| Message ID | 1415930268-7674-4-git-send-email-m.smarduch@samsung.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Paolo, I changed your patch a little to use a Kconfig symbol, hope that's fine with you. - Mario On 11/13/2014 05:57 PM, Mario Smarduch wrote: > From: Paolo Bonzini <pbonzini@redhat.com> > > We now have a generic function that does most of the work of > kvm_vm_ioctl_get_dirty_log, now use it. > > Signed-off-by: Mario Smarduch <m.smarduch@samsung.com> > --- > arch/x86/include/asm/kvm_host.h | 3 -- > arch/x86/kvm/Kconfig | 1 + > arch/x86/kvm/mmu.c | 4 +-- > arch/x86/kvm/x86.c | 64 ++++++--------------------------------- > 4 files changed, 12 insertions(+), 60 deletions(-) > > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index 7c492ed..934dc24 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -805,9 +805,6 @@ void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask, > > void kvm_mmu_reset_context(struct kvm_vcpu *vcpu); > void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot); > -void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, > - struct kvm_memory_slot *slot, > - gfn_t gfn_offset, unsigned long mask); > void kvm_mmu_zap_all(struct kvm *kvm); > void kvm_mmu_invalidate_mmio_sptes(struct kvm *kvm); > unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm); > diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig > index f9d16ff..d073594 100644 > --- a/arch/x86/kvm/Kconfig > +++ b/arch/x86/kvm/Kconfig > @@ -39,6 +39,7 @@ config KVM > select PERF_EVENTS > select HAVE_KVM_MSI > select HAVE_KVM_CPU_RELAX_INTERCEPT > + select KVM_GENERIC_DIRTYLOG_READ_PROTECT > select KVM_VFIO > ---help--- > Support hosting fully virtualized guest machines using hardware > diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c > index 9314678..bf6b82c 100644 > --- a/arch/x86/kvm/mmu.c > +++ b/arch/x86/kvm/mmu.c > @@ -1224,7 +1224,7 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, > } > > /** > - * kvm_mmu_write_protect_pt_masked - write protect selected PT level pages > + * kvm_arch_mmu_write_protect_pt_masked - write protect selected PT level pages > * @kvm: kvm instance > * @slot: slot to protect > * @gfn_offset: start of the BITS_PER_LONG pages we care about > @@ -1233,7 +1233,7 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, > * Used when we do not need to care about huge page mappings: e.g. during dirty > * logging we do not have any such mappings. > */ > -void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, > +void kvm_arch_mmu_write_protect_pt_masked(struct kvm *kvm, > struct kvm_memory_slot *slot, > gfn_t gfn_offset, unsigned long mask) > { > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 8f1e22d..9f8ae9a 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -3606,77 +3606,31 @@ static int kvm_vm_ioctl_reinject(struct kvm *kvm, > * > * 1. Take a snapshot of the bit and clear it if needed. > * 2. Write protect the corresponding page. > - * 3. Flush TLB's if needed. > - * 4. Copy the snapshot to the userspace. > + * 3. Copy the snapshot to the userspace. > + * 4. Flush TLB's if needed. > * > - * Between 2 and 3, the guest may write to the page using the remaining TLB > - * entry. This is not a problem because the page will be reported dirty at > - * step 4 using the snapshot taken before and step 3 ensures that successive > - * writes will be logged for the next call. > + * Between 2 and 4, the guest may write to the page using the remaining TLB > + * entry. This is not a problem because the page is reported dirty using > + * the snapshot taken before and step 4 ensures that writes done after > + * exiting to userspace will be logged for the next call. > */ > int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log) > { > - int r; > - struct kvm_memory_slot *memslot; > - unsigned long n, i; > - unsigned long *dirty_bitmap; > - unsigned long *dirty_bitmap_buffer; > bool is_dirty = false; > + int r; > > mutex_lock(&kvm->slots_lock); > > - r = -EINVAL; > - if (log->slot >= KVM_USER_MEM_SLOTS) > - goto out; > - > - memslot = id_to_memslot(kvm->memslots, log->slot); > - > - dirty_bitmap = memslot->dirty_bitmap; > - r = -ENOENT; > - if (!dirty_bitmap) > - goto out; > - > - n = kvm_dirty_bitmap_bytes(memslot); > - > - dirty_bitmap_buffer = dirty_bitmap + n / sizeof(long); > - memset(dirty_bitmap_buffer, 0, n); > - > - spin_lock(&kvm->mmu_lock); > - > - for (i = 0; i < n / sizeof(long); i++) { > - unsigned long mask; > - gfn_t offset; > - > - if (!dirty_bitmap[i]) > - continue; > - > - is_dirty = true; > - > - mask = xchg(&dirty_bitmap[i], 0); > - dirty_bitmap_buffer[i] = mask; > - > - offset = i * BITS_PER_LONG; > - kvm_mmu_write_protect_pt_masked(kvm, memslot, offset, mask); > - } > - > - spin_unlock(&kvm->mmu_lock); > - > - /* See the comments in kvm_mmu_slot_remove_write_access(). */ > - lockdep_assert_held(&kvm->slots_lock); > + r = kvm_get_dirty_log_protect(kvm, log, &is_dirty); > > /* > * All the TLBs can be flushed out of mmu lock, see the comments in > * kvm_mmu_slot_remove_write_access(). > */ > + lockdep_assert_held(&kvm->slots_lock); > if (is_dirty) > kvm_flush_remote_tlbs(kvm); > > - r = -EFAULT; > - if (copy_to_user(log->dirty_bitmap, dirty_bitmap_buffer, n)) > - goto out; > - > - r = 0; > -out: > mutex_unlock(&kvm->slots_lock); > return r; > } > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 14/11/2014 03:06, Mario Smarduch wrote: > Hi Paolo, > > I changed your patch a little to use a Kconfig symbol, > hope that's fine with you. Of course, thanks. Paolo > - Mario > > On 11/13/2014 05:57 PM, Mario Smarduch wrote: >> From: Paolo Bonzini <pbonzini@redhat.com> >> >> We now have a generic function that does most of the work of >> kvm_vm_ioctl_get_dirty_log, now use it. >> >> Signed-off-by: Mario Smarduch <m.smarduch@samsung.com> >> --- >> arch/x86/include/asm/kvm_host.h | 3 -- >> arch/x86/kvm/Kconfig | 1 + >> arch/x86/kvm/mmu.c | 4 +-- >> arch/x86/kvm/x86.c | 64 ++++++--------------------------------- >> 4 files changed, 12 insertions(+), 60 deletions(-) >> >> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h >> index 7c492ed..934dc24 100644 >> --- a/arch/x86/include/asm/kvm_host.h >> +++ b/arch/x86/include/asm/kvm_host.h >> @@ -805,9 +805,6 @@ void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask, >> >> void kvm_mmu_reset_context(struct kvm_vcpu *vcpu); >> void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot); >> -void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, >> - struct kvm_memory_slot *slot, >> - gfn_t gfn_offset, unsigned long mask); >> void kvm_mmu_zap_all(struct kvm *kvm); >> void kvm_mmu_invalidate_mmio_sptes(struct kvm *kvm); >> unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm); >> diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig >> index f9d16ff..d073594 100644 >> --- a/arch/x86/kvm/Kconfig >> +++ b/arch/x86/kvm/Kconfig >> @@ -39,6 +39,7 @@ config KVM >> select PERF_EVENTS >> select HAVE_KVM_MSI >> select HAVE_KVM_CPU_RELAX_INTERCEPT >> + select KVM_GENERIC_DIRTYLOG_READ_PROTECT >> select KVM_VFIO >> ---help--- >> Support hosting fully virtualized guest machines using hardware >> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c >> index 9314678..bf6b82c 100644 >> --- a/arch/x86/kvm/mmu.c >> +++ b/arch/x86/kvm/mmu.c >> @@ -1224,7 +1224,7 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, >> } >> >> /** >> - * kvm_mmu_write_protect_pt_masked - write protect selected PT level pages >> + * kvm_arch_mmu_write_protect_pt_masked - write protect selected PT level pages >> * @kvm: kvm instance >> * @slot: slot to protect >> * @gfn_offset: start of the BITS_PER_LONG pages we care about >> @@ -1233,7 +1233,7 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, >> * Used when we do not need to care about huge page mappings: e.g. during dirty >> * logging we do not have any such mappings. >> */ >> -void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, >> +void kvm_arch_mmu_write_protect_pt_masked(struct kvm *kvm, >> struct kvm_memory_slot *slot, >> gfn_t gfn_offset, unsigned long mask) >> { >> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c >> index 8f1e22d..9f8ae9a 100644 >> --- a/arch/x86/kvm/x86.c >> +++ b/arch/x86/kvm/x86.c >> @@ -3606,77 +3606,31 @@ static int kvm_vm_ioctl_reinject(struct kvm *kvm, >> * >> * 