Subject: Re: [PATCH kernel v8 12/31] powerpc/spapr: vfio: Switch from iommu_table to new iommu_table_group

From: Alexey Kardashevskiy <[email-masked]>
Date: Fri, 17 Apr 2015 01:48:13 +1000

On 04/16/2015 03:55 PM, David Gibson wrote:
> On Fri, Apr 10, 2015 at 04:30:54PM +1000, Alexey Kardashevskiy wrote:
>> Modern IBM POWERPC systems support multiple (currently two) TCE tables
>> per IOMMU group (a.k.a. PE). This adds a iommu_table_group container
>> for TCE tables. Right now just one table is supported.
>>
>> Signed-off-by: Alexey Kardashevskiy <[email-masked]>
>> ---
>>   arch/powerpc/include/asm/iommu.h            |  18 +++--
>>   arch/powerpc/kernel/iommu.c                 |  34 ++++----
>>   arch/powerpc/platforms/powernv/pci-ioda.c   |  38 +++++----
>>   arch/powerpc/platforms/powernv/pci-p5ioc2.c |  17 ++--
>>   arch/powerpc/platforms/powernv/pci.c        |   2 +-
>>   arch/powerpc/platforms/powernv/pci.h        |   4 +-
>>   arch/powerpc/platforms/pseries/iommu.c      |   9 ++-
>>   drivers/vfio/vfio_iommu_spapr_tce.c         | 120 ++++++++++++++++++++--------
>>   8 files changed, 160 insertions(+), 82 deletions(-)
>>
>> diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h
>> index eb75726..667aa1a 100644
>> --- a/arch/powerpc/include/asm/iommu.h
>> +++ b/arch/powerpc/include/asm/iommu.h
>> @@ -90,9 +90,7 @@ struct iommu_table {
>>   	struct iommu_pool pools[IOMMU_NR_POOLS];
>>   	unsigned long *it_map;       /* A simple allocation bitmap for now */
>>   	unsigned long  it_page_shift;/* table iommu page size */
>> -#ifdef CONFIG_IOMMU_API
>> -	struct iommu_group *it_group;
>> -#endif
>> +	struct iommu_table_group *it_group;
>>   	struct iommu_table_ops *it_ops;
>>   	void (*set_bypass)(struct iommu_table *tbl, bool enable);
>>   };
>> @@ -126,14 +124,24 @@ extern void iommu_free_table(struct iommu_table *tbl, const char *node_name);
>>    */
>>   extern struct iommu_table *iommu_init_table(struct iommu_table * tbl,
>>   					    int nid);
>> +
>> +#define IOMMU_TABLE_GROUP_MAX_TABLES	1
>> +
>> +struct iommu_table_group {
>>   #ifdef CONFIG_IOMMU_API
>> -extern void iommu_register_group(struct iommu_table *tbl,
>> +	struct iommu_group *group;
>> +#endif
>> +	struct iommu_table tables[IOMMU_TABLE_GROUP_MAX_TABLES];
>
> There's nothing to indicate which of the tables are in use at the
> current time.  I mean, it doesn't matter now because there's only one,
> but the patch doesn't make a whole lot of sense without that.
>
>> +};
>> +
>> +#ifdef CONFIG_IOMMU_API
>> +extern void iommu_register_group(struct iommu_table_group *table_group,
>>   				 int pci_domain_number, unsigned long pe_num);
>>   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);
>>   #else
>> -static inline void iommu_register_group(struct iommu_table *tbl,
>> +static inline void iommu_register_group(struct iommu_table_group *table_group,
>>   					int pci_domain_number,
>>   					unsigned long pe_num)
>>   {
>> diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
>> index b39d00a..fd49c8e 100644
>> --- a/arch/powerpc/kernel/iommu.c
>> +++ b/arch/powerpc/kernel/iommu.c
>> @@ -712,17 +712,20 @@ struct iommu_table *iommu_init_table(struct iommu_table *tbl, int nid)
>>
>>   struct iommu_table *iommu_table_alloc(int node)
>>   {
>> -	struct iommu_table *tbl;
>> +	struct iommu_table_group *table_group;
>>
>> -	tbl = kzalloc_node(sizeof(struct iommu_table), GFP_KERNEL, node);
>> +	table_group = kzalloc_node(sizeof(struct iommu_table_group), GFP_KERNEL,
>> +			   node);
>> +	table_group->tables[0].it_group = table_group;
>>
>> -	return tbl;
>> +	return &table_group->tables[0];
>>   }
>>
>>   void iommu_free_table(struct iommu_table *tbl, const char *node_name)
>
> Surely the free function should take a table group rather than a table
> as argument.

