From a8a93f3f03b7a8008d720e8d91798efe599d416c Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Thu, 12 Feb 2009 13:45:34 -0800 Subject: mm: disable preemption in apply_to_pte_range Impact: bugfix Lazy mmu mode needs preemption disabled, so if we're apply to init_mm (which doesn't require any pte locks), then explicitly disable preemption. (Do it unconditionally after checking we've successfully done the allocation to simplify the error handling.) Signed-off-by: Jeremy Fitzhardinge --- mm/memory.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/memory.c b/mm/memory.c index baa999e87cd2..b80cc31292b1 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1718,6 +1718,7 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, BUG_ON(pmd_huge(*pmd)); + preempt_disable(); arch_enter_lazy_mmu_mode(); token = pmd_pgtable(*pmd); @@ -1729,6 +1730,7 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, } while (pte++, addr += PAGE_SIZE, addr != end); arch_leave_lazy_mmu_mode(); + preempt_enable(); if (mm != &init_mm) pte_unmap_unlock(pte-1, ptl); -- cgit v1.2.3 From b8bcfe997e46150fedcc3f5b26b846400122fdd9 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Tue, 17 Feb 2009 23:05:19 -0800 Subject: x86/paravirt: remove lazy mode in interrupts Impact: simplification, robustness Make paravirt_lazy_mode() always return PARAVIRT_LAZY_NONE when in an interrupt. This prevents interrupt code from accidentally inheriting an outer lazy state, and instead does everything synchronously. Outer batched operations are left deferred. Signed-off-by: Jeremy Fitzhardinge Acked-by: Peter Zijlstra Cc: Thomas Gleixner --- arch/x86/kernel/paravirt.c | 3 +++ arch/x86/mm/fault.c | 6 ++---- arch/x86/mm/highmem_32.c | 2 -- arch/x86/mm/iomap_32.c | 1 - arch/x86/mm/pageattr.c | 14 -------------- 5 files changed, 5 insertions(+), 21 deletions(-) diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index 63dd358d8ee1..8ab250ac498b 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -282,6 +282,9 @@ void paravirt_leave_lazy_cpu(void) enum paravirt_lazy_mode paravirt_get_lazy_mode(void) { + if (in_interrupt()) + return PARAVIRT_LAZY_NONE; + return __get_cpu_var(paravirt_lazy_mode); } diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index a03b7279efa0..cfbb4a738011 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -225,12 +225,10 @@ static inline pmd_t *vmalloc_sync_one(pgd_t *pgd, unsigned long address) if (!pmd_present(*pmd_k)) return NULL; - if (!pmd_present(*pmd)) { + if (!pmd_present(*pmd)) set_pmd(pmd, *pmd_k); - arch_flush_lazy_mmu_mode(); - } else { + else BUG_ON(pmd_page(*pmd) != pmd_page(*pmd_k)); - } return pmd_k; } diff --git a/arch/x86/mm/highmem_32.c b/arch/x86/mm/highmem_32.c index 00f127c80b0e..e81dfa408157 100644 --- a/arch/x86/mm/highmem_32.c +++ b/arch/x86/mm/highmem_32.c @@ -87,7 +87,6 @@ void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot) vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); BUG_ON(!pte_none(*(kmap_pte-idx))); set_pte(kmap_pte-idx, mk_pte(page, prot)); - arch_flush_lazy_mmu_mode(); return (void *)vaddr; } @@ -117,7 +116,6 @@ void kunmap_atomic(void *kvaddr, enum km_type type) #endif } - arch_flush_lazy_mmu_mode(); pagefault_enable(); } diff --git a/arch/x86/mm/iomap_32.c b/arch/x86/mm/iomap_32.c index 04102d42ff42..b6a61f3d7ef8 100644 --- a/arch/x86/mm/iomap_32.c +++ b/arch/x86/mm/iomap_32.c @@ -74,7 +74,6 @@ iounmap_atomic(void *kvaddr, enum km_type type) if (vaddr == __fix_to_virt(FIX_KMAP_BEGIN+idx)) kpte_clear_flush(kmap_pte-idx, vaddr); - arch_flush_lazy_mmu_mode(); pagefault_enable(); } EXPORT_SYMBOL_GPL(iounmap_atomic); diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 9c4294986af7..9015e5e412b5 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -824,13 +824,6 @@ static int change_page_attr_set_clr(unsigned long *addr, int numpages, vm_unmap_aliases(); - /* - * If we're called with lazy mmu updates enabled, the - * in-memory pte state may be stale. Flush pending updates to - * bring them up to date. - */ - arch_flush_lazy_mmu_mode(); - cpa.vaddr = addr; cpa.numpages = numpages; cpa.mask_set = mask_set; @@ -873,13 +866,6 @@ static int change_page_attr_set_clr(unsigned long *addr, int numpages, } else cpa_flush_all(cache); - /* - * If we've been called with lazy mmu updates enabled, then - * make sure that everything gets flushed out before we - * return. - */ - arch_flush_lazy_mmu_mode(); - out: return ret; } -- cgit v1.2.3 From 7fd7d83d49914f03aefffba6aee09032fcd54cce Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Tue, 17 Feb 2009 23:24:03 -0800 Subject: x86/pvops: replace arch_enter_lazy_cpu_mode with arch_start_context_switch Impact: simplification, prepare for later changes Make lazy cpu mode more specific to context switching, so that it makes sense to do more context-switch specific things in the callbacks. Signed-off-by: Jeremy Fitzhardinge Acked-by: Peter Zijlstra --- arch/x86/include/asm/paravirt.h | 8 +++----- arch/x86/kernel/paravirt.c | 13 ------------- arch/x86/kernel/process_32.c | 2 +- arch/x86/kernel/process_64.c | 2 +- arch/x86/xen/mmu.c | 5 +---- include/asm-frv/pgtable.h | 4 ++-- include/asm-generic/pgtable.h | 21 +++++++++++---------- kernel/sched.c | 2 +- 8 files changed, 20 insertions(+), 37 deletions(-) diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index 0617d5cc9712..7b28abac323f 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -1420,19 +1420,17 @@ void paravirt_enter_lazy_mmu(void); void paravirt_leave_lazy_mmu(void); void paravirt_leave_lazy(enum paravirt_lazy_mode mode); -#define __HAVE_ARCH_ENTER_LAZY_CPU_MODE -static inline void arch_enter_lazy_cpu_mode(void) +#define __HAVE_ARCH_START_CONTEXT_SWITCH +static inline void arch_start_context_switch(void) { PVOP_VCALL0(pv_cpu_ops.lazy_mode.enter); } -static inline void arch_leave_lazy_cpu_mode(void) +static inline void arch_end_context_switch(void) { PVOP_VCALL0(pv_cpu_ops.lazy_mode.leave); } -void arch_flush_lazy_cpu_mode(void); - #define __HAVE_ARCH_ENTER_LAZY_MMU_MODE static inline void arch_enter_lazy_mmu_mode(void) { diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index 8ab250ac498b..5eea9548216b 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -301,19 +301,6 @@ void arch_flush_lazy_mmu_mode(void) preempt_enable(); } -void arch_flush_lazy_cpu_mode(void) -{ - preempt_disable(); - - if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_CPU) { - WARN_ON(preempt_count() == 1); - arch_leave_lazy_cpu_mode(); - arch_enter_lazy_cpu_mode(); - } - - preempt_enable(); -} - struct pv_info pv_info = { .name = "bare hardware", .paravirt_enabled = 0, diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 14014d766cad..57e49a8278a9 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -407,7 +407,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) * done before math_state_restore, so the TS bit is up * to date. */ - arch_leave_lazy_cpu_mode(); + arch_end_context_switch(); /* If the task has used fpu the last 5 timeslices, just do a full * restore of the math state immediately to avoid the trap; the diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index abb7e6a7f0c6..7115e6085326 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -428,7 +428,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) * done before math_state_restore, so the TS bit is up * to date. */ - arch_leave_lazy_cpu_mode(); + arch_end_context_switch(); /* * Switch FS and GS. diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index cb6afa4ec95c..6b98f87232ac 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -1119,10 +1119,8 @@ static void drop_other_mm_ref(void *info) /* If this cpu still has a stale cr3 reference, then make sure it has been flushed. */ - if (percpu_read(xen_current_cr3) == __pa(mm->pgd)) { + if (percpu_read(xen_current_cr3) == __pa(mm->pgd)) load_cr3(swapper_pg_dir); - arch_flush_lazy_cpu_mode(); - } } static void xen_drop_mm_ref(struct mm_struct *mm) @@ -1135,7 +1133,6 @@ static void xen_drop_mm_ref(struct mm_struct *mm) load_cr3(swapper_pg_dir); else leave_mm(smp_processor_id()); - arch_flush_lazy_cpu_mode(); } /* Get the "official" set of cpus referring to our pagetable. */ diff --git a/include/asm-frv/pgtable.h b/include/asm-frv/pgtable.h index e16fdb1f4f4f..235e34a7a340 100644 --- a/include/asm-frv/pgtable.h +++ b/include/asm-frv/pgtable.h @@ -73,8 +73,8 @@ static inline int pte_file(pte_t pte) { return 0; } #define pgtable_cache_init() do {} while (0) #define arch_enter_lazy_mmu_mode() do {} while (0) #define arch_leave_lazy_mmu_mode() do {} while (0) -#define arch_enter_lazy_cpu_mode() do {} while (0) -#define arch_leave_lazy_cpu_mode() do {} while (0) + +#define arch_start_context_switch() do {} while (0) #else /* !CONFIG_MMU */ /*****************************************************************************/ diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index 8e6d0ca70aba..922f03671dd8 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -280,17 +280,18 @@ static inline void ptep_modify_prot_commit(struct mm_struct *mm, #endif /* - * A facility to provide batching of the reload of page tables with the - * actual context switch code for paravirtualized guests. By convention, - * only one of the lazy modes (CPU, MMU) should be active at any given - * time, entry should never be nested, and entry and exits should always - * be paired. This is for sanity of maintaining and reasoning about the - * kernel code. + * A facility to provide batching of the reload of page tables and + * other process state with the actual context switch code for + * paravirtualized guests. By convention, only one of the batched + * update (lazy) modes (CPU, MMU) should be active at any given time, + * entry should never be nested, and entry and exits should always be + * paired. This is for sanity of maintaining and reasoning about the + * kernel code. In this case, the exit (end of the context switch) is + * in architecture-specific code, and so doesn't need a generic + * definition. */ -#ifndef __HAVE_ARCH_ENTER_LAZY_CPU_MODE -#define arch_enter_lazy_cpu_mode() do {} while (0) -#define arch_leave_lazy_cpu_mode() do {} while (0) -#define arch_flush_lazy_cpu_mode() do {} while (0) +#ifndef __HAVE_ARCH_START_CONTEXT_SWITCH +#define arch_start_context_switch() do {} while (0) #endif #ifndef __HAVE_PFNMAP_TRACKING diff --git a/kernel/sched.c b/kernel/sched.c index 5757e03cfac0..7530fdd7c982 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -2746,7 +2746,7 @@ context_switch(struct rq *rq, struct task_struct *prev, * combine the page table reload and the switch backend into * one hypercall. */ - arch_enter_lazy_cpu_mode(); + arch_start_context_switch(); if (unlikely(!mm)) { next->active_mm = oldmm; -- cgit v1.2.3 From b407fc57b815b2016186220baabc76cc8264206e Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Tue, 17 Feb 2009 23:46:21 -0800 Subject: x86/paravirt: flush pending mmu updates on context switch Impact: allow preemption during lazy mmu updates If we're in lazy mmu mode when context switching, leave lazy mmu mode, but remember the task's state in TIF_LAZY_MMU_UPDATES. When we resume the task, check this flag and re-enter lazy mmu mode if its set. This sets things up for allowing lazy mmu mode while preemptible, though that won't actually be active until the next change. Signed-off-by: Jeremy Fitzhardinge Acked-by: Peter Zijlstra --- arch/x86/include/asm/paravirt.h | 1 - arch/x86/include/asm/thread_info.h | 2 ++ arch/x86/kernel/kvm.c | 2 +- arch/x86/kernel/paravirt.c | 13 ++++++++++--- arch/x86/kernel/vmi_32.c | 14 ++++++++++---- arch/x86/lguest/boot.c | 14 ++++++++++---- arch/x86/xen/enlighten.c | 6 +++--- arch/x86/xen/mmu.c | 7 ++++++- arch/x86/xen/xen-ops.h | 1 - 9 files changed, 42 insertions(+), 18 deletions(-) diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index 7b28abac323f..58d2481b01a6 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -1418,7 +1418,6 @@ void paravirt_enter_lazy_cpu(void); void paravirt_leave_lazy_cpu(void); void paravirt_enter_lazy_mmu(void); void paravirt_leave_lazy_mmu(void); -void paravirt_leave_lazy(enum paravirt_lazy_mode mode); #define __HAVE_ARCH_START_CONTEXT_SWITCH static inline void arch_start_context_switch(void) diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index df9d5f78385e..2f34d643b567 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -94,6 +94,7 @@ struct thread_info { #define TIF_FORCED_TF 24 /* true if TF in eflags artificially */ #define TIF_DEBUGCTLMSR 25 /* uses thread_struct.debugctlmsr */ #define TIF_DS_AREA_MSR 26 /* uses thread_struct.ds_area_msr */ +#define TIF_LAZY_MMU_UPDATES 27 /* task is updating the mmu lazily */ #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) @@ -115,6 +116,7 @@ struct thread_info { #define _TIF_FORCED_TF (1 << TIF_FORCED_TF) #define _TIF_DEBUGCTLMSR (1 << TIF_DEBUGCTLMSR) #define _TIF_DS_AREA_MSR (1 << TIF_DS_AREA_MSR) +#define _TIF_LAZY_MMU_UPDATES (1 << TIF_LAZY_MMU_UPDATES) /* work to do in syscall_trace_enter() */ #define _TIF_WORK_SYSCALL_ENTRY \ diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 478bca986eca..5d7f6e76b5dc 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -201,7 +201,7 @@ static void kvm_leave_lazy_mmu(void) struct kvm_para_state *state = kvm_para_state(); mmu_queue_flush(state); - paravirt_leave_lazy(paravirt_get_lazy_mode()); + paravirt_leave_lazy_mmu(); state->mode = paravirt_get_lazy_mode(); } diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index 5eea9548216b..430a0e30577b 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -252,7 +252,7 @@ static inline void enter_lazy(enum paravirt_lazy_mode mode) __get_cpu_var(paravirt_lazy_mode) = mode; } -void paravirt_leave_lazy(enum paravirt_lazy_mode mode) +static void leave_lazy(enum paravirt_lazy_mode mode) { BUG_ON(__get_cpu_var(paravirt_lazy_mode) != mode); BUG_ON(preemptible()); @@ -267,17 +267,24 @@ void paravirt_enter_lazy_mmu(void) void paravirt_leave_lazy_mmu(void) { - paravirt_leave_lazy(PARAVIRT_LAZY_MMU); + leave_lazy(PARAVIRT_LAZY_MMU); } void paravirt_enter_lazy_cpu(void) { + if (percpu_read(paravirt_lazy_mode) == PARAVIRT_LAZY_MMU) { + arch_leave_lazy_mmu_mode(); + set_thread_flag(TIF_LAZY_MMU_UPDATES); + } enter_lazy(PARAVIRT_LAZY_CPU); } void