1. Take a snapshot of the bit and clear it if needed. >> * 2. Write protect the corresponding page. >> - * 3. Flush TLB's if needed. >> - * 4. Copy the snapshot to the userspace. >> + * 3. Copy the snapshot to the userspace. >> + * 4. Flush TLB's if needed. >> * >> - * Between 2 and 3, the guest may write to the page using the remaining TLB >> - * entry. This is not a problem because the page will be reported dirty at >> - * step 4 using the snapshot taken before and step 3 ensures that successive >> - * writes will be logged for the next call. >> + * Between 2 and 4, the guest may write to the page using the remaining TLB >> + * entry. This is not a problem because the page is reported dirty using >> + * the snapshot taken before and step 4 ensures that writes done after >> + * exiting to userspace will be logged for the next call. >> */ >> int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log) >> { >> - int r; >> - struct kvm_memory_slot *memslot; >> - unsigned long n, i; >> - unsigned long *dirty_bitmap; >> - unsigned long *dirty_bitmap_buffer; >> bool is_dirty = false; >> + int r; >> >> mutex_lock(&kvm->slots_lock); >> >> - r = -EINVAL; >> - if (log->slot >= KVM_USER_MEM_SLOTS) >> - goto out; >> - >> - memslot = id_to_memslot(kvm->memslots, log->slot); >> - >> - dirty_bitmap = memslot->dirty_bitmap; >> - r = -ENOENT; >> - if (!dirty_bitmap) >> - goto out; >> - >> - n = kvm_dirty_bitmap_bytes(memslot); >> - >> - dirty_bitmap_buffer = dirty_bitmap + n / sizeof(long); >> - memset(dirty_bitmap_buffer, 0, n); >> - >> - spin_lock(&kvm->mmu_lock); >> - >> - for (i = 0; i < n / sizeof(long); i++) { >> - unsigned long mask; >> - gfn_t offset; >> - >> - if (!dirty_bitmap[i]) >> - continue; >> - >> - is_dirty = true; >> - >> - mask = xchg(&dirty_bitmap[i], 0); >> - dirty_bitmap_buffer[i] = mask; >> - >> - offset = i * BITS_PER_LONG; >> - kvm_mmu_write_protect_pt_masked(kvm, memslot, offset, mask); >> - } >> - >> - spin_unlock(&kvm->mmu_lock); >> - >> - /* See the comments in kvm_mmu_slot_remove_write_access(). */ >> - lockdep_assert_held(&kvm->slots_lock); >> + r = kvm_get_dirty_log_protect(kvm, log, &is_dirty); >> >> /* >> * All the TLBs can be flushed out of mmu lock, see the comments in >> * kvm_mmu_slot_remove_write_access(). >> */ >> + lockdep_assert_held(&kvm->slots_lock); >> if (is_dirty) >> kvm_flush_remote_tlbs(kvm); >> >> - r = -EFAULT; >> - if (copy_to_user(log->dirty_bitmap, dirty_bitmap_buffer, n)) >> - goto out; >> - >> - r = 0; >> -out: >> mutex_unlock(&kvm->slots_lock); >> return r; >> } >> > > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Nov 13, 2014 at 05:57:44PM -0800, Mario Smarduch wrote: > From: Paolo Bonzini <pbonzini@redhat.com> > > We now have a generic function that does most of the work of > kvm_vm_ioctl_get_dirty_log, now use it. > > Signed-off-by: Mario Smarduch <m.smarduch@samsung.com> > --- > arch/x86/include/asm/kvm_host.h | 3 -- > arch/x86/kvm/Kconfig | 1 + > arch/x86/kvm/mmu.c | 4 +-- > arch/x86/kvm/x86.c | 64 ++++++--------------------------------- > 4 files changed, 12 insertions(+), 60 deletions(-) > > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index 7c492ed..934dc24 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -805,9 +805,6 @@ void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask, > > void kvm_mmu_reset_context(struct kvm_vcpu *vcpu); > void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot); > -void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, > - struct kvm_memory_slot *slot, > - gfn_t gfn_offset, unsigned long mask); > void kvm_mmu_zap_all(struct kvm *kvm); > void kvm_mmu_invalidate_mmio_sptes(struct kvm *kvm); > unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm); > diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig > index f9d16ff..d073594 100644 > --- a/arch/x86/kvm/Kconfig > +++ b/arch/x86/kvm/Kconfig > @@ -39,6 +39,7 @@ config KVM > select PERF_EVENTS > select HAVE_KVM_MSI > select HAVE_KVM_CPU_RELAX_INTERCEPT > + select KVM_GENERIC_DIRTYLOG_READ_PROTECT > select KVM_VFIO > ---help--- > Support hosting fully virtualized guest machines using hardware > diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c > index 9314678..bf6b82c 100644 > --- a/arch/x86/kvm/mmu.c > +++ b/arch/x86/kvm/mmu.c > @@ -1224,7 +1224,7 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, > } > > /** > - * kvm_mmu_write_protect_pt_masked - write protect selected PT level pages > + * kvm_arch_mmu_write_protect_pt_masked - write protect selected PT level pages > * @kvm: kvm instance > * @slot: slot to protect > * @gfn_offset: start of the BITS_PER_LONG pages we care about > @@ -1233,7 +1233,7 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, > * Used when we do not need to care about huge page mappings: e.g. during dirty > * logging we do not have any such mappings. > */ > -void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, > +void kvm_arch_mmu_write_protect_pt_masked(struct kvm *kvm, > struct kvm_memory_slot *slot, > gfn_t gfn_offset, unsigned long mask) > { > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 8f1e22d..9f8ae9a 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -3606,77 +3606,31 @@ static int kvm_vm_ioctl_reinject(struct kvm *kvm, > * > * 1. Take a snapshot of the bit and clear it if needed. > * 2. Write protect the corresponding page. > - * 3. Flush TLB's if needed. > - * 4. Copy the snapshot to the userspace. > + * 3. Copy the snapshot to the userspace. > + * 4. Flush TLB's if needed. > * > - * Between 2 and 3, the guest may write to the page using the remaining TLB > - * entry. This is not a problem because the page will be reported dirty at > - * step 4 using the snapshot taken before and step 3 ensures that successive > - * writes will be logged for the next call. > + * Between 2 and 4, the guest may write to the page using the remaining TLB > + * entry. This is not a problem because the page is reported dirty using > + * the snapshot taken before and step 4 ensures that writes done after > + * exiting to userspace will be logged for the next call. > */ this seems to duplicate the comment in virt/kvm/kvm_main.c, but whatever. FWIW: Acked-by: Christoffer Dall <christoffer.dall@linaro.org> -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 11/22/2014 11:19 AM, Christoffer Dall wrote: > On Thu, Nov 13, 2014 at 05:57:44PM -0800, Mario Smarduch wrote: >> From: Paolo Bonzini <pbonzini@redhat.com> >> >> We now have a generic function that does most of the work of >> kvm_vm_ioctl_get_dirty_log, now use it. >> >> Signed-off-by: Mario Smarduch <m.smarduch@samsung.com> >> --- >> arch/x86/include/asm/kvm_host.h | 3 -- >> arch/x86/kvm/Kconfig | 1 + >> arch/x86/kvm/mmu.c | 4 +-- >> arch/x86/kvm/x86.c | 64 ++++++--------------------------------- >> 4 files changed, 12 insertions(+), 60 deletions(-) >> >> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h >> index 7c492ed..934dc24 100644 >> --- a/arch/x86/include/asm/kvm_host.h >> +++ b/arch/x86/include/asm/kvm_host.h >> @@ -805,9 +805,6 @@ void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask, >> >> void kvm_mmu_reset_context(struct kvm_vcpu *vcpu); >> void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot); >> -void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, >> - struct kvm_memory_slot *slot, >> - gfn_t gfn_offset, unsigned long mask); >> void kvm_mmu_zap_all(struct kvm *kvm); >> void kvm_mmu_invalidate_mmio_sptes(struct kvm *kvm); >> unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm); >> diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig >> index f9d16ff..d073594 100644 >> --- a/arch/x86/kvm/Kconfig >> +++ b/arch/x86/kvm/Kconfig >> @@ -39,6 +39,7 @@ config KVM >> select PERF_EVENTS >> select HAVE_KVM_MSI >> select HAVE_KVM_CPU_RELAX_INTERCEPT >> + select KVM_GENERIC_DIRTYLOG_READ_PROTECT >> select KVM_VFIO >> ---help--- >> Support hosting fully virtualized guest machines using hardware >> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c >> index 9314678..bf6b82c 100644 >> --- a/arch/x86/kvm/mmu.c >> +++ b/arch/x86/kvm/mmu.c >> @@ -1224,7 +1224,7 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, >> } >> >> /** >> - * kvm_mmu_write_protect_pt_masked - write protect selected PT level pages >> + * kvm_arch_mmu_write_protect_pt_masked - write protect selected PT level pages >> * @kvm: kvm instance >> * @slot: slot to protect >> * @gfn_offset: start of the BITS_PER_LONG pages we care about >> @@ -1233,7 +1233,7 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, >> * Used when we do not need to care about huge page mappings: e.g. during dirty >> * logging we do not have any such mappings. >> */ >> -void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, >> +void kvm_arch_mmu_write_protect_pt_masked(struct kvm *kvm, >> struct kvm_memory_slot *slot, >> gfn_t gfn_offset, unsigned long mask) >> { >> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c >> index 8f1e22d..9f8ae9a 100644 >> --- a/arch/x86/kvm/x86.c >> +++ b/arch/x86/kvm/x86.c >> @@ -3606,77 +3606,31 @@ static int kvm_vm_ioctl_reinject(struct kvm *kvm, >> * >> * 1. Take a snapshot of the bit and clear it if needed. >> * 2. Write protect the corresponding page. >> - * 3. Flush TLB's if needed. >> - * 4. Copy the snapshot to the userspace. >> + * 3. Copy the snapshot to the userspace. >> + * 4. Flush TLB's if needed. >> * >> - * Between 2 and 3, the guest may write to the page using the remaining TLB >> - * entry. This is not a problem because the page will be reported dirty at >> - * step 4 using the snapshot taken before and step 3 ensures that successive >> - * writes will be logged for the next call. >> + * Between 2 and 4, the guest may write to the page using the remaining TLB >> + * entry. This is not a problem because the page is reported dirty using >> + * the snapshot taken before and step 4 ensures that writes done after >> + * exiting to userspace will be logged for the next call. >> */ > > this seems to duplicate the comment in virt/kvm/kvm_main.c, but > whatever. Reuses most of that text but differs slightly, the _protect version is a subset of this one. > > FWIW: > Acked-by: Christoffer Dall <christoffer.dall@linaro.org> > Thanks. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Paolo, I took a closer look at Christoffers comment, the _log description in x86.c is a repeat of the _protect description in kvm_main.c. I'm wondering if description below would be acceptable, or perhaps you had a reason leaving it as is. For the ARM variant I would word same. Please advise. Thanks. " /** * kvm_vm_ioctl_get_dirty_log - get and clear the log of dirty pages in a slot * @kvm: kvm instance * @log: slot id and address to which we copy the log * * Steps 1-4 below provide general overview of dirty page logging. See * kvm_get_dirty_log_protect() function description for additional details. * * We call kvm_get_dirty_log_protect() to handle steps 1-3, upon return we * always flush the TLB (step 4) even if 'protect' failed and dirty bitmap * may be corrupt. Regardless of previous outcome KVM logging API does not * preclude user space subsequent dirty log read. Flushing TLB insures writes * will be marked dirty for next log read. * * 1. Take a snapshot of the bit and clear it if needed. * 2. Write protect the corresponding page. * 3. Copy the snapshot to the userspace. * 4. Flush TLB's if needed. */ " On 11/22/2014 11:19 AM, Christoffer Dall wrote: > On Thu, Nov 13, 2014 at 05:57:44PM -0800, Mario Smarduch wrote: >> From: Paolo Bonzini <pbonzini@redhat.com> >> >> We now have a generic function that does most of the work of >> kvm_vm_ioctl_get_dirty_log, now use it. >> >> Signed-off-by: Mario Smarduch <m.smarduch@samsung.com> >> --- >> arch/x86/include/asm/kvm_host.h | 3 -- >> arch/x86/kvm/Kconfig | 1 + >> arch/x86/kvm/mmu.c | 4 +-- >> arch/x86/kvm/x86.c | 64 ++++++--------------------------------- >> 4 files changed, 12 insertions(+), 60 deletions(-) >> >> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h >> index 7c492ed..934dc24 100644 >> --- a/arch/x86/include/asm/kvm_host.h >> +++ b/arch/x86/include/asm/kvm_host.h >> @@ -805,9 +805,6 @@ void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask, >> >> void kvm_mmu_reset_context(struct kvm_vcpu *vcpu); >> void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot); >> -void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, >> - struct kvm_memory_slot *slot, >> - gfn_t