diff mbox series

[1/1] scsi: target: core: Add 8Fh VPD page

Message ID 20210729201943.40222-2-s.samoylenko@yadro.com (mailing list archive)
State New, archived
Headers show
Series scsi: target: core: Add 8Fh VPD page | expand

Commit Message

Sergey Samoylenko July 29, 2021, 8:19 p.m. UTC 
The 8Fh VPD page announces the capabilities supported by
the TCM XCOPY manager. It helps to expand the coverage of
the third-party copy manager with SCSI testing utilities.

Reviewed-by: Konstantin Shelekhin <k.shelekhin@yadro.com>
Reviewed-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
Reviewed-by: Anastasia Kovaleva <a.kovaleva@yadro.com>
Signed-off-by: Sergey Samoylenko <s.samoylenko@yadro.com>
---
 drivers/target/target_core_spc.c | 230 ++++++++++++++++++++++++++++++-
 1 file changed, 226 insertions(+), 4 deletions(-)

Comments

David Disseldorp Aug. 13, 2021, 2:52 p.m. UTC | #1 
Hi Sergey,

On Thu, 29 Jul 2021 23:19:43 +0300, Sergey Samoylenko wrote:

> The 8Fh VPD page announces the capabilities supported by
> the TCM XCOPY manager. It helps to expand the coverage of
> the third-party copy manager with SCSI testing utilities.

Please list which initiators use this VPD page, if you know of any.
Also, is there any test coverage for this? I don't see anything in
libiscsi...

> Reviewed-by: Konstantin Shelekhin <k.shelekhin@yadro.com>
> Reviewed-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
> Reviewed-by: Anastasia Kovaleva <a.kovaleva@yadro.com>
> Signed-off-by: Sergey Samoylenko <s.samoylenko@yadro.com>
> ---
>  drivers/target/target_core_spc.c | 230 ++++++++++++++++++++++++++++++-
>  1 file changed, 226 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/target/target_core_spc.c b/drivers/target/target_core_spc.c
> index 22703a0dbd07..169341712b10 100644
> --- a/drivers/target/target_core_spc.c
> +++ b/drivers/target/target_core_spc.c
...
> +/* Third-party Copy VPD page */
> +static sense_reason_t
> +spc_emulate_evpd_8f(struct se_cmd *cmd, unsigned char *buf)
> +{
> +	struct se_device *dev = cmd->se_dev;
> +	int off;
> +	u16 page_len;
> +
> +	if (!dev->dev_attrib.emulate_3pc)
> +		return TCM_INVALID_CDB_FIELD;
> +
> +	/*
> +	 * Since the Third-party copy manager in TCM is quite simple
> +	 * and supports only two commands, the function sets
> +	 * many descriptor parameters as constants.
> +	 *
> +	 * As the Copy manager supports the EXTENDED COPY(LID1) command,
> +	 * the Third-party Copy VPD page should include five mandatory
> +	 * Third-party copy descriptors. Its are:
> +	 *   0001h - Supported Commands
> +	 *   0004h - Parameter Data
> +	 *   0008h - Supported Descriptors
> +	 *   000Ch - Supported CSCD Descriptor IDs
> +	 *   8001h - General Copy Operations
> +	 *
> +	 * See spc4 section 7.8.17
> +	 */
> +
> +	off = 4;
> +
> +	/* fill descriptors */
> +	off += spc_evpd_8f_encode_supp_cmds(&buf[off]);
> +	off += spc_evpd_8f_encode_param_data(&buf[off]);
> +	off += spc_evpd_8f_encode_supp_descrs(&buf[off]);
> +	off += spc_evpd_8f_encode_supp_cscd_descr_id(&buf[off]);
> +	off += spc_evpd_8f_encode_general_copy_ops(&buf[off]);

This looks risky in terms of buf overrun. I think it'd be good to pass
a @remaining or @buf_end param to these helper functions.

