On Sat, Mar 28, 2026 at 06:17:04PM +0800, Qinxin Xia wrote:
> +static int smmu_debugfs_ste_show(struct seq_file *seq, void *unused)
> +{
> + struct ste_context *ctx = seq->private;
> + struct arm_smmu_master *master = ctx->master;
> + struct arm_smmu_device *smmu;
> + struct arm_smmu_ste *ste;
> + u32 sid, cfg;
> + int i;
> +
> + if (!master) {
> + seq_puts(seq, "No SMMU master data\n");
> + return 0;
> + }
> +
> + smmu = master->smmu;
> + scoped_guard(mutex, &smmu->streams_mutex) {
Instead:
guard(mutex)(&smmu->streams_mutex);
> + sid = ctx->sid;
> +
> + if (!arm_smmu_sid_in_range(smmu, sid)) {
> + seq_printf(seq, "Invalid Stream ID: %u (max %u)\n",
> + sid, (1 << smmu->sid_bits) - 1);
> + return 0;
> + }
> +
> + ste = arm_smmu_get_step_for_sid(smmu, sid);
> + if (!ste) {
> + seq_printf(seq, "STE not available for SID %u\n", sid);
> + return 0;
> + }
> +
> + seq_printf(seq, "STE for Stream ID %u\n", sid);
> + seq_printf(seq, " Valid: %s\n",
> + le64_to_cpu(ste->data[0]) & STRTAB_STE_0_V ? "Yes" : "No");
> +
> + seq_puts(seq, " Config: ");
> +
> + cfg = FIELD_GET(STRTAB_STE_0_CFG, le64_to_cpu(ste->data[0]));
> +
> + switch (cfg) {
> + case STRTAB_STE_0_CFG_BYPASS:
> + seq_puts(seq, "BYPASS\n");
> + break;
> + case STRTAB_STE_0_CFG_S1_TRANS:
> + seq_puts(seq, "only S1_TRANS\n");
> + break;
> + case STRTAB_STE_0_CFG_S2_TRANS:
> + seq_puts(seq, "only S2_TRANS\n");
> + break;
> + case STRTAB_STE_0_CFG_NESTED:
> + seq_puts(seq, "S1+S2_TRANS\n");
> + break;
> + case STRTAB_STE_0_CFG_ABORT:
> + seq_puts(seq, "ABORT\n");
> + break;
> + default:
> + seq_puts(seq, "UNKNOWN\n");
> + }
> +
> + if (le64_to_cpu(ste->data[0]) & STRTAB_STE_0_CFG_S1_TRANS) {
> + seq_printf(seq, " S1ContextPtr: 0x%016llx\n",
> + le64_to_cpu(ste->data[1]) & STRTAB_STE_0_S1CTXPTR_MASK);
> + }
> +
> + if (le64_to_cpu(ste->data[0]) & STRTAB_STE_0_CFG_S2_TRANS) {
> + seq_printf(seq, " S2ContextPtr: 0x%016llx\n",
> + le64_to_cpu(ste->data[3]) & STRTAB_STE_3_S2TTB_MASK);
> + }
> +
> + /* Display raw STE data */
> + seq_puts(seq, " Raw Data:\n");
> + for (i = 0; i < STRTAB_STE_DWORDS; i++)
> + seq_printf(seq, " STE[%d]: 0x%016llx\n", i,
> + le64_to_cpu(ste->data[i]));
> + }
> + return 0;
Check the indentation of the return line.
> +/**
> + * arm_smmu_debugfs_create_stream_table() - Create debugfs entries for stream table
> + * @dev: device to create entries for
> + * @smmu: SMMU device
> + *
> + * Return: 0 on success, negative error code on failure
> + */
> +int arm_smmu_debugfs_create_stream_table(struct device *dev,
> + struct arm_smmu_device *smmu)
Usually @smmu would be the first parameter.
> +{
> + struct dentry *stream_dir, *dev_dir;
> + struct arm_smmu_master *master;
> + struct ste_context *ctx;
> + char name[64];
> + u32 sid;
> + int i;
> +
> + scoped_guard(mutex, &arm_smmu_debugfs_lock) {
> + if (!smmu->debugfs->stream_dir) {
> + stream_dir = debugfs_create_dir("stream_table",
> + smmu->debugfs->smmu_dir);
> + if (!stream_dir)
> + return -ENOMEM;
> +
> + smmu->debugfs->stream_dir = stream_dir;
> + } else {
> + stream_dir = smmu->debugfs->stream_dir;
> + }
> + }
> +
> + master = dev_iommu_priv_get(dev);
> + if (!master || !master->num_streams)
> + return -ENODEV;
> +
> + for (i = 0; i < master->num_streams; i++) {
> + sid = master->streams[i].id;
> + snprintf(name, sizeof(name), "%u", sid);
> + dev_dir = debugfs_create_dir(name, stream_dir);
> + if (!dev_dir)
> + continue;
> +
> + /* Create STE file */
> + ctx = kzalloc_obj(*ctx);
> + ctx->master = master;
> + ctx->sid = sid;
> + spin_lock(&smmu->debugfs->stream_lock);
> + list_add_tail(&ctx->node, &smmu->debugfs->stream_list);
> + spin_unlock(&smmu->debugfs->stream_lock);
May consider an RCU list instead of locking.
> +/**
> + * arm_smmu_debugfs_remove_stream_table() - Remove debugfs entries for stream table
> + * @dev: device to remove entries for
> + * @smmu: SMMU device
Again, @smmu could be the first parameter.
> + * This function removes the debugfs directories created by
> + * arm_smmu_debugfs_create_stream_table().
> + */
> +void arm_smmu_debugfs_remove_stream_table(struct device *dev,
> + struct arm_smmu_device *smmu)
Please double check the indentation. It looks odd on my side.
> -static struct arm_smmu_ste *
> +#ifndef CONFIG_ARM_SMMU_V3_DEBUGFS
> +static
> +#endif
> +struct arm_smmu_ste *
> arm_smmu_get_step_for_sid(struct arm_smmu_device *smmu, u32 sid)
Could probably move this to the header.
> -static bool arm_smmu_sid_in_range(struct arm_smmu_device *smmu, u32 sid)
> +#ifndef CONFIG_ARM_SMMU_V3_DEBUGFS
> +static
> +#endif
> +bool arm_smmu_sid_in_range(struct arm_smmu_device *smmu, u32 sid)
Ditto
> @@ -3648,10 +3658,14 @@ static void arm_smmu_release_device(struct device *dev)
>
> WARN_ON(master->iopf_refcount);
>
> +#ifdef CONFIG_ARM_SMMU_V3_DEBUGFS
> + arm_smmu_debugfs_remove_stream_table(dev, master->smmu);
> +#endif
> arm_smmu_disable_pasid(master);
> arm_smmu_remove_master(master);
> if (arm_smmu_cdtab_allocated(&master->cd_table))
> arm_smmu_free_cd_tables(master);
> +
> kfree(master);
Meaningless line.
> struct arm_smmu_debugfs {
> + struct list_head stream_list;
> + spinlock_t stream_lock;
> struct dentry *smmu_dir;
> + struct dentry *stream_dir;
> /* Reserved for future extensions */
> };
That's the end of the struct. What do you reserve?
Nicolin