| Message ID | 20230125212608.1860251-9-scgl@linux.ibm.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | KVM: s390: Extend MEM_OP ioctl by storage key checked cmpxchg | expand |
On 25/01/2023 22.26, Janis Schoetterl-Glausch wrote: > The vcpu and vm mem_op ioctl implementations share some functionality. > Move argument checking and buffer allocation into functions and call > them from both implementations. > This allows code reuse in case of additional future mem_op operations. > > Suggested-by: Janosch Frank <frankja@linux.ibm.com> > Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com> > --- > arch/s390/kvm/kvm-s390.c | 80 +++++++++++++++++++++------------------- > 1 file changed, 42 insertions(+), 38 deletions(-) > > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c > index e4890e04b210..e0dfaa195949 100644 > --- a/arch/s390/kvm/kvm-s390.c > +++ b/arch/s390/kvm/kvm-s390.c > @@ -2764,24 +2764,44 @@ static int kvm_s390_handle_pv(struct kvm *kvm, struct kvm_pv_cmd *cmd) > return r; > } > > -static bool access_key_invalid(u8 access_key) > +static int mem_op_validate_common(struct kvm_s390_mem_op *mop, u64 supported_flags) > { > - return access_key > 0xf; > + if (mop->flags & ~supported_flags || !mop->size) > + return -EINVAL; > + if (mop->size > MEM_OP_MAX_SIZE) > + return -E2BIG; > + if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { > + if (mop->key > 0xf) > + return -EINVAL; > + } else { > + mop->key = 0; > + } > + return 0; > +} > + > +static void *mem_op_alloc_buf(struct kvm_s390_mem_op *mop) > +{ > + void *buf; > + > + if (mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY) > + return NULL; > + buf = vmalloc(mop->size); > + if (!buf) > + return ERR_PTR(-ENOMEM); > + return buf; > } > > static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) > { > void __user *uaddr = (void __user *)mop->buf; > - u64 supported_flags; > void *tmpbuf = NULL; You likely can now remove the "= NULL" here, I guess? > int r, srcu_idx; > > - supported_flags = KVM_S390_MEMOP_F_SKEY_PROTECTION > - | KVM_S390_MEMOP_F_CHECK_ONLY; > - if (mop->flags & ~supported_flags || !mop->size) > - return -EINVAL; > - if (mop->size > MEM_OP_MAX_SIZE) > - return -E2BIG; > + r = mem_op_validate_common(mop, KVM_S390_MEMOP_F_SKEY_PROTECTION | > + KVM_S390_MEMOP_F_CHECK_ONLY); > + if (r) > + return r; > + > /* > * This is technically a heuristic only, if the kvm->lock is not > * taken, it is not guaranteed that the vm is/remains non-protected. > @@ -2793,17 +2813,9 @@ static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) > */ > if (kvm_s390_pv_get_handle(kvm)) > return -EINVAL; > - if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { > - if (access_key_invalid(mop->key)) > - return -EINVAL; > - } else { > - mop->key = 0; > - } > - if (!(mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY)) { > - tmpbuf = vmalloc(mop->size); > - if (!tmpbuf) > - return -ENOMEM; > - } > + tmpbuf = mem_op_alloc_buf(mop); > + if (IS_ERR(tmpbuf)) > + return PTR_ERR(tmpbuf); > > srcu_idx = srcu_read_lock(&kvm->srcu); > > @@ -5250,28 +5262,20 @@ static long kvm_s390_vcpu_mem_op(struct kvm_vcpu *vcpu, > { > void __user *uaddr = (void __user *)mop->buf; > void *tmpbuf = NULL; ... and here, too. But I have to admit that I'm also not sure whether I like the mem_op_alloc_buf() part or not (the mem_op_validate_common() part looks fine to me) : mem_op_alloc_buf() is a new function with 11 lines of code, and the old spots that allocate memory were only 5 lines of code each, so you now increased the LoC count and additionally have to fiddly with IS_ERR and PTR_ERR which is always a little bit ugly in my eyes ... IMHO I'd rather keep the old code