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Diffstat (limited to 'drivers/vfio/vfio_iommu_spapr_tce.c')
-rw-r--r--drivers/vfio/vfio_iommu_spapr_tce.c1388
1 files changed, 1388 insertions, 0 deletions
diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c
new file mode 100644
index 000000000..ec53310f1
--- /dev/null
+++ b/drivers/vfio/vfio_iommu_spapr_tce.c
@@ -0,0 +1,1388 @@
+/*
+ * VFIO: IOMMU DMA mapping support for TCE on POWER
+ *
+ * Copyright (C) 2013 IBM Corp. All rights reserved.
+ * Author: Alexey Kardashevskiy <aik@ozlabs.ru>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Derived from original vfio_iommu_type1.c:
+ * Copyright (C) 2012 Red Hat, Inc. All rights reserved.
+ * Author: Alex Williamson <alex.williamson@redhat.com>
+ */
+
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/err.h>
+#include <linux/vfio.h>
+#include <linux/vmalloc.h>
+#include <linux/sched/mm.h>
+#include <linux/sched/signal.h>
+
+#include <asm/iommu.h>
+#include <asm/tce.h>
+#include <asm/mmu_context.h>
+
+#define DRIVER_VERSION "0.1"
+#define DRIVER_AUTHOR "aik@ozlabs.ru"
+#define DRIVER_DESC "VFIO IOMMU SPAPR TCE"
+
+static void tce_iommu_detach_group(void *iommu_data,
+ struct iommu_group *iommu_group);
+
+static long try_increment_locked_vm(struct mm_struct *mm, long npages)
+{
+ long ret = 0, locked, lock_limit;
+
+ if (WARN_ON_ONCE(!mm))
+ return -EPERM;
+
+ if (!npages)
+ return 0;
+
+ down_write(&mm->mmap_sem);
+ locked = mm->locked_vm + npages;
+ lock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
+ if (locked > lock_limit && !capable(CAP_IPC_LOCK))
+ ret = -ENOMEM;
+ else
+ mm->locked_vm += npages;
+
+ pr_debug("[%d] RLIMIT_MEMLOCK +%ld %ld/%ld%s\n", current->pid,
+ npages << PAGE_SHIFT,
+ mm->locked_vm << PAGE_SHIFT,
+ rlimit(RLIMIT_MEMLOCK),
+ ret ? " - exceeded" : "");
+
+ up_write(&mm->mmap_sem);
+
+ return ret;
+}
+
+static void decrement_locked_vm(struct mm_struct *mm, long npages)
+{
+ if (!mm || !npages)
+ return;
+
+ down_write(&mm->mmap_sem);
+ if (WARN_ON_ONCE(npages > mm->locked_vm))
+ npages = mm->locked_vm;
+ mm->locked_vm -= npages;
+ pr_debug("[%d] RLIMIT_MEMLOCK -%ld %ld/%ld\n", current->pid,
+ npages << PAGE_SHIFT,
+ mm->locked_vm << PAGE_SHIFT,
+ rlimit(RLIMIT_MEMLOCK));
+ up_write(&mm->mmap_sem);
+}
+
+/*
+ * VFIO IOMMU fd for SPAPR_TCE IOMMU implementation
+ *
+ * This code handles mapping and unmapping of user data buffers
+ * into DMA'ble space using the IOMMU
+ */
+
+struct tce_iommu_group {
+ struct list_head next;
+ struct iommu_group *grp;
+};
+
+/*
+ * A container needs to remember which preregistered region it has
+ * referenced to do proper cleanup at the userspace process exit.
+ */
+struct tce_iommu_prereg {
+ struct list_head next;
+ struct mm_iommu_table_group_mem_t *mem;
+};
+
+/*
+ * The container descriptor supports only a single group per container.
+ * Required by the API as the container is not supplied with the IOMMU group
+ * at the moment of initialization.