gfn_offset, unsigned long mask); >> void kvm_mmu_zap_all(struct kvm *kvm); >> void kvm_mmu_invalidate_mmio_sptes(struct kvm *kvm); >> unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm); >> diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig >> index f9d16ff..d073594 100644 >> --- a/arch/x86/kvm/Kconfig >> +++ b/arch/x86/kvm/Kconfig >> @@ -39,6 +39,7 @@ config KVM >> select PERF_EVENTS >> select HAVE_KVM_MSI >> select HAVE_KVM_CPU_RELAX_INTERCEPT >> + select KVM_GENERIC_DIRTYLOG_READ_PROTECT >> select KVM_VFIO >> ---help--- >> Support hosting fully virtualized guest machines using hardware >> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c >> index 9314678..bf6b82c 100644 >> --- a/arch/x86/kvm/mmu.c >> +++ b/arch/x86/kvm/mmu.c >> @@ -1224,7 +1224,7 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, >> } >> >> /** >> - * kvm_mmu_write_protect_pt_masked - write protect selected PT level pages >> + * kvm_arch_mmu_write_protect_pt_masked - write protect selected PT level pages >> * @kvm: kvm instance >> * @slot: slot to protect >> * @gfn_offset: start of the BITS_PER_LONG pages we care about >> @@ -1233,7 +1233,7 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, >> * Used when we do not need to care about huge page mappings: e.g. during dirty >> * logging we do not have any such mappings. >> */ >> -void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, >> +void kvm_arch_mmu_write_protect_pt_masked(struct kvm *kvm, >> struct kvm_memory_slot *slot, >> gfn_t gfn_offset, unsigned long mask) >> { >> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c >> index 8f1e22d..9f8ae9a 100644 >> --- a/arch/x86/kvm/x86.c >> +++ b/arch/x86/kvm/x86.c >> @@ -3606,77 +3606,31 @@ static int kvm_vm_ioctl_reinject(struct kvm *kvm, >> * >> * 1. Take a snapshot of the bit and clear it if needed. >> * 2. Write protect the corresponding page. >> - * 3. Flush TLB's if needed. >> - * 4. Copy the snapshot to the userspace. >> + * 3. Copy the snapshot to the userspace. >> + * 4. Flush TLB's if needed. >> * >> - * Between 2 and 3, the guest may write to the page using the remaining TLB >> - * entry. This is not a problem because the page will be reported dirty at >> - * step 4 using the snapshot taken before and step 3 ensures that successive >> - * writes will be logged for the next call. >> + * Between 2 and 4, the guest may write to the page using the remaining TLB >> + * entry. This is not a problem because the page is reported dirty using >> + * the snapshot taken before and step 4 ensures that writes done after >> + * exiting to userspace will be logged for the next call. >> */ > > this seems to duplicate the comment in virt/kvm/kvm_main.c, but > whatever. > > FWIW: > Acked-by: Christoffer Dall <christoffer.dall@linaro.org> > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 09/12/2014 00:12, Mario Smarduch wrote: > Hi Paolo, > I took a closer look at Christoffers comment, > the _log description in x86.c is a repeat of the > _protect description in kvm_main.c. > > I'm wondering if description below would be acceptable, or > perhaps you had a reason leaving it as is. Yes, it's okay. > For the ARM variant I would word same. Please advise. > > Thanks. > > " > /** > * kvm_vm_ioctl_get_dirty_log - get and clear the log of dirty pages in > a slot > * @kvm: kvm instance > * @log: slot id and address to which we copy the log > * > * Steps 1-4 below provide general overview of dirty page logging. See > * kvm_get_dirty_log_protect() function description for additional details. > * > * We call kvm_get_dirty_log_protect() to handle steps 1-3, upon return we > * always flush the TLB (step 4) even if 'protect' failed and dirty bitmap even if a previous step failed and the dirty bitmap may be corrupt. > * may be corrupt. Regardless of previous outcome KVM logging API does not ... the KVM logging API ... > * preclude user space subsequent dirty log read. Flushing TLB insures s/insures/ensures/ Paolo > writes > * will be marked dirty for next log read. > * > * 1. Take a snapshot of the bit and clear it if needed. > * 2. Write protect the corresponding page. > * 3. Copy the snapshot to the