[PATCH kernel v11 02/34] powerpc/iommu/powernv: Get rid of set_iommu_table_base_and_group

From: Alexey Kardashevskiy
Date: Fri May 29 2015 - 04:46:19 EST


The set_iommu_table_base_and_group() name suggests that the function
sets table base and add a device to an IOMMU group.

The actual purpose for table base setting is to put some reference
into a device so later iommu_add_device() can get the IOMMU group
reference and the device to the group.

At the moment a group cannot be explicitly passed to iommu_add_device()
as we want it to work from the bus notifier, we can fix it later and
remove confusing calls of set_iommu_table_base().

This replaces set_iommu_table_base_and_group() with a couple of
set_iommu_table_base() + iommu_add_device() which makes reading the code
easier.

This adds few comments why set_iommu_table_base() and iommu_add_device()
are called where they are called.

For IODA1/2, this essentially removes iommu_add_device() call from
the pnv_pci_ioda_dma_dev_setup() as it will always fail at this particular
place:
- for physical PE, the device is already attached by iommu_add_device()
in pnv_pci_ioda_setup_dma_pe();
- for virtual PE, the sysfs entries are not ready to create all symlinks
so actual adding is happening in tce_iommu_bus_notifier.

Signed-off-by: Alexey Kardashevskiy <aik@xxxxxxxxx>
Reviewed-by: Gavin Shan <gwshan@xxxxxxxxxxxxxxxxxx>
---
Changes:
v10:
* new to the series
---
arch/powerpc/include/asm/iommu.h | 7 -------
arch/powerpc/platforms/powernv/pci-ioda.c | 27 +++++++++++++++++++++++----
arch/powerpc/platforms/powernv/pci-p5ioc2.c | 3 ++-
arch/powerpc/platforms/pseries/iommu.c | 15 ++++++++-------
4 files changed, 33 insertions(+), 19 deletions(-)

diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h
index 1e27d63..8353c86 100644
--- a/arch/powerpc/include/asm/iommu.h
+++ b/arch/powerpc/include/asm/iommu.h
@@ -140,13 +140,6 @@ static inline int __init tce_iommu_bus_notifier_init(void)
}
#endif /* !CONFIG_IOMMU_API */

-static inline void set_iommu_table_base_and_group(struct device *dev,
- void *base)
-{
- set_iommu_table_base(dev, base);
- iommu_add_device(dev);
-}
-
extern int ppc_iommu_map_sg(struct device *dev, struct iommu_table *tbl,
struct scatterlist *sglist, int nelems,
unsigned long mask,
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 2f092bb..9a77f3c 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -1598,7 +1598,13 @@ static void pnv_pci_ioda_dma_dev_setup(struct pnv_phb *phb, struct pci_dev *pdev

pe = &phb->ioda.pe_array[pdn->pe_number];
WARN_ON(get_dma_ops(&pdev->dev) != &dma_iommu_ops);
- set_iommu_table_base_and_group(&pdev->dev, pe->tce32_table);
+ set_iommu_table_base(&pdev->dev, pe->tce32_table);
+ /*
+ * Note: iommu_add_device() will fail here as
+ * for physical PE: the device is already added by now;
+ * for virtual PE: sysfs entries are not ready yet and
+ * tce_iommu_bus_notifier will add the device to a group later.
+ */
}

static int pnv_pci_ioda_dma_set_mask(struct pnv_phb *phb,
@@ -1659,7 +1665,8 @@ static void pnv_ioda_setup_bus_dma(struct pnv_ioda_pe *pe,
struct pci_dev *dev;

list_for_each_entry(dev, &bus->devices, bus_list) {
- set_iommu_table_base_and_group(&dev->dev, pe->tce32_table);
+ set_iommu_table_base(&dev->dev, pe->tce32_table);
+ iommu_add_device(&dev->dev);

