diff mbox series

[v9,vfio,4/7] vfio/pds: Add VFIO live migration support

Message ID 20230422010642.60720-5-brett.creeley@amd.com (mailing list archive)
State New, archived
Headers show
Series pds_vfio driver | expand

Commit Message

Brett Creeley April 22, 2023, 1:06 a.m. UTC
Add live migration support via the VFIO subsystem. The migration
implementation aligns with the definition from uapi/vfio.h and uses
the pds_core PF's adminq for device configuration.

The ability to suspend, resume, and transfer VF device state data is
included along with the required admin queue command structures and
implementations.

PDS_LM_CMD_SUSPEND and PDS_LM_CMD_SUSPEND_STATUS are added to support
the VF device suspend operation.

PDS_LM_CMD_RESUME is added to support the VF device resume operation.

PDS_LM_CMD_STATUS is added to determine the exact size of the VF
device state data.

PDS_LM_CMD_SAVE is added to get the VF device state data.

PDS_LM_CMD_RESTORE is added to restore the VF device with the
previously saved data from PDS_LM_CMD_SAVE.

PDS_LM_CMD_HOST_VF_STATUS is added to notify the device when
a migration is in/not-in progress from the host's perspective.

Signed-off-by: Brett Creeley <brett.creeley@amd.com>
Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
---
 drivers/vfio/pci/pds/Makefile   |   1 +
 drivers/vfio/pci/pds/cmds.c     | 316 +++++++++++++++++++++++
 drivers/vfio/pci/pds/cmds.h     |   8 +-
 drivers/vfio/pci/pds/lm.c       | 437 ++++++++++++++++++++++++++++++++
 drivers/vfio/pci/pds/lm.h       |  41 +++
 drivers/vfio/pci/pds/pci_drv.c  |  15 ++
 drivers/vfio/pci/pds/vfio_dev.c | 127 +++++++++-
 drivers/vfio/pci/pds/vfio_dev.h |  11 +
 include/linux/pds/pds_adminq.h  |  12 +
 include/linux/pds/pds_lm.h      | 206 +++++++++++++++
 10 files changed, 1172 insertions(+), 2 deletions(-)
 create mode 100644 drivers/vfio/pci/pds/lm.c
 create mode 100644 drivers/vfio/pci/pds/lm.h

Comments

Jason Gunthorpe May 4, 2023, 5:34 p.m. UTC | #1
On Fri, Apr 21, 2023 at 06:06:39PM -0700, Brett Creeley wrote:

> +static struct pds_vfio_lm_file *
> +pds_vfio_get_lm_file(const struct file_operations *fops, int flags, u64 size)
> +{
> +	struct pds_vfio_lm_file *lm_file = NULL;
> +	unsigned long long npages;
> +	struct page **pages;
> +	int err = 0;
> +
> +	if (!size)
> +		return NULL;
> +
> +	/* Alloc file structure */
> +	lm_file = kzalloc(sizeof(*lm_file), GFP_KERNEL);
> +	if (!lm_file)
> +		return NULL;
> +
> +	/* Create file */
> +	lm_file->filep = anon_inode_getfile("pds_vfio_lm", fops, lm_file, flags);
> +	if (!lm_file->filep)
> +		goto err_get_file;
> +
> +	stream_open(lm_file->filep->f_inode, lm_file->filep);
> +	mutex_init(&lm_file->lock);
> +
> +	lm_file->size = size;
> +
> +	/* Allocate memory for file pages */
> +	npages = DIV_ROUND_UP_ULL(lm_file->size, PAGE_SIZE);
> +
> +	pages = kcalloc(npages, sizeof(*pages), GFP_KERNEL);
> +	if (!pages)
> +		goto err_alloc_pages;
> +
> +	for (unsigned long long i = 0; i < npages; i++) {
> +		pages[i] = alloc_page(GFP_KERNEL);
> +		if (!pages[i])
> +			goto err_alloc_page;
> +	}
> +
> +	lm_file->pages = pages;
> +	lm_file->npages = npages;
> +	lm_file->alloc_size = npages * PAGE_SIZE;
> +
> +	/* Create scatterlist of file pages to use for DMA mapping later */
> +	err = sg_alloc_table_from_pages(&lm_file->sg_table, pages, npages,
> +					0, size, GFP_KERNEL);
> +	if (err)
> +		goto err_alloc_sg_table;
> +
> +	/* prevent file from being released before we are done with it */
> +	get_file(lm_file->filep);
> +
> +	return lm_file;
> +
> +err_alloc_sg_table:
> +err_alloc_page:

What is with these double error out labels? I see it in a few places,
that is not the kernel style.

In VFIO we have been trying to label the err outs based on what they
free, it is not a 'call from' scheme.

Jason
Jason Gunthorpe May 4, 2023, 5:40 p.m. UTC | #2
On Fri, Apr 21, 2023 at 06:06:39PM -0700, Brett Creeley wrote:

> +static struct pds_vfio_lm_file *
> +pds_vfio_get_lm_file(const struct file_operations *fops, int flags, u64 size)
> +{

I see this function is called with a hardwired 64k size on restore -
so this means save is also limited to 64k?

This is really overcomplicated if that is the state size you are
working with - the mlx5 code this was copied from is dealing with much
larger values.

Just kvalloc() your 64k and be done with it. You need a bit of fussing
to DMA map the vmap, but it is much simpler than all of this
stuff. See fpga_mgr_buf_load()

Since the kvalloc is linear the read/write is just memcpy.

Jason
Jason Gunthorpe May 4, 2023, 5:50 p.m. UTC | #3
On Fri, Apr 21, 2023 at 06:06:39PM -0700, Brett Creeley wrote:

> +static int
> +pds_vfio_dma_map_lm_file(struct device *dev, enum dma_data_direction dir,
> +			 struct pds_vfio_lm_file *lm_file)
> +{
> +	struct pds_lm_sg_elem *sgl, *sge;
> +	struct scatterlist *sg;
> +	dma_addr_t sgl_addr;
> +	size_t sgl_size;
> +	int err;
> +	int i;
> +
> +	if (!lm_file)
> +		return -EINVAL;
> +
> +	/* dma map file pages */
> +	err = dma_map_sgtable(dev, &lm_file->sg_table, dir, 0);
> +	if (err)
> +		return err;
> +
> +	lm_file->num_sge = lm_file->sg_table.nents;
> +
> +	/* alloc sgl */
> +	sgl_size = lm_file->num_sge * sizeof(struct pds_lm_sg_elem);
> +	sgl = kzalloc(sgl_size, GFP_KERNEL);
> +	if (!sgl) {
> +		err = -ENOMEM;
> +		goto err_alloc_sgl;
> +	}
> +
> +	sgl_addr = dma_map_single(dev, sgl, sgl_size, DMA_TO_DEVICE);
> +	if (dma_mapping_error(dev, sgl_addr)) {
> +		err = -EIO;
> +		goto err_map_sgl;
> +	}
> +
> +	lm_file->sgl = sgl;
> +	lm_file->sgl_addr = sgl_addr;
> +
> +	/* fill sgl */
> +	sge = sgl;
> +	for_each_sgtable_dma_sg(&lm_file->sg_table, sg, i) {
> +		sge->addr = cpu_to_le64(sg_dma_address(sg));
> +		sge->len  = cpu_to_le32(sg_dma_len(sg));
> +		dev_dbg(dev, "addr = %llx, len = %u\n", sge->addr, sge->len);
> +		sge++;
> +	}

This sequence is in the wrong order, the dma_map_single() has to be
after the data is written to the memory as it synchronizes the caches
on some arches

> +
> +	return 0;
> +
> +err_map_sgl:
> +	kfree(sgl);
> +err_alloc_sgl:
> +	dma_unmap_sgtable(dev, &lm_file->sg_table, dir, 0);
> +	return err;

And why is the goto error unwind in a messed up order? Error unwinds
should always be strictly in the opposite order of the success
path. Check them all when you are fixing the "come from" notation