userspace. > * 4. Flush TLB's if needed. > */ > " > > On 11/22/2014 11:19 AM, Christoffer Dall wrote: >> On Thu, Nov 13, 2014 at 05:57:44PM -0800, Mario Smarduch wrote: >>> From: Paolo Bonzini <pbonzini@redhat.com> >>> >>> We now have a generic function that does most of the work of >>> kvm_vm_ioctl_get_dirty_log, now use it. >>> >>> Signed-off-by: Mario Smarduch <m.smarduch@samsung.com> >>> --- >>> arch/x86/include/asm/kvm_host.h | 3 -- >>> arch/x86/kvm/Kconfig | 1 + >>> arch/x86/kvm/mmu.c | 4 +-- >>> arch/x86/kvm/x86.c | 64 ++++++--------------------------------- >>> 4 files changed, 12 insertions(+), 60 deletions(-) >>> >>> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h >>> index 7c492ed..934dc24 100644 >>> --- a/arch/x86/include/asm/kvm_host.h >>> +++ b/arch/x86/include/asm/kvm_host.h >>> @@ -805,9 +805,6 @@ void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask, >>> >>> void kvm_mmu_reset_context(struct kvm_vcpu *vcpu); >>> void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot); >>> -void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, >>> - struct kvm_memory_slot *slot, >>> - gfn_t gfn_offset, unsigned long mask); >>> void kvm_mmu_zap_all(struct kvm *kvm); >>> void kvm_mmu_invalidate_mmio_sptes(struct kvm *kvm); >>> unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm); >>> diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig >>> index f9d16ff..d073594 100644 >>> --- a/arch/x86/kvm/Kconfig >>> +++ b/arch/x86/kvm/Kconfig >>> @@ -39,6 +39,7 @@ config KVM >>> select PERF_EVENTS >>> select HAVE_KVM_MSI >>> select HAVE_KVM_CPU_RELAX_INTERCEPT >>> + select KVM_GENERIC_DIRTYLOG_READ_PROTECT >>> select KVM_VFIO >>> ---help--- >>> Support hosting fully virtualized guest machines using hardware >>> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c >>> index 9314678..bf6b82c 100644 >>> --- a/arch/x86/kvm/mmu.c >>> +++ b/arch/x86/kvm/mmu.c >>> @@ -1224,7 +1224,7 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, >>> } >>> >>> /** >>> - * kvm_mmu_write_protect_pt_masked - write protect selected PT level pages >>> + * kvm_arch_mmu_write_protect_pt_masked - write protect selected PT level pages >>> * @kvm: kvm instance >>> * @slot: slot to protect >>> * @gfn_offset: start of the BITS_PER_LONG pages we care about >>> @@ -1233,7 +1233,7 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, >>> * Used when we do not need to care about huge page mappings: e.g. during dirty >>> * logging we do not have any such mappings. >>> */ >>> -void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, >>> +void kvm_arch_mmu_write_protect_pt_masked(struct kvm *kvm, >>> struct kvm_memory_slot *slot, >>> gfn_t gfn_offset, unsigned long mask) >>> { >>> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c >>> index 8f1e22d..9f8ae9a 100644 >>> --- a/arch/x86/kvm/x86.c >>> +++ b/arch/x86/kvm/x86.c >>> @@ -3606,77 +3606,31 @@ static int kvm_vm_ioctl_reinject(struct kvm *kvm, >>> * >>> * 1. Take a snapshot of the bit and clear it if needed. >>> * 2. Write protect the corresponding page. >>> - * 3. Flush TLB's if needed. >>> - * 4. Copy the snapshot to the userspace. >>> + * 3. Copy the snapshot to the userspace. >>> + * 4. Flush TLB's if needed. >>> * >>> - * Between 2 and 3, the guest may write to the page using the remaining TLB >>> - * entry. This is not a problem because the page will be reported dirty at >>> - * step 4 using the snapshot taken before and step 3 ensures that successive >>> - * writes will be logged for the next call. >>> + * Between 2 and 4, the guest may write to the page using the remaining TLB >>> + * entry. This is not a problem because the page is reported dirty using >>> + * the snapshot taken before and step 4 ensures that writes done after >>> + * exiting to userspace will be logged for the next call. >>> */ >> >> this seems to duplicate the comment in virt/kvm/kvm_main.c, but >> whatever. >> >> FWIW: >> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> >> > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 7c492ed..934dc24 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -805,9 +805,6 @@ void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask, void