No, it should not. Tables lifetime is not the same even within the same group.

>
>>   {
>>   	unsigned long bitmap_sz;
>>   	unsigned int order;
>> +	struct iommu_table_group *table_group = tbl->it_group;
>>
>>   	if (!tbl || !tbl->it_map) {
>>   		printk(KERN_ERR "%s: expected TCE map for %s\n", __func__,
>> @@ -738,9 +741,9 @@ void iommu_free_table(struct iommu_table *tbl, const char *node_name)
>>   		clear_bit(0, tbl->it_map);
>>
>>   #ifdef CONFIG_IOMMU_API
>> -	if (tbl->it_group) {
>> -		iommu_group_put(tbl->it_group);
>> -		BUG_ON(tbl->it_group);
>> +	if (table_group->group) {
>> +		iommu_group_put(table_group->group);
>> +		BUG_ON(table_group->group);
>>   	}
>>   #endif
>>
>> @@ -756,7 +759,7 @@ void iommu_free_table(struct iommu_table *tbl, const char *node_name)
>>   	free_pages((unsigned long) tbl->it_map, order);
>>
>>   	/* free table */
>> -	kfree(tbl);
>> +	kfree(table_group);
>>   }
>>
>>   /* Creates TCEs for a user provided buffer.  The user buffer must be
>> @@ -903,11 +906,12 @@ EXPORT_SYMBOL_GPL(iommu_direction_to_tce_perm);
>>    */
>>   static void group_release(void *iommu_data)
>>   {
>> -	struct iommu_table *tbl = iommu_data;
>> -	tbl->it_group = NULL;
>> +	struct iommu_table_group *table_group = iommu_data;
>> +
>> +	table_group->group = NULL;
>>   }
>>
>> -void iommu_register_group(struct iommu_table *tbl,
>> +void iommu_register_group(struct iommu_table_group *table_group,
>>   		int pci_domain_number, unsigned long pe_num)
>>   {
>>   	struct iommu_group *grp;
>> @@ -919,8 +923,8 @@ void iommu_register_group(struct iommu_table *tbl,
>>   				PTR_ERR(grp));
>>   		return;
>>   	}
>> -	tbl->it_group = grp;
>> -	iommu_group_set_iommudata(grp, tbl, group_release);
>> +	table_group->group = grp;
>> +	iommu_group_set_iommudata(grp, table_group, group_release);
>>   	name = kasprintf(GFP_KERNEL, "domain%d-pe%lx",
>>   			pci_domain_number, pe_num);
>>   	if (!name)
>> @@ -1108,7 +1112,7 @@ int iommu_add_device(struct device *dev)
>>   	}
>>
>>   	tbl = get_iommu_table_base(dev);
>> -	if (!tbl || !tbl->it_group) {
>> +	if (!tbl || !tbl->it_group || !tbl->it_group->group) {
>>   		pr_debug("%s: Skipping device %s with no tbl\n",
>>   			 __func__, dev_name(dev));
>>   		return 0;
>> @@ -1116,7 +1120,7 @@ int iommu_add_device(struct device *dev)
>>
>>   	pr_debug("%s: Adding %s to iommu group %d\n",
>>   		 __func__, dev_name(dev),
>> -		 iommu_group_id(tbl->it_group));
>> +		 iommu_group_id(tbl->it_group->group));
>>
>>   	if (PAGE_SIZE < IOMMU_PAGE_SIZE(tbl)) {
>>   		pr_err("%s: Invalid IOMMU page size %lx (%lx) on %s\n",
>> @@ -1125,7 +1129,7 @@ int iommu_add_device(struct device *dev)
>>   		return -EINVAL;
>>   	}
>>
>> -	return iommu_group_add_device(tbl->it_group, dev);
>> +	return iommu_group_add_device(tbl->it_group->group, dev);
>>   }
>>   EXPORT_SYMBOL_GPL(iommu_add_device);
