* Kirti Wankhede (kwankhede@xxxxxxxxxx) wrote:
> This patch makes mtty device migration capable. Purpose od this code is
> to test migration interface. Only stop-and-copy phase is implemented.
> Postcopy migration is not supported.
>
> Actual data for mtty device migration is very less. Appended dummy data to
> migration data stream, default 100 Mbytes. Added sysfs file
> 'dummy_data_size_MB' to get dummy data size from user which can be used
> to check performance of based of data size. During resuming dummy data is
> read and discarded.
>
> Signed-off-by: Kirti Wankhede <kwankhede@xxxxxxxxxx>
> ---
> samples/vfio-mdev/mtty.c | 602 ++++++++++++++++++++++++++++++++++++++++++++---
> 1 file changed, 574 insertions(+), 28 deletions(-)
>
> diff --git a/samples/vfio-mdev/mtty.c b/samples/vfio-mdev/mtty.c
> index bf666cce5bb7..f9194234fc6a 100644
> --- a/samples/vfio-mdev/mtty.c
> +++ b/samples/vfio-mdev/mtty.c
> @@ -44,9 +44,23 @@
>
> #define MTTY_STRING_LEN 16
>
> -#define MTTY_CONFIG_SPACE_SIZE 0xff
> -#define MTTY_IO_BAR_SIZE 0x8
> -#define MTTY_MMIO_BAR_SIZE 0x100000
> +#define MTTY_CONFIG_SPACE_SIZE 0xff
> +#define MTTY_IO_BAR_SIZE 0x8
> +#define MTTY_MMIO_BAR_SIZE 0x100000
> +#define MTTY_MIGRATION_REGION_SIZE 0x1000000 // 16M
> +
> +#define MTTY_MIGRATION_REGION_INDEX VFIO_PCI_NUM_REGIONS
> +#define MTTY_REGIONS_MAX (MTTY_MIGRATION_REGION_INDEX + 1)
> +
> +/* Data section start from page aligned offset */
> +#define MTTY_MIGRATION_REGION_DATA_OFFSET (0x1000)
> +
> +/* First page is used for struct vfio_device_migration_info */
> +#define MTTY_MIGRATION_REGION_SIZE_MMAP \
> + (MTTY_MIGRATION_REGION_SIZE - MTTY_MIGRATION_REGION_DATA_OFFSET)
> +
> +#define MIGRATION_INFO_OFFSET(MEMBER) \
> + offsetof(struct vfio_device_migration_info, MEMBER)
>
> #define STORE_LE16(addr, val) (*(u16 *)addr = val)
> #define STORE_LE32(addr, val) (*(u32 *)addr = val)
> @@ -129,6 +143,28 @@ struct serial_port {
> u8 intr_trigger_level; /* interrupt trigger level */
> };
>
> +/* Migration packet */
> +#define PACKET_ID (u16)(0xfeedbaba)
> +
> +#define PACKET_FLAGS_ACTUAL_DATA (1 << 0)
> +#define PACKET_FLAGS_DUMMY_DATA (1 << 1)
> +
> +#define PACKET_DATA_SIZE_MAX (8 * 1024 * 1024)
> +
> +struct packet {
> + u16 id;
> + u16 flags;
> + u32 data_size;
> + u8 data[];
> +};
> +
> +enum {
> + PACKET_STATE_NONE = 0,
> + PACKET_STATE_PREPARED,
> + PACKET_STATE_COPIED,
> + PACKET_STATE_LAST,
> +};
> +
> /* State of each mdev device */
> struct mdev_state {
> int irq_fd;
> @@ -138,22 +174,37 @@ struct mdev_state {
> u8 *vconfig;
> struct mutex ops_lock;
> struct mdev_device *mdev;
> - struct mdev_region_info region_info[VFIO_PCI_NUM_REGIONS];
> - u32 bar_mask[VFIO_PCI_NUM_REGIONS];
> + struct mdev_region_info region_info[MTTY_REGIONS_MAX];
> + u32 bar_mask[MTTY_REGIONS_MAX];
> struct list_head next;
> struct serial_port s[2];
> struct mutex rxtx_lock;
> struct vfio_device_info dev_info;
> - int nr_ports;
> + u32 nr_ports;
>
> /* List of pinned gpfns, gpfn as index and content is translated hpfn */