Cheers, David
Roman Bolshakov Aug. 16, 2021, 6:13 p.m. UTC | #2 
On Fri, Aug 13, 2021 at 04:52:55PM +0200, David Disseldorp wrote:
> Hi Sergey,
> 
> On Thu, 29 Jul 2021 23:19:43 +0300, Sergey Samoylenko wrote:
> 
> > The 8Fh VPD page announces the capabilities supported by
> > the TCM XCOPY manager. It helps to expand the coverage of
> > the third-party copy manager with SCSI testing utilities.
> 
> Please list which initiators use this VPD page, if you know of any.
> Also, is there any test coverage for this? I don't see anything in
> libiscsi...
> 

Hi David,

ESXi is one of the hosts that inspects Third Party Copy VPD Page.
Windows detects ODX support using the page [1][2].

The page is also used by libiscsi to detect presence and features of
copy manager as was agreed with Bart in the PR [3]:

"Implementing REPORT SUPPORTED OPERATION CODES in LIO would require more
work than implementing the third-party copy VPD page.

I'm fine with relying on the third-party copy VPD page, or in other
words, to skip the copy offloading tests if that page is not supported.

There are plans to implement XCOPY support in the Linux kernel sd
driver. If nobody else volunteers I plan to work on this myself. I'm
considering to only support SCSI targets that support the third-party
copy VPD page. Or in other words, we will need support for that VPD page
anyway."

1. https://www.slideshare.net/CalvinChen5/a-joint-effort-of-the-storage-industry
2. http://sg.danny.cz/sg/ddpt_xcopy_odx.html
3. https://github.com/sahlberg/libiscsi/pull/353

> > Reviewed-by: Konstantin Shelekhin <k.shelekhin@yadro.com>
> > Reviewed-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
> > Reviewed-by: Anastasia Kovaleva <a.kovaleva@yadro.com>
> > Signed-off-by: Sergey Samoylenko <s.samoylenko@yadro.com>
> > ---
> >  drivers/target/target_core_spc.c | 230 ++++++++++++++++++++++++++++++-
> >  1 file changed, 226 insertions(+), 4 deletions(-)
> > 
> > diff --git a/drivers/target/target_core_spc.c b/drivers/target/target_core_spc.c
> > index 22703a0dbd07..169341712b10 100644
> > --- a/drivers/target/target_core_spc.c
> > +++ b/drivers/target/target_core_spc.c
> ...
> > +/* Third-party Copy VPD page */
> > +static sense_reason_t
> > +spc_emulate_evpd_8f(struct se_cmd *cmd, unsigned char *buf)
> > +{
> > +	struct se_device *dev = cmd->se_dev;
> > +	int off;
> > +	u16 page_len;
> > +
> > +	if (!dev->dev_attrib.emulate_3pc)
> > +		return TCM_INVALID_CDB_FIELD;
> > +
> > +	/*
> > +	 * Since the Third-party copy manager in TCM is quite simple
> > +	 * and supports only two commands, the function sets
> > +	 * many descriptor parameters as constants.
> > +	 *
> > +	 * As the Copy manager supports the EXTENDED COPY(LID1) command,
> > +	 * the Third-party Copy VPD page should include five mandatory
> > +	 * Third-party copy descriptors. Its are:
> > +	 *   0001h - Supported Commands
> > +	 *   0004h - Parameter Data
> > +	 *   0008h - Supported Descriptors
> > +	 *   000Ch - Supported CSCD Descriptor IDs
> > +	 *   8001h - General Copy Operations
> > +	 *
> > +	 * See spc4 section 7.8.17
> > +	 */
> > +
> > +	off = 4;
> > +
> > +	/* fill descriptors */
> > +	off += spc_evpd_8f_encode_supp_cmds(&buf[off]);
> > +	off += spc_evpd_8f_encode_param_data(&buf[off]);
> > +	off += spc_evpd_8f_encode_supp_descrs(&buf[off]);
> > +	off += spc_evpd_8f_encode_supp_cscd_descr_id(&buf[off]);
> > +	off += spc_evpd_8f_encode_general_copy_ops(&buf[off]);
> 
> This looks risky in terms of buf overrun. I think it'd be good to pass
> a @remaining or @buf_end param to these helper functions.
> 