Jason
Brett Creeley May 5, 2023, 3:37 p.m. UTC | #4
On 5/4/2023 10:34 AM, Jason Gunthorpe wrote:
> Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.
> 
> 
> On Fri, Apr 21, 2023 at 06:06:39PM -0700, Brett Creeley wrote:
> 
>> +static struct pds_vfio_lm_file *
>> +pds_vfio_get_lm_file(const struct file_operations *fops, int flags, u64 size)
>> +{
>> +     struct pds_vfio_lm_file *lm_file = NULL;
>> +     unsigned long long npages;
>> +     struct page **pages;
>> +     int err = 0;
>> +
>> +     if (!size)
>> +             return NULL;
>> +
>> +     /* Alloc file structure */
>> +     lm_file = kzalloc(sizeof(*lm_file), GFP_KERNEL);
>> +     if (!lm_file)
>> +             return NULL;
>> +
>> +     /* Create file */
>> +     lm_file->filep = anon_inode_getfile("pds_vfio_lm", fops, lm_file, flags);
>> +     if (!lm_file->filep)
>> +             goto err_get_file;
>> +
>> +     stream_open(lm_file->filep->f_inode, lm_file->filep);
>> +     mutex_init(&lm_file->lock);
>> +
>> +     lm_file->size = size;
>> +
>> +     /* Allocate memory for file pages */
>> +     npages = DIV_ROUND_UP_ULL(lm_file->size, PAGE_SIZE);
>> +
>> +     pages = kcalloc(npages, sizeof(*pages), GFP_KERNEL);
>> +     if (!pages)
>> +             goto err_alloc_pages;
>> +
>> +     for (unsigned long long i = 0; i < npages; i++) {
>> +             pages[i] = alloc_page(GFP_KERNEL);
>> +             if (!pages[i])
>> +                     goto err_alloc_page;
>> +     }
>> +
>> +     lm_file->pages = pages;
>> +     lm_file->npages = npages;
>> +     lm_file->alloc_size = npages * PAGE_SIZE;
>> +
>> +     /* Create scatterlist of file pages to use for DMA mapping later */
>> +     err = sg_alloc_table_from_pages(&lm_file->sg_table, pages, npages,
>> +                                     0, size, GFP_KERNEL);
>> +     if (err)
>> +             goto err_alloc_sg_table;
>> +
>> +     /* prevent file from being released before we are done with it */
>> +     get_file(lm_file->filep);
>> +
>> +     return lm_file;
>> +
>> +err_alloc_sg_table:
>> +err_alloc_page:
> 
> What is with these double error out labels? I see it in a few places,
> that is not the kernel style.
> 
> In VFIO we have been trying to label the err outs based on what they
> free, it is not a 'call from' scheme.
> 
> Jason

Yeah this is kind of ugly. Thanks for pointing it out. I will fix it and 
any other occurrences in the next revision.

Brett
Brett Creeley May 5, 2023, 3:39 p.m. UTC | #5
On 5/4/2023 10:40 AM, Jason Gunthorpe wrote:
> Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.
> 
> 
> On Fri, Apr 21, 2023 at 06:06:39PM -0700, Brett Creeley wrote:
> 
>> +static struct pds_vfio_lm_file *
>> +pds_vfio_get_lm_file(const struct file_operations *fops, int flags, u64 size)
>> +{
> 
> I see this function is called with a hardwired 64k size on restore -
> so this means save is also limited to 64k?
> 
> This is really overcomplicated if that is the state size you are
> working with - the mlx5 code this was copied from is dealing with much
> larger values.
> 
> Just kvalloc() your 64k and be done with it. You need a bit of fussing
> to DMA map the vmap, but it is much simpler than all of this
> stuff. See fpga_mgr_buf_load()
> 
> Since the kvalloc is linear the read/write is just memcpy.
> 
> Jason

My only thought here is that if we ever need to support a larger device 
state size in the future we may have to revisit this implementation once 
again.

I will look into this before pushing the next revision. Thanks for the 
example/pointer to fpga_mgr_buf_load() and for the review.

Brett
Brett Creeley May 5, 2023, 3:42 p.m. UTC | #6
On 5/4/2023 10:50 AM, Jason Gunthorpe wrote:
> Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.
> 
> 
> On Fri, Apr 21, 2023 at 06:06:39PM -0700, Brett Creeley wrote:
> 
>> +static int
>> +pds_vfio_dma_map_lm_file(struct device *dev, enum dma_data_direction dir,
>> +                      struct pds_vfio_lm_file *lm_file)
>> +{
>> +     struct pds_lm_sg_elem *sgl, *sge;
>> +     struct scatterlist *sg;
>> +     dma_addr_t sgl_addr;
>> +     size_t sgl_size;
>> +     int err;
>> +     int i;
>> +
>> +     if (!lm_file)
>> +             return -EINVAL;
>> +
>> +     /* dma map file pages */
>> +     err = dma_map_sgtable(dev, &lm_file->sg_table, dir, 0);
>> +     if (err)
>> +             return err;
>> +
>> +     lm_file->num_sge = lm_file->sg_table.nents;
>> +
>> +     /* alloc sgl */
>> +     sgl_size = lm_file->num_sge * sizeof(struct pds_lm_sg_elem);
>> +     sgl = kzalloc(sgl_size, GFP_KERNEL);
>> +     if (!sgl) {
>> +             err = -ENOMEM;
>> +             goto err_alloc_sgl;
>> +     }
>> +
>> +     sgl_addr = dma_map_single(dev, sgl, sgl_size, DMA_TO_DEVICE);
>> +     if (dma_mapping_error(dev, sgl_addr)) {
>> +             err = -EIO;
>> +             goto err_map_sgl;
>> +     }
>> +
>> +     lm_file->sgl = sgl;
>> +     lm_file->sgl_addr = sgl_addr;
>> +
>> +     /* fill sgl */
>> +     sge = sgl;
>> +     for_each_sgtable_dma_sg(&lm_file->sg_table, sg, i) {
>> +             sge->addr = cpu_to_le64(sg_dma_address(sg));
>> +             sge->len  = cpu_to_le32(sg_dma_len(sg));
>> +             dev_dbg(dev, "addr = %llx, len = %u\n", sge->addr, sge->len);
>> +             sge++;
>> +     }
> 
> This sequence is in the wrong order, the dma_map_single() has to be
> after the data is written to the memory as it synchronizes the caches
> on some arches

This is an easy enough fix and I'll keep this in mind moving forward. 
Thanks for pointing it out.

> 
>> +
>> +     return 0;
>> +
>> +err_map_sgl:
>> +     kfree(sgl);
>> +err_alloc_sgl:
>> +     dma_unmap_sgtable(dev, &lm_file->sg_table, dir, 0);
>> +     return err;
> 
> And why is the goto error unwind in a messed up order? Error unwinds
> should always be strictly in the opposite order of the success
> path. Check them all when you are fixing the "come from" notation
> 
> Jason

Yeah, this wasn't on purpose. Thanks again for pointing things like this 
out. As you noted I will go through the entire series to make sure the 
goto labels are named by what they are freeing/clearing and also that 
they are in the correct opposite order.

Thanks again for the review.

Brett
diff mbox series

Patch

diff --git a/drivers/vfio/pci/pds/Makefile b/drivers/vfio/pci/pds/Makefile
index 87581111fa17..dbaf613d3794 100644
--- a/drivers/vfio/pci/pds/Makefile
+++ b/drivers/vfio/pci/pds/Makefile
@@ -5,5 +5,6 @@  obj-$(CONFIG_PDS_VFIO_PCI) += pds_vfio.o
 
 pds_vfio-y := \
 	cmds.o		\
+	lm.o		\
 	pci_drv.o	\
 	vfio_dev.o
diff --git a/drivers/vfio/pci/pds/cmds.c b/drivers/vfio/pci/pds/cmds.c
index 29a350cb5df5..b51873dace96 100644
--- a/drivers/vfio/pci/pds/cmds.c
+++ b/drivers/vfio/pci/pds/cmds.c
@@ -3,6 +3,7 @@ 
 
 #include <linux/io.h>
 #include <linux/types.h>
+#include <linux/delay.h>
 
 #include <linux/pds/pds_common.h>
 #include <linux/pds/pds_core_if.h>
@@ -12,6 +13,35 @@ 
 #include "vfio_dev.h"
 #include "cmds.h"
 