> unsigned long *gpfn_to_hpfn;
> struct notifier_block nb;
> +
> + u32 device_state;
> + u64 saved_size;
> + void *mig_region_base;
> + bool is_actual_data_sent;
> + struct packet *pkt;
> + u32 packet_state;
> + u64 dummy_data_size;
> };
>
> static struct mutex mdev_list_lock;
> static struct list_head mdev_devices_list;
>
> +/*
> + * Default dummy data size set to 100 MB. To change value of dummy data size at
> + * runtime but before migration write size in MB to sysfs file
> + * dummy_data_size_MB
> + */
> +static unsigned long user_dummy_data_size = (100 * 1024 * 1024);
> +
> static const struct file_operations vd_fops = {
> .owner = THIS_MODULE,
> };
> @@ -639,6 +690,288 @@ static void mdev_read_base(struct mdev_state *mdev_state)
> }
> }
>
> +static int save_setup(struct mdev_state *mdev_state)
> +{
> + mdev_state->is_actual_data_sent = false;
> +
> + memset(mdev_state->pkt, 0, sizeof(struct packet) +
> + PACKET_DATA_SIZE_MAX);
> +
> + return 0;
> +}
> +
> +static int set_device_state(struct mdev_state *mdev_state, u32 device_state)
> +{
> + int ret = 0;
> +
> + if (mdev_state->device_state == device_state)
> + return 0;
> +
> + if (device_state & VFIO_DEVICE_STATE_RUNNING) {
> +#if defined(DEBUG)
> + if (device_state & VFIO_DEVICE_STATE_SAVING) {
> + pr_info("%s: %s Pre-copy\n", __func__,
> + dev_name(mdev_dev(mdev_state->mdev)));
> + } else
> + pr_info("%s: %s Running\n", __func__,
> + dev_name(mdev_dev(mdev_state->mdev)));
> +#endif
> + } else {
> + if (device_state & VFIO_DEVICE_STATE_SAVING) {
> +#if defined(DEBUG)
> + pr_info("%s: %s Stop-n-copy\n", __func__,
> + dev_name(mdev_dev(mdev_state->mdev)));
> +#endif
> + ret = save_setup(mdev_state);
> +
> + } else if (device_state & VFIO_DEVICE_STATE_RESUMING) {
> +#if defined(DEBUG)
> + pr_info("%s: %s Resuming\n", __func__,
> + dev_name(mdev_dev(mdev_state->mdev)));
> + } else {
> + pr_info("%s: %s Stopped\n", __func__,
> + dev_name(mdev_dev(mdev_state->mdev)));
> +#endif
> + }
> + }
> +
> + mdev_state->device_state = device_state;
> +
> + return ret;
> +}
> +
> +static u32 get_device_state(struct mdev_state *mdev_state)
> +{
> + return mdev_state->device_state;
> +}
> +
> +static void write_to_packet(struct packet *pkt, u8 *data, size_t size)
> +{
> + if ((pkt->data_size + size) > PACKET_DATA_SIZE_MAX) {
> + pr_err("%s: packet data overflow\n", __func__);
> + return;
> + }
> + memcpy((void *)&pkt->data[pkt->data_size], (void *)data, size);
> + pkt->data_size += size;
> +}
> +
> +static void read_from_packet(struct packet *pkt, u8 *data,
> + int index, size_t size)
> +{
> + if ((index + size) > PACKET_DATA_SIZE_MAX) {
> + pr_err("%s: packet data overflow\n", __func__);
> + return;
> + }
> +
> + memcpy((void *)data, (void *)&pkt->data[index], size);
> +}
> +
> +static int save_device_data(struct mdev_state *mdev_state, u64 *pending)
> +{
> + /* Save device data only during stop-and-copy phase */
> + if (mdev_state->device_state != VFIO_DEVICE_STATE_SAVING) {
> + *pending = 0;
> + return 0;
> + }
> +