here. But that's just my 0.02 €, if you think it's nicer with mem_op_alloc_buf(), I won't insist on keeping the old code. Thomas > - int r = 0; > - const u64 supported_flags = KVM_S390_MEMOP_F_INJECT_EXCEPTION > - | KVM_S390_MEMOP_F_CHECK_ONLY > - | KVM_S390_MEMOP_F_SKEY_PROTECTION; > + int r; > > - if (mop->flags & ~supported_flags || mop->ar >= NUM_ACRS || !mop->size) > + r = mem_op_validate_common(mop, KVM_S390_MEMOP_F_INJECT_EXCEPTION | > + KVM_S390_MEMOP_F_CHECK_ONLY | > + KVM_S390_MEMOP_F_SKEY_PROTECTION); > + if (r) > + return r; > + if (mop->ar >= NUM_ACRS) > return -EINVAL; > - if (mop->size > MEM_OP_MAX_SIZE) > - return -E2BIG; > if (kvm_s390_pv_cpu_is_protected(vcpu)) > return -EINVAL; > - if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { > - if (access_key_invalid(mop->key)) > - return -EINVAL; > - } else { > - mop->key = 0; > - } > - if (!(mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY)) { > - tmpbuf = vmalloc(mop->size); > - if (!tmpbuf) > - return -ENOMEM; > - } > + tmpbuf = mem_op_alloc_buf(mop); > + if (IS_ERR(tmpbuf)) > + return PTR_ERR(tmpbuf); > > switch (mop->op) { > case KVM_S390_MEMOP_LOGICAL_READ:
On 1/26/23 07:48, Thomas Huth wrote: > On 25/01/2023 22.26, Janis Schoetterl-Glausch wrote: >> The vcpu and vm mem_op ioctl implementations share some functionality. >> Move argument checking and buffer allocation into functions and call >> them from both implementations. >> This allows code reuse in case of additional future mem_op operations. >> >> Suggested-by: Janosch Frank <frankja@linux.ibm.com> >> Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com> >> --- >> arch/s390/kvm/kvm-s390.c | 80 +++++++++++++++++++++------------------- >> 1 file changed, 42 insertions(+), 38 deletions(-) >> >> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c >> index e4890e04b210..e0dfaa195949 100644 >> --- a/arch/s390/kvm/kvm-s390.c >> +++ b/arch/s390/kvm/kvm-s390.c >> @@ -2764,24 +2764,44 @@ static int kvm_s390_handle_pv(struct kvm *kvm, struct kvm_pv_cmd *cmd) >> return r; >> } >> >> -static bool access_key_invalid(u8 access_key) >> +static int mem_op_validate_common(struct kvm_s390_mem_op *mop, u64 supported_flags) >> { >> - return access_key > 0xf; >> + if (mop->flags & ~supported_flags || !mop->size) >> + return -EINVAL; >> + if (mop->size > MEM_OP_MAX_SIZE) >> + return -E2BIG; >> + if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { >> + if (mop->key > 0xf) >> + return -EINVAL; >> + } else { >> + mop->key = 0; >> + } >> + return 0; >> +} >> + >> +static void *mem_op_alloc_buf(struct kvm_s390_mem_op *mop) >> +{ >> + void *buf; >> + >> + if (mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY) >> + return NULL; >> + buf = vmalloc(mop->size); >> + if (!buf) >> + return ERR_PTR(-ENOMEM); >> + return buf; >> } >> >> static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) >> { >> void __user *uaddr = (void __user *)mop->buf; >> - u64 supported_flags; >> void *tmpbuf = NULL; > > You likely can now remove the "= NULL" here, I guess? > >> int r, srcu_idx; >> >> - supported_flags = KVM_S390_MEMOP_F_SKEY_PROTECTION >> - | KVM_S390_MEMOP_F_CHECK_ONLY; >> - if (mop->flags & ~supported_flags || !mop->size) >> - return -EINVAL; >> - if (mop->size > MEM_OP_MAX_SIZE) >> - return -E2BIG; >> + r = mem_op_validate_common(mop, KVM_S390_MEMOP_F_SKEY_PROTECTION | >> + KVM_S390_MEMOP_F_CHECK_ONLY); >> + if (r) >> + return r; >> + >> /* >> * This is technically a heuristic only, if the kvm->lock is not >> * taken, it is not guaranteed that the vm is/remains non-protected. >> @@ -2793,17 +2813,9 @@ static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) >> */ >> if (kvm_s390_pv_get_handle(kvm)) >> return -EINVAL; >> - if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { >> - if (access_key_invalid(mop->key)) >> - return -EINVAL; >> - } else { >> - mop->key = 0; >> - } >> - if (!(mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY)) { >> - tmpbuf = vmalloc(mop->size); >> - if (!tmpbuf) >> - return -ENOMEM; >> - } >> + tmpbuf = mem_op_alloc_buf(mop); >> + if (IS_ERR(tmpbuf)) >> + return PTR_ERR(tmpbuf); >> >> srcu_idx = srcu_read_lock(&kvm->srcu); >> >> @@ -5250,28 +5262,20 @@ static long kvm_s390_vcpu_mem_op(struct kvm_vcpu *vcpu, >> { >> void __user *uaddr = (void __user *)mop->buf; >> void *tmpbuf = NULL; > > ... and here, too. > > But I have to admit that I'm also not sure whether I like the > mem_op_alloc_buf() part or not (the mem_op_validate_common() part looks fine > to me) : mem_op_alloc_buf() is a new function with 11 lines of code, and the > old spots that allocate memory were only 5 lines of code each, so you now > increased the LoC count and additionally have to fiddly with IS_ERR and > PTR_ERR which is always a little bit ugly in my eyes ... IMHO I'd rather > keep the old code here. But that's just my 0.02 €, if you think it's nicer > with mem_op_alloc_buf(), I won't insist on keeping the old code. > > Thomas > I've done a PoC that has a **buff argument and combines the check with the alloc. @Nina: Any reason why this was split up?
On Thu, 2023-01-26 at 14:02 +0100, Janosch Frank wrote: > On 1/26/23 07:48, Thomas Huth wrote: > > On 25/01/2023 22.26, Janis Schoetterl-Glausch wrote: > > > The vcpu and vm mem_op ioctl implementations share some functionality. > > > Move argument checking and buffer allocation into functions and call > > > them from both implementations. > > > This allows code reuse in case of additional future mem_op operations. > > > > > > Suggested-by: Janosch Frank <frankja@linux.ibm.com> > > > Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com> > > > --- > > > arch/s390/kvm/kvm-s390.c | 80 +++++++++++++++++++++------------------- > > > 1 file changed, 42 insertions(+), 38 deletions(-) > > > > > > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c > > > index e4890e04b210..e0dfaa195949 100644 > > > --- a/arch/s390/kvm/kvm-s390.c > > > +++ b/arch/s390/kvm/kvm-s390.c > > > @@ -2764,24 +2764,44 @@ static int kvm_s390_handle_pv(struct kvm *kvm, struct kvm_pv_cmd *cmd) > > > return r; > > > } > > > > > > -static bool access_key_invalid(u8 access_key) > > > +static int mem_op_validate_common(struct kvm_s390_mem_op *mop, u64 supported_flags) > > > { > > > - return access_key > 0xf; > > > + if (mop->flags & ~supported_flags || !mop->size) > > > + return -EINVAL; > > > + if (mop->size > MEM_OP_MAX_SIZE) > > > + return -E2BIG; > > > + if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { > > > + if (mop->key > 0xf) > > > + return -EINVAL; > > > + } else { > > > + mop->key = 0; > > > + } > > > + return 0; > > > +} > > > + > > > +static void *mem_op_alloc_buf(struct kvm_s390_mem_op *mop) > > > +{ > > > + void *buf; > > > + > > > + if (mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY) > > > + return NULL; > > > + buf = vmalloc(mop->size); > > > + if (!buf) > > > + return ERR_PTR(-ENOMEM); > > > + return buf; > > > } > > > > > > static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) > > > { > > > void __user *uaddr = (void __user *)mop->buf; > > > - u64 supported_flags; > > > void *tmpbuf = NULL; > > > > You likely can now remove the "= NULL" here, I guess? > > > > > int r, srcu_idx; > > > > > > - supported_flags = KVM_S390_MEMOP_F_SKEY_PROTECTION > > > - | KVM_S390_MEMOP_F_CHECK_ONLY; > > > - if (mop->flags & ~supported_flags || !mop->size) > > > - return -EINVAL; > > > - if (mop->size > MEM_OP_MAX_SIZE) > > > - return -E2BIG; > > > + r = mem_op_validate_common(mop, KVM_S390_MEMOP_F_SKEY_PROTECTION | > > > + KVM_S390_MEMOP_F_CHECK_ONLY); > > > + if (r) > > > + return r; > > > + > > > /* > > > * This is technically a heuristic only, if the kvm->lock is not > > > * taken, it is not guaranteed that the vm is/remains non-protected. > > > @@ -2793,17 +2813,9 @@ static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) > > > */ > > > if (kvm_s390_pv_get_handle(kvm)) > > > return -EINVAL; > > > - if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { > > > - if (access_key_invalid(mop->key)) > > > - return -EINVAL; > > > - } else { > > > - mop->key = 0; > > > - } > > > - if (!(mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY)) { > > > - tmpbuf = vmalloc(mop->size); > > > - if (!tmpbuf) > > > - return -ENOMEM; > > > - } > > > + tmpbuf = mem_op_alloc_buf(mop); > > > + if (IS_ERR(tmpbuf)) > > > + return PTR_ERR(tmpbuf); > > > > > > srcu_idx = srcu_read_lock(&kvm->srcu); > > > > > > @@ -5250,28 +5262,20 @@ static long kvm_s390_vcpu_mem_op(struct kvm_vcpu *vcpu, > > > { > > > void __user *uaddr = (void __user *)mop->buf; > > > void *tmpbuf = NULL; > > > > ... and here, too. > > > > But I have to admit that I'm also not sure whether I like the > > mem_op_alloc_buf() part or not (the mem_op_validate_common() part looks fine > > to me) : mem_op_alloc_buf() is a new function with 11 lines of code, and the > > old spots that allocate memory were only 5 lines of code each, so you now > > increased the LoC count and additionally have to fiddly with IS_ERR and > > PTR_ERR which is always a little bit ugly in my eyes ... IMHO I'd rather > > keep the old code here. But that's just my 0.02 €, if you think it's nicer > > with mem_op_alloc_buf(), I won't insist on keeping the old code. > > > > Thomas > > > > I've done a PoC that has a **buff argument and combines the check with > the alloc. I just didn't like that much because it felt like an unspecific memop_do_things function.
On Thu, 2023-01-26 at 07:48 +0100, Thomas Huth wrote: > On 25/01/2023 22.26, Janis Schoetterl-Glausch wrote: > > The vcpu and vm mem_op ioctl implementations share some functionality. > > Move argument checking and buffer allocation into functions and call > > them from both implementations. > > This allows code reuse in case of additional future mem_op operations. > > > > Suggested-by: Janosch Frank <frankja@linux.ibm.com> > > Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com> > > --- > > arch/s390/kvm/kvm-s390.c | 80 +++++++++++++++++++++------------------- > > 1 file changed, 42 insertions(+), 38 deletions(-) > > > > diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c > > index e4890e04b210..e0dfaa195949 100644 > > --- a/arch/s390/kvm/kvm-s390.c > > +++ b/arch/s390/kvm/kvm-s390.c > > @@ -2764,24 +2764,44 @@ static int kvm_s390_handle_pv(struct kvm *kvm, struct kvm_pv_cmd *cmd) > > return r; > > } > > > > -static bool access_key_invalid(u8 access_key) > > +static int mem_op_validate_common(struct kvm_s390_mem_op *mop, u64 supported_flags) > > { > > - return access_key > 0xf; > > + if (mop->flags & ~supported_flags || !mop->size) > > + return -EINVAL; > > + if (mop->size > MEM_OP_MAX_SIZE) > > + return -E2BIG; > > + if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { > > + if (mop->key > 0xf) > > + return -EINVAL; > > + } else { > > + mop->key = 0; > > + } > > + return 0; > > +} > > + > > +static void *mem_op_alloc_buf(struct kvm_s390_mem_op *mop) > > +{ > > + void *buf; > > + > > + if (mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY) > > + return NULL; > > + buf = vmalloc(mop->size); > > + if (!buf) > > + return ERR_PTR(-ENOMEM); > > + return buf; > > } > > > > static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) > > { > > void __user *uaddr = (void __user *)mop->buf; > > - u64 supported_flags; > > void *tmpbuf = NULL; > > You likely can now remove the "= NULL" here, I guess? Yeah, I thought about it, but wasn't sure if I like moving the line down because of some people's insistence on reverse christmas tree. It's entirely arbitrary in a different way, but I like the return value being the last thing declared. In the end I forgot to make a decision on it. > > > int r, srcu_idx; > > > > - supported_flags = KVM_S390_MEMOP_F_SKEY_PROTECTION > > - | KVM_S390_MEMOP_F_CHECK_ONLY; > > - if (mop->flags & ~supported_flags || !mop->size) > > - return -EINVAL; > > - if (mop->size > MEM_OP_MAX_SIZE) > > - return -E2BIG; > > + r = mem_op_validate_common(mop, KVM_S390_MEMOP_F_SKEY_PROTECTION | > > + KVM_S390_MEMOP_F_CHECK_ONLY); > > + if (r) > > + return r; > > + > > /* > > * This is technically a heuristic only, if the kvm->lock is not > > * taken, it is not guaranteed that the vm is/remains non-protected. > > @@ -2793,17 +2813,9 @@ static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) > > */ > > if (kvm_s390_pv_get_handle(kvm)) > > return -EINVAL; > > - if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { > > - if (access_key_invalid(mop->key)) > > - return -EINVAL; > > - } else { > > - mop->key = 0; > > - } > > - if (!(mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY)) { > > - tmpbuf = vmalloc(mop->size); > > - if (!tmpbuf) > > - return -ENOMEM; > > - } > > + tmpbuf = mem_op_alloc_buf(mop); > > + if (IS_ERR(tmpbuf)) > > + return PTR_ERR(tmpbuf); > > > > srcu_idx = srcu_read_lock(&kvm->srcu); > > > > @@ -5250,28 +5262,20 @@ static long kvm_s390_vcpu_mem_op(struct kvm_vcpu *vcpu, > > { > > void __user *uaddr = (void __user *)mop->buf; > > void *tmpbuf = NULL; > > ... and here, too. > > But I have to admit that I'm also not sure whether I like the > mem_op_alloc_buf() part or not (the mem_op_validate_common() part looks fine > to me) : mem_op_alloc_buf() is a new function with 11 lines of code, and the > old spots that allocate memory were only 5 lines of code each, so you now > increased the LoC count and additionally have to fiddly with IS_ERR and > PTR_ERR which is always a little bit ugly in my eyes ... IMHO I'd rather > keep the old code here. But that's just my 0.02 €, if you think it's nicer > with mem_op_alloc_buf(), I won't insist on keeping the old code. Yeah, that's fair. > > Thomas > > > > - int r = 0; > > - const u64 supported_flags = KVM_S390_MEMOP_F_INJECT_EXCEPTION > > - | KVM_S390_MEMOP_F_CHECK_ONLY > > - | KVM_S390_MEMOP_F_SKEY_PROTECTION; > > + int r; > > > > - if (mop->flags & ~supported_flags || mop->ar >= NUM_ACRS || !mop->size) > > + r = mem_op_validate_common(mop, KVM_S390_MEMOP_F_INJECT_EXCEPTION | > > + KVM_S390_MEMOP_F_CHECK_ONLY | > > + KVM_S390_MEMOP_F_SKEY_PROTECTION); > > + if (r) > > + return r; > > + if (mop->ar >= NUM_ACRS) > > return -EINVAL; > > - if (mop->size > MEM_OP_MAX_SIZE) > > - return -E2BIG; > > if (kvm_s390_pv_cpu_is_protected(vcpu)) > > return -EINVAL; > > - if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { > > - if (access_key_invalid(mop->key)) > > - return -EINVAL; > > - } else { > > - mop->key = 0; > > - } > > - if (!(mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY)) { > > - tmpbuf = vmalloc(mop->size); > > - if (!tmpbuf) > > - return -ENOMEM; > > - } > > + tmpbuf = mem_op_alloc_buf(mop); > > + if (IS_ERR(tmpbuf)) > > + return PTR_ERR(tmpbuf); > > > > switch (mop->op) { > > case KVM_S390_MEMOP_LOGICAL_READ: >