+#define SUSPEND_TIMEOUT_S		5
+#define SUSPEND_CHECK_INTERVAL_MS	1
+
+static int
+pds_vfio_client_adminq_cmd(struct pds_vfio_pci_device *pds_vfio,
+			   union pds_core_adminq_cmd *req,
+			   size_t req_len,
+			   union pds_core_adminq_comp *resp,
+			   u64 flags)
+{
+	union pds_core_adminq_cmd cmd = {};
+	size_t cp_len;
+	int err;
+
+	/* Wrap the client request */
+	cmd.client_request.opcode = PDS_AQ_CMD_CLIENT_CMD;
+	cmd.client_request.client_id = cpu_to_le16(pds_vfio->client_id);
+	cp_len = min_t(size_t, req_len, sizeof(cmd.client_request.client_cmd));
+	memcpy(cmd.client_request.client_cmd, req, cp_len);
+
+	err = pdsc_adminq_post(pds_vfio->pdsc, &cmd, resp,
+			       !!(flags & PDS_AQ_FLAG_FASTPOLL));
+	if (err && err != -EAGAIN)
+		dev_info(pds_vfio_to_dev(pds_vfio), "client admin cmd failed: %pe\n",
+			 ERR_PTR(err));
+
+	return err;
+}
+
 int
 pds_vfio_register_client_cmd(struct pds_vfio_pci_device *pds_vfio)
 {
@@ -45,3 +75,289 @@  pds_vfio_unregister_client_cmd(struct pds_vfio_pci_device *pds_vfio)
 
 	pds_vfio->client_id = 0;
 }
+
+static int
+pds_vfio_suspend_wait_device_cmd(struct pds_vfio_pci_device *pds_vfio)
+{
+	union pds_core_adminq_cmd cmd = {
+		.lm_suspend_status.opcode = PDS_LM_CMD_SUSPEND_STATUS,
+		.lm_suspend_status.vf_id = cpu_to_le16(pds_vfio->vf_id),
+	};
+	struct device *dev = pds_vfio_to_dev(pds_vfio);
+	union pds_core_adminq_comp comp = {};
+	unsigned long time_limit;
+	unsigned long time_start;
+	unsigned long time_done;
+	int err;
+
+	time_start = jiffies;
+	time_limit = time_start + HZ * SUSPEND_TIMEOUT_S;
+	do {
+		err = pds_vfio_client_adminq_cmd(pds_vfio, &cmd, sizeof(cmd),
+						 &comp, PDS_AQ_FLAG_FASTPOLL);
+		if (err != -EAGAIN)
+			break;
+
+		msleep(SUSPEND_CHECK_INTERVAL_MS);
+	} while (time_before(jiffies, time_limit));
+
+	time_done = jiffies;
+	dev_dbg(dev, "%s: vf%u: Suspend comp received in %d msecs\n",
+		__func__, pds_vfio->vf_id,
+		jiffies_to_msecs(time_done - time_start));
+
+	/* Check the results */
+	if (time_after_eq(time_done, time_limit)) {
+		dev_err(dev, "%s: vf%u: Suspend comp timeout\n", __func__,
+			pds_vfio->vf_id);
+		err = -ETIMEDOUT;
+	}
+
+	return err;
+}
+
+int
+pds_vfio_suspend_device_cmd(struct pds_vfio_pci_device *pds_vfio)
+{
+	union pds_core_adminq_cmd cmd = {
+		.lm_suspend.opcode = PDS_LM_CMD_SUSPEND,
+		.lm_suspend.vf_id = cpu_to_le16(pds_vfio->vf_id),
+	};
+	struct device *dev = pds_vfio_to_dev(pds_vfio);
+	union pds_core_adminq_comp comp = {};
+	int err;
+
+	dev_dbg(dev, "vf%u: Suspend device\n", pds_vfio->vf_id);
+
+	err = pds_vfio_client_adminq_cmd(pds_vfio, &cmd, sizeof(cmd),
+					 &comp, PDS_AQ_FLAG_FASTPOLL);
+	if (err) {
+		dev_err(dev, "vf%u: Suspend failed: %pe\n",
+			pds_vfio->vf_id, ERR_PTR(err));
+		return err;
+	}
+
+	return pds_vfio_suspend_wait_device_cmd(pds_vfio);
+}
+
+int
+pds_vfio_resume_device_cmd(struct pds_vfio_pci_device *pds_vfio)
+{
+	union pds_core_adminq_cmd cmd = {
+		.lm_resume.opcode = PDS_LM_CMD_RESUME,
+		.lm_resume.vf_id = cpu_to_le16(pds_vfio->vf_id),
+	};
+	struct device *dev = pds_vfio_to_dev(pds_vfio);
+	union pds_core_adminq_comp comp = {};
+
+	dev_dbg(dev, "vf%u: Resume device\n", pds_vfio->vf_id);
+
+	return pds_vfio_client_adminq_cmd(pds_vfio, &cmd, sizeof(cmd),
+					  &comp, 0);
+}
+
+int
+pds_vfio_get_lm_status_cmd(struct pds_vfio_pci_device *pds_vfio, u64 *size)
+{
+	union pds_core_adminq_cmd cmd = {
+		.lm_status.opcode = PDS_LM_CMD_STATUS,
+		.lm_status.vf_id = cpu_to_le16(pds_vfio->vf_id),
+	};
+	struct device *dev = pds_vfio_to_dev(pds_vfio);
+	union pds_core_adminq_comp comp = {};
+	int err;
+
+	dev_dbg(dev, "vf%u: Get migration status\n",
+		pds_vfio->vf_id);
+
+	err = pds_vfio_client_adminq_cmd(pds_vfio, &cmd, sizeof(cmd),
+					 &comp, 0);
+	if (err)
+		return err;
+
+	*size = le64_to_cpu(comp.lm_status.size);
+	return 0;
+}
+
+static int
+pds_vfio_dma_map_lm_file(struct device *dev, enum dma_data_direction dir,
+			 struct pds_vfio_lm_file *lm_file)
+{
+	struct pds_lm_sg_elem *sgl, *sge;
+	struct scatterlist *sg;
+	dma_addr_t sgl_addr;
+	size_t sgl_size;
+	int err;
+	int i;
+
+	if (!lm_file)
+		return -EINVAL;
+
+	/* dma map file pages */
+	err = dma_map_sgtable(dev, &lm_file->sg_table, dir, 0);
+	if (err)
+		return err;
+
+	lm_file->num_sge = lm_file->sg_table.nents;
+
+	/* alloc sgl */
+	sgl_size = lm_file->num_sge * sizeof(struct pds_lm_sg_elem);
+	sgl = kzalloc(sgl_size, GFP_KERNEL);
+	if (!sgl) {
+		err = -ENOMEM;
+		goto err_alloc_sgl;
+	}
+
+	sgl_addr = dma_map_single(dev, sgl, sgl_size, DMA_TO_DEVICE);
+	if (dma_mapping_error(dev, sgl_addr)) {
+		err = -EIO;
+		goto err_map_sgl;
+	}
+
+	lm_file->sgl = sgl;
+	lm_file->sgl_addr = sgl_addr;
+
+	/* fill sgl */
+	sge = sgl;
+	for_each_sgtable_dma_sg(&lm_file->sg_table, sg, i) {
+		sge->addr = cpu_to_le64(sg_dma_address(sg));
+		sge->len  = cpu_to_le32(sg_dma_len(sg));
+		dev_dbg(dev, "addr = %llx, len = %u\n", sge->addr, sge->len);
+		sge++;
+	}
+
+	return 0;
+
+err_map_sgl:
+	kfree(sgl);
+err_alloc_sgl:
+	dma_unmap_sgtable(dev, &lm_file->sg_table, dir, 0);
+	return err;
+}
+
+static void
+pds_vfio_dma_unmap_lm_file(struct device *dev, enum dma_data_direction dir,
+			   struct pds_vfio_lm_file *lm_file)
+{
+	if (!lm_file)
+		return;
+
+	/* free sgl */
+	if (lm_file->sgl) {
+		dma_unmap_single(dev, lm_file->sgl_addr,
+				 lm_file->num_sge * sizeof(struct pds_lm_sg_elem),
+				 DMA_TO_DEVICE);
+		kfree(lm_file->sgl);
+		lm_file->sgl = NULL;
+		lm_file->sgl_addr = DMA_MAPPING_ERROR;
+		lm_file->num_sge = 0;
+	}
+
+	/* dma unmap file pages */
+	dma_unmap_sgtable(dev, &lm_file->sg_table, dir, 0);
+}
+
+int
+pds_vfio_get_lm_state_cmd(struct pds_vfio_pci_device *pds_vfio)
+{
+	union pds_core_adminq_cmd cmd = {
+		.lm_save.opcode = PDS_LM_CMD_SAVE,
+		.lm_save.vf_id = cpu_to_le16(pds_vfio->vf_id),
+	};
+	struct pci_dev *pdev = pds_vfio_to_pci_dev(pds_vfio);
+	struct device *pdsc_dev = &pci_physfn(pdev)->dev;
+	union pds_core_adminq_comp comp = {};
+	struct pds_vfio_lm_file *lm_file;
+	int err;
+
+	dev_dbg(&pdev->dev, "vf%u: Get migration state\n", pds_vfio->vf_id);
+
+	lm_file = pds_vfio->save_file;
+
+	err = pds_vfio_dma_map_lm_file(pdsc_dev, DMA_FROM_DEVICE, lm_file);
+	if (err) {
+		dev_err(&pdev->dev, "failed to map save migration file: %pe\n",
+			ERR_PTR(err));
+		return err;
+	}
+
+	cmd.lm_save.sgl_addr = cpu_to_le64(lm_file->sgl_addr);
+	cmd.lm_save.num_sge = cpu_to_le32(lm_file->num_sge);
+
+	err = pds_vfio_client_adminq_cmd(pds_vfio, &cmd, sizeof(cmd),
+					 &comp, 0);
+	if (err)
+		dev_err(&pdev->dev, "failed to get migration state: %pe\n",
+			ERR_PTR(err));
+
+	pds_vfio_dma_unmap_lm_file(pdsc_dev, DMA_FROM_DEVICE, lm_file);
+
+	return err;
+}
+
+int
+pds_vfio_set_lm_state_cmd(struct pds_vfio_pci_device *pds_vfio)
+{
+	union pds_core_adminq_cmd cmd = {
+		.lm_restore.opcode = PDS_LM_CMD_RESTORE,
+		.lm_restore.vf_id = cpu_to_le16(pds_vfio->vf_id),
+	};
+	struct pci_dev *pdev = pds_vfio_to_pci_dev(pds_vfio);
+	struct device *pdsc_dev = &pci_physfn(pdev)->dev;
+	union pds_core_adminq_comp comp = {};
+	struct pds_vfio_lm_file *lm_file;
+	int err;
+
+	dev_dbg(&pdev->dev, "vf%u: Set migration state\n", pds_vfio->vf_id);
+
+	lm_file = pds_vfio->restore_file;
+
+	err = pds_vfio_dma_map_lm_file(pdsc_dev, DMA_TO_DEVICE, lm_file);
+	if (err) {
+		dev_err(&pdev->dev, "failed to map restore migration file: %pe\n",
+			ERR_PTR(err));
+		return err;
+	}
+
+	cmd.lm_restore.sgl_addr = cpu_to_le64(lm_file->sgl_addr);
+	cmd.lm_restore.num_sge = cpu_to_le32(lm_file->num_sge);
+
+	err = pds_vfio_client_adminq_cmd(pds_vfio, &cmd, sizeof(cmd),
+					 &comp, 0);
+	if (err)
+		dev_err(&pdev->dev, "failed to set migration state: %pe\n",
+			ERR_PTR(err));
+
+	pds_vfio_dma_unmap_lm_file(pdsc_dev, DMA_TO_DEVICE, lm_file);
+
+	return err;
+}
+
+void
+pds_vfio_send_host_vf_lm_status_cmd(struct pds_vfio_pci_device *pds_vfio,
+				    enum pds_lm_host_vf_status vf_status)
+{
+	union pds_core_adminq_cmd cmd = {
+		.lm_host_vf_status.opcode = PDS_LM_CMD_HOST_VF_STATUS,
+		.lm_host_vf_status.vf_id = cpu_to_le16(pds_vfio->vf_id),
+		.lm_host_vf_status.status = vf_status,
+	};
+	struct device *dev = pds_vfio_to_dev(pds_vfio);
+	union pds_core_adminq_comp comp = {};
+	int err;
+
+	dev_dbg(dev, "vf%u: Set host VF LM status: %u",
+		pds_vfio->vf_id, vf_status);
+	if (vf_status != PDS_LM_STA_IN_PROGRESS &&
+	    vf_status != PDS_LM_STA_NONE) {
+		dev_warn(dev, "Invalid host VF migration status, %d\n",
+			 vf_status);
+		return;
+	}
+
+	err = pds_vfio_client_adminq_cmd(pds_vfio, &cmd, sizeof(cmd),
+					 &comp, 0);
+	if (err)
+		dev_warn(dev, "failed to send host VF migration status: %pe\n",
+			 ERR_PTR(err));
+}
diff --git a/drivers/vfio/pci/pds/cmds.h b/drivers/vfio/pci/pds/cmds.h
index 4c592afccf89..3d8a5508c733 100644
--- a/drivers/vfio/pci/pds/cmds.h
+++ b/drivers/vfio/pci/pds/cmds.h
@@ -6,5 +6,11 @@ 
 