> + if (mdev_state->packet_state == PACKET_STATE_PREPARED) {
> + *pending = sizeof(struct packet) + mdev_state->pkt->data_size;
> + return 0;
> + }
> +
> + if (!mdev_state->is_actual_data_sent) {
> +
> + /* create actual data packet */
> + write_to_packet(mdev_state->pkt, (u8 *)&mdev_state->nr_ports,
> + sizeof(mdev_state->nr_ports));
> + write_to_packet(mdev_state->pkt, (u8 *)&mdev_state->s,
> + sizeof(struct serial_port) * 2);
> +
> + write_to_packet(mdev_state->pkt, mdev_state->vconfig,
> + MTTY_CONFIG_SPACE_SIZE);
> +
> + write_to_packet(mdev_state->pkt, (u8 *)mdev_state->gpfn_to_hpfn,
> + sizeof(unsigned long) * MAX_GPFN_COUNT);
> +
> + mdev_state->pkt->id = PACKET_ID;
> + mdev_state->pkt->flags = PACKET_FLAGS_ACTUAL_DATA;
> +
> + mdev_state->is_actual_data_sent = true;
> + } else {
> + /* create dummy data packet */
> + if (mdev_state->dummy_data_size > user_dummy_data_size) {
> + *pending = 0;
> + mdev_state->packet_state = PACKET_STATE_NONE;
> + return 0;
> + }
> +
> + memset(mdev_state->pkt->data, 0xa5, PACKET_DATA_SIZE_MAX);
> +
> + mdev_state->pkt->id = PACKET_ID;
> + mdev_state->pkt->flags = PACKET_FLAGS_DUMMY_DATA;
> + mdev_state->pkt->data_size = PACKET_DATA_SIZE_MAX;
> + mdev_state->dummy_data_size += PACKET_DATA_SIZE_MAX;
> + }
> +
> + *pending = sizeof(struct packet) + mdev_state->pkt->data_size;
> + mdev_state->packet_state = PACKET_STATE_PREPARED;
> + mdev_state->saved_size = 0;
> +
> + return 0;
> +}
> +
> +static int copy_device_data(struct mdev_state *mdev_state)
> +{
> + u64 size;
> +
> + if (!mdev_state->pkt || !mdev_state->mig_region_base)
> + return -EINVAL;
> +
> + if (mdev_state->packet_state == PACKET_STATE_COPIED)
> + return 0;
> +
> + if (!mdev_state->pkt->data_size)
> + return 0;
> +
> + size = sizeof(struct packet) + mdev_state->pkt->data_size;
> +
> + memcpy(mdev_state->mig_region_base, mdev_state->pkt, size);
> +
> + mdev_state->saved_size = size;
> + mdev_state->packet_state = PACKET_STATE_COPIED;
> + memset(mdev_state->pkt, 0, sizeof(struct packet));
> + return 0;
> +}
> +
> +static int resume_device_data(struct mdev_state *mdev_state, u64 data_size)
> +{
> + unsigned long i;
> +
> + if (mdev_state->device_state != VFIO_DEVICE_STATE_RESUMING)
> + return -EINVAL;
> +
> + if (!mdev_state->pkt || !mdev_state->mig_region_base)
> + return -EINVAL;
> +
> + memcpy(mdev_state->pkt, mdev_state->mig_region_base, data_size);
> +
> + if (mdev_state->pkt->flags & PACKET_FLAGS_ACTUAL_DATA) {
> + int index = 0;
> + /* restore device data */
> + read_from_packet(mdev_state->pkt, (u8 *)&mdev_state->nr_ports,
> + index, sizeof(mdev_state->nr_ports));
> + index += sizeof(mdev_state->nr_ports);
> +
> + read_from_packet(mdev_state->pkt, (u8 *)&mdev_state->s,
> + index, sizeof(struct serial_port) * 2);
> + index += sizeof(struct serial_port) * 2;
Do you need to validate what you've read at this point - for example,
the max_fifo_size, or the head/tail/count values in rxtx?
e.g. if count was 0, max_fifio_size was 255, and head was 255 would
writing to the UART_TX cause an overrun?