paravirt_leave_lazy_cpu(void) { - paravirt_leave_lazy(PARAVIRT_LAZY_CPU); + leave_lazy(PARAVIRT_LAZY_CPU); + + if (test_and_clear_thread_flag(TIF_LAZY_MMU_UPDATES)) + arch_enter_lazy_mmu_mode(); } enum paravirt_lazy_mode paravirt_get_lazy_mode(void) diff --git a/arch/x86/kernel/vmi_32.c b/arch/x86/kernel/vmi_32.c index 2cc4a90e2cb3..950929c607d3 100644 --- a/arch/x86/kernel/vmi_32.c +++ b/arch/x86/kernel/vmi_32.c @@ -473,16 +473,22 @@ static void vmi_enter_lazy_cpu(void) vmi_ops.set_lazy_mode(2); } +static void vmi_leave_lazy_cpu(void) +{ + vmi_ops.set_lazy_mode(0); + paravirt_leave_lazy_cpu(); +} + static void vmi_enter_lazy_mmu(void) { paravirt_enter_lazy_mmu(); vmi_ops.set_lazy_mode(1); } -static void vmi_leave_lazy(void) +static void vmi_leave_lazy_mmu(void) { - paravirt_leave_lazy(paravirt_get_lazy_mode()); vmi_ops.set_lazy_mode(0); + paravirt_leave_lazy_mmu(); } static inline int __init check_vmi_rom(struct vrom_header *rom) @@ -718,12 +724,12 @@ static inline int __init activate_vmi(void) para_wrap(pv_cpu_ops.lazy_mode.enter, vmi_enter_lazy_cpu, set_lazy_mode, SetLazyMode); - para_wrap(pv_cpu_ops.lazy_mode.leave, vmi_leave_lazy, + para_wrap(pv_cpu_ops.lazy_mode.leave, vmi_leave_lazy_cpu, set_lazy_mode, SetLazyMode); para_wrap(pv_mmu_ops.lazy_mode.enter, vmi_enter_lazy_mmu, set_lazy_mode, SetLazyMode); - para_wrap(pv_mmu_ops.lazy_mode.leave, vmi_leave_lazy, + para_wrap(pv_mmu_ops.lazy_mode.leave, vmi_leave_lazy_mmu, set_lazy_mode, SetLazyMode); /* user and kernel flush are just handled with different flags to FlushTLB */ diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c index 9fe4ddaa8f6f..41a5562e710e 100644 --- a/arch/x86/lguest/boot.c +++ b/arch/x86/lguest/boot.c @@ -147,10 +147,16 @@ static void lazy_hcall(unsigned long call, /* When lazy mode is turned off reset the per-cpu lazy mode variable and then * issue the do-nothing hypercall to flush any stored calls. */ -static void lguest_leave_lazy_mode(void) +static void lguest_leave_lazy_mmu_mode(void) { - paravirt_leave_lazy(paravirt_get_lazy_mode()); hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0); + paravirt_leave_lazy_mmu(); +} + +static void lguest_leave_lazy_cpu_mode(void) +{ + hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0); + paravirt_leave_lazy_cpu(); } /*G:033 @@ -1026,7 +1032,7 @@ __init void lguest_init(void) pv_cpu_ops.write_idt_entry = lguest_write_idt_entry; pv_cpu_ops.wbinvd = lguest_wbinvd; pv_cpu_ops.lazy_mode.enter = paravirt_enter_lazy_cpu; - pv_cpu_ops.lazy_mode.leave = lguest_leave_lazy_mode; + pv_cpu_ops.lazy_mode.leave = lguest_leave_lazy_cpu_mode; /* pagetable management */ pv_mmu_ops.write_cr3 = lguest_write_cr3; @@ -1039,7 +1045,7 @@ __init void lguest_init(void) pv_mmu_ops.read_cr2 = lguest_read_cr2; pv_mmu_ops.read_cr3 = lguest_read_cr3; pv_mmu_ops.lazy_mode.enter = paravirt_enter_lazy_mmu; - pv_mmu_ops.lazy_mode.leave = lguest_leave_lazy_mode; + pv_mmu_ops.lazy_mode.leave = lguest_leave_lazy_mmu_mode; #ifdef CONFIG_X86_LOCAL_APIC /* apic read/write intercepts */ diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 82cd39a6cbd3..f586e63b9a63 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -203,10 +203,10 @@ static unsigned long xen_get_debugreg(int reg) return HYPERVISOR_get_debugreg(reg); } -void xen_leave_lazy(void) +static void xen_leave_lazy_cpu(void) { - paravirt_leave_lazy(paravirt_get_lazy_mode()); xen_mc_flush(); + paravirt_leave_lazy_cpu(); } static unsigned long xen_store_tr(void) @@ -819,7 +819,7 @@ static const struct pv_cpu_ops xen_cpu_ops __initdata = { .lazy_mode = { .enter = paravirt_enter_lazy_cpu, - .leave = xen_leave_lazy, + .leave = xen_leave_lazy_cpu, }, }; diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 6b98f87232ac..f5f8faa4f76c 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -1816,6 +1816,11 @@ __init void xen_post_allocator_init(void) xen_mark_init_mm_pinned(); } +static void xen_leave_lazy_mmu(void) +{ + xen_mc_flush(); + paravirt_leave_lazy_mmu(); +} const struct pv_mmu_ops xen_mmu_ops __initdata = { .pagetable_setup_start = xen_pagetable_setup_start, @@ -1891,7 +1896,7 @@ const struct pv_mmu_ops xen_mmu_ops __initdata = { .lazy_mode = { .enter = paravirt_enter_lazy_mmu, - .leave = xen_leave_lazy, + .leave = xen_leave_lazy_mmu, }, .set_fixmap = xen_set_fixmap, diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h index 2f5ef2632ea2..f897cdffccb6 100644 --- a/arch/x86/xen/xen-ops.h +++ b/arch/x86/xen/xen-ops.h @@ -30,7 +30,6 @@ pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd, unsigned long max_pfn); void xen_ident_map_ISA(void); void xen_reserve_top(void); -void xen_leave_lazy(void); void xen_post_allocator_init(void); char * __init xen_memory_setup(void); -- cgit v1.2.3 From 224101ed69d3fbb486868e0f6e0f9fa37302efb4 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Wed, 18 Feb 2009 11:18:57 -0800 Subject: x86/paravirt: finish change from lazy cpu to context switch start/end Impact: fix lazy context switch API Pass the previous and next tasks into the context switch start end calls, so that the called functions can properly access the task state (esp in end_context_switch, in which the next task is not yet completely current). Signed-off-by: Jeremy Fitzhardinge Acked-by: Peter Zijlstra --- arch/x86/include/asm/paravirt.h | 17 ++++++++++------- arch/x86/include/asm/pgtable.h | 2 ++ arch/x86/kernel/paravirt.c | 14 ++++++-------- arch/x86/kernel/process_32.c | 2 +- arch/x86/kernel/process_64.c | 2 +- arch/x86/kernel/vmi_32.c | 12 ++++++------ arch/x86/lguest/boot.c | 8 ++++---- arch/x86/xen/enlighten.c | 10 ++++------ include/asm-frv/pgtable.h | 2 +- include/asm-generic/pgtable.h | 2 +- kernel/sched.c | 2 +- 11 files changed, 37 insertions(+), 36 deletions(-) diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index 58d2481b01a6..dfdee0ca57d3 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -56,6 +56,7 @@ struct desc_ptr; struct tss_struct; struct mm_struct; struct desc_struct; +struct task_struct; /* * Wrapper type for pointers to code which uses the non-standard @@ -203,7 +204,8 @@ struct pv_cpu_ops { void (*swapgs)(void); - struct pv_lazy_ops lazy_mode; + void (*start_context_switch)(struct task_struct *prev); + void (*end_context_switch)(struct task_struct *next); }; struct pv_irq_ops { @@ -1414,20 +1416,21 @@ enum paravirt_lazy_mode { }; enum paravirt_lazy_mode paravirt_get_lazy_mode(void); -void paravirt_enter_lazy_cpu(void); -void paravirt_leave_lazy_cpu(void); +void paravirt_start_context_switch(struct task_struct *prev); +void paravirt_end_context_switch(struct task_struct *next); + void paravirt_enter_lazy_mmu(void); void paravirt_leave_lazy_mmu(void); #define __HAVE_ARCH_START_CONTEXT_SWITCH -static inline void arch_start_context_switch(void) +static inline void arch_start_context_switch(struct task_struct *prev) { - PVOP_VCALL0(pv_cpu_ops.lazy_mode.enter); + PVOP_VCALL1(pv_cpu_ops.start_context_switch, prev); } -static inline void arch_end_context_switch(void) +static inline void arch_end_context_switch(struct task_struct *next) { - PVOP_VCALL0(pv_cpu_ops.lazy_mode.leave); + PVOP_VCALL1(pv_cpu_ops.end_context_switch, next); } #define __HAVE_ARCH_ENTER_LAZY_MMU_MODE diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index d0812e155f1d..24e42836e921 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -83,6 +83,8 @@ static inline void __init paravirt_pagetable_setup_done(pgd_t *base) #define pte_val(x) native_pte_val(x) #define __pte(x) native_make_pte(x) +#define arch_end_context_switch(prev) do {} while(0) + #endif /* CONFIG_PARAVIRT */ /* diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index 430a0e30577b..cf1437503bab 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -270,20 +270,20 @@ void paravirt_leave_lazy_mmu(void) leave_lazy(PARAVIRT_LAZY_MMU); } -void paravirt_enter_lazy_cpu(void) +void paravirt_start_context_switch(struct task_struct *prev) { if (percpu_read(paravirt_lazy_mode) == PARAVIRT_LAZY_MMU) { arch_leave_lazy_mmu_mode(); - set_thread_flag(TIF_LAZY_MMU_UPDATES); + set_ti_thread_flag(task_thread_info(prev), TIF_LAZY_MMU_UPDATES); } enter_lazy(PARAVIRT_LAZY_CPU); } -void paravirt_leave_lazy_cpu(void) +void paravirt_end_context_switch(struct task_struct *next) { leave_lazy(PARAVIRT_LAZY_CPU); - if (test_and_clear_thread_flag(TIF_LAZY_MMU_UPDATES)) + if (test_and_clear_ti_thread_flag(task_thread_info(next), TIF_LAZY_MMU_UPDATES)) arch_enter_lazy_mmu_mode(); } @@ -399,10 +399,8 @@ struct pv_cpu_ops pv_cpu_ops = { .set_iopl_mask = native_set_iopl_mask, .io_delay = native_io_delay, - .lazy_mode = { - .enter = paravirt_nop, - .leave = paravirt_nop, - }, + .start_context_switch = paravirt_nop, + .end_context_switch = paravirt_nop, }; struct pv_apic_ops pv_apic_ops = { diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 57e49a8278a9..d766c7616fd7 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -407,7 +407,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) * done before math_state_restore, so the TS bit is up * to date. */ - arch_end_context_switch(); + arch_end_context_switch(next_p); /* If the task has used fpu the last 5 timeslices, just do a full * restore of the math state immediately to avoid the trap; the diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 7115e6085326..e8a9aaf9df88 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -428,7 +428,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) * done before math_state_restore, so the TS bit is up * to date. */ - arch_end_context_switch(); + arch_end_context_switch(next_p); /* * Switch FS and GS. diff --git a/arch/x86/kernel/vmi_32.c b/arch/x86/kernel/vmi_32.c index 950929c607d3..55a5d6938e5e 100644 --- a/arch/x86/kernel/vmi_32.c +++ b/arch/x86/kernel/vmi_32.c @@ -467,16 +467,16 @@ vmi_startup_ipi_hook(int phys_apicid, unsigned long start_eip, } #endif -static void vmi_enter_lazy_cpu(void) +static void vmi_start_context_switch(struct task_struct *prev) { - paravirt_enter_lazy_cpu(); + paravirt_start_context_switch(prev); vmi_ops.set_lazy_mode(2); } -static void vmi_leave_lazy_cpu(void) +static void vmi_end_context_switch(struct task_struct *next) { vmi_ops.set_lazy_mode(0); - paravirt_leave_lazy_cpu(); + paravirt_end_context_switch(next); } static void vmi_enter_lazy_mmu(void) @@ -722,9 +722,9 @@ static inline int __init activate_vmi(void) para_fill(pv_cpu_ops.set_iopl_mask, SetIOPLMask); para_fill(pv_cpu_ops.io_delay, IODelay); - para_wrap(pv_cpu_ops.lazy_mode.enter, vmi_enter_lazy_cpu, + para_wrap(pv_cpu_ops.start_context_switch, vmi_start_context_switch, set_lazy_mode, SetLazyMode); - para_wrap(pv_cpu_ops.lazy_mode.leave, vmi_leave_lazy_cpu, + para_wrap(pv_cpu_ops.end_context_switch, vmi_end_context_switch, set_lazy_mode, SetLazyMode); para_wrap(pv_mmu_ops.lazy_mode.enter, vmi_enter_lazy_mmu, diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c index 41a5562e710e..5287081b3567 100644 --- a/arch/x86/lguest/boot.c +++ b/arch/x86/lguest/boot.c @@ -153,10 +153,10 @@ static void lguest_leave_lazy_mmu_mode(void) paravirt_leave_lazy_mmu(); } -static void lguest_leave_lazy_cpu_mode(void) +static void lguest_end_context_switch(struct task_struct *next) { hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0); - paravirt_leave_lazy_cpu(); + paravirt_end_context_switch(next); } /*G:033 @@ -1031,8 +1031,8 @@ __init void lguest_init(void) pv_cpu_ops.write_gdt_entry = lguest_write_gdt_entry; pv_cpu_ops.write_idt_entry = lguest_write_idt_entry; pv_cpu_ops.wbinvd = lguest_wbinvd; - pv_cpu_ops.lazy_mode.enter = paravirt_enter_lazy_cpu; - pv_cpu_ops.lazy_mode.leave = lguest_leave_lazy_cpu_mode; + pv_cpu_ops.start_context_switch = paravirt_start_context_switch; + pv_cpu_ops.end_context_switch = lguest_end_context_switch; /* pagetable management */ pv_mmu_ops.write_cr3 = lguest_write_cr3; diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index f586e63b9a63..70b355d3a86c 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -203,10 +203,10 @@ static unsigned long xen_get_debugreg(int reg) return HYPERVISOR_get_debugreg(reg); } -static void xen_leave_lazy_cpu(void) +static void xen_end_context_switch(struct task_struct *next) { xen_mc_flush(); - paravirt_leave_lazy_cpu(); + paravirt_end_context_switch(next); } static unsigned long xen_store_tr(void) @@ -817,10 +817,8 @@ static const struct pv_cpu_ops xen_cpu_ops __initdata = { /* Xen takes care of %gs when switching to usermode for us */ .swapgs = paravirt_nop, - .lazy_mode = { - .enter = paravirt_enter_lazy_cpu, - .leave = xen_leave_lazy_cpu, - }, + .start_context_switch = paravirt_start_context_switch, + .end_context_switch = xen_end_context_switch, }; static const struct pv_apic_ops xen_apic_ops __initdata = { diff --git a/include/asm-frv/pgtable.h b/include/asm-frv/pgtable.h index 235e34a7a340..09887045d03f 100644 --- a/include/asm-frv/pgtable.h +++ b/include/asm-frv/pgtable.h @@ -74,7 +74,7 @@ static inline int pte_file(pte_t pte) { return 0; } #define arch_enter_lazy_mmu_mode() do {} while (0) #define arch_leave_lazy_mmu_mode() do {} while (0) -#define arch_start_context_switch() do {} while (0) +#define arch_start_context_switch(prev) do {} while (0) #else /* !CONFIG_MMU */ /*****************************************************************************/ diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index 922f03671dd8..e410f602cab1 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -291,7 +291,7 @@ static inline void ptep_modify_prot_commit(struct mm_struct *mm, * definition. */ #ifndef __HAVE_ARCH_START_CONTEXT_SWITCH -#define arch_start_context_switch() do {} while (0) +#define arch_start_context_switch(prev) do {} while (0) #endif #ifndef __HAVE_PFNMAP_TRACKING diff --git a/kernel/sched.c b/kernel/sched.c index 7530fdd7c982..133762aece50 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -2746,7 +2746,7 @@ context_switch(struct rq *rq, struct task_struct *prev, * combine the page table reload and the switch backend into * one hypercall. */ - arch_start_context_switch(); + arch_start_context_switch(prev); if (unlikely(!mm)) { next->active_mm = oldmm; -- cgit v1.2.3 From 2829b449276aed45f3d649efb21e3418e39dd5d1 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Tue, 17 Feb 2009 23:53:19 -0800 Subject: x86/paravirt: allow preemption with lazy mmu mode Impact: