Hi Eric,
On 2020/11/18 19:21, Eric Auger wrote:
> From: Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx>
>
> When handling faults from the event or PRI queue, we need to find the
> struct device associated to a SID. Add a rb_tree to keep track of SIDs.
>
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx>
[...]
> }
>
> +static int arm_smmu_insert_master(struct arm_smmu_device *smmu,
> + struct arm_smmu_master *master)
> +{
> + int i;
> + int ret = 0;
> + struct arm_smmu_stream *new_stream, *cur_stream;
> + struct rb_node **new_node, *parent_node = NULL;
> + struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(master->dev);
> +
> + master->streams = kcalloc(fwspec->num_ids,
> + sizeof(struct arm_smmu_stream), GFP_KERNEL);
> + if (!master->streams)
> + return -ENOMEM;
> + master->num_streams = fwspec->num_ids;
This is not roll-backed when fail.
> +
> + mutex_lock(&smmu->streams_mutex);
> + for (i = 0; i < fwspec->num_ids && !ret; i++) {
Check ret at here, makes it hard to decide the start index of rollback.
If we fail at here, then start index is (i-2).
If we fail in the loop, then start index is (i-1).
> + u32 sid = fwspec->ids[i];
> +
> + new_stream = &master->streams[i];
> + new_stream->id = sid;
> + new_stream->master = master;
> +
> + /*
> + * Check the SIDs are in range of the SMMU and our stream table
> + */
> + if (!arm_smmu_sid_in_range(smmu, sid)) {
> + ret = -ERANGE;
> + break;
> + }
> +
> + /* Ensure l2 strtab is initialised */
> + if (smmu->features & ARM_SMMU_FEAT_2_LVL_STRTAB) {
> + ret = arm_smmu_init_l2_strtab(smmu, sid);
> + if (ret)
> + break;
> + }
> +
> + /* Insert into SID tree */
> + new_node = &(smmu->streams.rb_node);
> + while (*new_node) {
> + cur_stream = rb_entry(*new_node, struct arm_smmu_stream,
> + node);
> + parent_node = *new_node;
> + if (cur_stream->id > new_stream->id) {
> + new_node = &((*new_node)->rb_left);
> + } else if (cur_stream->id < new_stream->id) {
> + new_node = &((*new_node)->rb_right);
> + } else {
> + dev_warn(master->dev,
> + "stream %u already in tree\n",
> + cur_stream->id);
> + ret = -EINVAL;
> + break;
> + }
> + }
> +
> + if (!ret) {
> + rb_link_node(&new_stream->node, parent_node, new_node);
> + rb_insert_color(&new_stream->node, &smmu->streams);
> + }
> + }
> +
> + if (ret) {
> + for (; i > 0; i--)
should be (i >= 0)?
And the start index seems not correct.
> + rb_erase(&master->streams[i].node, &smmu->streams);
> + kfree(master->streams);
> + }
> + mutex_unlock(&smmu->streams_mutex);
> +
> + return ret;
> +}
> +
> +static void arm_smmu_remove_master(struct arm_smmu_master *master)
> +{
> + int i;
> + struct arm_smmu_device *smmu = master->smmu;
> + struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(master->dev);
> +
> + if (!smmu || !master->streams)
> + return;
> +
> + mutex_lock(&smmu->streams_mutex);
> + for (i = 0; i < fwspec->num_ids; i++)
> + rb_erase(&master->streams[i].node, &smmu->streams);
> + mutex_unlock(&smmu->streams_mutex);
> +
> + kfree(master->streams);
> +}
> +
> static struct iommu_ops arm_smmu_ops;
>
> static struct iommu_device *arm_smmu_probe_device(struct device *dev)
> {
> - int i, ret;
> + int ret;
> struct arm_smmu_device *smmu;
> struct arm_smmu_master *master;
> struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
> @@ -2331,27 +2447,12 @@ static struct iommu_device *arm_smmu_probe_device(struct device *dev)
>
> master->dev = dev;
> master->smmu = smmu;
> - master->sids = fwspec->ids;
> - master->num_sids = fwspec->num_ids;
> INIT_LIST_HEAD(&master->bonds);
> dev_iommu_priv_set(dev, master);
>
> - /* Check the SIDs are in range of the SMMU and our stream table */
> - for (i = 0; i < master->num_sids; i++) {
> - u32 sid = master->sids[i];
> -
> - if (!arm_smmu_sid_in_range(smmu, sid)) {
> - ret = -ERANGE;
> - goto err_free_master;
> - }
> -
> - /* Ensure l2 strtab is initialised */
> - if (smmu->features & ARM_SMMU_FEAT_2_LVL_STRTAB) {
> - ret = arm_smmu_init_l2_strtab(smmu, sid);
> - if (ret)
> - goto err_free_master;
> - }
> - }
> + ret = arm_smmu_insert_master(smmu, master);
> + if (ret)
> + goto err_free_master;
>
> master->ssid_bits = min(smmu->ssid_bits, fwspec->num_pasid_bits);
>
> @@ -2389,6 +2490,7 @@ static void arm_smmu_release_device(struct device *dev)
> WARN_ON(arm_smmu_master_sva_enabled(master));
> arm_smmu_detach_dev(master);
> arm_smmu_disable_pasid(master);
> + arm_smmu_remove_master(master);
> kfree(master);
Thanks,
Keqian