+ */
+struct tce_container {
+ struct mutex lock;
+ bool enabled;
+ bool v2;
+ bool def_window_pending;
+ unsigned long locked_pages;
+ struct mm_struct *mm;
+ struct iommu_table *tables[IOMMU_TABLE_GROUP_MAX_TABLES];
+ struct list_head group_list;
+ struct list_head prereg_list;
+};
+
+static long tce_iommu_mm_set(struct tce_container *container)
+{
+ if (container->mm) {
+ if (container->mm == current->mm)
+ return 0;
+ return -EPERM;
+ }
+ BUG_ON(!current->mm);
+ container->mm = current->mm;
+ atomic_inc(&container->mm->mm_count);
+
+ return 0;
+}
+
+static long tce_iommu_prereg_free(struct tce_container *container,
+ struct tce_iommu_prereg *tcemem)
+{
+ long ret;
+
+ ret = mm_iommu_put(container->mm, tcemem->mem);
+ if (ret)
+ return ret;
+
+ list_del(&tcemem->next);
+ kfree(tcemem);
+
+ return 0;
+}
+
+static long tce_iommu_unregister_pages(struct tce_container *container,
+ __u64 vaddr, __u64 size)
+{
+ struct mm_iommu_table_group_mem_t *mem;
+ struct tce_iommu_prereg *tcemem;
+ bool found = false;
+
+ if ((vaddr & ~PAGE_MASK) || (size & ~PAGE_MASK))
+ return -EINVAL;
+
+ mem = mm_iommu_find(container->mm, vaddr, size >> PAGE_SHIFT);
+ if (!mem)
+ return -ENOENT;
+
+ list_for_each_entry(tcemem, &container->prereg_list, next) {
+ if (tcemem->mem == mem) {
+ found = true;
+ break;
+ }
+ }
+
+ if (!found)
+ return -ENOENT;
+
+ return tce_iommu_prereg_free(container, tcemem);
+}
+
+static long tce_iommu_register_pages(struct tce_container *container,
+ __u64 vaddr, __u64 size)
+{
+ long ret = 0;
+ struct mm_iommu_table_group_mem_t *mem = NULL;
+ struct tce_iommu_prereg *tcemem;
+ unsigned long entries = size >> PAGE_SHIFT;
+
+ if ((vaddr & ~PAGE_MASK) || (size & ~PAGE_MASK) ||
+ ((vaddr + size) < vaddr))
+ return -EINVAL;
+
+ mem = mm_iommu_find(container->mm, vaddr, entries);
+ if (mem) {
+ list_for_each_entry(tcemem, &container->prereg_list, next) {
+ if (tcemem->mem == mem)
+ return -EBUSY;
+ }
+ }
+
+ ret = mm_iommu_get(container->mm, vaddr, entries, &mem);
+ if (ret)
+ return ret;
+
+ tcemem = kzalloc(sizeof(*tcemem), GFP_KERNEL);
+ if (!tcemem) {
+ mm_iommu_put(container->mm, mem);
+ return -ENOMEM;
+ }
+
+ tcemem->mem = mem;
+ list_add(&tcemem->next, &container->prereg_list);
+
+ container->enabled = true;
+
+ return 0;
+}
+
+static bool tce_page_is_contained(struct page *page, unsigned page_shift)
+{
+ /*
+ * Check that the TCE table granularity is not bigger than the size of
+ * a page we just found. Otherwise the hardware can get access to
+ * a bigger memory chunk that it should.
+ */
+ return (PAGE_SHIFT + compound_order(compound_head(page))) >= page_shift;
+}
+
+static inline bool tce_groups_attached(struct tce_container *container)
+{
+ return !list_empty(&container->group_list);
+}
+
+static long tce_iommu_find_table(struct tce_container *container,
+ phys_addr_t ioba, struct iommu_table **ptbl)
+{
+ long i;
+
+ for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
+ struct iommu_table *tbl = container->tables[i];
+
+ if (tbl) {
+ 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)) {
+ *ptbl = tbl;
+ return i;
+ }
+ }
+ }
+
+ return -1;
+}
+
+static int tce_iommu_find_free_table(struct tce_container *container)
+{
+ int i;
+
+ for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
+ if (!container->tables[i])
+ return i;
+ }
+
+ return -ENOSPC;
+}
+
+static int tce_iommu_enable(struct tce_container *container)
+{
+ int ret = 0;
+ unsigned long locked;
+ struct iommu_table_group *table_group;
+ struct tce_iommu_group *tcegrp;
+
+ if (container->enabled)
+ return -EBUSY;
+
+ /*
+ * When userspace pages are mapped into the IOMMU, they are effectively
+ * locked memory, so, theoretically, we need to update the accounting
+ * of locked pages on each map and unmap. For powerpc, the map unmap
+ * paths can be very hot, though, and the accounting would kill
+ * performance, especially since it would be difficult to impossible
+ * to handle the accounting in real mode only.
+ *
+ * To address that, rather than precisely accounting every page, we
+ * instead account for a worst case on locked memory when the iommu is
+ * enabled and disabled. The worst case upper bound on locked memory
+ * is the size of the whole iommu window, which is usually relatively
+ * small (compared to total memory sizes) on POWER hardware.
+ *
+ * Also we don't have a nice way to fail on H_PUT_TCE due to ulimits,
+ * that would effectively kill the guest at random points, much better
+ * enforcing the limit based on the max that the guest can map.
+ *
+ * Unfortunately at the moment it counts whole tables, no matter how
+ * much memory the guest has. I.e. for 4GB guest and 4 IOMMU groups
+ * each with 2GB DMA window, 8GB will be counted here. The reason for
+ * 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.
