--- v11
+++ v7
@@ -1,460 +1,65 @@
-At the moment writing new TCE value to the IOMMU table fails with EBUSY
-if there is a valid entry already. However PAPR specification allows
-the guest to write new TCE value without clearing it first.
-
-Another problem this patch is addressing is the use of pool locks for
-external IOMMU users such as VFIO. The pool locks are to protect
-DMA page allocator rather than entries and since the host kernel does
-not control what pages are in use, there is no point in pool locks and
-exchange()+put_page(oldtce) is sufficient to avoid possible races.
-
-This adds an exchange() callback to iommu_table_ops which does the same
-thing as set() plus it returns replaced TCE and DMA direction so
-the caller can release the pages afterwards. The exchange() receives
-a physical address unlike set() which receives linear mapping address;
-and returns a physical address as the clear() does.
-
-This implements exchange() for P5IOC2/IODA/IODA2. This adds a requirement
-for a platform to have exchange() implemented in order to support VFIO.
-
-This replaces iommu_tce_build() and iommu_clear_tce() with
-a single iommu_tce_xchg().
-
-This makes sure that TCE permission bits are not set in TCE passed to
-IOMMU API as those are to be calculated by platform code from
-DMA direction.
-
-This moves SetPageDirty() to the IOMMU code to make it work for both
-VFIO ioctl interface in in-kernel TCE acceleration (when it becomes
-available later).
+This changes few functions to receive a iommu_table_group pointer
+rather than PE as they are going to be a part of upcoming
+iommu_table_group_ops callback set.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
-[aw: for the vfio related changes]
-Acked-by: Alex Williamson <alex.williamson@redhat.com>
---
-Changes:
-v10:
-* did s/tce/hpa/ in iommu_table_ops::exchange and tce_iommu_unuse_page()
-* removed permission bits check from iommu_tce_put_param_check as
-permission bits are not allowed in the address
-* added BUG_ON(*hpa & ~IOMMU_PAGE_MASK(tbl)) to pnv_tce_xchg()
+ arch/powerpc/platforms/powernv/pci-ioda.c | 13 ++++++++-----
+ 1 file changed, 8 insertions(+), 5 deletions(-)
-v9:
-* changed exchange() to work with physical addresses as these addresses
-are never accessed by the code and physical addresses are actual values
-we put into the IOMMU table
----
- arch/powerpc/include/asm/iommu.h | 22 ++++++++--
- arch/powerpc/kernel/iommu.c | 59 +++++++++------------------
- arch/powerpc/platforms/powernv/pci-ioda.c | 34 ++++++++++++++++
- arch/powerpc/platforms/powernv/pci-p5ioc2.c | 3 ++
- arch/powerpc/platforms/powernv/pci.c | 18 +++++++++
- arch/powerpc/platforms/powernv/pci.h | 2 +
- drivers/vfio/vfio_iommu_spapr_tce.c | 63 +++++++++++++++++------------
- 7 files changed, 132 insertions(+), 69 deletions(-)
-
-diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h
-index 489133c..4636734 100644
---- a/arch/powerpc/include/asm/iommu.h
-+++ b/arch/powerpc/include/asm/iommu.h
-@@ -45,13 +45,29 @@ extern int iommu_is_off;
- extern int iommu_force_on;
-
- struct iommu_table_ops {
-+ /*
-+ * When called with direction==DMA_NONE, it is equal to clear().
-+ * uaddr is a linear map address.
-+ */
- int (*set)(struct iommu_table *tbl,
- long index, long npages,
- unsigned long uaddr,
- enum dma_data_direction direction,
- struct dma_attrs *attrs);
-+#ifdef CONFIG_IOMMU_API
-+ /*
-+ * Exchanges existing TCE with new TCE plus direction bits;
-+ * returns old TCE and DMA direction mask.
-+ * @tce is a physical address.
