diff options
Diffstat (limited to 'drivers/iommu/intel-pasid.c')
-rw-r--r-- | drivers/iommu/intel-pasid.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/drivers/iommu/intel-pasid.c b/drivers/iommu/intel-pasid.c new file mode 100644 index 000000000000..e918fe01ce7f --- /dev/null +++ b/drivers/iommu/intel-pasid.c @@ -0,0 +1,60 @@ +// SPDX-License-Identifier: GPL-2.0 +/** + * intel-pasid.c - PASID idr, table and entry manipulation + * + * Copyright (C) 2018 Intel Corporation + * + * Author: Lu Baolu <baolu.lu@linux.intel.com> + */ + +#define pr_fmt(fmt) "DMAR: " fmt + +#include <linux/dmar.h> +#include <linux/intel-iommu.h> +#include <linux/iommu.h> +#include <linux/memory.h> +#include <linux/spinlock.h> + +#include "intel-pasid.h" + +/* + * Intel IOMMU system wide PASID name space: + */ +static DEFINE_SPINLOCK(pasid_lock); +u32 intel_pasid_max_id = PASID_MAX; +static DEFINE_IDR(pasid_idr); + +int intel_pasid_alloc_id(void *ptr, int start, int end, gfp_t gfp) +{ + int ret, min, max; + + min = max_t(int, start, PASID_MIN); + max = min_t(int, end, intel_pasid_max_id); + + WARN_ON(in_interrupt()); + idr_preload(gfp); + spin_lock(&pasid_lock); + ret = idr_alloc(&pasid_idr, ptr, min, max, GFP_ATOMIC); + spin_unlock(&pasid_lock); + idr_preload_end(); + + return ret; +} + +void intel_pasid_free_id(int pasid) +{ + spin_lock(&pasid_lock); + idr_remove(&pasid_idr, pasid); + spin_unlock(&pasid_lock); +} + +void *intel_pasid_lookup_id(int pasid) +{ + void *p; + + spin_lock(&pasid_lock); + p = idr_find(&pasid_idr, pasid); + spin_unlock(&pasid_lock); + + return p; +} |