From ed96f228ba9725edf69385bffdc19ee5bb0ec641 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Wed, 23 Nov 2011 17:30:39 +0100 Subject: [PATCH] iommu/amd: Implement device aquisition code for IOMMUv2 This patch adds the amd_iommu_init_device() and amd_iommu_free_device() functions which make a device and the IOMMU ready for IOMMUv2 usage. Signed-off-by: Joerg Roedel --- drivers/iommu/amd_iommu_v2.c | 210 +++++++++++++++++++++++++++++++++++ include/linux/amd-iommu.h | 23 +++- 2 files changed, 232 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/amd_iommu_v2.c b/drivers/iommu/amd_iommu_v2.c index a19e07d11d12..bfceed25c186 100644 --- a/drivers/iommu/amd_iommu_v2.c +++ b/drivers/iommu/amd_iommu_v2.c @@ -16,20 +16,230 @@ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ +#include +#include #include +#include +#include +#include + +#include "amd_iommu_proto.h" MODULE_LICENSE("GPL v2"); MODULE_AUTHOR("Joerg Roedel "); +#define MAX_DEVICES 0x10000 +#define PRI_QUEUE_SIZE 512 + +struct pri_queue { + atomic_t inflight; + bool finish; +}; + +struct pasid_state { + struct list_head list; /* For global state-list */ + atomic_t count; /* Reference count */ + struct task_struct *task; /* Task bound to this PASID */ + struct mm_struct *mm; /* mm_struct for the faults */ + struct pri_queue pri[PRI_QUEUE_SIZE]; /* PRI tag states */ + struct device_state *device_state; /* Link to our device_state */ + int pasid; /* PASID index */ +}; + +struct device_state { + atomic_t count; + struct pci_dev *pdev; + struct pasid_state **states; + struct iommu_domain *domain; + int pasid_levels; + int max_pasids; + spinlock_t lock; +}; + +struct device_state **state_table; +static spinlock_t state_lock; + +/* List and lock for all pasid_states */ +static LIST_HEAD(pasid_state_list); + +static u16 device_id(struct pci_dev *pdev) +{ + u16 devid; + + devid = pdev->bus->number; + devid = (devid << 8) | pdev->devfn; + + return devid; +} + +static struct device_state *get_device_state(u16 devid) +{ + struct device_state *dev_state; + unsigned long flags; + + spin_lock_irqsave(&state_lock, flags); + dev_state = state_table[devid]; + if (dev_state != NULL) + atomic_inc(&dev_state->count); + spin_unlock_irqrestore(&state_lock, flags); + + return dev_state; +} + +static void free_device_state(struct device_state *dev_state) +{ + iommu_detach_device(dev_state->domain, &dev_state->pdev->dev); + iommu_domain_free(dev_state->domain); + kfree(dev_state); +} + +static void put_device_state(struct device_state *dev_state) +{ + if (atomic_dec_and_test(&dev_state->count)) + free_device_state(dev_state); +} + +int amd_iommu_init_device(struct pci_dev *pdev, int pasids) +{ + struct device_state *dev_state; + unsigned long flags; + int ret, tmp; + u16 devid; + + might_sleep(); + + if (!amd_iommu_v2_supported()) + return -ENODEV; + + if (pasids <= 0 || pasids > (PASID_MASK + 1)) + return -EINVAL; + + devid = device_id(pdev); + + dev_state = kzalloc(sizeof(*dev_state), GFP_KERNEL); + if (dev_state == NULL) + return -ENOMEM; + + spin_lock_init(&dev_state->lock); + dev_state->pdev = pdev; + + tmp = pasids; + for (dev_state->pasid_levels = 0; (tmp - 1) & ~0x1ff; tmp >>= 9) + dev_state->pasid_levels += 1; + + atomic_set(&dev_state->count, 1); + dev_state->max_pasids = pasids; + + ret = -ENOMEM; + dev_state->states = (void *)get_zeroed_page(GFP_KERNEL); + if (dev_state->states == NULL) + goto out_free_dev_state; + + dev_state->domain = iommu_domain_alloc(&pci_bus_type); + if (dev_state->domain == NULL) + goto out_free_states; + + amd_iommu_domain_direct_map(dev_state->domain); + + ret = amd_iommu_domain_enable_v2(dev_state->domain, pasids); + if (ret) + goto out_free_domain; + + ret = iommu_attach_device(dev_state->domain, &pdev->dev); + if (ret != 0) + goto out_free_domain; + + spin_lock_irqsave(&state_lock, flags); + + if (state_table[devid] != NULL) { + spin_unlock_irqrestore(&state_lock, flags); + ret = -EBUSY; + goto out_free_domain; + } + + state_table[devid] = dev_state; + + spin_unlock_irqrestore(&state_lock, flags); + + return 0; + +out_free_domain: + iommu_domain_free(dev_state->domain); + +out_free_states: + free_page((unsigned long)dev_state->states); + +out_free_dev_state: + kfree(dev_state); + + return ret; +} +EXPORT_SYMBOL(amd_iommu_init_device); + +void amd_iommu_free_device(struct pci_dev *pdev) +{ + struct device_state *dev_state; + unsigned long flags; + u16 devid; + + if (!amd_iommu_v2_supported()) + return; + + devid = device_id(pdev); + + spin_lock_irqsave(&state_lock, flags); + + dev_state = state_table[devid]; + if (dev_state == NULL) { + spin_unlock_irqrestore(&state_lock, flags); + return; + } + + state_table[devid] = NULL; + + spin_unlock_irqrestore(&state_lock, flags); + + put_device_state(dev_state); +} +EXPORT_SYMBOL(amd_iommu_free_device); + static int __init amd_iommu_v2_init(void) { + size_t state_table_size; + pr_info("AMD IOMMUv2 driver by Joerg Roedel "); + spin_lock_init(&state_lock); + + state_table_size = MAX_DEVICES * sizeof(struct device_state *); + state_table = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, + get_order(state_table_size)); + if (state_table == NULL) + return -ENOMEM; + return 0; } static void __exit amd_iommu_v2_exit(void) { + struct device_state *dev_state; + size_t state_table_size; + int i; + + for (i = 0; i < MAX_DEVICES; ++i) { + dev_state = get_device_state(i); + + if (dev_state == NULL) + continue; + + WARN_ON_ONCE(1); + + amd_iommu_free_device(dev_state->pdev); + put_device_state(dev_state); + } + + state_table_size = MAX_DEVICES * sizeof(struct device_state *); + free_pages((unsigned long)state_table, get_order(state_table_size)); } module_init(amd_iommu_v2_init); diff --git a/include/linux/amd-iommu.h b/include/linux/amd-iommu.h index 4152c3073db4..e8c7a2ec86b3 100644 --- a/include/linux/amd-iommu.h +++ b/include/linux/amd-iommu.h @@ -20,10 +20,12 @@ #ifndef _ASM_X86_AMD_IOMMU_H #define _ASM_X86_AMD_IOMMU_H -#include +#include #ifdef CONFIG_AMD_IOMMU +struct pci_dev; + extern int amd_iommu_detect(void); @@ -33,6 +35,7 @@ extern int amd_iommu_detect(void); * @pdev: The PCI device the workaround is necessary for * @erratum: The erratum workaround to enable * + * The function needs to be called before amd_iommu_init_device(). * Possible values for the erratum number are for now: * - AMD_PRI_DEV_ERRATUM_ENABLE_RESET - Reset PRI capability when PRI * is enabled @@ -44,6 +47,24 @@ extern int amd_iommu_detect(void); extern void amd_iommu_enable_device_erratum(struct pci_dev *pdev, u32 erratum); +/** + * amd_iommu_init_device() - Init device for use with IOMMUv2 driver + * @pdev: The PCI device to initialize + * @pasids: Number of PASIDs to support for this device + * + * This function does all setup for the device pdev so that it can be + * used with IOMMUv2. + * Returns 0 on success or negative value on error. + */ +extern int amd_iommu_init_device(struct pci_dev *pdev, int pasids); + +/** + * amd_iommu_free_device() - Free all IOMMUv2 related device resources + * and disable IOMMUv2 usage for this device + * @pdev: The PCI device to disable IOMMUv2 usage for' + */ +extern void amd_iommu_free_device(struct pci_dev *pdev); + #else static inline int amd_iommu_detect(void) { return -ENODEV; } -- 2.20.1