>>
>> diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
>> index 85e64a5..a964c50 100644
>> --- a/arch/powerpc/platforms/powernv/pci-ioda.c
>> +++ b/arch/powerpc/platforms/powernv/pci-ioda.c
>> @@ -23,6 +23,7 @@
>>   #include <linux/io.h>
>>   #include <linux/msi.h>
>>   #include <linux/memblock.h>
>> +#include <linux/iommu.h>
>>
>>   #include <asm/sections.h>
>>   #include <asm/io.h>
>> @@ -989,7 +990,7 @@ 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_and_group(&pdev->dev, &pe->table_group.tables[0]);
>>   }
>>
>>   static int pnv_pci_ioda_dma_set_mask(struct pnv_phb *phb,
>> @@ -1016,7 +1017,7 @@ static int pnv_pci_ioda_dma_set_mask(struct pnv_phb *phb,
>>   	} else {
>>   		dev_info(&pdev->dev, "Using 32-bit DMA via iommu\n");
>>   		set_dma_ops(&pdev->dev, &dma_iommu_ops);
>> -		set_iommu_table_base(&pdev->dev, &pe->tce32_table);
>> +		set_iommu_table_base(&pdev->dev, &pe->table_group.tables[0]);
>>   	}
>>   	*pdev->dev.dma_mask = dma_mask;
>>   	return 0;
>> @@ -1053,9 +1054,10 @@ static void pnv_ioda_setup_bus_dma(struct pnv_ioda_pe *pe,
>>   	list_for_each_entry(dev, &bus->devices, bus_list) {
>>   		if (add_to_iommu_group)
>>   			set_iommu_table_base_and_group(&dev->dev,
>> -						       &pe->tce32_table);
>> +					&pe->table_group.tables[0]);
>>   		else
>> -			set_iommu_table_base(&dev->dev, &pe->tce32_table);
>> +			set_iommu_table_base(&dev->dev,
>> +					&pe->table_group.tables[0]);
>>
>>   		if (dev->subordinate)
>>   			pnv_ioda_setup_bus_dma(pe, dev->subordinate,
>> @@ -1145,8 +1147,8 @@ static void pnv_pci_ioda2_tce_invalidate(struct pnv_ioda_pe *pe,
>>   void pnv_pci_ioda_tce_invalidate(struct iommu_table *tbl,
>>   				 __be64 *startp, __be64 *endp, bool rm)
>>   {
>> -	struct pnv_ioda_pe *pe = container_of(tbl, struct pnv_ioda_pe,
>> -					      tce32_table);
>> +	struct pnv_ioda_pe *pe = container_of(tbl->it_group, struct pnv_ioda_pe,
>> +					      table_group);
>>   	struct pnv_phb *phb = pe->phb;
>>
>>   	if (phb->type == PNV_PHB_IODA1)
>> @@ -1211,8 +1213,11 @@ static void pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
>>   		}
>>   	}
>>
>> +	/* Setup iommu */
>> +	pe->table_group.tables[0].it_group = &pe->table_group;
>> +
>>   	/* Setup linux iommu table */
>> -	tbl = &pe->tce32_table;
>> +	tbl = &pe->table_group.tables[0];
>>   	pnv_pci_setup_iommu_table(tbl, addr, TCE32_TABLE_SIZE * segs,
>>   				  base << 28, IOMMU_PAGE_SHIFT_4K);
>>
>> @@ -1233,7 +1238,8 @@ static void pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
>>   	}
>>   	tbl->it_ops = &pnv_iommu_ops;
>>   	iommu_init_table(tbl, phb->hose->node);
>> -	iommu_register_group(tbl, phb->hose->global_number, pe->pe_number);
>> +	iommu_register_group(&pe->table_group, phb->hose->global_number,
>> +			pe->pe_number);
>>
>>   	if (pe->pdev)
>>   		set_iommu_table_base_and_group(&pe->pdev->dev, tbl);