remove obsolete checks, simplification Lift restrictions on preemption with lazy mmu mode, as it is now allowed. Signed-off-by: Jeremy Fitzhardinge Acked-by: Peter Zijlstra --- arch/x86/kernel/paravirt.c | 7 ++++--- arch/x86/xen/mmu.c | 8 +------- 2 files changed, 5 insertions(+), 10 deletions(-) diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index cf1437503bab..bf2e86eee80c 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -247,7 +247,6 @@ static DEFINE_PER_CPU(enum paravirt_lazy_mode, paravirt_lazy_mode) = PARAVIRT_LA static inline void enter_lazy(enum paravirt_lazy_mode mode) { BUG_ON(__get_cpu_var(paravirt_lazy_mode) != PARAVIRT_LAZY_NONE); - BUG_ON(preemptible()); __get_cpu_var(paravirt_lazy_mode) = mode; } @@ -255,7 +254,6 @@ static inline void enter_lazy(enum paravirt_lazy_mode mode) static void leave_lazy(enum paravirt_lazy_mode mode) { BUG_ON(__get_cpu_var(paravirt_lazy_mode) != mode); - BUG_ON(preemptible()); __get_cpu_var(paravirt_lazy_mode) = PARAVIRT_LAZY_NONE; } @@ -272,6 +270,8 @@ void paravirt_leave_lazy_mmu(void) void paravirt_start_context_switch(struct task_struct *prev) { + BUG_ON(preemptible()); + if (percpu_read(paravirt_lazy_mode) == PARAVIRT_LAZY_MMU) { arch_leave_lazy_mmu_mode(); set_ti_thread_flag(task_thread_info(prev), TIF_LAZY_MMU_UPDATES); @@ -281,6 +281,8 @@ void paravirt_start_context_switch(struct task_struct *prev) void paravirt_end_context_switch(struct task_struct *next) { + BUG_ON(preemptible()); + leave_lazy(PARAVIRT_LAZY_CPU); if (test_and_clear_ti_thread_flag(task_thread_info(next), TIF_LAZY_MMU_UPDATES)) @@ -300,7 +302,6 @@ void arch_flush_lazy_mmu_mode(void) preempt_disable(); if (paravirt_get_lazy_mode() == PARAVIRT_LAZY_MMU) { - WARN_ON(preempt_count() == 1); arch_leave_lazy_mmu_mode(); arch_enter_lazy_mmu_mode(); } diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index f5f8faa4f76c..3f2d0fe5e6a8 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -419,10 +419,6 @@ void set_pte_mfn(unsigned long vaddr, unsigned long mfn, pgprot_t flags) void xen_set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pteval) { - /* updates to init_mm may be done without lock */ - if (mm == &init_mm) - preempt_disable(); - ADD_STATS(set_pte_at, 1); // ADD_STATS(set_pte_at_pinned, xen_page_pinned(ptep)); ADD_STATS(set_pte_at_current, mm == current->mm); @@ -443,9 +439,7 @@ void xen_set_pte_at(struct mm_struct *mm, unsigned long addr, } xen_set_pte(ptep, pteval); -out: - if (mm == &init_mm) - preempt_enable(); +out: return; } pte_t xen_ptep_modify_prot_start(struct mm_struct *mm, -- cgit v1.2.3 From 252a6bf2a3a7e7add56b17d48aecf3f3ef213103 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Wed, 18 Feb 2009 00:11:28 -0800 Subject: mm: allow preemption in apply_to_pte_range Impact: allow preemption in apply_to_pte_range updates to init_mm Preemption is now allowed for lazy mmu mode, so don't disable it for the inner loop of apply_to_pte_range. This only applies when doing updates to init_mm; user pagetables are still modified under the pte lock, so preemption is disabled anyway. Signed-off-by: Jeremy Fitzhardinge Acked-by: Peter Zijlstra --- mm/memory.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index b80cc31292b1..baa999e87cd2 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1718,7 +1718,6 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, BUG_ON(pmd_huge(*pmd)); - preempt_disable(); arch_enter_lazy_mmu_mode(); token = pmd_pgtable(*pmd); @@ -1730,7 +1729,6 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, } while (pte++, addr += PAGE_SIZE, addr != end); arch_leave_lazy_mmu_mode(); - preempt_enable(); if (mm != &init_mm) pte_unmap_unlock(pte-1, ptl); -- cgit v1.2.3 From ab2f75f0b760d2b0c9a875b669a1b51dce02c85a Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Wed, 18 Feb 2009 00:18:50 -0800 Subject: x86/paravirt: use percpu_ rather than __get_cpu_var Impact: minor optimisation percpu_read/write is a slightly more direct way of getting to percpu data. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/kernel/paravirt.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index bf2e86eee80c..254e8aa8bfdb 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -246,16 +246,16 @@ static DEFINE_PER_CPU(enum paravirt_lazy_mode, paravirt_lazy_mode) = PARAVIRT_LA static inline void enter_lazy(enum paravirt_lazy_mode mode) { - BUG_ON(__get_cpu_var(paravirt_lazy_mode) != PARAVIRT_LAZY_NONE); + BUG_ON(percpu_read(paravirt_lazy_mode) != PARAVIRT_LAZY_NONE); - __get_cpu_var(paravirt_lazy_mode) = mode; + percpu_write(paravirt_lazy_mode, mode); } static void leave_lazy(enum paravirt_lazy_mode mode) { - BUG_ON(__get_cpu_var(paravirt_lazy_mode) != mode); + BUG_ON(percpu_read(paravirt_lazy_mode) != mode); - __get_cpu_var(paravirt_lazy_mode) = PARAVIRT_LAZY_NONE; + percpu_write(paravirt_lazy_mode, PARAVIRT_LAZY_NONE); } void paravirt_enter_lazy_mmu(void) @@ -294,7 +294,7 @@ enum paravirt_lazy_mode paravirt_get_lazy_mode(void) if (in_interrupt()) return PARAVIRT_LAZY_NONE; - return __get_cpu_var(paravirt_lazy_mode); + return percpu_read(paravirt_lazy_mode); } void arch_flush_lazy_mmu_mode(void) -- cgit v1.2.3 From 5caecb9432428241d0c641897f07ff4003f1b55f Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Fri, 20 Feb 2009 23:01:26 -0800 Subject: xen: disable preempt for leave_lazy_mmu xen_mc_flush() requires preemption to be disabled for its own sanity, so disable it while we're flushing. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/mmu.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 3f2d0fe5e6a8..0e572380413b 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -1812,8 +1812,10 @@ __init void xen_post_allocator_init(void) static void xen_leave_lazy_mmu(void) { + preempt_disable(); xen_mc_flush(); paravirt_leave_lazy_mmu(); + preempt_enable(); } const struct pv_mmu_ops xen_mmu_ops __initdata = { -- cgit v1.2.3 From 59d7187142bbe9b404a403ed0f874d3227305f26 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Thu, 26 Feb 2009 15:48:33 -0800 Subject: xen: separate p2m allocation from setting When doing very early p2m setting, we need to separate setting from allocation, so split things up accordingly. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/mmu.c | 61 +++++++++++++++++++++++++++++++++++++++--------------- arch/x86/xen/mmu.h | 3 +++ 2 files changed, 47 insertions(+), 17 deletions(-) diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 0e572380413b..e0a55b7a6ceb 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -233,47 +233,74 @@ unsigned long get_phys_to_machine(unsigned long pfn) } EXPORT_SYMBOL_GPL(get_phys_to_machine); -static void alloc_p2m(unsigned long **pp, unsigned long *mfnp) +/* install a new p2m_top page */ +bool install_p2mtop_page(unsigned long pfn, unsigned long *p) { - unsigned long *p; + unsigned topidx = p2m_top_index(pfn); + unsigned long **pfnp, *mfnp; unsigned i; - p = (void *)__get_free_page(GFP_KERNEL | __GFP_NOFAIL); - BUG_ON(p == NULL); + pfnp = &p2m_top[topidx]; + mfnp = &p2m_top_mfn[topidx]; for (i = 0; i < P2M_ENTRIES_PER_PAGE; i++) p[i] = INVALID_P2M_ENTRY; - if (cmpxchg(pp, p2m_missing, p) != p2m_missing) - free_page((unsigned long)p); - else + if (cmpxchg(pfnp, p2m_missing, p) == p2m_missing) { *mfnp = virt_to_mfn(p); + return true; + } + + return false; } -void set_phys_to_machine(unsigned long pfn, unsigned long mfn) +static void alloc_p2m(unsigned long pfn) { - unsigned topidx, idx; + unsigned long *p; - if (unlikely(xen_feature(XENFEAT_auto_translated_physmap))) { - BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY); - return; - } + p = (void *)__get_free_page(GFP_KERNEL | __GFP_NOFAIL); + BUG_ON(p == NULL); + + if (!install_p2mtop_page(pfn, p)) + free_page((unsigned long)p); +} + +/* Try to install p2m mapping; fail if intermediate bits missing */ +bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn) +{ + unsigned topidx, idx; if (unlikely(pfn >= MAX_DOMAIN_PAGES)) { BUG_ON(mfn != INVALID_P2M_ENTRY); - return; + return true; } topidx = p2m_top_index(pfn); if (p2m_top[topidx] == p2m_missing) { - /* no need to allocate a page to store an invalid entry */ if (mfn == INVALID_P2M_ENTRY) - return; - alloc_p2m(&p2m_top[topidx], &p2m_top_mfn[topidx]); + return true; + return false; } idx = p2m_index(pfn); p2m_top[topidx][idx] = mfn; + + return true; +} + +void set_phys_to_machine(unsigned long pfn, unsigned long mfn) +{ + if (unlikely(xen_feature(XENFEAT_auto_translated_physmap))) { + BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY); + return; + } + + if (unlikely(!__set_phys_to_machine(pfn, mfn))) { + alloc_p2m(pfn); + + if (!__set_phys_to_machine(pfn, mfn)) + BUG(); + } } unsigned long arbitrary_virt_to_mfn(void *vaddr) diff --git a/arch/x86/xen/mmu.h b/arch/x86/xen/mmu.h index 24d1b44a337d..da7302624897 100644 --- a/arch/x86/xen/mmu.h +++ b/arch/x86/xen/mmu.h @@ -11,6 +11,9 @@ enum pt_level { }; +bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn); +bool install_p2mtop_page(unsigned long pfn, unsigned long *p); + void set_pte_mfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags); -- cgit v1.2.3 From 7571a60446030d2576d881438447e86a0755a83b Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Fri, 27 Feb 2009 15:34:59 -0800 Subject: xen: split construction of p2m mfn tables from registration Build the p2m_mfn_list_list early with the rest of the p2m table, but register it later when the real shared_info structure is in place. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/mmu.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index e0a55b7a6ceb..67d2ab45cd90 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -184,7 +184,7 @@ static inline unsigned p2m_index(unsigned long pfn) } /* Build the parallel p2m_top_mfn structures */ -void xen_setup_mfn_list_list(void) +static void __init xen_build_mfn_list_list(void) { unsigned pfn, idx; @@ -198,7 +198,10 @@ void xen_setup_mfn_list_list(void) unsigned topidx = idx * P2M_ENTRIES_PER_PAGE; p2m_top_mfn_list[idx] = virt_to_mfn(&p2m_top_mfn[topidx]); } +} +void xen_setup_mfn_list_list(void) +{ BUG_ON(HYPERVISOR_shared_info == &xen_dummy_shared_info); HYPERVISOR_shared_info->arch.pfn_to_mfn_frame_list_list = @@ -218,6 +221,8 @@ void __init xen_build_dynamic_phys_to_machine(void) p2m_top[topidx] = &mfn_list[pfn]; } + + xen_build_mfn_list_list(); } unsigned long get_phys_to_machine(unsigned long pfn) -- cgit v1.2.3 From 6ed6bf428aff64fe37cdc54b239d598fee6016f1 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Wed, 4 Mar 2009 13:02:18 -0800 Subject: xen: clean up xen_load_gdt Makes the logic a bit clearer. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/enlighten.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 70b355d3a86c..5776dc270297 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -301,10 +301,21 @@ static void xen_load_gdt(const struct desc_ptr *dtr) frames = mcs.args; for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) { - frames[f] = arbitrary_virt_to_mfn((void *)va); + int level; + pte_t *ptep = lookup_address(va, &level); + unsigned long pfn, mfn; + void *virt; + + BUG_ON(ptep == NULL); + + pfn = pte_pfn(*ptep); + mfn = pfn_to_mfn(pfn); + virt = __va(PFN_PHYS(pfn)); + + frames[f] = mfn; make_lowmem_page_readonly((void *)va); - make_lowmem_page_readonly(mfn_to_virt(frames[f])); + make_lowmem_page_readonly(virt); } MULTI_set_gdt(mcs.mc, frames, size / sizeof(struct desc_struct)); -- cgit v1.2.3 From 3ce5fa7ebff74b6a4dc5fdcdc22e6979f5a4ff85 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Wed, 4 Mar 2009 15:26:00 -0800 Subject: xen: make xen_load_gdt simpler Remove use of multicall machinery which is unused (gdt loading is never performance critical). This removes the implicit use of percpu variables, which simplifies understanding how the percpu code's use of load_gdt interacts with this code. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/enlighten.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 5776dc270297..48b399bd6e0d 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -284,12 +284,11 @@ static void xen_set_ldt(const void *addr, unsigned entries) static void xen_load_gdt(const struct desc_ptr *dtr) { - unsigned long *frames; unsigned long va = dtr->address; unsigned int size = dtr->size + 1; unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE; + unsigned long frames[pages]; int f; - struct multicall_space mcs; /* A GDT can be up to 64k in size, which corresponds to 8192 8-byte entries, or 16 4k pages.. */ @@ -297,9 +296,6 @@ static void xen_load_gdt(const struct desc_ptr *dtr) BUG_ON(size > 65536); BUG_ON(va & ~PAGE_MASK); - mcs = xen_mc_entry(sizeof(*frames) * pages); - frames = mcs.args; - for (f = 0; va < dtr->address + size; va += PAGE_SIZE, f++) { int level; pte_t *ptep = lookup_address(va, &level); @@ -314,13 +310,15 @@ static void xen_load_gdt(const struct desc_ptr *dtr) frames[f] = mfn; + printk("xen_load_gdt: %d va=%p mfn=%lx pfn=%lx va'=%p\n", + f, (void *)va, mfn, pfn, virt); + make_lowmem_page_readonly((void *)va); make_lowmem_page_readonly(virt); } - MULTI_set_gdt(mcs.mc, frames, size / sizeof(struct desc_struct)); - - xen_mc_issue(PARAVIRT_LAZY_CPU); + if (HYPERVISOR_set_gdt(frames, size / sizeof(struct desc_struct))) + BUG(); } static void load_TLS_descriptor(struct thread_struct *t, -- cgit v1.2.3 From b4b7e58590d0e94ed78bd6be1aa163caba7b6c74 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Wed, 4 Mar 2009 16:34:27 -0800 Subject: xen: remove xen_load_gdt debug Don't need the noise. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/enlighten.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 48b399bd6e0d..75b7a0f90380 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -310,9 +310,6 @@ static void xen_load_gdt(const struct desc_ptr *dtr) frames[f] = mfn; - printk("xen_load_gdt: %d va=%p mfn=%lx pfn=%lx va'=%p\n", - f, (void *)va, mfn, pfn, virt); - make_lowmem_page_readonly((void *)va); make_lowmem_page_readonly(virt); } -- cgit v1.2.3 From e9e2d1ffcfdb38bed11a3064aa74bea9ee38ed80 Mon Sep 17 00:00:00 2001 From: Hannes Eder Date: Thu, 5 Mar 2009 20:13:57 +0100 Subject: NULL noise: arch/x86/xen/smp.c Fix this sparse warnings: arch/x86/xen/smp.c:316:52: warning: Using plain integer as NULL pointer arch/x86/xen/smp.c:421:60: warning: Using plain integer as NULL pointer Signed-off-by: Hannes Eder Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/smp.