diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-07-24 16:24:11 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-07-24 16:24:11 -0700 |
commit | 97027da6adf2e24a4e8d3d9c0668da3006b29971 (patch) | |
tree | 7da3aa43a9e8c9be0a408b814e6f0d3106c55d66 /drivers/iommu/iommu.c | |
parent | 6dd53aa4563a2c69e80a24d2cc68d484b5ea2891 (diff) | |
parent | 395e51f18d3b26619c1c462b7a1c0226846ac0a9 (diff) |
Merge tag 'iommu-updates-v3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU updates from Joerg Roedel:
"The most important part of these updates is the IOMMU groups code
enhancement written by Alex Williamson. It abstracts the problem that
a given hardware IOMMU can't isolate any given device from any other
device (e.g. 32 bit PCI devices can't usually be isolated). Devices
that can't be isolated are grouped together. This code is required
for the upcoming VFIO framework.
Another IOMMU-API change written by me is the introduction of domain
attributes. This makes it easier to handle GART-like IOMMUs with the
IOMMU-API because now the start-address and the size of the domain
address space can be queried.
Besides that there are a few cleanups and fixes for the NVidia Tegra
IOMMU drivers and the reworked init-code for the AMD IOMMU. The
latter is from my patch-set to support interrupt remapping. The rest
of this patch-set requires x86 changes which are not mergabe yet. So
full support for interrupt remapping with AMD IOMMUs will come in a
future merge window."
* tag 'iommu-updates-v3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (33 commits)
iommu/amd: Fix hotplug with iommu=pt
iommu/amd: Add missing spin_lock initialization
iommu/amd: Convert iommu initialization to state machine
iommu/amd: Introduce amd_iommu_init_dma routine
iommu/amd: Move unmap_flush message to amd_iommu_init_dma_ops()
iommu/amd: Split enable_iommus() routine
iommu/amd: Introduce early_amd_iommu_init routine
iommu/amd: Move informational prinks out of iommu_enable
iommu/amd: Split out PCI related parts of IOMMU initialization
iommu/amd: Use acpi_get_table instead of acpi_table_parse
iommu/amd: Fix sparse warnings
iommu/tegra: Don't call alloc_pdir with as->lock
iommu/tegra: smmu: Fix unsleepable memory allocation at alloc_pdir()
iommu/tegra: smmu: Remove unnecessary sanity check at alloc_pdir()
iommu/exynos: Implement DOMAIN_ATTR_GEOMETRY attribute
iommu/tegra: Implement DOMAIN_ATTR_GEOMETRY attribute
iommu/msm: Implement DOMAIN_ATTR_GEOMETRY attribute
iommu/omap: Implement DOMAIN_ATTR_GEOMETRY attribute
iommu/vt-d: Implement DOMAIN_ATTR_GEOMETRY attribute
iommu/amd: Implement DOMAIN_ATTR_GEOMETRY attribute
...
Diffstat (limited to 'drivers/iommu/iommu.c')
-rw-r--r-- | drivers/iommu/iommu.c | 611 |
1 files changed, 581 insertions, 30 deletions
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 8b9ded88e6f5..ddbdacad7768 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -26,60 +26,535 @@ #include <linux/slab.h> #include <linux/errno.h> #include <linux/iommu.h> +#include <linux/idr.h> +#include <linux/notifier.h> +#include <linux/err.h> + +static struct kset *iommu_group_kset; +static struct ida iommu_group_ida; +static struct mutex iommu_group_mutex; + +struct iommu_group { + struct kobject kobj; + struct kobject *devices_kobj; + struct list_head devices; + struct mutex mutex; + struct blocking_notifier_head notifier; + void *iommu_data; + void (*iommu_data_release)(void *iommu_data); + char *name; + int id; +}; + +struct iommu_device { + struct list_head list; + struct device *dev; + char *name; +}; + +struct iommu_group_attribute { + struct attribute attr; + ssize_t (*show)(struct iommu_group *group, char *buf); + ssize_t (*store)(struct iommu_group *group, + const char *buf, size_t count); +}; + +#define IOMMU_GROUP_ATTR(_name, _mode, _show, _store) \ +struct iommu_group_attribute iommu_group_attr_##_name = \ + __ATTR(_name, _mode, _show, _store) + +#define to_iommu_group_attr(_attr) \ + container_of(_attr, struct iommu_group_attribute, attr) +#define to_iommu_group(_kobj) \ + container_of(_kobj, struct iommu_group, kobj) -static ssize_t show_iommu_group(struct device *dev, - struct device_attribute *attr, char *buf) +static ssize_t iommu_group_attr_show(struct