| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Thu, 21 Apr 2022 19:13:29 +0800
From: "Zhu, Lingshan" <lingshan.zhu@...el.com>
To: "Michael S. Tsirkin" <mst@...hat.com>,
Jason Wang <jasowang@...hat.com>
Cc: virtualization <virtualization@...ts.linux-foundation.org>,
netdev <netdev@...r.kernel.org>
Subject: Re: [PATCH] vDPA/ifcvf: allow userspace to suspend a queue
On 4/13/2022 4:54 PM, Michael S. Tsirkin wrote:
> On Wed, Apr 13, 2022 at 04:25:22PM +0800, Jason Wang wrote:
>> On Mon, Apr 11, 2022 at 11:18 AM Zhu Lingshan <lingshan.zhu@...el.com> wrote:
>>> Formerly, ifcvf driver has implemented a lazy-initialization mechanism
>>> for the virtqueues, it would store all virtqueue config fields that
>>> passed down from the userspace, then load them to the virtqueues and
>>> enable the queues upon DRIVER_OK.
>>>
>>> To allow the userspace to suspend a virtqueue,
>>> this commit passes queue_enable to the virtqueue directly through
>>> set_vq_ready().
>>>
>>> This feature requires and this commits implementing all virtqueue
>>> ops(set_vq_addr, set_vq_num and set_vq_ready) to take immediate
>>> actions than lazy-initialization, so ifcvf_hw_enable() is retired.
>>>
>>> To avoid losing virtqueue configurations caused by multiple
>>> rounds of reset(), this commit also refactors thed evice reset
>>> routine, now it simply reset the config handler and the virtqueues,
>>> and only once device-reset().
>>>
>>> Signed-off-by: Zhu Lingshan <lingshan.zhu@...el.com>
>>> ---
>>> drivers/vdpa/ifcvf/ifcvf_base.c | 94 ++++++++++++++++++++-------------
>>> drivers/vdpa/ifcvf/ifcvf_base.h | 11 ++--
>>> drivers/vdpa/ifcvf/ifcvf_main.c | 57 +++++---------------
>>> 3 files changed, 75 insertions(+), 87 deletions(-)
>>>
>>> diff --git a/drivers/vdpa/ifcvf/ifcvf_base.c b/drivers/vdpa/ifcvf/ifcvf_base.c
>>> index 48c4dadb0c7c..19eb0dcac123 100644
>>> --- a/drivers/vdpa/ifcvf/ifcvf_base.c
>>> +++ b/drivers/vdpa/ifcvf/ifcvf_base.c
>>> @@ -175,16 +175,12 @@ u8 ifcvf_get_status(struct ifcvf_hw *hw)
>>> void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
>>> {
>>> vp_iowrite8(status, &hw->common_cfg->device_status);
>>> + vp_ioread8(&hw->common_cfg->device_status);
>> This looks confusing, the name of the function is to set the status
>> but what actually implemented here is to get the status.
>>
>>> }
>>>
>>> void ifcvf_reset(struct ifcvf_hw *hw)
>>> {
>>> - hw->config_cb.callback = NULL;
>>> - hw->config_cb.private = NULL;
>>> -
>>> ifcvf_set_status(hw, 0);
>>> - /* flush set_status, make sure VF is stopped, reset */
>>> - ifcvf_get_status(hw);
>>> }
>>>
>>> static void ifcvf_add_status(struct ifcvf_hw *hw, u8 status)
>>> @@ -331,68 +327,94 @@ int ifcvf_set_vq_state(struct ifcvf_hw *hw, u16 qid, u16 num)
>>> ifcvf_lm = (struct ifcvf_lm_cfg __iomem *)hw->lm_cfg;
>>> q_pair_id = qid / hw->nr_vring;
>>> avail_idx_addr = &ifcvf_lm->vring_lm_cfg[q_pair_id].idx_addr[qid % 2];
>>> - hw->vring[qid].last_avail_idx = num;
>>> vp_iowrite16(num, avail_idx_addr);
>>> + vp_ioread16(avail_idx_addr);
>> This looks like a bug fix.
> is this to flush out the status write? pls add a comment
> explaining when and why it's needed.
I think this may not needed anymore, setting DRIVER_OK will flush them all,
so all extra flush are removed.
