diff mbox series

[v8,vfio,4/7] vfio/pds: Add VFIO live migration support

Message ID 20230404190141.57762-5-brett.creeley@amd.com (mailing list archive)
State New, archived
Headers show
Series pds_vfio driver | expand

Commit Message

Brett Creeley April 4, 2023, 7:01 p.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     | 322 +++++++++++++++++++++
 drivers/vfio/pci/pds/cmds.h     |   8 +-
 drivers/vfio/pci/pds/lm.c       | 479 ++++++++++++++++++++++++++++++++
 drivers/vfio/pci/pds/lm.h       |  52 ++++
 drivers/vfio/pci/pds/pci_drv.c  |  16 ++
 drivers/vfio/pci/pds/vfio_dev.c | 119 +++++++-
 drivers/vfio/pci/pds/vfio_dev.h |  11 +
 include/linux/pds/pds_lm.h      | 210 +++++++++++++-
 9 files changed, 1213 insertions(+), 5 deletions(-)
 create mode 100644 drivers/vfio/pci/pds/lm.c
 create mode 100644 drivers/vfio/pci/pds/lm.h

Comments

Alex Williamson April 10, 2023, 10:05 p.m. UTC | #1
On Tue, 4 Apr 2023 12:01:38 -0700
Brett Creeley <brett.creeley@amd.com> wrote:
> diff --git a/drivers/vfio/pci/pds/lm.c b/drivers/vfio/pci/pds/lm.c
> new file mode 100644
> index 000000000000..855f5da9b99a
> --- /dev/null
> +++ b/drivers/vfio/pci/pds/lm.c
> @@ -0,0 +1,479 @@
> +// 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"
> +
> +#define PDS_VFIO_LM_FILENAME	"pds_vfio_lm"
> +
> +const char *
> +pds_vfio_lm_state(enum vfio_device_mig_state state)
> +{
> +	switch (state) {
> +	case VFIO_DEVICE_STATE_ERROR:
> +		return "VFIO_DEVICE_STATE_ERROR";
> +	case VFIO_DEVICE_STATE_STOP:
> +		return "VFIO_DEVICE_STATE_STOP";
> +	case VFIO_DEVICE_STATE_RUNNING:
> +		return "VFIO_DEVICE_STATE_RUNNING";
> +	case VFIO_DEVICE_STATE_STOP_COPY:
> +		return "VFIO_DEVICE_STATE_STOP_COPY";
> +	case VFIO_DEVICE_STATE_RESUMING:
> +		return "VFIO_DEVICE_STATE_RESUMING";
> +	case VFIO_DEVICE_STATE_RUNNING_P2P:
> +		return "VFIO_DEVICE_STATE_RUNNING_P2P";
> +	default:
> +		return "VFIO_DEVICE_STATE_INVALID";
> +	}
> +
> +	return "VFIO_DEVICE_STATE_INVALID";

Seems a tad redundant.

> +}
> +
[snip]
> +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;
> +	struct device *dev = &pds_vfio->pdev->dev;
> +	int err = 0;
> +
> +	dev_dbg(dev, "%s => %s\n",
> +		pds_vfio_lm_state(cur), pds_vfio_lm_state(next));
> +
> +	if (cur == VFIO_DEVICE_STATE_STOP && next == VFIO_DEVICE_STATE_STOP_COPY) {
> +		/* Device is already stopped
> +		 * create save device data file & get device state from firmware
> +		 */

Standard multi-line comment style please, we're not under net/ here.