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index e4890e04b210..e0dfaa195949 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -2764,24 +2764,44 @@ static int kvm_s390_handle_pv(struct kvm *kvm, struct kvm_pv_cmd *cmd) return r; } -static bool access_key_invalid(u8 access_key) +static int mem_op_validate_common(struct kvm_s390_mem_op *mop, u64 supported_flags) { - return access_key > 0xf; + if (mop->flags & ~supported_flags || !mop->size) + return -EINVAL; + if (mop->size > MEM_OP_MAX_SIZE) + return -E2BIG; + if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { + if (mop->key > 0xf) + return -EINVAL; + } else { + mop->key = 0; + } + return 0; +} + +static void *mem_op_alloc_buf(struct kvm_s390_mem_op *mop) +{ + void *buf; + + if (mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY) + return NULL; + buf = vmalloc(mop->size); + if (!buf) + return ERR_PTR(-ENOMEM); + return buf; } static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) { void __user *uaddr = (void __user *)mop->buf; - u64 supported_flags; void *tmpbuf = NULL; int r, srcu_idx; - supported_flags = KVM_S390_MEMOP_F_SKEY_PROTECTION - | KVM_S390_MEMOP_F_CHECK_ONLY; - if (mop->flags & ~supported_flags || !mop->size) - return -EINVAL; - if (mop->size > MEM_OP_MAX_SIZE) - return -E2BIG; + r = mem_op_validate_common(mop, KVM_S390_MEMOP_F_SKEY_PROTECTION | + KVM_S390_MEMOP_F_CHECK_ONLY); + if (r) + return r; + /* * This is technically a heuristic only, if the kvm->lock is not * taken, it is not guaranteed that the vm is/remains non-protected. @@ -2793,17 +2813,9 @@ static int kvm_s390_vm_mem_op(struct kvm *kvm, struct kvm_s390_mem_op *mop) */ if (kvm_s390_pv_get_handle(kvm)) return -EINVAL; - if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { - if (access_key_invalid(mop->key)) - return -EINVAL; - } else { - mop->key = 0; - } - if (!(mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY)) { - tmpbuf = vmalloc(mop->size); - if (!tmpbuf) - return -ENOMEM; - } + tmpbuf = mem_op_alloc_buf(mop); + if (IS_ERR(tmpbuf)) + return PTR_ERR(tmpbuf); srcu_idx = srcu_read_lock(&kvm->srcu); @@ -5250,28 +5262,20 @@ static long kvm_s390_vcpu_mem_op(struct kvm_vcpu *vcpu, { void __user *uaddr = (void __user *)mop->buf; void *tmpbuf = NULL; - int r = 0; - const u64 supported_flags = KVM_S390_MEMOP_F_INJECT_EXCEPTION - | KVM_S390_MEMOP_F_CHECK_ONLY - | KVM_S390_MEMOP_F_SKEY_PROTECTION; + int r; - if (mop->flags & ~supported_flags || mop->ar >= NUM_ACRS || !mop->size) + r = mem_op_validate_common(mop, KVM_S390_MEMOP_F_INJECT_EXCEPTION | + KVM_S390_MEMOP_F_CHECK_ONLY | + KVM_S390_MEMOP_F_SKEY_PROTECTION); + if (r) + return r; + if (mop->ar >= NUM_ACRS) return -EINVAL; - if (mop->size > MEM_OP_MAX_SIZE) - return -E2BIG; if (kvm_s390_pv_cpu_is_protected(vcpu)) return -EINVAL; - if (mop->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) { - if (access_key_invalid(mop->key)) - return -EINVAL; - } else { - mop->key = 0; - } - if (!(mop->flags & KVM_S390_MEMOP_F_CHECK_ONLY)) { - tmpbuf = vmalloc(mop->size); - if (!tmpbuf) - return -ENOMEM; - } + tmpbuf = mem_op_alloc_buf(mop); + if (IS_ERR(tmpbuf)) + return PTR_ERR(tmpbuf); switch (mop->op) { case KVM_S390_MEMOP_LOGICAL_READ:
The vcpu and vm mem_op ioctl implementations share some functionality. Move argument checking and buffer allocation into functions and call them from both implementations. This allows code reuse in case of additional future mem_op operations. Suggested-by: Janosch Frank <frankja@linux.ibm.com> Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com> --- arch/s390/kvm/kvm-s390.c | 80 +++++++++++++++++++++------------------- 1 file changed, 42 insertions(+), 38 deletions(-)