> +
> + read_from_packet(mdev_state->pkt, mdev_state->vconfig,
> + index, MTTY_CONFIG_SPACE_SIZE);
Similarly, PCI dev ID, capabilities etc ?
Dave
> + index += MTTY_CONFIG_SPACE_SIZE;
> +
> + read_from_packet(mdev_state->pkt,
> + (u8 *)mdev_state->gpfn_to_hpfn,
> + index, sizeof(unsigned long) * MAX_GPFN_COUNT);
> + index += sizeof(unsigned long) * MAX_GPFN_COUNT;
> +
> + for (i = 0; i < MAX_GPFN_COUNT; i++) {
> + if (mdev_state->gpfn_to_hpfn[i] != PFN_NULL) {
> + int ret;
> + unsigned long hpfn;
> +
> + ret = vfio_pin_pages(mdev_dev(mdev_state->mdev),
> + &i, 1, IOMMU_READ | IOMMU_WRITE, &hpfn);
> + if (ret <= 0) {
> + pr_err("%s: 0x%lx unpin error %d\n",
> + __func__, i, ret);
> + continue;
> + }
> + mdev_state->gpfn_to_hpfn[i] = hpfn;
> + }
> + }
> + } else {
> +#if defined(DEBUG)
> + pr_info("%s: %s discard data 0x%llx\n",
> + __func__, dev_name(mdev_dev(mdev_state->mdev)),
> + data_size);
> +#endif
> + }
> +
> + return 0;
> +}
> +
> +static int handle_mig_read(unsigned int index, struct mdev_state *mdev_state,
> + loff_t offset, u8 *buf, u32 count)
> +{
> + int ret = 0;
> + u64 pending = 0;
> +
> + switch (offset) {
> + case MIGRATION_INFO_OFFSET(device_state): // 0x00
> + *(u32 *)buf = get_device_state(mdev_state);
> + break;
> +
> + case MIGRATION_INFO_OFFSET(pending_bytes): // 0x08
> + ret = save_device_data(mdev_state, &pending);
> + if (ret)
> + break;
> + *(u64 *)buf = pending;
> + break;
> +
> + case MIGRATION_INFO_OFFSET(data_offset): // 0x10
> + if (mdev_state->device_state & VFIO_DEVICE_STATE_SAVING) {
> + ret = copy_device_data(mdev_state);
> + if (ret)
> + break;
> + }
> + *(u64 *)buf = MTTY_MIGRATION_REGION_DATA_OFFSET;
> + break;
> +
> + case MIGRATION_INFO_OFFSET(data_size): // 0x18
> + *(u64 *)buf = mdev_state->saved_size;
> + break;
> +
> + default:
> + ret = -EINVAL;
> + }
> +
> +#if defined(DEBUG)
> + pr_info("%s: %s MIG RD @0x%llx bytes: %d data: 0x%x\n",
> + __func__, dev_name(mdev_dev(mdev_state->mdev)),
> + offset, count, *(u32 *)buf);
> +#endif
> + return ret;
> +}
> +
> +static int handle_mig_write(unsigned int index, struct mdev_state *mdev_state,
> + loff_t offset, u8 *buf, u32 count)
> +{
> + int ret = 0;
> +
> +#if defined(DEBUG)
> + pr_info("%s: %s MIG WR @0x%llx bytes: %d data: 0x%x\n",
> + __func__, dev_name(mdev_dev(mdev_state->mdev)),
> + offset, count, *(u32 *)buf);
> +#endif
> + switch (offset) {
> + case MIGRATION_INFO_OFFSET(device_state): // 0x00
> + ret = set_device_state(mdev_state, *(u32 *)buf);
> + break;
> +
> + case MIGRATION_INFO_OFFSET(data_size): // 0x18
> + ret = resume_device_data(mdev_state, *(u64 *)buf);
> + break;
> +
> + case MIGRATION_INFO_OFFSET(pending_bytes): // 0x08
> + case MIGRATION_INFO_OFFSET(data_offset): // 0x10
> + default:
> + ret = -EINVAL;
> + }
> +
> + return ret;
