[PATCH] KVM: Move gfn_to_memslot() to kvm_host.h

This moves gfn_to_memslot(), and the functions it calls, that is,
search_memslots() and __gfn_to_memslot(), from kvm_main.c to kvm_host.h
so that gfn_to_memslot() can be called from non-modular code even
when KVM is a module.  On powerpc, the Book3S HV style of KVM has
code that is called from real mode which needs to call gfn_to_memslot()
and thus needs this.  (Module code is allocated in the vmalloc region,
which can't be accessed in real mode.)

With this, we can remove builtin_gfn_to_memslot() from book3s_hv_rm_mmu.c
and thus eliminate a little bit of duplication.

Signed-off-by: Paul Mackerras <redacted>
---
 arch/powerpc/kvm/book3s_hv_rm_mmu.c |   23 ++---------------------
 include/linux/kvm_host.h            |   25 ++++++++++++++++++++++++-
 virt/kvm/kvm_main.c                 |   25 -------------------------
 3 files changed, 26 insertions(+), 47 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
index d3e36fc..063b00c 100644
--- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c
+++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c

@@ -21,25 +21,6 @@
 #include <asm/synch.h>
 #include <asm/ppc-opcode.h>
 
-/*
- * Since this file is built in even if KVM is a module, we need
- * a local copy of this function for the case where kvm_main.c is
- * modular.
- */
-static struct kvm_memory_slot *builtin_gfn_to_memslot(struct kvm *kvm,
-						gfn_t gfn)
-{
-	struct kvm_memslots *slots;
-	struct kvm_memory_slot *memslot;
-
-	slots = kvm_memslots(kvm);
-	kvm_for_each_memslot(memslot, slots)
-		if (gfn >= memslot->base_gfn &&
-		      gfn < memslot->base_gfn + memslot->npages)
-			return memslot;
-	return NULL;
-}
-
 /* Translate address of a vmalloc'd thing to a linear map address */
 static void *real_vmalloc_addr(void *x)
 {

@@ -97,7 +78,7 @@ static void remove_revmap_chain(struct kvm *kvm, long pte_index,
 	rev = real_vmalloc_addr(&kvm->arch.revmap[pte_index]);
 	ptel = rev->guest_rpte;
 	gfn = hpte_rpn(ptel, hpte_page_size(hpte_v, ptel));
-	memslot = builtin_gfn_to_memslot(kvm, gfn);
+	memslot = gfn_to_memslot(kvm, gfn);
 	if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID))
 		return;
 

@@ -171,7 +152,7 @@ long kvmppc_h_enter(struct kvm_vcpu *vcpu, unsigned long flags,
 	/* Find the memslot (if any) for this address */
 	gpa = (ptel & HPTE_R_RPN) & ~(psize - 1);
 	gfn = gpa >> PAGE_SHIFT;
-	memslot = builtin_gfn_to_memslot(kvm, gfn);
+	memslot = gfn_to_memslot(kvm, gfn);
 	pa = 0;
 	is_io = ~0ul;
 	rmap = NULL;

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index ec79a45..109828f 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h

@@ -429,7 +429,6 @@ int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
 			      gpa_t gpa);
 int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len);
 int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len);
-struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn);
 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn);
 unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn);
 void mark_page_dirty(struct kvm *kvm, gfn_t gfn);

@@ -649,6 +648,30 @@ static inline void kvm_guest_exit(void)
 	current->flags &= ~PF_VCPU;
 }
 