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index 8d470562ffc9..304d832710cd 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -317,7 +317,7 @@ static int __cpuinit xen_cpu_up(unsigned int cpu) BUG_ON(rc); while(per_cpu(cpu_state, cpu) != CPU_ONLINE) { - HYPERVISOR_sched_op(SCHEDOP_yield, 0); + HYPERVISOR_sched_op(SCHEDOP_yield, NULL); barrier(); } @@ -422,7 +422,7 @@ static void xen_smp_send_call_function_ipi(const struct cpumask *mask) /* Make sure other vcpus get a chance to run if they need to. */ for_each_cpu(cpu, mask) { if (xen_vcpu_stolen(cpu)) { - HYPERVISOR_sched_op(SCHEDOP_yield, 0); + HYPERVISOR_sched_op(SCHEDOP_yield, NULL); break; } } -- cgit v1.2.3 From e826fe1ba1563a9272345da8e3279a930ac160a7 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Sat, 7 Mar 2009 17:09:27 -0800 Subject: xen: mask XSAVE from cpuid Xen leaves XSAVE set in cpuid, but doesn't allow cr4.OSXSAVE to be set. This confuses the kernel and it ends up crashing on an xsetbv instruction. At boot time, try to set cr4.OSXSAVE, and mask XSAVE out of cpuid it we can't. This will produce a spurious error from Xen, but allows us to support XSAVE if/when Xen does. This also factors out the cpuid mask decisions to boot time. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/enlighten.c | 50 ++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 44 insertions(+), 6 deletions(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 75b7a0f90380..da33e0c5870d 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -168,21 +168,23 @@ static void __init xen_banner(void) xen_feature(XENFEAT_mmu_pt_update_preserve_ad) ? " (preserve-AD)" : ""); } +static __read_mostly unsigned int cpuid_leaf1_edx_mask = ~0; +static __read_mostly unsigned int cpuid_leaf1_ecx_mask = ~0; + static void xen_cpuid(unsigned int *ax, unsigned int *bx, unsigned int *cx, unsigned int *dx) { + unsigned maskecx = ~0; unsigned maskedx = ~0; /* * Mask out inconvenient features, to try and disable as many * unsupported kernel subsystems as possible. */ - if (*ax == 1) - maskedx = ~((1 << X86_FEATURE_APIC) | /* disable APIC */ - (1 << X86_FEATURE_ACPI) | /* disable ACPI */ - (1 << X86_FEATURE_MCE) | /* disable MCE */ - (1 << X86_FEATURE_MCA) | /* disable MCA */ - (1 << X86_FEATURE_ACC)); /* thermal monitoring */ + if (*ax == 1) { + maskecx = cpuid_leaf1_ecx_mask; + maskedx = cpuid_leaf1_edx_mask; + } asm(XEN_EMULATE_PREFIX "cpuid" : "=a" (*ax), @@ -190,9 +192,43 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx, "=c" (*cx), "=d" (*dx) : "0" (*ax), "2" (*cx)); + + *cx &= maskecx; *dx &= maskedx; } +static __init void xen_init_cpuid_mask(void) +{ + unsigned int ax, bx, cx, dx; + + cpuid_leaf1_edx_mask = + ~((1 << X86_FEATURE_MCE) | /* disable MCE */ + (1 << X86_FEATURE_MCA) | /* disable MCA */ + (1 << X86_FEATURE_ACC)); /* thermal monitoring */ + + if (!xen_initial_domain()) + cpuid_leaf1_edx_mask &= + ~((1 << X86_FEATURE_APIC) | /* disable local APIC */ + (1 << X86_FEATURE_ACPI)); /* disable ACPI */ + + ax = 1; + xen_cpuid(&ax, &bx, &cx, &dx); + + /* cpuid claims we support xsave; try enabling it to see what happens */ + if (cx & (1 << (X86_FEATURE_XSAVE % 32))) { + unsigned long cr4; + + set_in_cr4(X86_CR4_OSXSAVE); + + cr4 = read_cr4(); + + if ((cr4 & X86_CR4_OSXSAVE) == 0) + cpuid_leaf1_ecx_mask &= ~(1 << (X86_FEATURE_XSAVE % 32)); + + clear_in_cr4(X86_CR4_OSXSAVE); + } +} + static void xen_set_debugreg(int reg, unsigned long val) { HYPERVISOR_set_debugreg(reg, val); @@ -901,6 +937,8 @@ asmlinkage void __init xen_start_kernel(void) xen_init_irq_ops(); + xen_init_cpuid_mask(); + #ifdef CONFIG_X86_LOCAL_APIC /* * set up the basic apic ops. -- cgit v1.2.3 From 68509cdcde6583ee1a9542899d1270449c7d5903 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Sun, 8 Mar 2009 03:59:04 -0700 Subject: x86-64: remove PGE from must-have feature list PGE may not be available when running paravirtualized, so test the cpuid bit before using it. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/include/asm/required-features.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/include/asm/required-features.h b/arch/x86/include/asm/required-features.h index d5cd6c586881..a4737dddfd58 100644 --- a/arch/x86/include/asm/required-features.h +++ b/arch/x86/include/asm/required-features.h @@ -50,7 +50,7 @@ #ifdef CONFIG_X86_64 #define NEED_PSE 0 #define NEED_MSR (1<<(X86_FEATURE_MSR & 31)) -#define NEED_PGE (1<<(X86_FEATURE_PGE & 31)) +#define NEED_PGE 0 #define NEED_FXSR (1<<(X86_FEATURE_FXSR & 31)) #define NEED_XMM (1<<(X86_FEATURE_XMM & 31)) #define NEED_XMM2 (1<<(X86_FEATURE_XMM2 & 31)) -- cgit v1.2.3 From 1e7449730853e7c9ae9a2458b2ced7ba12559a0e Mon Sep 17 00:00:00 2001 From: Alex Nixon Date: Mon, 9 Feb 2009 12:05:46 -0800 Subject: Xen: Add virt_to_pfn helper function Signed-off-by: Alex Nixon --- arch/x86/include/asm/xen/page.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/xen/page.h b/arch/x86/include/asm/xen/page.h index 1a918dde46b5..018a0a400799 100644 --- a/arch/x86/include/asm/xen/page.h +++ b/arch/x86/include/asm/xen/page.h @@ -124,7 +124,8 @@ static inline unsigned long mfn_to_local_pfn(unsigned long mfn) /* VIRT <-> MACHINE conversion */ #define virt_to_machine(v) (phys_to_machine(XPADDR(__pa(v)))) -#define virt_to_mfn(v) (pfn_to_mfn(PFN_DOWN(__pa(v)))) +#define virt_to_pfn(v) (PFN_DOWN(__pa(v))) +#define virt_to_mfn(v) (pfn_to_mfn(virt_to_pfn(v))) #define mfn_to_virt(m) (__va(mfn_to_pfn(m) << PAGE_SHIFT)) static inline unsigned long pte_mfn(pte_t pte) -- cgit v1.2.3 From 5f241e65f2be4661a33e1937e1c829252a80b2b8 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Mon, 16 Mar 2009 17:08:48 -0700 Subject: x86-64: non-paravirt systems always has PSE and PGE A paravirtualized system may not have PSE or PGE available to guests, so they are not required features. However, without paravirt we can assume that any x86-64 implementation will have them available. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/include/asm/required-features.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/required-features.h b/arch/x86/include/asm/required-features.h index a4737dddfd58..64cf2d24fad1 100644 --- a/arch/x86/include/asm/required-features.h +++ b/arch/x86/include/asm/required-features.h @@ -48,9 +48,15 @@ #endif #ifdef CONFIG_X86_64 +#ifdef CONFIG_PARAVIRT +/* Paravirtualized systems may not have PSE or PGE available */ #define NEED_PSE 0 -#define NEED_MSR (1<<(X86_FEATURE_MSR & 31)) #define NEED_PGE 0 +#else +#define NEED_PSE (1<<(X86_FEATURE_PSE) & 31) +#define NEED_PGE (1<<(X86_FEATURE_PGE) & 31) +#endif +#define NEED_MSR (1<<(X86_FEATURE_MSR & 31)) #define NEED_FXSR (1<<(X86_FEATURE_FXSR & 31)) #define NEED_XMM (1<<(X86_FEATURE_XMM & 31)) #define NEED_XMM2 (1<<(X86_FEATURE_XMM2 & 31)) -- cgit v1.2.3 From 4185f35404dc96f8525298c7c548aee419f3b3f4 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Tue, 17 Mar 2009 13:30:55 -0700 Subject: xen/mmu: some early pagetable cleanups 1. make sure early-allocated ptes are pinned, so they can be later unpinned 2. don't pin pmd+pud, just make them RO 3. scatter some __inits around Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/mmu.c | 40 ++++++++++++++++++++++++++++------------ arch/x86/xen/xen-ops.h | 2 -- 2 files changed, 28 insertions(+), 14 deletions(-) diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 67d2ab45cd90..df87c803cecc 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -1013,7 +1013,7 @@ static __init int xen_mark_pinned(struct mm_struct *mm, struct page *page, return 0; } -void __init xen_mark_init_mm_pinned(void) +static void __init xen_mark_init_mm_pinned(void) { xen_pgd_walk(&init_mm, xen_mark_pinned, FIXADDR_TOP); } @@ -1461,10 +1461,29 @@ static __init void xen_set_pte_init(pte_t *ptep, pte_t pte) } #endif +static void pin_pagetable_pfn(unsigned cmd, unsigned long pfn) +{ + struct mmuext_op op; + op.cmd = cmd; + op.arg1.mfn = pfn_to_mfn(pfn); + if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF)) + BUG(); +} + /* Early in boot, while setting up the initial pagetable, assume everything is pinned. */ static __init void xen_alloc_pte_init(struct mm_struct *mm, unsigned long pfn) { +#ifdef CONFIG_FLATMEM + BUG_ON(mem_map); /* should only be used early */ +#endif + make_lowmem_page_readonly(__va(PFN_PHYS(pfn))); + pin_pagetable_pfn(MMUEXT_PIN_L1_TABLE, pfn); +} + +/* Used for pmd and pud */ +static __init void xen_alloc_pmd_init(struct mm_struct *mm, unsigned long pfn) +{ #ifdef CONFIG_FLATMEM BUG_ON(mem_map); /* should only be used early */ #endif @@ -1473,18 +1492,15 @@ static __init void xen_alloc_pte_init(struct mm_struct *mm, unsigned long pfn) /* Early release_pte assumes that all pts are pinned, since there's only init_mm and anything attached to that is pinned. */ -static void xen_release_pte_init(unsigned long pfn) +static __init void xen_release_pte_init(unsigned long pfn) { + pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, pfn); make_lowmem_page_readwrite(__va(PFN_PHYS(pfn))); } -static void pin_pagetable_pfn(unsigned cmd, unsigned long pfn) +static __init void xen_release_pmd_init(unsigned long pfn) { - struct mmuext_op op; - op.cmd = cmd; - op.arg1.mfn = pfn_to_mfn(pfn); - if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF)) - BUG(); + make_lowmem_page_readwrite(__va(PFN_PHYS(pfn))); } /* This needs to make sure the new pte page is pinned iff its being @@ -1873,9 +1889,9 @@ const struct pv_mmu_ops xen_mmu_ops __initdata = { .alloc_pte = xen_alloc_pte_init, .release_pte = xen_release_pte_init, - .alloc_pmd = xen_alloc_pte_init, + .alloc_pmd = xen_alloc_pmd_init, .alloc_pmd_clone = paravirt_nop, - .release_pmd = xen_release_pte_init, + .release_pmd = xen_release_pmd_init, #ifdef CONFIG_HIGHPTE .kmap_atomic_pte = xen_kmap_atomic_pte, @@ -1914,8 +1930,8 @@ const struct pv_mmu_ops xen_mmu_ops __initdata = { .make_pud = PV_CALLEE_SAVE(xen_make_pud), .set_pgd = xen_set_pgd_hyper, - .alloc_pud = xen_alloc_pte_init, - .release_pud = xen_release_pte_init, + .alloc_pud = xen_alloc_pmd_init, + .release_pud = xen_release_pmd_init, #endif /* PAGETABLE_LEVELS == 4 */ .activate_mm = xen_activate_mm, diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h index f897cdffccb6..5c50a1017a37 100644 --- a/arch/x86/xen/xen-ops.h +++ b/arch/x86/xen/xen-ops.h @@ -56,8 +56,6 @@ irqreturn_t xen_debug_interrupt(int irq, void *dev_id); bool xen_vcpu_stolen(int vcpu); -void xen_mark_init_mm_pinned(void); - void xen_setup_vcpu_info_placement(void); #ifdef CONFIG_SMP -- cgit v1.2.3 From 8de07bbdede03598801cf33ab23dcbcd28a918d2 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Wed, 4 Mar 2009 17:36:57 -0800 Subject: xen/mmu: weaken flush_tlb_other test Impact: fixes crashing bug There's no particular problem with getting an empty cpu mask, so just shortcut-return if we get one. Avoids crash reported by Christophe Saout Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/mmu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index df87c803cecc..e425a32e0a90 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -1293,8 +1293,8 @@ static void xen_flush_tlb_others(const struct cpumask *cpus, } *args; struct multicall_space mcs; - BUG_ON(cpumask_empty(cpus)); - BUG_ON(!mm); + if (cpumask_empty(cpus)) + return; /* nothing to do */ mcs = xen_mc_entry(sizeof(*args)); args = mcs.args; -- cgit v1.2.3 From 1e6fcf840e11ceff8a656a678c6e4b0560a98e08 Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Wed, 25 Mar 2009 17:46:42 +0000 Subject: xen: resume interrupts before system devices. Impact: bugfix Xen domain restore Otherwise the first timer interrupt after resume is missed and we never get another. Signed-off-by: Ian Campbell Signed-off-by: Jeremy Fitzhardinge --- drivers/xen/manage.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c index 3ccd348d112d..b703dd2c9f11 100644 --- a/drivers/xen/manage.c +++ b/drivers/xen/manage.c @@ -68,15 +68,15 @@ static int xen_suspend(void *data) gnttab_resume(); xen_mm_unpin_all(); - sysdev_resume(); - device_power_up(PMSG_RESUME); - if (!*cancelled) { xen_irq_resume(); xen_console_resume(); xen_timer_resume(); } + sysdev_resume(); + device_power_up(PMSG_RESUME); + return 0; } -- cgit v1.2.3 From 707ebbc81c61eb480d8a51ca61e355e240df1d32 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Fri, 27 Mar 2009 11:29:02 -0700 Subject: xen: set _PAGE_NX in __supported_pte_mask before pagetable construction Some 64-bit machines don't support the NX flag in ptes. Check for NX before constructing the kernel pagetables. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/enlighten.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index da33e0c5870d..80f4c5343495 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -42,6 +42,7 @@ #include #include #include +#include #include #include #include @@ -912,7 +913,6 @@ static const struct machine_ops __initdata xen_machine_ops = { .emergency_restart = xen_emergency_restart, }; - /* First C function to be called on Xen boot */ asmlinkage void __init xen_start_kernel(void) { @@ -980,6 +980,11 @@ asmlinkage void __init xen_start_kernel(void) if (!xen_initial_domain()) __supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD); +#ifdef CONFIG_X86_64 + /* Work out if we support NX */ + check_efer(); +#endif + /* Don't do the full vcpu_info placement stuff until we have a possible map and a non-dummy shared_info. */ per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0]; -- cgit v1.2.3 From 6d02c42698f99eccb290ac53d4f10ca883b9f90c Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Sun, 29 Mar 2009 22:57:15 -0700 Subject: xen: clean up gate trap/interrupt constants Use GATE_INTERRUPT/TRAP rather than 0xe/f. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/enlighten.