Commit 674ebb64 authored by Leon Romanovsky's avatar Leon Romanovsky Committed by Alex Williamson
Browse files

vfio/mlx5: Explicitly use number of pages instead of allocated length 



allocated_length is a multiple of page size and number of pages,
so let's change the functions to accept number of pages. This improves
code readability, simplifies buffer handling, and enables combining DMA
send/receive operations, as will be introduced in the next patches.

Tested-by: default avatarJens Axboe <axboe@kernel.dk>
Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Signed-off-by: default avatarLeon Romanovsky <leonro@nvidia.com>
Acked-by: default avatarYishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/76f39993d2ca0311b3bcfe56038a669d03926815.1747747694.git.leon@kernel.org


Signed-off-by: default avatarAlex Williamson <alex.williamson@redhat.com>
parent 6ef04555

drivers/vfio/pci/mlx5/cmd.c

+16 −16
Original line number Diff line number Diff line
@@ -318,8 +318,7 @@ static int _create_mkey(struct mlx5_core_dev *mdev, u32 pdn, 
			struct mlx5_vhca_recv_buf *recv_buf,

			u32 *mkey)

{

	size_t npages = buf ? DIV_ROUND_UP(buf->allocated_length, PAGE_SIZE) :

				recv_buf->npages;

	size_t npages = buf ? buf->npages : recv_buf->npages;

	int err = 0, inlen;

	__be64 *mtt;

	void *mkc;
@@ -375,7 +374,7 @@ static int mlx5vf_dma_data_buffer(struct mlx5_vhca_data_buffer *buf) 
	if (mvdev->mdev_detach)

		return -ENOTCONN;



	if (buf->dmaed || !buf->allocated_length)

	if (buf->dmaed || !buf->npages)

		return -EINVAL;



	ret = dma_map_sgtable(mdev->device, &buf->table.sgt, buf->dma_dir, 0);
@@ -445,7 +444,7 @@ static int mlx5vf_add_migration_pages(struct mlx5_vhca_data_buffer *buf, 


		if (ret)

			goto err_append;

		buf->allocated_length += filled * PAGE_SIZE;

		buf->npages += filled;

		/* clean input for another bulk allocation */

		memset(page_list, 0, filled * sizeof(*page_list));

		to_fill = min_t(unsigned int, to_alloc,
@@ -464,8 +463,7 @@ static int mlx5vf_add_migration_pages(struct mlx5_vhca_data_buffer *buf, 
}



struct mlx5_vhca_data_buffer *

mlx5vf_alloc_data_buffer(struct mlx5_vf_migration_file *migf,

			 size_t length,

mlx5vf_alloc_data_buffer(struct mlx5_vf_migration_file *migf, u32 npages,

			 enum dma_data_direction dma_dir)

{

	struct mlx5_vhca_data_buffer *buf;
@@ -477,9 +475,8 @@ mlx5vf_alloc_data_buffer(struct mlx5_vf_migration_file *migf, 


	buf->dma_dir = dma_dir;

	buf->migf = migf;

	if (length) {

		ret = mlx5vf_add_migration_pages(buf,

				DIV_ROUND_UP_ULL(length, PAGE_SIZE));

	if (npages) {

		ret = mlx5vf_add_migration_pages(buf, npages);

		if (ret)

			goto end;
@@ -505,8 +502,8 @@ void mlx5vf_put_data_buffer(struct mlx5_vhca_data_buffer *buf) 
}



struct mlx5_vhca_data_buffer *

mlx5vf_get_data_buffer(struct mlx5_vf_migration_file *migf,

		       size_t length, enum dma_data_direction dma_dir)

mlx5vf_get_data_buffer(struct mlx5_vf_migration_file *migf, u32 npages,

		       enum dma_data_direction dma_dir)