+ */
+ if (!tce_groups_attached(container))
+ return -ENODEV;
+
+ tcegrp = list_first_entry(&container->group_list,
+ struct tce_iommu_group, next);
+ table_group = iommu_group_get_iommudata(tcegrp->grp);
+ if (!table_group)
+ return -ENODEV;
+
+ if (!table_group->tce32_size)
+ return -EPERM;
+
+ ret = tce_iommu_mm_set(container);
+ if (ret)
+ return ret;
+
+ locked = table_group->tce32_size >> PAGE_SHIFT;
+ ret = try_increment_locked_vm(container->mm, locked);
+ if (ret)
+ return ret;
+
+ container->locked_pages = locked;
+
+ container->enabled = true;
+
+ return ret;
+}
+
+static void tce_iommu_disable(struct tce_container *container)
+{
+ if (!container->enabled)
+ return;
+
+ container->enabled = false;
+
+ BUG_ON(!container->mm);
+ decrement_locked_vm(container->mm, container->locked_pages);
+}
+
+static void *tce_iommu_open(unsigned long arg)
+{
+ struct tce_container *container;
+
+ if ((arg != VFIO_SPAPR_TCE_IOMMU) && (arg != VFIO_SPAPR_TCE_v2_IOMMU)) {
+ pr_err("tce_vfio: Wrong IOMMU type\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ container = kzalloc(sizeof(*container), GFP_KERNEL);
+ if (!container)
+ return ERR_PTR(-ENOMEM);
+
+ mutex_init(&container->lock);
+ INIT_LIST_HEAD_RCU(&container->group_list);
+ INIT_LIST_HEAD_RCU(&container->prereg_list);
+
+ container->v2 = arg == VFIO_SPAPR_TCE_v2_IOMMU;
+
+ return container;
+}
+
+static int tce_iommu_clear(struct tce_container *container,
+ struct iommu_table *tbl,
+ unsigned long entry, unsigned long pages);
+static void tce_iommu_free_table(struct tce_container *container,
+ struct iommu_table *tbl);
+
+static void tce_iommu_release(void *iommu_data)
+{
+ struct tce_container *container = iommu_data;
+ struct tce_iommu_group *tcegrp;
+ struct tce_iommu_prereg *tcemem, *tmtmp;
+ long i;
+
+ while (tce_groups_attached(container)) {
+ tcegrp = list_first_entry(&container->group_list,
+ struct tce_iommu_group, next);
+ tce_iommu_detach_group(iommu_data, tcegrp->grp);
+ }
+
+ /*
+ * If VFIO created a table, it was not disposed
+ * by tce_iommu_detach_group() so do it now.
+ */
+ for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
+ struct iommu_table *tbl = container->tables[i];
+
+ if (!tbl)
+ continue;
+
+ tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
+ tce_iommu_free_table(container, tbl);
+ }
+
+ list_for_each_entry_safe(tcemem, tmtmp, &container->prereg_list, next)
+ WARN_ON(tce_iommu_prereg_free(container, tcemem));
+
+ tce_iommu_disable(container);
+ if (container->mm)
+ mmdrop(container->mm);
+ mutex_destroy(&container->lock);
+
+ kfree(container);
+}
+
+static void tce_iommu_unuse_page(struct tce_container *container,
+ unsigned long hpa)
+{
+ struct page *page;
+
+ page = pfn_to_page(hpa >> PAGE_SHIFT);
+ put_page(page);
+}
+
+static int tce_iommu_prereg_ua_to_hpa(struct tce_container *container,
+ unsigned long tce, unsigned long shift,
+ unsigned long *phpa, struct mm_iommu_table_group_mem_t **pmem)
+{
+ long ret = 0;
+ struct mm_iommu_table_group_mem_t *mem;
+
+ mem = mm_iommu_lookup(container->mm, tce, 1ULL << shift);
+ if (!mem)
+ return -EINVAL;
+
+ ret = mm_iommu_ua_to_hpa(mem, tce, shift, phpa);
+ if (ret)
+ return -EINVAL;
+
+ *pmem = mem;
+
+ return 0;
+}
+
+static void tce_iommu_unuse_page_v2(struct tce_container *container,
+ struct iommu_table *tbl, unsigned long entry)
+{
+ struct mm_iommu_table_group_mem_t *mem = NULL;
+ int ret;
+ unsigned long hpa = 0;
+ __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry);
+
+ if (!pua)
+ return;
+
+ ret = tce_iommu_prereg_ua_to_hpa(container, be64_to_cpu(*pua),
+ tbl->it_page_shift, &hpa, &mem);
+ if (ret)
+ pr_debug("%s: tce %llx at #%lx was not cached, ret=%d\n",
+ __func__, be64_to_cpu(*pua), entry, ret);
+ if (mem)
+ mm_iommu_mapped_dec(mem);
+
+ *pua = cpu_to_be64(0);
+}
+
+static int tce_iommu_clear(struct tce_container *container,
+ struct iommu_table *tbl,
+ unsigned long entry, unsigned long pages)
+{
+ unsigned long oldhpa;
+ long ret;
+ enum dma_data_direction direction;
+
+ for ( ; pages; --pages, ++entry) {
+ cond_resched();
+
+ direction = DMA_NONE;
+ oldhpa = 0;
+ ret = iommu_tce_xchg(tbl, entry, &oldhpa, &direction);
+ if (ret)
+ continue;
+
+ if (direction == DMA_NONE)
+ continue;
+
+ if (container->v2) {
+ tce_iommu_unuse_page_v2(container, tbl, entry);
+ continue;
+ }
+
+ tce_iommu_unuse_page(container, oldhpa);
+ }
+
+ return 0;