-+ */
-+ int (*exchange)(struct iommu_table *tbl,
-+ long index,
-+ unsigned long *hpa,
-+ enum dma_data_direction *direction);
-+#endif
- void (*clear)(struct iommu_table *tbl,
- long index, long npages);
-+ /* get() returns a physical address */
- unsigned long (*get)(struct iommu_table *tbl, long index);
- void (*flush)(struct iommu_table *tbl);
- };
-@@ -153,6 +169,8 @@ extern void iommu_register_group(struct iommu_table_group *table_group,
- 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,
-@@ -225,10 +243,6 @@ extern int iommu_tce_clear_param_check(struct iommu_table *tbl,
- unsigned long npages);
- extern int iommu_tce_put_param_check(struct iommu_table *tbl,
- unsigned long ioba, unsigned long tce);
--extern int iommu_tce_build(struct iommu_table *tbl, unsigned long entry,
-- unsigned long hwaddr, enum dma_data_direction direction);
--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);
-diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
-index 1ae1034..e220511 100644
---- a/arch/powerpc/kernel/iommu.c
-+++ b/arch/powerpc/kernel/iommu.c
-@@ -965,10 +965,7 @@ EXPORT_SYMBOL_GPL(iommu_tce_clear_param_check);
- int iommu_tce_put_param_check(struct iommu_table *tbl,
- unsigned long ioba, unsigned long tce)
- {
-- if (!(tce & (TCE_PCI_WRITE | TCE_PCI_READ)))
-- return -EINVAL;
--
-- if (tce & ~(IOMMU_PAGE_MASK(tbl) | TCE_PCI_WRITE | TCE_PCI_READ))
-+ if (tce & ~IOMMU_PAGE_MASK(tbl))
- return -EINVAL;
-
- if (ioba & ~IOMMU_PAGE_MASK(tbl))
-@@ -985,44 +982,16 @@ int iommu_tce_put_param_check(struct iommu_table *tbl,
- }
- EXPORT_SYMBOL_GPL(iommu_tce_put_param_check);
-
--unsigned long iommu_clear_tce(struct iommu_table *tbl, unsigned long entry)
-+long iommu_tce_xchg(struct iommu_table *tbl, unsigned long entry,
-+ unsigned long *hpa, enum dma_data_direction *direction)
- {
-- unsigned long oldtce;
-- struct iommu_pool *pool = get_pool(tbl, entry);
-+ long ret;
-
-- spin_lock(&(pool->lock));
-+ ret = tbl->it_ops->exchange(tbl, entry, hpa, direction);
-
-- oldtce = tbl->it_ops->get(tbl, entry);
-- if (oldtce & (TCE_PCI_WRITE | TCE_PCI_READ))
-- tbl->it_ops->clear(tbl, entry, 1);
-- else
-- oldtce = 0;
--
-- spin_unlock(&(pool->lock));
--
-- return oldtce;
--}
--EXPORT_SYMBOL_GPL(iommu_clear_tce);
--
--/*
-- * hwaddr is a kernel virtual address here (0xc... bazillion),
-- * tce_build converts it to a physical address.
-- */
--int iommu_tce_build(struct iommu_table *tbl, unsigned long entry,
-- unsigned long hwaddr, enum dma_data_direction direction)
--{
-- int ret = -EBUSY;
-- unsigned long oldtce;
-- struct iommu_pool *pool = get_pool(tbl, entry);
--
-- spin_lock(&(pool->lock));
--
-- oldtce = tbl->it_ops->get(tbl, entry);
-- /* Add new entry if it is not busy */
-- if (!(oldtce & (TCE_PCI_WRITE | TCE_PCI_READ)))
-- ret = tbl->it_ops->set(tbl, entry, 1, hwaddr, direction, NULL);
--
-- spin_unlock(&(pool->lock));
-+ if (!ret && ((*direction == DMA_FROM_DEVICE) ||
-+ (*direction == DMA_BIDIRECTIONAL)))
-+ SetPageDirty(pfn_to_page(*hpa >> PAGE_SHIFT));
-
- /* if (unlikely(ret))
- pr_err("iommu_tce: %s failed on hwaddr=%lx ioba=%lx kva=%lx ret=%d\n",
-@@ -1031,13 +1000,23 @@ int iommu_tce_build(struct iommu_table *tbl, unsigned long entry,
-
- return ret;
- }
--EXPORT_SYMBOL_GPL(iommu_tce_build);
-+EXPORT_SYMBOL_GPL(iommu_tce_xchg);
-
- int iommu_take_ownership(struct iommu_table *tbl)
- {
- unsigned long flags, i, sz = (tbl->it_size + 7) >> 3;
- int ret = 0;
-
-+ /*
-+ * VFIO does not control TCE entries allocation and the guest
-+ * can write new TCEs on top of existing ones so iommu_tce_build()
-+ * must be able to release old pages. This functionality
-+ * requires exchange() callback defined so if it is not
-+ * implemented, we disallow taking ownership over the table.