>> @@ -1251,8 +1257,8 @@ static void pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
>>
>>   static void pnv_pci_ioda2_set_bypass(struct iommu_table *tbl, bool enable)
>>   {
>> -	struct pnv_ioda_pe *pe = container_of(tbl, struct pnv_ioda_pe,
>> -					      tce32_table);
>> +	struct pnv_ioda_pe *pe = container_of(tbl->it_group, struct pnv_ioda_pe,
>> +					      table_group);
>>   	uint16_t window_id = (pe->pe_number << 1 ) + 1;
>>   	int64_t rc;
>>
>> @@ -1297,10 +1303,10 @@ static void pnv_pci_ioda2_setup_bypass_pe(struct pnv_phb *phb,
>>   	pe->tce_bypass_base = 1ull << 59;
>>
>>   	/* Install set_bypass callback for VFIO */
>> -	pe->tce32_table.set_bypass = pnv_pci_ioda2_set_bypass;
>> +	pe->table_group.tables[0].set_bypass = pnv_pci_ioda2_set_bypass;
>>
>>   	/* Enable bypass by default */
>> -	pnv_pci_ioda2_set_bypass(&pe->tce32_table, true);
>> +	pnv_pci_ioda2_set_bypass(&pe->table_group.tables[0], true);
>>   }
>>
>>   static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
>> @@ -1347,8 +1353,11 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
>>   		goto fail;
>>   	}
>>
>> +	/* Setup iommu */
>> +	pe->table_group.tables[0].it_group = &pe->table_group;
>> +
>>   	/* Setup linux iommu table */
>> -	tbl = &pe->tce32_table;
>> +	tbl = &pe->table_group.tables[0];
>>   	pnv_pci_setup_iommu_table(tbl, addr, tce_table_size, 0,
>>   			IOMMU_PAGE_SHIFT_4K);
>>
>> @@ -1367,7 +1376,8 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
>>   	}
>>   	tbl->it_ops = &pnv_iommu_ops;
>>   	iommu_init_table(tbl, phb->hose->node);
>> -	iommu_register_group(tbl, phb->hose->global_number, pe->pe_number);
>> +	iommu_register_group(&pe->table_group, phb->hose->global_number,
>> +			pe->pe_number);
>>
>>   	if (pe->pdev)
>>   		set_iommu_table_base_and_group(&pe->pdev->dev, tbl);
>> diff --git a/arch/powerpc/platforms/powernv/pci-p5ioc2.c b/arch/powerpc/platforms/powernv/pci-p5ioc2.c
>> index 0256fcc..ff68cac 100644
>> --- a/arch/powerpc/platforms/powernv/pci-p5ioc2.c
>> +++ b/arch/powerpc/platforms/powernv/pci-p5ioc2.c
>> @@ -86,14 +86,16 @@ static void pnv_pci_init_p5ioc2_msis(struct pnv_phb *phb) { }
>>   static void pnv_pci_p5ioc2_dma_dev_setup(struct pnv_phb *phb,
>>   					 struct pci_dev *pdev)
>>   {
>> -	if (phb->p5ioc2.iommu_table.it_map == NULL) {
>> -		phb->p5ioc2.iommu_table.it_ops = &pnv_iommu_ops;
>> -		iommu_init_table(&phb->p5ioc2.iommu_table, phb->hose->node);
>> -		iommu_register_group(&phb->p5ioc2.iommu_table,
>> +	if (phb->p5ioc2.table_group.tables[0].it_map == NULL) {
>> +		phb->p5ioc2.table_group.tables[0].it_ops = &pnv_iommu_ops;
>> +		iommu_init_table(&phb->p5ioc2.table_group.tables[0],
>> +				phb->hose->node);
>> +		iommu_register_group(&phb->p5ioc2.table_group,
>>   				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_and_group(&pdev->dev,
>> +			&phb->p5ioc2.table_group.tables[0]);