> +}
> +
> static ssize_t mdev_access(struct mdev_device *mdev, u8 *buf, size_t count,
> loff_t pos, bool is_write)
> {
> @@ -702,6 +1035,18 @@ static ssize_t mdev_access(struct mdev_device *mdev, u8 *buf, size_t count,
> }
> break;
>
> + case MTTY_MIGRATION_REGION_INDEX:
> + if (is_write) {
> + ret = handle_mig_write(index, mdev_state, offset, buf,
> + count);
> + } else {
> + ret = handle_mig_read(index, mdev_state, offset, buf,
> + count);
> + }
> + if (ret)
> + goto accessfailed;
> + break;
> +
> default:
> ret = -1;
> goto accessfailed;
> @@ -709,7 +1054,6 @@ static ssize_t mdev_access(struct mdev_device *mdev, u8 *buf, size_t count,
>
> ret = count;
>
> -
> accessfailed:
> mutex_unlock(&mdev_state->ops_lock);
>
> @@ -819,13 +1163,29 @@ static int mtty_reset(struct mdev_device *mdev)
> static ssize_t mtty_read(struct mdev_device *mdev, char __user *buf,
> size_t count, loff_t *ppos)
> {
> - unsigned int done = 0;
> + unsigned int done = 0, index;
> int ret;
>
> + index = MTTY_VFIO_PCI_OFFSET_TO_INDEX(*ppos);
> +
> while (count) {
> size_t filled;
>
> - if (count >= 4 && !(*ppos % 4)) {
> + if ((index == MTTY_MIGRATION_REGION_INDEX) &&
> + (count >= 8 && !(*ppos % 8))) {
> + u64 val;
> +
> + ret = mdev_access(mdev, (u8 *)&val, sizeof(val),
> + *ppos, false);
> + if (ret <= 0)
> + goto read_err;
> +
> + if (copy_to_user(buf, &val, sizeof(val)))
> + goto read_err;
> +
> + filled = 8;
> +
> + } else if (count >= 4 && !(*ppos % 4)) {
> u32 val;
>
> ret = mdev_access(mdev, (u8 *)&val, sizeof(val),
> @@ -878,13 +1238,27 @@ static ssize_t mtty_read(struct mdev_device *mdev, char __user *buf,
> static ssize_t mtty_write(struct mdev_device *mdev, const char __user *buf,
> size_t count, loff_t *ppos)
> {
> - unsigned int done = 0;
> + unsigned int done = 0, index;
> int ret;
>
> + index = MTTY_VFIO_PCI_OFFSET_TO_INDEX(*ppos);
> while (count) {
> size_t filled;
>
> - if (count >= 4 && !(*ppos % 4)) {
> + if ((index == MTTY_MIGRATION_REGION_INDEX) &&
> + (count >= 8 && !(*ppos % 8))) {
> + u64 val;
> +
> + if (copy_from_user(&val, buf, sizeof(val)))
> + goto write_err;
> +
> + ret = mdev_access(mdev, (u8 *)&val, sizeof(val),
> + *ppos, true);
> + if (ret <= 0)
> + goto write_err;
> +
> + filled = 8;
> + } else if (count >= 4 && !(*ppos % 4)) {
> u32 val;
>
> if (copy_from_user(&val, buf, sizeof(val)))
> @@ -1061,12 +1435,13 @@ static int mtty_trigger_interrupt(struct mdev_state *mdev_state)
> }
>
> static int mtty_get_region_info(struct mdev_device *mdev,
> - struct vfio_region_info *region_info,
> - u16 *cap_type_id, void **cap_type)
> + struct vfio_region_info *region_info,
> + struct vfio_info_cap *caps)
> {
> unsigned int size = 0;
> struct mdev_state *mdev_state;
> - u32 bar_index;
> + u32 index;
> + int ret = 0;
>
> if (!mdev)
> return -EINVAL;