if (dev->subordinate)
pnv_ioda_setup_bus_dma(pe, dev->subordinate);
@@ -1835,7 +1842,13 @@ static void pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
if (pe->flags & PNV_IODA_PE_DEV) {
iommu_register_group(tbl, phb->hose->global_number,
pe->pe_number);
- set_iommu_table_base_and_group(&pe->pdev->dev, tbl);
+ /*
+ * Setting table base here only for carrying iommu_group
+ * further down to let iommu_add_device() do the job.
+ * pnv_pci_ioda_dma_dev_setup will override it later anyway.
+ */
+ set_iommu_table_base(&pe->pdev->dev, tbl);
+ iommu_add_device(&pe->pdev->dev);
} else if (pe->flags & (PNV_IODA_PE_BUS | PNV_IODA_PE_BUS_ALL)) {
iommu_register_group(tbl, phb->hose->global_number,
pe->pe_number);
@@ -1963,7 +1976,13 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
if (pe->flags & PNV_IODA_PE_DEV) {
iommu_register_group(tbl, phb->hose->global_number,
pe->pe_number);
- set_iommu_table_base_and_group(&pe->pdev->dev, tbl);
+ /*
+ * Setting table base here only for carrying iommu_group
+ * further down to let iommu_add_device() do the job.
+ * pnv_pci_ioda_dma_dev_setup will override it later anyway.
+ */
+ set_iommu_table_base(&pe->pdev->dev, tbl);
+ iommu_add_device(&pe->pdev->dev);
} else if (pe->flags & (PNV_IODA_PE_BUS | PNV_IODA_PE_BUS_ALL)) {
iommu_register_group(tbl, phb->hose->global_number,
pe->pe_number);
diff --git a/arch/powerpc/platforms/powernv/pci-p5ioc2.c b/arch/powerpc/platforms/powernv/pci-p5ioc2.c
index 4729ca7..b17d93615 100644
--- a/arch/powerpc/platforms/powernv/pci-p5ioc2.c
+++ b/arch/powerpc/platforms/powernv/pci-p5ioc2.c
@@ -92,7 +92,8 @@ static void pnv_pci_p5ioc2_dma_dev_setup(struct pnv_phb *phb,
pci_domain_nr(phb->hose->bus), phb->opal_id);
}

- set_iommu_table_base_and_group(&pdev->dev, &phb->p5ioc2.iommu_table);
+ set_iommu_table_base(&pdev->dev, &phb->p5ioc2.iommu_table);
+ iommu_add_device(&pdev->dev);
}

static void __init pnv_pci_init_p5ioc2_phb(struct device_node *np, u64 hub_id,
diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
index 61d5a17..05ab06d 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -688,8 +688,8 @@ static void pci_dma_dev_setup_pSeries(struct pci_dev *dev)
iommu_table_setparms(phb, dn, tbl);
PCI_DN(dn)->iommu_table = iommu_init_table(tbl, phb->node);
iommu_register_group(tbl, pci_domain_nr(phb->bus), 0);
- set_iommu_table_base_and_group(&dev->dev,
- PCI_DN(dn)->iommu_table);
+ set_iommu_table_base(&dev->dev, tbl);
+ iommu_add_device(&dev->dev);
return;
}

@@ -700,10 +700,10 @@ static void pci_dma_dev_setup_pSeries(struct pci_dev *dev)
while (dn && PCI_DN(dn) && PCI_DN(dn)->iommu_table == NULL)
dn = dn->parent;

- if (dn && PCI_DN(dn))
- set_iommu_table_base_and_group(&dev->dev,
- PCI_DN(dn)->iommu_table);
- else
+ if (dn && PCI_DN(dn)) {
+ set_iommu_table_base(&dev->dev, PCI_DN(dn)->iommu_table);
+ iommu_add_device(&dev->dev);
+ } else
printk(KERN_WARNING "iommu: Device %s has no iommu table\n",
pci_name(dev));
}
@@ -1115,7 +1115,8 @@ static void pci_dma_dev_setup_pSeriesLP(struct pci_dev *dev)
pr_debug(" found DMA window, table: %p\n", pci->iommu_table);
}

- set_iommu_table_base_and_group(&dev->dev, pci->iommu_table);
+ set_iommu_table_base(&dev->dev, pci->iommu_table);
+ iommu_add_device(&dev->dev);
}

static int dma_set_mask_pSeriesLP(struct device *dev, u64 dma_mask)
--
2.4.0.rc3.8.gfb3e7d5

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