> +		err = pds_vfio_get_save_file(pds_vfio);
> +		if (err)
> +			return ERR_PTR(err);
> +
> +		/* Get device state */
> +		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) {
> +		/* Device is already stopped
> +		 * delete the save device state file
> +		 */
> +		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) {
> +		/* create resume device data file */
> +		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) {
> +		/* Set device state */
> +		err = pds_vfio_set_lm_state_cmd(pds_vfio);
> +		if (err)
> +			return ERR_PTR(err);
> +
> +		/* delete resume device data file */
> +		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);
> +		/* Device should be stopped
> +		 * no interrupts, dma or change in internal state
> +		 */
> +		err = pds_vfio_suspend_device_cmd(pds_vfio);
> +		if (err)
> +			return ERR_PTR(err);
> +
> +		return NULL;
> +	}

The comment here, as well as the no-op transitions from STOP->P2P and
P2P->STOP has me concerned whether a device in this suspend state
really meets the definition of our P2P state.  The RUNNING_P2P state is
a quiescent state where the device must accept access, including
peer-to-peer DMA, but it cannot initiate DMA or interrupts.  Is that
consistent with this suspend state?  Thanks,

Alex

> +
> +	if (cur == VFIO_DEVICE_STATE_RUNNING_P2P && next == VFIO_DEVICE_STATE_RUNNING) {
> +		/* Device should be functional
> +		 * interrupts, dma, mmio or changes to internal state is allowed
> +		 */
> +		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);
> +}
Brett Creeley April 11, 2023, 5:21 p.m. UTC | #2
On 4/10/2023 3:05 PM, Alex Williamson wrote:
> Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.
> 
> 
> On Tue, 4 Apr 2023 12:01:38 -0700
> Brett Creeley <brett.creeley@amd.com> wrote:
>> diff --git a/drivers/vfio/pci/pds/lm.c b/drivers/vfio/pci/pds/lm.c
>> new file mode 100644
>> index 000000000000..855f5da9b99a
>> --- /dev/null
>> +++ b/drivers/vfio/pci/pds/lm.c
>> @@ -0,0 +1,479 @@
>> +// 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"
>> +
>> +#define PDS_VFIO_LM_FILENAME "pds_vfio_lm"
>> +
>> +const char *
>> +pds_vfio_lm_state(enum vfio_device_mig_state state)
>> +{
>> +     switch (state) {
>> +     case VFIO_DEVICE_STATE_ERROR:
>> +             return "VFIO_DEVICE_STATE_ERROR";
>> +     case VFIO_DEVICE_STATE_STOP:
>> +             return "VFIO_DEVICE_STATE_STOP";
>> +     case VFIO_DEVICE_STATE_RUNNING:
>> +             return "VFIO_DEVICE_STATE_RUNNING";
>> +     case VFIO_DEVICE_STATE_STOP_COPY:
>> +             return "VFIO_DEVICE_STATE_STOP_COPY";
>> +     case VFIO_DEVICE_STATE_RESUMING:
>> +             return "VFIO_DEVICE_STATE_RESUMING";
>> +     case VFIO_DEVICE_STATE_RUNNING_P2P:
>> +             return "VFIO_DEVICE_STATE_RUNNING_P2P";
>> +     default:
>> +             return "VFIO_DEVICE_STATE_INVALID";
>> +     }
>> +
>> +     return "VFIO_DEVICE_STATE_INVALID";
> 
> Seems a tad redundant.

I can remove this on the next revision. However, it is nice to be able 
to see the state transitions via enabling the dynamic debug statement in 
pds_vfio_step_device_state_locked(), but maybe this would make more 
sense in the layer above the device specific VFIO drivers?

> 
>> +}
>> +
> [snip]
>> +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;
>> +     struct device *dev = &pds_vfio->pdev->dev;
>> +     int err = 0;
>> +
>> +     dev_dbg(dev, "%s => %s\n",
>> +             pds_vfio_lm_state(cur), pds_vfio_lm_state(next));
>> +
>> +     if (cur == VFIO_DEVICE_STATE_STOP && next == VFIO_DEVICE_STATE_STOP_COPY) {
>> +             /* Device is already stopped
>> +              * create save device data file & get device state from firmware
>> +              */
> 
> Standard multi-line comment style please, we're not under net/ here.

Will fix. Thanks.

