// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2021-2022, NVIDIA CORPORATION & AFFILIATES. All rights reserved
*/
#include <linux/device.h>
#include <linux/eventfd.h>
#include <linux/file.h>
#include <linux/interrupt.h>
#include <linux/iommu.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/notifier.h>
#include <linux/pci.h>
#include <linux/pm_runtime.h>
#include <linux/types.h>
#include <linux/uaccess.h>
#include <linux/vfio.h>
#include <linux/sched/mm.h>
#include <linux/anon_inodes.h>
#include "cmd.h"
/* Device specification max LOAD size */
#define MAX_LOAD_SIZE (BIT_ULL(__mlx5_bit_sz(load_vhca_state_in, size)) - 1)
static struct mlx5vf_pci_core_device *mlx5vf_drvdata(struct pci_dev *pdev)
{
struct vfio_pci_core_device *core_device = dev_get_drvdata(&pdev->dev);
return container_of(core_device, struct mlx5vf_pci_core_device,
core_device);
}
struct page *
mlx5vf_get_migration_page(struct mlx5_vhca_data_buffer *buf,
unsigned long offset)
{
unsigned long cur_offset = 0;
struct scatterlist *sg;
unsigned int i;
/* All accesses are sequential */
if (offset < buf->last_offset || !buf->last_offset_sg) {
buf->last_offset = 0;
buf->last_offset_sg = buf->table.sgt.sgl;
buf->sg_last_entry = 0;
}
cur_offset = buf->last_offset;
for_each_sg(buf->last_offset_sg, sg,
buf->table.sgt.orig_nents - buf->sg_last_entry, i) {
if (offset < sg->length + cur_offset) {
buf->last_offset_sg = sg;
buf->sg_last_entry += i;
buf->last_offset = cur_offset;
return nth_page(sg_page(sg),
(offset - cur_offset) / PAGE_SIZE);
}
cur_offset += sg->length;
}
return NULL;
}
int mlx5vf_add_migration_pages(struct mlx5_vhca_data_buffer *buf,
unsigned int npages)
{
unsigned int to_alloc = npages;
struct page **page_list;
unsigned long filled;
unsigned int to_fill;
int ret;
to_fill = min_t(unsigned int, npages, PAGE_SIZE / sizeof(*page_list));
page_list = kvzalloc(to_fill * sizeof(*page_list), GFP_KERNEL_ACCOUNT);
if (!page_list)
return -ENOMEM;
do {
filled = alloc_pages_bulk_array(GFP_KERNEL_ACCOUNT, to_fill,
page_list);
if (!filled) {
ret = -ENOMEM;
goto err;
}
to_alloc -= filled;
ret = sg_alloc_append_table_from_pages(
&buf->table, page_list, filled, 0,
filled << PAGE_SHIFT, UINT_MAX, SG_MAX_SINGLE_ALLOC,
GFP_KERNEL_ACCOUNT);
if (ret)
goto err;
buf->allocated_length += filled * PAGE_SIZE;
/* clean input for another bulk allocation */
memset(page_list, 0, filled * sizeof(*page_list));
to_fill = min_t(unsigned int, to_alloc,
PAGE_SIZE / sizeof(*page_list));
} while (to_alloc > 0);
kvfree(page_list);
return 0;
err:
kvfree(page_list);
return ret;
}
static void mlx5vf_disable_fd(struct mlx5_vf_migration_file *migf)
{
mutex_lock(&migf->lock);
migf->state = MLX5_MIGF_STATE_ERROR;
migf->filp->f_pos = 0;
mutex_unlock(&migf->lock);
}
static int mlx5vf_release_file(struct inode *inode, struct file *filp)
{
struct mlx5_vf_migration_file *migf = filp->private_data;
mlx5vf_disable_fd(migf);
mutex_destroy(&migf->lock);
kfree(migf);
return 0;
}
static struct mlx5_vhca_data_buffer *
mlx5vf_get_data_buff_from_pos(struct mlx5_vf_migration_file *migf, loff_t pos,
bool *end_of_data)
{
struct mlx5_vhca_data_buffer *buf;
bool found = false;
*end_of_data = false;
spin_lock_irq(&migf->list_lock);
if (list_empty(&migf->buf_list)) {
*end_of_data = true;
goto end;
}
buf = list_first_entry(&migf->buf_list, struct mlx5_vhca_data_buffer,
buf_elm);
if (pos >= buf->start_pos &&
pos < buf->start_pos + buf->length) {
found = true;
goto end;
}
/*
* As we use a stream based FD we may expect having the data always
* on first chunk
*/
migf->state = MLX5_MIGF_STATE_ERROR;
end:
spin_unlock_irq(&migf->list_lock);
return found ? buf : NULL;
}
static ssize_t mlx5vf_buf_read(struct mlx5_vhca_data_buffer *vhca_buf,
char __user **buf, size_t *len, loff_t *pos)
{
unsigned long offset;
ssize_t done = 0;
size_t copy_len;
copy_len = min_t(size_t,
vhca_buf->start_pos + vhca_buf->length - *pos, *len);
while (copy_len) {
size_t page_offset;
struct page *page;
size_t page_len;
u8 *from_buff;
int ret;
offset = *pos - vhca_buf->start_pos;
page_offset = offset % PAGE_SIZE;
offset -= page_offset;
page = mlx5vf_get_migration_page(vhca_buf, offset);
if (!page)
return -EINVAL;
page_len = min_t(size_t, copy_len, PAGE_SIZE - page_offset);
from_buff = kmap_local_page(page);
ret = copy_to_user(*buf, from_buff + page_offset, page_len);
kunmap_local(from_buff);
if (ret)
return -EFAULT;
*pos += page_len;
*len -= page_len;
*buf += page_len;
done += page_len;
copy_len -= page_len;
}
if (*pos >= vhca_buf->start_pos + vhca_buf->length) {