+static inline struct kvm_memory_slot *
+search_memslots(struct kvm_memslots *slots, gfn_t gfn)
+{
+	struct kvm_memory_slot *memslot;
+
+	kvm_for_each_memslot(memslot, slots)
+		if (gfn >= memslot->base_gfn &&
+		      gfn < memslot->base_gfn + memslot->npages)
+			return memslot;
+
+	return NULL;
+}
+
+static inline struct kvm_memory_slot *
+__gfn_to_memslot(struct kvm_memslots *slots, gfn_t gfn)
+{
+	return search_memslots(slots, gfn);
+}
+
+static inline struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
+{
+	return __gfn_to_memslot(kvm_memslots(kvm), gfn);
+}
+
 static inline int memslot_id(struct kvm *kvm, gfn_t gfn)
 {
 	return gfn_to_memslot(kvm, gfn)->id;

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index c144132..ef11529 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c

@@ -640,19 +640,6 @@ static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
 }
 #endif /* !CONFIG_S390 */
 
-static struct kvm_memory_slot *
-search_memslots(struct kvm_memslots *slots, gfn_t gfn)
-{
-	struct kvm_memory_slot *memslot;
-
-	kvm_for_each_memslot(memslot, slots)
-		if (gfn >= memslot->base_gfn &&
-		      gfn < memslot->base_gfn + memslot->npages)
-			return memslot;
-
-	return NULL;
-}
-
 static int cmp_memslot(const void *slot1, const void *slot2)
 {
 	struct kvm_memory_slot *s1, *s2;

@@ -1031,18 +1018,6 @@ int kvm_is_error_hva(unsigned long addr)
 }
 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
 
-static struct kvm_memory_slot *__gfn_to_memslot(struct kvm_memslots *slots,
-						gfn_t gfn)
-{
-	return search_memslots(slots, gfn);
-}
-
-struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
-{
-	return __gfn_to_memslot(kvm_memslots(kvm), gfn);
-}
-EXPORT_SYMBOL_GPL(gfn_to_memslot);
-
 int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
 {
 	struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);

-- 
1.7.5.4

On 20.12.2011, at 10:21, Paul Mackerras wrote:

This moves gfn_to_memslot(), and the functions it calls, that is,
search_memslots() and __gfn_to_memslot(), from kvm_main.c to kvm_host.h
so that gfn_to_memslot() can be called from non-modular code even
when KVM is a module.  On powerpc, the Book3S HV style of KVM has
code that is called from real mode which needs to call gfn_to_memslot()
and thus needs this.  (Module code is allocated in the vmalloc region,
which can't be accessed in real mode.)

With this, we can remove builtin_gfn_to_memslot() from book3s_hv_rm_mmu.c
and thus eliminate a little bit of duplication.

Signed-off-by: Paul Mackerras <redacted>

Avi, please ack.


Alex

On 12/20/2011 11:21 AM, Paul Mackerras wrote:

This moves gfn_to_memslot(), and the functions it calls, that is,
search_memslots() and __gfn_to_memslot(), from kvm_main.c to kvm_host.h
so that gfn_to_memslot() can be called from non-modular code even
when KVM is a module.  On powerpc, the Book3S HV style of KVM has
code that is called from real mode which needs to call gfn_to_memslot()
and thus needs this.  (Module code is allocated in the vmalloc region,
which can't be accessed in real mode.)

With this, we can remove builtin_gfn_to_memslot() from book3s_hv_rm_mmu.c
and thus eliminate a little bit of duplication.

Those functions are too big to be inlined IMO.  How about moving them to
another C file, and making it builtin for ppc?

The only issue is what to call it. virt/kvm/builtin-for-ppc seems silly.

Or we could move the implementation into a header file, with an extra __
prefix, and have the C stubs call those inlines, so we have exactly on
instantiation.  Your real mode code can then call the inlines.

-- 
error compiling committee.c: too many arguments to function

On 26.12.2011, at 14:22, Avi Kivity wrote:

On 12/20/2011 11:21 AM, Paul Mackerras wrote:

quoted

This moves gfn_to_memslot(), and the functions it calls, that is,
search_memslots() and __gfn_to_memslot(), from kvm_main.c to kvm_host.h
so that gfn_to_memslot() can be called from non-modular code even
when KVM is a module.  On powerpc, the Book3S HV style of KVM has
code that is called from real mode which needs to call gfn_to_memslot()
and thus needs this.  (Module code is allocated in the vmalloc region,
which can't be accessed in real mode.)