It's doable but would require to change the signature of all existing
VPD handlers. SE_INQUIRY_BUF is hardcoded to 1kb but it's also capped by
EDTL to avoid buffer overruns:

  memcpy(rbuf, buf, min_t(u32, SE_INQUIRY_BUF, cmd->data_length));

Regards,
Roman
Sergey Samoylenko Aug. 16, 2021, 6:16 p.m. UTC | #3 
Hi David,

> Hi Sergey,
>
> On Thu, 29 Jul 2021 23:19:43 +0300, Sergey Samoylenko wrote:
>
>> The 8Fh VPD page announces the capabilities supported by
>> the TCM XCOPY manager. It helps to expand the coverage of
>> the third-party copy manager with SCSI testing utilities.
>
> Please list which initiators use this VPD page, if you know of any.
I know that the ESXi 7.0 requests the 8Fh VPD page. ESXi is one of
a few initiators who is using the XCOPY commands (vmkfstools tool).

> Also, is there any test coverage for this? I don't see anything in
> libiscsi...
After activating XCOPY in a target we got an error from
the SCSI.ReceiveCopyResults.CopyStatus test in the libiscsi.
Discussing with Bart, we decided to implement the 8Fh VPD page
for announcing TCM XCOPY features.
It is here: https://github.com/sahlberg/libiscsi/pull/353

The libiscsi has an initial version for parsing 8Fh VPD. This is used
in the SCSI.ReceiveCopyResults.CopyStatus test. It is a good idea
to add test coverage for 8Fh VPD in libiscsi. I should do this.

>
>> Reviewed-by: Konstantin Shelekhin <k.shelekhin@yadro.com>
>> Reviewed-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
>> Reviewed-by: Anastasia Kovaleva <a.kovaleva@yadro.com>
>> Signed-off-by: Sergey Samoylenko <s.samoylenko@yadro.com>
>> ---
>>  drivers/target/target_core_spc.c | 230 ++++++++++++++++++++++++++++++-
>>  1 file changed, 226 insertions(+), 4 deletions(-)
>> 
>> diff --git a/drivers/target/target_core_spc.c b/drivers/target/target_core_spc.c
>> index 22703a0dbd07..169341712b10 100644
>> --- a/drivers/target/target_core_spc.c
>> +++ b/drivers/target/target_core_spc.c
> ...
>> +/* Third-party Copy VPD page */
>> +static sense_reason_t
>> +spc_emulate_evpd_8f(struct se_cmd *cmd, unsigned char *buf)
>> +{
>> +	struct se_device *dev = cmd->se_dev;
>> +	int off;
>> +	u16 page_len;
>> +
>> +	if (!dev->dev_attrib.emulate_3pc)
>> +		return TCM_INVALID_CDB_FIELD;
>> +
>> +	/*
>> +	 * Since the Third-party copy manager in TCM is quite simple
>> +	 * and supports only two commands, the function sets
>> +	 * many descriptor parameters as constants.
>> +	 *
>> +	 * As the Copy manager supports the EXTENDED COPY(LID1) command,
>> +	 * the Third-party Copy VPD page should include five mandatory
>> +	 * Third-party copy descriptors. Its are:
>> +	 *   0001h - Supported Commands
>> +	 *   0004h - Parameter Data
>> +	 *   0008h - Supported Descriptors
>> +	 *   000Ch - Supported CSCD Descriptor IDs
>> +	 *   8001h - General Copy Operations
>> +	 *
>> +	 * See spc4 section 7.8.17
>> +	 */
>> +
>> +	off = 4;
>> +
>> +	/* fill descriptors */
>> +	off += spc_evpd_8f_encode_supp_cmds(&buf[off]);
>> +	off += spc_evpd_8f_encode_param_data(&buf[off]);
>> +	off += spc_evpd_8f_encode_supp_descrs(&buf[off]);
>> +	off += spc_evpd_8f_encode_supp_cscd_descr_id(&buf[off]);
>> +	off += spc_evpd_8f_encode_general_copy_ops(&buf[off]);
>
> This looks risky in terms of buf overrun. I think it'd be good to pass
> a @remaining or @buf_end param to these helper functions.