 int pds_vfio_register_client_cmd(struct pds_vfio_pci_device *pds_vfio);
 void pds_vfio_unregister_client_cmd(struct pds_vfio_pci_device *pds_vfio);
-
+int pds_vfio_suspend_device_cmd(struct pds_vfio_pci_device *pds_vfio);
+int pds_vfio_resume_device_cmd(struct pds_vfio_pci_device *pds_vfio);
+int pds_vfio_get_lm_status_cmd(struct pds_vfio_pci_device *pds_vfio, u64 *size);
+int pds_vfio_get_lm_state_cmd(struct pds_vfio_pci_device *pds_vfio);
+int pds_vfio_set_lm_state_cmd(struct pds_vfio_pci_device *pds_vfio);
+void pds_vfio_send_host_vf_lm_status_cmd(struct pds_vfio_pci_device *pds_vfio,
+					 enum pds_lm_host_vf_status vf_status);
 #endif /* _CMDS_H_ */
diff --git a/drivers/vfio/pci/pds/lm.c b/drivers/vfio/pci/pds/lm.c
new file mode 100644
index 000000000000..4e736f415df2
--- /dev/null
+++ b/drivers/vfio/pci/pds/lm.c
@@ -0,0 +1,437 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2023 Advanced Micro Devices, Inc. */
+
+#include <linux/anon_inodes.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/highmem.h>
+#include <linux/vfio.h>
+#include <linux/vfio_pci_core.h>
+
+#include "vfio_dev.h"
+#include "cmds.h"
+
+static struct pds_vfio_lm_file *
+pds_vfio_get_lm_file(const struct file_operations *fops, int flags, u64 size)
+{
+	struct pds_vfio_lm_file *lm_file = NULL;
+	unsigned long long npages;
+	struct page **pages;
+	int err = 0;
+
+	if (!size)
+		return NULL;
+
+	/* Alloc file structure */
+	lm_file = kzalloc(sizeof(*lm_file), GFP_KERNEL);
+	if (!lm_file)
+		return NULL;
+
+	/* Create file */
+	lm_file->filep = anon_inode_getfile("pds_vfio_lm", fops, lm_file, flags);
+	if (!lm_file->filep)
+		goto err_get_file;
+
+	stream_open(lm_file->filep->f_inode, lm_file->filep);
+	mutex_init(&lm_file->lock);
+
+	lm_file->size = size;
+
+	/* Allocate memory for file pages */
+	npages = DIV_ROUND_UP_ULL(lm_file->size, PAGE_SIZE);
+
+	pages = kcalloc(npages, sizeof(*pages), GFP_KERNEL);
+	if (!pages)
+		goto err_alloc_pages;
+
+	for (unsigned long long i = 0; i < npages; i++) {
+		pages[i] = alloc_page(GFP_KERNEL);
+		if (!pages[i])
+			goto err_alloc_page;
+	}
+
+	lm_file->pages = pages;
+	lm_file->npages = npages;
+	lm_file->alloc_size = npages * PAGE_SIZE;
+
+	/* Create scatterlist of file pages to use for DMA mapping later */
+	err = sg_alloc_table_from_pages(&lm_file->sg_table, pages, npages,
+					0, size, GFP_KERNEL);
+	if (err)
+		goto err_alloc_sg_table;
+
+	/* prevent file from being released before we are done with it */
+	get_file(lm_file->filep);
+
+	return lm_file;
+
+err_alloc_sg_table:
+err_alloc_page:
+	/* free allocated pages */
+	for (unsigned long long i = 0; i < npages && pages[i]; i++)
+		__free_page(pages[i]);
+	kfree(pages);
+err_alloc_pages:
+	fput(lm_file->filep);
+	mutex_destroy(&lm_file->lock);
+err_get_file:
+	kfree(lm_file);
+
+	return NULL;
+}
+
+static void
+pds_vfio_put_lm_file(struct pds_vfio_lm_file *lm_file)
+{
+	mutex_lock(&lm_file->lock);
+
+	lm_file->size = 0;
+	lm_file->alloc_size = 0;
+
+	/* Free scatter list of file pages */
+	sg_free_table(&lm_file->sg_table);
+
+	/* Free allocated file pages */
+	for (unsigned long long i = 0;
+	     i < lm_file->npages && lm_file->pages[i]; i++)
+		__free_page(lm_file->pages[i]);
+	kfree(lm_file->pages);
+	lm_file->pages = NULL;
+
+	mutex_unlock(&lm_file->lock);
+
+	/* allow file to be released since we are done with it */
+	fput(lm_file->filep);
+}
+
+void
+pds_vfio_put_save_file(struct pds_vfio_pci_device *pds_vfio)
+{
+	if (!pds_vfio->save_file)
+		return;
+
+	pds_vfio_put_lm_file(pds_vfio->save_file);
+	pds_vfio->save_file = NULL;
+}
+
+void
+pds_vfio_put_restore_file(struct pds_vfio_pci_device *pds_vfio)
+{
+	if (!pds_vfio->restore_file)
+		return;
+
+	pds_vfio_put_lm_file(pds_vfio->restore_file);
+	pds_vfio->restore_file = NULL;
+}
+
+static struct page *
+pds_vfio_get_file_page(struct pds_vfio_lm_file *lm_file,
+		       unsigned long offset)
+{
+	unsigned long cur_offset = 0;
+	struct scatterlist *sg;
+	unsigned int i;
+
+	/* All accesses are sequential */
+	if (offset < lm_file->last_offset || !lm_file->last_offset_sg) {
+		lm_file->last_offset = 0;
+		lm_file->last_offset_sg = lm_file->sg_table.sgl;
+		lm_file->sg_last_entry = 0;
+	}
+
+	cur_offset = lm_file->last_offset;
+
+	for_each_sg(lm_file->last_offset_sg, sg,
+		    lm_file->sg_table.orig_nents - lm_file->sg_last_entry,
+		    i) {
+		if (offset < sg->length + cur_offset) {
+			lm_file->last_offset_sg = sg;
+			lm_file->sg_last_entry += i;
+			lm_file->last_offset = cur_offset;
+			return nth_page(sg_page(sg),
+					(offset - cur_offset) / PAGE_SIZE);
+		}
+		cur_offset += sg->length;
+	}
+
+	return NULL;
+}
+
+static int
+pds_vfio_release_file(struct inode *inode, struct file *filp)
+{
+	struct pds_vfio_lm_file *lm_file = filp->private_data;
+
+	mutex_lock(&lm_file->lock);
+	lm_file->filep->f_pos = 0;
+	lm_file->size = 0;
+	mutex_unlock(&lm_file->lock);
+	mutex_destroy(&lm_file->lock);
+	kfree(lm_file);
+
+	return 0;
+}
+
+static ssize_t
+pds_vfio_save_read(struct file *filp, char __user *buf, size_t len, loff_t *pos)
+{
+	struct pds_vfio_lm_file *lm_file = filp->private_data;
+	ssize_t done = 0;
+
+	if (pos)
+		return -ESPIPE;
+	pos = &filp->f_pos;
+
+	mutex_lock(&lm_file->lock);
+	if (*pos > lm_file->size) {
+		done = -EINVAL;
+		goto out_unlock;
+	}
+
+	len = min_t(size_t, lm_file->size - *pos, len);
+	while (len) {
+		size_t page_offset;
+		struct page *page;
+		size_t page_len;
+		u8 *from_buff;
+		int err;
+
+		page_offset = (*pos) % PAGE_SIZE;
+		page = pds_vfio_get_file_page(lm_file, *pos - page_offset);
+		if (!page) {
+			if (done == 0)
+				done = -EINVAL;
+			goto out_unlock;
+		}
+
+		page_len = min_t(size_t, len, PAGE_SIZE - page_offset);
+		from_buff = kmap_local_page(page);
+		err = copy_to_user(buf, from_buff + page_offset, page_len);
+		kunmap_local(from_buff);
+		if (err) {
+			done = -EFAULT;
+			goto out_unlock;
+		}
+		*pos += page_len;
+		len -= page_len;
+		done += page_len;
+		buf += page_len;
+	}
+
+out_unlock:
+	mutex_unlock(&lm_file->lock);
+	return done;
+}
+
+static const struct file_operations
+pds_vfio_save_fops = {
+	.owner = THIS_MODULE,
+	.read = pds_vfio_save_read,
+	.release = pds_vfio_release_file,
+	.llseek = no_llseek,
+};
+
+static int
+pds_vfio_get_save_file(struct pds_vfio_pci_device *pds_vfio)