With this, we can remove builtin_gfn_to_memslot() from book3s_hv_rm_mmu.c
and thus eliminate a little bit of duplication.

Those functions are too big to be inlined IMO.  How about moving them to
another C file, and making it builtin for ppc?

The only issue is what to call it. virt/kvm/builtin-for-ppc seems silly.

Yeah - and it makes it pretty confusing to find the functions then.

Or we could move the implementation into a header file, with an extra __
prefix, and have the C stubs call those inlines, so we have exactly on
instantiation.  Your real mode code can then call the inlines.

I like this version. That way everyone should be happy :)


Alex

On 01/02/2012 05:23 PM, Alexander Graf wrote:

quoted

Or we could move the implementation into a header file, with an extra __
prefix, and have the C stubs call those inlines, so we have exactly on
instantiation.  Your real mode code can then call the inlines.

I like this version. That way everyone should be happy :)

Pretty much how everything is solved.  Pile up another layer of
indirection (compile-time here), everyone's happy, and the code bloats.

(I'm not against this, just grumpy)

-- 
error compiling committee.c: too many arguments to function

This moves __gfn_to_memslot() and search_memslots() from kvm_main.c to
kvm_host.h to reduce the code duplication caused by the need for
non-modular code in arch/powerpc/kvm/book3s_hv_rm_mmu.c to call
gfn_to_memslot() in real mode.

Rather than putting gfn_to_memslot() itself in a header, which would
lead to increased code size, this puts __gfn_to_memslot() in a header.
Then, the non-modular uses of gfn_to_memslot() are changed to call
__gfn_to_memslot() instead.  This way there is only one place in the
source code that needs to be changed should the gfn_to_memslot()
implementation need to be modified.

On powerpc, the Book3S HV style of KVM has code that is called from
real mode which needs to call gfn_to_memslot() and thus needs this.
(Module code is allocated in the vmalloc region, which can't be
accessed in real mode.)

With this, we can remove builtin_gfn_to_memslot() from book3s_hv_rm_mmu.c.

Signed-off-by: Paul Mackerras <redacted>
---
 arch/powerpc/kvm/book3s_hv_rm_mmu.c |   23 ++---------------------
 include/linux/kvm_host.h            |   19 +++++++++++++++++++
 virt/kvm/kvm_main.c                 |   19 -------------------
 3 files changed, 21 insertions(+), 40 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
index d3e36fc..9055cd2 100644
--- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c
+++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c

@@ -21,25 +21,6 @@
 #include <asm/synch.h>
 #include <asm/ppc-opcode.h>
 
-/*
- * Since this file is built in even if KVM is a module, we need
- * a local copy of this function for the case where kvm_main.c is
- * modular.
- */
-static struct kvm_memory_slot *builtin_gfn_to_memslot(struct kvm *kvm,
-						gfn_t gfn)
-{
-	struct kvm_memslots *slots;
-	struct kvm_memory_slot *memslot;
-
-	slots = kvm_memslots(kvm);
-	kvm_for_each_memslot(memslot, slots)
-		if (gfn >= memslot->base_gfn &&
-		      gfn < memslot->base_gfn + memslot->npages)
-			return memslot;
-	return NULL;
-}
-
 /* Translate address of a vmalloc'd thing to a linear map address */
 static void *real_vmalloc_addr(void *x)
 {

@@ -97,7 +78,7 @@ static void remove_revmap_chain(struct kvm *kvm, long pte_index,
 	rev = real_vmalloc_addr(&kvm->arch.revmap[pte_index]);
 	ptel = rev->guest_rpte;
 	gfn = hpte_rpn(ptel, hpte_page_size(hpte_v, ptel));
-	memslot = builtin_gfn_to_memslot(kvm, gfn);
+	memslot = __gfn_to_memslot(kvm_memslots(kvm), gfn);
 	if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID))
 		return;
 