{

	struct mlx5_vhca_data_buffer *buf, *temp_buf;

	struct list_head free_list;
@@ -521,7 +518,7 @@ mlx5vf_get_data_buffer(struct mlx5_vf_migration_file *migf, 
	list_for_each_entry_safe(buf, temp_buf, &migf->avail_list, buf_elm) {

		if (buf->dma_dir == dma_dir) {

			list_del_init(&buf->buf_elm);

			if (buf->allocated_length >= length) {

			if (buf->npages >= npages) {

				spin_unlock_irq(&migf->list_lock);

				goto found;

			}
@@ -535,7 +532,7 @@ mlx5vf_get_data_buffer(struct mlx5_vf_migration_file *migf, 
		}

	}

	spin_unlock_irq(&migf->list_lock);

	buf = mlx5vf_alloc_data_buffer(migf, length, dma_dir);

	buf = mlx5vf_alloc_data_buffer(migf, npages, dma_dir);



found:

	while ((temp_buf = list_first_entry_or_null(&free_list,
@@ -716,7 +713,7 @@ int mlx5vf_cmd_save_vhca_state(struct mlx5vf_pci_core_device *mvdev, 
	MLX5_SET(save_vhca_state_in, in, op_mod, 0);

	MLX5_SET(save_vhca_state_in, in, vhca_id, mvdev->vhca_id);

	MLX5_SET(save_vhca_state_in, in, mkey, buf->mkey);

	MLX5_SET(save_vhca_state_in, in, size, buf->allocated_length);

	MLX5_SET(save_vhca_state_in, in, size, buf->npages * PAGE_SIZE);

	MLX5_SET(save_vhca_state_in, in, incremental, inc);

	MLX5_SET(save_vhca_state_in, in, set_track, track);
@@ -738,8 +735,11 @@ int mlx5vf_cmd_save_vhca_state(struct mlx5vf_pci_core_device *mvdev, 
	}



	if (!header_buf) {

		header_buf = mlx5vf_get_data_buffer(migf,

			sizeof(struct mlx5_vf_migration_header), DMA_NONE);

		header_buf = mlx5vf_get_data_buffer(

			migf,

			DIV_ROUND_UP(sizeof(struct mlx5_vf_migration_header),

				     PAGE_SIZE),

			DMA_NONE);

		if (IS_ERR(header_buf)) {

			err = PTR_ERR(header_buf);

			goto err_free;

drivers/vfio/pci/mlx5/cmd.h

+5 −5
Original line number Diff line number Diff line
@@ -56,7 +56,7 @@ struct mlx5_vhca_data_buffer { 
	struct sg_append_table table;

	loff_t start_pos;

	u64 length;

	u64 allocated_length;

	u32 npages;

	u32 mkey;

	enum dma_data_direction dma_dir;

	u8 dmaed:1;
@@ -217,12 +217,12 @@ int mlx5vf_cmd_alloc_pd(struct mlx5_vf_migration_file *migf); 
void mlx5vf_cmd_dealloc_pd(struct mlx5_vf_migration_file *migf);

void mlx5fv_cmd_clean_migf_resources(struct mlx5_vf_migration_file *migf);

struct mlx5_vhca_data_buffer *

mlx5vf_alloc_data_buffer(struct mlx5_vf_migration_file *migf,

			 size_t length, enum dma_data_direction dma_dir);

mlx5vf_alloc_data_buffer(struct mlx5_vf_migration_file *migf, u32 npages,

			 enum dma_data_direction dma_dir);

void mlx5vf_free_data_buffer(struct mlx5_vhca_data_buffer *buf);

struct mlx5_vhca_data_buffer *

mlx5vf_get_data_buffer(struct mlx5_vf_migration_file *migf,

		       size_t length, enum dma_data_direction dma_dir);

mlx5vf_get_data_buffer(struct mlx5_vf_migration_file *migf, u32 npages,

		       enum dma_data_direction dma_dir);

void mlx5vf_put_data_buffer(struct mlx5_vhca_data_buffer *buf);

struct page *mlx5vf_get_migration_page(struct mlx5_vhca_data_buffer *buf,

				       unsigned long offset);

drivers/vfio/pci/mlx5/main.c

+36 −20
Original line number Diff line number Diff line
@@ -308,6 +308,7 @@ static struct mlx5_vhca_data_buffer * 
mlx5vf_mig_file_get_stop_copy_buf(struct mlx5_vf_migration_file *migf,

				  u8 index, size_t required_length)