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 80f4c5343495..12a3159333bc 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -428,7 +428,7 @@ static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum, static int cvt_gate_to_trap(int vector, const gate_desc *val, struct trap_info *info) { - if (val->type != 0xf && val->type != 0xe) + if (val->type != GATE_TRAP && val->type != GATE_INTERRUPT) return 0; info->vector = vector; @@ -436,8 +436,8 @@ static int cvt_gate_to_trap(int vector, const gate_desc *val, info->cs = gate_segment(*val); info->flags = val->dpl; /* interrupt gates clear IF */ - if (val->type == 0xe) - info->flags |= 4; + if (val->type == GATE_INTERRUPT) + info->flags |= 1 << 2; return 1; } -- cgit v1.2.3 From d4c045364d3107603187f21a56ec231e74d26441 Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Fri, 6 Feb 2009 19:20:31 -0800 Subject: xen: add irq_from_evtchn Given an evtchn, return the corresponding irq. Signed-off-by: Ian Campbell Signed-off-by: Jeremy Fitzhardinge --- drivers/xen/events.c | 6 ++++++ include/xen/events.h | 3 +++ 2 files changed, 9 insertions(+) diff --git a/drivers/xen/events.c b/drivers/xen/events.c index 30963af5dba0..1cd2a0e15ae8 100644 --- a/drivers/xen/events.c +++ b/drivers/xen/events.c @@ -151,6 +151,12 @@ static unsigned int evtchn_from_irq(unsigned irq) return info_for_irq(irq)->evtchn; } +unsigned irq_from_evtchn(unsigned int evtchn) +{ + return evtchn_to_irq[evtchn]; +} +EXPORT_SYMBOL_GPL(irq_from_evtchn); + static enum ipi_vector ipi_from_irq(unsigned irq) { struct irq_info *info = info_for_irq(irq); diff --git a/include/xen/events.h b/include/xen/events.h index 0d5f1adc0363..e68d59a90ca8 100644 --- a/include/xen/events.h +++ b/include/xen/events.h @@ -53,4 +53,7 @@ bool xen_test_irq_pending(int irq); irq will be disabled so it won't deliver an interrupt. */ void xen_poll_irq(int irq); +/* Determine the IRQ which is bound to an event channel */ +unsigned irq_from_evtchn(unsigned int evtchn); + #endif /* _XEN_EVENTS_H */ -- cgit v1.2.3 From f7116284c734f3a47180cd9c907944a1837ccb3c Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Fri, 6 Feb 2009 19:21:19 -0800 Subject: xen: add /dev/xen/evtchn driver This driver is used by application which wish to receive notifications from the hypervisor or other guests via Xen's event channel mechanism. In particular it is used by the xenstore daemon in domain 0. Signed-off-by: Ian Campbell Signed-off-by: Jeremy Fitzhardinge --- drivers/xen/Kconfig | 10 ++ drivers/xen/Makefile | 3 +- drivers/xen/evtchn.c | 494 +++++++++++++++++++++++++++++++++++++++++++++++++++ include/xen/evtchn.h | 88 +++++++++ 4 files changed, 594 insertions(+), 1 deletion(-) create mode 100644 drivers/xen/evtchn.c create mode 100644 include/xen/evtchn.h diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig index 526187c8a12d..1bbb9108f31e 100644 --- a/drivers/xen/Kconfig +++ b/drivers/xen/Kconfig @@ -18,6 +18,16 @@ config XEN_SCRUB_PAGES secure, but slightly less efficient. If in doubt, say yes. +config XEN_DEV_EVTCHN + tristate "Xen /dev/xen/evtchn device" + depends on XEN + default y + help + The evtchn driver allows a userspace process to triger event + channels and to receive notification of an event channel + firing. + If in doubt, say yes. + config XENFS tristate "Xen filesystem" depends on XEN diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile index ff8accc9e103..1567639847e7 100644 --- a/drivers/xen/Makefile +++ b/drivers/xen/Makefile @@ -4,4 +4,5 @@ obj-y += xenbus/ obj-$(CONFIG_HOTPLUG_CPU) += cpu_hotplug.o obj-$(CONFIG_XEN_XENCOMM) += xencomm.o obj-$(CONFIG_XEN_BALLOON) += balloon.o -obj-$(CONFIG_XENFS) += xenfs/ \ No newline at end of file +obj-$(CONFIG_XEN_DEV_EVTCHN) += evtchn.o +obj-$(CONFIG_XENFS) += xenfs/ diff --git a/drivers/xen/evtchn.c b/drivers/xen/evtchn.c new file mode 100644 index 000000000000..517b9ee63e18 --- /dev/null +++ b/drivers/xen/evtchn.c @@ -0,0 +1,494 @@ +/****************************************************************************** + * evtchn.c + * + * Driver for receiving and demuxing event-channel signals. + * + * Copyright (c) 2004-2005, K A Fraser + * Multi-process extensions Copyright (c) 2004, Steven Smith + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation; or, when distributed + * separately from the Linux kernel or incorporated into other + * software packages, subject to the following license: + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this source file (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, modify, + * merge, publish, distribute, sublicense, and/or sell copies of the Software, + * and to permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct per_user_data { + /* Notification ring, accessed via /dev/xen/evtchn. */ +#define EVTCHN_RING_SIZE (PAGE_SIZE / sizeof(evtchn_port_t)) +#define EVTCHN_RING_MASK(_i) ((_i)&(EVTCHN_RING_SIZE-1)) + evtchn_port_t *ring; + unsigned int ring_cons, ring_prod, ring_overflow; + struct mutex ring_cons_mutex; /* protect against concurrent readers */ + + /* Processes wait on this queue when ring is empty. */ + wait_queue_head_t evtchn_wait; + struct fasync_struct *evtchn_async_queue; + const char *name; +}; + +/* Who's bound to each port? */ +static struct per_user_data *port_user[NR_EVENT_CHANNELS]; +static DEFINE_SPINLOCK(port_user_lock); + +irqreturn_t evtchn_interrupt(int irq, void *data) +{ + unsigned int port = (unsigned long)data; + struct per_user_data *u; + + spin_lock(&port_user_lock); + + u = port_user[port]; + + disable_irq_nosync(irq); + + if ((u->ring_prod - u->ring_cons) < EVTCHN_RING_SIZE) { + u->ring[EVTCHN_RING_MASK(u->ring_prod)] = port; + wmb(); /* Ensure ring contents visible */ + if (u->ring_cons == u->ring_prod++) { + wake_up_interruptible(&u->evtchn_wait); + kill_fasync(&u->evtchn_async_queue, + SIGIO, POLL_IN); + } + } else { + u->ring_overflow = 1; + } + + spin_unlock(&port_user_lock); + + return IRQ_HANDLED; +} + +static ssize_t evtchn_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + int rc; + unsigned int c, p, bytes1 = 0, bytes2 = 0; + struct per_user_data *u = file->private_data; + + /* Whole number of ports. */ + count &= ~(sizeof(evtchn_port_t)-1); + + if (count == 0) + return 0; + + if (count > PAGE_SIZE) + count = PAGE_SIZE; + + for (;;) { + mutex_lock(&u->ring_cons_mutex); + + rc = -EFBIG; + if (u->ring_overflow) + goto unlock_out; + + c = u->ring_cons; + p = u->ring_prod; + if (c != p) + break; + + mutex_unlock(&u->ring_cons_mutex); + + if (file->f_flags & O_NONBLOCK) + return -EAGAIN; + + rc = wait_event_interruptible(u->evtchn_wait, + u->ring_cons != u->ring_prod); + if (rc) + return rc; + } + + /* Byte lengths of two chunks. Chunk split (if any) is at ring wrap. */ + if (((c ^ p) & EVTCHN_RING_SIZE) != 0) { + bytes1 = (EVTCHN_RING_SIZE - EVTCHN_RING_MASK(c)) * + sizeof(evtchn_port_t); + bytes2 = EVTCHN_RING_MASK(p) * sizeof(evtchn_port_t); + } else { + bytes1 = (p - c) * sizeof(evtchn_port_t); + bytes2 = 0; + } + + /* Truncate chunks according to caller's maximum byte count. */ + if (bytes1 > count) { + bytes1 = count; + bytes2 = 0; + } else if ((bytes1 + bytes2) > count) { + bytes2 = count - bytes1; + } + + rc = -EFAULT; + rmb(); /* Ensure that we see the port before we copy it. */ + if (copy_to_user(buf, &u->ring[EVTCHN_RING_MASK(c)], bytes1) || + ((bytes2 != 0) && + copy_to_user(&buf[bytes1], &u->ring[0], bytes2))) + goto unlock_out; + + u->ring_cons += (bytes1 + bytes2) / sizeof(evtchn_port_t); + rc = bytes1 + bytes2; + + unlock_out: + mutex_unlock(&u->ring_cons_mutex); + return rc; +} + +static ssize_t evtchn_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + int rc, i; + evtchn_port_t *kbuf = (evtchn_port_t *)__get_free_page(GFP_KERNEL); + struct per_user_data *u = file->private_data; + + if (kbuf == NULL) + return -ENOMEM; + + /* Whole number of ports. */ + count &= ~(sizeof(evtchn_port_t)-1); + + rc = 0; + if (count == 0) + goto out; + + if (count > PAGE_SIZE) + count = PAGE_SIZE; + + rc = -EFAULT; + if (copy_from_user(kbuf, buf, count) != 0) + goto out; + + spin_lock_irq(&port_user_lock); + for (i = 0; i < (count/sizeof(evtchn_port_t)); i++) + if ((kbuf[i] < NR_EVENT_CHANNELS) && (port_user[kbuf[i]] == u)) + enable_irq(irq_from_evtchn(kbuf[i])); + spin_unlock_irq(&port_user_lock); + + rc = count; + + out: + free_page((unsigned long)kbuf); + return rc; +} + +static int evtchn_bind_to_user(struct per_user_data *u, int port) +{ + int irq; + int rc = 0; + + spin_lock_irq(&port_user_lock); + + BUG_ON(port_user[port] != NULL); + + irq = bind_evtchn_to_irqhandler(port, evtchn_interrupt, IRQF_DISABLED, + u->name, (void *)(unsigned long)port); + if (rc < 0) + goto fail; + + port_user[port] = u; + +fail: + spin_unlock_irq(&port_user_lock); + return rc; +} + +static void evtchn_unbind_from_user(struct per_user_data *u, int port) +{ + int irq = irq_from_evtchn(port); + + unbind_from_irqhandler(irq, (void *)(unsigned long)port); + port_user[port] = NULL; +} + +static long evtchn_ioctl(struct file *file, + unsigned int cmd, unsigned long arg) +{ + int rc; + struct per_user_data *u = file->private_data; + void __user *uarg = (void __user *) arg; + + switch (cmd) { + case IOCTL_EVTCHN_BIND_VIRQ: { + struct ioctl_evtchn_bind_virq bind; + struct evtchn_bind_virq bind_virq; + + rc = -EFAULT; + if (copy_from_user(&bind, uarg, sizeof(bind))) + break; + + bind_virq.virq = bind.virq; + bind_virq.vcpu = 0; + rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_virq, + &bind_virq); + if (rc != 0) + break; + + rc = evtchn_bind_to_user(u, bind_virq.port); + if (rc == 0) + rc = bind_virq.port; + break; + } + + case IOCTL_EVTCHN_BIND_INTERDOMAIN: { + struct ioctl_evtchn_bind_interdomain bind; + struct evtchn_bind_interdomain bind_interdomain; + + rc = -EFAULT; + if (copy_from_user(&bind, uarg, sizeof(bind))) + break; + + bind_interdomain.remote_dom = bind.remote_domain; + bind_interdomain.remote_port = bind.remote_port; + rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_interdomain, + &bind_interdomain); + if (rc != 0) + break; + + rc = evtchn_bind_to_user(u, bind_interdomain.local_port); + if (rc == 0) + rc = bind_interdomain.local_port; + break; + } + + case IOCTL_EVTCHN_BIND_UNBOUND_PORT: { + struct ioctl_evtchn_bind_unbound_port bind; + struct evtchn_alloc_unbound alloc_unbound; + + rc = -EFAULT; + if (copy_from_user(&bind, uarg, sizeof(bind))) + break; + + alloc_unbound.dom = DOMID_SELF; + alloc_unbound.remote_dom = bind.remote_domain; + rc = HYPERVISOR_event_channel_op(EVTCHNOP_alloc_unbound, + &alloc_unbound); + if (rc != 0) + break; + + rc = evtchn_bind_to_user(u, alloc_unbound.port); + if (rc == 0) + rc = alloc_unbound.port; + break; + } + + case IOCTL_EVTCHN_UNBIND: { + struct ioctl_evtchn_unbind unbind; + + rc = -EFAULT; + if (copy_from_user(&unbind, uarg, sizeof(unbind))) + break; + + rc = -EINVAL; + if (unbind.port >= NR_EVENT_CHANNELS) + break; + + spin_lock_irq(&port_user_lock); + + rc = -ENOTCONN; + if (port_user[unbind.port] != u) { + spin_unlock_irq(&port_user_lock); + break; + } + + evtchn_unbind_from_user(u, unbind.port); + + spin_unlock_irq(&port_user_lock); + + rc = 0; + break; + } + + case IOCTL_EVTCHN_NOTIFY: { + struct ioctl_evtchn_notify notify; + + rc = -EFAULT; + if (copy_from_user(¬ify, uarg, sizeof(notify))) + break; + + if (notify.port >= NR_EVENT_CHANNELS) { + rc = -EINVAL; + } else if (port_user[notify.port] != u) { + rc = -ENOTCONN; + } else { + notify_remote_via_evtchn(notify.port); + rc = 0; + } + break; + } + + case IOCTL_EVTCHN_RESET: { + /* Initialise the ring to empty. Clear errors. */ + mutex_lock(&u->ring_cons_mutex); + spin_lock_irq(&port_user_lock); + u->ring_cons = u->ring_prod = u->ring_overflow = 0; + spin_unlock_irq(&port_user_lock); + mutex_unlock(&u->ring_cons_mutex); + rc = 0; + break; + } + + default: + rc = -ENOSYS; + break; + } + + return rc; +} + +static unsigned int evtchn_poll(struct file *file, poll_table *wait) +{ + unsigned int mask = POLLOUT | POLLWRNORM; + struct per_user_data *u = file->private_data; + + poll_wait(file, &u->evtchn_wait, wait); + if (u->ring_cons != u->ring_prod) + mask |= POLLIN | POLLRDNORM; + if (u->ring_overflow) + mask = POLLERR; + return mask; +} + +static int evtchn_fasync(int fd, struct file *filp, int on) +{ + struct per_user_data *u = filp->private_data; + return fasync_helper(fd, filp, on, &u->evtchn_async_queue); +} + +static int evtchn_open(struct inode *inode, struct file *filp) +{ + struct per_user_data *u; + + u = kzalloc(sizeof(*u), GFP_KERNEL); + if (u == NULL) + return -ENOMEM; + + u->name = kasprintf(GFP_KERNEL, "evtchn:%s", current->comm); + if (u->name == NULL) { + kfree(u); + return -ENOMEM; + } + + init_waitqueue_head(&u->evtchn_wait); + + u->ring = (evtchn_port_t *)__get_free_page(GFP_KERNEL); + if (u->ring == NULL) { + kfree(u->name); + kfree(u); + return -ENOMEM; + } + + mutex_init(&u->ring_cons_mutex); + + filp->private_data = u; + + return 0; +} + +static int evtchn_release(struct inode *inode, struct file *filp) +{ + int i; + struct per_user_data *u = filp->private_data; + + spin_lock_irq(&port_user_lock); + + free_page((unsigned long)u->ring); + + for (i = 0; i < NR_EVENT_CHANNELS; i++) { + if (port_user[i] != u) + continue; + + evtchn_unbind_from_user(port_user[i], i); + } + + spin_unlock_irq(&port_user_lock); + + kfree(u->name); + kfree(u); + + return 0; +} + +static const struct file_operations evtchn_fops = { + .owner = THIS_MODULE, + .read = evtchn_read, + .write = evtchn_write, + .unlocked_ioctl = evtchn_ioctl, + .poll = evtchn_poll, + .fasync = evtchn_fasync, + .open = evtchn_open, + .release = evtchn_release, +}; + +static struct miscdevice evtchn_miscdev = { + .minor = MISC_DYNAMIC_MINOR, + .name = "evtchn", + .fops = &evtchn_fops, +}; +static int __init evtchn_init(void) +{ + int err; + + if (!xen_domain()) + return -ENODEV; + + spin_lock_init(&port_user_lock); + memset(port_user, 0, sizeof(port_user)); + + /* Create '/dev/misc/evtchn'. */ + err = misc_register(&evtchn_miscdev); + if (err != 0) { + printk(KERN_ALERT "Could not register /dev/misc/evtchn\n"); + return err; + } + + printk(KERN_INFO "Event-channel device installed.