On 3/14/23 4:41 AM, Jacob Pan wrote:
From: Jason Gunthorpe<jgg@xxxxxxxxxx>
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.
Signed-off-by: Jason Gunthorpe<jgg@xxxxxxxxxx>
Signed-off-by: Jacob Pan<jacob.jun.pan@xxxxxxxxxxxxxxx>
---
v5:
- Put removing iommu_sva_find() to a separate patch (Kevin)
- Make pasid allocation range to be inclusive (Tina)
- Simplified return code handling (Baolu)
v4:
- Keep GFP_ATOMIC flag for PASID allocation, will changed to
GFP_KERNEL in a separate patch.
---
drivers/iommu/iommu-sva.c | 43 ++++++++++++++-------------------------
drivers/iommu/iommu-sva.h | 2 --
2 files changed, 15 insertions(+), 30 deletions(-)
diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c
index 4f357ef14f04..d4640731727a 100644
--- a/drivers/iommu/iommu-sva.c
+++ b/drivers/iommu/iommu-sva.c
@@ -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 ||
- min == 0 || max < min)
+ if (!pasid_valid(min) || !pasid_valid(max) ||
+ min == 0 || max < min)
I still think the last line change is unnecessary. Otherwise, you
probably will get below CHECK warning:
CHECK: Alignment should match open parenthesis
#259: FILE: drivers/iommu/iommu-sva.c:20:
+ if (!pasid_valid(min) || !pasid_valid(max) ||
+ min == 0 || max < min)
Besides that,
Reviewed-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Best regards,
baolu