>>   }
>>
>>   static void __init pnv_pci_init_p5ioc2_phb(struct device_node *np, u64 hub_id,
>> @@ -167,9 +169,12 @@ static void __init pnv_pci_init_p5ioc2_phb(struct device_node *np, u64 hub_id,
>>   	/* Setup MSI support */
>>   	pnv_pci_init_p5ioc2_msis(phb);
>>
>> +	/* Setup iommu */
>> +	phb->p5ioc2.table_group.tables[0].it_group = &phb->p5ioc2.table_group;
>> +
>>   	/* Setup TCEs */
>>   	phb->dma_dev_setup = pnv_pci_p5ioc2_dma_dev_setup;
>> -	pnv_pci_setup_iommu_table(&phb->p5ioc2.iommu_table,
>> +	pnv_pci_setup_iommu_table(&phb->p5ioc2.table_group.tables[0],
>>   				  tce_mem, tce_size, 0,
>>   				  IOMMU_PAGE_SHIFT_4K);
>>   }
>> diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c
>> index 1c31ac8..3050cc8 100644
>> --- a/arch/powerpc/platforms/powernv/pci.c
>> +++ b/arch/powerpc/platforms/powernv/pci.c
>> @@ -687,7 +687,7 @@ static struct iommu_table *pnv_pci_setup_bml_iommu(struct pci_controller *hose)
>>   				  be32_to_cpup(sizep), 0, IOMMU_PAGE_SHIFT_4K);
>>   	tbl->it_ops = &pnv_iommu_ops;
>>   	iommu_init_table(tbl, hose->node);
>> -	iommu_register_group(tbl, pci_domain_nr(hose->bus), 0);
>> +	iommu_register_group(tbl->it_group, pci_domain_nr(hose->bus), 0);
>>
>>   	/* Deal with SW invalidated TCEs when needed (BML way) */
>>   	swinvp = of_get_property(hose->dn, "linux,tce-sw-invalidate-info",
>> diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h
>> index f726700..762d906 100644
>> --- a/arch/powerpc/platforms/powernv/pci.h
>> +++ b/arch/powerpc/platforms/powernv/pci.h
>> @@ -53,7 +53,7 @@ struct pnv_ioda_pe {
>>   	/* "Base" iommu table, ie, 4K TCEs, 32-bit DMA */
>>   	int			tce32_seg;
>>   	int			tce32_segcount;
>> -	struct iommu_table	tce32_table;
>> +	struct iommu_table_group table_group;
>>   	phys_addr_t		tce_inval_reg_phys;
>>
>>   	/* 64-bit TCE bypass region */
>> @@ -138,7 +138,7 @@ struct pnv_phb {
>>
>>   	union {
>>   		struct {
>> -			struct iommu_table iommu_table;
>> +			struct iommu_table_group table_group;
>>   		} p5ioc2;
>>
>>   		struct {
>> diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
>> index 41a8b14..75ea581 100644
>> --- a/arch/powerpc/platforms/pseries/iommu.c
>> +++ b/arch/powerpc/platforms/pseries/iommu.c
>> @@ -622,7 +622,7 @@ 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;
>>   	pci->iommu_table = iommu_init_table(tbl, pci->phb->node);
>> -	iommu_register_group(tbl, pci_domain_nr(bus), 0);
>> +	iommu_register_group(tbl->it_group, pci_domain_nr(bus), 0);
>>
>>   	/* Divide the rest (1.75GB) among the children */
>>   	pci->phb->dma_window_size = 0x80000000ul;
>> @@ -672,7 +672,7 @@ 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;
>>   		ppci->iommu_table = iommu_init_table(tbl, ppci->phb->node);
>> -		iommu_register_group(tbl, pci_domain_nr(bus), 0);
>> +		iommu_register_group(tbl->it_group, pci_domain_nr(bus), 0);