kobject *kobj, + struct attribute *__attr, char *buf) { - unsigned int groupid; + struct iommu_group_attribute *attr = to_iommu_group_attr(__attr); + struct iommu_group *group = to_iommu_group(kobj); + ssize_t ret = -EIO; - if (iommu_device_group(dev, &groupid)) - return 0; + if (attr->show) + ret = attr->show(group, buf); + return ret; +} + +static ssize_t iommu_group_attr_store(struct kobject *kobj, + struct attribute *__attr, + const char *buf, size_t count) +{ + struct iommu_group_attribute *attr = to_iommu_group_attr(__attr); + struct iommu_group *group = to_iommu_group(kobj); + ssize_t ret = -EIO; + + if (attr->store) + ret = attr->store(group, buf, count); + return ret; +} + +static const struct sysfs_ops iommu_group_sysfs_ops = { + .show = iommu_group_attr_show, + .store = iommu_group_attr_store, +}; - return sprintf(buf, "%u", groupid); +static int iommu_group_create_file(struct iommu_group *group, + struct iommu_group_attribute *attr) +{ + return sysfs_create_file(&group->kobj, &attr->attr); } -static DEVICE_ATTR(iommu_group, S_IRUGO, show_iommu_group, NULL); -static int add_iommu_group(struct device *dev, void *data) +static void iommu_group_remove_file(struct iommu_group *group, + struct iommu_group_attribute *attr) +{ + sysfs_remove_file(&group->kobj, &attr->attr); +} + +static ssize_t iommu_group_show_name(struct iommu_group *group, char *buf) +{ + return sprintf(buf, "%s\n", group->name); +} + +static IOMMU_GROUP_ATTR(name, S_IRUGO, iommu_group_show_name, NULL); + +static void iommu_group_release(struct kobject *kobj) +{ + struct iommu_group *group = to_iommu_group(kobj); + + if (group->iommu_data_release) + group->iommu_data_release(group->iommu_data); + + mutex_lock(&iommu_group_mutex); + ida_remove(&iommu_group_ida, group->id); + mutex_unlock(&iommu_group_mutex); + + kfree(group->name); + kfree(group); +} + +static struct kobj_type iommu_group_ktype = { + .sysfs_ops = &iommu_group_sysfs_ops, + .release = iommu_group_release, +}; + +/** + * iommu_group_alloc - Allocate a new group + * @name: Optional name to associate with group, visible in sysfs + * + * This function is called by an iommu driver to allocate a new iommu + * group. The iommu group represents the minimum granularity of the iommu. + * Upon successful return, the caller holds a reference to the supplied + * group in order to hold the group until devices are added. Use + * iommu_group_put() to release this extra reference count, allowing the + * group to be automatically reclaimed once it has no devices or external + * references. + */ +struct iommu_group *iommu_group_alloc(void) +{ + struct iommu_group *group; + int ret; + + group = kzalloc(sizeof(*group), GFP_KERNEL); + if (!group) + return ERR_PTR(-ENOMEM); + + group->kobj.kset = iommu_group_kset; + mutex_init(&group->mutex); + INIT_LIST_HEAD(&group->devices); + BLOCKING_INIT_NOTIFIER_HEAD(&group->notifier); + + mutex_lock(&iommu_group_mutex); + +again: + if (unlikely(0 == ida_pre_get(&iommu_group_ida, GFP_KERNEL))) { + kfree(group); + mutex_unlock(&iommu_group_mutex); + return ERR_PTR(-ENOMEM); + } + + if (-EAGAIN == ida_get_new(&iommu_group_ida, &group->id)) + goto again; + + mutex_unlock(&iommu_group_mutex); + + ret = kobject_init_and_add(&group->kobj, &iommu_group_ktype, + NULL, "%d", group->id); + if (ret) { + mutex_lock(&iommu_group_mutex); + ida_remove(&iommu_group_ida, group->id); + mutex_unlock(&iommu_group_mutex); + kfree(group); + return ERR_PTR(ret); + } + + group->devices_kobj = kobject_create_and_add("devices", &group->kobj); + if (!group->devices_kobj) { + kobject_put(&group->kobj); /* triggers .release & free */ + return ERR_PTR(-ENOMEM); + } + + /* + * The devices_kobj holds a reference on the group kobject, so + * as long as that exists so will the group. We can therefore + * use the devices_kobj for reference counting. + */ + kobject_put(&group->kobj); + + return group; +} +EXPORT_SYMBOL_GPL(iommu_group_alloc); + +/** + * iommu_group_get_iommudata - retrieve iommu_data registered for a group + * @group: the group + * + * iommu drivers can store data in the group for use when doing iommu + * operations. This function provides a way to retrieve it. Caller + * should hold a group reference. + */ +void *iommu_group_get_iommudata(struct iommu_group *group) +{ + return group->iommu_data; +} +EXPORT_SYMBOL_GPL(iommu_group_get_iommudata); + +/** + * iommu_group_set_iommudata - set iommu_data for a group + * @group: the group + * @iommu_data: new data + * @release: release function for iommu_data + * + * iommu drivers can store data in the group for use when doing iommu + * operations. This function provides a way to set the data after + * the group has been allocated. Caller should hold a group reference. + */ +void iommu_group_set_iommudata(struct iommu_group *group, void *iommu_data, + void (*release)(void *iommu_data)) { - unsigned int groupid; + group->iommu_data = iommu_data; + group->iommu_data_release = release; +} +EXPORT_SYMBOL_GPL(iommu_group_set_iommudata); - if (iommu_device_group(dev, &groupid) == 0) - return device_create_file(dev, &dev_attr_iommu_group); +/** + * iommu_group_set_name - set name for a group + * @group: the group + * @name: name + * + * Allow iommu driver to set a name for a group. When set it will + * appear in a name attribute file under the group in sysfs. + */ +int iommu_group_set_name(struct iommu_group *group, const char *name) +{ + int ret; + + if (group->name) { + iommu_group_remove_file(group, &iommu_group_attr_name); + kfree(group->name); + group->name = NULL; + if (!name) + return 0; + } + + group->name = kstrdup(name, GFP_KERNEL); + if (!group->name) + return -ENOMEM; + + ret = iommu_group_create_file(group, &iommu_group_attr_name); + if (ret) { + kfree(group->name); + group->name = NULL; + return ret; + } return 0; } +EXPORT_SYMBOL_GPL(iommu_group_set_name); + +/** + * iommu_group_add_device - add a device to an iommu group + * @group: the group into which to add the device (reference should be held) + * @dev: the device + * + * This function is called by an iommu driver to add a device into a + * group. Adding a device increments the group reference count. + */ +int iommu_group_add_device(struct iommu_group *group, struct device *dev) +{ + int ret, i = 0; + struct iommu_device *device; + + device = kzalloc(sizeof(*device), GFP_KERNEL); + if (!device) + return -ENOMEM; + + device->dev = dev; + + ret = sysfs_create_link(&dev->kobj, &group->kobj, "iommu_group"); + if (ret) { + kfree(device); + return ret; + } + + device->name = kasprintf(GFP_KERNEL, "%s", kobject_name(&dev->kobj)); +rename: + if (!device->name) { + sysfs_remove_link(&dev->kobj, "iommu_group"); + kfree(device); + return -ENOMEM; + } + + ret = sysfs_create_link_nowarn(group->devices_kobj, + &dev->kobj, device->name); + if (ret) { + kfree(device->name); + if (ret == -EEXIST && i >= 0) { + /* + * Account for the slim chance of collision + * and append an instance to the name. + */ + device->name = kasprintf(GFP_KERNEL, "%s.%d", + kobject_name(&dev->kobj), i++); + goto rename; + } + + sysfs_remove_link(&dev->kobj, "iommu_group"); + kfree(device); + return ret; + } + + kobject_get(group->devices_kobj); + + dev->iommu_group = group; + + mutex_lock(&group->mutex); + list_add_tail(&device->list, &group->devices); + mutex_unlock(&group->mutex); + + /* Notify any listeners about change to group. */ + blocking_notifier_call_chain(&group->notifier, + IOMMU_GROUP_NOTIFY_ADD_DEVICE, dev); + return 0; +} +EXPORT_SYMBOL_GPL(iommu_group_add_device); + +/** + * iommu_group_remove_device - remove a device from it's current group + * @dev: device to be removed + * + * This function is called by an iommu driver to remove the device from + * it's current group. This decrements the iommu group reference count. + */ +void iommu_group_remove_device(struct device *dev) +{ + struct iommu_group *group = dev->iommu_group; + struct iommu_device *tmp_device, *device = NULL; + + /* Pre-notify listeners that a device is being removed. */ + blocking_notifier_call_chain(&group->notifier, + IOMMU_GROUP_NOTIFY_DEL_DEVICE, dev); + + mutex_lock(&group->mutex); + list_for_each_entry(tmp_device, &group->devices, list) { + if (tmp_device->dev == dev) { + device = tmp_device; + list_del(&device->list); + break; + } + } + mutex_unlock(&group->mutex); + + if (!device) + return; + + sysfs_remove_link(group->devices_kobj, device->name); + sysfs_remove_link(&dev->kobj, "iommu_group"); + + kfree(device->name); + kfree(device); + dev->iommu_group = NULL; + kobject_put(group->devices_kobj); +} +EXPORT_SYMBOL_GPL(iommu_group_remove_device); + +/** + * iommu_group_for_each_dev - iterate over each device in the group + * @group: the group + * @data: caller opaque data to be passed to callback function + * @fn: caller supplied callback function + * + * This function is called by group users to iterate over group devices. + * Callers should hold a reference count to the group during callback. + * The group->mutex is held across callbacks, which will block calls to + * iommu_group_add/remove_device. + */ +int iommu_group_for_each_dev(struct iommu_group *group, void *data, + int (*fn)(struct device *, void *)) +{ + struct iommu_device *device; + int ret = 0; + + mutex_lock(&group->mutex); + list_for_each_entry(device, &group->devices, list) { + ret = fn(device->dev, data); + if (ret) + break; + } + mutex_unlock(&group->mutex); + return ret; +} +EXPORT_SYMBOL_GPL(iommu_group_for_each_dev); + +/** + * iommu_group_get - Return the group for a device and increment reference + * @dev: get the group that this device belongs to + * + * This function is called by iommu drivers and users to get the group + * for the specified device. If found, the group is returned and the group + * reference in incremented, else NULL. + */ +struct iommu_group *iommu_group_get(struct device *dev) +{ + struct iommu_group *group = dev->iommu_group; + + if (group) + kobject_get(group->devices_kobj); + + return group; +} +EXPORT_SYMBOL_GPL(iommu_group_get); + +/** + * iommu_group_put - Decrement group reference + * @group: the group to use + * + * This function is called by iommu drivers and users to release the + * iommu group. Once the reference count is zero, the group is released. + */ +void iommu_group_put(struct iommu_group *group) +{ + if (group) + kobject_put(group->devices_kobj); +} +EXPORT_SYMBOL_GPL(iommu_group_put); + +/** + * iommu_group_register_notifier - Register a notifier for group changes + * @group: the group to watch + * @nb: notifier block to signal + * + * This function allows iommu group users to track changes in a group. + * See include/linux/iommu.h for actions sent via this notifier. Caller + * should hold a reference to the group throughout notifier registration. + */ +int iommu_group_register_notifier(struct iommu_group *group, + struct notifier_block *nb) +{ + return blocking_notifier_chain_register(&group->notifier, nb); +} +EXPORT_SYMBOL_GPL(iommu_group_register_notifier); + +/** + * iommu_group_unregister_notifier - Unregister a notifier + * @group: the group to watch + * @nb: notifier block to signal + * + * Unregister a previously registered group notifier block. + */ +int iommu_group_unregister_notifier(struct iommu_group *group, + struct notifier_block *nb) +{ + return blocking_notifier_chain_unregister(&group->notifier, nb); +} +EXPORT_SYMBOL_GPL(iommu_group_unregister_notifier); + +/** + * iommu_group_id - Return ID for a group + * @group: the group to ID + * + * Return the unique ID for the group matching the sysfs group number. + */ +int iommu_group_id(struct iommu_group *group) +{ + return group->id; +} +EXPORT_SYMBOL_GPL(iommu_group_id); -static int remove_iommu_group(struct device *dev) +static int add_iommu_group(struct device *dev, void *data) { - unsigned int groupid; + struct iommu_ops *ops = data; + + if (!ops->add_device) + return -ENODEV; - if (iommu_device_group(dev, &groupid) == 0) - device_remove_file(dev, &dev_attr_iommu_group); + WARN_ON(dev->iommu_group); + + ops->add_device(dev); return 0; } -static int iommu_device_notifier(struct notifier_block *nb, - unsigned long action, void *data) +static int iommu_bus_notifier(struct notifier_block *nb, + unsigned long action, void *data) { struct device *dev = data; + struct iommu_ops *ops = dev->bus->iommu_ops; + struct iommu_group *group; + unsigned long group_action = 0; + + /* + * ADD/DEL call into iommu driver ops if provided, which may + * result in ADD/DEL notifiers to group->notifier + */ + if (action == BUS_NOTIFY_ADD_DEVICE) { + if (ops->add_device) + return ops->add_device(dev); + } else if (action == BUS_NOTIFY_DEL_DEVICE) { + if (ops->remove_device && dev->iommu_group) { + ops->remove_device(dev); + return 0; + } + } + + /* + * Remaining BUS_NOTIFYs get filtered and republished to the + * group, if anyone is listening + */ + group = iommu_group_get(dev); + if (!group) + return 0; + + switch (action) { + case BUS_NOTIFY_BIND_DRIVER: + group_action = IOMMU_GROUP_NOTIFY_BIND_DRIVER; + break; + case BUS_NOTIFY_BOUND_DRIVER: + group_action = IOMMU_GROUP_NOTIFY_BOUND_DRIVER; + break; + case BUS_NOTIFY_UNBIND_DRIVER: + group_action = IOMMU_GROUP_NOTIFY_UNBIND_DRIVER; + break; + case BUS_NOTIFY_UNBOUND_DRIVER: + group_action = IOMMU_GROUP_NOTIFY_UNBOUND_DRIVER; + break; + } - if (action == BUS_NOTIFY_ADD_DEVICE) - return add_iommu_group(dev, NULL); - else if (action == BUS_NOTIFY_DEL_DEVICE) - return remove_iommu_group(dev); + if (group_action) + blocking_notifier_call_chain(&group->notifier, + group_action, dev); + iommu_group_put(group); return 0; } -static struct notifier_block iommu_device_nb = { - .notifier_call = iommu_device_notifier, +static struct notifier_block iommu_bus_nb = { + .notifier_call = iommu_bus_notifier, }; static void iommu_bus_init(struct bus_type *bus, struct iommu_ops *ops) { - bus_register_notifier(bus, &iommu_device_nb); - bus_for_each_dev(bus, NULL, NULL, add_iommu_group); + bus_register_notifier(bus, &iommu_bus_nb); + bus_for_each_dev(bus, NULL, ops, add_iommu_group); } /** @@ -192,6 +667,45 @@ void iommu_detach_device(struct iommu_domain *domain, struct device *dev) } EXPORT_SYMBOL_GPL(iommu_detach_device); +/* + * IOMMU groups are really the natrual working unit of the IOMMU, but + * the IOMMU API works on domains and devices. Bridge that gap by + * iterating over the devices in a group. Ideally we'd have a single + * device which represents the requestor ID of the group, but we also + * allow IOMMU drivers to create policy defined minimum sets, where + * the physical hardware may be able to distiguish members, but we + * wish to group them at a higher level (ex. untrusted multi-function + * PCI devices). Thus we attach each device. + */ +static int iommu_group_do_attach_device(struct device *dev, void *data) +{ + struct iommu_domain *domain = data; + + return iommu_attach_device(domain, dev); +} + +int iommu_attach_group(struct iommu_domain *domain, struct iommu_group *group) +{ + return iommu_group_for_each_dev(group, domain, + iommu_group_do_attach_device); +} +EXPORT_SYMBOL_GPL(iommu_attach_group); + +static int iommu_group_do_detach_device(struct device *dev, void *data) +{ + struct iommu_domain *domain = data; + + iommu_detach_device(domain, dev); + + return 0; +} + +void iommu_detach_group(struct iommu_domain *domain, struct iommu_group *group) +{ + iommu_group_for_each_dev(group, domain, iommu_group_do_detach_device); +} +EXPORT_SYMBOL_GPL(iommu_detach_group); + phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, unsigned long iova) { @@ -336,11 +850,48 @@ size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova, size_t size) } EXPORT_SYMBOL_GPL(iommu_unmap); -int iommu_device_group(struct device *dev, unsigned int *groupid) +static int __init iommu_init(void) { - if (iommu_present(dev->bus) && dev->bus->iommu_ops->device_group) - return dev->bus->iommu_ops->device_group(dev, groupid); + iommu_group_kset = kset_create_and_add("iommu_groups", + NULL, kernel_kobj); + ida_init(&iommu_group_ida); + mutex_init(&iommu_group_mutex); + + BUG_ON(!iommu_group_kset); + + return 0; +} +subsys_initcall(iommu_init); + +int iommu_domain_get_attr(struct iommu_domain *domain, + enum iommu_attr attr, void *data) +{ + struct iommu_domain_geometry *geometry; + int ret = 0; + + switch (attr) { + case DOMAIN_ATTR_GEOMETRY: + geometry = data; + *geometry = domain->geometry; + + break; + default: + if (!domain->ops->domain_get_attr) + return -EINVAL; + + ret = domain->ops->domain_get_attr(domain, attr, data); + } + + return ret; +} +EXPORT_SYMBOL_GPL(iommu_domain_get_attr); + +int iommu_domain_set_attr(struct iommu_domain *domain, + enum iommu_attr attr, void *data) +{ + if (!domain->ops->domain_set_attr) + return -EINVAL; - return -ENODEV; + return domain->ops->domain_set_attr(domain, attr, data); } -EXPORT_SYMBOL_GPL(iommu_device_group); +EXPORT_SYMBOL_GPL(iommu_domain_set_attr); |