\n"); + + return 0; +} + +static void __exit evtchn_cleanup(void) +{ + misc_deregister(&evtchn_miscdev); +} + +module_init(evtchn_init); +module_exit(evtchn_cleanup); + +MODULE_LICENSE("GPL"); diff --git a/include/xen/evtchn.h b/include/xen/evtchn.h new file mode 100644 index 000000000000..14e833ee4e0b --- /dev/null +++ b/include/xen/evtchn.h @@ -0,0 +1,88 @@ +/****************************************************************************** + * evtchn.h + * + * Interface to /dev/xen/evtchn. + * + * Copyright (c) 2003-2005, K A Fraser + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation; or, when distributed + * separately from the Linux kernel or incorporated into other + * software packages, subject to the following license: + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this source file (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, copy, modify, + * merge, publish, distribute, sublicense, and/or sell copies of the Software, + * and to permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + */ + +#ifndef __LINUX_PUBLIC_EVTCHN_H__ +#define __LINUX_PUBLIC_EVTCHN_H__ + +/* + * Bind a fresh port to VIRQ @virq. + * Return allocated port. + */ +#define IOCTL_EVTCHN_BIND_VIRQ \ + _IOC(_IOC_NONE, 'E', 0, sizeof(struct ioctl_evtchn_bind_virq)) +struct ioctl_evtchn_bind_virq { + unsigned int virq; +}; + +/* + * Bind a fresh port to remote <@remote_domain, @remote_port>. + * Return allocated port. + */ +#define IOCTL_EVTCHN_BIND_INTERDOMAIN \ + _IOC(_IOC_NONE, 'E', 1, sizeof(struct ioctl_evtchn_bind_interdomain)) +struct ioctl_evtchn_bind_interdomain { + unsigned int remote_domain, remote_port; +}; + +/* + * Allocate a fresh port for binding to @remote_domain. + * Return allocated port. + */ +#define IOCTL_EVTCHN_BIND_UNBOUND_PORT \ + _IOC(_IOC_NONE, 'E', 2, sizeof(struct ioctl_evtchn_bind_unbound_port)) +struct ioctl_evtchn_bind_unbound_port { + unsigned int remote_domain; +}; + +/* + * Unbind previously allocated @port. + */ +#define IOCTL_EVTCHN_UNBIND \ + _IOC(_IOC_NONE, 'E', 3, sizeof(struct ioctl_evtchn_unbind)) +struct ioctl_evtchn_unbind { + unsigned int port; +}; + +/* + * Unbind previously allocated @port. + */ +#define IOCTL_EVTCHN_NOTIFY \ + _IOC(_IOC_NONE, 'E', 4, sizeof(struct ioctl_evtchn_notify)) +struct ioctl_evtchn_notify { + unsigned int port; +}; + +/* Clear and reinitialise the event buffer. Clear error condition. */ +#define IOCTL_EVTCHN_RESET \ + _IOC(_IOC_NONE, 'E', 5, 0) + +#endif /* __LINUX_PUBLIC_EVTCHN_H__ */ -- cgit v1.2.3 From c5cfef0f79cacc3aa438fc28f4747f0d10c54d0d Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Fri, 6 Feb 2009 19:21:19 -0800 Subject: xen: export ioctl headers to userspace Signed-off-by: Ian Campbell Signed-off-by: Jeremy Fitzhardinge --- include/Kbuild | 1 + include/xen/Kbuild | 1 + 2 files changed, 2 insertions(+) create mode 100644 include/xen/Kbuild diff --git a/include/Kbuild b/include/Kbuild index d8c3e3cbf416..fe36accd4328 100644 --- a/include/Kbuild +++ b/include/Kbuild @@ -8,3 +8,4 @@ header-y += mtd/ header-y += rdma/ header-y += video/ header-y += drm/ +header-y += xen/ diff --git a/include/xen/Kbuild b/include/xen/Kbuild new file mode 100644 index 000000000000..4e65c16a445b --- /dev/null +++ b/include/xen/Kbuild @@ -0,0 +1 @@ +header-y += evtchn.h -- cgit v1.2.3 From 0a4666b539a0e896ec4e8396a034a479e3573125 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Thu, 12 Feb 2009 13:03:24 -0800 Subject: xen/dev-evtchn: clean up locking in evtchn Define a new per_user_data mutex to serialize bind/unbind operations to prevent them from racing with each other. Fix error returns and don't do a bind while holding a spinlock. Signed-off-by: Jeremy Fitzhardinge --- drivers/xen/evtchn.c | 37 +++++++++++++++++++++++++------------ 1 file changed, 25 insertions(+), 12 deletions(-) diff --git a/drivers/xen/evtchn.c b/drivers/xen/evtchn.c index 517b9ee63e18..af031950f9b1 100644 --- a/drivers/xen/evtchn.c +++ b/drivers/xen/evtchn.c @@ -54,6 +54,8 @@ #include struct per_user_data { + struct mutex bind_mutex; /* serialize bind/unbind operations */ + /* Notification ring, accessed via /dev/xen/evtchn. */ #define EVTCHN_RING_SIZE (PAGE_SIZE / sizeof(evtchn_port_t)) #define EVTCHN_RING_MASK(_i) ((_i)&(EVTCHN_RING_SIZE-1)) @@ -69,7 +71,7 @@ struct per_user_data { /* Who's bound to each port? */ static struct per_user_data *port_user[NR_EVENT_CHANNELS]; -static DEFINE_SPINLOCK(port_user_lock); +static DEFINE_SPINLOCK(port_user_lock); /* protects port_user[] and ring_prod */ irqreturn_t evtchn_interrupt(int irq, void *data) { @@ -210,22 +212,24 @@ static ssize_t evtchn_write(struct file *file, const char __user *buf, static int evtchn_bind_to_user(struct per_user_data *u, int port) { - int irq; int rc = 0; - spin_lock_irq(&port_user_lock); - + /* + * Ports are never reused, so every caller should pass in a + * unique port. + * + * (Locking not necessary because we haven't registered the + * interrupt handler yet, and our caller has already + * serialized bind operations.) + */ BUG_ON(port_user[port] != NULL); - - irq = bind_evtchn_to_irqhandler(port, evtchn_interrupt, IRQF_DISABLED, - u->name, (void *)(unsigned long)port); - if (rc < 0) - goto fail; - port_user[port] = u; -fail: - spin_unlock_irq(&port_user_lock); + rc = bind_evtchn_to_irqhandler(port, evtchn_interrupt, IRQF_DISABLED, + u->name, (void *)(unsigned long)port); + if (rc >= 0) + rc = 0; + return rc; } @@ -234,6 +238,10 @@ static void evtchn_unbind_from_user(struct per_user_data *u, int port) int irq = irq_from_evtchn(port); unbind_from_irqhandler(irq, (void *)(unsigned long)port); + + /* make sure we unbind the irq handler before clearing the port */ + barrier(); + port_user[port] = NULL; } @@ -244,6 +252,9 @@ static long evtchn_ioctl(struct file *file, struct per_user_data *u = file->private_data; void __user *uarg = (void __user *) arg; + /* Prevent bind from racing with unbind */ + mutex_lock(&u->bind_mutex); + switch (cmd) { case IOCTL_EVTCHN_BIND_VIRQ: { struct ioctl_evtchn_bind_virq bind; @@ -368,6 +379,7 @@ static long evtchn_ioctl(struct file *file, rc = -ENOSYS; break; } + mutex_unlock(&u->bind_mutex); return rc; } @@ -414,6 +426,7 @@ static int evtchn_open(struct inode *inode, struct file *filp) return -ENOMEM; } + mutex_init(&u->bind_mutex); mutex_init(&u->ring_cons_mutex); filp->private_data = u; -- cgit v1.2.3 From a1ce1be578365a4da7e7d7db4812539d2d5da763 Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Mon, 9 Feb 2009 12:05:50 -0800 Subject: xen: remove suspend_cancel hook Remove suspend_cancel hook from xenbus_driver, in preparation for using the device model for suspending. Signed-off-by: Ian Campbell Signed-off-by: Jeremy Fitzhardinge --- drivers/xen/xenbus/xenbus_probe.c | 23 ----------------------- include/xen/xenbus.h | 1 - 2 files changed, 24 deletions(-) diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c index 773d1cf23283..bd20361fb099 100644 --- a/drivers/xen/xenbus/xenbus_probe.c +++ b/drivers/xen/xenbus/xenbus_probe.c @@ -689,27 +689,6 @@ static int suspend_dev(struct device *dev, void *data) return 0; } -static int suspend_cancel_dev(struct device *dev, void *data) -{ - int err = 0; - struct xenbus_driver *drv; - struct xenbus_device *xdev; - - DPRINTK(""); - - if (dev->driver == NULL) - return 0; - drv = to_xenbus_driver(dev->driver); - xdev = container_of(dev, struct xenbus_device, dev); - if (drv->suspend_cancel) - err = drv->suspend_cancel(xdev); - if (err) - printk(KERN_WARNING - "xenbus: suspend_cancel %s failed: %i\n", - dev_name(dev), err); - return 0; -} - static int resume_dev(struct device *dev, void *data) { int err; @@ -777,8 +756,6 @@ EXPORT_SYMBOL_GPL(xenbus_resume); void xenbus_suspend_cancel(void) { xs_suspend_cancel(); - bus_for_each_dev(&xenbus_frontend.bus, NULL, NULL, suspend_cancel_dev); - xenbus_backend_resume(suspend_cancel_dev); } EXPORT_SYMBOL_GPL(xenbus_suspend_cancel); diff --git a/include/xen/xenbus.h b/include/xen/xenbus.h index f87f9614844d..0836772b9686 100644 --- a/include/xen/xenbus.h +++ b/include/xen/xenbus.h @@ -92,7 +92,6 @@ struct xenbus_driver { enum xenbus_state backend_state); int (*remove)(struct xenbus_device *dev); int (*suspend)(struct xenbus_device *dev); - int (*suspend_cancel)(struct xenbus_device *dev); int (*resume)(struct xenbus_device *dev); int (*uevent)(struct xenbus_device *, char **, int, char *, int); struct device_driver driver; -- cgit v1.2.3 From de5b31bd47de7e6f41be2e271318dbc8f1af354d Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Mon, 9 Feb 2009 12:05:50 -0800 Subject: xen: use device model for suspending xenbus devices Signed-off-by: Ian Campbell Signed-off-by: Jeremy Fitzhardinge --- drivers/xen/manage.c | 9 ++++----- drivers/xen/xenbus/xenbus_probe.c | 37 +++++++++---------------------------- drivers/xen/xenbus/xenbus_xs.c | 2 ++ include/xen/xenbus.h | 2 +- 4 files changed, 16 insertions(+), 34 deletions(-) diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c index b703dd2c9f11..5269bb4d2496 100644 --- a/drivers/xen/manage.c +++ b/drivers/xen/manage.c @@ -104,9 +104,8 @@ static void do_suspend(void) goto out; } - printk("suspending xenbus...\n"); - /* XXX use normal device tree? */ - xenbus_suspend(); + printk(KERN_DEBUG "suspending xenstore...\n"); + xs_suspend(); err = stop_machine(xen_suspend, &cancelled, cpumask_of(0)); if (err) { @@ -116,9 +115,9 @@ static void do_suspend(void) if (!cancelled) { xen_arch_resume(); - xenbus_resume(); + xs_resume(); } else - xenbus_suspend_cancel(); + xs_suspend_cancel(); device_resume(PMSG_RESUME); diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c index bd20361fb099..4649213bed9e 100644 --- a/drivers/xen/xenbus/xenbus_probe.c +++ b/drivers/xen/xenbus/xenbus_probe.c @@ -71,6 +71,9 @@ static int xenbus_probe_frontend(const char *type, const char *name); static void xenbus_dev_shutdown(struct device *_dev); +static int xenbus_dev_suspend(struct device *dev, pm_message_t state); +static int xenbus_dev_resume(struct device *dev); + /* If something in array of ids matches this device, return it. */ static const struct xenbus_device_id * match_device(const struct xenbus_device_id *arr, struct xenbus_device *dev) @@ -188,6 +191,9 @@ static struct xen_bus_type xenbus_frontend = { .remove = xenbus_dev_remove, .shutdown = xenbus_dev_shutdown, .dev_attrs = xenbus_dev_attrs, + + .suspend = xenbus_dev_suspend, + .resume = xenbus_dev_resume, }, }; @@ -669,7 +675,7 @@ static struct xenbus_watch fe_watch = { .callback = frontend_changed, }; -static int suspend_dev(struct device *dev, void *data) +static int xenbus_dev_suspend(struct device *dev, pm_message_t state) { int err = 0; struct xenbus_driver *drv; @@ -682,14 +688,14 @@ static int suspend_dev(struct device *dev, void *data) drv = to_xenbus_driver(dev->driver); xdev = container_of(dev, struct xenbus_device, dev); if (drv->suspend) - err = drv->suspend(xdev); + err = drv->suspend(xdev, state); if (err) printk(KERN_WARNING "xenbus: suspend %s failed: %i\n", dev_name(dev), err); return 0; } -static int resume_dev(struct device *dev, void *data) +static int xenbus_dev_resume(struct device *dev) { int err; struct xenbus_driver *drv; @@ -734,31 +740,6 @@ static int resume_dev(struct device *dev, void *data) return 0; } -void xenbus_suspend(void) -{ - DPRINTK(""); - - bus_for_each_dev(&xenbus_frontend.bus, NULL, NULL, suspend_dev); - xenbus_backend_suspend(suspend_dev); - xs_suspend(); -} -EXPORT_SYMBOL_GPL(xenbus_suspend); - -void xenbus_resume(void) -{ - xb_init_comms(); - xs_resume(); - bus_for_each_dev(&xenbus_frontend.bus, NULL, NULL, resume_dev); - xenbus_backend_resume(resume_dev); -} -EXPORT_SYMBOL_GPL(xenbus_resume); - -void xenbus_suspend_cancel(void) -{ - xs_suspend_cancel(); -} -EXPORT_SYMBOL_GPL(xenbus_suspend_cancel); - /* A flag to determine if xenstored is 'ready' (i.e. has started) */ int xenstored_ready = 0; diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c index e325eab4724d..eab33f1dbdf7 100644 --- a/drivers/xen/xenbus/xenbus_xs.c +++ b/drivers/xen/xenbus/xenbus_xs.c @@ -673,6 +673,8 @@ void xs_resume(void) struct xenbus_watch *watch; char token[sizeof(watch) * 2 + 1]; + xb_init_comms(); + mutex_unlock(&xs_state.response_mutex); mutex_unlock(&xs_state.request_mutex); up_write(&xs_state.transaction_mutex); diff --git a/include/xen/xenbus.h b/include/xen/xenbus.h index 0836772b9686..b9763badbd77 100644 --- a/include/xen/xenbus.h +++ b/include/xen/xenbus.h @@ -91,7 +91,7 @@ struct xenbus_driver { void (*otherend_changed)(struct xenbus_device *dev, enum xenbus_state backend_state); int (*remove)(struct xenbus_device *dev); - int (*suspend)(struct xenbus_device *dev); + int (*suspend)(struct xenbus_device *dev, pm_message_t state); int (*resume)(struct xenbus_device *dev); int (*uevent)(struct xenbus_device *, char **, int, char *, int); struct device_driver driver; -- cgit v1.2.3 From c6a960ce8858f20036cc3afc3b9422670d0d9021 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Mon, 9 Feb 2009 12:05:53 -0800 Subject: xen/xenbus: export xenbus_dev_changed Signed-off-by: Jeremy Fitzhardinge --- drivers/xen/xenbus/xenbus_probe.