>>   		pr_debug("  created table: %p\n", ppci->iommu_table);
>>   	}
>>   }
>> @@ -699,7 +699,7 @@ static void pci_dma_dev_setup_pSeries(struct pci_dev *dev)
>>   		iommu_table_setparms(phb, dn, tbl);
>>   		tbl->it_ops = &iommu_table_pseries_ops;
>>   		PCI_DN(dn)->iommu_table = iommu_init_table(tbl, phb->node);
>> -		iommu_register_group(tbl, pci_domain_nr(phb->bus), 0);
>> +		iommu_register_group(tbl->it_group, pci_domain_nr(phb->bus), 0);
>>   		set_iommu_table_base_and_group(&dev->dev,
>>   					       PCI_DN(dn)->iommu_table);
>>   		return;
>> @@ -1121,7 +1121,8 @@ 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;
>>   		pci->iommu_table = iommu_init_table(tbl, pci->phb->node);
>> -		iommu_register_group(tbl, pci_domain_nr(pci->phb->bus), 0);
>> +		iommu_register_group(tbl->it_group,
>> +				pci_domain_nr(pci->phb->bus), 0);
>>   		pr_debug("  created table: %p\n", pci->iommu_table);
>>   	} else {
>>   		pr_debug("  found DMA window, table: %p\n", pci->iommu_table);
>> diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c
>> index 244c958..d61aad2 100644
>> --- a/drivers/vfio/vfio_iommu_spapr_tce.c
>> +++ b/drivers/vfio/vfio_iommu_spapr_tce.c
>> @@ -88,7 +88,7 @@ static void decrement_locked_vm(long npages)
>>    */
>>   struct tce_container {
>>   	struct mutex lock;
>> -	struct iommu_table *tbl;
>> +	struct iommu_group *grp;
>>   	bool enabled;
>>   	unsigned long locked_pages;
>>   };
>> @@ -103,13 +103,41 @@ static bool tce_page_is_contained(struct page *page, unsigned page_shift)
>>   	return (PAGE_SHIFT + compound_order(compound_head(page))) >= page_shift;
>>   }
>>
>> +static struct iommu_table *spapr_tce_find_table(
>> +		struct tce_container *container,
>> +		phys_addr_t ioba)
>> +{
>> +	long i;
>> +	struct iommu_table *ret = NULL;
>> +	struct iommu_table_group *table_group;
>> +
>> +	table_group = iommu_group_get_iommudata(container->grp);
>> +	if (!table_group)
>> +		return NULL;
>> +
>> +	for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
>> +		struct iommu_table *tbl = &table_group->tables[i];
>> +		unsigned long entry = ioba >> tbl->it_page_shift;
>> +		unsigned long start = tbl->it_offset;
>> +		unsigned long end = start + tbl->it_size;
>> +
>> +		if ((start <= entry) && (entry < end)) {
>> +			ret = tbl;
>> +			break;
>> +		}
>> +	}
>> +
>> +	return ret;
>> +}
>> +
>>   static int tce_iommu_enable(struct tce_container *container)
>>   {
>>   	int ret = 0;
>>   	unsigned long locked;
>> -	struct iommu_table *tbl = container->tbl;
>> +	struct iommu_table *tbl;
>> +	struct iommu_table_group *table_group;
>>
>> -	if (!container->tbl)
>> +	if (!container->grp)
>>   		return -ENXIO;
>>
>>   	if (!current->mm)
>> @@ -143,6 +171,11 @@ static int tce_iommu_enable(struct tce_container *container)
>>   	 * as this information is only available from KVM and VFIO is
>>   	 * KVM agnostic.