spin_lock_irq(&vhca_buf->migf->list_lock);
list_del_init(&vhca_buf->buf_elm);
list_add_tail(&vhca_buf->buf_elm, &vhca_buf->migf->avail_list);
spin_unlock_irq(&vhca_buf->migf->list_lock);
}
return done;
}
static ssize_t mlx5vf_save_read(struct file *filp, char __user *buf, size_t len,
loff_t *pos)
{
struct mlx5_vf_migration_file *migf = filp->private_data;
struct mlx5_vhca_data_buffer *vhca_buf;
bool first_loop_call = true;
bool end_of_data;
ssize_t done = 0;
if (pos)
return -ESPIPE;
pos = &filp->f_pos;
if (!(filp->f_flags & O_NONBLOCK)) {
if (wait_event_interruptible(migf->poll_wait,
!list_empty(&migf->buf_list) ||
migf->state == MLX5_MIGF_STATE_ERROR ||
migf->state == MLX5_MIGF_STATE_PRE_COPY_ERROR ||
migf->state == MLX5_MIGF_STATE_PRE_COPY ||
migf->state == MLX5_MIGF_STATE_COMPLETE))
return -ERESTARTSYS;
}
mutex_lock(&migf->lock);
if (migf->state == MLX5_MIGF_STATE_ERROR) {
done = -ENODEV;
goto out_unlock;
}
while (len) {
ssize_t count;
vhca_buf = mlx5vf_get_data_buff_from_pos(migf, *pos,
&end_of_data);
if (first_loop_call) {
first_loop_call = false;
/* Temporary end of file as part of PRE_COPY */
if (end_of_data && (migf->state == MLX5_MIGF_STATE_PRE_COPY ||
migf->state == MLX5_MIGF_STATE_PRE_COPY_ERROR)) {
done = -ENOMSG;
goto out_unlock;
}
if (end_of_data && migf->state != MLX5_MIGF_STATE_COMPLETE) {
if (filp->f_flags & O_NONBLOCK) {
done = -EAGAIN;
goto out_unlock;
}
}
}
if (end_of_data)
goto out_unlock;
if (!vhca_buf) {
done = -EINVAL;
goto out_unlock;
}
count = mlx5vf_buf_read(vhca_buf, &buf, &len, pos);
if (count < 0) {
done = count;
goto out_unlock;
}
done += count;
}
out_unlock:
mutex_unlock(&migf->lock);
return done;
}
static __poll_t mlx5vf_save_poll(struct file *filp,
struct poll_table_struct *wait)
{
struct mlx5_vf_migration_file *migf = filp->private_data;
__poll_t pollflags = 0;
poll_wait(filp, &migf->poll_wait, wait);
mutex_lock(&migf->lock);
if (migf->state == MLX5_MIGF_STATE_ERROR)
pollflags = EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
else if (!list_empty(&migf->buf_list) ||
migf->state == MLX5_MIGF_STATE_COMPLETE)
pollflags = EPOLLIN | EPOLLRDNORM;
mutex_unlock(&migf->lock);
return pollflags;
}
/*
* FD is exposed and user can use it after receiving an error.
* Mark migf in error, and wake the user.
*/
static void mlx5vf_mark_err(struct mlx5_vf_migration_file *migf)
{
migf->state = MLX5_MIGF_STATE_ERROR;
wake_up_interruptible(&migf->poll_wait);
}
static int mlx5vf_add_stop_copy_header(struct mlx5_vf_migration_file *migf)
{
size_t size = sizeof(struct mlx5_vf_migration_header) +
sizeof(struct mlx5_vf_migration_tag_stop_copy_data);
struct mlx5_vf_migration_tag_stop_copy_data data = {};
struct mlx5_vhca_data_buffer *header_buf = NULL;
struct mlx5_vf_migration_header header = {};
unsigned long flags;
struct page *page;
u8 *to_buff;
int ret;
header_buf = mlx5vf_get_data_buffer(migf, size, DMA_NONE);
if (IS_ERR(header_buf))
return PTR_ERR(header_buf);
header.record_size = cpu_to_le64(sizeof(data));
header.flags = cpu_to_le32(MLX5_MIGF_HEADER_FLAGS_TAG_OPTIONAL);
header.tag = cpu_to_le32(MLX5_MIGF_HEADER_TAG_STOP_COPY_SIZE);
page = mlx5vf_get_migration_page(header_buf, 0);
if (!page) {
ret = -EINVAL;
goto err;
}
to_buff = kmap_local_page(page);
memcpy(to_buff, &header, sizeof(header));
header_buf->length = sizeof(header);
data.stop_copy_size = cpu_to_le64(migf->buf->allocated_length);
memcpy(to_buff + sizeof(header), &data, sizeof(data));
header_buf->length += sizeof(data);
kunmap_local(to_buff);
header_buf->start_pos = header_buf->migf->max_pos;
migf->max_pos += header_buf->length;
spin_lock_irqsave(&migf->list_lock, flags);
list_add_tail(&header_buf->buf_elm, &migf->buf_list);
spin_unlock_irqrestore(&migf->list_lock, flags);
migf->pre_copy_initial_bytes = size;
return 0;
err:
mlx5vf_put_data_buffer(header_buf);
return ret;
}
static int mlx5vf_prep_stop_copy(struct mlx5_vf_migration_file *migf,
size_t state_size)
{
struct mlx5_vhca_data_buffer *buf;
size_t inc_state_size;
int ret;
/* let's be ready for stop_copy size that might grow by 10 percents */
if (check_add_overflow(state_size, state_size / 10, &inc_state_size))
inc_state_size = state_size;
buf = mlx5vf_get_data_buffer(migf, inc_state_size, DMA_FROM_DEVICE);
if (IS_ERR(buf))
return PTR_ERR(buf);
migf->buf = buf;
buf = mlx5vf_get_data_buffer(migf,
sizeof(struct mlx5_vf_migration_header), DMA_NONE);
if (IS_ERR(buf)) {
ret = PTR_ERR(buf);
goto err;
}
migf->buf_header = buf;
ret = mlx5vf_add_stop_copy_header(migf);
if (ret)
goto err_header;
