lkml.org 
[lkml]   [2015]   [Mar]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH kernel v6 14/29] vfio: powerpc/spapr: powerpc/iommu: Rework IOMMU ownership control
Date
This replaces iommu_take_ownership()/iommu_release_ownership() calls
with the callback calls and it is up to the platform code to call
iommu_take_ownership()/iommu_release_ownership() if needed.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
---
arch/powerpc/include/asm/iommu.h | 4 +--
arch/powerpc/kernel/iommu.c | 50 ++++++++++++++++++++++++++++---------
drivers/vfio/vfio_iommu_spapr_tce.c | 4 +--
3 files changed, 42 insertions(+), 16 deletions(-)

diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h
index 667aa1a..b9e50d3 100644
--- a/arch/powerpc/include/asm/iommu.h
+++ b/arch/powerpc/include/asm/iommu.h
@@ -225,8 +225,8 @@ extern unsigned long iommu_clear_tce(struct iommu_table *tbl,
unsigned long entry);

extern void iommu_flush_tce(struct iommu_table *tbl);
-extern int iommu_take_ownership(struct iommu_table *tbl);
-extern void iommu_release_ownership(struct iommu_table *tbl);
+extern int iommu_take_ownership(struct iommu_table_group *table_group);
+extern void iommu_release_ownership(struct iommu_table_group *table_group);

extern enum dma_data_direction iommu_tce_direction(unsigned long tce);
extern unsigned long iommu_direction_to_tce_perm(enum dma_data_direction dir);
diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
index 7794dce..8358631 100644
--- a/arch/powerpc/kernel/iommu.c
+++ b/arch/powerpc/kernel/iommu.c
@@ -1050,7 +1050,7 @@ int iommu_tce_build(struct iommu_table *tbl, unsigned long entry,
}
EXPORT_SYMBOL_GPL(iommu_tce_build);

-int iommu_take_ownership(struct iommu_table *tbl)
+static int iommu_table_take_ownership(struct iommu_table *tbl)
{
unsigned long sz = (tbl->it_size + 7) >> 3;

@@ -1064,19 +1064,36 @@ int iommu_take_ownership(struct iommu_table *tbl)

memset(tbl->it_map, 0xff, sz);

- /*
- * Disable iommu bypass, otherwise the user can DMA to all of
- * our physical memory via the bypass window instead of just
- * the pages that has been explicitly mapped into the iommu
- */
- if (tbl->set_bypass)
- tbl->set_bypass(tbl, false);
+ return 0;
+}
+
+static void iommu_table_release_ownership(struct iommu_table *tbl);
+
+int iommu_take_ownership(struct iommu_table_group *table_group)
+{
+ int i, j, rc = 0;
+
+ for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
+ struct iommu_table *tbl = &table_group->tables[i];
+
+ if (!tbl->it_map)
+ continue;
+
+ rc = iommu_table_take_ownership(tbl);
+ if (rc) {
+ for (j = 0; j < i; ++j)
+ iommu_table_release_ownership(
+ &table_group->tables[j]);
+
+ return rc;
+ }
+ }

return 0;
}
EXPORT_SYMBOL_GPL(iommu_take_ownership);

-void iommu_release_ownership(struct iommu_table *tbl)
+static void iommu_table_release_ownership(struct iommu_table *tbl)
{
unsigned long sz = (tbl->it_size + 7) >> 3;

@@ -1086,9 +1103,18 @@ void iommu_release_ownership(struct iommu_table *tbl)
if (tbl->it_offset == 0)
set_bit(0, tbl->it_map);

- /* The kernel owns the device now, we can restore the iommu bypass */
- if (tbl->set_bypass)
- tbl->set_bypass(tbl, true);
+}
+
+extern void iommu_release_ownership(struct iommu_table_group *table_group)
+{
+ int i;
+
+ for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
+ struct iommu_table *tbl = &table_group->tables[i];
+
+ if (tbl->it_map)
+ iommu_table_release_ownership(tbl);
+ }
}
EXPORT_SYMBOL_GPL(iommu_release_ownership);

diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c
index bfbe8bb..5d1762b 100644
--- a/drivers/vfio/vfio_iommu_spapr_tce.c
+++ b/drivers/vfio/vfio_iommu_spapr_tce.c
@@ -801,7 +801,7 @@ static int tce_iommu_attach_group(void *iommu_data,
goto unlock_exit;
}

- ret = iommu_take_ownership(&table_group->tables[0]);
+ ret = iommu_take_ownership(table_group);
if (!ret)
container->grp = iommu_group;

@@ -838,7 +838,7 @@ static void tce_iommu_detach_group(void *iommu_data,
table_group = iommu_group_get_iommudata(iommu_group);
BUG_ON(!table_group);

- iommu_release_ownership(&table_group->tables[0]);
+ iommu_release_ownership(table_group);

unlock_exit:
mutex_unlock(&container->lock);
--
2.0.0


\
 
 \ /
  Last update: 2015-03-13 09:41    [W:0.118 / U:20.524 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site