kvm_mmu_reset_context(struct kvm_vcpu *vcpu); void kvm_mmu_slot_remove_write_access(struct kvm *kvm, int slot); -void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, - struct kvm_memory_slot *slot, - gfn_t gfn_offset, unsigned long mask); void kvm_mmu_zap_all(struct kvm *kvm); void kvm_mmu_invalidate_mmio_sptes(struct kvm *kvm); unsigned int kvm_mmu_calculate_mmu_pages(struct kvm *kvm); diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig index f9d16ff..d073594 100644 --- a/arch/x86/kvm/Kconfig +++ b/arch/x86/kvm/Kconfig @@ -39,6 +39,7 @@ config KVM select PERF_EVENTS select HAVE_KVM_MSI select HAVE_KVM_CPU_RELAX_INTERCEPT + select KVM_GENERIC_DIRTYLOG_READ_PROTECT select KVM_VFIO ---help--- Support hosting fully virtualized guest machines using hardware diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 9314678..bf6b82c 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1224,7 +1224,7 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, } /** - * kvm_mmu_write_protect_pt_masked - write protect selected PT level pages + * kvm_arch_mmu_write_protect_pt_masked - write protect selected PT level pages * @kvm: kvm instance * @slot: slot to protect * @gfn_offset: start of the BITS_PER_LONG pages we care about @@ -1233,7 +1233,7 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, * Used when we do not need to care about huge page mappings: e.g. during dirty * logging we do not have any such mappings. */ -void kvm_mmu_write_protect_pt_masked(struct kvm *kvm, +void kvm_arch_mmu_write_protect_pt_masked(struct kvm *kvm, struct kvm_memory_slot *slot, gfn_t gfn_offset, unsigned long mask) { diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 8f1e22d..9f8ae9a 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3606,77 +3606,31 @@ static int kvm_vm_ioctl_reinject(struct kvm *kvm, * * 1. Take a snapshot of the bit and clear it if needed. * 2. Write protect the corresponding page. - * 3. Flush TLB's if needed. - * 4. Copy the snapshot to the userspace. + * 3. Copy the snapshot to the userspace. + * 4. Flush TLB's if needed. * - * Between 2 and 3, the guest may write to the page using the remaining TLB - * entry. This is not a problem because the page will be reported dirty at - * step 4 using the snapshot taken before and step 3 ensures that successive - * writes will be logged for the next call. + * Between 2 and 4, the guest may write to the page using the remaining TLB + * entry. This is not a problem because the page is reported dirty using + * the snapshot taken before and step 4 ensures that writes done after + * exiting to userspace will be logged for the next call. */ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log) { - int r; - struct kvm_memory_slot *memslot; - unsigned long n, i; - unsigned long *dirty_bitmap; - unsigned long *dirty_bitmap_buffer; bool is_dirty = false; + int r; mutex_lock(&kvm->slots_lock); - r = -EINVAL; - if (log->slot >= KVM_USER_MEM_SLOTS) - goto out; - - memslot = id_to_memslot(kvm->memslots, log->slot); - - dirty_bitmap = memslot->dirty_bitmap; - r = -ENOENT; - if (!dirty_bitmap) - goto out; - - n = kvm_dirty_bitmap_bytes(memslot); - - dirty_bitmap_buffer = dirty_bitmap + n / sizeof(long); - memset(dirty_bitmap_buffer, 0, n); - - spin_lock(&kvm->mmu_lock); - - for (i = 0; i < n / sizeof(long); i++) { - unsigned long mask; - gfn_t offset; - - if (!dirty_bitmap[i]) - continue; - - is_dirty = true; - - mask = xchg(&dirty_bitmap[i], 0); - dirty_bitmap_buffer[i] = mask; - - offset = i * BITS_PER_LONG; - kvm_mmu_write_protect_pt_masked(kvm, memslot, offset, mask); - } - - spin_unlock(&kvm->mmu_lock); - - /* See the comments in kvm_mmu_slot_remove_write_access(). */ - lockdep_assert_held(&kvm->slots_lock); + r = kvm_get_dirty_log_protect(kvm, log, &is_dirty); /* * All the TLBs can be flushed out of mmu lock, see the comments in * kvm_mmu_slot_remove_write_access(). */ + lockdep_assert_held(&kvm->slots_lock); if (is_dirty) kvm_flush_remote_tlbs(kvm); - r = -EFAULT; - if (copy_to_user(log->dirty_bitmap, dirty_bitmap_buffer, n)) - goto out; - - r = 0; -out: mutex_unlock(&kvm->slots_lock); return r; }