return 0;
err_header:
mlx5vf_put_data_buffer(migf->buf_header);
migf->buf_header = NULL;
err:
mlx5vf_put_data_buffer(migf->buf);
migf->buf = NULL;
return ret;
}
static long mlx5vf_precopy_ioctl(struct file *filp, unsigned int cmd,
unsigned long arg)
{
struct mlx5_vf_migration_file *migf = filp->private_data;
struct mlx5vf_pci_core_device *mvdev = migf->mvdev;
struct mlx5_vhca_data_buffer *buf;
struct vfio_precopy_info info = {};
loff_t *pos = &filp->f_pos;
unsigned long minsz;
size_t inc_length = 0;
bool end_of_data = false;
int ret;
if (cmd != VFIO_MIG_GET_PRECOPY_INFO)
return -ENOTTY;
minsz = offsetofend(struct vfio_precopy_info, dirty_bytes);
if (copy_from_user(&info, (void __user *)arg, minsz))
return -EFAULT;
if (info.argsz < minsz)
return -EINVAL;
mutex_lock(&mvdev->state_mutex);
if (mvdev->mig_state != VFIO_DEVICE_STATE_PRE_COPY &&
mvdev->mig_state != VFIO_DEVICE_STATE_PRE_COPY_P2P) {
ret = -EINVAL;
goto err_state_unlock;
}
/*
* We can't issue a SAVE command when the device is suspended, so as
* part of VFIO_DEVICE_STATE_PRE_COPY_P2P no reason to query for extra
* bytes that can't be read.
*/
if (mvdev->mig_state == VFIO_DEVICE_STATE_PRE_COPY) {
/*
* Once the query returns it's guaranteed that there is no
* active SAVE command.
* As so, the other code below is safe with the proper locks.
*/
ret = mlx5vf_cmd_query_vhca_migration_state(mvdev, &inc_length,
MLX5VF_QUERY_INC);
if (ret)
goto err_state_unlock;
}
mutex_lock(&migf->lock);
if (migf->state == MLX5_MIGF_STATE_ERROR) {
ret = -ENODEV;
goto err_migf_unlock;
}
if (migf->pre_copy_initial_bytes > *pos) {
info.initial_bytes = migf->pre_copy_initial_bytes - *pos;
} else {
info.dirty_bytes = migf->max_pos - *pos;
if (!info.dirty_bytes)
end_of_data = true;
info.dirty_bytes += inc_length;
}
if (!end_of_data || !inc_length) {
mutex_unlock(&migf->lock);
goto done;
}
mutex_unlock(&migf->lock);
/*
* We finished transferring the current state and the device has a
* dirty state, save a new state to be ready for.
*/
buf = mlx5vf_get_data_buffer(migf, inc_length, DMA_FROM_DEVICE);
if (IS_ERR(buf)) {
ret = PTR_ERR(buf);
mlx5vf_mark_err(migf);
goto err_state_unlock;
}
ret = mlx5vf_cmd_save_vhca_state(mvdev, migf, buf, true, true);
if (ret) {
mlx5vf_mark_err(migf);
mlx5vf_put_data_buffer(buf);
goto err_state_unlock;
}
done:
mlx5vf_state_mutex_unlock(mvdev);
if (copy_to_user((void __user *)arg, &info, minsz))
return -EFAULT;
return 0;
err_migf_unlock:
mutex_unlock(&migf->lock);
err_state_unlock:
mlx5vf_state_mutex_unlock(mvdev);
return ret;
}
static const struct file_operations mlx5vf_save_fops = {
.owner = THIS_MODULE,
.read = mlx5vf_save_read,
.poll = mlx5vf_save_poll,
.unlocked_ioctl = mlx5vf_precopy_ioctl,
.compat_ioctl = compat_ptr_ioctl,
.release = mlx5vf_release_file,
.llseek = no_llseek,
};
static int mlx5vf_pci_save_device_inc_data(struct mlx5vf_pci_core_device *mvdev)
{
struct mlx5_vf_migration_file *migf = mvdev->saving_migf;
struct mlx5_vhca_data_buffer *buf;
size_t length;
int ret;
if (migf->state == MLX5_MIGF_STATE_ERROR)
return -ENODEV;
ret = mlx5vf_cmd_query_vhca_migration_state(mvdev, &length,
MLX5VF_QUERY_INC | MLX5VF_QUERY_FINAL);
if (ret)
goto err;
/* Checking whether we have a matching pre-allocated buffer that can fit */
if (migf->buf && migf->buf->allocated_length >= length) {
buf = migf->buf;
migf->buf = NULL;
} else {
buf = mlx5vf_get_data_buffer(migf, length, DMA_FROM_DEVICE);
if (IS_ERR(buf)) {
ret = PTR_ERR(buf);
goto err;
}
}
ret = mlx5vf_cmd_save_vhca_state(mvdev, migf, buf, true, false);
if (ret)
goto err_save;
return 0;
err_save:
mlx5vf_put_data_buffer(buf);
err:
mlx5vf_mark_err(migf);
return ret;
}
static struct mlx5_vf_migration_file *
mlx5vf_pci_save_device_data(struct mlx5vf_pci_core_device *mvdev, bool track)
{
struct mlx5_vf_migration_file *migf;
struct mlx5_vhca_data_buffer *buf;
size_t length;
int ret;
migf = kzalloc(sizeof(*migf), GFP_KERNEL_ACCOUNT);
if (!migf)
return ERR_PTR(-ENOMEM);
migf->filp = anon_inode_getfile("mlx5vf_mig", &mlx5vf_save_fops, migf,
O_RDONLY);
if (IS_ERR(migf->filp)) {
ret = PTR_ERR(migf->filp);
goto end;
}
migf->mvdev = mvdev;
ret = mlx5vf_cmd_alloc_pd(migf);
if (ret)
goto out_free;
stream_open(migf->filp->f_inode, migf->filp);
mutex_init(&migf->lock);
init_waitqueue_head(&migf->poll_wait);
init_completion(&migf->save_comp);
/*
* save_comp is being used as a binary semaphore built from
* a completion. A normal mutex cannot be used because the lock is
* passed between kernel threads and lockdep can't model this.