> @@ -1075,13 +1450,13 @@ static int mtty_get_region_info(struct mdev_device *mdev,
> if (!mdev_state)
> return -EINVAL;
>
> - bar_index = region_info->index;
> - if (bar_index >= VFIO_PCI_NUM_REGIONS)
> + index = region_info->index;
> + if (index >= MTTY_REGIONS_MAX)
> return -EINVAL;
>
> mutex_lock(&mdev_state->ops_lock);
>
> - switch (bar_index) {
> + switch (index) {
> case VFIO_PCI_CONFIG_REGION_INDEX:
> size = MTTY_CONFIG_SPACE_SIZE;
> break;
> @@ -1092,21 +1467,63 @@ static int mtty_get_region_info(struct mdev_device *mdev,
> if (mdev_state->nr_ports == 2)
> size = MTTY_IO_BAR_SIZE;
> break;
> + case MTTY_MIGRATION_REGION_INDEX:
> + size = MTTY_MIGRATION_REGION_SIZE;
> + break;
> default:
> size = 0;
> break;
> }
>
> - mdev_state->region_info[bar_index].size = size;
> - mdev_state->region_info[bar_index].vfio_offset =
> - MTTY_VFIO_PCI_INDEX_TO_OFFSET(bar_index);
> + mdev_state->region_info[index].size = size;
> + mdev_state->region_info[index].vfio_offset =
> + MTTY_VFIO_PCI_INDEX_TO_OFFSET(index);
>
> region_info->size = size;
> - region_info->offset = MTTY_VFIO_PCI_INDEX_TO_OFFSET(bar_index);
> + region_info->offset = MTTY_VFIO_PCI_INDEX_TO_OFFSET(index);
> region_info->flags = VFIO_REGION_INFO_FLAG_READ |
> - VFIO_REGION_INFO_FLAG_WRITE;
> + VFIO_REGION_INFO_FLAG_WRITE;
> +
> + if (index == MTTY_MIGRATION_REGION_INDEX) {
> + struct vfio_region_info_cap_sparse {
> + struct vfio_region_info_cap_sparse_mmap sparse;
> + struct vfio_region_sparse_mmap_area area;
> + };
> +
> + struct vfio_region_info_cap_sparse mig_region;
> +
> + struct vfio_region_info_cap_type cap_type = {
> + .header.id = VFIO_REGION_INFO_CAP_TYPE,
> + .header.version = 1,
> + .type = VFIO_REGION_TYPE_MIGRATION,
> + .subtype = VFIO_REGION_SUBTYPE_MIGRATION
> + };
> +
> + /* Add REGION CAP type */
> + ret = vfio_info_add_capability(caps, &cap_type.header,
> + sizeof(cap_type));
> + if (ret)
> + goto exit;
> +
> + /* Add sparse mmap cap type */
> + mig_region.sparse.nr_areas = 1;
> + mig_region.sparse.header.id = VFIO_REGION_INFO_CAP_SPARSE_MMAP;
> + mig_region.sparse.header.version = 1;
> +
> + mig_region.area.offset = MTTY_MIGRATION_REGION_DATA_OFFSET;
> + mig_region.area.size = MTTY_MIGRATION_REGION_SIZE_MMAP;
> +
> + region_info->flags |= VFIO_REGION_INFO_FLAG_CAPS;
> +
> + if (region_info->argsz > sizeof(*region_info))
> + region_info->flags |= VFIO_REGION_INFO_FLAG_MMAP;
> +
> + ret = vfio_info_add_capability(caps, &mig_region.sparse.header,
> + sizeof(mig_region));
> + }
> +exit:
> mutex_unlock(&mdev_state->ops_lock);
> - return 0;
> + return ret;
> }
>
> static int mtty_get_irq_info(struct mdev_device *mdev,
> @@ -1138,7 +1555,7 @@ static int mtty_get_device_info(struct mdev_device *mdev,
> struct vfio_device_info *dev_info)
> {
> dev_info->flags = VFIO_DEVICE_FLAGS_PCI;
