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Enable stage-2 in case the host puts an STE in bypass or stage-1. Signed-off-by: Mostafa Saleh --- .../iommu/arm/arm-smmu-v3/pkvm/arm-smmu-v3.c | 109 ++++++++++++++++-- 1 file changed, 102 insertions(+), 7 deletions(-) diff --git a/drivers/iommu/arm/arm-smmu-v3/pkvm/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/pkvm/arm-smmu-v3.c index f30757dd9b11..4625240a5de2 100644 --- a/drivers/iommu/arm/arm-smmu-v3/pkvm/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/pkvm/arm-smmu-v3.c @@ -380,6 +380,59 @@ static int smmu_init_cmdq(struct hyp_arm_smmu_v3_device *smmu) return 0; } +static int smmu_attach_stage_2(struct arm_smmu_ste *ste) +{ + unsigned long vttbr; + unsigned long ts, sl, ic, oc, sh, tg, ps; + unsigned long cfg; + struct io_pgtable_cfg *pgt_cfg = &idmap_pgtable->cfg; + + cfg = FIELD_GET(STRTAB_STE_0_CFG, le64_to_cpu(ste->data[0])); + if (!FIELD_GET(STRTAB_STE_0_V, le64_to_cpu(ste->data[0])) || + (cfg == STRTAB_STE_0_CFG_ABORT)) { + ste->data[2] = 0; + ste->data[3] = 0; + return 0; + } + /* S2 is not advertised, that should never be attempted. */ + if (cfg == STRTAB_STE_0_CFG_NESTED) + return -EINVAL; + vttbr = pgt_cfg->arm_lpae_s2_cfg.vttbr; + ps = pgt_cfg->arm_lpae_s2_cfg.vtcr.ps; + tg = pgt_cfg->arm_lpae_s2_cfg.vtcr.tg; + sh = pgt_cfg->arm_lpae_s2_cfg.vtcr.sh; + oc = pgt_cfg->arm_lpae_s2_cfg.vtcr.orgn; + ic = pgt_cfg->arm_lpae_s2_cfg.vtcr.irgn; + sl = pgt_cfg->arm_lpae_s2_cfg.vtcr.sl; + ts = pgt_cfg->arm_lpae_s2_cfg.vtcr.tsz; + + ste->data[1] &= ~cpu_to_le64(STRTAB_STE_1_SHCFG); + ste->data[1] |= cpu_to_le64(FIELD_PREP(STRTAB_STE_1_SHCFG, STRTAB_STE_1_SHCFG_INCOMING)); + + ste->data[1] &= ~cpu_to_le64(STRTAB_STE_1_EATS | STRTAB_STE_1_S2FWB); + + /* The host shouldn't write dwords 2 and 3, overwrite them. */ + ste->data[2] = cpu_to_le64(FIELD_PREP(STRTAB_STE_2_VTCR, + FIELD_PREP(STRTAB_STE_2_VTCR_S2PS, ps) | + FIELD_PREP(STRTAB_STE_2_VTCR_S2TG, tg) | + FIELD_PREP(STRTAB_STE_2_VTCR_S2SH0, sh) | + FIELD_PREP(STRTAB_STE_2_VTCR_S2OR0, oc) | + FIELD_PREP(STRTAB_STE_2_VTCR_S2IR0, ic) | + FIELD_PREP(STRTAB_STE_2_VTCR_S2SL0, sl) | + FIELD_PREP(STRTAB_STE_2_VTCR_S2T0SZ, ts)) | + FIELD_PREP(STRTAB_STE_2_S2VMID, 0) | + STRTAB_STE_2_S2AA64 | STRTAB_STE_2_S2R | + #ifdef __BIG_ENDIAN + STRTAB_STE_2_S2ENDI | +#endif + STRTAB_STE_2_S2PTW); + + ste->data[3] = cpu_to_le64(vttbr & STRTAB_STE_3_S2TTB_MASK); + /* Convert S1 => nested and bypass => S2 */ + ste->data[0] |= cpu_to_le64(FIELD_PREP(STRTAB_STE_0_CFG, cfg | BIT(1))); + return 0; +} + static int smmu_get_host_l2_ste(struct hyp_arm_smmu_v3_device *smmu, u32 sid, struct arm_smmu_ste *host_ste_out) { @@ -412,8 +465,12 @@ static int smmu_get_host_l2_ste(struct hyp_arm_smmu_v3_device *smmu, u32 sid, static int smmu_reshadow_ste(struct hyp_arm_smmu_v3_device *smmu, u32 sid, bool leaf) { struct arm_smmu_strtab_cfg *cfg = &smmu->strtab_cfg; - struct arm_smmu_ste *hyp_ste_ptr, *host_ste_ptr, host_ste_copy; + struct