linux-stable/drivers/vfio/vfio_iommu_spapr_tce.c
Ira Weiny 73b0140bf0 mm/gup: change GUP fast to use flags rather than a write 'bool'
To facilitate additional options to get_user_pages_fast() change the
singular write parameter to be gup_flags.

This patch does not change any functionality.  New functionality will
follow in subsequent patches.

Some of the get_user_pages_fast() call sites were unchanged because they
already passed FOLL_WRITE or 0 for the write parameter.

NOTE: It was suggested to change the ordering of the get_user_pages_fast()
arguments to ensure that callers were converted.  This breaks the current
GUP call site convention of having the returned pages be the final
parameter.  So the suggestion was rejected.

Link: http://lkml.kernel.org/r/20190328084422.29911-4-ira.weiny@intel.com
Link: http://lkml.kernel.org/r/20190317183438.2057-4-ira.weiny@intel.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Mike Marshall <hubcap@omnibond.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:46 -07:00

1429 lines
33 KiB
C

/*
* 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;
long ret;
if ((vaddr & ~PAGE_MASK) || (size & ~PAGE_MASK))
return -EINVAL;
mem = mm_iommu_get(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)
ret = -ENOENT;
else
ret = tce_iommu_prereg_free(container, tcemem);
mm_iommu_put(container->mm, mem);
return ret;
}
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_get(container->mm, vaddr, entries);
if (mem) {
list_for_each_entry(tcemem, &container->prereg_list, next) {
if (tcemem->mem == mem) {
ret = -EBUSY;
goto put_exit;
}
}
} else {
ret = mm_iommu_new(container->mm, vaddr, entries, &mem);
if (ret)
return ret;
}
tcemem = kzalloc(sizeof(*tcemem), GFP_KERNEL);
if (!tcemem) {
ret = -ENOMEM;
goto put_exit;
}
tcemem->mem = mem;
list_add(&tcemem->next, &container->prereg_list);
container->enabled = true;
return 0;
put_exit:
mm_iommu_put(container->mm, mem);
return ret;
}
static bool tce_page_is_contained(struct mm_struct *mm, unsigned long hpa,
unsigned int page_shift)
{
struct page *page;
unsigned long size = 0;
if (mm_iommu_is_devmem(mm, hpa, page_shift, &size))
return size == (1UL << page_shift);
page = pfn_to_page(hpa >> 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_RO(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;
unsigned long lastentry = entry + pages;
for ( ; entry < lastentry; ++entry) {
if (tbl->it_indirect_levels && tbl->it_userspace) {
/*
* For multilevel tables, we can take a shortcut here
* and skip some TCEs as we know that the userspace
* addresses cache is a mirror of the real TCE table
* and if it is missing some indirect levels, then
* the hardware table does not have them allocated
* either and therefore does not require updating.
*/
__be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY_RO(tbl,
entry);
if (!pua) {
/* align to level_size which is power of two */
entry |= tbl->it_level_size - 1;
continue;
}
}
cond_resched();
direction = DMA_NONE;
oldhpa = 0;
ret = iommu_tce_xchg(container->mm, 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 ? FOLL_WRITE : 0,
&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;
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;
if (!tce_page_is_contained(container->mm, hpa,
tbl->it_page_shift)) {
ret = -EPERM;
break;
}
hpa |= offset;
dirtmp = direction;
ret = iommu_tce_xchg(container->mm, 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;
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;
if (!tce_page_is_contained(container->mm, hpa,
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(container->mm, 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)
if (container->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);
}
static 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);