> - dev_info->num_regions = VFIO_PCI_NUM_REGIONS;
> + dev_info->num_regions = MTTY_REGIONS_MAX;
> dev_info->num_irqs = VFIO_PCI_NUM_IRQS;
>
> return 0;
> @@ -1150,6 +1567,7 @@ static long mtty_ioctl(struct mdev_device *mdev, unsigned int cmd,
> int ret = 0;
> unsigned long minsz;
> struct mdev_state *mdev_state;
> + struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
>
> if (!mdev)
> return -EINVAL;
> @@ -1185,8 +1603,6 @@ static long mtty_ioctl(struct mdev_device *mdev, unsigned int cmd,
> case VFIO_DEVICE_GET_REGION_INFO:
> {
> struct vfio_region_info info;
> - u16 cap_type_id = 0;
> - void *cap_type = NULL;
>
> minsz = offsetofend(struct vfio_region_info, offset);
>
> @@ -1196,11 +1612,29 @@ static long mtty_ioctl(struct mdev_device *mdev, unsigned int cmd,
> if (info.argsz < minsz)
> return -EINVAL;
>
> - ret = mtty_get_region_info(mdev, &info, &cap_type_id,
> - &cap_type);
> + ret = mtty_get_region_info(mdev, &info, &caps);
> if (ret)
> return ret;
>
> + if (caps.size) {
> + info.flags |= VFIO_REGION_INFO_FLAG_CAPS;
> + if (info.argsz < sizeof(info) + caps.size) {
> + info.argsz = sizeof(info) + caps.size;
> + info.cap_offset = 0;
> + } else {
> + vfio_info_cap_shift(&caps, sizeof(info));
> + if (copy_to_user((void __user *)arg +
> + sizeof(info), caps.buf,
> + caps.size)) {
> + kfree(caps.buf);
> + ret = -EFAULT;
> + break;
> + }
> + info.cap_offset = sizeof(info);
> + }
> + kfree(caps.buf);
> + }
> +
> if (copy_to_user((void __user *)arg, &info, minsz))
> return -EFAULT;
>
> @@ -1266,6 +1700,89 @@ static long mtty_ioctl(struct mdev_device *mdev, unsigned int cmd,
> return -ENOTTY;
> }
>
> +void mmap_close(struct vm_area_struct *vma)
> +{
> + struct mdev_device *mdev = vma->vm_private_data;
> + struct mdev_state *mdev_state;
> + uint32_t index = 0;
> +
> + if (!mdev)
> + return;
> +
> + mdev_state = mdev_get_drvdata(mdev);
> + if (!mdev_state)
> + return;
> +
> + mutex_lock(&mdev_state->ops_lock);
> + index = MTTY_VFIO_PCI_OFFSET_TO_INDEX(vma->vm_pgoff << PAGE_SHIFT);
> + if (index == MTTY_MIGRATION_REGION_INDEX) {
> + if (mdev_state->mig_region_base != NULL) {
> + vfree(mdev_state->mig_region_base);
> + mdev_state->mig_region_base = NULL;
> + }
> +
> + if (mdev_state->pkt != NULL) {
> + vfree(mdev_state->pkt);
> + mdev_state->pkt = NULL;
> + }
> + }
> + mutex_unlock(&mdev_state->ops_lock);
> +}
> +
> +static const struct vm_operations_struct mdev_vm_ops = {
> + .close = mmap_close,
> +};
> +
> +static int mtty_mmap(struct mdev_device *mdev, struct vm_area_struct *vma)
> +{
> + struct mdev_state *mdev_state;
> + unsigned int index;
> + int ret = 0;
> +
> + if (!mdev)
> + return -EINVAL;
> +
> + mdev_state = mdev_get_drvdata(mdev);
> + if (!mdev_state)
> + return -ENODEV;
> +
> + mutex_lock(&mdev_state->ops_lock);