arm_smmu_ste *hyp_ste_ptr; u64 *hyp_ste_base = strtab_hyp_base(smmu); + struct arm_smmu_ste target = {}; + struct arm_smmu_cmd cfgi_cmd = arm_smmu_make_cmd_cfgi_ste(sid, true); + bool cur_valid, target_valid; + u32 target_cfg; int ret, i; /* @@ -435,7 +492,7 @@ static int smmu_reshadow_ste(struct hyp_arm_smmu_v3_device *smmu, u32 sid, bool return -E2BIG; hyp_ste_ptr = &hyp_table[sid]; - host_ste_ptr = &host_table[sid]; + memcpy(target.data, host_table[sid].data, STRTAB_STE_DWORDS << 3); } else { struct arm_smmu_strtab_l1 *l1tab = (struct arm_smmu_strtab_l1 *)hyp_ste_base; u32 l1_idx = arm_smmu_strtab_l1_idx(sid); @@ -444,8 +501,7 @@ static int smmu_reshadow_ste(struct hyp_arm_smmu_v3_device *smmu, u32 sid, bool if (l1_idx >= cfg->l2.num_l1_ents) return -E2BIG; - host_ste_ptr = &host_ste_copy; - ret = smmu_get_host_l2_ste(smmu, sid, host_ste_ptr); + ret = smmu_get_host_l2_ste(smmu, sid, &target); if (ret) return ret; @@ -463,9 +519,48 @@ static int smmu_reshadow_ste(struct hyp_arm_smmu_v3_device *smmu, u32 sid, bool hyp_ste_ptr = &l2ptr->stes[arm_smmu_strtab_l2_idx(sid)]; } - for (i = 0 ; i < STRTAB_STE_DWORDS ; ++i) - WRITE_ONCE(hyp_ste_ptr->data[i], host_ste_ptr->data[i]); - return 0; + /* + * Summary of each host emulated state vs real HW. + * | Host | HW | + * ============================== + * | V=0 | V=0 | + * | Abort | Abort | + * | Bypass | S2 | + * | S1 | S1+S2 | + * + * For the host, any V=0 transition is not hitless, all other permutations of + * (abort, bypass, S1) transitions are hitless. + * For the HW state, any V=0 transition is not hitless, as all the S2 config is + * always the same (ttbr, vtcr...), all other transitions should be hitless too. + * However, the host is not trusted, which means that any V=0 <=> V=1 transitions + * or any transition to an abort STE we need to enforce writing order of the STE + * dword 0 and add CFGI. + * Otherwise, we write the STE in the opposite order to cover cases from abort + * to S2 or nested. + */ + ret = smmu_attach_stage_2(&target); + if (ret) + return ret; + hyp_spin_lock(&smmu->hw_lock); + cur_valid = FIELD_GET(STRTAB_STE_0_V, le64_to_cpu(hyp_ste_ptr->data[0])); + target_cfg = FIELD_GET(STRTAB_STE_0_CFG, le64_to_cpu(target.data[0])); + target_valid = FIELD_GET(STRTAB_STE_0_V, le64_to_cpu(target.data[0])); + if ((cur_valid && !target_valid) || + (target_cfg == STRTAB_STE_0_CFG_ABORT)) { + WRITE_ONCE(hyp_ste_ptr->data[0], target.data[0]); + WARN_ON(smmu_send_cmd(smmu, &cfgi_cmd)); + for (i = 1; i < STRTAB_STE_DWORDS; i++) + WRITE_ONCE(hyp_ste_ptr->data[i], target.data[i]); + } else { + for (i = 1; i < STRTAB_STE_DWORDS; i++) + WRITE_ONCE(hyp_ste_ptr->data[i], target.data[i]); + WARN_ON(smmu_send_cmd(smmu, &cfgi_cmd)); + WRITE_ONCE(hyp_ste_ptr->data[0], target.data[0]); + } + + ret = smmu_send_cmd(smmu, &cfgi_cmd); + hyp_spin_unlock(&smmu->hw_lock); + return ret; } static int smmu_init_strtab(struct hyp_arm_smmu_v3_device *smmu) -- 2.55.0.141.g00534a21ce-goog