*/
complete(&migf->save_comp);
mlx5_cmd_init_async_ctx(mvdev->mdev, &migf->async_ctx);
INIT_WORK(&migf->async_data.work, mlx5vf_mig_file_cleanup_cb);
INIT_LIST_HEAD(&migf->buf_list);
INIT_LIST_HEAD(&migf->avail_list);
spin_lock_init(&migf->list_lock);
ret = mlx5vf_cmd_query_vhca_migration_state(mvdev, &length, 0);
if (ret)
goto out_pd;
if (track) {
ret = mlx5vf_prep_stop_copy(migf, length);
if (ret)
goto out_pd;
}
buf = mlx5vf_alloc_data_buffer(migf, length, DMA_FROM_DEVICE);
if (IS_ERR(buf)) {
ret = PTR_ERR(buf);
goto out_pd;
}
ret = mlx5vf_cmd_save_vhca_state(mvdev, migf, buf, false, track);
if (ret)
goto out_save;
return migf;
out_save:
mlx5vf_free_data_buffer(buf);
out_pd:
mlx5fv_cmd_clean_migf_resources(migf);
out_free:
fput(migf->filp);
end:
kfree(migf);
return ERR_PTR(ret);
}
static int
mlx5vf_append_page_to_mig_buf(struct mlx5_vhca_data_buffer *vhca_buf,
const char __user **buf, size_t *len,
loff_t *pos, ssize_t *done)
{
unsigned long offset;
size_t page_offset;
struct page *page;
size_t page_len;
u8 *to_buff;
int ret;
offset = *pos - vhca_buf->start_pos;
page_offset = offset % PAGE_SIZE;
page = mlx5vf_get_migration_page(vhca_buf, offset - page_offset);
if (!page)
return -EINVAL;
page_len = min_t(size_t, *len, PAGE_SIZE - page_offset);
to_buff = kmap_local_page(page);
ret = copy_from_user(to_buff + page_offset, *buf, page_len);
kunmap_local(to_buff);
if (ret)
return -EFAULT;
*pos += page_len;
*done += page_len;
*buf += page_len;
*len -= page_len;
vhca_buf->length += page_len;
return 0;
}
static int
mlx5vf_resume_read_image_no_header(struct mlx5_vhca_data_buffer *vhca_buf,
loff_t requested_length,
const char __user **buf, size_t *len,
loff_t *pos, ssize_t *done)
{
int ret;
if (requested_length > MAX_LOAD_SIZE)
return -ENOMEM;
if (vhca_buf->allocated_length < requested_length) {
ret = mlx5vf_add_migration_pages(
vhca_buf,
DIV_ROUND_UP(requested_length - vhca_buf->allocated_length,
PAGE_SIZE));
if (ret)
return ret;
}
while (*len) {
ret = mlx5vf_append_page_to_mig_buf(vhca_buf, buf, len, pos,
done);
if (ret)
return ret;
}
return 0;
}
static ssize_t
mlx5vf_resume_read_image(struct mlx5_vf_migration_file *migf,
struct mlx5_vhca_data_buffer *vhca_buf,
size_t image_size, const char __user **buf,
size_t *len, loff_t *pos, ssize_t *done,
bool *has_work)
{
size_t copy_len, to_copy;
int ret;
to_copy = min_t(size_t, *len, image_size - vhca_buf->length);
copy_len = to_copy;
while (to_copy) {
ret = mlx5vf_append_page_to_mig_buf(vhca_buf, buf, &to_copy, pos,
done);
if (ret)
return ret;
}
*len -= copy_len;
if (vhca_buf->length == image_size) {
migf->load_state = MLX5_VF_LOAD_STATE_LOAD_IMAGE;
migf->max_pos += image_size;
*has_work = true;
}
return 0;
}
static int
mlx5vf_resume_read_header_data(struct mlx5_vf_migration_file *migf,
struct mlx5_vhca_data_buffer *vhca_buf,
const char __user **buf, size_t *len,
loff_t *pos, ssize_t *done)
{
size_t copy_len, to_copy;
size_t required_data;
u8 *to_buff;
int ret;
required_data = migf->record_size - vhca_buf->length;
to_copy = min_t(size_t, *len, required_data);
copy_len = to_copy;
while (to_copy) {
ret = mlx5vf_append_page_to_mig_buf(vhca_buf, buf, &to_copy, pos,
done);
if (ret)
return ret;
}
*len -= copy_len;
if (vhca_buf->length == migf->record_size) {
switch (migf->record_tag) {
case MLX5_MIGF_HEADER_TAG_STOP_COPY_SIZE:
{
struct page *page;
page = mlx5vf_get_migration_page(vhca_buf, 0);
if (!page)
return -EINVAL;
to_buff = kmap_local_page(page);
migf->stop_copy_prep_size = min_t(u64,
le64_to_cpup((__le64 *)to_buff), MAX_LOAD_SIZE);
kunmap_local(to_buff);
break;
}
default:
/* Optional tag */
break;
}
migf->load_state = MLX5_VF_LOAD_STATE_READ_HEADER;
migf->max_pos += migf->record_size;
vhca_buf->length = 0;
}
return 0;
}
static int
mlx5vf_resume_read_header(struct mlx5_vf_migration_file *migf,
struct mlx5_vhca_data_buffer *vhca_buf,
const char __user **buf,
