4.19-stable review patch. If anyone has any objections, please let me know.
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From: Janis Schoetterl-Glausch scgl@linux.ibm.com
[ Upstream commit 416e7f0c9d613bf84e182eba9547ae8f9f5bfa4c ]
Improve readability by renaming the length variable and not calculating the offset manually.
Signed-off-by: Janis Schoetterl-Glausch scgl@linux.ibm.com Reviewed-by: Janosch Frank frankja@linux.ibm.com Reviewed-by: David Hildenbrand david@redhat.com Reviewed-by: Claudio Imbrenda imbrenda@linux.ibm.com Message-Id: 20211126164549.7046-2-scgl@linux.ibm.com Signed-off-by: Janosch Frank frankja@linux.ibm.com Stable-dep-of: e8061f06185b ("KVM: s390: gaccess: Check if guest address is in memslot") Signed-off-by: Sasha Levin sashal@kernel.org --- 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 07d30ffcfa412..b184749ffc5ae 100644 --- a/arch/s390/kvm/gaccess.c +++ b/arch/s390/kvm/gaccess.c @@ -831,8 +831,9 @@ 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 long pages_array[2]; + unsigned int fragment_len; unsigned long *pages; int need_ipte_lock; union asce asce; @@ -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; }