-+ */
-+ if (!tbl->it_ops->exchange)
-+ return -EINVAL;
-+
- spin_lock_irqsave(&tbl->large_pool.lock, flags);
- for (i = 0; i < tbl->nr_pools; i++)
- spin_lock(&tbl->pools[i].lock);
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
-index 94fccc8..d7ac2d4 100644
+index 74e119c..80ea84d 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
-@@ -1737,6 +1737,20 @@ static int pnv_ioda1_tce_build(struct iommu_table *tbl, long index,
- return ret;
+@@ -1408,10 +1408,12 @@ static __be64 *pnv_alloc_tce_table(int nid,
+ return addr;
}
-+#ifdef CONFIG_IOMMU_API
-+static int pnv_ioda1_tce_xchg(struct iommu_table *tbl, long index,
-+ unsigned long *hpa, enum dma_data_direction *direction)
-+{
-+ long ret = pnv_tce_xchg(tbl, index, hpa, direction);
-+
-+ if (!ret && (tbl->it_type &
-+ (TCE_PCI_SWINV_CREATE | TCE_PCI_SWINV_FREE)))
-+ pnv_pci_ioda1_tce_invalidate(tbl, index, 1, false);
-+
-+ return ret;
-+}
-+#endif
-+
- static void pnv_ioda1_tce_free(struct iommu_table *tbl, long index,
- long npages)
+-static long pnv_pci_ioda2_create_table(struct pnv_ioda_pe *pe,
++static long pnv_pci_ioda2_create_table(struct iommu_table_group *table_group,
+ __u32 page_shift, __u64 window_size, __u32 levels,
+ struct iommu_table *tbl)
{
-@@ -1748,6 +1762,9 @@ static void pnv_ioda1_tce_free(struct iommu_table *tbl, long index,
-
- static struct iommu_table_ops pnv_ioda1_iommu_ops = {
- .set = pnv_ioda1_tce_build,
-+#ifdef CONFIG_IOMMU_API
-+ .exchange = pnv_ioda1_tce_xchg,
-+#endif
- .clear = pnv_ioda1_tce_free,
- .get = pnv_tce_get,
- };
-@@ -1823,6 +1840,20 @@ static int pnv_ioda2_tce_build(struct iommu_table *tbl, long index,
- return ret;
++ struct pnv_ioda_pe *pe = container_of(table_group, struct pnv_ioda_pe,
++ table_group);
+ int nid = pe->phb->hose->node;
+ void *addr;
+ unsigned long tce_table_size, left;
+@@ -1462,9 +1464,11 @@ static void pnv_pci_free_table(struct iommu_table *tbl)
+ iommu_reset_table(tbl, "ioda2");
}
-+#ifdef CONFIG_IOMMU_API
-+static int pnv_ioda2_tce_xchg(struct iommu_table *tbl, long index,
-+ unsigned long *hpa, enum dma_data_direction *direction)
-+{
-+ long ret = pnv_tce_xchg(tbl, index, hpa, direction);
-+
-+ if (!ret && (tbl->it_type &
-+ (TCE_PCI_SWINV_CREATE | TCE_PCI_SWINV_FREE)))
-+ pnv_pci_ioda2_tce_invalidate(tbl, index, 1, false);
-+
-+ return ret;
-+}
-+#endif
-+
- static void pnv_ioda2_tce_free(struct iommu_table *tbl, long index,
- long npages)
+-static long pnv_pci_ioda2_set_window(struct pnv_ioda_pe *pe,
++static long pnv_pci_ioda2_set_window(struct iommu_table_group *table_group,
+ struct iommu_table *tbl)
{
-@@ -1834,6 +1865,9 @@ static void pnv_ioda2_tce_free(struct iommu_table *tbl, long index,
++ struct pnv_ioda_pe *pe = container_of(table_group, struct pnv_ioda_pe,
++ table_group);
+ struct pnv_phb *phb = pe->phb;
+ const __be64 *swinvp;
+ int64_t rc;
+@@ -1599,12 +1603,11 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
- static struct iommu_table_ops pnv_ioda2_iommu_ops = {
- .set = pnv_ioda2_tce_build,
-+#ifdef CONFIG_IOMMU_API
-+ .exchange = pnv_ioda2_tce_xchg,
-+#endif
- .clear = pnv_ioda2_tce_free,
- .get = pnv_tce_get,
- };
-diff --git a/arch/powerpc/platforms/powernv/pci-p5ioc2.c b/arch/powerpc/platforms/powernv/pci-p5ioc2.c
