On 24/03/2026 00:51, Milan Djokic wrote:
> From: Jean-Philippe Brucker <jean-philippe@linaro.org>
>
> Backport Linux commit cdf315f907d4. This is the clean backport without
> any changes.
>
> When handling faults from the event or PRI queue, we need to find the
> struct device associated with a SID. Add a rb_tree to keep track of
> SIDs.
>
> Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Reviewed-by: Eric Auger <eric.auger@redhat.com>
> Reviewed-by: Keqian Zhu <zhukeqian1@huawei.com>
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
> Acked-by: Will Deacon <will@kernel.org>
> Link: https://lore.kernel.org/r/20210401154718.307519-8-jean-philippe@linaro.org
> Signed-off-by: Joerg Roedel <jroedel@suse.de>
> Origin: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git cdf315f907d4
> Signed-off-by: Rahul Singh <rahul.singh@arm.com>
Your Signed-off-by is missing:
Signed-off-by: Milan Djokic <milan_djokic@epam.com>
> ---
> xen/drivers/passthrough/arm/smmu-v3.c | 131 +++++++++++++++++++++-----
> xen/drivers/passthrough/arm/smmu-v3.h | 13 ++-
> 2 files changed, 118 insertions(+), 26 deletions(-)
>
> diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
> index bf153227db..73cc4ef08f 100644
> --- a/xen/drivers/passthrough/arm/smmu-v3.c
> +++ b/xen/drivers/passthrough/arm/smmu-v3.c
> @@ -809,6 +809,27 @@ static int arm_smmu_init_l2_strtab(struct arm_smmu_device *smmu, u32 sid)
> return 0;
> }
>
> +__maybe_unused
> +static struct arm_smmu_master *
> +arm_smmu_find_master(struct arm_smmu_device *smmu, u32 sid)
> +{
> + struct rb_node *node;
> + struct arm_smmu_stream *stream;
> +
> + node = smmu->streams.rb_node;
> + while (node) {
> + stream = rb_entry(node, struct arm_smmu_stream, node);
> + if (stream->id < sid)
> + node = node->rb_right;
> + else if (stream->id > sid)
> + node = node->rb_left;
> + else
> + return stream->master;
> + }
> +
> + return NULL;
> +}
> +
> /* IRQ and event handlers */
> static void arm_smmu_evtq_tasklet(void *dev)
> {
> @@ -1042,8 +1063,8 @@ static int arm_smmu_atc_inv_master(struct arm_smmu_master *master,
> if (!master->ats_enabled)
> return 0;
>
> - for (i = 0; i < master->num_sids; i++) {
> - cmd->atc.sid = master->sids[i];
> + for (i = 0; i < master->num_streams; i++) {
> + cmd->atc.sid = master->streams[i].id;
> arm_smmu_cmdq_issue_cmd(master->smmu, cmd);
> }
>
> @@ -1271,13 +1292,13 @@ static void arm_smmu_install_ste_for_dev(struct arm_smmu_master *master)
> int i, j;
> struct arm_smmu_device *smmu = master->smmu;
>
> - for (i = 0; i < master->num_sids; ++i) {
> - u32 sid = master->sids[i];
> + for (i = 0; i < master->num_streams; ++i) {
> + u32 sid = master->streams[i].id;
> __le64 *step = arm_smmu_get_step_for_sid(smmu, sid);
>
> /* Bridged PCI devices may end up with duplicated IDs */
> for (j = 0; j < i; j++)
> - if (master->sids[j] == sid)
> + if (master->streams[j].id == sid)
> break;
> if (j < i)
> continue;
> @@ -1486,6 +1507,80 @@ static bool arm_smmu_sid_in_range(struct arm_smmu_device *smmu, u32 sid)
>
> return sid < limit;
> }
> +
> +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 = _xzalloc_array(sizeof(*master->streams), sizeof(void *),
> + fwspec->num_ids);
> + if (!master->streams)
> + return -ENOMEM;
> + master->num_streams = fwspec->num_ids;
> +
> + mutex_lock(&smmu->streams_mutex);
> + for (i = 0; i < fwspec->num_ids; i++) {
> + 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)
> + break;
> +
> + rb_link_node(&new_stream->node, parent_node, new_node);
> + rb_insert_color(&new_stream->node, &smmu->streams);
> + }
> +
> + if (ret) {
> + for (i--; i >= 0; i--)
> + rb_erase(&master->streams[i].node, &smmu->streams);
> + xfree(master->streams);
> + }
> + mutex_unlock(&smmu->streams_mutex);
> +
> + return ret;
> +}
> +
> /* Forward declaration */
> static struct arm_smmu_device *arm_smmu_get_by_dev(const struct device *dev);
> static int arm_smmu_assign_dev(struct domain *d, u8 devfn, struct device *dev,
> @@ -1495,7 +1590,7 @@ static int arm_smmu_deassign_dev(struct domain *d, uint8_t devfn,
>
> static int arm_smmu_add_device(u8 devfn, struct device *dev)
> {
> - int i, ret;
> + int ret;
> struct arm_smmu_device *smmu;
> struct arm_smmu_master *master;
> struct iommu_fwspec *fwspec;
> @@ -1532,26 +1627,11 @@ static int arm_smmu_add_device(u8 devfn, struct device *dev)
>
> master->dev = dev;
> master->smmu = smmu;
> - master->sids = fwspec->ids;
> - master->num_sids = fwspec->num_ids;
> 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;
>
> /*
> * Note that PASID must be enabled before, and disabled after ATS:
> @@ -1796,6 +1876,9 @@ static int __init arm_smmu_init_structures(struct arm_smmu_device *smmu)
> {
> int ret;
>
> + mutex_init(&smmu->streams_mutex);
> + smmu->streams = RB_ROOT;
> +
> ret = arm_smmu_init_queues(smmu);
> if (ret)
> return ret;
> diff --git a/xen/drivers/passthrough/arm/smmu-v3.h b/xen/drivers/passthrough/arm/smmu-v3.h
> index ab07366294..ab1f29f6c7 100644
> --- a/xen/drivers/passthrough/arm/smmu-v3.h
> +++ b/xen/drivers/passthrough/arm/smmu-v3.h
> @@ -639,6 +639,15 @@ struct arm_smmu_device {
> struct tasklet evtq_irq_tasklet;
> struct tasklet priq_irq_tasklet;
> struct tasklet combined_irq_tasklet;
> +
> + struct rb_root streams;
> + struct mutex streams_mutex;
> +};
> +
> +struct arm_smmu_stream {
> + u32 id;
> + struct arm_smmu_master *master;
> + struct rb_node node;
> };
>
> /* SMMU private data for each master */
> @@ -647,8 +656,8 @@ struct arm_smmu_master {
> struct device *dev;
> struct arm_smmu_domain *domain;
> struct list_head domain_head;
> - u32 *sids;
> - unsigned int num_sids;
> + struct arm_smmu_stream *streams;
> + unsigned int num_streams;
> bool ats_enabled;
> };
>