+}
+
+static int tce_iommu_use_page(unsigned long tce, unsigned long *hpa)
+{
+ struct page *page = NULL;
+ enum dma_data_direction direction = iommu_tce_direction(tce);
+
+ if (get_user_pages_fast(tce & PAGE_MASK, 1,
+ direction != DMA_TO_DEVICE, &page) != 1)
+ return -EFAULT;
+
+ *hpa = __pa((unsigned long) page_address(page));
+
+ return 0;
+}
+
+static long tce_iommu_build(struct tce_container *container,
+ struct iommu_table *tbl,
+ 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 dirtmp;
+
+ for (i = 0; i < pages; ++i) {
+ unsigned long offset = tce & IOMMU_PAGE_MASK(tbl) & ~PAGE_MASK;
+
+ ret = tce_iommu_use_page(tce, &hpa);
+ if (ret)
+ break;
+
+ page = pfn_to_page(hpa >> PAGE_SHIFT);
+ if (!tce_page_is_contained(page, tbl->it_page_shift)) {
+ ret = -EPERM;
+ break;
+ }
+
+ hpa |= offset;
+ 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",
+ __func__, entry << tbl->it_page_shift,
+ tce, ret);
+ break;
+ }
+
+ if (dirtmp != DMA_NONE)
+ tce_iommu_unuse_page(container, hpa);
+
+ tce += IOMMU_PAGE_SIZE(tbl);
+ }
+
+ if (ret)
+ tce_iommu_clear(container, tbl, entry, i);
+
+ return ret;
+}
+
+static long tce_iommu_build_v2(struct tce_container *container,
+ struct iommu_table *tbl,
+ 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 dirtmp;
+
+ for (i = 0; i < pages; ++i) {
+ struct mm_iommu_table_group_mem_t *mem = NULL;
+ __be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry + i);
+
+ ret = tce_iommu_prereg_ua_to_hpa(container,
+ tce, tbl->it_page_shift, &hpa, &mem);
+ if (ret)
+ break;
+
+ page = pfn_to_page(hpa >> PAGE_SHIFT);
+ if (!tce_page_is_contained(page, tbl->it_page_shift)) {
+ ret = -EPERM;
+ break;
+ }
+
+ /* Preserve offset within IOMMU page */
+ hpa |= tce & IOMMU_PAGE_MASK(tbl) & ~PAGE_MASK;
+ dirtmp = direction;
+
+ /* The registered region is being unregistered */
+ if (mm_iommu_mapped_inc(mem))
+ break;
+
+ ret = iommu_tce_xchg(tbl, entry + i, &hpa, &dirtmp);
+ if (ret) {
+ /* dirtmp cannot be DMA_NONE here */
+ tce_iommu_unuse_page_v2(container, tbl, entry + i);
+ pr_err("iommu_tce: %s failed ioba=%lx, tce=%lx, ret=%ld\n",
+ __func__, entry << tbl->it_page_shift,
+ tce, ret);
+ break;
+ }
+
+ if (dirtmp != DMA_NONE)
+ tce_iommu_unuse_page_v2(container, tbl, entry + i);
+
+ *pua = cpu_to_be64(tce);
+
+ tce += IOMMU_PAGE_SIZE(tbl);
+ }
+
+ if (ret)
+ tce_iommu_clear(container, tbl, entry, i);
+
+ return ret;
+}
+
+static long tce_iommu_create_table(struct tce_container *container,
+ struct iommu_table_group *table_group,
+ int num,
+ __u32 page_shift,
+ __u64 window_size,
+ __u32 levels,
+ struct iommu_table **ptbl)
+{
+ long ret, table_size;
+
+ table_size = table_group->ops->get_table_size(page_shift, window_size,
+ levels);
+ if (!table_size)
+ return -EINVAL;
+
+ ret = try_increment_locked_vm(container->mm, table_size >> PAGE_SHIFT);
+ if (ret)
+ return ret;
+
+ ret = table_group->ops->create_table(table_group, num,
+ page_shift, window_size, levels, ptbl);
+
+ WARN_ON(!ret && !(*ptbl)->it_ops->free);
+ WARN_ON(!ret && ((*ptbl)->it_allocated_size > table_size));
+
+ return ret;
+}
+
+static void tce_iommu_free_table(struct tce_container *container,
+ struct iommu_table *tbl)
+{
+ unsigned long pages = tbl->it_allocated_size >> PAGE_SHIFT;
+
+ iommu_tce_table_put(tbl);
+ decrement_locked_vm(container->mm, pages);
+}
+
+static long tce_iommu_create_window(struct tce_container *container,
+ __u32 page_shift, __u64 window_size, __u32 levels,
+ __u64 *start_addr)
+{
+ struct tce_iommu_group *tcegrp;
+ struct iommu_table_group *table_group;
+ struct iommu_table *tbl = NULL;
+ long ret, num;
+
+ num = tce_iommu_find_free_table(container);
+ if (num < 0)
+ return num;
+
+ /* Get the first group for ops::create_table */
+ tcegrp = list_first_entry(&container->group_list,
+ struct tce_iommu_group, next);
+ table_group = iommu_group_get_iommudata(tcegrp->grp);
+ if (!table_group)
+ return -EFAULT;
+
+ if (!(table_group->pgsizes & (1ULL << page_shift)))
+ return -EINVAL;
+
+ if (!table_group->ops->set_window || !table_group->ops->unset_window ||
+ !table_group->ops->get_table_size ||
+ !table_group->ops->create_table)
+ return -EPERM;
+
+ /* Create TCE table */
+ ret = tce_iommu_create_table(container, table_group, num,
+ page_shift, window_size, levels, &tbl);
+ if (ret)
+ return ret;
+
+ BUG_ON(!tbl->it_ops->free);
+
+ /*
+ * Program the table to every group.