@@ -171,7 +152,7 @@ long kvmppc_h_enter(struct kvm_vcpu *vcpu, unsigned long flags,
 	/* Find the memslot (if any) for this address */
 	gpa = (ptel & HPTE_R_RPN) & ~(psize - 1);
 	gfn = gpa >> PAGE_SHIFT;
-	memslot = builtin_gfn_to_memslot(kvm, gfn);
+	memslot = __gfn_to_memslot(kvm_memslots(kvm), gfn);
 	pa = 0;
 	is_io = ~0ul;
 	rmap = NULL;

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index ec79a45..86d08f0 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h

@@ -649,6 +649,25 @@ static inline void kvm_guest_exit(void)
 	current->flags &= ~PF_VCPU;
 }
 
+static inline struct kvm_memory_slot *
+search_memslots(struct kvm_memslots *slots, gfn_t gfn)
+{
+	struct kvm_memory_slot *memslot;
+
+	kvm_for_each_memslot(memslot, slots)
+		if (gfn >= memslot->base_gfn &&
+		      gfn < memslot->base_gfn + memslot->npages)
+			return memslot;
+
+	return NULL;
+}
+
+static inline struct kvm_memory_slot *
+__gfn_to_memslot(struct kvm_memslots *slots, gfn_t gfn)
+{
+	return search_memslots(slots, gfn);
+}
+
 static inline int memslot_id(struct kvm *kvm, gfn_t gfn)
 {
 	return gfn_to_memslot(kvm, gfn)->id;

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index c144132..5de8f61 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c

@@ -640,19 +640,6 @@ static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
 }
 #endif /* !CONFIG_S390 */
 
-static struct kvm_memory_slot *
-search_memslots(struct kvm_memslots *slots, gfn_t gfn)
-{
-	struct kvm_memory_slot *memslot;
-
-	kvm_for_each_memslot(memslot, slots)
-		if (gfn >= memslot->base_gfn &&
-		      gfn < memslot->base_gfn + memslot->npages)
-			return memslot;
-
-	return NULL;
-}
-
 static int cmp_memslot(const void *slot1, const void *slot2)
 {
 	struct kvm_memory_slot *s1, *s2;

@@ -1031,12 +1018,6 @@ int kvm_is_error_hva(unsigned long addr)
 }
 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
 
-static struct kvm_memory_slot *__gfn_to_memslot(struct kvm_memslots *slots,
-						gfn_t gfn)
-{
-	return search_memslots(slots, gfn);
-}
-
 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
 {
 	return __gfn_to_memslot(kvm_memslots(kvm), gfn);

-- 
1.7.8.3

On 01/12/2012 11:41 AM, Paul Mackerras wrote:

This moves __gfn_to_memslot() and search_memslots() from kvm_main.c to
kvm_host.h to reduce the code duplication caused by the need for
non-modular code in arch/powerpc/kvm/book3s_hv_rm_mmu.c to call
gfn_to_memslot() in real mode.

Rather than putting gfn_to_memslot() itself in a header, which would
lead to increased code size, this puts __gfn_to_memslot() in a header.
Then, the non-modular uses of gfn_to_memslot() are changed to call
__gfn_to_memslot() instead.  This way there is only one place in the
source code that needs to be changed should the gfn_to_memslot()
implementation need to be modified.

On powerpc, the Book3S HV style of KVM has code that is called from
real mode which needs to call gfn_to_memslot() and thus needs this.
(Module code is allocated in the vmalloc region, which can't be
accessed in real mode.)

With this, we can remove builtin_gfn_to_memslot() from book3s_hv_rm_mmu.c.

Signed-off-by: Paul Mackerras<redacted>

Confusing to review, but looks correct :). Avi, please ack.


