[PATCH v12 04/15] iommu/smmuv3: Dynamically allocate s1_cfg and s2_cfg

From: Eric Auger
Date: Mon Nov 16 2020 - 05:44:16 EST


In preparation for the introduction of nested stages
let's turn s1_cfg and s2_cfg fields into pointers which are
dynamically allocated depending on the smmu_domain stage.

In nested mode, both stages will coexist and s1_cfg will
be allocated when the guest configuration gets passed.

Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx>
---
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 83 ++++++++++++---------
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 6 +-
2 files changed, 48 insertions(+), 41 deletions(-)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index d828d6cbeb0e..4baf9fafe462 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -953,9 +953,9 @@ static __le64 *arm_smmu_get_cd_ptr(struct arm_smmu_domain *smmu_domain,
unsigned int idx;
struct arm_smmu_l1_ctx_desc *l1_desc;
struct arm_smmu_device *smmu = smmu_domain->smmu;
- struct arm_smmu_ctx_desc_cfg *cdcfg = &smmu_domain->s1_cfg.cdcfg;
+ struct arm_smmu_ctx_desc_cfg *cdcfg = &smmu_domain->s1_cfg->cdcfg;

- if (smmu_domain->s1_cfg.s1fmt == STRTAB_STE_0_S1FMT_LINEAR)
+ if (smmu_domain->s1_cfg->s1fmt == STRTAB_STE_0_S1FMT_LINEAR)
return cdcfg->cdtab + ssid * CTXDESC_CD_DWORDS;

idx = ssid >> CTXDESC_SPLIT;
@@ -990,7 +990,7 @@ int arm_smmu_write_ctx_desc(struct arm_smmu_domain *smmu_domain, int ssid,
__le64 *cdptr;
struct arm_smmu_device *smmu = smmu_domain->smmu;

- if (WARN_ON(ssid >= (1 << smmu_domain->s1_cfg.s1cdmax)))
+ if (WARN_ON(ssid >= (1 << smmu_domain->s1_cfg->s1cdmax)))
return -E2BIG;

cdptr = arm_smmu_get_cd_ptr(smmu_domain, ssid);
@@ -1056,7 +1056,7 @@ static int arm_smmu_alloc_cd_tables(struct arm_smmu_domain *smmu_domain)
size_t l1size;
size_t max_contexts;
struct arm_smmu_device *smmu = smmu_domain->smmu;
- struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg;
+ struct arm_smmu_s1_cfg *cfg = smmu_domain->s1_cfg;
struct arm_smmu_ctx_desc_cfg *cdcfg = &cfg->cdcfg;

max_contexts = 1 << cfg->s1cdmax;
@@ -1104,7 +1104,7 @@ static void arm_smmu_free_cd_tables(struct arm_smmu_domain *smmu_domain)
int i;
size_t size, l1size;
struct arm_smmu_device *smmu = smmu_domain->smmu;
- struct arm_smmu_ctx_desc_cfg *cdcfg = &smmu_domain->s1_cfg.cdcfg;
+ struct arm_smmu_ctx_desc_cfg *cdcfg = &smmu_domain->s1_cfg->cdcfg;

if (cdcfg->l1_desc) {
size = CTXDESC_L2_ENTRIES * (CTXDESC_CD_DWORDS << 3);
@@ -1211,17 +1211,8 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid,
}

if (smmu_domain) {
- switch (smmu_domain->stage) {
- case ARM_SMMU_DOMAIN_S1:
- s1_cfg = &smmu_domain->s1_cfg;
- break;
- case ARM_SMMU_DOMAIN_S2:
- case ARM_SMMU_DOMAIN_NESTED:
- s2_cfg = &smmu_domain->s2_cfg;
- break;
- default:
- break;
- }
+ s1_cfg = smmu_domain->s1_cfg;
+ s2_cfg = smmu_domain->s2_cfg;
}

if (val & STRTAB_STE_0_V) {
@@ -1664,10 +1655,10 @@ static void arm_smmu_tlb_inv_context(void *cookie)
* careful, 007.
*/
if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
- arm_smmu_tlb_inv_asid(smmu, smmu_domain->s1_cfg.cd.asid);
+ arm_smmu_tlb_inv_asid(smmu, smmu_domain->s1_cfg->cd.asid);
} else {
cmd.opcode = CMDQ_OP_TLBI_S12_VMALL;
- cmd.tlbi.vmid = smmu_domain->s2_cfg.vmid;
+ cmd.tlbi.vmid = smmu_domain->s2_cfg->vmid;
arm_smmu_cmdq_issue_cmd(smmu, &cmd);
arm_smmu_cmdq_issue_sync(smmu);
}
@@ -1693,10 +1684,10 @@ static void arm_smmu_tlb_inv_range(unsigned long iova, size_t size,

if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
cmd.opcode = CMDQ_OP_TLBI_NH_VA;
- cmd.tlbi.asid = smmu_domain->s1_cfg.cd.asid;
+ cmd.tlbi.asid = smmu_domain->s1_cfg->cd.asid;
} else {
cmd.opcode = CMDQ_OP_TLBI_S2_IPA;
- cmd.tlbi.vmid = smmu_domain->s2_cfg.vmid;
+ cmd.tlbi.vmid = smmu_domain->s2_cfg->vmid;
}

if (smmu->features & ARM_SMMU_FEAT_RANGE_INV) {
@@ -1846,24 +1837,25 @@ static void arm_smmu_domain_free(struct iommu_domain *domain)
{
struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
struct arm_smmu_device *smmu = smmu_domain->smmu;
+ struct arm_smmu_s1_cfg *s1_cfg = smmu_domain->s1_cfg;
+ struct arm_smmu_s2_cfg *s2_cfg = smmu_domain->s2_cfg;

iommu_put_dma_cookie(domain);
free_io_pgtable_ops(smmu_domain->pgtbl_ops);