> +
> + index = MTTY_VFIO_PCI_OFFSET_TO_INDEX(vma->vm_pgoff << PAGE_SHIFT);
> + if (index == MTTY_MIGRATION_REGION_INDEX) {
> + mdev_state->mig_region_base =
> + vmalloc_user(MTTY_MIGRATION_REGION_SIZE_MMAP);
> + if (mdev_state->mig_region_base == NULL) {
> + ret = -ENOMEM;
> + goto mmap_exit;
> + }
> +
> + mdev_state->pkt = vzalloc(sizeof(struct packet) +
> + PACKET_DATA_SIZE_MAX);
> + if (mdev_state->pkt == NULL) {
> + vfree(mdev_state->mig_region_base);
> + mdev_state->mig_region_base = NULL;
> + ret = -ENOMEM;
> + goto mmap_exit;
> + }
> +
> + vma->vm_ops = &mdev_vm_ops;
> +
> + ret = remap_vmalloc_range(vma, mdev_state->mig_region_base, 0);
> + if (ret != 0) {
> + pr_err("remap_vmalloc_range failed, ret= %d\n", ret);
> + vfree(mdev_state->mig_region_base);
> + mdev_state->mig_region_base = NULL;
> + vfree(mdev_state->pkt);
> + mdev_state->pkt = NULL;
> + goto mmap_exit;
> + }
> + }
> +mmap_exit:
> + mutex_unlock(&mdev_state->ops_lock);
> + return ret;
> +}
> +
> static void unpin_pages_all(struct mdev_state *mdev_state)
> {
> struct mdev_device *mdev = mdev_state->mdev;
> @@ -1339,6 +1856,8 @@ static int mtty_open(struct mdev_device *mdev)
>
> ret = vfio_register_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, &events,
> &mdev_state->nb);
> + mdev_state->dummy_data_size = 0;
> + mdev_state->mig_region_base = NULL;
> return ret;
> }
>
> @@ -1355,6 +1874,15 @@ static void mtty_close(struct mdev_device *mdev)
> unpin_pages_all(mdev_state);
> vfio_unregister_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY,
> &mdev_state->nb);
> + if (mdev_state->pkt != NULL) {
> + vfree(mdev_state->pkt);
> + mdev_state->pkt = NULL;
> + }
> +
> + if (mdev_state->mig_region_base != NULL) {
> + vfree(mdev_state->mig_region_base);
> + mdev_state->mig_region_base = NULL;
> + }
> }
>
> static ssize_t
> @@ -1466,9 +1994,26 @@ pin_pages_store(struct device *dev, struct device_attribute *attr,
>
> static DEVICE_ATTR_RW(pin_pages);
>
> +static ssize_t
> +dummy_data_size_MB_store(struct device *dev, struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + int ret;
> +
> + ret = kstrtoul(buf, 0, &user_dummy_data_size);
> + if (ret)
> + return ret;
> +
> + user_dummy_data_size = user_dummy_data_size << 20;
> + return count;
> +}
> +
> +static DEVICE_ATTR_WO(dummy_data_size_MB);
> +
> static struct attribute *mdev_dev_attrs[] = {
> &dev_attr_sample_mdev_dev.attr,
> &dev_attr_pin_pages.attr,
> + &dev_attr_dummy_data_size_MB.attr,
> NULL,
> };
>
> @@ -1573,6 +2118,7 @@ static const struct mdev_parent_ops mdev_fops = {
> .read = mtty_read,
> .write = mtty_write,
> .ioctl = mtty_ioctl,
> + .mmap = mtty_mmap,
> };
>
> static void mtty_device_release(struct device *dev)
> --
> 2.7.0
>
--
Dr. David Alan Gilbert / dgilbert@xxxxxxxxxx / Manchester, UK