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c index 4649213bed9e..d42e25d5968d 100644 --- a/drivers/xen/xenbus/xenbus_probe.c +++ b/drivers/xen/xenbus/xenbus_probe.c @@ -660,6 +660,7 @@ void xenbus_dev_changed(const char *node, struct xen_bus_type *bus) kfree(root); } +EXPORT_SYMBOL_GPL(xenbus_dev_changed); static void frontend_changed(struct xenbus_watch *watch, const char **vec, unsigned int len) -- cgit v1.2.3 From cff7e81b3dd7c25cd2248cd7a04c5764552d5d55 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Tue, 10 Mar 2009 14:39:59 -0700 Subject: xen: add /sys/hypervisor support Adds support for Xen info under /sys/hypervisor. Taken from Novell 2.6.27 backport tree. Signed-off-by: Jeremy Fitzhardinge --- drivers/xen/Kconfig | 10 + drivers/xen/Makefile | 3 +- drivers/xen/sys-hypervisor.c | 475 ++++++++++++++++++++++++++++++++++++++++ include/xen/interface/version.h | 3 + 4 files changed, 490 insertions(+), 1 deletion(-) create mode 100644 drivers/xen/sys-hypervisor.c diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig index 526187c8a12d..88bca1c42db4 100644 --- a/drivers/xen/Kconfig +++ b/drivers/xen/Kconfig @@ -41,3 +41,13 @@ config XEN_COMPAT_XENFS a xen platform. If in doubt, say yes. +config XEN_SYS_HYPERVISOR + bool "Create xen entries under /sys/hypervisor" + depends on XEN && SYSFS + select SYS_HYPERVISOR + default y + help + Create entries under /sys/hypervisor describing the Xen + hypervisor environment. When running native or in another + virtual environment, /sys/hypervisor will still be present, + but will have no xen contents. \ No newline at end of file diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile index ff8accc9e103..f3603a39db55 100644 --- a/drivers/xen/Makefile +++ b/drivers/xen/Makefile @@ -4,4 +4,5 @@ obj-y += xenbus/ obj-$(CONFIG_HOTPLUG_CPU) += cpu_hotplug.o obj-$(CONFIG_XEN_XENCOMM) += xencomm.o obj-$(CONFIG_XEN_BALLOON) += balloon.o -obj-$(CONFIG_XENFS) += xenfs/ \ No newline at end of file +obj-$(CONFIG_XENFS) += xenfs/ +obj-$(CONFIG_XEN_SYS_HYPERVISOR) += sys-hypervisor.o diff --git a/drivers/xen/sys-hypervisor.c b/drivers/xen/sys-hypervisor.c new file mode 100644 index 000000000000..cb29d1ccf0d9 --- /dev/null +++ b/drivers/xen/sys-hypervisor.c @@ -0,0 +1,475 @@ +/* + * copyright (c) 2006 IBM Corporation + * Authored by: Mike D. Day + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include + +#include +#include + +#include +#include +#include + +#define HYPERVISOR_ATTR_RO(_name) \ +static struct hyp_sysfs_attr _name##_attr = __ATTR_RO(_name) + +#define HYPERVISOR_ATTR_RW(_name) \ +static struct hyp_sysfs_attr _name##_attr = \ + __ATTR(_name, 0644, _name##_show, _name##_store) + +struct hyp_sysfs_attr { + struct attribute attr; + ssize_t (*show)(struct hyp_sysfs_attr *, char *); + ssize_t (*store)(struct hyp_sysfs_attr *, const char *, size_t); + void *hyp_attr_data; +}; + +static ssize_t type_show(struct hyp_sysfs_attr *attr, char *buffer) +{ + return sprintf(buffer, "xen\n"); +} + +HYPERVISOR_ATTR_RO(type); + +static int __init xen_sysfs_type_init(void) +{ + return sysfs_create_file(hypervisor_kobj, &type_attr.attr); +} + +static void xen_sysfs_type_destroy(void) +{ + sysfs_remove_file(hypervisor_kobj, &type_attr.attr); +} + +/* xen version attributes */ +static ssize_t major_show(struct hyp_sysfs_attr *attr, char *buffer) +{ + int version = HYPERVISOR_xen_version(XENVER_version, NULL); + if (version) + return sprintf(buffer, "%d\n", version >> 16); + return -ENODEV; +} + +HYPERVISOR_ATTR_RO(major); + +static ssize_t minor_show(struct hyp_sysfs_attr *attr, char *buffer) +{ + int version = HYPERVISOR_xen_version(XENVER_version, NULL); + if (version) + return sprintf(buffer, "%d\n", version & 0xff); + return -ENODEV; +} + +HYPERVISOR_ATTR_RO(minor); + +static ssize_t extra_show(struct hyp_sysfs_attr *attr, char *buffer) +{ + int ret = -ENOMEM; + char *extra; + + extra = kmalloc(XEN_EXTRAVERSION_LEN, GFP_KERNEL); + if (extra) { + ret = HYPERVISOR_xen_version(XENVER_extraversion, extra); + if (!ret) + ret = sprintf(buffer, "%s\n", extra); + kfree(extra); + } + + return ret; +} + +HYPERVISOR_ATTR_RO(extra); + +static struct attribute *version_attrs[] = { + &major_attr.attr, + &minor_attr.attr, + &extra_attr.attr, + NULL +}; + +static struct attribute_group version_group = { + .name = "version", + .attrs = version_attrs, +}; + +static int __init xen_sysfs_version_init(void) +{ + return sysfs_create_group(hypervisor_kobj, &version_group); +} + +static void xen_sysfs_version_destroy(void) +{ + sysfs_remove_group(hypervisor_kobj, &version_group); +} + +/* UUID */ + +static ssize_t uuid_show(struct hyp_sysfs_attr *attr, char *buffer) +{ + char *vm, *val; + int ret; + extern int xenstored_ready; + + if (!xenstored_ready) + return -EBUSY; + + vm = xenbus_read(XBT_NIL, "vm", "", NULL); + if (IS_ERR(vm)) + return PTR_ERR(vm); + val = xenbus_read(XBT_NIL, vm, "uuid", NULL); + kfree(vm); + if (IS_ERR(val)) + return PTR_ERR(val); + ret = sprintf(buffer, "%s\n", val); + kfree(val); + return ret; +} + +HYPERVISOR_ATTR_RO(uuid); + +static int __init xen_sysfs_uuid_init(void) +{ + return sysfs_create_file(hypervisor_kobj, &uuid_attr.attr); +} + +static void xen_sysfs_uuid_destroy(void) +{ + sysfs_remove_file(hypervisor_kobj, &uuid_attr.attr); +} + +/* xen compilation attributes */ + +static ssize_t compiler_show(struct hyp_sysfs_attr *attr, char *buffer) +{ + int ret = -ENOMEM; + struct xen_compile_info *info; + + info = kmalloc(sizeof(struct xen_compile_info), GFP_KERNEL); + if (info) { + ret = HYPERVISOR_xen_version(XENVER_compile_info, info); + if (!ret) + ret = sprintf(buffer, "%s\n", info->compiler); + kfree(info); + } + + return ret; +} + +HYPERVISOR_ATTR_RO(compiler); + +static ssize_t compiled_by_show(struct hyp_sysfs_attr *attr, char *buffer) +{ + int ret = -ENOMEM; + struct xen_compile_info *info; + + info = kmalloc(sizeof(struct xen_compile_info), GFP_KERNEL); + if (info) { + ret = HYPERVISOR_xen_version(XENVER_compile_info, info); + if (!ret) + ret = sprintf(buffer, "%s\n", info->compile_by); + kfree(info); + } + + return ret; +} + +HYPERVISOR_ATTR_RO(compiled_by); + +static ssize_t compile_date_show(struct hyp_sysfs_attr *attr, char *buffer) +{ + int ret = -ENOMEM; + struct xen_compile_info *info; + + info = kmalloc(sizeof(struct xen_compile_info), GFP_KERNEL); + if (info) { + ret = HYPERVISOR_xen_version(XENVER_compile_info, info); + if (!ret) + ret = sprintf(buffer, "%s\n", info->compile_date); + kfree(info); + } + + return ret; +} + +HYPERVISOR_ATTR_RO(compile_date); + +static struct attribute *xen_compile_attrs[] = { + &compiler_attr.attr, + &compiled_by_attr.attr, + &compile_date_attr.attr, + NULL +}; + +static struct attribute_group xen_compilation_group = { + .name = "compilation", + .attrs = xen_compile_attrs, +}; + +int __init static xen_compilation_init(void) +{ + return sysfs_create_group(hypervisor_kobj, &xen_compilation_group); +} + +static void xen_compilation_destroy(void) +{ + sysfs_remove_group(hypervisor_kobj, &xen_compilation_group); +} + +/* xen properties info */ + +static ssize_t capabilities_show(struct hyp_sysfs_attr *attr, char *buffer) +{ + int ret = -ENOMEM; + char *caps; + + caps = kmalloc(XEN_CAPABILITIES_INFO_LEN, GFP_KERNEL); + if (caps) { + ret = HYPERVISOR_xen_version(XENVER_capabilities, caps); + if (!ret) + ret = sprintf(buffer, "%s\n", caps); + kfree(caps); + } + + return ret; +} + +HYPERVISOR_ATTR_RO(capabilities); + +static ssize_t changeset_show(struct hyp_sysfs_attr *attr, char *buffer) +{ + int ret = -ENOMEM; + char *cset; + + cset = kmalloc(XEN_CHANGESET_INFO_LEN, GFP_KERNEL); + if (cset) { + ret = HYPERVISOR_xen_version(XENVER_changeset, cset); + if (!ret) + ret = sprintf(buffer, "%s\n", cset); + kfree(cset); + } + + return ret; +} + +HYPERVISOR_ATTR_RO(changeset); + +static ssize_t virtual_start_show(struct hyp_sysfs_attr *attr, char *buffer) +{ + int ret = -ENOMEM; + struct xen_platform_parameters *parms; + + parms = kmalloc(sizeof(struct xen_platform_parameters), GFP_KERNEL); + if (parms) { + ret = HYPERVISOR_xen_version(XENVER_platform_parameters, + parms); + if (!ret) + ret = sprintf(buffer, "%lx\n", parms->virt_start); + kfree(parms); + } + + return ret; +} + +HYPERVISOR_ATTR_RO(virtual_start); + +static ssize_t pagesize_show(struct hyp_sysfs_attr *attr, char *buffer) +{ + int ret; + + ret = HYPERVISOR_xen_version(XENVER_pagesize, NULL); + if (ret > 0) + ret = sprintf(buffer, "%x\n", ret); + + return ret; +} + +HYPERVISOR_ATTR_RO(pagesize); + +/* eventually there will be several more features to export */ +static ssize_t xen_feature_show(int index, char *buffer) +{ + int ret = -ENOMEM; + struct xen_feature_info *info; + + info = kmalloc(sizeof(struct xen_feature_info), GFP_KERNEL); + if (info) { + info->submap_idx = index; + ret = HYPERVISOR_xen_version(XENVER_get_features, info); + if (!ret) + ret = sprintf(buffer, "%d\n", info->submap); + kfree(info); + } + + return ret; +} + +static ssize_t writable_pt_show(struct hyp_sysfs_attr *attr, char *buffer) +{ + return xen_feature_show(XENFEAT_writable_page_tables, buffer); +} + +HYPERVISOR_ATTR_RO(writable_pt); + +static struct attribute *xen_properties_attrs[] = { + &capabilities_attr.attr, + &changeset_attr.attr, + &virtual_start_attr.attr, + &pagesize_attr.attr, + &writable_pt_attr.attr, + NULL +}; + +static struct attribute_group xen_properties_group = { + .name = "properties", + .attrs = xen_properties_attrs, +}; + +static int __init xen_properties_init(void) +{ + return sysfs_create_group(hypervisor_kobj, &xen_properties_group); +} + +static void xen_properties_destroy(void) +{ + sysfs_remove_group(hypervisor_kobj, &xen_properties_group); +} + +#ifdef CONFIG_KEXEC + +extern size_t vmcoreinfo_size_xen; +extern unsigned long paddr_vmcoreinfo_xen; + +static ssize_t vmcoreinfo_show(struct hyp_sysfs_attr *attr, char *page) +{ + return sprintf(page, "%lx %zx\n", + paddr_vmcoreinfo_xen, vmcoreinfo_size_xen); +} + +HYPERVISOR_ATTR_RO(vmcoreinfo); + +static int __init xen_sysfs_vmcoreinfo_init(void) +{ + return sysfs_create_file(hypervisor_kobj, + &vmcoreinfo_attr.attr); +} + +static void xen_sysfs_vmcoreinfo_destroy(void) +{ + sysfs_remove_file(hypervisor_kobj, &vmcoreinfo_attr.attr); +} + +#endif + +static int __init hyper_sysfs_init(void) +{ + int ret; + + if (!xen_domain()) + return -ENODEV; + + ret = xen_sysfs_type_init(); + if (ret) + goto out; + ret = xen_sysfs_version_init(); + if (ret) + goto version_out; + ret = xen_compilation_init(); + if (ret) + goto comp_out; + ret = xen_sysfs_uuid_init(); + if (ret) + goto uuid_out; + ret = xen_properties_init(); + if (ret) + goto prop_out; +#ifdef CONFIG_KEXEC + if (vmcoreinfo_size_xen != 0) { + ret = xen_sysfs_vmcoreinfo_init(); + if (ret) + goto vmcoreinfo_out; + } +#endif + + goto out; + +#ifdef CONFIG_KEXEC +vmcoreinfo_out: +#endif + xen_properties_destroy(); +prop_out: + xen_sysfs_uuid_destroy(); +uuid_out: + xen_compilation_destroy(); +comp_out: + xen_sysfs_version_destroy(); +version_out: + xen_sysfs_type_destroy(); +out: + return ret; +} + +static void __exit hyper_sysfs_exit(void) +{ +#ifdef CONFIG_KEXEC + if (vmcoreinfo_size_xen != 0) + xen_sysfs_vmcoreinfo_destroy(); +#endif + xen_properties_destroy(); + xen_compilation_destroy(); + xen_sysfs_uuid_destroy(); + xen_sysfs_version_destroy(); + xen_sysfs_type_destroy(); + +} +module_init(hyper_sysfs_init); +module_exit(hyper_sysfs_exit); + +static ssize_t hyp_sysfs_show(struct kobject *kobj, + struct attribute *attr, + char *buffer) +{ + struct hyp_sysfs_attr *hyp_attr; + hyp_attr = container_of(attr, struct hyp_sysfs_attr, attr); + if (hyp_attr->show) + return hyp_attr->show(hyp_attr, buffer); + return 0; +} + +static ssize_t hyp_sysfs_store(struct kobject *kobj, + struct attribute *attr, + const char *buffer, + size_t len) +{ + struct hyp_sysfs_attr *hyp_attr; + hyp_attr = container_of(attr, struct hyp_sysfs_attr, attr); + if (hyp_attr->store) + return hyp_attr->store(hyp_attr, buffer, len); + return 0; +} + +static struct sysfs_ops hyp_sysfs_ops = { + .show = hyp_sysfs_show, + .store = hyp_sysfs_store, +}; + +static struct kobj_type hyp_sysfs_kobj_type = { + .sysfs_ops = &hyp_sysfs_ops, +}; + +static int __init hypervisor_subsys_init(void) +{ + if (!xen_domain()) + return -ENODEV; + + hypervisor_kobj->ktype = &hyp_sysfs_kobj_type; + return 0; +} +device_initcall(hypervisor_subsys_init); diff --git a/include/xen/interface/version.h b/include/xen/interface/version.h index 453235e923f0..e8b6519d47e9 100644 --- a/include/xen/interface/version.h +++ b/include/xen/interface/version.h @@ -57,4 +57,7 @@ struct xen_feature_info { /* Declares the features reported by XENVER_get_features. */ #include "features.h" +/* arg == NULL; returns host memory page size. */ +#define XENVER_pagesize 7 + #endif /* __XEN_PUBLIC_VERSION_H__ */ -- cgit v1.2.3 From a649b720614d5675dc402bef75a92576143fede7 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Tue, 10 Mar 2009 17:17:41 -0700 Subject: xen/sys/hypervisor: change writable_pt to features /sys/hypervisor/properties/writable_pt was misnamed. Rename to features, expressed as a bit array in hex. Signed-off-by: Jeremy Fitzhardinge --- drivers/xen/sys-hypervisor.c | 41 ++++++++++++++++++++++++++--------------- 1 file changed, 26 insertions(+), 15 deletions(-) diff --git a/drivers/xen/sys-hypervisor.c b/drivers/xen/sys-hypervisor.c index cb29d1ccf0d9..1267d6fcc0c7 100644 --- a/drivers/xen/sys-hypervisor.c +++ b/drivers/xen/sys-hypervisor.c @@ -293,37 +293,48 @@ static ssize_t pagesize_show(struct hyp_sysfs_attr *attr, char *buffer) HYPERVISOR_ATTR_RO(pagesize); -/* eventually there will be several more features to export */ static ssize_t xen_feature_show(int index, char *buffer) { - int ret = -ENOMEM; - struct xen_feature_info *info; + ssize_t ret; + struct xen_feature_info info; - info = kmalloc(sizeof(struct xen_feature_info), GFP_KERNEL); - if (info) { - info->submap_idx = index; - ret = HYPERVISOR_xen_version(XENVER_get_features, info); - if (!ret) - ret = sprintf(buffer, "%d\n", info->submap); - kfree(info); - } + info.submap_idx = index; + ret = HYPERVISOR_xen_version(XENVER_get_features, &info); + if (!ret) + ret = sprintf(buffer, "%08x", info.submap); return ret; } -static ssize_t writable_pt_show(struct hyp_sysfs_attr *attr, char *buffer) +static ssize_t features_show(struct hyp_sysfs_attr *attr, char *buffer) { - return xen_feature_show(XENFEAT_writable_page_tables, buffer); + ssize_t len; + int i; + + len = 0; + for (i = XENFEAT_NR_SUBMAPS-1; i >= 0; i--) { + int ret = xen_feature_show(i, buffer + len); + if (ret < 0) { + if (len == 0) + len = ret; + break; + } + len += ret; + } + if (len > 0) + buffer[len++] = '\n'; + + return len; } -HYPERVISOR_ATTR_RO(writable_pt); +HYPERVISOR_ATTR_RO(features); static struct attribute *xen_properties_attrs[] = { &capabilities_attr.attr, &changeset_attr.attr, &virtual_start_attr.attr, &pagesize_attr.attr, - &writable_pt_attr.attr, + &features_attr.attr, NULL }; -- cgit v1.2.3 From f0783708bf63a2827863cf2be57c08a24843e6bd Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Wed, 11 Mar 2009 10:19:54 +0000 Subject: xen: drop kexec bits from /sys/hypervisor since kexec isn't implemented yet I needed this to compile since there is no kexec yet in pvops kernel CC drivers/xen/sys-hypervisor.o drivers/xen/sys-hypervisor.c: In function 'hyper_sysfs_init': drivers/xen/sys-hypervisor.c:405: error: 'vmcoreinfo_size_xen' undeclared (first use in this function) drivers/xen/sys-hypervisor.c:405: error: (Each undeclared identifier is reported only once drivers/xen/sys-hypervisor.c:405: error: for each function it appears in.) drivers/xen/sys-hypervisor.c:406: error: implicit declaration of function 'xen_sysfs_vmcoreinfo_init' drivers/xen/sys-hypervisor.c: In function 'hyper_sysfs_exit': drivers/xen/sys-hypervisor.c:433: error: 'vmcoreinfo_size_xen' undeclared (first use in this function) drivers/xen/sys-hypervisor.c:434: error: implicit declaration of function 'xen_sysfs_vmcoreinfo_destroy' Signed-off-by: Ian Campbell --- drivers/xen/sys-hypervisor.c | 41 ----------------------------------------- 1 file changed, 41 deletions(-) diff --git a/drivers/xen/sys-hypervisor.c b/drivers/xen/sys-hypervisor.c index 1267d6fcc0c7..88a60e03ccf0 100644 --- a/drivers/xen/sys-hypervisor.c +++ b/drivers/xen/sys-hypervisor.c @@ -353,32 +353,6 @@ static void xen_properties_destroy(void) sysfs_remove_group(hypervisor_kobj, &xen_properties_group); } -#ifdef CONFIG_KEXEC - -extern size_t vmcoreinfo_size_xen; -extern unsigned long paddr_vmcoreinfo_xen; - -static ssize_t vmcoreinfo_show(struct hyp_sysfs_attr *attr, char *page) -{ - return sprintf(page, "%lx %zx\n", - paddr_vmcoreinfo_xen, vmcoreinfo_size_xen); -} - -HYPERVISOR_ATTR_RO(vmcoreinfo); - -static int __init xen_sysfs_vmcoreinfo_init(void) -{ - return sysfs_create_file(hypervisor_kobj, - &vmcoreinfo_attr.attr); -} - -static void xen_sysfs_vmcoreinfo_destroy(void) -{ - sysfs_remove_file(hypervisor_kobj, &vmcoreinfo_attr.attr); -} - -#endif - static int __init hyper_sysfs_init(void) { int ret; @@ -401,20 +375,9 @@ static int __init hyper_sysfs_init(void) ret = xen_properties_init(); if (ret) goto prop_out; -#ifdef CONFIG_KEXEC - if (vmcoreinfo_size_xen != 0) { - ret = xen_sysfs_vmcoreinfo_init(); - if (ret) - goto vmcoreinfo_out; - } -#endif goto out; -#ifdef CONFIG_KEXEC -vmcoreinfo_out: -#endif - xen_properties_destroy(); prop_out: xen_sysfs_uuid_destroy(); uuid_out: @@ -429,10 +392,6 @@ out: static void __exit hyper_sysfs_exit(void) { -#ifdef CONFIG_KEXEC - if (vmcoreinfo_size_xen != 0) - xen_sysfs_vmcoreinfo_destroy(); -#endif xen_properties_destroy(); xen_compilation_destroy(); xen_sysfs_uuid_destroy(); -- cgit v1.2.3 From 818fd20673df82031e604bb784d836f1fc2e2451 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Fri, 6 Feb 2009 18:46:47 -0800 Subject: xen: add "capabilities" file The xenfs capabilities file allows usermode to determine what capabilities the domain has. The only one at present is "control_d" in a privileged domain. Signed-off-by: Jeremy Fitzhardinge --- drivers/xen/xenfs/super.