I thought about it, but spc_emulate_evpd_XX functions have a prototype:
	sense_reason_t	(*emulate)(struct se_cmd *, unsigned char *);
and they don't know anything about buffer length. I can use the
"SE_INQUIRY_BUF" definition, but I don't like this solution.
	
We can change the prototype of spc_emulate_evpd_XX functions, like:
	static struct {
		uint8_t page;
		sense_reason_t	(*emulate)(struct se_cmd *, unsigned char *buf, size_t len);
	} evpd_handlers[] = {
		...
	};
and return the TCM_OUT_OF_RESOURCES if we try to overrun buffer
in spc_emulate_evpd_XX. But this will require changing all "emulate_evpd" functions.

David, what do you think of this?

>
> Cheers, David

Best regards, Sergey
David Disseldorp Aug. 16, 2021, 10 p.m. UTC | #4 
On Mon, 16 Aug 2021 21:13:59 +0300, Roman Bolshakov wrote:

> On Fri, Aug 13, 2021 at 04:52:55PM +0200, David Disseldorp wrote:
> > Hi Sergey,
> > 
> > On Thu, 29 Jul 2021 23:19:43 +0300, Sergey Samoylenko wrote:
> >   
> > > The 8Fh VPD page announces the capabilities supported by
> > > the TCM XCOPY manager. It helps to expand the coverage of
> > > the third-party copy manager with SCSI testing utilities.  
> > 
> > Please list which initiators use this VPD page, if you know of any.
> > Also, is there any test coverage for this? I don't see anything in
> > libiscsi...
> >   
> 
> Hi David,
> 
> ESXi is one of the hosts that inspects Third Party Copy VPD Page.
> Windows detects ODX support using the page [1][2].

Thanks for the links. I haven't seen ESXi attempt to use it, but also
haven't checked for some time. It'd be good to get some of this
information in the commit message.

> The page is also used by libiscsi to detect presence and features of
> copy manager as was agreed with Bart in the PR [3]:

I'm probably missing something, but why wasn't the 3PC flag in the
standard inquiry page an option for this check?

> "Implementing REPORT SUPPORTED OPERATION CODES in LIO would require more
> work than implementing the third-party copy VPD page.
> 
> I'm fine with relying on the third-party copy VPD page, or in other
> words, to skip the copy offloading tests if that page is not supported.
> 
> There are plans to implement XCOPY support in the Linux kernel sd
> driver. If nobody else volunteers I plan to work on this myself. I'm
> considering to only support SCSI targets that support the third-party
> copy VPD page. Or in other words, we will need support for that VPD page
> anyway."

Okay, fair enough.

