On Tue, Aug 23, 2016 at 08:05:22PM +0100, Robin Murphy wrote: > To be able to support the generic bindings and handle of_xlate() calls, > we need to be able to associate SMMUs and stream IDs directly with > devices *before* allocating IOMMU groups. Furthermore, to support real > default domains with multi-device groups we also have to handle domain > attach on a per-device basis, as the "whole group at a time" assumption > fails to properly handle subsequent devices added to a group after the > first has already triggered default domain creation and attachment. > > To that end, use the now-vacant dev->archdata.iommu field for easy > config and SMMU instance lookup, and unify config management by chopping > down the platform-device-specific tree and probing the "mmu-masters" > property on-demand instead. This may add a bit of one-off overhead to > initially adding a new device, but we're about to deprecate that binding > in favour of the inherently-more-efficient generic ones anyway. > > For the sake of simplicity, this patch does temporarily regress the case > of aliasing PCI devices by losing the duplicate stream ID detection that > the previous per-group config had. Stay tuned, because we'll be back to > fix that in a better and more general way momentarily... > > Signed-off-by: Robin Murphy <[email protected]> > --- > drivers/iommu/arm-smmu.c | 382 > +++++++++++++---------------------------------- > 1 file changed, 107 insertions(+), 275 deletions(-) > > diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c > index 22c093030322..9066fd1399d4 100644 > --- a/drivers/iommu/arm-smmu.c > +++ b/drivers/iommu/arm-smmu.c > @@ -317,18 +317,13 @@ struct arm_smmu_smr { > }; > > struct arm_smmu_master_cfg { > + struct arm_smmu_device *smmu; > int num_streamids; > u16 streamids[MAX_MASTER_STREAMIDS]; > s16 smendx[MAX_MASTER_STREAMIDS]; > }; > #define INVALID_SMENDX -1 > > -struct arm_smmu_master { > - struct device_node *of_node; > - struct rb_node node; > - struct arm_smmu_master_cfg cfg; > -}; > - > struct arm_smmu_device { > struct device *dev; > > @@ -376,7 +371,6 @@ struct arm_smmu_device { > unsigned int *irqs; > > struct list_head list; > - struct rb_root masters; > > u32 cavium_id_base; /* Specific to Cavium */ > }; > @@ -415,12 +409,6 @@ struct arm_smmu_domain { > struct iommu_domain domain; > }; > > -struct arm_smmu_phandle_args { > - struct device_node *np; > - int args_count; > - uint32_t args[MAX_MASTER_STREAMIDS]; > -}; > - > static DEFINE_SPINLOCK(arm_smmu_devices_lock); > static LIST_HEAD(arm_smmu_devices); > > @@ -462,132 +450,89 @@ static struct device_node *dev_get_dev_node(struct > device *dev) > > while (!pci_is_root_bus(bus)) > bus = bus->parent; > - return bus->bridge->parent->of_node; > + return of_node_get(bus->bridge->parent->of_node); > } > > - return dev->of_node; > + return of_node_get(dev->of_node); > } > > -static struct arm_smmu_master *find_smmu_master(struct arm_smmu_device *smmu, > - struct device_node *dev_node) > +static int __arm_smmu_get_pci_sid(struct pci_dev *pdev, u16 alias, void > *data) > { > - struct rb_node *node = smmu->masters.rb_node; > - > - while (node) { > - struct arm_smmu_master *master; > - > - master = container_of(node, struct arm_smmu_master, node); > - > - if (dev_node < master->of_node) > - node = node->rb_left; > - else if (dev_node > master->of_node) > - node = node->rb_right; > - else > - return master; > - } > - > - return NULL; > + *((__be32 *)data) = cpu_to_be32(alias); > + return 0; /* Continue walking */ > } > > -static struct arm_smmu_master_cfg * > -find_smmu_master_cfg(struct device *dev) > +static int __find_legacy_master_phandle(struct device *dev, void *data) > { > - struct arm_smmu_master_cfg *cfg = NULL; > - struct iommu_group *group = iommu_group_get(dev); > + struct of_phandle_iterator *it = *(void **)data; > + struct device_node *np = it->node; > + int err; > > - if (group) { > - cfg = iommu_group_get_iommudata(group); > - iommu_group_put(group); > - } > - > - return