[PATCH v7 19/24] iommu/arm-smmu-v3: Maintain a SID->device structure

Jean-Philippe Brucker
2020-05-19T18:08:42Z

When handling faults from the event or PRI queue, we need to find the
struct device associated to a SID. Add a rb_tree to keep track of SIDs.

Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
---
drivers/iommu/arm-smmu-v3.c | 175 +++++++++++++++++++++++++++++-------
1 file changed, 145 insertions(+), 30 deletions(-)

diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index 6a368218f54c..70dfbd2817aa 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -701,6 +701,15 @@ struct arm_smmu_device {

/* IOMMU core code handle */
struct iommu_device iommu;
+
+ struct rb_root streams;
+ struct mutex streams_mutex;
+};
+
+struct arm_smmu_stream {
+ u32 id;
+ struct arm_smmu_master *master;
+ struct rb_node node;
};

/* SMMU private data for each master */
@@ -709,8 +718,8 @@ struct arm_smmu_master {
struct device *dev;
struct arm_smmu_domain *domain;
struct list_head domain_head;
- u32 *sids;
- unsigned int num_sids;
+ struct arm_smmu_stream *streams;
+ unsigned int num_streams;
bool ats_enabled;
bool sva_enabled;
struct list_head bonds;
@@ -1622,8 +1631,8 @@ static void arm_smmu_sync_cd(struct arm_smmu_domain *smmu_domain,

spin_lock_irqsave(&smmu_domain->devices_lock, flags);
list_for_each_entry(master, &smmu_domain->devices, domain_head) {
- for (i = 0; i < master->num_sids; i++) {
- cmd.cfgi.sid = master->sids[i];
+ for (i = 0; i < master->num_streams; i++) {
+ cmd.cfgi.sid = master->streams[i].id;
arm_smmu_cmdq_batch_add(smmu, &cmds, &cmd);
}
}
@@ -2239,6 +2248,32 @@ static int arm_smmu_init_l2_strtab(struct arm_smmu_device *smmu, u32 sid)
return 0;
}

+__maybe_unused
+static struct arm_smmu_master *
+arm_smmu_find_master(struct arm_smmu_device *smmu, u32 sid)
+{
+ struct rb_node *node;
+ struct arm_smmu_stream *stream;
+ struct arm_smmu_master *master = NULL;
+
+ mutex_lock(&smmu->streams_mutex);
+ node = smmu->streams.rb_node;
+ while (node) {
+ stream = rb_entry(node, struct arm_smmu_stream, node);
+ if (stream->id < sid) {
+ node = node->rb_right;
+ } else if (stream->id > sid) {
+ node = node->rb_left;
+ } else {
+ master = stream->master;
+ break;
+ }
+ }
+ mutex_unlock(&smmu->streams_mutex);
+
+ return master;
+}
+
/* IRQ and event handlers */
static irqreturn_t arm_smmu_evtq_thread(int irq, void *dev)
{
@@ -2472,8 +2507,8 @@ static int arm_smmu_atc_inv_master(struct arm_smmu_master *master, int ssid)

arm_smmu_atc_inv_to_cmd(ssid, 0, 0, &cmd);

- for (i = 0; i < master->num_sids; i++) {
- cmd.atc.sid = master->sids[i];
+ for (i = 0; i < master->num_streams; i++) {
+ cmd.atc.sid = master->streams[i].id;
arm_smmu_cmdq_issue_cmd(master->smmu, &cmd);
}

@@ -2516,8 +2551,8 @@ static int arm_smmu_atc_inv_domain(struct arm_smmu_domain *smmu_domain,
if (!master->ats_enabled)
continue;

- for (i = 0; i < master->num_sids; i++) {
- cmd.atc.sid = master->sids[i];
+ for (i = 0; i < master->num_streams; i++) {
+ cmd.atc.sid = master->streams[i].id;
arm_smmu_cmdq_batch_add(smmu_domain->smmu, &cmds, &cmd);
}
}
@@ -2940,13 +2975,13 @@ static void arm_smmu_install_ste_for_dev(struct arm_smmu_master *master)
int i, j;
struct arm_smmu_device *smmu = master->smmu;

- for (i = 0; i < master->num_sids; ++i) {
- u32 sid = master->sids[i];
+ for (i = 0; i < master->num_streams; ++i) {
+ u32 sid = master->streams[i].id;
__le64 *step = arm_smmu_get_step_for_sid(smmu, sid);

/* Bridged PCI devices may end up with duplicated IDs */
for (j = 0; j < i; j++)
- if (master->sids[j] == sid)
+ if (master->streams[j].id == sid)
break;
if (j < i)
continue;
@@ -3429,11 +3464,101 @@ static bool arm_smmu_sid_in_range(struct arm_smmu_device *smmu, u32 sid)
return sid < limit;
}