{

	u32 npages = DIV_ROUND_UP(required_length, PAGE_SIZE);

	struct mlx5_vhca_data_buffer *buf = migf->buf[index];

	u8 chunk_num;
@@ -315,12 +316,11 @@ mlx5vf_mig_file_get_stop_copy_buf(struct mlx5_vf_migration_file *migf, 
	chunk_num = buf->stop_copy_chunk_num;

	buf->migf->buf[index] = NULL;

	/* Checking whether the pre-allocated buffer can fit */

	if (buf->allocated_length >= required_length)

	if (buf->npages >= npages)

		return buf;



	mlx5vf_put_data_buffer(buf);

	buf = mlx5vf_get_data_buffer(buf->migf, required_length,

				     DMA_FROM_DEVICE);

	buf = mlx5vf_get_data_buffer(buf->migf, npages, DMA_FROM_DEVICE);

	if (IS_ERR(buf))

		return buf;
@@ -373,7 +373,8 @@ static int mlx5vf_add_stop_copy_header(struct mlx5_vf_migration_file *migf, 
	u8 *to_buff;

	int ret;



	header_buf = mlx5vf_get_data_buffer(migf, size, DMA_NONE);

	header_buf = mlx5vf_get_data_buffer(migf, DIV_ROUND_UP(size, PAGE_SIZE),

					    DMA_NONE);

	if (IS_ERR(header_buf))

		return PTR_ERR(header_buf);
@@ -388,7 +389,7 @@ static int mlx5vf_add_stop_copy_header(struct mlx5_vf_migration_file *migf, 
	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[0]->allocated_length);

	data.stop_copy_size = cpu_to_le64(migf->buf[0]->npages * PAGE_SIZE);

	memcpy(to_buff + sizeof(header), &data, sizeof(data));

	header_buf->length += sizeof(data);

	kunmap_local(to_buff);
@@ -437,15 +438,20 @@ static int mlx5vf_prep_stop_copy(struct mlx5vf_pci_core_device *mvdev, 


	num_chunks = mvdev->chunk_mode ? MAX_NUM_CHUNKS : 1;

	for (i = 0; i < num_chunks; i++) {

		buf = mlx5vf_get_data_buffer(migf, inc_state_size, DMA_FROM_DEVICE);

		buf = mlx5vf_get_data_buffer(

			migf, DIV_ROUND_UP(inc_state_size, PAGE_SIZE),

			DMA_FROM_DEVICE);

		if (IS_ERR(buf)) {

			ret = PTR_ERR(buf);

			goto err;

		}



		migf->buf[i] = buf;

		buf = mlx5vf_get_data_buffer(migf,

				sizeof(struct mlx5_vf_migration_header), DMA_NONE);

		buf = mlx5vf_get_data_buffer(

			migf,

			DIV_ROUND_UP(sizeof(struct mlx5_vf_migration_header),

				     PAGE_SIZE),

			DMA_NONE);

		if (IS_ERR(buf)) {

			ret = PTR_ERR(buf);

			goto err;
@@ -553,7 +559,8 @@ static long mlx5vf_precopy_ioctl(struct file *filp, unsigned int cmd, 
	 * 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);

	buf = mlx5vf_get_data_buffer(migf, DIV_ROUND_UP(inc_length, PAGE_SIZE),

				     DMA_FROM_DEVICE);

	if (IS_ERR(buf)) {

		ret = PTR_ERR(buf);