+{
+	struct device *dev = &pds_vfio->vfio_coredev.pdev->dev;
+	struct pds_vfio_lm_file *lm_file;
+	int err;
+	u64 size;
+
+	/* Get live migration state size in this state */
+	err = pds_vfio_get_lm_status_cmd(pds_vfio, &size);
+	if (err) {
+		dev_err(dev, "failed to get save status: %pe\n",
+			ERR_PTR(err));
+		return err;
+	}
+
+	dev_dbg(dev, "save status, size = %lld\n", size);
+
+	if (!size) {
+		dev_err(dev, "invalid state size\n");
+		return -EIO;
+	}
+
+	lm_file = pds_vfio_get_lm_file(&pds_vfio_save_fops,
+				       O_RDONLY, size);
+	if (!lm_file) {
+		dev_err(dev, "failed to create save file\n");
+		return -ENOENT;
+	}
+
+	dev_dbg(dev, "size = %lld, alloc_size = %lld, npages = %lld\n",
+		lm_file->size, lm_file->alloc_size, lm_file->npages);
+
+	pds_vfio->save_file = lm_file;
+
+	return 0;
+}
+
+static ssize_t
+pds_vfio_restore_write(struct file *filp, const char __user *buf, size_t len, loff_t *pos)
+{
+	struct pds_vfio_lm_file *lm_file = filp->private_data;
+	loff_t requested_length;
+	ssize_t done = 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(&lm_file->lock);
+
+	while (len) {
+		size_t page_offset;
+		struct page *page;
+		size_t page_len;
+		u8 *to_buff;
+		int err;
+
+		page_offset = (*pos) % PAGE_SIZE;
+		page = pds_vfio_get_file_page(lm_file, *pos - page_offset);
+		if (!page) {
+			if (done == 0)
+				done = -EINVAL;
+			goto out_unlock;
+		}
+
+		page_len = min_t(size_t, len, PAGE_SIZE - page_offset);
+		to_buff = kmap_local_page(page);
+		err = copy_from_user(to_buff + page_offset, buf, page_len);
+		kunmap_local(to_buff);
+		if (err) {
+			done = -EFAULT;
+			goto out_unlock;
+		}
+		*pos += page_len;
+		len -= page_len;
+		done += page_len;
+		buf += page_len;
+		lm_file->size += page_len;
+	}
+out_unlock:
+	mutex_unlock(&lm_file->lock);
+	return done;
+}
+
+static const struct file_operations
+pds_vfio_restore_fops = {
+	.owner = THIS_MODULE,
+	.write = pds_vfio_restore_write,
+	.release = pds_vfio_release_file,
+	.llseek = no_llseek,
+};
+
+static int
+pds_vfio_get_restore_file(struct pds_vfio_pci_device *pds_vfio)
+{
+	struct device *dev = &pds_vfio->vfio_coredev.pdev->dev;
+	struct pds_vfio_lm_file *lm_file;
+	int err = 0;
+	u64 size;
+
+	size = sizeof(union pds_lm_dev_state);
+
+	dev_dbg(dev, "restore status, size = %lld\n", size);
+
+	if (!size) {
+		err = -EIO;
+		dev_err(dev, "invalid state size");
+		goto err_get_lm_status;
+	}
+
+	lm_file = pds_vfio_get_lm_file(&pds_vfio_restore_fops,
+				       O_WRONLY, size);
+	if (!lm_file) {
+		err = -ENOENT;
+		dev_err(dev, "failed to create restore file");
+		goto err_get_lm_file;
+	}
+	pds_vfio->restore_file = lm_file;
+
+	return 0;
+
+err_get_lm_file:
+err_get_lm_status:
+	return err;
+}
+
+struct file *
+pds_vfio_step_device_state_locked(struct pds_vfio_pci_device *pds_vfio,
+				  enum vfio_device_mig_state next)
+{
+	enum vfio_device_mig_state cur = pds_vfio->state;
+	int err;
+
+	if (cur == VFIO_DEVICE_STATE_STOP && next == VFIO_DEVICE_STATE_STOP_COPY) {
+		err = pds_vfio_get_save_file(pds_vfio);
+		if (err)
+			return ERR_PTR(err);
+
+		err = pds_vfio_get_lm_state_cmd(pds_vfio);
+		if (err) {
+			pds_vfio_put_save_file(pds_vfio);
+			return ERR_PTR(err);
+		}
+
+		return pds_vfio->save_file->filep;
+	}
+
+	if (cur == VFIO_DEVICE_STATE_STOP_COPY && next == VFIO_DEVICE_STATE_STOP) {
+		pds_vfio_put_save_file(pds_vfio);
+		pds_vfio_send_host_vf_lm_status_cmd(pds_vfio,
+						    PDS_LM_STA_NONE);
+		return NULL;
+	}
+
+	if (cur == VFIO_DEVICE_STATE_STOP && next == VFIO_DEVICE_STATE_RESUMING) {
+		err = pds_vfio_get_restore_file(pds_vfio);
+		if (err)
+			return ERR_PTR(err);
+
+		return pds_vfio->restore_file->filep;
+	}
+
+	if (cur == VFIO_DEVICE_STATE_RESUMING && next == VFIO_DEVICE_STATE_STOP) {
+		err = pds_vfio_set_lm_state_cmd(pds_vfio);
+		if (err)
+			return ERR_PTR(err);
+
+		pds_vfio_put_restore_file(pds_vfio);
+		return NULL;
+	}
+
+	if (cur == VFIO_DEVICE_STATE_RUNNING && next == VFIO_DEVICE_STATE_RUNNING_P2P) {
+		pds_vfio_send_host_vf_lm_status_cmd(pds_vfio, PDS_LM_STA_IN_PROGRESS);
+		err = pds_vfio_suspend_device_cmd(pds_vfio);
+		if (err)
+			return ERR_PTR(err);
+
+		return NULL;
+	}
+
+	if (cur == VFIO_DEVICE_STATE_RUNNING_P2P && next == VFIO_DEVICE_STATE_RUNNING) {
+		err = pds_vfio_resume_device_cmd(pds_vfio);
+		if (err)
+			return ERR_PTR(err);
+
+		pds_vfio_send_host_vf_lm_status_cmd(pds_vfio,
+						    PDS_LM_STA_NONE);
+		return NULL;
+	}
+
+	if (cur == VFIO_DEVICE_STATE_STOP && next == VFIO_DEVICE_STATE_RUNNING_P2P)
+		return NULL;
+
+	if (cur == VFIO_DEVICE_STATE_RUNNING_P2P && next == VFIO_DEVICE_STATE_STOP)
+		return NULL;
+
+	return ERR_PTR(-EINVAL);
+}
diff --git a/drivers/vfio/pci/pds/lm.h b/drivers/vfio/pci/pds/lm.h
new file mode 100644
index 000000000000..72d439819994
--- /dev/null
+++ b/drivers/vfio/pci/pds/lm.h
@@ -0,0 +1,41 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright(c) 2023 Advanced Micro Devices, Inc. */
+
+#ifndef _LM_H_
+#define _LM_H_
+
+#include <linux/fs.h>
+#include <linux/mutex.h>
+#include <linux/scatterlist.h>
+#include <linux/types.h>
+
+#include <linux/pds/pds_lm.h>
+
+struct pds_vfio_lm_file {
+	struct file *filep;
+	struct mutex lock;	/* protect live migration data file */
+	u64 size;		/* Size with valid data */
+	u64 alloc_size;		/* Total allocated size. Always >= len */
+	struct page **pages;	/* Backing pages for file */
+	unsigned long long npages;
+	struct sg_table sg_table;	/* SG table for backing pages */
+	struct pds_lm_sg_elem *sgl;	/* DMA mapping */
+	dma_addr_t sgl_addr;
+	u16 num_sge;
+	struct scatterlist *last_offset_sg;	/* Iterator */
+	unsigned int sg_last_entry;
+	unsigned long last_offset;
+};
+
+struct pds_vfio_pci_device;
+
+struct file *
+pds_vfio_step_device_state_locked(struct pds_vfio_pci_device *pds_vfio,
+				  enum vfio_device_mig_state next);
+
+void
+pds_vfio_put_save_file(struct pds_vfio_pci_device *pds_vfio);
+void
+pds_vfio_put_restore_file(struct pds_vfio_pci_device *pds_vfio);
+
+#endif /* _LM_H_ */
diff --git a/drivers/vfio/pci/pds/pci_drv.c b/drivers/vfio/pci/pds/pci_drv.c
index dca7d457bd8c..91d9a66d847a 100644
--- a/drivers/vfio/pci/pds/pci_drv.c
+++ b/drivers/vfio/pci/pds/pci_drv.c
@@ -75,12 +75,27 @@  pds_vfio_pci_table[] = {
 };
 MODULE_DEVICE_TABLE(pci, pds_vfio_pci_table);
 
