long range; + int mapped = 0; + + BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_IO)) == (VM_PFNMAP | VM_IO))); + + rmd.pfn = pfn; + rmd.prot = prot; + /* + * We use the err_ptr to indicate if there we are doing a contiguous + * mapping or a discontigious mapping. + */ + rmd.contiguous = !err_ptr; + rmd.no_translate = no_translate; + + while (nr) { + int index = 0; + int done = 0; + int batch = min(REMAP_BATCH_SIZE, nr); + int batch_left = batch; + + range = (unsigned long)batch << PAGE_SHIFT; + + rmd.mmu_update = mmu_update; + err = apply_to_page_range(vma->vm_mm, addr, range, + remap_area_pfn_pte_fn, &rmd); + if (err) + goto out; + + /* + * We record the error for each page that gives an error, but + * continue mapping until the whole set is done + */ + do { + int i; + + err = HYPERVISOR_mmu_update(&mmu_update[index], + batch_left, &done, domid); + + /* + * @err_ptr may be the same buffer as @gfn, so + * only clear it after each chunk of @gfn is + * used. + */ + if (err_ptr) { + for (i = index; i < index + done; i++) + err_ptr[i] = 0; + } + if (err < 0) { + if (!err_ptr) + goto out; + err_ptr[i] = err; + done++; /* Skip failed frame. */ + } else + mapped += done; + batch_left -= done; + index += done; + } while (batch_left); + + nr -= batch; + addr += range; + if (err_ptr) + err_ptr += batch; + cond_resched(); + } +out: + + xen_flush_tlb_all(); + + return err < 0 ? err : mapped; +} +EXPORT_SYMBOL_GPL(xen_remap_pfn); + #ifdef CONFIG_KEXEC_CORE phys_addr_t paddr_vmcoreinfo_note(void) { diff --git a/include/xen/interface/memory.h b/include/xen/interface/memory.h index 4c5751c26f87..447004861f00 100644 --- a/include/xen/interface/memory.h +++ b/include/xen/interface/memory.h @@ -245,12 +245,6 @@ DEFINE_GUEST_HANDLE_STRUCT(xen_memory_map); /* - * Prevent the balloon driver from changing the memory reservation - * during a driver critical region. - */ -extern spinlock_t xen_reservation_lock; - -/* * Unmaps the page appearing at a particular GPFN from the specified guest's * pseudophysical address space. * arg == addr of xen_remove_from_physmap_t. diff --git a/include/xen/xen-ops.h b/include/xen/xen-ops.h index fd18c974a619..18803ff76e27 100644 --- a/include/xen/xen-ops.h +++ b/include/xen/xen-ops.h @@ -5,6 +5,7 @@ #include #include #include +#include #include #include @@ -47,6 +48,10 @@ int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order, dma_addr_t *dma_handle); void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order); + +int xen_remap_pfn(struct vm_area_struct *vma, unsigned long addr, + xen_pfn_t *pfn, int nr, int *err_ptr, pgprot_t prot, + unsigned int domid, bool no_translate, struct page **pages); #else static inline int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order, @@ -58,10 +63,50 @@ static inline int xen_create_contiguous_region(phys_addr_t pstart, static inline void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order) { } + +static inline int xen_remap_pfn(struct vm_area_struct *vma, unsigned long addr, + xen_pfn_t *pfn, int nr, int *err_ptr, + pgprot_t prot, unsigned int domid, + bool no_translate, struct page **pages) +{ + BUG(); + return 0; +} #endif struct vm_area_struct; +#ifdef CONFIG_XEN_AUTO_XLATE +int xen_xlate_remap_gfn_array(struct vm_area_struct *vma, + unsigned long addr, + xen_pfn_t *gfn, int nr, + int *err_ptr, pgprot_t prot, + unsigned int domid, + struct page **pages); +int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma, + int nr, struct page **pages); +#else +/* + * These two functions are called from arch/x86/xen/mmu.c and so stubs + * are needed for a configuration not specifying CONFIG_XEN_AUTO_XLATE. + */ +static inline int xen_xlate_remap_gfn_array(struct vm_area_struct *vma, + unsigned long addr, + xen_pfn_t *gfn, int nr, + int *err_ptr, pgprot_t prot, + unsigned int domid, + struct page **pages) +{ + return -EOPNOTSUPP; +} + +static inline int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma, + int nr, struct page **pages) +{ + return -EOPNOTSUPP; +} +#endif + /* * xen_remap_domain_gfn_array() - map an array of foreign frames by gfn * @vma: VMA to map the pages into @@ -79,12 +124,25 @@ struct vm_area_struct; * Returns the number of successfully mapped frames, or a -ve error * code. */ -int xen_remap_domain_gfn_array(struct vm_area_struct *vma, - unsigned long addr, - xen_pfn_t *gfn, int nr, - int *err_ptr, pgprot_t prot, - unsigned domid, - struct page **pages); +static inline int xen_remap_domain_gfn_array(struct vm_area_struct *vma, + unsigned long addr, + xen_pfn_t *gfn, int nr, + int *err_ptr, pgprot_t prot, + unsigned int domid, + struct page **pages) +{ + if (xen_feature(XENFEAT_auto_translated_physmap)) + return xen_xlate_remap_gfn_array(vma, addr, gfn, nr, err_ptr, + prot, domid, pages); + + /* We BUG_ON because it's a programmer error to pass a NULL err_ptr, + * and the consequences later is quite hard to detect what the actual + * cause of "wrong memory was mapped in". + */ + BUG_ON(err_ptr == NULL); + return xen_remap_pfn(vma, addr, gfn, nr, err_ptr, prot, domid, + false, pages); +} /* * xen_remap_domain_mfn_array() - map an array of foreign frames by mfn @@ -103,10 +161,18 @@ int xen_remap_domain_gfn_array(struct vm_area_struct *vma, * Returns the number of successfully mapped frames, or a -ve error * code. */ -int xen_remap_domain_mfn_array(struct vm_area_struct *vma, - unsigned long addr, xen_pfn_t *mfn, int nr, - int *err_ptr, pgprot_t prot, - unsigned int domid, struct page **pages); +static inline int xen_remap_domain_mfn_array(struct vm_area_struct *vma, + unsigned long addr, xen_pfn_t *mfn, + int nr, int *err_ptr, + pgprot_t prot, unsigned int domid, + struct page **pages) +{ + if (xen_feature(XENFEAT_auto_translated_physmap)) + return -EOPNOTSUPP; + + return xen_remap_pfn(vma, addr, mfn, nr, err_ptr, prot, domid, + true, pages); +} /* xen_remap_domain_gfn_range() - map a range of foreign frames * @vma: VMA to map the pages into @@ -120,44 +186,21 @@ int xen_remap_domain_mfn_array(struct vm_area_struct *vma, * Returns the number of successfully mapped frames, or a -ve error * code. */ -int xen_remap_domain_gfn_range(struct vm_area_struct *vma, - unsigned long addr, - xen_pfn_t gfn, int nr, - pgprot_t prot, unsigned domid, - struct page **pages); -int xen_unmap_domain_gfn_range(struct vm_area_struct *vma, - int numpgs, struct page **pages); - -#ifdef CONFIG_XEN_AUTO_XLATE -int xen_xlate_remap_gfn_array(struct vm_area_struct *vma, - unsigned long addr, - xen_pfn_t *gfn, int nr, - int *err_ptr, pgprot_t prot, - unsigned domid, - struct page **pages); -int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma, - int nr, struct page **pages); -#else -/* - * These two functions are called from arch/x86/xen/mmu.c and so stubs - * are needed for a configuration not specifying CONFIG_XEN_AUTO_XLATE. - */ -static inline int xen_xlate_remap_gfn_array(struct vm_area_struct *vma, - unsigned long addr, - xen_pfn_t *gfn, int nr, - int *err_ptr, pgprot_t prot, - unsigned int domid, - struct page **pages) +static inline int xen_remap_domain_gfn_range(struct vm_area_struct *vma, + unsigned long addr, + xen_pfn_t gfn, int nr, + pgprot_t prot, unsigned int domid, + struct page **pages) { - return -EOPNOTSUPP; -} + if (xen_feature(XENFEAT_auto_translated_physmap)) + return -EOPNOTSUPP; -static inline int xen_xlate_unmap_gfn_range(struct vm_area_struct *vma, - int nr, struct page **pages) -{ - return -EOPNOTSUPP; + return xen_remap_pfn(vma, addr, &gfn, nr, NULL, prot, domid, false, + pages); } -#endif + +int xen_unmap_domain_gfn_range(struct vm_area_struct *vma, + int numpgs, struct page **pages); int xen_xlate_map_ballooned_pages(xen_pfn_t **pfns, void **vaddr, unsigned long nr_grant_frames); -- 2.13.7