+ * Groups have been tested for compatibility at the attach time.
+ */
+ list_for_each_entry(tcegrp, &container->group_list, next) {
+ table_group = iommu_group_get_iommudata(tcegrp->grp);
+
+ ret = table_group->ops->set_window(table_group, num, tbl);
+ if (ret)
+ goto unset_exit;
+ }
+
+ container->tables[num] = tbl;
+
+ /* Return start address assigned by platform in create_table() */
+ *start_addr = tbl->it_offset << tbl->it_page_shift;
+
+ return 0;
+
+unset_exit:
+ list_for_each_entry(tcegrp, &container->group_list, next) {
+ table_group = iommu_group_get_iommudata(tcegrp->grp);
+ table_group->ops->unset_window(table_group, num);
+ }
+ tce_iommu_free_table(container, tbl);
+
+ return ret;
+}
+
+static long tce_iommu_remove_window(struct tce_container *container,
+ __u64 start_addr)
+{
+ struct iommu_table_group *table_group = NULL;
+ struct iommu_table *tbl;
+ struct tce_iommu_group *tcegrp;
+ int num;
+
+ num = tce_iommu_find_table(container, start_addr, &tbl);
+ if (num < 0)
+ return -EINVAL;
+
+ BUG_ON(!tbl->it_size);
+
+ /* Detach groups from IOMMUs */
+ list_for_each_entry(tcegrp, &container->group_list, next) {
+ table_group = iommu_group_get_iommudata(tcegrp->grp);
+
+ /*
+ * SPAPR TCE IOMMU exposes the default DMA window to
+ * the guest via dma32_window_start/size of
+ * VFIO_IOMMU_SPAPR_TCE_GET_INFO. Some platforms allow
+ * the userspace to remove this window, some do not so
+ * here we check for the platform capability.
+ */
+ if (!table_group->ops || !table_group->ops->unset_window)
+ return -EPERM;
+
+ table_group->ops->unset_window(table_group, num);
+ }
+
+ /* Free table */
+ tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
+ tce_iommu_free_table(container, tbl);
+ container->tables[num] = NULL;
+
+ return 0;
+}
+
+static long tce_iommu_create_default_window(struct tce_container *container)
+{
+ long ret;
+ __u64 start_addr = 0;
+ struct tce_iommu_group *tcegrp;
+ struct iommu_table_group *table_group;
+
+ if (!container->def_window_pending)
+ return 0;
+
+ if (!tce_groups_attached(container))
+ return -ENODEV;
+
+ tcegrp = list_first_entry(&container->group_list,
+ struct tce_iommu_group, next);
+ table_group = iommu_group_get_iommudata(tcegrp->grp);
+ if (!table_group)
+ return -ENODEV;
+
+ ret = tce_iommu_create_window(container, IOMMU_PAGE_SHIFT_4K,
+ table_group->tce32_size, 1, &start_addr);
+ WARN_ON_ONCE(!ret && start_addr);
+
+ if (!ret)
+ container->def_window_pending = false;
+
+ return ret;
+}
+
+static long tce_iommu_ioctl(void *iommu_data,
+ unsigned int cmd, unsigned long arg)
+{
+ struct tce_container *container = iommu_data;
+ unsigned long minsz, ddwsz;
+ long ret;
+
+ switch (cmd) {
+ case VFIO_CHECK_EXTENSION:
+ switch (arg) {
+ case VFIO_SPAPR_TCE_IOMMU:
+ case VFIO_SPAPR_TCE_v2_IOMMU:
+ ret = 1;
+ break;
+ default:
+ ret = vfio_spapr_iommu_eeh_ioctl(NULL, cmd, arg);
+ break;
+ }
+
+ return (ret < 0) ? 0 : ret;
+ }
+
+ /*
+ * Sanity check to prevent one userspace from manipulating
+ * another userspace mm.
