Re: [PATCH kernel v10 28/34] vfio: powerpc/spapr: powerpc/powernv/ioda: Define and implement DMA windows API
From: Alex Williamson
Date: Wed May 13 2015 - 17:31:27 EST
On Tue, 2015-05-12 at 01:39 +1000, Alexey Kardashevskiy wrote:
> This extends iommu_table_group_ops by a set of callbacks to support
> dynamic DMA windows management.
>
> create_table() creates a TCE table with specific parameters.
> it receives iommu_table_group to know nodeid in order to allocate
> TCE table memory closer to the PHB. The exact format of allocated
> multi-level table might be also specific to the PHB model (not
> the case now though).
> This callback calculated the DMA window offset on a PCI bus from @num
> and stores it in a just created table.
>
> set_window() sets the window at specified TVT index + @num on PHB.
>
> unset_window() unsets the window from specified TVT.
>
> This adds a free() callback to iommu_table_ops to free the memory
> (potentially a tree of tables) allocated for the TCE table.
>
> create_table() and free() are supposed to be called once per
> VFIO container and set_window()/unset_window() are supposed to be
> called for every group in a container.
>
> This adds IOMMU capabilities to iommu_table_group such as default
> 32bit window parameters and others. This makes use of new values in
> vfio_iommu_spapr_tce. IODA1/P5IOC2 do not support DDW so they do not
> advertise pagemasks to the userspace.
>
> Signed-off-by: Alexey Kardashevskiy <aik@xxxxxxxxx>
> ---
> Changes:
> v10:
> * squashed "vfio: powerpc/spapr: Use 32bit DMA window properties from table_group"
> into this
> * shortened the subject
>
> v9:
> * new in the series - to make the next patch simpler
> ---
> arch/powerpc/include/asm/iommu.h | 19 ++++++
> arch/powerpc/platforms/powernv/pci-ioda.c | 96 ++++++++++++++++++++++++++---
> arch/powerpc/platforms/powernv/pci-p5ioc2.c | 7 ++-
> drivers/vfio/vfio_iommu_spapr_tce.c | 19 +++---
> 4 files changed, 124 insertions(+), 17 deletions(-)
For vfio:
Acked-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
>
> diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h
> index a902159..2c41115 100644
> --- a/arch/powerpc/include/asm/iommu.h
> +++ b/arch/powerpc/include/asm/iommu.h
> @@ -70,6 +70,7 @@ struct iommu_table_ops {
> /* get() returns a physical address */
> unsigned long (*get)(struct iommu_table *tbl, long index);
> void (*flush)(struct iommu_table *tbl);
> + void (*free)(struct iommu_table *tbl);
> };
>
> /* These are used by VIO */
> @@ -150,6 +151,17 @@ extern struct iommu_table *iommu_init_table(struct iommu_table * tbl,
> struct iommu_table_group;
>
> struct iommu_table_group_ops {
> + long (*create_table)(struct iommu_table_group *table_group,
> + int num,
> + __u32 page_shift,
> + __u64 window_size,
> + __u32 levels,
> + struct iommu_table **ptbl);
> + long (*set_window)(struct iommu_table_group *table_group,
> + int num,
> + struct iommu_table *tblnew);
> + long (*unset_window)(struct iommu_table_group *table_group,
> + int num);
> /* Switch ownership from platform code to external user (e.g. VFIO) */
> void (*take_ownership)(struct iommu_table_group *table_group);
> /* Switch ownership from external user (e.g. VFIO) back to core */
> @@ -163,6 +175,13 @@ struct iommu_table_group_link {