Alex

On 01/12/2012 12:41 PM, Paul Mackerras wrote:

This moves __gfn_to_memslot() and search_memslots() from kvm_main.c to
kvm_host.h to reduce the code duplication caused by the need for
non-modular code in arch/powerpc/kvm/book3s_hv_rm_mmu.c to call
gfn_to_memslot() in real mode.

Rather than putting gfn_to_memslot() itself in a header, which would
lead to increased code size, this puts __gfn_to_memslot() in a header.
Then, the non-modular uses of gfn_to_memslot() are changed to call
__gfn_to_memslot() instead.  This way there is only one place in the
source code that needs to be changed should the gfn_to_memslot()
implementation need to be modified.

On powerpc, the Book3S HV style of KVM has code that is called from
real mode which needs to call gfn_to_memslot() and thus needs this.
(Module code is allocated in the vmalloc region, which can't be
accessed in real mode.)

 
+static inline struct kvm_memory_slot *
+search_memslots(struct kvm_memslots *slots, gfn_t gfn)
+{
+	struct kvm_memory_slot *memslot;
+
+	kvm_for_each_memslot(memslot, slots)
+		if (gfn >= memslot->base_gfn &&
+		      gfn < memslot->base_gfn + memslot->npages)
+			return memslot;
+
+	return NULL;
+}
+
+static inline struct kvm_memory_slot *
+__gfn_to_memslot(struct kvm_memslots *slots, gfn_t gfn)
+{
+	return search_memslots(slots, gfn);
+}

Please add a comment here explaining why these functions are inlined. 
There's also the call to kvm_gfn_to_hva_cache_init(), which should be
changed to gfn_to_memslot(), to avoid code bloat.



-- 
error compiling committee.c: too many arguments to function

This moves __gfn_to_memslot() and search_memslots() from kvm_main.c to
kvm_host.h to reduce the code duplication caused by the need for
non-modular code in arch/powerpc/kvm/book3s_hv_rm_mmu.c to call
gfn_to_memslot() in real mode.

Rather than putting gfn_to_memslot() itself in a header, which would
lead to increased code size, this puts __gfn_to_memslot() in a header.
Then, the non-modular uses of gfn_to_memslot() are changed to call
__gfn_to_memslot() instead.  This way there is only one place in the
source code that needs to be changed should the gfn_to_memslot()
implementation need to be modified.

On powerpc, the Book3S HV style of KVM has code that is called from
real mode which needs to call gfn_to_memslot() and thus needs this.
(Module code is allocated in the vmalloc region, which can't be
accessed in real mode.)

With this, we can remove builtin_gfn_to_memslot() from book3s_hv_rm_mmu.c.

Signed-off-by: Paul Mackerras <redacted>
---
v3: Add comment, change kvm_gfn_to_hva_cache_init as requested.

 arch/powerpc/kvm/book3s_hv_rm_mmu.c |   23 ++---------------------
 include/linux/kvm_host.h            |   25 +++++++++++++++++++++++++
 virt/kvm/kvm_main.c                 |   21 +--------------------
 3 files changed, 28 insertions(+), 41 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv_rm_mmu.c b/arch/powerpc/kvm/book3s_hv_rm_mmu.c
index d3e36fc..9055cd2 100644
--- a/arch/powerpc/kvm/book3s_hv_rm_mmu.c
+++ b/arch/powerpc/kvm/book3s_hv_rm_mmu.c

@@ -21,25 +21,6 @@
 #include <asm/synch.h>
 #include <asm/ppc-opcode.h>
 
-/*
- * Since this file is built in even if KVM is a module, we need
- * a local copy of this function for the case where kvm_main.c is
- * modular.
- */
-static struct kvm_memory_slot *builtin_gfn_to_memslot(struct kvm *kvm,
-						gfn_t gfn)
-{
-	struct kvm_memslots *slots;
-	struct kvm_memory_slot *memslot;
-
-	slots = kvm_memslots(kvm);
-	kvm_for_each_memslot(memslot, slots)
-		if (gfn >= memslot->base_gfn &&
-		      gfn < memslot->base_gfn + memslot->npages)
-			return memslot;
-	return NULL;
-}
-
 /* Translate address of a vmalloc'd thing to a linear map address */
 static void *real_vmalloc_addr(void *x)
 {