+ */
+ BUG_ON(!container);
+ if (container->mm && container->mm != current->mm)
+ return -EPERM;
+
+ switch (cmd) {
+ case VFIO_IOMMU_SPAPR_TCE_GET_INFO: {
+ struct vfio_iommu_spapr_tce_info info;
+ struct tce_iommu_group *tcegrp;
+ struct iommu_table_group *table_group;
+
+ if (!tce_groups_attached(container))
+ return -ENXIO;
+
+ tcegrp = list_first_entry(&container->group_list,
+ struct tce_iommu_group, next);
+ table_group = iommu_group_get_iommudata(tcegrp->grp);
+
+ if (!table_group)
+ return -ENXIO;
+
+ minsz = offsetofend(struct vfio_iommu_spapr_tce_info,
+ dma32_window_size);
+
+ if (copy_from_user(&info, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (info.argsz < minsz)
+ return -EINVAL;
+
+ info.dma32_window_start = table_group->tce32_start;
+ info.dma32_window_size = table_group->tce32_size;
+ info.flags = 0;
+ memset(&info.ddw, 0, sizeof(info.ddw));
+
+ if (table_group->max_dynamic_windows_supported &&
+ container->v2) {
+ info.flags |= VFIO_IOMMU_SPAPR_INFO_DDW;
+ info.ddw.pgsizes = table_group->pgsizes;
+ info.ddw.max_dynamic_windows_supported =
+ table_group->max_dynamic_windows_supported;
+ info.ddw.levels = table_group->max_levels;
+ }
+
+ ddwsz = offsetofend(struct vfio_iommu_spapr_tce_info, ddw);
+
+ if (info.argsz >= ddwsz)
+ minsz = ddwsz;
+
+ if (copy_to_user((void __user *)arg, &info, minsz))
+ return -EFAULT;
+
+ return 0;
+ }
+ case VFIO_IOMMU_MAP_DMA: {
+ struct vfio_iommu_type1_dma_map param;
+ struct iommu_table *tbl = NULL;
+ long num;
+ enum dma_data_direction direction;
+
+ if (!container->enabled)
+ return -EPERM;
+
+ minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);
+
+ if (copy_from_user(&param, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (param.argsz < minsz)
+ return -EINVAL;
+
+ if (param.flags & ~(VFIO_DMA_MAP_FLAG_READ |
+ VFIO_DMA_MAP_FLAG_WRITE))
+ return -EINVAL;
+
+ ret = tce_iommu_create_default_window(container);
+ if (ret)
+ return ret;
+
+ num = tce_iommu_find_table(container, param.iova, &tbl);
+ if (num < 0)
+ return -ENXIO;
+
+ if ((param.size & ~IOMMU_PAGE_MASK(tbl)) ||
+ (param.vaddr & ~IOMMU_PAGE_MASK(tbl)))
+ return -EINVAL;
+
+ /* iova is checked by the IOMMU API */
+ 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, param.vaddr);
+ if (ret)
+ return ret;
+
+ if (container->v2)
+ ret = tce_iommu_build_v2(container, tbl,
+ param.iova >> tbl->it_page_shift,
+ param.vaddr,
+ param.size >> tbl->it_page_shift,
+ direction);
+ else
+ ret = tce_iommu_build(container, tbl,
+ param.iova >> tbl->it_page_shift,
+ param.vaddr,
+ param.size >> tbl->it_page_shift,
+ direction);
+
+ iommu_flush_tce(tbl);
+
+ return ret;
+ }
+ case VFIO_IOMMU_UNMAP_DMA: {
+ struct vfio_iommu_type1_dma_unmap param;
+ struct iommu_table *tbl = NULL;
+ long num;
+
+ if (!container->enabled)
+ return -EPERM;
+
+ minsz = offsetofend(struct vfio_iommu_type1_dma_unmap,
+ size);
+
+ if (copy_from_user(&param, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (param.argsz < minsz)
+ return -EINVAL;
+
+ /* No flag is supported now */
+ if (param.flags)
+ return -EINVAL;
+
+ ret = tce_iommu_create_default_window(container);
+ if (ret)
+ return ret;
+
+ num = tce_iommu_find_table(container, param.iova, &tbl);
+ if (num < 0)
+ return -ENXIO;
+
+ if (param.size & ~IOMMU_PAGE_MASK(tbl))
+ return -EINVAL;
+
+ ret = iommu_tce_clear_param_check(tbl, param.iova, 0,
+ param.size >> tbl->it_page_shift);
+ if (ret)
+ return ret;
+
+ ret = tce_iommu_clear(container, tbl,
+ param.iova >> tbl->it_page_shift,
+ param.size >> tbl->it_page_shift);
+ iommu_flush_tce(tbl);
+
+ return ret;
+ }
+ case VFIO_IOMMU_SPAPR_REGISTER_MEMORY: {
+ struct vfio_iommu_spapr_register_memory param;
+
+ if (!container->v2)
+ break;
+
+ minsz = offsetofend(struct vfio_iommu_spapr_register_memory,
+ size);
+
+ ret = tce_iommu_mm_set(container);
+ if (ret)
+ return ret;
+
+ if (copy_from_user(&param, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (param.argsz < minsz)
+ return -EINVAL;
+
+ /* No flag is supported now */
+ if (param.flags)
+ return -EINVAL;
+
+ mutex_lock(&container->lock);
+ ret = tce_iommu_register_pages(container, param.vaddr,
+ param.size);
+ mutex_unlock(&container->lock);
+
+ return ret;
+ }
+ case VFIO_IOMMU_SPAPR_UNREGISTER_MEMORY: {
+ struct vfio_iommu_spapr_register_memory param;
+