cfg; > -} > - > -static int insert_smmu_master(struct arm_smmu_device *smmu, > - struct arm_smmu_master *master) > -{ > - struct rb_node **new, *parent; > - > - new = &smmu->masters.rb_node; > - parent = NULL; > - while (*new) { > - struct arm_smmu_master *this > - = container_of(*new, struct arm_smmu_master, node); > - > - parent = *new; > - if (master->of_node < this->of_node) > - new = &((*new)->rb_left); > - else if (master->of_node > this->of_node) > - new = &((*new)->rb_right); > - else > - return -EEXIST; > - } > - > - rb_link_node(&master->node, parent, new); > - rb_insert_color(&master->node, &smmu->masters); > - return 0; > -} > - > -static int register_smmu_master(struct arm_smmu_device *smmu, > - struct device *dev, > - struct arm_smmu_phandle_args *masterspec) > -{ > - int i; > - struct arm_smmu_master *master; > - > - master = find_smmu_master(smmu, masterspec->np); > - if (master) { > - dev_err(dev, > - "rejecting multiple registrations for master device > %s\n", > - masterspec->np->name); > - return -EBUSY; > - } > - > - if (masterspec->args_count > MAX_MASTER_STREAMIDS) { > - dev_err(dev, > - "reached maximum number (%d) of stream IDs for master > device %s\n", > - MAX_MASTER_STREAMIDS, masterspec->np->name); > - return -ENOSPC; > - } > - > - master = devm_kzalloc(dev, sizeof(*master), GFP_KERNEL); > - if (!master) > - return -ENOMEM; > - > - master->of_node = masterspec->np; > - master->cfg.num_streamids = masterspec->args_count; > - > - for (i = 0; i < master->cfg.num_streamids; ++i) { > - u16 streamid = masterspec->args[i]; > - > - if (!(smmu->features & ARM_SMMU_FEAT_STREAM_MATCH) && > - (streamid >= smmu->num_mapping_groups)) { > - dev_err(dev, > - "stream ID for master device %s greater than > maximum allowed (%d)\n", > - masterspec->np->name, smmu->num_mapping_groups); > - return -ERANGE; > + of_for_each_phandle(it, err, dev->of_node, "mmu-masters", > + "#stream-id-cells", 0) > + if (it->node == np) { > + *(void **)data = dev; > + return 1; > } > - master->cfg.streamids[i] = streamid; > - master->cfg.smendx[i] = INVALID_SMENDX; > - } > - return insert_smmu_master(smmu, master); > + it->node = np; > + return err; > } > > -static struct arm_smmu_device *find_smmu_for_device(struct device *dev) > +static int arm_smmu_register_legacy_master(struct device *dev) > { > struct arm_smmu_device *smmu; > - struct arm_smmu_master *master = NULL; > - struct device_node *dev_node = dev_get_dev_node(dev); > + struct arm_smmu_master_cfg *cfg; > + struct device_node *np; > + struct of_phandle_iterator it; > + void *data = ⁢ > + __be32 pci_sid; > + int err; > > + np = dev_get_dev_node(dev); > + if (!np || !of_find_property(np, "#stream-id-cells", NULL)) { > + of_node_put(np); > + return -ENODEV; > + } > + > + it.node = np; > spin_lock(&arm_smmu_devices_lock); > list_for_each_entry(smmu, &arm_smmu_devices, list) { > - master = find_smmu_master(smmu, dev_node); > - if (master) > + err = __find_legacy_master_phandle(smmu->dev, &data); > + if (err) > break; > } > spin_unlock(&arm_smmu_devices_lock); > + of_node_put(np); > + if (err == 0) > + return -ENODEV; > + if (err < 0) > + return err; > > - return master ? smmu : NULL; > + if (it.cur_count > MAX_MASTER_STREAMIDS) { > + dev_err(smmu->dev, > + "reached maximum number (%d) of stream IDs for master > device %s\n", > + MAX_MASTER_STREAMIDS, dev_name(dev)); > + return -ENOSPC; > + } > + if (dev_is_pci(dev)) { > + /* "mmu-masters" assumes Stream ID == Requester ID */ > + pci_for_each_dma_alias(to_pci_dev(dev), __arm_smmu_get_pci_sid, > + &pci_sid); > + it.cur = &pci_sid; > + it.cur_count = 1; > + } > + > + cfg = kzalloc(sizeof(*cfg), GFP_KERNEL); > + if (!cfg) > + return -ENOMEM; > + > + cfg->smmu = smmu; > + dev->archdata.iommu = cfg; > + > + while (it.cur_count--) > + cfg->streamids[cfg->num_streamids++] = be32_to_cpup(it.cur++);
I pronounce this construct, the "Murphy Device"! At least it didn't survive until the end of the series :p Will _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