> };
>
> struct iommu_table_group {
> + /* IOMMU properties */
> + __u32 tce32_start;
> + __u32 tce32_size;
> + __u64 pgsizes; /* Bitmap of supported page sizes */
> + __u32 max_dynamic_windows_supported;
> + __u32 max_levels;
> +
> struct iommu_group *group;
> struct iommu_table *tables[IOMMU_TABLE_GROUP_MAX_TABLES];
> struct iommu_table_group_ops *ops;
> diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
> index d2a1dcd..c1d1aef 100644
> --- a/arch/powerpc/platforms/powernv/pci-ioda.c
> +++ b/arch/powerpc/platforms/powernv/pci-ioda.c
> @@ -25,6 +25,7 @@
> #include <linux/memblock.h>
> #include <linux/iommu.h>
> #include <linux/rculist.h>
> +#include <linux/sizes.h>
>
> #include <asm/sections.h>
> #include <asm/io.h>
> @@ -1867,6 +1868,12 @@ static void pnv_ioda2_tce_free(struct iommu_table *tbl, long index,
> pnv_pci_ioda2_tce_invalidate(tbl, index, npages, false);
> }
>
> +static void pnv_ioda2_table_free(struct iommu_table *tbl)
> +{
> + pnv_pci_ioda2_table_free_pages(tbl);
> + iommu_free_table(tbl, "pnv");
> +}
> +
> static struct iommu_table_ops pnv_ioda2_iommu_ops = {
> .set = pnv_ioda2_tce_build,
> #ifdef CONFIG_IOMMU_API
> @@ -1874,6 +1881,7 @@ static struct iommu_table_ops pnv_ioda2_iommu_ops = {
> #endif
> .clear = pnv_ioda2_tce_free,
> .get = pnv_tce_get,
> + .free = pnv_ioda2_table_free,
> };
>
> static void pnv_pci_ioda_setup_opal_tce_kill(struct pnv_phb *phb,
> @@ -1960,6 +1968,8 @@ static void pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
> TCE_PCI_SWINV_PAIR);
>
> tbl->it_ops = &pnv_ioda1_iommu_ops;
> + pe->table_group.tce32_start = tbl->it_offset << tbl->it_page_shift;
> + pe->table_group.tce32_size = tbl->it_size << tbl->it_page_shift;
> iommu_init_table(tbl, phb->hose->node);
>
> if (pe->flags & PNV_IODA_PE_DEV) {
> @@ -1998,7 +2008,7 @@ static long pnv_pci_ioda2_set_window(struct iommu_table_group *table_group,
> const __u64 start_addr = tbl->it_offset << tbl->it_page_shift;
> const __u64 win_size = tbl->it_size << tbl->it_page_shift;
>
> - pe_info(pe, "Setting up window %llx..%llx pg=%x\n",
> + pe_info(pe, "Setting up window#%d %llx..%llx pg=%x\n", num,
> start_addr, start_addr + win_size - 1,
> 1UL << tbl->it_page_shift);
>
> @@ -2008,7 +2018,7 @@ static long pnv_pci_ioda2_set_window(struct iommu_table_group *table_group,
> */
> rc = opal_pci_map_pe_dma_window(phb->opal_id,
> pe->pe_number,
> - pe->pe_number << 1,
> + (pe->pe_number << 1) + num,
> tbl->it_indirect_levels + 1,
> __pa(tbl->it_base),
> size << 3,
> @@ -2054,6 +2064,66 @@ static void pnv_pci_ioda2_set_bypass(struct pnv_ioda_pe *pe, bool enable)
> }
>
> #ifdef CONFIG_IOMMU_API
> +static long pnv_pci_ioda2_table_alloc_pages(int nid, __u64 bus_offset,
> + __u32 page_shift, __u64 window_size, __u32 levels,
> + struct iommu_table *tbl);
> +
> +static long pnv_pci_ioda2_create_table(struct iommu_table_group *table_group,
> + int num, __u32 page_shift, __u64 window_size, __u32 levels,
> + struct iommu_table **ptbl)
> +{
> + struct pnv_ioda_pe *pe = container_of(table_group, struct pnv_ioda_pe,
> + table_group);
> + int nid = pe->phb->hose->node;
> + __u64 bus_offset = num ? pe->tce_bypass_base : table_group->tce32_start;
> + long ret;
> + struct iommu_table *tbl;
> +