> 
>> +             err = pds_vfio_get_save_file(pds_vfio);
>> +             if (err)
>> +                     return ERR_PTR(err);
>> +
>> +             /* Get device state */
>> +             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) {
>> +             /* Device is already stopped
>> +              * delete the save device state file
>> +              */
>> +             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) {
>> +             /* create resume device data file */
>> +             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) {
>> +             /* Set device state */
>> +             err = pds_vfio_set_lm_state_cmd(pds_vfio);
>> +             if (err)
>> +                     return ERR_PTR(err);
>> +
>> +             /* delete resume device data file */
>> +             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);
>> +             /* Device should be stopped
>> +              * no interrupts, dma or change in internal state
>> +              */
>> +             err = pds_vfio_suspend_device_cmd(pds_vfio);
>> +             if (err)
>> +                     return ERR_PTR(err);
>> +
>> +             return NULL;
>> +     }
> 
> The comment here, as well as the no-op transitions from STOP->P2P and
> P2P->STOP has me concerned whether a device in this suspend state
> really meets the definition of our P2P state.  The RUNNING_P2P state is
> a quiescent state where the device must accept access, including
> peer-to-peer DMA, but it cannot initiate DMA or interrupts.  Is that
> consistent with this suspend state?  Thanks,
> 
> Alex

Yeah, these comments are misleading. Our device in the suspend state 
does meet the definition of the P2P and STOP states based on how you 
described them here and how they are defined in the VFIO header file.

I will remove the comments here as they are redundant since the states 
align with the documentation.

Thanks,

Brett
> 
>> +
>> +     if (cur == VFIO_DEVICE_STATE_RUNNING_P2P && next == VFIO_DEVICE_STATE_RUNNING) {
>> +             /* Device should be functional
>> +              * interrupts, dma, mmio or changes to internal state is allowed
>> +              */
>> +             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);
>> +}
> 
> --
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Jason Gunthorpe April 14, 2023, 12:52 p.m. UTC | #3
On Tue, Apr 04, 2023 at 12:01:38PM -0700, Brett Creeley wrote:
> +	union pds_core_adminq_cmd cmd = { 0 };

These should all be = {}, adding the 0 is a subtly different thing in

> +int
> +pds_vfio_suspend_device_cmd(struct pds_vfio_pci_device *pds_vfio)
> +{
> +	struct pds_lm_suspend_cmd cmd = {
> +		.opcode = PDS_LM_CMD_SUSPEND,
> +		.vf_id = cpu_to_le16(pds_vfio->vf_id),
> +	};
> +	struct pds_lm_suspend_comp comp = {0};
> +	struct pci_dev *pdev = pds_vfio->pdev;
> +	int err;
> +
> +	dev_dbg(&pdev->dev, "vf%u: Suspend device\n", pds_vfio->vf_id);
> +
> +	err = pds_client_adminq_cmd(pds_vfio,
> +				    (union pds_core_adminq_cmd *)&cmd,
> +				    sizeof(cmd),
> +				    (union pds_core_adminq_comp *)&comp,
> +				    PDS_AQ_FLAG_FASTPOLL);

These casts to a union are really weird, why isn't the union the type
on the stack?

Jason

> +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;
> +	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 = dma_alloc_coherent(dev, lm_file->num_sge *
> +				 sizeof(struct pds_lm_sg_elem),
> +				 &lm_file->sgl_addr, GFP_KERNEL);

Do you really need a coherent allocation for this?

> diff --git a/drivers/vfio/pci/pds/lm.c b/drivers/vfio/pci/pds/lm.c
> new file mode 100644
> index 000000000000..855f5da9b99a
> --- /dev/null
> +++ b/drivers/vfio/pci/pds/lm.c
> @@ -0,0 +1,479 @@
> +// 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"
> +
> +#define PDS_VFIO_LM_FILENAME	"pds_vfio_lm"

This doesn't need a define, it is typical to write the pseudo filename
in the only anon_inode_getfile()

> +static struct pds_vfio_lm_file *
> +pds_vfio_get_lm_file(const char *name, 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(name, 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;

This is the same basic thing the mlx5 driver does, you should move the
mlx5 code into some common place and just re-use it here.