size_t *len, loff_t *pos,
ssize_t *done, bool *has_work)
{
struct page *page;
size_t copy_len;
u8 *to_buff;
int ret;
copy_len = min_t(size_t, *len,
sizeof(struct mlx5_vf_migration_header) - vhca_buf->length);
page = mlx5vf_get_migration_page(vhca_buf, 0);
if (!page)
return -EINVAL;
to_buff = kmap_local_page(page);
ret = copy_from_user(to_buff + vhca_buf->length, *buf, copy_len);
if (ret) {
ret = -EFAULT;
goto end;
}
*buf += copy_len;
*pos += copy_len;
*done += copy_len;
*len -= copy_len;
vhca_buf->length += copy_len;
if (vhca_buf->length == sizeof(struct mlx5_vf_migration_header)) {
u64 record_size;
u32 flags;
record_size = le64_to_cpup((__le64 *)to_buff);
if (record_size > MAX_LOAD_SIZE) {
ret = -ENOMEM;
goto end;
}
migf->record_size = record_size;
flags = le32_to_cpup((__le32 *)(to_buff +
offsetof(struct mlx5_vf_migration_header, flags)));
migf->record_tag = le32_to_cpup((__le32 *)(to_buff +
offsetof(struct mlx5_vf_migration_header, tag)));
switch (migf->record_tag) {
case MLX5_MIGF_HEADER_TAG_FW_DATA:
migf->load_state = MLX5_VF_LOAD_STATE_PREP_IMAGE;
break;
case MLX5_MIGF_HEADER_TAG_STOP_COPY_SIZE:
migf->load_state = MLX5_VF_LOAD_STATE_PREP_HEADER_DATA;
break;
default:
if (!(flags & MLX5_MIGF_HEADER_FLAGS_TAG_OPTIONAL)) {
ret = -EOPNOTSUPP;
goto end;
}
/* We may read and skip this optional record data */
migf->load_state = MLX5_VF_LOAD_STATE_PREP_HEADER_DATA;
}
migf->max_pos += vhca_buf->length;
vhca_buf->length = 0;
*has_work = true;
}
end:
kunmap_local(to_buff);
return ret;
}
static ssize_t mlx5vf_resume_write(struct file *filp, const char __user *buf,
size_t len, loff_t *pos)
{
struct mlx5_vf_migration_file *migf = filp->private_data;
struct mlx5_vhca_data_buffer *vhca_buf = migf->buf;
struct mlx5_vhca_data_buffer *vhca_buf_header = migf->buf_header;
loff_t requested_length;
bool has_work = false;
ssize_t done = 0;
int ret = 0;
if (pos)
return -ESPIPE;
pos = &filp->f_pos;
if (*pos < 0 ||
check_add_overflow((loff_t)len, *pos, &requested_length))
return -EINVAL;
mutex_lock(&migf->mvdev->state_mutex);
mutex_lock(&migf->lock);
if (migf->state == MLX5_MIGF_STATE_ERROR) {
ret = -ENODEV;
goto out_unlock;
}
while (len || has_work) {
has_work = false;
switch (migf->load_state) {
case MLX5_VF_LOAD_STATE_READ_HEADER:
ret = mlx5vf_resume_read_header(migf, vhca_buf_header,
&buf, &len, pos,
&done, &has_work);
if (ret)
goto out_unlock;
break;
case MLX5_VF_LOAD_STATE_PREP_HEADER_DATA:
if (vhca_buf_header->allocated_length < migf->record_size) {
mlx5vf_free_data_buffer(vhca_buf_header);
migf->buf_header = mlx5vf_alloc_data_buffer(migf,
migf->record_size, DMA_NONE);
if (IS_ERR(migf->buf_header)) {
ret = PTR_ERR(migf->buf_header);
migf->buf_header = NULL;
goto out_unlock;
}
vhca_buf_header = migf->buf_header;
}
vhca_buf_header->start_pos = migf->max_pos;
migf->load_state = MLX5_VF_LOAD_STATE_READ_HEADER_DATA;
break;
case MLX5_VF_LOAD_STATE_READ_HEADER_DATA:
ret = mlx5vf_resume_read_header_data(migf, vhca_buf_header,
&buf, &len, pos, &done);
if (ret)
goto out_unlock;
break;
case MLX5_VF_LOAD_STATE_PREP_IMAGE:
{
u64 size = max(migf->record_size,
migf->stop_copy_prep_size);
if (vhca_buf->allocated_length < size) {
mlx5vf_free_data_buffer(vhca_buf);
migf->buf = mlx5vf_alloc_data_buffer(migf,
size, DMA_TO_DEVICE);
if (IS_ERR(migf->buf)) {
ret = PTR_ERR(migf->buf);
migf->buf = NULL;
goto out_unlock;
}
vhca_buf = migf->buf;
}
vhca_buf->start_pos = migf->max_pos;
migf->load_state = MLX5_VF_LOAD_STATE_READ_IMAGE;
break;
}
case MLX5_VF_LOAD_STATE_READ_IMAGE_NO_HEADER:
ret = mlx5vf_resume_read_image_no_header(vhca_buf,
requested_length,
&buf, &len, pos, &done);
if (ret)
goto out_unlock;
break;
case MLX5_VF_LOAD_STATE_READ_IMAGE:
ret = mlx5vf_resume_read_image(migf, vhca_buf,
migf->record_size,
&buf, &len, pos, &done, &has_work);
if (ret)
goto out_unlock;
break;
case MLX5_VF_LOAD_STATE_LOAD_IMAGE:
ret = mlx5vf_cmd_load_vhca_state(migf->mvdev, migf, vhca_buf);