+ if (!container->v2)
+ break;
+
+ if (!container->mm)
+ return -EPERM;
+
+ minsz = offsetofend(struct vfio_iommu_spapr_register_memory,
+ size);
+
+ if (copy_from_user(&param, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (param.argsz < minsz)
+ return -EINVAL;
+
+ /* No flag is supported now */
+ if (param.flags)
+ return -EINVAL;
+
+ mutex_lock(&container->lock);
+ ret = tce_iommu_unregister_pages(container, param.vaddr,
+ param.size);
+ mutex_unlock(&container->lock);
+
+ return ret;
+ }
+ case VFIO_IOMMU_ENABLE:
+ if (container->v2)
+ break;
+
+ mutex_lock(&container->lock);
+ ret = tce_iommu_enable(container);
+ mutex_unlock(&container->lock);
+ return ret;
+
+
+ case VFIO_IOMMU_DISABLE:
+ if (container->v2)
+ break;
+
+ mutex_lock(&container->lock);
+ tce_iommu_disable(container);
+ mutex_unlock(&container->lock);
+ return 0;
+
+ case VFIO_EEH_PE_OP: {
+ struct tce_iommu_group *tcegrp;
+
+ ret = 0;
+ list_for_each_entry(tcegrp, &container->group_list, next) {
+ ret = vfio_spapr_iommu_eeh_ioctl(tcegrp->grp,
+ cmd, arg);
+ if (ret)
+ return ret;
+ }
+ return ret;
+ }
+
+ case VFIO_IOMMU_SPAPR_TCE_CREATE: {
+ struct vfio_iommu_spapr_tce_create create;
+
+ if (!container->v2)
+ break;
+
+ ret = tce_iommu_mm_set(container);
+ if (ret)
+ return ret;
+
+ if (!tce_groups_attached(container))
+ return -ENXIO;
+
+ minsz = offsetofend(struct vfio_iommu_spapr_tce_create,
+ start_addr);
+
+ if (copy_from_user(&create, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (create.argsz < minsz)
+ return -EINVAL;
+
+ if (create.flags)
+ return -EINVAL;
+
+ mutex_lock(&container->lock);
+
+ ret = tce_iommu_create_default_window(container);
+ if (!ret)
+ ret = tce_iommu_create_window(container,
+ create.page_shift,
+ create.window_size, create.levels,
+ &create.start_addr);
+
+ mutex_unlock(&container->lock);
+
+ if (!ret && copy_to_user((void __user *)arg, &create, minsz))
+ ret = -EFAULT;
+
+ return ret;
+ }
+ case VFIO_IOMMU_SPAPR_TCE_REMOVE: {
+ struct vfio_iommu_spapr_tce_remove remove;
+
+ if (!container->v2)
+ break;
+
+ ret = tce_iommu_mm_set(container);
+ if (ret)
+ return ret;
+
+ if (!tce_groups_attached(container))
+ return -ENXIO;
+
+ minsz = offsetofend(struct vfio_iommu_spapr_tce_remove,
+ start_addr);
+
+ if (copy_from_user(&remove, (void __user *)arg, minsz))
+ return -EFAULT;
+
+ if (remove.argsz < minsz)
+ return -EINVAL;
+
+ if (remove.flags)
+ return -EINVAL;
+
+ if (container->def_window_pending && !remove.start_addr) {
+ container->def_window_pending = false;
+ return 0;
+ }
+
+ mutex_lock(&container->lock);
+
+ ret = tce_iommu_remove_window(container, remove.start_addr);
+
+ mutex_unlock(&container->lock);
+
+ return ret;
+ }
+ }
+
+ return -ENOTTY;
+}
+
+static void tce_iommu_release_ownership(struct tce_container *container,
+ struct iommu_table_group *table_group)
+{
+ int i;
+
+ for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
+ struct iommu_table *tbl = container->tables[i];
+
+ if (!tbl)
+ continue;
+
+ tce_iommu_clear(container, tbl, tbl->it_offset, tbl->it_size);
+ if (tbl->it_map)
+ iommu_release_ownership(tbl);
+
+ container->tables[i] = NULL;
+ }
+}
+
+static int tce_iommu_take_ownership(struct tce_container *container,
+ struct iommu_table_group *table_group)
+{
+ int i, j, rc = 0;
+
+ for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
+ struct iommu_table *tbl = table_group->tables[i];
+
+ if (!tbl || !tbl->it_map)
+ continue;
+
+ rc = iommu_take_ownership(tbl);
+ if (rc) {
+ for (j = 0; j < i; ++j)
+ iommu_release_ownership(
+ table_group->tables[j]);
+
+ return rc;
+ }
+ }
+
+ for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i)
+ container->tables[i] = table_group->tables[i];
+
+ return 0;
+}
+
+static void tce_iommu_release_ownership_ddw(struct tce_container *container,
+ struct iommu_table_group *table_group)
+{
+ long i;
+
+ if (!table_group->ops->unset_window) {
+ WARN_ON_ONCE(1);
+ return;
+ }
+
+ for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i)
+ table_group->ops->unset_window(table_group, i);
+
+ table_group->ops->release_ownership(table_group);
+}
+
+static long tce_iommu_take_ownership_ddw(struct tce_container *container,
+ struct iommu_table_group *table_group)
+{
+ long i, ret = 0;
+
+ if (!table_group->ops->create_table || !table_group->ops->set_window ||
