Re: [PATCH v2 1/3] KVM: s390: gaccess: Refactor gpa and length calculation

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 10/28/21 15:55, Janis Schoetterl-Glausch wrote:
Improve readability be renaming the length variable and
not calculating the offset manually.

Signed-off-by: Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx>

Reviewed-by: Janosch Frank <frankja@xxxxxxxxxxxxx>

---
  arch/s390/kvm/gaccess.c | 32 +++++++++++++++++---------------
  1 file changed, 17 insertions(+), 15 deletions(-)

diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index 6af59c59cc1b..0d11cea92603 100644
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -831,7 +831,8 @@ int access_guest(struct kvm_vcpu *vcpu, unsigned long ga, u8 ar, void *data,
  		 unsigned long len, enum gacc_mode mode)
  {
  	psw_t *psw = &vcpu->arch.sie_block->gpsw;
-	unsigned long _len, nr_pages, gpa, idx;
+	unsigned long nr_pages, gpa, idx;
+	unsigned int fragment_len;
  	unsigned long pages_array[2];
  	unsigned long *pages;
  	int need_ipte_lock;
@@ -855,15 +856,15 @@ int access_guest(struct kvm_vcpu *vcpu, unsigned long ga, u8 ar, void *data,
  		ipte_lock(vcpu);
  	rc = guest_page_range(vcpu, ga, ar, pages, nr_pages, asce, mode);
  	for (idx = 0; idx < nr_pages && !rc; idx++) {
-		gpa = *(pages + idx) + (ga & ~PAGE_MASK);
-		_len = min(PAGE_SIZE - (gpa & ~PAGE_MASK), len);
+		gpa = pages[idx] + offset_in_page(ga);
+		fragment_len = min(PAGE_SIZE - offset_in_page(gpa), len);
  		if (mode == GACC_STORE)
-			rc = kvm_write_guest(vcpu->kvm, gpa, data, _len);
+			rc = kvm_write_guest(vcpu->kvm, gpa, data, fragment_len);
  		else
-			rc = kvm_read_guest(vcpu->kvm, gpa, data, _len);
-		len -= _len;
-		ga += _len;
-		data += _len;
+			rc = kvm_read_guest(vcpu->kvm, gpa, data, fragment_len);
+		len -= fragment_len;
+		ga += fragment_len;
+		data += fragment_len;
  	}
  	if (need_ipte_lock)
  		ipte_unlock(vcpu);
@@ -875,19 +876,20 @@ int access_guest(struct kvm_vcpu *vcpu, unsigned long ga, u8 ar, void *data,
  int access_guest_real(struct kvm_vcpu *vcpu, unsigned long gra,
  		      void *data, unsigned long len, enum gacc_mode mode)
  {
-	unsigned long _len, gpa;
+	unsigned int fragment_len;
+	unsigned long gpa;
  	int rc = 0;
while (len && !rc) {
  		gpa = kvm_s390_real_to_abs(vcpu, gra);
-		_len = min(PAGE_SIZE - (gpa & ~PAGE_MASK), len);
+		fragment_len = min(PAGE_SIZE - offset_in_page(gpa), len);
  		if (mode)
-			rc = write_guest_abs(vcpu, gpa, data, _len);
+			rc = write_guest_abs(vcpu, gpa, data, fragment_len);
  		else
-			rc = read_guest_abs(vcpu, gpa, data, _len);
-		len -= _len;
-		gra += _len;
-		data += _len;
+			rc = read_guest_abs(vcpu, gpa, data, fragment_len);
+		len -= fragment_len;
+		gra += fragment_len;
+		data += fragment_len;
  	}
  	return rc;
  }





[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [Kernel Development]     [Kernel Newbies]     [IDE]     [Security]     [Git]     [Netfilter]     [Bugtraq]     [Yosemite Info]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Linux ATA RAID]     [Samba]     [Linux Media]     [Device Mapper]

  Powered by Linux