>>   	 */
>> +	table_group = iommu_group_get_iommudata(container->grp);
>> +	if (!table_group)
>> +		return -ENODEV;
>> +
>> +	tbl = &table_group->tables[0];
>>   	locked = (tbl->it_size << tbl->it_page_shift) >> PAGE_SHIFT;
>>   	ret = try_increment_locked_vm(locked);
>>   	if (ret)
>> @@ -193,15 +226,17 @@ static int tce_iommu_clear(struct tce_container *container,
>>   static void tce_iommu_release(void *iommu_data)
>>   {
>>   	struct tce_container *container = iommu_data;
>> -	struct iommu_table *tbl = container->tbl;
>> +	struct iommu_table *tbl;
>> +	struct iommu_table_group *table_group;
>>
>> -	WARN_ON(tbl && !tbl->it_group);
>> +	WARN_ON(container->grp);
>>
>> -	if (tbl) {
>> +	if (container->grp) {
>> +		table_group = iommu_group_get_iommudata(container->grp);
>> +		tbl = &table_group->tables[0];
>>   		tce_iommu_clear(container, tbl,	tbl->it_offset, tbl->it_size);
>>
>> -		if (tbl->it_group)
>> -			tce_iommu_detach_group(iommu_data, tbl->it_group);
>> +		tce_iommu_detach_group(iommu_data, container->grp);
>>   	}
>>
>>   	tce_iommu_disable(container);
>> @@ -329,9 +364,16 @@ static long tce_iommu_ioctl(void *iommu_data,
>>
>>   	case VFIO_IOMMU_SPAPR_TCE_GET_INFO: {
>>   		struct vfio_iommu_spapr_tce_info info;
>> -		struct iommu_table *tbl = container->tbl;
>> +		struct iommu_table *tbl;
>> +		struct iommu_table_group *table_group;
>>
>> -		if (WARN_ON(!tbl))
>> +		if (WARN_ON(!container->grp))
>> +			return -ENXIO;
>> +
>> +		table_group = iommu_group_get_iommudata(container->grp);
>> +
>> +		tbl = &table_group->tables[0];
>> +		if (WARN_ON_ONCE(!tbl))
>>   			return -ENXIO;
>>
>>   		minsz = offsetofend(struct vfio_iommu_spapr_tce_info,
>> @@ -354,17 +396,12 @@ static long tce_iommu_ioctl(void *iommu_data,
>>   	}
>>   	case VFIO_IOMMU_MAP_DMA: {
>>   		struct vfio_iommu_type1_dma_map param;
>> -		struct iommu_table *tbl = container->tbl;
>> +		struct iommu_table *tbl;
>>   		unsigned long tce;
>>
>>   		if (!container->enabled)
>>   			return -EPERM;
>>
>> -		if (!tbl)
>> -			return -ENXIO;
>> -
>> -		BUG_ON(!tbl->it_group);
>> -
>>   		minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);
>>
>>   		if (copy_from_user(&param, (void __user *)arg, minsz))
>> @@ -377,6 +414,10 @@ static long tce_iommu_ioctl(void *iommu_data,
>>   				VFIO_DMA_MAP_FLAG_WRITE))
>>   			return -EINVAL;
>>
>> +		tbl = spapr_tce_find_table(container, param.iova);
>> +		if (!tbl)
>> +			return -ENXIO;
>> +
>>   		if ((param.size & ~IOMMU_PAGE_MASK(tbl)) ||
>>   				(param.vaddr & ~IOMMU_PAGE_MASK(tbl)))
>>   			return -EINVAL;
>> @@ -402,14 +443,11 @@ static long tce_iommu_ioctl(void *iommu_data,
>>   	}
>>   	case VFIO_IOMMU_UNMAP_DMA: {
>>   		struct vfio_iommu_type1_dma_unmap param;
>> -		struct iommu_table *tbl = container->tbl;
>> +		struct iommu_table *tbl;
>>
>>   		if (!container->enabled)
>>   			return -EPERM;
>>
>> -		if (WARN_ON(!tbl))
>> -			return -ENXIO;
>> -
>>   		minsz = offsetofend(struct vfio_iommu_type1_dma_unmap,
>>   				size);
>>
>> @@ -423,6 +461,10 @@ static long tce_iommu_ioctl(void *iommu_data,
>>   		if (param.flags)
>>   			return -EINVAL;
>>
>> +		tbl = spapr_tce_find_table(container, param.iova);