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/drivers/xen/xenfs/super.c b/drivers/xen/xenfs/super.c index 515741a8e6b8..6559e0c752ce 100644 --- a/drivers/xen/xenfs/super.c +++ b/drivers/xen/xenfs/super.c @@ -20,10 +20,27 @@ MODULE_DESCRIPTION("Xen filesystem"); MODULE_LICENSE("GPL"); +static ssize_t capabilities_read(struct file *file, char __user *buf, + size_t size, loff_t *off) +{ + char *tmp = ""; + + if (xen_initial_domain()) + tmp = "control_d\n"; + + return simple_read_from_buffer(buf, size, off, tmp, strlen(tmp)); +} + +static const struct file_operations capabilities_file_ops = { + .read = capabilities_read, +}; + static int xenfs_fill_super(struct super_block *sb, void *data, int silent) { static struct tree_descr xenfs_files[] = { - [2] = {"xenbus", &xenbus_file_ops, S_IRUSR|S_IWUSR}, + [1] = {}, + { "xenbus", &xenbus_file_ops, S_IRUSR|S_IWUSR }, + { "capabilities", &capabilities_file_ops, S_IRUGO }, {""}, }; -- cgit v1.2.3 From 53152f957d4a5dfd537d17c823afeb1a2c03753e Mon Sep 17 00:00:00 2001 From: Ian Campbell Date: Thu, 2 Apr 2009 13:24:28 +0100 Subject: xen: honour VCPU availability on boot If a VM is booted with offline VCPUs then unplug them during boot. Determining the availability of a VCPU requires access to XenStore which is not available at the point smp_prepare_cpus() is called, therefore we bring up all VCPUS initially and unplug the offline ones as soon as XenStore becomes available. Signed-off-by: Ian Campbell --- drivers/xen/cpu_hotplug.c | 40 ++++++++++++++++++++++++++++++---------- 1 file changed, 30 insertions(+), 10 deletions(-) diff --git a/drivers/xen/cpu_hotplug.c b/drivers/xen/cpu_hotplug.c index 974f56d1ebe1..411cb1fc9279 100644 --- a/drivers/xen/cpu_hotplug.c +++ b/drivers/xen/cpu_hotplug.c @@ -21,29 +21,41 @@ static void disable_hotplug_cpu(int cpu) cpu_clear(cpu, cpu_present_map); } -static void vcpu_hotplug(unsigned int cpu) +static int vcpu_online(unsigned int cpu) { int err; char dir[32], state[32]; - if (!cpu_possible(cpu)) - return; - sprintf(dir, "cpu/%u", cpu); err = xenbus_scanf(XBT_NIL, dir, "availability", "%s", state); if (err != 1) { printk(KERN_ERR "XENBUS: Unable to read cpu state\n"); - return; + return err; } - if (strcmp(state, "online") == 0) { + if (strcmp(state, "online") == 0) + return 1; + else if (strcmp(state, "offline") == 0) + return 0; + + printk(KERN_ERR "XENBUS: unknown state(%s) on CPU%d\n", state, cpu); + return -EINVAL; +} +static void vcpu_hotplug(unsigned int cpu) +{ + if (!cpu_possible(cpu)) + return; + + switch (vcpu_online(cpu)) { + case 1: enable_hotplug_cpu(cpu); - } else if (strcmp(state, "offline") == 0) { + break; + case 0: (void)cpu_down(cpu); disable_hotplug_cpu(cpu); - } else { - printk(KERN_ERR "XENBUS: unknown state(%s) on CPU%d\n", - state, cpu); + break; + default: + break; } } @@ -64,12 +76,20 @@ static void handle_vcpu_hotplug_event(struct xenbus_watch *watch, static int setup_cpu_watcher(struct notifier_block *notifier, unsigned long event, void *data) { + int cpu; static struct xenbus_watch cpu_watch = { .node = "cpu", .callback = handle_vcpu_hotplug_event}; (void)register_xenbus_watch(&cpu_watch); + for_each_possible_cpu(cpu) { + if (vcpu_online(cpu) == 0) { + (void)cpu_down(cpu); + cpu_clear(cpu, cpu_present_map); + } + } + return NOTIFY_DONE; } -- cgit v1.2.3 From 169aafbc8d3f05431b5cfeb60294a12b8ef2bcee Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Tue, 7 Apr 2009 13:37:26 -0700 Subject: lguest: update lazy mmu changes to match lguest's use of kvm hypercalls Duplicate hcall -> kvm_hypercall0 convertion from "lguest: use KVM hypercalls". Signed-off-by: Jeremy Fitzhardinge Cc: Matias Zabaljauregui Cc: Rusty Russell --- arch/x86/lguest/boot.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c index 5ab239711cc2..cfb2d68dc795 100644 --- a/arch/x86/lguest/boot.c +++ b/arch/x86/lguest/boot.c @@ -168,7 +168,7 @@ static void lazy_hcall3(unsigned long call, * issue the do-nothing hypercall to flush any stored calls. */ static void lguest_leave_lazy_mmu_mode(void) { - hcall(LHCALL_FLUSH_ASYNC, 0, 0, 0); + kvm_hypercall0(LHCALL_FLUSH_ASYNC); paravirt_leave_lazy_mmu(); } -- cgit v1.2.3 From e7c064889606aab3569669078c69b87b2c527e72 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Sat, 7 Mar 2009 23:48:41 -0800 Subject: xen: add FIX_TEXT_POKE to fixmap FIX_TEXT_POKE[01] are used to map kernel addresses, so they're mapping pfns, not mfns. Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/mmu.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 77b242c9a11e..a96f5b9393ea 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -1812,6 +1812,9 @@ static void xen_set_fixmap(unsigned idx, unsigned long phys, pgprot_t prot) #ifdef CONFIG_X86_LOCAL_APIC case FIX_APIC_BASE: /* maps dummy local APIC */ #endif + case FIX_TEXT_POKE0: + case FIX_TEXT_POKE1: + /* All local page mappings */ pte = pfn_pte(phys, prot); break; -- cgit v1.2.3 From 6b2e8523df148c15ea5abf13075026fb8bdb3f86 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Thu, 7 May 2009 11:56:49 -0700 Subject: xen: reserve Xen start_info rather than e820 reserving Use reserve_early rather than e820 reservations for Xen start info and mfn->pfn table, so that the memory use is a bit more self-documenting. [ Impact: cleanup ] Signed-off-by: Jeremy Fitzhardinge Cc: Xen-devel Cc: Linus Torvalds LKML-Reference: <4A032EF1.6070708@goop.org> Signed-off-by: Ingo Molnar --- arch/x86/xen/setup.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c index 15c6c68db6a2..ad0047f47cd4 100644 --- a/arch/x86/xen/setup.c +++ b/arch/x86/xen/setup.c @@ -61,9 +61,9 @@ char * __init xen_memory_setup(void) * - xen_start_info * See comment above "struct start_info" in */ - e820_add_region(__pa(xen_start_info->mfn_list), - xen_start_info->pt_base - xen_start_info->mfn_list, - E820_RESERVED); + reserve_early(__pa(xen_start_info->mfn_list), + __pa(xen_start_info->pt_base), + "XEN START INFO"); sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map); -- cgit v1.2.3 From 6cac5a924668a56c7ccefc345805f1fe0536a90e Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Sun, 29 Mar 2009 19:56:29 -0700 Subject: xen/x86-64: fix breakpoints and hardware watchpoints Native x86-64 uses the IST mechanism to run int3 and debug traps on an alternative stack. Xen does not do this, and so the frames were being misinterpreted by the ptrace code. This change special-cases these two exceptions by using Xen variants which run on the normal kernel stack properly. Impact: avoid crash or bad data when IST trap is invoked under Xen Signed-off-by: Jeremy Fitzhardinge --- arch/x86/include/asm/traps.h | 3 +++ arch/x86/kernel/entry_64.S | 5 +++++ arch/x86/xen/enlighten.c | 19 ++++++++++++++++++- 3 files changed, 26 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/traps.h b/arch/x86/include/asm/traps.h index 0d5342515b86..c44e5002f2ff 100644 --- a/arch/x86/include/asm/traps.h +++ b/arch/x86/include/asm/traps.h @@ -13,6 +13,9 @@ asmlinkage void divide_error(void); asmlinkage void debug(void); asmlinkage void nmi(void); asmlinkage void int3(void); +asmlinkage void xen_debug(void); +asmlinkage void xen_int3(void); +asmlinkage void xen_stack_segment(void); asmlinkage void overflow(void); asmlinkage void bounds(void); asmlinkage void invalid_op(void); diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index 38946c6e8433..bb01ce080b80 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -1379,6 +1379,11 @@ END(xen_failsafe_callback) paranoidzeroentry_ist debug do_debug DEBUG_STACK paranoidzeroentry_ist int3 do_int3 DEBUG_STACK paranoiderrorentry stack_segment do_stack_segment +#ifdef CONFIG_XEN +zeroentry xen_debug do_debug +zeroentry xen_int3 do_int3 +errorentry xen_stack_segment do_stack_segment +#endif errorentry general_protection do_general_protection errorentry page_fault do_page_fault #ifdef CONFIG_X86_MCE diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 12a3159333bc..7566e13c0cac 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include #include @@ -44,6 +45,7 @@ #include #include #include +#include #include #include #include @@ -428,11 +430,26 @@ static void xen_write_ldt_entry(struct desc_struct *dt, int entrynum, static int cvt_gate_to_trap(int vector, const gate_desc *val, struct trap_info *info) { + unsigned long addr; + if (val->type != GATE_TRAP && val->type != GATE_INTERRUPT) return 0; info->vector = vector; - info->address = gate_offset(*val); + + addr = gate_offset(*val); +#ifdef CONFIG_X86_64 + if (addr == (unsigned long)debug) + addr = (unsigned long)xen_debug; + else if (addr == (unsigned long)int3) + addr = (unsigned long)xen_int3; + else if (addr == (unsigned long)stack_segment) + addr = (unsigned long)xen_stack_segment; + else + WARN_ON(val->ist != 0); +#endif /* CONFIG_X86_64 */ + info->address = addr; + info->cs = gate_segment(*val); info->flags = val->dpl; /* interrupt gates clear IF */ -- cgit v1.2.3 From b80119bb35a49a4e8dbfb9708872adfd5cf38dee Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Fri, 24 Apr 2009 00:22:08 -0700 Subject: xen/x86-64: clean up warnings about IST-using traps Ignore known IST-using traps. Aside from the debugger traps, they're low-level faults which Xen will handle for us, so the kernel needn't worry about them. Keep warning in case unknown trap starts using IST. Impact: suppress spurious warnings Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/enlighten.c | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 7566e13c0cac..e9df942aa143 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -439,14 +439,32 @@ static int cvt_gate_to_trap(int vector, const gate_desc *val, addr = gate_offset(*val); #ifdef CONFIG_X86_64 + /* + * Look for known traps using IST, and substitute them + * appropriately. The debugger ones are the only ones we care + * about. Xen will handle faults like double_fault and + * machine_check, so we should never see them. Warn if + * there's an unexpected IST-using fault handler. + */ if (addr == (unsigned long)debug) addr = (unsigned long)xen_debug; else if (addr == (unsigned long)int3) addr = (unsigned long)xen_int3; else if (addr == (unsigned long)stack_segment) addr = (unsigned long)xen_stack_segment; - else - WARN_ON(val->ist != 0); + else if (addr == (unsigned long)double_fault || + addr == (unsigned long)nmi) { + /* Don't need to handle these */ + return 0; +#ifdef CONFIG_X86_MCE + } else if (addr == (unsigned long)machine_check) { + return 0; +#endif + } else { + /* Some other trap using IST? */ + if (WARN_ON(val->ist != 0)) + return 0; + } #endif /* CONFIG_X86_64 */ info->address = addr; -- cgit v1.2.3 From a789ed5fb6d0256c4177c2cc27e06520ddbe4d4c Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Fri, 24 Apr 2009 00:26:50 -0700 Subject: xen: cache cr0 value to avoid trap'n'emulate for read_cr0 stts() is implemented in terms of read_cr0/write_cr0 to update the state of the TS bit. This happens during context switch, and so is fairly performance critical. Rather than falling back to a trap-and-emulate native read_cr0, implement our own by caching the last-written value from write_cr0 (the TS bit is the only one we really care about). Impact: optimise Xen context switches Signed-off-by: Jeremy Fitzhardinge --- arch/x86/xen/enlighten.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index e9df942aa143..0a1700a2be9c 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -658,10 +658,26 @@ static void xen_clts(void) xen_mc_issue(PARAVIRT_LAZY_CPU); } +static DEFINE_PER_CPU(unsigned long, xen_cr0_value); + +static unsigned long xen_read_cr0(void) +{ + unsigned long cr0 = percpu_read(xen_cr0_value); + + if (unlikely(cr0 == 0)) { + cr0 = native_read_cr0(); + percpu_write(xen_cr0_value, cr0); + } + + return cr0; +} + static void xen_write_cr0(unsigned long cr0) { struct multicall_space mcs; + percpu_write(xen_cr0_value, cr0); + /* Only pay attention to cr0.TS; everything else is ignored. */ mcs = xen_mc_entry(0); @@ -847,7 +863,7 @@ static const struct pv_cpu_ops xen_cpu_ops __initdata = { .clts = xen_clts, - .read_cr0 = native_read_cr0, + .read_cr0 = xen_read_cr0, .write_cr0 = xen_write_cr0, .read_cr4 = native_read_cr4, -- cgit v1.2.3