> diff --git a/drivers/vfio/pci/pds/vfio_dev.h b/drivers/vfio/pci/pds/vfio_dev.h
> index 10557e8dc829..3f55861ffc7c 100644
> --- a/drivers/vfio/pci/pds/vfio_dev.h
> +++ b/drivers/vfio/pci/pds/vfio_dev.h
> @@ -7,10 +7,20 @@
>  #include <linux/pci.h>
>  #include <linux/vfio_pci_core.h>
>  
> +#include "lm.h"
> +
>  struct pds_vfio_pci_device {
>  	struct vfio_pci_core_device vfio_coredev;
>  	struct pci_dev *pdev;
>  	void *pdsc;
> +	struct device *coredev;

Why? If this is just &pdev->dev it it doesn't need to be in the struct

And pdev is just vfio_coredev->pdev, don't need to duplicate it either

Jason
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 7807dbb2c72c..bcd9f92e30b5 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_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 = { 0 };
+	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->pdev->dev, "client admin cmd failed: %pe\n",
+			 ERR_PTR(err));
+
+	return err;
+}
+
 int
 pds_vfio_register_client_cmd(struct pds_vfio_pci_device *pds_vfio)
 {
@@ -67,3 +97,295 @@  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)
+{
+	struct pds_lm_suspend_status_cmd cmd = {
+		.opcode = PDS_LM_CMD_SUSPEND_STATUS,
+		.vf_id	= cpu_to_le16(pds_vfio->vf_id),
+	};
+	struct pci_dev *pdev = pds_vfio->pdev;
+	struct pds_lm_comp comp = { 0 };
+	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_client_adminq_cmd(pds_vfio,
+					    (union pds_core_adminq_cmd *)&cmd,
+					    sizeof(cmd),
+					    (union pds_core_adminq_comp *)&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(&pdev->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(&pdev->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)
+{
+	struct pds_lm_suspend_cmd cmd = {
+		.opcode = PDS_LM_CMD_SUSPEND,
+		.vf_id = cpu_to_le16(pds_vfio->vf_id),
+	};
+	struct pds_lm_suspend_comp comp = {0};
+	struct pci_dev *pdev = pds_vfio->pdev;
+	int err;
+
+	dev_dbg(&pdev->dev, "vf%u: Suspend device\n", pds_vfio->vf_id);
+
+	err = pds_client_adminq_cmd(pds_vfio,
+				    (union pds_core_adminq_cmd *)&cmd,
+				    sizeof(cmd),
+				    (union pds_core_adminq_comp *)&comp,
+				    PDS_AQ_FLAG_FASTPOLL);
+	if (err) {
+		dev_err(&pdev->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)
+{
+	struct pds_lm_resume_cmd cmd = {
+		.opcode = PDS_LM_CMD_RESUME,
+		.vf_id = cpu_to_le16(pds_vfio->vf_id),
+	};
+	struct pds_lm_comp comp = {0};
+
+	dev_dbg(&pds_vfio->pdev->dev, "vf%u: Resume device\n", pds_vfio->vf_id);
+
+	return pds_client_adminq_cmd(pds_vfio,
+				     (union pds_core_adminq_cmd *)&cmd,
+				     sizeof(cmd),
+				     (union pds_core_adminq_comp *)&comp,
+				     0);
+}
+
+int
+pds_vfio_get_lm_status_cmd(struct pds_vfio_pci_device *pds_vfio, u64 *size)
+{
+	struct pds_lm_status_cmd cmd = {
+		.opcode = PDS_LM_CMD_STATUS,
+		.vf_id = cpu_to_le16(pds_vfio->vf_id),
+	};
+	struct pds_lm_status_comp comp = {0};
+	int err;
+
+	dev_dbg(&pds_vfio->pdev->dev, "vf%u: Get migration status\n",
+		pds_vfio->vf_id);
+
+	err = pds_client_adminq_cmd(pds_vfio,
+				    (union pds_core_adminq_cmd *)&cmd,
+				    sizeof(cmd),
+				    (union pds_core_adminq_comp *)&comp,
+				    0);
+	if (err)
+		return err;
+
+	*size = le64_to_cpu(comp.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;
+	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 = dma_alloc_coherent(dev, lm_file->num_sge *
+				 sizeof(struct pds_lm_sg_elem),
+				 &lm_file->sgl_addr, GFP_KERNEL);
+	if (!sgl) {
+		err = -ENOMEM;
+		goto err_alloc_sgl;
+	}
+
+	lm_file->sgl = sgl;
+