		mlx5vf_mark_err(migf);
@@ -675,8 +682,8 @@ mlx5vf_pci_save_device_data(struct mlx5vf_pci_core_device *mvdev, bool track) 


	if (track) {

		/* leave the allocated buffer ready for the stop-copy phase */

		buf = mlx5vf_alloc_data_buffer(migf,

			migf->buf[0]->allocated_length, DMA_FROM_DEVICE);

		buf = mlx5vf_alloc_data_buffer(migf, migf->buf[0]->npages,

					       DMA_FROM_DEVICE);

		if (IS_ERR(buf)) {

			ret = PTR_ERR(buf);

			goto out_pd;
@@ -917,11 +924,14 @@ static ssize_t mlx5vf_resume_write(struct file *filp, const char __user *buf, 
				goto out_unlock;

			break;

		case MLX5_VF_LOAD_STATE_PREP_HEADER_DATA:

			if (vhca_buf_header->allocated_length < migf->record_size) {

		{

			u32 npages = DIV_ROUND_UP(migf->record_size, PAGE_SIZE);



			if (vhca_buf_header->npages < npages) {

				mlx5vf_free_data_buffer(vhca_buf_header);



				migf->buf_header[0] = mlx5vf_alloc_data_buffer(migf,

						migf->record_size, DMA_NONE);

				migf->buf_header[0] = mlx5vf_alloc_data_buffer(

					migf, npages, DMA_NONE);

				if (IS_ERR(migf->buf_header[0])) {

					ret = PTR_ERR(migf->buf_header[0]);

					migf->buf_header[0] = NULL;
@@ -934,6 +944,7 @@ static ssize_t mlx5vf_resume_write(struct file *filp, const char __user *buf, 
			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);
@@ -944,12 +955,13 @@ static ssize_t mlx5vf_resume_write(struct file *filp, const char __user *buf, 
		{

			u64 size = max(migf->record_size,

				       migf->stop_copy_prep_size);

			u32 npages = DIV_ROUND_UP(size, PAGE_SIZE);



			if (vhca_buf->allocated_length < size) {

			if (vhca_buf->npages < npages) {

				mlx5vf_free_data_buffer(vhca_buf);



				migf->buf[0] = mlx5vf_alloc_data_buffer(migf,

							size, DMA_TO_DEVICE);

				migf->buf[0] = mlx5vf_alloc_data_buffer(

					migf, npages, DMA_TO_DEVICE);

				if (IS_ERR(migf->buf[0])) {

					ret = PTR_ERR(migf->buf[0]);

					migf->buf[0] = NULL;
@@ -1037,8 +1049,11 @@ mlx5vf_pci_resume_device_data(struct mlx5vf_pci_core_device *mvdev) 
	}



	migf->buf[0] = buf;

	buf = mlx5vf_alloc_data_buffer(migf,

		sizeof(struct mlx5_vf_migration_header), DMA_NONE);

	buf = mlx5vf_alloc_data_buffer(

		migf,

		DIV_ROUND_UP(sizeof(struct mlx5_vf_migration_header),

			     PAGE_SIZE),

		DMA_NONE);

	if (IS_ERR(buf)) {

		ret = PTR_ERR(buf);

		goto out_buf;
@@ -1148,7 +1163,8 @@ mlx5vf_pci_step_device_state_locked(struct mlx5vf_pci_core_device *mvdev, 
					MLX5VF_QUERY_INC | MLX5VF_QUERY_CLEANUP);

		if (ret)

			return ERR_PTR(ret);

		buf = mlx5vf_get_data_buffer(migf, size, DMA_FROM_DEVICE);

		buf = mlx5vf_get_data_buffer(migf,

				DIV_ROUND_UP(size, PAGE_SIZE), DMA_FROM_DEVICE);

		if (IS_ERR(buf))

			return ERR_CAST(buf);

		/* pre_copy cleanup */