IBM PPC IOMMU API users always set IOMMU data and IOMMU release callback
to an IOMMU group. At the moment the callback clears one pointer in
iommu_table_group and that's it.
The platform code calls iommu_group_put() and counts on _put() being
called last so they check for table_group->group being reset which
is conceptually wrong as there may be another user holding a reference.
This removes the default IOMMU group release() callback and adds it
as a parameter to iommu_register_group(). As we are changing the prototype
anyway, this also changes the function name to more distinctive
iommu_register_table_group().
This should cause no behavioral change as it leaves BUG_ON for IODA2
(where it was reported) and removes BUG_ON for pseries/IODA1 as they
do not support IOV anyway and this BUG_ON has never been reported for
these platforms.
Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru>
---
arch/powerpc/include/asm/iommu.h | 12 +++++++-----
arch/powerpc/kernel/iommu.c | 14 ++++----------
arch/powerpc/platforms/powernv/pci-ioda.c | 15 +++++++++++----
arch/powerpc/platforms/pseries/iommu.c | 17 +++++++++--------
4 files changed, 31 insertions(+), 27 deletions(-)
diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h
index 7b87bab..d7ba3b4 100644
--- a/arch/powerpc/include/asm/iommu.h
+++ b/arch/powerpc/include/asm/iommu.h
@@ -201,17 +201,19 @@ struct iommu_table_group {
#ifdef CONFIG_IOMMU_API
-extern void iommu_register_group(struct iommu_table_group *table_group,
- int pci_domain_number, unsigned long pe_num);
+extern void iommu_register_table_group(struct iommu_table_group *table_group,
+ int pci_domain_number, unsigned long pe_num,
+ void (*release)(void *iommu_data));
extern int iommu_add_device(struct device *dev);
extern void iommu_del_device(struct device *dev);
extern int __init tce_iommu_bus_notifier_init(void);
extern long iommu_tce_xchg(struct iommu_table *tbl, unsigned long entry,
unsigned long *hpa, enum dma_data_direction *direction);
#else
-static inline void iommu_register_group(struct iommu_table_group *table_group,
- int pci_domain_number,
- unsigned long pe_num)
+static inline void iommu_register_table_group(
+ struct iommu_table_group *table_group,
+ int pci_domain_number, unsigned long pe_num,
+ void (*release)(void *iommu_data))
{
}
diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
index a8e3490..8eed2fa 100644
--- a/arch/powerpc/kernel/iommu.c
+++ b/arch/powerpc/kernel/iommu.c
@@ -887,15 +887,9 @@ EXPORT_SYMBOL_GPL(iommu_direction_to_tce_perm);
/*
* SPAPR TCE API
*/
-static void group_release(void *iommu_data)
-{
- struct iommu_table_group *table_group = iommu_data;
-
- table_group->group = NULL;
-}
-
-void iommu_register_group(struct iommu_table_group *table_group,
- int pci_domain_number, unsigned long pe_num)
+void iommu_register_table_group(struct iommu_table_group *table_group,
+ int pci_domain_number, unsigned long pe_num,
+ void (*release)(void *iommu_data))
{
struct iommu_group *grp;
char *name;
@@ -907,7 +901,7 @@ void iommu_register_group(struct iommu_table_group
*table_group,
return;
}
table_group->group = grp;
- iommu_group_set_iommudata(grp, table_group, group_release);
+ iommu_group_set_iommudata(grp, table_group, release);
name = kasprintf(GFP_KERNEL, "domain%d-pe%lx",
pci_domain_number, pe_num);
if (!name)
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c
b/arch/powerpc/platforms/powernv/pci-ioda.c
index c5baaf3..ce9f2bf 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -1330,6 +1330,13 @@ static long pnv_pci_ioda2_unset_window(struct
