diff mbox series

[RFC,02/15] KVM: Add kvm/vcpu argument to mark_dirty_page_in_slot

Message ID 20191129213505.18472-3-peterx@redhat.com (mailing list archive)
State New, archived
Headers show
Series KVM: Dirty ring interface | expand

Commit Message

Peter Xu Nov. 29, 2019, 9:34 p.m. UTC 
From: "Cao, Lei" <Lei.Cao@stratus.com>

Signed-off-by: Cao, Lei <Lei.Cao@stratus.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
---
 virt/kvm/kvm_main.c | 26 +++++++++++++++++---------
 1 file changed, 17 insertions(+), 9 deletions(-)

Comments

Sean Christopherson Dec. 2, 2019, 7:32 p.m. UTC | #1 
On Fri, Nov 29, 2019 at 04:34:52PM -0500, Peter Xu wrote:

Why?

> From: "Cao, Lei" <Lei.Cao@stratus.com>
> 
> Signed-off-by: Cao, Lei <Lei.Cao@stratus.com>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>  virt/kvm/kvm_main.c | 26 +++++++++++++++++---------
>  1 file changed, 17 insertions(+), 9 deletions(-)
> 
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index fac0760c870e..8f8940cc4b84 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -145,7 +145,10 @@ static void hardware_disable_all(void);
>  
>  static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
>  
> -static void mark_page_dirty_in_slot(struct kvm_memory_slot *memslot, gfn_t gfn);
> +static void mark_page_dirty_in_slot(struct kvm *kvm,
> +				    struct kvm_vcpu *vcpu,
> +				    struct kvm_memory_slot *memslot,
> +				    gfn_t gfn);

Why both?  Passing @vcpu gets you @kvm.
Peter Xu Dec. 2, 2019, 8:49 p.m. UTC | #2 
On Mon, Dec 02, 2019 at 11:32:22AM -0800, Sean Christopherson wrote:
> On Fri, Nov 29, 2019 at 04:34:52PM -0500, Peter Xu wrote:
> 
> Why?

[1]

> 
> > From: "Cao, Lei" <Lei.Cao@stratus.com>
> > 
> > Signed-off-by: Cao, Lei <Lei.Cao@stratus.com>
> > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> > Signed-off-by: Peter Xu <peterx@redhat.com>
> > ---
> >  virt/kvm/kvm_main.c | 26 +++++++++++++++++---------
> >  1 file changed, 17 insertions(+), 9 deletions(-)
> > 
> > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> > index fac0760c870e..8f8940cc4b84 100644
> > --- a/virt/kvm/kvm_main.c
> > +++ b/virt/kvm/kvm_main.c
> > @@ -145,7 +145,10 @@ static void hardware_disable_all(void);
> >  
> >  static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
> >  
> > -static void mark_page_dirty_in_slot(struct kvm_memory_slot *memslot, gfn_t gfn);
> > +static void mark_page_dirty_in_slot(struct kvm *kvm,
> > +				    struct kvm_vcpu *vcpu,
> > +				    struct kvm_memory_slot *memslot,
> > +				    gfn_t gfn);
> 
> Why both?  Passing @vcpu gets you @kvm.

You are right on that I should fill in something at [1]..

Because @vcpu can be NULL (if you continue to read this patch, you'll
see sometimes NULL is passed in), and we at least need a context to
mark the dirty ring.  That's also why we need a per-vm dirty ring to
be the fallback of the cases where we don't have vcpu context.

Thanks,
diff mbox series

Patch

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index fac0760c870e..8f8940cc4b84 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -145,7 +145,10 @@  static void hardware_disable_all(void);
 
 static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
 
-static void mark_page_dirty_in_slot(struct kvm_memory_slot *memslot, gfn_t gfn);
+static void mark_page_dirty_in_slot(struct kvm *kvm,
+				    struct kvm_vcpu *vcpu,
+				    struct kvm_memory_slot *memslot,
+				    gfn_t gfn);
 
 __visible bool kvm_rebooting;
 EXPORT_SYMBOL_GPL(kvm_rebooting);
@@ -2077,7 +2080,8 @@  int kvm_vcpu_read_guest_atomic(struct kvm_vcpu *vcpu, gpa_t gpa,
 }
 EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_atomic);
 
-static int __kvm_write_guest_page(struct kvm_memory_slot *memslot, gfn_t gfn,
+static int __kvm_write_guest_page(struct kvm *kvm, struct kvm_vcpu *vcpu,
+				  struct kvm_memory_slot *memslot, gfn_t gfn,
 			          const void *data, int offset, int len)
 {
 	int r;
@@ -2089,7 +2093,7 @@  static int __kvm_write_guest_page(struct kvm_memory_slot *memslot, gfn_t gfn,
 	r = __copy_to_user((void __user *)addr + offset, data, len);
 	if (r)
 		return -EFAULT;
-	mark_page_dirty_in_slot(memslot, gfn);
+	mark_page_dirty_in_slot(kvm, vcpu, memslot, gfn);
 	return 0;
 }
 
@@ -2098,7 +2102,8 @@  int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn,
 {
 	struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
 
-	return __kvm_write_guest_page(slot, gfn, data, offset, len);
+	return __kvm_write_guest_page(kvm, NULL, slot, gfn, data,
+				      offset, len);
 }
 EXPORT_SYMBOL_GPL(kvm_write_guest_page);
 
@@ -2107,7 +2112,8 @@  int kvm_vcpu_write_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn,
 {
 	struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
 
-	return __kvm_write_guest_page(slot, gfn, data, offset, len);
+	return __kvm_write_guest_page(vcpu->kvm, vcpu, slot, gfn, data,
+				      offset, len);
 }
 EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest_page);
 
@@ -2221,7 +2227,7 @@  int kvm_write_guest_offset_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
 	r = __copy_to_user((void __user *)ghc->hva + offset, data, len);
 	if (r)
 		return -EFAULT;
-	mark_page_dirty_in_slot(ghc->memslot, gpa >> PAGE_SHIFT);
+	mark_page_dirty_in_slot(kvm, NULL, ghc->memslot, gpa >> PAGE_SHIFT);
 
 	return 0;
 }
@@ -2286,7 +2292,9 @@  int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
 }
 EXPORT_SYMBOL_GPL(kvm_clear_guest);
 
-static void mark_page_dirty_in_slot(struct kvm_memory_slot *memslot,
+static void mark_page_dirty_in_slot(struct kvm *kvm,
+				    struct kvm_vcpu *vcpu,
+				    struct kvm_memory_slot *memslot,
 				    gfn_t gfn)
 {
 	if (memslot && memslot->dirty_bitmap) {
@@ -2301,7 +2309,7 @@  void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
 	struct kvm_memory_slot *memslot;
 
 	memslot = gfn_to_memslot(kvm, gfn);
-	mark_page_dirty_in_slot(memslot, gfn);
+	mark_page_dirty_in_slot(kvm, NULL, memslot, gfn);
 }
 EXPORT_SYMBOL_GPL(mark_page_dirty);
 
@@ -2310,7 +2318,7 @@  void kvm_vcpu_mark_page_dirty(struct kvm_vcpu *vcpu, gfn_t gfn)
 	struct kvm_memory_slot *memslot;
 
 	memslot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
-	mark_page_dirty_in_slot(memslot, gfn);
+	mark_page_dirty_in_slot(vcpu->kvm, vcpu, memslot, gfn);
 }
 EXPORT_SYMBOL_GPL(kvm_vcpu_mark_page_dirty);