>> +		if (!tbl)
>> +			return -ENXIO;
>> +
>>   		if (param.size & ~IOMMU_PAGE_MASK(tbl))
>>   			return -EINVAL;
>>
>> @@ -451,10 +493,10 @@ static long tce_iommu_ioctl(void *iommu_data,
>>   		mutex_unlock(&container->lock);
>>   		return 0;
>>   	case VFIO_EEH_PE_OP:
>> -		if (!container->tbl || !container->tbl->it_group)
>> +		if (!container->grp)
>>   			return -ENODEV;
>>
>> -		return vfio_spapr_iommu_eeh_ioctl(container->tbl->it_group,
>> +		return vfio_spapr_iommu_eeh_ioctl(container->grp,
>>   						  cmd, arg);
>>   	}
>>
>> @@ -466,16 +508,15 @@ static int tce_iommu_attach_group(void *iommu_data,
>>   {
>>   	int ret;
>>   	struct tce_container *container = iommu_data;
>> -	struct iommu_table *tbl = iommu_group_get_iommudata(iommu_group);
>> +	struct iommu_table_group *table_group;
>>
>> -	BUG_ON(!tbl);
>>   	mutex_lock(&container->lock);
>>
>>   	/* pr_debug("tce_vfio: Attaching group #%u to iommu %p\n",
>>   			iommu_group_id(iommu_group), iommu_group); */
>> -	if (container->tbl) {
>> +	if (container->grp) {
>>   		pr_warn("tce_vfio: Only one group per IOMMU container is allowed, existing id=%d, attaching id=%d\n",
>> -				iommu_group_id(container->tbl->it_group),
>> +				iommu_group_id(container->grp),
>>   				iommu_group_id(iommu_group));
>>   		ret = -EBUSY;
>>   		goto unlock_exit;
>> @@ -488,9 +529,15 @@ static int tce_iommu_attach_group(void *iommu_data,
>>   		goto unlock_exit;
>>   	}
>>
>> -	ret = iommu_take_ownership(tbl);
>> +	table_group = iommu_group_get_iommudata(iommu_group);
>> +	if (!table_group) {
>> +		ret = -ENXIO;
>> +		goto unlock_exit;
>> +	}
>> +
>> +	ret = iommu_take_ownership(&table_group->tables[0]);
>>   	if (!ret)
>> -		container->tbl = tbl;
>> +		container->grp = iommu_group;
>>
>>   unlock_exit:
>>   	mutex_unlock(&container->lock);
>> @@ -502,27 +549,30 @@ static void tce_iommu_detach_group(void *iommu_data,
>>   		struct iommu_group *iommu_group)
>>   {
>>   	struct tce_container *container = iommu_data;
>> -	struct iommu_table *tbl = iommu_group_get_iommudata(iommu_group);
>> +	struct iommu_table_group *table_group;
>>
>> -	BUG_ON(!tbl);
>>   	mutex_lock(&container->lock);
>> -	if (tbl != container->tbl) {
>> +	if (iommu_group != container->grp) {
>>   		pr_warn("tce_vfio: detaching group #%u, expected group is #%u\n",
>>   				iommu_group_id(iommu_group),
>> -				iommu_group_id(tbl->it_group));
>> +				iommu_group_id(container->grp));
>>   		goto unlock_exit;
>>   	}
>>
>>   	if (container->enabled) {
>>   		pr_warn("tce_vfio: detaching group #%u from enabled container, forcing disable\n",
>> -				iommu_group_id(tbl->it_group));
>> +				iommu_group_id(container->grp));
>>   		tce_iommu_disable(container);
>>   	}
>>
>>   	/* pr_debug("tce_vfio: detaching group #%u from iommu %p\n",
>>   	   iommu_group_id(iommu_group), iommu_group); */
>> -	container->tbl = NULL;
>> -	iommu_release_ownership(tbl);
>> +	container->grp = NULL;
>> +
>> +	table_group = iommu_group_get_iommudata(iommu_group);
>> +	BUG_ON(!table_group);
>> +
>> +	iommu_release_ownership(&table_group->tables[0]);
>>
>>   unlock_exit:
>>   	mutex_unlock(&container->lock);
>

-- 
Alexey