iommu_table_group *table_group,
int num);
static void pnv_pci_ioda2_set_bypass(struct pnv_ioda_pe *pe, bool enable);
+static void pnv_pci_ioda2_group_release(void *iommu_data)
+{
+ struct iommu_table_group *table_group = iommu_data;
+
+ table_group->group = NULL;
+}
+
static void pnv_pci_ioda2_release_dma_pe(struct pci_dev *dev, struct
pnv_ioda_pe *pe)
{
struct iommu_table *tbl;
@@ -1965,8 +1972,8 @@ static void pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
return;
tbl = pnv_pci_table_alloc(phb->hose->node);
- iommu_register_group(&pe->table_group, phb->hose->global_number,
- pe->pe_number);
+ iommu_register_table_group(&pe->table_group, phb->hose->global_number,
+ pe->pe_number, NULL);
pnv_pci_link_table_and_group(phb->hose->node, 0, tbl, &pe->table_group);
/* Grab a 32-bit TCE table */
@@ -2450,8 +2457,8 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb
*phb,
/* TVE #1 is selected by PCI address bit 59 */
pe->tce_bypass_base = 1ull << 59;
- iommu_register_group(&pe->table_group, phb->hose->global_number,
- pe->pe_number);
+ iommu_register_table_group(&pe->table_group, phb->hose->global_number,
+ pe->pe_number, pnv_pci_ioda2_group_release);
/* The PE will reserve all possible 32-bits space */
pe->tce32_seg = 0;
diff --git a/arch/powerpc/platforms/pseries/iommu.c
b/arch/powerpc/platforms/pseries/iommu.c
index bd98ce2..0f6f06c 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -112,7 +112,7 @@ static void iommu_pseries_free_group(struct
iommu_table_group *table_group,
}
if (table_group->group) {
iommu_group_put(table_group->group);
- BUG_ON(table_group->group);
+ table_group->group = NULL;
}
#endif
iommu_free_table(tbl, node_name);
@@ -692,7 +692,8 @@ static void pci_dma_bus_setup_pSeries(struct pci_bus *bus)
iommu_table_setparms(pci->phb, dn, tbl);
tbl->it_ops = &iommu_table_pseries_ops;
iommu_init_table(tbl, pci->phb->node);
- iommu_register_group(pci->table_group, pci_domain_nr(bus), 0);
+ iommu_register_table_group(pci->table_group, pci_domain_nr(bus), 0,
+ NULL);
/* Divide the rest (1.75GB) among the children */
pci->phb->dma_window_size = 0x80000000ul;
@@ -743,8 +744,8 @@ static void pci_dma_bus_setup_pSeriesLP(struct pci_bus *bus)
iommu_table_setparms_lpar(ppci->phb, pdn, tbl, dma_window);
tbl->it_ops = &iommu_table_lpar_multi_ops;
iommu_init_table(tbl, ppci->phb->node);
- iommu_register_group(ppci->table_group,
- pci_domain_nr(bus), 0);
+ iommu_register_table_group(ppci->table_group,
+ pci_domain_nr(bus), 0, NULL);
pr_debug(" created table: %p\n", ppci->table_group);
}
}
@@ -772,8 +773,8 @@ static void pci_dma_dev_setup_pSeries(struct pci_dev *dev)
iommu_table_setparms(phb, dn, tbl);
tbl->it_ops = &iommu_table_pseries_ops;
iommu_init_table(tbl, phb->node);
- iommu_register_group(PCI_DN(dn)->table_group,
- pci_domain_nr(phb->bus), 0);
+ iommu_register_table_group(PCI_DN(dn)->table_group,
+ pci_domain_nr(phb->bus), 0, NULL);
set_iommu_table_base(&dev->dev, tbl);
iommu_add_device(&dev->dev);
return;
@@ -1197,8 +1198,8 @@ static void pci_dma_dev_setup_pSeriesLP(struct pci_dev
*dev)
iommu_table_setparms_lpar(pci->phb, pdn, tbl, dma_window);
tbl->it_ops = &iommu_table_lpar_multi_ops;
iommu_init_table(tbl, pci->phb->node);
- iommu_register_group(pci->table_group,
- pci_domain_nr(pci->phb->bus), 0);
+ iommu_register_table_group(pci->table_group,
+ pci_domain_nr(pci->phb->bus), 0, NULL);
pr_debug(" created table: %p\n", pci->table_group);
} else {
pr_debug(" found DMA window, table: %p\n", pci->table_group);
--
2.5.0.rc3
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