+static void
+pds_vfio_pci_aer_reset_done(struct pci_dev *pdev)
+{
+	struct pds_vfio_pci_device *pds_vfio = pds_vfio_pci_drvdata(pdev);
+
+	pds_vfio_reset(pds_vfio);
+}
+
+static const struct
+pci_error_handlers pds_vfio_pci_err_handlers = {
+	.reset_done = pds_vfio_pci_aer_reset_done,
+	.error_detected = vfio_pci_core_aer_err_detected,
+};
+
 static struct pci_driver
 pds_vfio_pci_driver = {
 	.name = KBUILD_MODNAME,
 	.id_table = pds_vfio_pci_table,
 	.probe = pds_vfio_pci_probe,
 	.remove = pds_vfio_pci_remove,
+	.err_handler = &pds_vfio_pci_err_handlers,
 	.driver_managed_dma = true,
 };
 
diff --git a/drivers/vfio/pci/pds/vfio_dev.c b/drivers/vfio/pci/pds/vfio_dev.c
index 228b27a0aa60..0c6e6c645f34 100644
--- a/drivers/vfio/pci/pds/vfio_dev.c
+++ b/drivers/vfio/pci/pds/vfio_dev.c
@@ -4,6 +4,7 @@ 
 #include <linux/vfio.h>
 #include <linux/vfio_pci_core.h>
 
+#include "lm.h"
 #include "vfio_dev.h"
 
 struct pci_dev *
@@ -12,6 +13,12 @@  pds_vfio_to_pci_dev(struct pds_vfio_pci_device *pds_vfio)
 	return  pds_vfio->vfio_coredev.pdev;
 }
 
+struct device *
+pds_vfio_to_dev(struct pds_vfio_pci_device *pds_vfio)
+{
+	return &pds_vfio_to_pci_dev(pds_vfio)->dev;
+}
+
 struct pds_vfio_pci_device *
 pds_vfio_pci_drvdata(struct pci_dev *pdev)
 {
@@ -21,6 +28,103 @@  pds_vfio_pci_drvdata(struct pci_dev *pdev)
 			    vfio_coredev);
 }
 
