From: Christoffer Dall <christoffer.dall@linaro.org> To: vijay.kilari@gmail.com Cc: kvm@vger.kernel.org, Marc Zyngier <marc.zyngier@arm.com>, Andre Przywara <andre.przywara@arm.com>, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org Subject: [PATCH v2 1/2] KVM: arm/arm64: Factor out vgic_attr_regs_access functionality Date: Tue, 16 Aug 2016 19:35:00 +0200 [thread overview] Message-ID: <20160816173501.21521-2-christoffer.dall@linaro.org> (raw) In-Reply-To: <20160816173501.21521-1-christoffer.dall@linaro.org> As we are about to deal with multiple data types and situations where the vgic should not be initialized when doing userspace accesses on the register attributes, factor out the functionality of vgic_attr_regs_access into smaller bits which can be reused by a new function later. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> --- virt/kvm/arm/vgic/vgic-kvm-device.c | 100 ++++++++++++++++++++++++++---------- 1 file changed, 73 insertions(+), 27 deletions(-) diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c index 1813f93..19fa331 100644 --- a/virt/kvm/arm/vgic/vgic-kvm-device.c +++ b/virt/kvm/arm/vgic/vgic-kvm-device.c @@ -233,6 +233,67 @@ int kvm_register_vgic_device(unsigned long type) return ret; } +struct vgic_reg_attr { + struct kvm_vcpu *vcpu; + gpa_t addr; +}; + +static int parse_vgic_v2_attr(struct kvm_device *dev, + struct kvm_device_attr *attr, + struct vgic_reg_attr *reg_attr) +{ + int cpuid; + + cpuid = (attr->attr & KVM_DEV_ARM_VGIC_CPUID_MASK) >> + KVM_DEV_ARM_VGIC_CPUID_SHIFT; + + if (cpuid >= atomic_read(&dev->kvm->online_vcpus)) + return -EINVAL; + + reg_attr->vcpu = kvm_get_vcpu(dev->kvm, cpuid); + reg_attr->addr = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK; + + return 0; +} + +/* unlocks vcpus from @vcpu_lock_idx and smaller */ +static void unlock_vcpus(struct kvm *kvm, int vcpu_lock_idx) +{ + struct kvm_vcpu *tmp_vcpu; + + for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) { + tmp_vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx); + mutex_unlock(&tmp_vcpu->mutex); + } +} + +static void unlock_all_vcpus(struct kvm *kvm) +{ + unlock_vcpus(kvm, atomic_read(&kvm->online_vcpus) - 1); +} + +/* Returns true if all vcpus were locked, false otherwise */ +static bool lock_all_vcpus(struct kvm *kvm) +{ + struct kvm_vcpu *tmp_vcpu; + int c; + + /* + * Any time a vcpu is run, vcpu_load is called which tries to grab the + * vcpu->mutex. By grabbing the vcpu->mutex of all VCPUs we ensure + * that no other VCPUs are run and fiddle with the vgic state while we + * access it. + */ + kvm_for_each_vcpu(c, tmp_vcpu, kvm) { + if (!mutex_trylock(&tmp_vcpu->mutex)) { + unlock_vcpus(kvm, c - 1); + return false; + } + } + + return true; +} + /** vgic_attr_regs_access: allows user space to read/write VGIC registers * * @dev: kvm device handle @@ -245,15 +306,17 @@ static int vgic_attr_regs_access(struct kvm_device *dev, struct kvm_device_attr *attr, u32 *reg, bool is_write) { + struct vgic_reg_attr reg_attr; gpa_t addr; - int cpuid, ret, c; - struct kvm_vcpu *vcpu, *tmp_vcpu; - int vcpu_lock_idx = -1; + struct kvm_vcpu *vcpu; + int ret; - cpuid = (attr->attr & KVM_DEV_ARM_VGIC_CPUID_MASK) >> - KVM_DEV_ARM_VGIC_CPUID_SHIFT; - vcpu = kvm_get_vcpu(dev->kvm, cpuid); - addr = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK; + ret = parse_vgic_v2_attr(dev, attr, ®_attr); + if (ret) + return ret; + + vcpu = reg_attr.vcpu; + addr = reg_attr.addr; mutex_lock(&dev->kvm->lock); @@ -261,24 +324,11 @@ static int vgic_attr_regs_access(struct kvm_device *dev, if (ret) goto out; - if (cpuid >= atomic_read(&dev->kvm->online_vcpus)) { - ret = -EINVAL; + if (!lock_all_vcpus(dev->kvm)) { + ret = -EBUSY; goto out; } - /* - * Any time a vcpu is run, vcpu_load is called which tries to grab the - * vcpu->mutex. By grabbing the vcpu->mutex of all VCPUs we ensure - * that no other VCPUs are run and fiddle with the vgic state while we - * access it. - */ - ret = -EBUSY; - kvm_for_each_vcpu(c, tmp_vcpu, dev->kvm) { - if (!mutex_trylock(&tmp_vcpu->mutex)) - goto out; - vcpu_lock_idx = c; - } - switch (attr->group) { case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: ret = vgic_v2_cpuif_uaccess(vcpu, is_write, addr, reg); @@ -291,12 +341,8 @@ static int vgic_attr_regs_access(struct kvm_device *dev, break; } + unlock_all_vcpus(dev->kvm); out: - for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) { - tmp_vcpu = kvm_get_vcpu(dev->kvm, vcpu_lock_idx); - mutex_unlock(&tmp_vcpu->mutex); - } - mutex_unlock(&dev->kvm->lock); return ret; } -- 2.9.0
WARNING: multiple messages have this Message-ID (diff)
From: christoffer.dall@linaro.org (Christoffer Dall) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v2 1/2] KVM: arm/arm64: Factor out vgic_attr_regs_access functionality Date: Tue, 16 Aug 2016 19:35:00 +0200 [thread overview] Message-ID: <20160816173501.21521-2-christoffer.dall@linaro.org> (raw) In-Reply-To: <20160816173501.21521-1-christoffer.dall@linaro.org> As we are about to deal with multiple data types and situations where the vgic should not be initialized when doing userspace accesses on the register attributes, factor out the functionality of vgic_attr_regs_access into smaller bits which can be reused by a new function later. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> --- virt/kvm/arm/vgic/vgic-kvm-device.c | 100 ++++++++++++++++++++++++++---------- 1 file changed, 73 insertions(+), 27 deletions(-) diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c index 1813f93..19fa331 100644 --- a/virt/kvm/arm/vgic/vgic-kvm-device.c +++ b/virt/kvm/arm/vgic/vgic-kvm-device.c @@ -233,6 +233,67 @@ int kvm_register_vgic_device(unsigned long type) return ret; } +struct vgic_reg_attr { + struct kvm_vcpu *vcpu; + gpa_t addr; +}; + +static int parse_vgic_v2_attr(struct kvm_device *dev, + struct kvm_device_attr *attr, + struct vgic_reg_attr *reg_attr) +{ + int cpuid; + + cpuid = (attr->attr & KVM_DEV_ARM_VGIC_CPUID_MASK) >> + KVM_DEV_ARM_VGIC_CPUID_SHIFT; + + if (cpuid >= atomic_read(&dev->kvm->online_vcpus)) + return -EINVAL; + + reg_attr->vcpu = kvm_get_vcpu(dev->kvm, cpuid); + reg_attr->addr = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK; + + return 0; +} + +/* unlocks vcpus from @vcpu_lock_idx and smaller */ +static void unlock_vcpus(struct kvm *kvm, int vcpu_lock_idx) +{ + struct kvm_vcpu *tmp_vcpu; + + for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) { + tmp_vcpu = kvm_get_vcpu(kvm, vcpu_lock_idx); + mutex_unlock(&tmp_vcpu->mutex); + } +} + +static void unlock_all_vcpus(struct kvm *kvm) +{ + unlock_vcpus(kvm, atomic_read(&kvm->online_vcpus) - 1); +} + +/* Returns true if all vcpus were locked, false