+ !table_group->ops->release_ownership) {
+ WARN_ON_ONCE(1);
+ return -EFAULT;
+ }
+
+ table_group->ops->take_ownership(table_group);
+
+ /* Set all windows to the new group */
+ for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
+ struct iommu_table *tbl = container->tables[i];
+
+ if (!tbl)
+ continue;
+
+ ret = table_group->ops->set_window(table_group, i, tbl);
+ if (ret)
+ goto release_exit;
+ }
+
+ return 0;
+
+release_exit:
+ for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i)
+ table_group->ops->unset_window(table_group, i);
+
+ table_group->ops->release_ownership(table_group);
+
+ return ret;
+}
+
+static int tce_iommu_attach_group(void *iommu_data,
+ struct iommu_group *iommu_group)
+{
+ int ret;
+ struct tce_container *container = iommu_data;
+ struct iommu_table_group *table_group;
+ struct tce_iommu_group *tcegrp = NULL;
+
+ mutex_lock(&container->lock);
+
+ /* pr_debug("tce_vfio: Attaching group #%u to iommu %p\n",
+ iommu_group_id(iommu_group), iommu_group); */
+ table_group = iommu_group_get_iommudata(iommu_group);
+ if (!table_group) {
+ ret = -ENODEV;
+ goto unlock_exit;
+ }
+
+ if (tce_groups_attached(container) && (!table_group->ops ||
+ !table_group->ops->take_ownership ||
+ !table_group->ops->release_ownership)) {
+ ret = -EBUSY;
+ goto unlock_exit;
+ }
+
+ /* Check if new group has the same iommu_ops (i.e. compatible) */
+ list_for_each_entry(tcegrp, &container->group_list, next) {
+ struct iommu_table_group *table_group_tmp;
+
+ if (tcegrp->grp == iommu_group) {
+ pr_warn("tce_vfio: Group %d is already attached\n",
+ iommu_group_id(iommu_group));
+ ret = -EBUSY;
+ goto unlock_exit;
+ }
+ table_group_tmp = iommu_group_get_iommudata(tcegrp->grp);
+ if (table_group_tmp->ops->create_table !=
+ table_group->ops->create_table) {
+ pr_warn("tce_vfio: Group %d is incompatible with group %d\n",
+ iommu_group_id(iommu_group),
+ iommu_group_id(tcegrp->grp));
+ ret = -EPERM;
+ goto unlock_exit;
+ }
+ }
+
+ tcegrp = kzalloc(sizeof(*tcegrp), GFP_KERNEL);
+ if (!tcegrp) {
+ ret = -ENOMEM;
+ goto unlock_exit;
+ }
+
+ if (!table_group->ops || !table_group->ops->take_ownership ||
+ !table_group->ops->release_ownership) {
+ if (container->v2) {
+ ret = -EPERM;
+ goto unlock_exit;
+ }
+ ret = tce_iommu_take_ownership(container, table_group);
+ } else {
+ if (!container->v2) {
+ ret = -EPERM;
+ goto unlock_exit;
+ }
+ ret = tce_iommu_take_ownership_ddw(container, table_group);
+ if (!tce_groups_attached(container) && !container->tables[0])
+ container->def_window_pending = true;
+ }
+
+ if (!ret) {
+ tcegrp->grp = iommu_group;
+ list_add(&tcegrp->next, &container->group_list);
+ }
+
+unlock_exit:
+ if (ret && tcegrp)
+ kfree(tcegrp);
+
+ mutex_unlock(&container->lock);
+
+ return ret;
+}
+
+static void tce_iommu_detach_group(void *iommu_data,
+ struct iommu_group *iommu_group)
+{
+ struct tce_container *container = iommu_data;
+ struct iommu_table_group *table_group;
+ bool found = false;
+ struct tce_iommu_group *tcegrp;
+
+ mutex_lock(&container->lock);
+
+ list_for_each_entry(tcegrp, &container->group_list, next) {
+ if (tcegrp->grp == iommu_group) {
+ found = true;
+ break;
+ }
+ }
+
+ if (!found) {
+ pr_warn("tce_vfio: detaching unattached group #%u\n",
+ iommu_group_id(iommu_group));
+ goto unlock_exit;
+ }
+
+ list_del(&tcegrp->next);
+ kfree(tcegrp);
+
+ table_group = iommu_group_get_iommudata(iommu_group);
+ BUG_ON(!table_group);
+
+ if (!table_group->ops || !table_group->ops->release_ownership)
+ tce_iommu_release_ownership(container, table_group);
+ else
+ tce_iommu_release_ownership_ddw(container, table_group);
+
+unlock_exit:
+ mutex_unlock(&container->lock);
+}
+
+const struct vfio_iommu_driver_ops tce_iommu_driver_ops = {
+ .name = "iommu-vfio-powerpc",
+ .owner = THIS_MODULE,
+ .open = tce_iommu_open,
+ .release = tce_iommu_release,
+ .ioctl = tce_iommu_ioctl,
+ .attach_group = tce_iommu_attach_group,
+ .detach_group = tce_iommu_detach_group,
+};
+
+static int __init tce_iommu_init(void)
+{
+ return vfio_register_iommu_driver(&tce_iommu_driver_ops);
+}
+
+static void __exit tce_iommu_cleanup(void)
+{
+ vfio_unregister_iommu_driver(&tce_iommu_driver_ops);
+}
+
+module_init(tce_iommu_init);
+module_exit(tce_iommu_cleanup);
+
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-30 12:39:19 +0000