if (ret)
goto out_unlock;
migf->load_state = MLX5_VF_LOAD_STATE_READ_HEADER;
/* prep header buf for next image */
vhca_buf_header->length = 0;
/* prep data buf for next image */
vhca_buf->length = 0;
break;
default:
break;
}
}
out_unlock:
if (ret)
migf->state = MLX5_MIGF_STATE_ERROR;
mutex_unlock(&migf->lock);
mlx5vf_state_mutex_unlock(migf->mvdev);
return ret ? ret : done;
}
static const struct file_operations mlx5vf_resume_fops = {
.owner = THIS_MODULE,
.write = mlx5vf_resume_write,
.release = mlx5vf_release_file,
.llseek = no_llseek,
};
static struct mlx5_vf_migration_file *
mlx5vf_pci_resume_device_data(struct mlx5vf_pci_core_device *mvdev)
{
struct mlx5_vf_migration_file *migf;
struct mlx5_vhca_data_buffer *buf;
int ret;
migf = kzalloc(sizeof(*migf), GFP_KERNEL_ACCOUNT);
if (!migf)
return ERR_PTR(-ENOMEM);
migf->filp = anon_inode_getfile("mlx5vf_mig", &mlx5vf_resume_fops, migf,
O_WRONLY);
if (IS_ERR(migf->filp)) {
ret = PTR_ERR(migf->filp);
goto end;
}
migf->mvdev = mvdev;
ret = mlx5vf_cmd_alloc_pd(migf);
if (ret)
goto out_free;
buf = mlx5vf_alloc_data_buffer(migf, 0, DMA_TO_DEVICE);
if (IS_ERR(buf)) {
ret = PTR_ERR(buf);
goto out_pd;
}
migf->buf = buf;
if (MLX5VF_PRE_COPY_SUPP(mvdev)) {
buf = mlx5vf_alloc_data_buffer(migf,
sizeof(struct mlx5_vf_migration_header), DMA_NONE);
if (IS_ERR(buf)) {
ret = PTR_ERR(buf);
goto out_buf;
}
migf->buf_header = buf;
migf->load_state = MLX5_VF_LOAD_STATE_READ_HEADER;
} else {
/* Initial state will be to read the image */
migf->load_state = MLX5_VF_LOAD_STATE_READ_IMAGE_NO_HEADER;
}
stream_open(migf->filp->f_inode, migf->filp);
mutex_init(&migf->lock);
INIT_LIST_HEAD(&migf->buf_list);
INIT_LIST_HEAD(&migf->avail_list);
spin_lock_init(&migf->list_lock);
return migf;
out_buf:
mlx5vf_free_data_buffer(migf->buf);
out_pd:
mlx5vf_cmd_dealloc_pd(migf);
out_free:
fput(migf->filp);
end:
kfree(migf);
return ERR_PTR(ret);
}
void mlx5vf_disable_fds(struct mlx5vf_pci_core_device *mvdev)
{
if (mvdev->resuming_migf) {
mlx5vf_disable_fd(mvdev->resuming_migf);
mlx5fv_cmd_clean_migf_resources(mvdev->resuming_migf);
fput(mvdev->resuming_migf->filp);
mvdev->resuming_migf = NULL;
}
if (mvdev->saving_migf) {
mlx5_cmd_cleanup_async_ctx(&mvdev->saving_migf->async_ctx);
cancel_work_sync(&mvdev->saving_migf->async_data.work);
mlx5vf_disable_fd(mvdev->saving_migf);
mlx5fv_cmd_clean_migf_resources(mvdev->saving_migf);
fput(mvdev->saving_migf->filp);
mvdev->saving_migf = NULL;
}
}
static struct file *
mlx5vf_pci_step_device_state_locked(struct mlx5vf_pci_core_device *mvdev,
u32 new)
{
u32 cur = mvdev->mig_state;
int ret;
if (cur == VFIO_DEVICE_STATE_RUNNING_P2P && new == VFIO_DEVICE_STATE_STOP) {
ret = mlx5vf_cmd_suspend_vhca(mvdev,
MLX5_SUSPEND_VHCA_IN_OP_MOD_SUSPEND_RESPONDER);
if (ret)
return ERR_PTR(ret);
return NULL;
}
if (cur == VFIO_DEVICE_STATE_STOP && new == VFIO_DEVICE_STATE_RUNNING_P2P) {
ret = mlx5vf_cmd_resume_vhca(mvdev,
MLX5_RESUME_VHCA_IN_OP_MOD_RESUME_RESPONDER);
if (ret)
return ERR_PTR(ret);
return NULL;
}
if ((cur == VFIO_DEVICE_STATE_RUNNING && new == VFIO_DEVICE_STATE_RUNNING_P2P) ||
(cur == VFIO_DEVICE_STATE_PRE_COPY && new == VFIO_DEVICE_STATE_PRE_COPY_P2P)) {
ret = mlx5vf_cmd_suspend_vhca(mvdev,
MLX5_SUSPEND_VHCA_IN_OP_MOD_SUSPEND_INITIATOR);
if (ret)
return ERR_PTR(ret);
return NULL;
}
if ((cur == VFIO_DEVICE_STATE_RUNNING_P2P && new == VFIO_DEVICE_STATE_RUNNING) ||
(cur == VFIO_DEVICE_STATE_PRE_COPY_P2P && new == VFIO_DEVICE_STATE_PRE_COPY)) {
ret = mlx5vf_cmd_resume_vhca(mvdev,
MLX5_RESUME_VHCA_IN_OP_MOD_RESUME_INITIATOR);
if (ret)
return ERR_PTR(ret);
return NULL;
}
if (cur == VFIO_DEVICE_STATE_STOP && new == VFIO_DEVICE_STATE_STOP_COPY) {
struct mlx5_vf_migration_file *migf;
migf = mlx5vf_pci_save_device_data(mvdev, false);
if (IS_ERR(migf))
return ERR_CAST(migf);
get_file(migf->filp);
mvdev->saving_migf = migf;
return migf->filp;
}