otherwise */ +static bool lock_all_vcpus(struct kvm *kvm) +{ + struct kvm_vcpu *tmp_vcpu; + int c; + + /* + * Any time a vcpu is run, vcpu_load is called which tries to grab the + * vcpu->mutex. By grabbing the vcpu->mutex of all VCPUs we ensure + * that no other VCPUs are run and fiddle with the vgic state while we + * access it. + */ + kvm_for_each_vcpu(c, tmp_vcpu, kvm) { + if (!mutex_trylock(&tmp_vcpu->mutex)) { + unlock_vcpus(kvm, c - 1); + return false; + } + } + + return true; +} + /** vgic_attr_regs_access: allows user space to read/write VGIC registers * * @dev: kvm device handle @@ -245,15 +306,17 @@ static int vgic_attr_regs_access(struct kvm_device *dev, struct kvm_device_attr *attr, u32 *reg, bool is_write) { + struct vgic_reg_attr reg_attr; gpa_t addr; - int cpuid, ret, c; - struct kvm_vcpu *vcpu, *tmp_vcpu; - int vcpu_lock_idx = -1; + struct kvm_vcpu *vcpu; + int ret; - cpuid = (attr->attr & KVM_DEV_ARM_VGIC_CPUID_MASK) >> - KVM_DEV_ARM_VGIC_CPUID_SHIFT; - vcpu = kvm_get_vcpu(dev->kvm, cpuid); - addr = attr->attr & KVM_DEV_ARM_VGIC_OFFSET_MASK; + ret = parse_vgic_v2_attr(dev, attr, ®_attr); + if (ret) + return ret; + + vcpu = reg_attr.vcpu; + addr = reg_attr.addr; mutex_lock(&dev->kvm->lock); @@ -261,24 +324,11 @@ static int vgic_attr_regs_access(struct kvm_device *dev, if (ret) goto out; - if (cpuid >= atomic_read(&dev->kvm->online_vcpus)) { - ret = -EINVAL; + if (!lock_all_vcpus(dev->kvm)) { + ret = -EBUSY; goto out; } - /* - * Any time a vcpu is run, vcpu_load is called which tries to grab the - * vcpu->mutex. By grabbing the vcpu->mutex of all VCPUs we ensure - * that no other VCPUs are run and fiddle with the vgic state while we - * access it. - */ - ret = -EBUSY; - kvm_for_each_vcpu(c, tmp_vcpu, dev->kvm) { - if (!mutex_trylock(&tmp_vcpu->mutex)) - goto out; - vcpu_lock_idx = c; - } - switch (attr->group) { case KVM_DEV_ARM_VGIC_GRP_CPU_REGS: ret = vgic_v2_cpuif_uaccess(vcpu, is_write, addr, reg); @@ -291,12 +341,8 @@ static int vgic_attr_regs_access(struct kvm_device *dev, break; } + unlock_all_vcpus(dev->kvm); out: - for (; vcpu_lock_idx >= 0; vcpu_lock_idx--) { - tmp_vcpu = kvm_get_vcpu(dev->kvm, vcpu_lock_idx); - mutex_unlock(&tmp_vcpu->mutex); - } - mutex_unlock(&dev->kvm->lock); return ret; } -- 2.9.0
next prev parent reply other threads:[~2016-08-16 17:35 UTC|newest] Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top 2016-08-16 17:34 [PATCH v2 0/2] Rework vgic_attr_regs_access Christoffer Dall 2016-08-16 17:34 ` Christoffer Dall 2016-08-16 17:35 ` Christoffer Dall [this message] 2016-08-16 17:35 ` [PATCH v2 1/2] KVM: arm/arm64: Factor out vgic_attr_regs_access functionality Christoffer Dall 2016-08-17 5:46 ` Auger Eric 2016-08-17 5:46 ` Auger Eric 2016-08-16 17:35 ` [PATCH v2 2/2] KVM: arm/arm64: Rename vgic_attr_regs_access to vgic_attr_regs_access_v2 Christoffer Dall 2016-08-16 17:35 ` Christoffer Dall 2016-08-17 5:46 ` Auger Eric 2016-08-17 5:46 ` Auger Eric
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20160816173501.21521-2-christoffer.dall@linaro.org \ --to=christoffer.dall@linaro.org \ --cc=andre.przywara@arm.com \ --cc=kvm@vger.kernel.org \ --cc=kvmarm@lists.cs.columbia.edu \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=marc.zyngier@arm.com \ --cc=vijay.kilari@gmail.com \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.