@@ -97,7 +78,7 @@ static void remove_revmap_chain(struct kvm *kvm, long pte_index,
 	rev = real_vmalloc_addr(&kvm->arch.revmap[pte_index]);
 	ptel = rev->guest_rpte;
 	gfn = hpte_rpn(ptel, hpte_page_size(hpte_v, ptel));
-	memslot = builtin_gfn_to_memslot(kvm, gfn);
+	memslot = __gfn_to_memslot(kvm_memslots(kvm), gfn);
 	if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID))
 		return;
 

@@ -171,7 +152,7 @@ long kvmppc_h_enter(struct kvm_vcpu *vcpu, unsigned long flags,
 	/* Find the memslot (if any) for this address */
 	gpa = (ptel & HPTE_R_RPN) & ~(psize - 1);
 	gfn = gpa >> PAGE_SHIFT;
-	memslot = builtin_gfn_to_memslot(kvm, gfn);
+	memslot = __gfn_to_memslot(kvm_memslots(kvm), gfn);
 	pa = 0;
 	is_io = ~0ul;
 	rmap = NULL;

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index ec79a45..688f37b 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h

@@ -649,6 +649,31 @@ static inline void kvm_guest_exit(void)
 	current->flags &= ~PF_VCPU;
 }
 
+/*
+ * search_memslots() and __gfn_to_memslot() are here because they are
+ * used in non-modular code in arch/powerpc/kvm/book3s_hv_rm_mmu.c.
+ * gfn_to_memslot() itself isn't here as an inline because that would
+ * bloat other code too much.
+ */
+static inline struct kvm_memory_slot *
+search_memslots(struct kvm_memslots *slots, gfn_t gfn)
+{
+	struct kvm_memory_slot *memslot;
+
+	kvm_for_each_memslot(memslot, slots)
+		if (gfn >= memslot->base_gfn &&
+		      gfn < memslot->base_gfn + memslot->npages)
+			return memslot;
+
+	return NULL;
+}
+
+static inline struct kvm_memory_slot *
+__gfn_to_memslot(struct kvm_memslots *slots, gfn_t gfn)
+{
+	return search_memslots(slots, gfn);
+}
+
 static inline int memslot_id(struct kvm *kvm, gfn_t gfn)
 {
 	return gfn_to_memslot(kvm, gfn)->id;

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index c144132..8ae6b76 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c

@@ -640,19 +640,6 @@ static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
 }
 #endif /* !CONFIG_S390 */
 
-static struct kvm_memory_slot *
-search_memslots(struct kvm_memslots *slots, gfn_t gfn)
-{
-	struct kvm_memory_slot *memslot;
-
-	kvm_for_each_memslot(memslot, slots)
-		if (gfn >= memslot->base_gfn &&
-		      gfn < memslot->base_gfn + memslot->npages)
-			return memslot;
-
-	return NULL;
-}
-
 static int cmp_memslot(const void *slot1, const void *slot2)
 {
 	struct kvm_memory_slot *s1, *s2;

@@ -1031,12 +1018,6 @@ int kvm_is_error_hva(unsigned long addr)
 }
 EXPORT_SYMBOL_GPL(kvm_is_error_hva);
 
-static struct kvm_memory_slot *__gfn_to_memslot(struct kvm_memslots *slots,
-						gfn_t gfn)
-{
-	return search_memslots(slots, gfn);
-}
-
 struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
 {
 	return __gfn_to_memslot(kvm_memslots(kvm), gfn);