>
>>> return 0;
>>> }
>>>
>>> -static int ifcvf_hw_enable(struct ifcvf_hw *hw)
>>> +void ifcvf_set_vq_num(struct ifcvf_hw *hw, u16 qid, u32 num)
>>> {
>>> - struct virtio_pci_common_cfg __iomem *cfg;
>>> - u32 i;
>>> + struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
>>>
>>> - cfg = hw->common_cfg;
>>> - for (i = 0; i < hw->nr_vring; i++) {
>>> - if (!hw->vring[i].ready)
>>> - break;
>>> + vp_iowrite16(qid, &cfg->queue_select);
>>> + vp_iowrite16(num, &cfg->queue_size);
>>> + vp_ioread16(&cfg->queue_size);
>>> +}
>>>
>>> - vp_iowrite16(i, &cfg->queue_select);
>>> - vp_iowrite64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
>>> - &cfg->queue_desc_hi);
>>> - vp_iowrite64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
>>> - &cfg->queue_avail_hi);
>>> - vp_iowrite64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
>>> - &cfg->queue_used_hi);
>>> - vp_iowrite16(hw->vring[i].size, &cfg->queue_size);
>>> - ifcvf_set_vq_state(hw, i, hw->vring[i].last_avail_idx);
>>> - vp_iowrite16(1, &cfg->queue_enable);
>>> - }
>>> +int ifcvf_set_vq_address(struct ifcvf_hw *hw, u16 qid, u64 desc_area,
>>> + u64 driver_area, u64 device_area)
>>> +{
>>> + struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
>>> +
>>> + vp_iowrite16(qid, &cfg->queue_select);
>>> + vp_iowrite64_twopart(desc_area, &cfg->queue_desc_lo,
>>> + &cfg->queue_desc_hi);
>>> + vp_iowrite64_twopart(driver_area, &cfg->queue_avail_lo,
>>> + &cfg->queue_avail_hi);
>>> + vp_iowrite64_twopart(device_area, &cfg->queue_used_lo,
>>> + &cfg->queue_used_hi);
>>> + /* to flush IO */
>>> + vp_ioread16(&cfg->queue_select);
>> Why do we need to flush I/O here?
>>
>>> return 0;
>>> }
>>>
>>> -static void ifcvf_hw_disable(struct ifcvf_hw *hw)
>>> +void ifcvf_set_vq_ready(struct ifcvf_hw *hw, u16 qid, bool ready)
>>> {
>>> - u32 i;
>>> + struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
>>>
>>> - ifcvf_set_config_vector(hw, VIRTIO_MSI_NO_VECTOR);
>>> - for (i = 0; i < hw->nr_vring; i++) {
>>> - ifcvf_set_vq_vector(hw, i, VIRTIO_MSI_NO_VECTOR);
>>> - }
>>> + vp_iowrite16(qid, &cfg->queue_select);
>>> + vp_iowrite16(ready, &cfg->queue_enable);
>> I think we need a comment to explain that IFCVF can support write to
>> queue_enable since it's not allowed by the virtio spec.
>
> I think you mean writing 0 there. writing 1 is allowed.
I have added a comment here says writing 0 would suspend the queue.
>
>
>>> + vp_ioread16(&cfg->queue_enable);
>>> +}
>>> +
>>> +bool ifcvf_get_vq_ready(struct ifcvf_hw *hw, u16 qid)
>>> +{
>>> + struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
>>> + bool queue_enable;
>>> +
>>> + vp_iowrite16(qid, &cfg->queue_select);
>>> + queue_enable = vp_ioread16(&cfg->queue_enable);
>>> +
>>> + return (bool)queue_enable;
>>> }
>>>
>>> int ifcvf_start_hw(struct ifcvf_hw *hw)
>>> {
>>> - ifcvf_reset(hw);
>>> ifcvf_add_status(hw, VIRTIO_CONFIG_S_ACKNOWLEDGE);
>>> ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER);
>>>
>>> if (ifcvf_config_features(hw) < 0)
>>> return -EINVAL;
>>>
>>> - if (ifcvf_hw_enable(hw) < 0)
>>> - return -EINVAL;
>>> -
>>> ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER_OK);
>>>
>>> return 0;
>>> }
>>>
>>> +static void ifcvf_reset_vring(struct ifcvf_hw *hw)
>>> +{
>>> + int i;
>>> +
>>> + for (i = 0; i < hw->nr_vring; i++) {
>>> + hw->vring[i].cb.callback = NULL;
>>> + hw->vring[i].cb.private = NULL;
>>> + ifcvf_set_vq_vector(hw, i, VIRTIO_MSI_NO_VECTOR);
>>> + }
>>> +}
>>> +
>>> +static void ifcvf_reset_config_handler(struct ifcvf_hw *hw)
>>> +{
>>> + hw->config_cb.callback = NULL;
>>> + hw->config_cb.private = NULL;
>>> + ifcvf_set_config_vector(hw, VIRTIO_MSI_NO_VECTOR);
>> Do we need to synchronize with the IRQ here?