/* Free the CD and ASID, if we allocated them */
- if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
- struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg;
-
- /* Prevent SVA from touching the CD while we're freeing it */
+ if (s1_cfg) {
mutex_lock(&arm_smmu_asid_lock);
- if (cfg->cdcfg.cdtab)
+ /* Prevent SVA from touching the CD while we're freeing it */
+ if (s1_cfg->cdcfg.cdtab)
arm_smmu_free_cd_tables(smmu_domain);
- arm_smmu_free_asid(&cfg->cd);
+ arm_smmu_free_asid(&s1_cfg->cd);
mutex_unlock(&arm_smmu_asid_lock);
- } else {
- struct arm_smmu_s2_cfg *cfg = &smmu_domain->s2_cfg;
- if (cfg->vmid)
- arm_smmu_bitmap_free(smmu->vmid_map, cfg->vmid);
+ }
+ if (s2_cfg) {
+ if (s2_cfg->vmid)
+ arm_smmu_bitmap_free(smmu->vmid_map, s2_cfg->vmid);
+ kfree(s2_cfg);
}

kfree(smmu_domain);
@@ -1876,8 +1868,11 @@ static int arm_smmu_domain_finalise_s1(struct arm_smmu_domain *smmu_domain,
int ret;
u32 asid;
struct arm_smmu_device *smmu = smmu_domain->smmu;
- struct arm_smmu_s1_cfg *cfg = &smmu_domain->s1_cfg;
typeof(&pgtbl_cfg->arm_lpae_s1_cfg.tcr) tcr = &pgtbl_cfg->arm_lpae_s1_cfg.tcr;
+ struct arm_smmu_s1_cfg *cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
+
+ if (!cfg)
+ return -ENOMEM;

refcount_set(&cfg->cd.refs, 1);

@@ -1890,6 +1885,8 @@ static int arm_smmu_domain_finalise_s1(struct arm_smmu_domain *smmu_domain,

cfg->s1cdmax = master->ssid_bits;

+ smmu_domain->s1_cfg = cfg;
+
ret = arm_smmu_alloc_cd_tables(smmu_domain);
if (ret)
goto out_free_asid;
@@ -1922,6 +1919,8 @@ static int arm_smmu_domain_finalise_s1(struct arm_smmu_domain *smmu_domain,
out_free_asid:
arm_smmu_free_asid(&cfg->cd);
out_unlock:
+ kfree(cfg);
+ smmu_domain->s1_cfg = NULL;
mutex_unlock(&arm_smmu_asid_lock);
return ret;
}
@@ -1930,14 +1929,19 @@ static int arm_smmu_domain_finalise_s2(struct arm_smmu_domain *smmu_domain,
struct arm_smmu_master *master,
struct io_pgtable_cfg *pgtbl_cfg)
{
- int vmid;
+ int vmid, ret;
struct arm_smmu_device *smmu = smmu_domain->smmu;
- struct arm_smmu_s2_cfg *cfg = &smmu_domain->s2_cfg;
+ struct arm_smmu_s2_cfg *cfg = kzalloc(sizeof(*cfg), GFP_KERNEL);
typeof(&pgtbl_cfg->arm_lpae_s2_cfg.vtcr) vtcr;

+ if (!cfg)
+ return -ENOMEM;
+
vmid = arm_smmu_bitmap_alloc(smmu->vmid_map, smmu->vmid_bits);
- if (vmid < 0)
- return vmid;
+ if (vmid < 0) {
+ ret = vmid;
+ goto out_free_cfg;
+ }

vtcr = &pgtbl_cfg->arm_lpae_s2_cfg.vtcr;
cfg->vmid = (u16)vmid;
@@ -1949,7 +1953,12 @@ static int arm_smmu_domain_finalise_s2(struct arm_smmu_domain *smmu_domain,
FIELD_PREP(STRTAB_STE_2_VTCR_S2SH0, vtcr->sh) |
FIELD_PREP(STRTAB_STE_2_VTCR_S2TG, vtcr->tg) |
FIELD_PREP(STRTAB_STE_2_VTCR_S2PS, vtcr->ps);
+ smmu_domain->s2_cfg = cfg;
return 0;
+
+out_free_cfg:
+ kfree(cfg);
+ return ret;
}

static int arm_smmu_domain_finalise(struct iommu_domain *domain,
@@ -2231,10 +2240,10 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
ret = -ENXIO;
goto out_unlock;
} else if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1 &&
- master->ssid_bits != smmu_domain->s1_cfg.s1cdmax) {
+ master->ssid_bits != smmu_domain->s1_cfg->s1cdmax) {
dev_err(dev,
"cannot attach to incompatible domain (%u SSID bits != %u)\n",
- smmu_domain->s1_cfg.s1cdmax, master->ssid_bits);
+ smmu_domain->s1_cfg->s1cdmax, master->ssid_bits);
ret = -EINVAL;
goto out_unlock;
}
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
index 2944beb1571b..6fdc35b32dbf 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -679,10 +679,8 @@ struct arm_smmu_domain {
atomic_t nr_ats_masters;

enum arm_smmu_domain_stage stage;
- union {
- struct arm_smmu_s1_cfg s1_cfg;
- struct arm_smmu_s2_cfg s2_cfg;
- };
+ struct arm_smmu_s1_cfg *s1_cfg;
+ struct arm_smmu_s2_cfg *s2_cfg;

struct iommu_domain domain;

--
2.21.3