+	/* 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_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_free_coherent(dev, lm_file->num_sge *
+				  sizeof(struct pds_lm_sg_elem),
+				  lm_file->sgl, lm_file->sgl_addr);
+		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)
+{
+	struct pds_lm_save_cmd cmd = {
+		.opcode = PDS_LM_CMD_SAVE,
+		.vf_id = cpu_to_le16(pds_vfio->vf_id),
+	};
+	struct pci_dev *pdev = pds_vfio->pdev;
+	struct pds_vfio_lm_file *lm_file;
+	struct pds_lm_comp comp = {0};
+	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(pds_vfio->coredev, 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.sgl_addr = cpu_to_le64(lm_file->sgl_addr);
+	cmd.num_sge = cpu_to_le32(lm_file->num_sge);
+
+	err = pds_client_adminq_cmd(pds_vfio,
+				    (union pds_core_adminq_cmd *)&cmd,
+				    sizeof(cmd),
+				    (union pds_core_adminq_comp *)&comp,
+				    0);
+	if (err)
+		dev_err(&pdev->dev, "failed to get migration state: %pe\n",
+			ERR_PTR(err));
+
+	pds_vfio_dma_unmap_lm_file(pds_vfio->coredev, DMA_FROM_DEVICE, lm_file);
+
+	return err;
+}
+
+int
+pds_vfio_set_lm_state_cmd(struct pds_vfio_pci_device *pds_vfio)
+{
+	struct pds_lm_restore_cmd cmd = {
+		.opcode = PDS_LM_CMD_RESTORE,
+		.vf_id = cpu_to_le16(pds_vfio->vf_id),
+	};
+	struct pci_dev *pdev = pds_vfio->pdev;
+	struct pds_vfio_lm_file *lm_file;
+	struct pds_lm_comp comp = {0};
+	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(pds_vfio->coredev, 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.sgl_addr = cpu_to_le64(lm_file->sgl_addr);
+	cmd.num_sge = cpu_to_le32(lm_file->num_sge);
+
+	err = pds_client_adminq_cmd(pds_vfio,
+				    (union pds_core_adminq_cmd *)&cmd,
+				    sizeof(cmd),
+				    (union pds_core_adminq_comp *)&comp,
+				    0);
+	if (err)
+		dev_err(&pdev->dev, "failed to set migration state: %pe\n",
+			ERR_PTR(err));
+
+	pds_vfio_dma_unmap_lm_file(pds_vfio->coredev, 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)
+{
+	struct pds_lm_host_vf_status_cmd cmd = {
+		.opcode = PDS_LM_CMD_HOST_VF_STATUS,
+		.vf_id = cpu_to_le16(pds_vfio->vf_id),
+		.status = vf_status,
+	};
+	struct pci_dev *pdev = pds_vfio->pdev;
+	struct pds_lm_comp comp = {0};
+	int err;
+
+	dev_dbg(&pdev->dev, "vf%u: Set host VF LM status: %u",
+		pds_vfio->vf_id, cmd.status);
+	if (vf_status != PDS_LM_STA_IN_PROGRESS &&
+	    vf_status != PDS_LM_STA_NONE) {
+		dev_warn(&pdev->dev, "Invalid host VF migration status, %d\n",
+			 vf_status);
+		return;
+	}
+
+	err = pds_client_adminq_cmd(pds_vfio,
+				    (union pds_core_adminq_cmd *)&cmd,
+				    sizeof(cmd),
+				    (union pds_core_adminq_comp *)&comp,
+				    0);
+	if (err)
+		dev_warn(&pdev->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..855f5da9b99a
--- /dev/null
+++ b/drivers/vfio/pci/pds/lm.c
@@ -0,0 +1,479 @@ 
+// 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"
+
+#define PDS_VFIO_LM_FILENAME	"pds_vfio_lm"
+
+const char *
+pds_vfio_lm_state(enum vfio_device_mig_state state)
+{
+	switch (state) {
+	case VFIO_DEVICE_STATE_ERROR:
+		return "VFIO_DEVICE_STATE_ERROR";
+	case VFIO_DEVICE_STATE_STOP:
+		return "VFIO_DEVICE_STATE_STOP";
+	case VFIO_DEVICE_STATE_RUNNING:
+		return "VFIO_DEVICE_STATE_RUNNING";
+	case VFIO_DEVICE_STATE_STOP_COPY:
+		return "VFIO_DEVICE_STATE_STOP_COPY";
+	case VFIO_DEVICE_STATE_RESUMING:
+		return "VFIO_DEVICE_STATE_RESUMING";
+	case VFIO_DEVICE_STATE_RUNNING_P2P:
+		return "VFIO_DEVICE_STATE_RUNNING_P2P";
+	default:
+		return "VFIO_DEVICE_STATE_INVALID";
+	}
+