>>
>>> +}
>>> +
>>> void ifcvf_stop_hw(struct ifcvf_hw *hw)
>>> {
>>> - ifcvf_hw_disable(hw);
>>> - ifcvf_reset(hw);
>>> + ifcvf_reset_vring(hw);
>>> + ifcvf_reset_config_handler(hw);
>>> }
>>>
>>> void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid)
>>> diff --git a/drivers/vdpa/ifcvf/ifcvf_base.h b/drivers/vdpa/ifcvf/ifcvf_base.h
>>> index 115b61f4924b..41d86985361f 100644
>>> --- a/drivers/vdpa/ifcvf/ifcvf_base.h
>>> +++ b/drivers/vdpa/ifcvf/ifcvf_base.h
>>> @@ -49,12 +49,6 @@
>>> #define MSIX_VECTOR_DEV_SHARED 3
>>>
>>> struct vring_info {
>>> - u64 desc;
>>> - u64 avail;
>>> - u64 used;
>>> - u16 size;
>>> - u16 last_avail_idx;
>>> - bool ready;
>>> void __iomem *notify_addr;
>>> phys_addr_t notify_pa;
>>> u32 irq;
>>> @@ -131,6 +125,11 @@ int ifcvf_set_vq_state(struct ifcvf_hw *hw, u16 qid, u16 num);
>>> struct ifcvf_adapter *vf_to_adapter(struct ifcvf_hw *hw);
>>> int ifcvf_probed_virtio_net(struct ifcvf_hw *hw);
>>> u32 ifcvf_get_config_size(struct ifcvf_hw *hw);
>>> +int ifcvf_set_vq_address(struct ifcvf_hw *hw, u16 qid, u64 desc_area,
>>> + u64 driver_area, u64 device_area);
>>> u16 ifcvf_set_vq_vector(struct ifcvf_hw *hw, u16 qid, int vector);
>>> u16 ifcvf_set_config_vector(struct ifcvf_hw *hw, int vector);
>>> +void ifcvf_set_vq_num(struct ifcvf_hw *hw, u16 qid, u32 num);
>>> +void ifcvf_set_vq_ready(struct ifcvf_hw *hw, u16 qid, bool ready);
>>> +bool ifcvf_get_vq_ready(struct ifcvf_hw *hw, u16 qid);
>>> #endif /* _IFCVF_H_ */
>>> diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
>>> index 4366320fb68d..e442aa11333e 100644
>>> --- a/drivers/vdpa/ifcvf/ifcvf_main.c
>>> +++ b/drivers/vdpa/ifcvf/ifcvf_main.c
>>> @@ -374,37 +374,6 @@ static int ifcvf_start_datapath(void *private)
>>> return ret;
>>> }
>>>
>>> -static int ifcvf_stop_datapath(void *private)
>>> -{
>>> - struct ifcvf_hw *vf = ifcvf_private_to_vf(private);
>>> - int i;
>>> -
>>> - for (i = 0; i < vf->nr_vring; i++)
>>> - vf->vring[i].cb.callback = NULL;
>>> -
>>> - ifcvf_stop_hw(vf);
>>> -
>>> - return 0;
>>> -}
>>> -
>>> -static void ifcvf_reset_vring(struct ifcvf_adapter *adapter)
>>> -{
>>> - struct ifcvf_hw *vf = ifcvf_private_to_vf(adapter);
>>> - int i;
>>> -
>>> - for (i = 0; i < vf->nr_vring; i++) {
>>> - vf->vring[i].last_avail_idx = 0;
>>> - vf->vring[i].desc = 0;
>>> - vf->vring[i].avail = 0;
>>> - vf->vring[i].used = 0;
>>> - vf->vring[i].ready = 0;
>>> - vf->vring[i].cb.callback = NULL;
>>> - vf->vring[i].cb.private = NULL;
>>> - }
>>> -
>>> - ifcvf_reset(vf);
>>> -}
>>> -
>>> static struct ifcvf_adapter *vdpa_to_adapter(struct vdpa_device *vdpa_dev)
>>> {
>>> return container_of(vdpa_dev, struct ifcvf_adapter, vdpa);
>>> @@ -477,6 +446,8 @@ static void ifcvf_vdpa_set_status(struct vdpa_device *vdpa_dev, u8 status)
>>> if (status_old == status)
>>> return;
>>>
>>> + ifcvf_set_status(vf, status);
>>> +
>>> if ((status & VIRTIO_CONFIG_S_DRIVER_OK) &&
>>> !(status_old & VIRTIO_CONFIG_S_DRIVER_OK)) {
>>> ret = ifcvf_request_irq(adapter);
>> Does this mean e.g for DRIVER_OK the device may work before the
>> interrupt handler is requested?