+static int arm_smmu_insert_master(struct arm_smmu_device *smmu,
+ struct arm_smmu_master *master)
+{
+ int i;
+ int ret = 0;
+ struct arm_smmu_stream *new_stream, *cur_stream;
+ struct rb_node **new_node, *parent_node = NULL;
+ struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(master->dev);
+
+ master->streams = kcalloc(fwspec->num_ids,
+ sizeof(struct arm_smmu_stream), GFP_KERNEL);
+ if (!master->streams)
+ return -ENOMEM;
+ master->num_streams = fwspec->num_ids;
+
+ mutex_lock(&smmu->streams_mutex);
+ for (i = 0; i < fwspec->num_ids && !ret; i++) {
+ u32 sid = fwspec->ids[i];
+
+ new_stream = &master->streams[i];
+ new_stream->id = sid;
+ new_stream->master = master;
+
+ /*
+ * Check the SIDs are in range of the SMMU and our stream table
+ */
+ if (!arm_smmu_sid_in_range(smmu, sid)) {
+ ret = -ERANGE;
+ break;
+ }
+
+ /* Ensure l2 strtab is initialised */
+ if (smmu->features & ARM_SMMU_FEAT_2_LVL_STRTAB) {
+ ret = arm_smmu_init_l2_strtab(smmu, sid);
+ if (ret)
+ break;
+ }
+
+ /* Insert into SID tree */
+ new_node = &(smmu->streams.rb_node);
+ while (*new_node) {
+ cur_stream = rb_entry(*new_node, struct arm_smmu_stream,
+ node);
+ parent_node = *new_node;
+ if (cur_stream->id > new_stream->id) {
+ new_node = &((*new_node)->rb_left);
+ } else if (cur_stream->id < new_stream->id) {
+ new_node = &((*new_node)->rb_right);
+ } else {
+ dev_warn(master->dev,
+ "stream %u already in tree\n",
+ cur_stream->id);
+ ret = -EINVAL;
+ break;
+ }
+ }
+
+ if (!ret) {
+ rb_link_node(&new_stream->node, parent_node, new_node);
+ rb_insert_color(&new_stream->node, &smmu->streams);
+ }
+ }
+
+ if (ret) {
+ for (; i > 0; i--)
+ rb_erase(&master->streams[i].node, &smmu->streams);
+ kfree(master->streams);
+ }
+ mutex_unlock(&smmu->streams_mutex);
+
+ return ret;
+}
+
+static void arm_smmu_remove_master(struct arm_smmu_device *smmu,
+ struct arm_smmu_master *master)
+{
+ int i;
+ struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(master->dev);
+
+ if (!master->streams)
+ return;
+
+ mutex_lock(&smmu->streams_mutex);
+ for (i = 0; i < fwspec->num_ids; i++)
+ rb_erase(&master->streams[i].node, &smmu->streams);
+ mutex_unlock(&smmu->streams_mutex);
+
+ kfree(master->streams);
+}
+
static struct iommu_ops arm_smmu_ops;

static int arm_smmu_add_device(struct device *dev)
{
- int i, ret;
+ int ret;
struct arm_smmu_device *smmu;
struct arm_smmu_master *master;
struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev);
@@ -3455,27 +3580,12 @@ static int arm_smmu_add_device(struct device *dev)

master->dev = dev;
master->smmu = smmu;
- master->sids = fwspec->ids;
- master->num_sids = fwspec->num_ids;
INIT_LIST_HEAD(&master->bonds);
dev_iommu_priv_set(dev, master);

- /* Check the SIDs are in range of the SMMU and our stream table */
- for (i = 0; i < master->num_sids; i++) {
- u32 sid = master->sids[i];
-
- if (!arm_smmu_sid_in_range(smmu, sid)) {
- ret = -ERANGE;
- goto err_free_master;
- }
-
- /* Ensure l2 strtab is initialised */
- if (smmu->features & ARM_SMMU_FEAT_2_LVL_STRTAB) {
- ret = arm_smmu_init_l2_strtab(smmu, sid);
- if (ret)
- goto err_free_master;
- }
- }
+ ret = arm_smmu_insert_master(smmu, master);
+ if (ret)
+ goto err_free_master;

master->ssid_bits = min(smmu->ssid_bits, fwspec->num_pasid_bits);

@@ -3510,6 +3620,7 @@ static int arm_smmu_add_device(struct device *dev)
iommu_device_unlink(&smmu->iommu, dev);
err_disable_pasid:
arm_smmu_disable_pasid(master);
+ arm_smmu_remove_master(smmu, master);
err_free_master:
kfree(master);
dev_iommu_priv_set(dev, NULL);
@@ -3532,6 +3643,7 @@ static void arm_smmu_remove_device(struct device *dev)
iommu_group_remove_device(dev);
iommu_device_unlink(&smmu->iommu, dev);
arm_smmu_disable_pasid(master);
+ arm_smmu_remove_master(smmu, master);
kfree(master);
iommu_fwspec_free(dev);
}
@@ -3994,6 +4106,9 @@ static int arm_smmu_init_structures(struct arm_smmu_device *smmu)
{
int ret;

+ mutex_init(&smmu->streams_mutex);
+ smmu->streams = RB_ROOT;
+
ret = arm_smmu_init_queues(smmu);
if (ret)
return ret;