+static void
+pds_vfio_state_mutex_unlock(struct pds_vfio_pci_device *pds_vfio)
+{
+again:
+	spin_lock(&pds_vfio->reset_lock);
+	if (pds_vfio->deferred_reset) {
+		pds_vfio->deferred_reset = false;
+		if (pds_vfio->state == VFIO_DEVICE_STATE_ERROR) {
+			pds_vfio->state = VFIO_DEVICE_STATE_RUNNING;
+			pds_vfio_put_restore_file(pds_vfio);
+			pds_vfio_put_save_file(pds_vfio);
+		}
+		spin_unlock(&pds_vfio->reset_lock);
+		goto again;
+	}
+	mutex_unlock(&pds_vfio->state_mutex);
+	spin_unlock(&pds_vfio->reset_lock);
+}
+
+void
+pds_vfio_reset(struct pds_vfio_pci_device *pds_vfio)
+{
+	spin_lock(&pds_vfio->reset_lock);
+	pds_vfio->deferred_reset = true;
+	if (!mutex_trylock(&pds_vfio->state_mutex)) {
+		spin_unlock(&pds_vfio->reset_lock);
+		return;
+	}
+	spin_unlock(&pds_vfio->reset_lock);
+	pds_vfio_state_mutex_unlock(pds_vfio);
+}
+
+static struct file *
+pds_vfio_set_device_state(struct vfio_device *vdev,
+			  enum vfio_device_mig_state new_state)
+{
+	struct pds_vfio_pci_device *pds_vfio =
+		container_of(vdev, struct pds_vfio_pci_device,
+			     vfio_coredev.vdev);
+	struct file *res = NULL;
+
+	mutex_lock(&pds_vfio->state_mutex);
+	while (new_state != pds_vfio->state) {
+		enum vfio_device_mig_state next_state;
+
+		int err = vfio_mig_get_next_state(vdev, pds_vfio->state,
+						  new_state, &next_state);
+		if (err) {
+			res = ERR_PTR(err);
+			break;
+		}
+
+		res = pds_vfio_step_device_state_locked(pds_vfio, next_state);
+		if (IS_ERR(res))
+			break;
+
+		pds_vfio->state = next_state;
+
+		if (WARN_ON(res && new_state != pds_vfio->state)) {
+			res = ERR_PTR(-EINVAL);
+			break;
+		}
+	}
+	pds_vfio_state_mutex_unlock(pds_vfio);
+
+	return res;
+}
+
+static int
+pds_vfio_get_device_state(struct vfio_device *vdev,
+			  enum vfio_device_mig_state *current_state)
+{
+	struct pds_vfio_pci_device *pds_vfio =
+		container_of(vdev, struct pds_vfio_pci_device,
+			     vfio_coredev.vdev);
+
+	mutex_lock(&pds_vfio->state_mutex);
+	*current_state = pds_vfio->state;
+	pds_vfio_state_mutex_unlock(pds_vfio);
+	return 0;
+}
+
+static int
+pds_vfio_get_device_state_size(struct vfio_device *vdev,
+			       unsigned long *stop_copy_length)
+{
+	*stop_copy_length = PDS_LM_DEVICE_STATE_LENGTH;
+	return 0;
+}
+
+static const struct vfio_migration_ops
+pds_vfio_lm_ops = {
+	.migration_set_state = pds_vfio_set_device_state,
+	.migration_get_state = pds_vfio_get_device_state,
+	.migration_get_data_size = pds_vfio_get_device_state_size
+};
+
 static int
 pds_vfio_init_device(struct vfio_device *vdev)
 {
@@ -37,6 +141,9 @@  pds_vfio_init_device(struct vfio_device *vdev)
 	pds_vfio->vf_id = pci_iov_vf_id(pdev);
 	pds_vfio->pci_id = PCI_DEVID(pdev->bus->number, pdev->devfn);
 
+	vdev->migration_flags = VFIO_MIGRATION_STOP_COPY | VFIO_MIGRATION_P2P;
+	vdev->mig_ops = &pds_vfio_lm_ops;
+
 	dev_dbg(&pdev->dev, "%s: PF %#04x VF %#04x (%d) vf_id %d domain %d pds_vfio %p\n",
 		__func__, pci_dev_id(pdev->physfn),
 		pds_vfio->pci_id, pds_vfio->pci_id, pds_vfio->vf_id,
@@ -57,18 +164,36 @@  pds_vfio_open_device(struct vfio_device *vdev)
 	if (err)
 		return err;
 
+	mutex_init(&pds_vfio->state_mutex);
+	pds_vfio->state = VFIO_DEVICE_STATE_RUNNING;
+
 	vfio_pci_core_finish_enable(&pds_vfio->vfio_coredev);
 
 	return 0;
 }
 
+static void
+pds_vfio_close_device(struct vfio_device *vdev)
+{
+	struct pds_vfio_pci_device *pds_vfio =
+		container_of(vdev, struct pds_vfio_pci_device,
+			     vfio_coredev.vdev);
+
+	mutex_lock(&pds_vfio->state_mutex);
+	pds_vfio_put_restore_file(pds_vfio);
+	pds_vfio_put_save_file(pds_vfio);
+	mutex_unlock(&pds_vfio->state_mutex);
+	mutex_destroy(&pds_vfio->state_mutex);
+	vfio_pci_core_close_device(vdev);
+}
+
 static const struct vfio_device_ops
 pds_vfio_ops = {
 	.name = "pds-vfio",
 	.init = pds_vfio_init_device,
 	.release = vfio_pci_core_release_dev,
 	.open_device = pds_vfio_open_device,
-	.close_device = vfio_pci_core_close_device,
+	.close_device = pds_vfio_close_device,
 	.ioctl = vfio_pci_core_ioctl,
 	.device_feature = vfio_pci_core_ioctl_feature,
 	.read = vfio_pci_core_read,
diff --git a/drivers/vfio/pci/pds/vfio_dev.h b/drivers/vfio/pci/pds/vfio_dev.h
index 92e8ff241ca8..df6208a7140b 100644
--- a/drivers/vfio/pci/pds/vfio_dev.h
+++ b/drivers/vfio/pci/pds/vfio_dev.h
@@ -7,12 +7,21 @@ 
 #include <linux/pci.h>
 #include <linux/vfio_pci_core.h>
 
+#include "lm.h"
+
 struct pdsc;
 
 struct pds_vfio_pci_device {
 	struct vfio_pci_core_device vfio_coredev;
 	struct pdsc *pdsc;
 
+	struct pds_vfio_lm_file *save_file;
+	struct pds_vfio_lm_file *restore_file;
+	struct mutex state_mutex; /* protect migration state */
+	enum vfio_device_mig_state state;
+	spinlock_t reset_lock; /* protect reset_done flow */
+	u8 deferred_reset;
+
 	int vf_id;
 	int pci_id;
 	u16 client_id;
@@ -20,7 +29,9 @@  struct pds_vfio_pci_device {
 
 const struct vfio_device_ops *pds_vfio_ops_info(void);
 struct pds_vfio_pci_device *pds_vfio_pci_drvdata(struct pci_dev *pdev);
+void pds_vfio_reset(struct pds_vfio_pci_device *pds_vfio);
 
 struct pci_dev *pds_vfio_to_pci_dev(struct pds_vfio_pci_device *pds_vfio);
+struct device *pds_vfio_to_dev(struct pds_vfio_pci_device *pds_vfio);
 
 #endif /* _VFIO_DEV_H_ */
diff --git a/include/linux/pds/pds_adminq.h b/include/linux/pds/pds_adminq.h
index 98a60ce87b92..897b966c52ea 100644
--- a/include/linux/pds/pds_adminq.h
+++ b/include/linux/pds/pds_adminq.h
@@ -4,6 +4,8 @@ 
 #ifndef _PDS_CORE_ADMINQ_H_
 #define _PDS_CORE_ADMINQ_H_
 