>>
>> Looks racy.
>>
>> Thanks
>>
>>> @@ -493,7 +464,6 @@ static void ifcvf_vdpa_set_status(struct vdpa_device *vdpa_dev, u8 status)
>>> status);
>>> }
>>>
>>> - ifcvf_set_status(vf, status);
>>> }
>>>
>>> static int ifcvf_vdpa_reset(struct vdpa_device *vdpa_dev)
>>> @@ -509,12 +479,10 @@ static int ifcvf_vdpa_reset(struct vdpa_device *vdpa_dev)
>>> if (status_old == 0)
>>> return 0;
>>>
>>> - if (status_old & VIRTIO_CONFIG_S_DRIVER_OK) {
>>> - ifcvf_stop_datapath(adapter);
>>> - ifcvf_free_irq(adapter);
>>> - }
>>> + ifcvf_stop_hw(vf);
>>> + ifcvf_free_irq(adapter);
>>>
>>> - ifcvf_reset_vring(adapter);
>>> + ifcvf_reset(vf);
>>>
>>> return 0;
>>> }
>>> @@ -554,14 +522,17 @@ static void ifcvf_vdpa_set_vq_ready(struct vdpa_device *vdpa_dev,
>>> {
>>> struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
>>>
>>> - vf->vring[qid].ready = ready;
>>> + ifcvf_set_vq_ready(vf, qid, ready);
>>> }
>>>
>>> static bool ifcvf_vdpa_get_vq_ready(struct vdpa_device *vdpa_dev, u16 qid)
>>> {
>>> struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
>>> + bool ready;
>>>
>>> - return vf->vring[qid].ready;
>>> + ready = ifcvf_get_vq_ready(vf, qid);
>>> +
>>> + return ready;
>>> }
>>>
>>> static void ifcvf_vdpa_set_vq_num(struct vdpa_device *vdpa_dev, u16 qid,
>>> @@ -569,7 +540,7 @@ static void ifcvf_vdpa_set_vq_num(struct vdpa_device *vdpa_dev, u16 qid,
>>> {
>>> struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
>>>
>>> - vf->vring[qid].size = num;
>>> + ifcvf_set_vq_num(vf, qid, num);
>>> }
>>>
>>> static int ifcvf_vdpa_set_vq_address(struct vdpa_device *vdpa_dev, u16 qid,
>>> @@ -578,11 +549,7 @@ static int ifcvf_vdpa_set_vq_address(struct vdpa_device *vdpa_dev, u16 qid,
>>> {
>>> struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
>>>
>>> - vf->vring[qid].desc = desc_area;
>>> - vf->vring[qid].avail = driver_area;
>>> - vf->vring[qid].used = device_area;
>>> -
>>> - return 0;
>>> + return ifcvf_set_vq_address(vf, qid, desc_area, driver_area, device_area);
>>> }
>>>
>>> static void ifcvf_vdpa_kick_vq(struct vdpa_device *vdpa_dev, u16 qid)
>>> --
>>> 2.31.1
>>>
Powered by blists - more mailing lists