Simplify the error paths in snp_launch_update() by using a mutex guard, allowing early return instead of using gotos. Signed-off-by: Carlos López --- arch/x86/kvm/svm/sev.c | 32 +++++++++++++------------------- 1 file changed, 13 insertions(+), 19 deletions(-) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index f59c65abe3cf..1b325ae61d15 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -8,6 +8,7 @@ */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include #include #include #include @@ -2367,7 +2368,6 @@ static int snp_launch_update(struct kvm *kvm, struct kvm_sev_cmd *argp) struct kvm_memory_slot *memslot; long npages, count; void __user *src; - int ret = 0; if (!sev_snp_guest(kvm) || !sev->snp_context) return -EINVAL; @@ -2407,13 +2407,11 @@ static int snp_launch_update(struct kvm *kvm, struct kvm_sev_cmd *argp) * initial expected state and better guard against unexpected * situations. */ - mutex_lock(&kvm->slots_lock); + guard(mutex)(&kvm->slots_lock); memslot = gfn_to_memslot(kvm, params.gfn_start); - if (!kvm_slot_has_gmem(memslot)) { - ret = -EINVAL; - goto out; - } + if (!kvm_slot_has_gmem(memslot)) + return -EINVAL; sev_populate_args.sev_fd = argp->sev_fd; sev_populate_args.type = params.type; @@ -2425,22 +2423,18 @@ static int snp_launch_update(struct kvm *kvm, struct kvm_sev_cmd *argp) argp->error = sev_populate_args.fw_error; pr_debug("%s: kvm_gmem_populate failed, ret %ld (fw_error %d)\n", __func__, count, argp->error); - ret = -EIO; - } else { - params.gfn_start += count; - params.len -= count * PAGE_SIZE; - if (params.type != KVM_SEV_SNP_PAGE_TYPE_ZERO) - params.uaddr += count * PAGE_SIZE; - - ret = 0; - if (copy_to_user(u64_to_user_ptr(argp->data), ¶ms, sizeof(params))) - ret = -EFAULT; + return -EIO; } -out: - mutex_unlock(&kvm->slots_lock); + params.gfn_start += count; + params.len -= count * PAGE_SIZE; + if (params.type != KVM_SEV_SNP_PAGE_TYPE_ZERO) + params.uaddr += count * PAGE_SIZE; - return ret; + if (copy_to_user(u64_to_user_ptr(argp->data), ¶ms, sizeof(params))) + return -EFAULT; + + return 0; } static int snp_launch_update_vmsa(struct kvm *kvm, struct kvm_sev_cmd *argp) -- 2.51.0