> + tbl = pnv_pci_table_alloc(nid);
> + if (!tbl)
> + return -ENOMEM;
> +
> + ret = pnv_pci_ioda2_table_alloc_pages(nid,
> + bus_offset, page_shift, window_size,
> + levels, tbl);
> + if (ret) {
> + iommu_free_table(tbl, "pnv");
> + return ret;
> + }
> +
> + tbl->it_ops = &pnv_ioda2_iommu_ops;
> + if (pe->tce_inval_reg)
> + tbl->it_type |= (TCE_PCI_SWINV_CREATE | TCE_PCI_SWINV_FREE);
> +
> + *ptbl = tbl;
> +
> + return 0;
> +}
> +
> +static long pnv_pci_ioda2_unset_window(struct iommu_table_group *table_group,
> + int num)
> +{
> + struct pnv_ioda_pe *pe = container_of(table_group, struct pnv_ioda_pe,
> + table_group);
> + struct pnv_phb *phb = pe->phb;
> + long ret;
> +
> + pe_info(pe, "Removing DMA window #%d\n", num);
> +
> + ret = opal_pci_map_pe_dma_window(phb->opal_id, pe->pe_number,
> + (pe->pe_number << 1) + num,
> + 0/* levels */, 0/* table address */,
> + 0/* table size */, 0/* page size */);
> + if (ret)
> + pe_warn(pe, "Unmapping failed, ret = %ld\n", ret);
> + else
> + pnv_pci_ioda2_tvt_invalidate(pe);
> +
> + pnv_pci_unlink_table_and_group(table_group->tables[num], table_group);
> +
> + return ret;
> +}
> +
> static void pnv_ioda2_take_ownership(struct iommu_table_group *table_group)
> {
> struct pnv_ioda_pe *pe = container_of(table_group, struct pnv_ioda_pe,
> @@ -2073,6 +2143,9 @@ static void pnv_ioda2_release_ownership(struct iommu_table_group *table_group)
> }
>
> static struct iommu_table_group_ops pnv_pci_ioda2_ops = {
> + .create_table = pnv_pci_ioda2_create_table,
> + .set_window = pnv_pci_ioda2_set_window,
> + .unset_window = pnv_pci_ioda2_unset_window,
> .take_ownership = pnv_ioda2_take_ownership,
> .release_ownership = pnv_ioda2_release_ownership,
> };
> @@ -2207,7 +2280,7 @@ static void pnv_pci_ioda2_table_free_pages(struct iommu_table *tbl)
> static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
> struct pnv_ioda_pe *pe)
> {
> - struct iommu_table *tbl;
> + struct iommu_table *tbl = NULL;
> int64_t rc;
>
> /* We shouldn't already have a 32-bit DMA associated */
> @@ -2217,10 +2290,8 @@ 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;
>
> - tbl = pnv_pci_table_alloc(phb->hose->node);
> iommu_register_group(&pe->table_group, phb->hose->global_number,
> pe->pe_number);
> - pnv_pci_link_table_and_group(phb->hose->node, 0, tbl, &pe->table_group);
>
> pnv_pci_ioda_setup_opal_tce_kill(phb, pe);
>
> @@ -2230,13 +2301,22 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
> phb->ioda.m32_pci_base);
>
> /* Setup linux iommu table */
> - rc = pnv_pci_ioda2_table_alloc_pages(pe->phb->hose->node,
> - 0, IOMMU_PAGE_SHIFT_4K, phb->ioda.m32_pci_base,
> - POWERNV_IOMMU_DEFAULT_LEVELS, tbl);
> + pe->table_group.tce32_start = 0;
> + pe->table_group.tce32_size = phb->ioda.m32_pci_base;
> + pe->table_group.max_dynamic_windows_supported =
> + IOMMU_TABLE_GROUP_MAX_TABLES;
> + pe->table_group.max_levels = POWERNV_IOMMU_MAX_LEVELS;
> + pe->table_group.pgsizes = SZ_4K | SZ_64K | SZ_16M;
> +
> + rc = pnv_pci_ioda2_create_table(&pe->table_group, 0,
> + IOMMU_PAGE_SHIFT_4K,
> + pe->table_group.tce32_size,
> + POWERNV_IOMMU_DEFAULT_LEVELS, &tbl);
> if (rc) {
> pe_err(pe, "Failed to create 32-bit TCE table, err %ld", rc);
> goto fail;
> }
> + pnv_pci_link_table_and_group(phb->hose->node, 0, tbl, &pe->table_group);