@@ -1459,7 +1440,7 @@ int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
 
 	ghc->gpa = gpa;
 	ghc->generation = slots->generation;
-	ghc->memslot = __gfn_to_memslot(slots, gfn);
+	ghc->memslot = gfn_to_memslot(kvm, gfn);
 	ghc->hva = gfn_to_hva_many(ghc->memslot, gfn, NULL);
 	if (!kvm_is_error_hva(ghc->hva))
 		ghc->hva += offset;

-- 
1.7.5.4

On 13.01.2012, at 07:09, Paul Mackerras wrote:

This moves __gfn_to_memslot() and search_memslots() from kvm_main.c to
kvm_host.h to reduce the code duplication caused by the need for
non-modular code in arch/powerpc/kvm/book3s_hv_rm_mmu.c to call
gfn_to_memslot() in real mode.

Rather than putting gfn_to_memslot() itself in a header, which would
lead to increased code size, this puts __gfn_to_memslot() in a header.
Then, the non-modular uses of gfn_to_memslot() are changed to call
__gfn_to_memslot() instead.  This way there is only one place in the
source code that needs to be changed should the gfn_to_memslot()
implementation need to be modified.

On powerpc, the Book3S HV style of KVM has code that is called from
real mode which needs to call gfn_to_memslot() and thus needs this.
(Module code is allocated in the vmalloc region, which can't be
accessed in real mode.)

With this, we can remove builtin_gfn_to_memslot() from book3s_hv_rm_mmu.c.

Signed-off-by: Paul Mackerras <redacted>

Avi?


Alex

On 01/16/2012 03:18 PM, Alexander Graf wrote:

Avi?

ACK!

-- 
error compiling committee.c: too many arguments to function

On 13.01.2012, at 07:09, Paul Mackerras wrote:

This moves __gfn_to_memslot() and search_memslots() from kvm_main.c to
kvm_host.h to reduce the code duplication caused by the need for
non-modular code in arch/powerpc/kvm/book3s_hv_rm_mmu.c to call
gfn_to_memslot() in real mode.
=20
Rather than putting gfn_to_memslot() itself in a header, which would
lead to increased code size, this puts __gfn_to_memslot() in a header.
Then, the non-modular uses of gfn_to_memslot() are changed to call
__gfn_to_memslot() instead.  This way there is only one place in the
source code that needs to be changed should the gfn_to_memslot()
implementation need to be modified.
=20
On powerpc, the Book3S HV style of KVM has code that is called from
real mode which needs to call gfn_to_memslot() and thus needs this.
(Module code is allocated in the vmalloc region, which can't be
accessed in real mode.)
=20
With this, we can remove builtin_gfn_to_memslot() from =

book3s_hv_rm_mmu.c.

Which tree is this against? I got this diff between your patch and the =
patch when applied on my tree:

-@@ -97,7 +78,7 @@ static void remove_revmap_chain(struct kvm *kvm, long =
pte_index,
- 	rev =3D real_vmalloc_addr(&kvm->arch.revmap[pte_index]);
- 	ptel =3D rev->guest_rpte;
+@@ -99,7 +80,7 @@ static void remove_revmap_chain(struct kvm *kvm, long =
pte_index,
+ 	rcbits =3D hpte_r & (HPTE_R_R | HPTE_R_C);
+ 	ptel =3D rev->guest_rpte |=3D rcbits;

Since this is completely unrelated to the actual change, I'll apply the =
patch either way. It'd just be interesting to know.


Alex

On Mon, Jan 16, 2012 at 02:30:41PM +0100, Alexander Graf wrote:

Which tree is this against? I got this diff between your patch and the patch when applied on my tree:

It's against your tree (previously) plus my first 13-patch series, but
not the second series of 5 patches, which presumably why you got the
difference.  Sounds like you got it applied OK; if not let me know and
I'll rebase against your current tree.

Paul.