-index b524b17..94c880c 100644
---- a/arch/powerpc/platforms/powernv/pci-p5ioc2.c
-+++ b/arch/powerpc/platforms/powernv/pci-p5ioc2.c
-@@ -85,6 +85,9 @@ static void pnv_pci_init_p5ioc2_msis(struct pnv_phb *phb) { }
+ /* The PE will reserve all possible 32-bits space */
+ pe->tce32_seg = 0;
+-
+ end = (1 << ilog2(phb->ioda.m32_pci_base));
+ pe_info(pe, "Setting up 32-bit TCE table at 0..%08x\n",
+ end);
- static struct iommu_table_ops pnv_p5ioc2_iommu_ops = {
- .set = pnv_tce_build,
-+#ifdef CONFIG_IOMMU_API
-+ .exchange = pnv_tce_xchg,
-+#endif
- .clear = pnv_tce_free,
- .get = pnv_tce_get,
- };
-diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c
-index b2a32d0..dce3bfd 100644
---- a/arch/powerpc/platforms/powernv/pci.c
-+++ b/arch/powerpc/platforms/powernv/pci.c
-@@ -598,6 +598,24 @@ int pnv_tce_build(struct iommu_table *tbl, long index, long npages,
- return 0;
- }
+- rc = pnv_pci_ioda2_create_table(pe, IOMMU_PAGE_SHIFT_4K,
++ rc = pnv_pci_ioda2_create_table(&pe->table_group, IOMMU_PAGE_SHIFT_4K,
+ phb->ioda.m32_pci_base,
+ POWERNV_IOMMU_DEFAULT_LEVELS, tbl);
+ if (rc) {
+@@ -1619,7 +1622,7 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
+ pe->table_group.ops = &pnv_pci_ioda2_ops;
+ #endif
-+#ifdef CONFIG_IOMMU_API
-+int pnv_tce_xchg(struct iommu_table *tbl, long index,
-+ unsigned long *hpa, enum dma_data_direction *direction)
-+{
-+ u64 proto_tce = iommu_direction_to_tce_perm(*direction);
-+ unsigned long newtce = *hpa | proto_tce, oldtce;
-+ unsigned long idx = index - tbl->it_offset;
-+
-+ BUG_ON(*hpa & ~IOMMU_PAGE_MASK(tbl));
-+
-+ oldtce = xchg(pnv_tce(tbl, idx), cpu_to_be64(newtce));
-+ *hpa = be64_to_cpu(oldtce) & ~(TCE_PCI_READ | TCE_PCI_WRITE);
-+ *direction = iommu_tce_direction(oldtce);
-+
-+ return 0;
-+}
-+#endif
-+
- void pnv_tce_free(struct iommu_table *tbl, long index, long npages)
- {
- long i;
-diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h
-index d1e6978..fc6be02 100644
---- a/arch/powerpc/platforms/powernv/pci.h
-+++ b/arch/powerpc/platforms/powernv/pci.h
-@@ -210,6 +210,8 @@ extern int pnv_tce_build(struct iommu_table *tbl, long index, long npages,
- unsigned long uaddr, enum dma_data_direction direction,
- struct dma_attrs *attrs);
- extern void pnv_tce_free(struct iommu_table *tbl, long index, long npages);
-+extern int pnv_tce_xchg(struct iommu_table *tbl, long index,
-+ unsigned long *hpa, enum dma_data_direction *direction);
- extern unsigned long pnv_tce_get(struct iommu_table *tbl, long index);
-
- void pnv_pci_dump_phb_diag_data(struct pci_controller *hose,
-diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c
-index 627d5a2..651c4ae 100644
---- a/drivers/vfio/vfio_iommu_spapr_tce.c
-+++ b/drivers/vfio/vfio_iommu_spapr_tce.c
-@@ -236,18 +236,11 @@ static void tce_iommu_release(void *iommu_data)
- }
-
- static void tce_iommu_unuse_page(struct tce_container *container,
-- unsigned long oldtce)
-+ unsigned long hpa)
- {
- struct page *page;
-
-- if (!(oldtce & (TCE_PCI_READ | TCE_PCI_WRITE)))
-- return;
--
-- page = pfn_to_page(oldtce >> PAGE_SHIFT);
--
-- if (oldtce & TCE_PCI_WRITE)
-- SetPageDirty(page);
--
-+ page = pfn_to_page(hpa >> PAGE_SHIFT);
- put_page(page);
- }
-
-@@ -255,14 +248,21 @@ static int tce_iommu_clear(struct tce_container *container,