if ((cur == VFIO_DEVICE_STATE_STOP_COPY && new == VFIO_DEVICE_STATE_STOP) ||
(cur == VFIO_DEVICE_STATE_PRE_COPY && new == VFIO_DEVICE_STATE_RUNNING) ||
(cur == VFIO_DEVICE_STATE_PRE_COPY_P2P &&
new == VFIO_DEVICE_STATE_RUNNING_P2P)) {
mlx5vf_disable_fds(mvdev);
return NULL;
}
if (cur == VFIO_DEVICE_STATE_STOP && new == VFIO_DEVICE_STATE_RESUMING) {
struct mlx5_vf_migration_file *migf;
migf = mlx5vf_pci_resume_device_data(mvdev);
if (IS_ERR(migf))
return ERR_CAST(migf);
get_file(migf->filp);
mvdev->resuming_migf = migf;
return migf->filp;
}
if (cur == VFIO_DEVICE_STATE_RESUMING && new == VFIO_DEVICE_STATE_STOP) {
if (!MLX5VF_PRE_COPY_SUPP(mvdev)) {
ret = mlx5vf_cmd_load_vhca_state(mvdev,
mvdev->resuming_migf,
mvdev->resuming_migf->buf);
if (ret)
return ERR_PTR(ret);
}
mlx5vf_disable_fds(mvdev);
return NULL;
}
if ((cur == VFIO_DEVICE_STATE_RUNNING && new == VFIO_DEVICE_STATE_PRE_COPY) ||
(cur == VFIO_DEVICE_STATE_RUNNING_P2P &&
new == VFIO_DEVICE_STATE_PRE_COPY_P2P)) {
struct mlx5_vf_migration_file *migf;
migf = mlx5vf_pci_save_device_data(mvdev, true);
if (IS_ERR(migf))
return ERR_CAST(migf);
get_file(migf->filp);
mvdev->saving_migf = migf;
return migf->filp;
}
if (cur == VFIO_DEVICE_STATE_PRE_COPY_P2P && new == VFIO_DEVICE_STATE_STOP_COPY) {
ret = mlx5vf_cmd_suspend_vhca(mvdev,
MLX5_SUSPEND_VHCA_IN_OP_MOD_SUSPEND_RESPONDER);
if (ret)
return ERR_PTR(ret);
ret = mlx5vf_pci_save_device_inc_data(mvdev);
return ret ? ERR_PTR(ret) : NULL;
}
/*
* vfio_mig_get_next_state() does not use arcs other than the above
*/
WARN_ON(true);
return ERR_PTR(-EINVAL);
}
/*
* This function is called in all state_mutex unlock cases to
* handle a 'deferred_reset' if exists.
*/
void mlx5vf_state_mutex_unlock(struct mlx5vf_pci_core_device *mvdev)
{
again:
spin_lock(&mvdev->reset_lock);
if (mvdev->deferred_reset) {
mvdev->deferred_reset = false;
spin_unlock(&mvdev->reset_lock);
mvdev->mig_state = VFIO_DEVICE_STATE_RUNNING;
mlx5vf_disable_fds(mvdev);
goto again;
}
mutex_unlock(&mvdev->state_mutex);
spin_unlock(&mvdev->reset_lock);
}
static struct file *
mlx5vf_pci_set_device_state(struct vfio_device *vdev,
enum vfio_device_mig_state new_state)
{
struct mlx5vf_pci_core_device *mvdev = container_of(
vdev, struct mlx5vf_pci_core_device, core_device.vdev);
enum vfio_device_mig_state next_state;
struct file *res = NULL;
int ret;
mutex_lock(&mvdev->state_mutex);
while (new_state != mvdev->mig_state) {
ret = vfio_mig_get_next_state(vdev, mvdev->mig_state,
new_state, &next_state);
if (ret) {
res = ERR_PTR(ret);
break;
}
res = mlx5vf_pci_step_device_state_locked(mvdev, next_state);
if (IS_ERR(res))
break;
mvdev->mig_state = next_state;
if (WARN_ON(res && new_state != mvdev->mig_state)) {
fput(res);
res = ERR_PTR(-EINVAL);
break;
}
}
mlx5vf_state_mutex_unlock(mvdev);
return res;
}
static int mlx5vf_pci_get_data_size(struct vfio_device *vdev,
unsigned long *stop_copy_length)
{
struct mlx5vf_pci_core_device *mvdev = container_of(
vdev, struct mlx5vf_pci_core_device, core_device.vdev);
size_t state_size;
int ret;
mutex_lock(&mvdev->state_mutex);
ret = mlx5vf_cmd_query_vhca_migration_state(mvdev,
&state_size, 0);
if (!ret)
*stop_copy_length = state_size;
mlx5vf_state_mutex_unlock(mvdev);
return ret;
}
static int mlx5vf_pci_get_device_state(struct vfio_device *vdev,
enum vfio_device_mig_state *curr_state)
{
struct mlx5vf_pci_core_device *mvdev = container_of(
vdev, struct mlx5vf_pci_core_device, core_device.vdev);
mutex_lock(&mvdev->state_mutex);
*curr_state = mvdev->mig_state;
mlx5vf_state_mutex_unlock(mvdev);
return 0;
}
static void mlx5vf_pci_aer_reset_done(struct pci_dev *pdev)
{
struct mlx5vf_pci_core_device *mvdev = mlx5vf_drvdata(pdev);
if (!mvdev->migrate_cap)
return;
/*
* As the higher VFIO layers are holding locks across reset and using
* those same locks with the mm_lock we need to prevent ABBA deadlock
* with the state_mutex and mm_lock.
