From: Jean-Philippe Brucker <jean-philippe@linaro.org>
Date: Wed, 15 Jan 2020 13:52:35 +0100
Subject: iommu/arm-smmu-v3: Prepare for handling arm_smmu_write_ctx_desc()
 failure
Git-commit: 492ddc79e07ed16a4ec4b6f57787273b2e4c26c1
References: bsc#1175713
Patch-mainline: v5.6-rc1

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>
Acked-by: Joerg Roedel <jroedel@suse.de>
---
 drivers/iommu/arm-smmu-v3.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index 88a48256c11e..a224b915fc59 100644
--- 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);