- struct iommu_table *tbl,
- unsigned long entry, unsigned long pages)
- {
-- unsigned long oldtce;
-+ unsigned long oldhpa;
-+ long ret;
-+ enum dma_data_direction direction;
-
- for ( ; pages; --pages, ++entry) {
-- oldtce = iommu_clear_tce(tbl, entry);
-- if (!oldtce)
-+ direction = DMA_NONE;
-+ oldhpa = 0;
-+ ret = iommu_tce_xchg(tbl, entry, &oldhpa, &direction);
-+ if (ret)
- continue;
-
-- tce_iommu_unuse_page(container, oldtce);
-+ if (direction == DMA_NONE)
-+ continue;
-+
-+ tce_iommu_unuse_page(container, oldhpa);
- }
-
- return 0;
-@@ -284,12 +284,13 @@ static int tce_iommu_use_page(unsigned long tce, unsigned long *hpa)
-
- static long tce_iommu_build(struct tce_container *container,
- struct iommu_table *tbl,
-- unsigned long entry, unsigned long tce, unsigned long pages)
-+ unsigned long entry, unsigned long tce, unsigned long pages,
-+ enum dma_data_direction direction)
- {
- long i, ret = 0;
- struct page *page;
- unsigned long hpa;
-- enum dma_data_direction direction = iommu_tce_direction(tce);
-+ enum dma_data_direction dirtmp;
-
- for (i = 0; i < pages; ++i) {
- unsigned long offset = tce & IOMMU_PAGE_MASK(tbl) & ~PAGE_MASK;
-@@ -305,8 +306,8 @@ static long tce_iommu_build(struct tce_container *container,
- }
-
- hpa |= offset;
-- ret = iommu_tce_build(tbl, entry + i, (unsigned long) __va(hpa),
-- direction);
-+ dirtmp = direction;
-+ ret = iommu_tce_xchg(tbl, entry + i, &hpa, &dirtmp);
- if (ret) {
- tce_iommu_unuse_page(container, hpa);
- pr_err("iommu_tce: %s failed ioba=%lx, tce=%lx, ret=%ld\n",
-@@ -314,6 +315,10 @@ static long tce_iommu_build(struct tce_container *container,
- tce, ret);
- break;
- }
-+
-+ if (dirtmp != DMA_NONE)
-+ tce_iommu_unuse_page(container, hpa);
-+
- tce += IOMMU_PAGE_SIZE(tbl);
- }
-
-@@ -378,8 +383,8 @@ static long tce_iommu_ioctl(void *iommu_data,
- case VFIO_IOMMU_MAP_DMA: {
- struct vfio_iommu_type1_dma_map param;
- struct iommu_table *tbl = NULL;
-- unsigned long tce;
- long num;
-+ enum dma_data_direction direction;
-
- if (!container->enabled)
- return -EPERM;
-@@ -405,19 +410,27 @@ static long tce_iommu_ioctl(void *iommu_data,
- return -EINVAL;
-
- /* iova is checked by the IOMMU API */
-- tce = param.vaddr;
-- if (param.flags & VFIO_DMA_MAP_FLAG_READ)
-- tce |= TCE_PCI_READ;
-- if (param.flags & VFIO_DMA_MAP_FLAG_WRITE)
-- tce |= TCE_PCI_WRITE;
-+ if (param.flags & VFIO_DMA_MAP_FLAG_READ) {
-+ if (param.flags & VFIO_DMA_MAP_FLAG_WRITE)
-+ direction = DMA_BIDIRECTIONAL;
-+ else
-+ direction = DMA_TO_DEVICE;
-+ } else {
-+ if (param.flags & VFIO_DMA_MAP_FLAG_WRITE)
-+ direction = DMA_FROM_DEVICE;
-+ else
-+ return -EINVAL;
-+ }
-
-- ret = iommu_tce_put_param_check(tbl, param.iova, tce);
-+ ret = iommu_tce_put_param_check(tbl, param.iova, param.vaddr);
- if (ret)
- return ret;
-
- ret = tce_iommu_build(container, tbl,
- param.iova >> tbl->it_page_shift,
-- tce, param.size >> tbl->it_page_shift);
-+ param.vaddr,
-+ param.size >> tbl->it_page_shift,
-+ direction);
-
- iommu_flush_tce(tbl);
-
+- rc = pnv_pci_ioda2_set_window(pe, tbl);
++ rc = pnv_pci_ioda2_set_window(&pe->table_group, tbl);
+ if (rc) {
+ pe_err(pe, "Failed to configure 32-bit TCE table,"
+ " err %ld\n", rc);
--
-2.4.0.rc3.8.gfb3e7d5
+2.0.0