* In case the state_mutex was taken already we defer the cleanup work
* to the unlock flow of the other running context.
*/
spin_lock(&mvdev->reset_lock);
mvdev->deferred_reset = true;
if (!mutex_trylock(&mvdev->state_mutex)) {
spin_unlock(&mvdev->reset_lock);
return;
}
spin_unlock(&mvdev->reset_lock);
mlx5vf_state_mutex_unlock(mvdev);
}
static int mlx5vf_pci_open_device(struct vfio_device *core_vdev)
{
struct mlx5vf_pci_core_device *mvdev = container_of(
core_vdev, struct mlx5vf_pci_core_device, core_device.vdev);
struct vfio_pci_core_device *vdev = &mvdev->core_device;
int ret;
ret = vfio_pci_core_enable(vdev);
if (ret)
return ret;
if (mvdev->migrate_cap)
mvdev->mig_state = VFIO_DEVICE_STATE_RUNNING;
vfio_pci_core_finish_enable(vdev);
return 0;
}
static void mlx5vf_pci_close_device(struct vfio_device *core_vdev)
{
struct mlx5vf_pci_core_device *mvdev = container_of(
core_vdev, struct mlx5vf_pci_core_device, core_device.vdev);
mlx5vf_cmd_close_migratable(mvdev);
vfio_pci_core_close_device(core_vdev);
}
static const struct vfio_migration_ops mlx5vf_pci_mig_ops = {
.migration_set_state = mlx5vf_pci_set_device_state,
.migration_get_state = mlx5vf_pci_get_device_state,
.migration_get_data_size = mlx5vf_pci_get_data_size,
};
static const struct vfio_log_ops mlx5vf_pci_log_ops = {
.log_start = mlx5vf_start_page_tracker,
.log_stop = mlx5vf_stop_page_tracker,
.log_read_and_clear = mlx5vf_tracker_read_and_clear,
};
static int mlx5vf_pci_init_dev(struct vfio_device *core_vdev)
{
struct mlx5vf_pci_core_device *mvdev = container_of(core_vdev,
struct mlx5vf_pci_core_device, core_device.vdev);
int ret;
ret = vfio_pci_core_init_dev(core_vdev);
if (ret)
return ret;
mlx5vf_cmd_set_migratable(mvdev, &mlx5vf_pci_mig_ops,
&mlx5vf_pci_log_ops);
return 0;
}
static void mlx5vf_pci_release_dev(struct vfio_device *core_vdev)
{
struct mlx5vf_pci_core_device *mvdev = container_of(core_vdev,
struct mlx5vf_pci_core_device, core_device.vdev);
mlx5vf_cmd_remove_migratable(mvdev);
vfio_pci_core_release_dev(core_vdev);
}
static const struct vfio_device_ops mlx5vf_pci_ops = {
.name = "mlx5-vfio-pci",
.init = mlx5vf_pci_init_dev,
.release = mlx5vf_pci_release_dev,
.open_device = mlx5vf_pci_open_device,
.close_device = mlx5vf_pci_close_device,
.ioctl = vfio_pci_core_ioctl,
.device_feature = vfio_pci_core_ioctl_feature,
.read = vfio_pci_core_read,
.write = vfio_pci_core_write,
.mmap = vfio_pci_core_mmap,
.request = vfio_pci_core_request,
.match = vfio_pci_core_match,
.bind_iommufd = vfio_iommufd_physical_bind,
.unbind_iommufd = vfio_iommufd_physical_unbind,
.attach_ioas = vfio_iommufd_physical_attach_ioas,
};
static int mlx5vf_pci_probe(struct pci_dev *pdev,
const struct pci_device_id *id)
{
struct mlx5vf_pci_core_device *mvdev;
int ret;
mvdev = vfio_alloc_device(mlx5vf_pci_core_device, core_device.vdev,
&pdev->dev, &mlx5vf_pci_ops);
if (IS_ERR(mvdev))
return PTR_ERR(mvdev);
dev_set_drvdata(&pdev->dev, &mvdev->core_device);
ret = vfio_pci_core_register_device(&mvdev->core_device);
if (ret)
goto out_put_vdev;
return 0;
out_put_vdev:
vfio_put_device(&mvdev->core_device.vdev);
return ret;
}
static void mlx5vf_pci_remove(struct pci_dev *pdev)
{
struct mlx5vf_pci_core_device *mvdev = mlx5vf_drvdata(pdev);
vfio_pci_core_unregister_device(&mvdev->core_device);
vfio_put_device(&mvdev->core_device.vdev);
}
static const struct pci_device_id mlx5vf_pci_table[] = {
{ PCI_DRIVER_OVERRIDE_DEVICE_VFIO(PCI_VENDOR_ID_MELLANOX, 0x101e) }, /* ConnectX Family mlx5Gen Virtual Function */
{}
};
MODULE_DEVICE_TABLE(pci, mlx5vf_pci_table);
static const struct pci_error_handlers mlx5vf_err_handlers = {
.reset_done = mlx5vf_pci_aer_reset_done,
.error_detected = vfio_pci_core_aer_err_detected,
};
static struct pci_driver mlx5vf_pci_driver = {
.name = KBUILD_MODNAME,
.id_table = mlx5vf_pci_table,
.probe = mlx5vf_pci_probe,
.remove = mlx5vf_pci_remove,
.err_handler = &mlx5vf_err_handlers,
.driver_managed_dma = true,
};
module_pci_driver(mlx5vf_pci_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Max Gurtovoy <mgurtovoy@nvidia.com>");
MODULE_AUTHOR("Yishai Hadas <yishaih@nvidia.com>");
MODULE_DESCRIPTION(
"MLX5 VFIO PCI - User Level meta-driver for MLX5 device family");