+	return "VFIO_DEVICE_STATE_INVALID";
+}
+
+static struct pds_vfio_lm_file *
+pds_vfio_get_lm_file(const char *name, 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(name, 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;
+
+	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);
+}
+
+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 pci_dev *pdev = pds_vfio->pdev;
+	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(&pdev->dev, "failed to get save status: %pe\n",
+			ERR_PTR(err));
+		return err;
+	}
+
+	dev_dbg(&pdev->dev, "save status, size = %lld\n", size);
+
+	if (!size) {
+		dev_err(&pdev->dev, "invalid state size\n");
+		return -EIO;
+	}
+
+	lm_file = pds_vfio_get_lm_file(PDS_VFIO_LM_FILENAME,
+				       &pds_vfio_save_fops,
+				       O_RDONLY, size);
+	if (!lm_file) {
+		dev_err(&pdev->dev, "failed to create save file\n");
+		return -ENOENT;
+	}
+
+	dev_dbg(&pdev->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 pci_dev *pdev = pds_vfio->pdev;
+	struct pds_vfio_lm_file *lm_file;
+	int err = 0;
+	u64 size;
+
+	size = sizeof(union pds_lm_dev_state);
+
+	dev_dbg(&pdev->dev, "restore status, size = %lld\n", size);
+
+	if (!size) {
+		err = -EIO;
+		dev_err(&pdev->dev, "invalid state size");
+		goto err_get_lm_status;
+	}
+
+	lm_file = pds_vfio_get_lm_file(PDS_VFIO_LM_FILENAME,
+				       &pds_vfio_restore_fops,
+				       O_WRONLY, size);
+	if (!lm_file) {
+		err = -ENOENT;
+		dev_err(&pdev->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;
+	struct device *dev = &pds_vfio->pdev->dev;
+	int err = 0;
+
+	dev_dbg(dev, "%s => %s\n",
+		pds_vfio_lm_state(cur), pds_vfio_lm_state(next));
+
+	if (cur == VFIO_DEVICE_STATE_STOP && next == VFIO_DEVICE_STATE_STOP_COPY) {
+		/* Device is already stopped
+		 * create save device data file & get device state from firmware
+		 */
+		err = pds_vfio_get_save_file(pds_vfio);
+		if (err)
+			return ERR_PTR(err);
+
+		/* Get device state */
+		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) {
+		/* Device is already stopped
+		 * delete the save device state file
+		 */
+		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) {
+		/* create resume device data file */
+		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) {
+		/* Set device state */
+		err = pds_vfio_set_lm_state_cmd(pds_vfio);
+		if (err)
+			return ERR_PTR(err);
+
+		/* delete resume device data file */
+		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);
+		/* Device should be stopped
+		 * no interrupts, dma or change in internal state
+		 */
+		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) {
+		/* Device should be functional
+		 * interrupts, dma, mmio or changes to internal state is allowed
+		 */
+		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..7b71ee2d1e77
--- /dev/null
+++ b/drivers/vfio/pci/pds/lm.h
@@ -0,0 +1,52 @@ 
+/* 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);
+int
+pds_vfio_dma_logging_report(struct vfio_device *vdev, unsigned long iova,
+			    unsigned long length,
+			    struct iova_bitmap *dirty);
+int
+pds_vfio_dma_logging_start(struct vfio_device *vdev,
+			   struct rb_root_cached *ranges, u32 nnodes,
+			   u64 *page_size);
+int
+pds_vfio_dma_logging_stop(struct vfio_device *vdev);
+const char *
+pds_vfio_lm_state(enum vfio_device_mig_state state);
+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 46537afdee2d..b0781d9f4246 100644
--- a/drivers/vfio/pci/pds/pci_drv.c
+++ b/drivers/vfio/pci/pds/pci_drv.c
@@ -34,6 +34,7 @@  pds_vfio_pci_probe(struct pci_dev *pdev,
 
