iommu/sva: Stop using ioasid_set for SVA

Instead SVA drivers can use a simple global IDA to allocate PASIDs for
each mm_struct.

Future work would be to allow drivers using the SVA APIs to reserve global
PASIDs from this IDA for their internal use, eg with the DMA API PASID
support.

Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20230322200803.869130-5-jacob.jun.pan@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Jason Gunthorpe 2023-03-22 13:08:00 -07:00 committed by Joerg Roedel
parent 2bef9ba8ae
commit 4e14176ab1
2 changed files with 14 additions and 29 deletions

View File

@ -9,47 +9,34 @@
#include "iommu-sva.h"
static DEFINE_MUTEX(iommu_sva_lock);
static DECLARE_IOASID_SET(iommu_sva_pasid);
static DEFINE_IDA(iommu_global_pasid_ida);
/**
* iommu_sva_alloc_pasid - Allocate a PASID for the mm
* @mm: the mm
* @min: minimum PASID value (inclusive)
* @max: maximum PASID value (inclusive)
*
* Try to allocate a PASID for this mm, or take a reference to the existing one
* provided it fits within the [@min, @max] range. On success the PASID is
* available in mm->pasid and will be available for the lifetime of the mm.
*
* Returns 0 on success and < 0 on error.
*/
int iommu_sva_alloc_pasid(struct mm_struct *mm, ioasid_t min, ioasid_t max)
/* Allocate a PASID for the mm within range (inclusive) */
static int iommu_sva_alloc_pasid(struct mm_struct *mm, ioasid_t min, ioasid_t max)
{
int ret = 0;
ioasid_t pasid;
if (min == INVALID_IOASID || max == INVALID_IOASID ||
if (!pasid_valid(min) || !pasid_valid(max) ||
min == 0 || max < min)
return -EINVAL;
mutex_lock(&iommu_sva_lock);
/* Is a PASID already associated with this mm? */
if (pasid_valid(mm->pasid)) {
if (mm->pasid < min || mm->pasid >= max)
if (mm->pasid < min || mm->pasid > max)
ret = -EOVERFLOW;
goto out;
}
pasid = ioasid_alloc(&iommu_sva_pasid, min, max, mm);
if (!pasid_valid(pasid))
ret = -ENOMEM;
else
mm->pasid = pasid;
ret = ida_alloc_range(&iommu_global_pasid_ida, min, max, GFP_ATOMIC);
if (ret < 0)
goto out;
mm->pasid = ret;
ret = 0;
out:
mutex_unlock(&iommu_sva_lock);
return ret;
}
EXPORT_SYMBOL_GPL(iommu_sva_alloc_pasid);
/**
* iommu_sva_bind_device() - Bind a process address space to a device
@ -221,8 +208,8 @@ out_put_mm:
void mm_pasid_drop(struct mm_struct *mm)
{
if (pasid_valid(mm->pasid)) {
ioasid_free(mm->pasid);
mm->pasid = INVALID_IOASID;
}
if (likely(!pasid_valid(mm->pasid)))
return;
ida_free(&iommu_global_pasid_ida, mm->pasid);
}

View File

@ -8,8 +8,6 @@
#include <linux/ioasid.h>
#include <linux/mm_types.h>
int iommu_sva_alloc_pasid(struct mm_struct *mm, ioasid_t min, ioasid_t max);
/* I/O Page fault */
struct device;
struct iommu_fault;