>
> tbl->it_ops = &pnv_ioda2_iommu_ops;
> iommu_init_table(tbl, phb->hose->node);
> diff --git a/arch/powerpc/platforms/powernv/pci-p5ioc2.c b/arch/powerpc/platforms/powernv/pci-p5ioc2.c
> index 94c880c..a295660 100644
> --- a/arch/powerpc/platforms/powernv/pci-p5ioc2.c
> +++ b/arch/powerpc/platforms/powernv/pci-p5ioc2.c
> @@ -119,6 +119,8 @@ static void __init pnv_pci_init_p5ioc2_phb(struct device_node *np, u64 hub_id,
> u64 phb_id;
> int64_t rc;
> static int primary = 1;
> + struct iommu_table_group *table_group;
> + struct iommu_table *tbl;
>
> pr_info(" Initializing p5ioc2 PHB %s\n", np->full_name);
>
> @@ -193,7 +195,10 @@ static void __init pnv_pci_init_p5ioc2_phb(struct device_node *np, u64 hub_id,
> * hotplug or SRIOV on P5IOC2 and therefore iommu_free_table()
> * should not be called for phb->p5ioc2.table_group.tables[0] ever.
> */
> - phb->p5ioc2.table_group.tables[0] = &phb->p5ioc2.iommu_table;
> + tbl = phb->p5ioc2.table_group.tables[0] = &phb->p5ioc2.iommu_table;
> + table_group = &phb->p5ioc2.table_group;
> + table_group->tce32_start = tbl->it_offset << tbl->it_page_shift;
> + table_group->tce32_size = tbl->it_size << tbl->it_page_shift;
> }
>
> void __init pnv_pci_init_p5ioc2_hub(struct device_node *np)
> diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c
> index 0724ec8..bc4956d 100644
> --- a/drivers/vfio/vfio_iommu_spapr_tce.c
> +++ b/drivers/vfio/vfio_iommu_spapr_tce.c
> @@ -135,7 +135,6 @@ static int tce_iommu_enable(struct tce_container *container)
> {
> int ret = 0;
> unsigned long locked;
> - struct iommu_table *tbl;
> struct iommu_table_group *table_group;
>
> if (!container->grp)
> @@ -171,13 +170,19 @@ static int tce_iommu_enable(struct tce_container *container)
> * this is that we cannot tell here the amount of RAM used by the guest
> * as this information is only available from KVM and VFIO is
> * KVM agnostic.
> + *
> + * So we do not allow enabling a container without a group attached
> + * as there is no way to know how much we should increment
> + * the locked_vm counter.
> */
> 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;
> + if (!table_group->tce32_size)
> + return -EPERM;
> +
> + locked = table_group->tce32_size >> PAGE_SHIFT;
> ret = try_increment_locked_vm(locked);
> if (ret)
> return ret;
> @@ -350,7 +355,6 @@ 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;
> struct iommu_table_group *table_group;
>
> if (WARN_ON(!container->grp))
> @@ -358,8 +362,7 @@ static long tce_iommu_ioctl(void *iommu_data,
>
> table_group = iommu_group_get_iommudata(container->grp);
>
> - tbl = table_group->tables[0];
> - if (WARN_ON_ONCE(!tbl))
> + if (!table_group)
> return -ENXIO;
>
> minsz = offsetofend(struct vfio_iommu_spapr_tce_info,
> @@ -371,8 +374,8 @@ static long tce_iommu_ioctl(void *iommu_data,
> if (info.argsz < minsz)
> return -EINVAL;
>
> - info.dma32_window_start = tbl->it_offset << tbl->it_page_shift;
> - info.dma32_window_size = tbl->it_size << tbl->it_page_shift;
> + info.dma32_window_start = table_group->tce32_start;
> + info.dma32_window_size = table_group->tce32_size;
> info.flags = 0;
>
> if (copy_to_user((void __user *)arg, &info, minsz))
--
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