 	dev_set_drvdata(&pdev->dev, &pds_vfio->vfio_coredev);
 	pds_vfio->pdev = pdev;
+	pds_vfio->coredev = &pdev->dev;
 	pds_vfio->pdsc = pdsc_get_pf_struct(pdev);
 
 	err = pds_vfio_register_client_cmd(pds_vfio);
@@ -72,12 +73,27 @@  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 = PDS_VFIO_DRV_NAME,
 	.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 056715dea512..e6d431347c26 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 pds_vfio_pci_device *
@@ -15,6 +16,103 @@  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)
 {
@@ -31,6 +129,9 @@  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,
@@ -51,18 +152,34 @@  pds_vfio_open_device(struct vfio_device *vdev)
 	if (err)
 		return err;
 
+	mutex_init(&pds_vfio->state_mutex);
+	dev_dbg(&pds_vfio->pdev->dev, "%s: %s => VFIO_DEVICE_STATE_RUNNING\n",
+		__func__, pds_vfio_lm_state(pds_vfio->state));
+	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_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 10557e8dc829..3f55861ffc7c 100644
--- a/drivers/vfio/pci/pds/vfio_dev.h
+++ b/drivers/vfio/pci/pds/vfio_dev.h
@@ -7,10 +7,20 @@ 
 #include <linux/pci.h>
 #include <linux/vfio_pci_core.h>
 
+#include "lm.h"
+
 struct pds_vfio_pci_device {
 	struct vfio_pci_core_device vfio_coredev;
 	struct pci_dev *pdev;
 	void *pdsc;
+	struct device *coredev;
+
+	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;
@@ -19,5 +29,6 @@  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);
 
 #endif /* _VFIO_DEV_H_ */
diff --git a/include/linux/pds/pds_lm.h b/include/linux/pds/pds_lm.h
index 2bc2bf79426e..06c1c1bd6c66 100644
--- a/include/linux/pds/pds_lm.h
+++ b/include/linux/pds/pds_lm.h
@@ -1,12 +1,216 @@ 
 /* SPDX-License-Identifier: GPL-2.0 */
-/* Copyright(c) 2022 Pensando Systems, Inc */
+/* Copyright(c) 2023 Advanced Micro Devices, Inc */
 
 #ifndef _PDS_LM_H_
 #define _PDS_LM_H_
 
-#include "pds_common.h"
-
 #define PDS_DEV_TYPE_LM_STR	"LM"
 #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_ */