+#include "pds_lm.h"
+
 #define PDSC_ADMINQ_MAX_POLL_INTERVAL	256
 
 enum pds_core_adminq_flags {
@@ -600,6 +602,14 @@  union pds_core_adminq_cmd {
 
 	struct pds_core_q_identify_cmd    q_ident;
 	struct pds_core_q_init_cmd        q_init;
+
+	struct pds_lm_suspend_cmd		lm_suspend;
+	struct pds_lm_suspend_status_cmd	lm_suspend_status;
+	struct pds_lm_resume_cmd		lm_resume;
+	struct pds_lm_status_cmd		lm_status;
+	struct pds_lm_save_cmd			lm_save;
+	struct pds_lm_restore_cmd		lm_restore;
+	struct pds_lm_host_vf_status_cmd	lm_host_vf_status;
 };
 
 union pds_core_adminq_comp {
@@ -621,6 +631,8 @@  union pds_core_adminq_comp {
 
 	struct pds_core_q_identify_comp   q_ident;
 	struct pds_core_q_init_comp       q_init;
+
+	struct pds_lm_status_comp		lm_status;
 };
 
 #ifndef __CHECKER__
diff --git a/include/linux/pds/pds_lm.h b/include/linux/pds/pds_lm.h
index 26d17efeff28..f1b0beb3c87b 100644
--- a/include/linux/pds/pds_lm.h
+++ b/include/linux/pds/pds_lm.h
@@ -7,5 +7,211 @@ 
 #include "pds_common.h"
 
 #define PDS_LM_DEV_NAME		PDS_CORE_DRV_NAME "." PDS_DEV_TYPE_LM_STR
+#define PDS_LM_DEVICE_STATE_LENGTH		65536
+#define PDS_LM_CHECK_DEVICE_STATE_LENGTH(X)					\
+			PDS_CORE_SIZE_CHECK(union, PDS_LM_DEVICE_STATE_LENGTH, X)
+
+/*
+ * enum pds_lm_cmd_opcode - Live Migration Device commands
+ */
+enum pds_lm_cmd_opcode {
+	PDS_LM_CMD_HOST_VF_STATUS  = 1,
+
+	/* Device state commands */
+	PDS_LM_CMD_STATUS          = 16,
+	PDS_LM_CMD_SUSPEND         = 18,
+	PDS_LM_CMD_SUSPEND_STATUS  = 19,
+	PDS_LM_CMD_RESUME          = 20,
+	PDS_LM_CMD_SAVE            = 21,
+	PDS_LM_CMD_RESTORE         = 22,
+};
+
+/**
+ * struct pds_lm_cmd - generic command
+ * @opcode:	Opcode
+ * @rsvd:	Word boundary padding
+ * @vf_id:	VF id
+ * @rsvd2:	Structure padding to 60 Bytes
+ */
+struct pds_lm_cmd {
+	u8     opcode;
+	u8     rsvd;
+	__le16 vf_id;
+	u8     rsvd2[56];
+};
+
+/**
+ * struct pds_lm_comp - generic command completion
+ * @status:	Status of the command (enum pds_core_status_code)
+ * @rsvd:	Structure padding to 16 Bytes
+ */
+struct pds_lm_comp {
+	u8 status;
+	u8 rsvd[15];
+};
+
+/**
+ * struct pds_lm_status_cmd - STATUS command
+ * @opcode:	Opcode
+ * @rsvd:	Word boundary padding
+ * @vf_id:	VF id
+ */
+struct pds_lm_status_cmd {
+	u8     opcode;
+	u8     rsvd;
+	__le16 vf_id;
+};
+
+/**
+ * struct pds_lm_status_comp - STATUS command completion
+ * @status:		Status of the command (enum pds_core_status_code)
+ * @rsvd:		Word boundary padding
+ * @comp_index:		Index in the desc ring for which this is the completion
+ * @size:		Size of the device state
+ * @rsvd2:		Word boundary padding
+ * @color:		Color bit
+ */
+struct pds_lm_status_comp {
+	u8     status;
+	u8     rsvd;
+	__le16 comp_index;
+	union {
+		__le64 size;
+		u8     rsvd2[11];
+	} __packed;
+	u8     color;
+};
+
+/**
+ * struct pds_lm_suspend_cmd - SUSPEND command
+ * @opcode:	Opcode PDS_LM_CMD_SUSPEND
+ * @rsvd:	Word boundary padding
+ * @vf_id:	VF id
+ */
+struct pds_lm_suspend_cmd {
+	u8     opcode;
+	u8     rsvd;
+	__le16 vf_id;
+};
+
+/**
+ * struct pds_lm_suspend_comp - SUSPEND command completion
+ * @status:		Status of the command (enum pds_core_status_code)
+ * @rsvd:		Word boundary padding
+ * @comp_index:		Index in the desc ring for which this is the completion
+ * @state_size:		Size of the device state computed post suspend
+ * @rsvd2:		Word boundary padding
+ * @color:		Color bit
+ */
+struct pds_lm_suspend_comp {
+	u8     status;
+	u8     rsvd;
+	__le16 comp_index;
+	union {
+		__le64 state_size;
+		u8     rsvd2[11];
+	} __packed;
+	u8     color;
+};
+
+/**
+ * struct pds_lm_suspend_status_cmd - SUSPEND status command
+ * @opcode:	Opcode PDS_AQ_CMD_LM_SUSPEND_STATUS
+ * @rsvd:	Word boundary padding
+ * @vf_id:	VF id
+ */
+struct pds_lm_suspend_status_cmd {
+	u8 opcode;
+	u8 rsvd;
+	__le16 vf_id;
+};
+
+/**
+ * struct pds_lm_resume_cmd - RESUME command
+ * @opcode:	Opcode PDS_LM_CMD_RESUME
+ * @rsvd:	Word boundary padding
+ * @vf_id:	VF id
+ */
+struct pds_lm_resume_cmd {
+	u8     opcode;
+	u8     rsvd;
+	__le16 vf_id;
+};
+
+/**
+ * struct pds_lm_sg_elem - Transmit scatter-gather (SG) descriptor element
+ * @addr:	DMA address of SG element data buffer
+ * @len:	Length of SG element data buffer, in bytes
+ * @rsvd:	Word boundary padding
+ */
+struct pds_lm_sg_elem {
+	__le64 addr;
+	__le32 len;
+	__le16 rsvd[2];
+};
+
+/**
+ * struct pds_lm_save_cmd - SAVE command
+ * @opcode:	Opcode PDS_LM_CMD_SAVE
+ * @rsvd:	Word boundary padding
+ * @vf_id:	VF id
+ * @rsvd2:	Word boundary padding
+ * @sgl_addr:	IOVA address of the SGL to dma the device state
+ * @num_sge:	Total number of SG elements
+ */
+struct pds_lm_save_cmd {
+	u8     opcode;
+	u8     rsvd;
+	__le16 vf_id;
+	u8     rsvd2[4];
+	__le64 sgl_addr;
+	__le32 num_sge;
+} __packed;
+
+/**
+ * struct pds_lm_restore_cmd - RESTORE command
+ * @opcode:	Opcode PDS_LM_CMD_RESTORE
+ * @rsvd:	Word boundary padding
+ * @vf_id:	VF id
+ * @rsvd2:	Word boundary padding
+ * @sgl_addr:	IOVA address of the SGL to dma the device state
+ * @num_sge:	Total number of SG elements
+ */
+struct pds_lm_restore_cmd {
+	u8     opcode;
+	u8     rsvd;
+	__le16 vf_id;
+	u8     rsvd2[4];
+	__le64 sgl_addr;
+	__le32 num_sge;
+} __packed;
+
+/**
+ * union pds_lm_dev_state - device state information
+ * @words:	Device state words
+ */
+union pds_lm_dev_state {
+	__le32 words[PDS_LM_DEVICE_STATE_LENGTH / sizeof(__le32)];
+};
+
+enum pds_lm_host_vf_status {
+	PDS_LM_STA_NONE = 0,
+	PDS_LM_STA_IN_PROGRESS,
+	PDS_LM_STA_MAX,
+};
+
+/**
+ * struct pds_lm_host_vf_status_cmd - HOST_VF_STATUS command
+ * @opcode:	Opcode PDS_LM_CMD_HOST_VF_STATUS
+ * @rsvd:	Word boundary padding
+ * @vf_id:	VF id
+ * @status:	Current LM status of host VF driver (enum pds_lm_host_status)
+ */
+struct pds_lm_host_vf_status_cmd {
+	u8     opcode;
+	u8     rsvd;
+	__le16 vf_id;
+	u8     status;
+};
 
 #endif /* _PDS_LM_H_ */