iommu/arm-smmu-v3: Prepare for handling arm_smmu_write_ctx_desc() failure

Second-level context descriptor tables will be allocated lazily in
arm_smmu_write_ctx_desc(). Help with handling allocation failure by
moving the CD write into arm_smmu_domain_finalise_s1().

Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
[will: Add comment per discussion on list]
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index 88a4825..a224b91 100644 (file)
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -2279,8 +2279,20 @@ static int arm_smmu_domain_finalise_s1(struct arm_smmu_domain *smmu_domain,
                          FIELD_PREP(CTXDESC_CD_0_TCR_IPS, tcr->ips) |
                          CTXDESC_CD_0_TCR_EPD1 | CTXDESC_CD_0_AA64;
        cfg->cd.mair    = pgtbl_cfg->arm_lpae_s1_cfg.mair;
+
+       /*
+        * Note that this will end up calling arm_smmu_sync_cd() before
+        * the master has been added to the devices list for this domain.
+        * This isn't an issue because the STE hasn't been installed yet.
+        */
+       ret = arm_smmu_write_ctx_desc(smmu_domain, 0, &cfg->cd);
+       if (ret)
+               goto out_free_cd_tables;
+
        return 0;
 
+out_free_cd_tables:
+       arm_smmu_free_cd_tables(smmu_domain);
 out_free_asid:
        arm_smmu_bitmap_free(smmu->asid_map, asid);
        return ret;
@@ -2555,10 +2567,6 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
        if (smmu_domain->stage != ARM_SMMU_DOMAIN_BYPASS)
                master->ats_enabled = arm_smmu_ats_supported(master);
 
-       if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1)
-               arm_smmu_write_ctx_desc(smmu_domain, 0,
-                                       &smmu_domain->s1_cfg.cd);
-
        arm_smmu_install_ste_for_dev(master);
 
        spin_lock_irqsave(&smmu_domain->devices_lock, flags);