> 
> 1. https://www.slideshare.net/CalvinChen5/a-joint-effort-of-the-storage-industry
> 2. http://sg.danny.cz/sg/ddpt_xcopy_odx.html
> 3. https://github.com/sahlberg/libiscsi/pull/353
> 
> > > Reviewed-by: Konstantin Shelekhin <k.shelekhin@yadro.com>
> > > Reviewed-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
> > > Reviewed-by: Anastasia Kovaleva <a.kovaleva@yadro.com>
> > > Signed-off-by: Sergey Samoylenko <s.samoylenko@yadro.com>
> > > ---
> > >  drivers/target/target_core_spc.c | 230 ++++++++++++++++++++++++++++++-
> > >  1 file changed, 226 insertions(+), 4 deletions(-)
> > > 
> > > diff --git a/drivers/target/target_core_spc.c b/drivers/target/target_core_spc.c
> > > index 22703a0dbd07..169341712b10 100644
> > > --- a/drivers/target/target_core_spc.c
> > > +++ b/drivers/target/target_core_spc.c  
> > ...  
> > > +/* Third-party Copy VPD page */
> > > +static sense_reason_t
> > > +spc_emulate_evpd_8f(struct se_cmd *cmd, unsigned char *buf)
> > > +{
> > > +	struct se_device *dev = cmd->se_dev;
> > > +	int off;
> > > +	u16 page_len;
> > > +
> > > +	if (!dev->dev_attrib.emulate_3pc)
> > > +		return TCM_INVALID_CDB_FIELD;
> > > +
> > > +	/*
> > > +	 * Since the Third-party copy manager in TCM is quite simple
> > > +	 * and supports only two commands, the function sets
> > > +	 * many descriptor parameters as constants.
> > > +	 *
> > > +	 * As the Copy manager supports the EXTENDED COPY(LID1) command,
> > > +	 * the Third-party Copy VPD page should include five mandatory
> > > +	 * Third-party copy descriptors. Its are:
> > > +	 *   0001h - Supported Commands
> > > +	 *   0004h - Parameter Data
> > > +	 *   0008h - Supported Descriptors
> > > +	 *   000Ch - Supported CSCD Descriptor IDs
> > > +	 *   8001h - General Copy Operations
> > > +	 *
> > > +	 * See spc4 section 7.8.17
> > > +	 */
> > > +
> > > +	off = 4;
> > > +
> > > +	/* fill descriptors */
> > > +	off += spc_evpd_8f_encode_supp_cmds(&buf[off]);
> > > +	off += spc_evpd_8f_encode_param_data(&buf[off]);
> > > +	off += spc_evpd_8f_encode_supp_descrs(&buf[off]);
> > > +	off += spc_evpd_8f_encode_supp_cscd_descr_id(&buf[off]);
> > > +	off += spc_evpd_8f_encode_general_copy_ops(&buf[off]);  
> > 
> > This looks risky in terms of buf overrun. I think it'd be good to pass
> > a @remaining or @buf_end param to these helper functions.
> >   
> 
> It's doable but would require to change the signature of all existing
> VPD handlers. SE_INQUIRY_BUF is hardcoded to 1kb but it's also capped by
> EDTL to avoid buffer overruns:
> 
>   memcpy(rbuf, buf, min_t(u32, SE_INQUIRY_BUF, cmd->data_length));

That's checking the amount copied into the response buffer. My concern
is the prior writes to the staging buf.

Cheers, David
David Disseldorp Aug. 16, 2021, 10:48 p.m. UTC | #5 
On Mon, 16 Aug 2021 18:16:45 +0000, Sergey Samoylenko wrote:

> Hi David,
> 
> > Hi Sergey,
> >
> > On Thu, 29 Jul 2021 23:19:43 +0300, Sergey Samoylenko wrote:
> >  
> >> The 8Fh VPD page announces the capabilities supported by
> >> the TCM XCOPY manager. It helps to expand the coverage of
> >> the third-party copy manager with SCSI testing utilities.  
> >
> > Please list which initiators use this VPD page, if you know of any.  
> I know that the ESXi 7.0 requests the 8Fh VPD page.

Thanks. Please put this in the commit message.

> ESXi is one of
> a few initiators who is using the XCOPY commands (vmkfstools tool).
> 
> > Also, is there any test coverage for this? I don't see anything in
> > libiscsi...  
> After activating XCOPY in a target we got an error from
> the SCSI.ReceiveCopyResults.CopyStatus test in the libiscsi.
> Discussing with Bart, we decided to implement the 8Fh VPD page
> for announcing TCM XCOPY features.
> It is here: https://github.com/sahlberg/libiscsi/pull/353
> 
> The libiscsi has an initial version for parsing 8Fh VPD. This is used
> in the SCSI.ReceiveCopyResults.CopyStatus test. It is a good idea
> to add test coverage for 8Fh VPD in libiscsi. I should do this.
> 
> >  
> >> Reviewed-by: Konstantin Shelekhin <k.shelekhin@yadro.com>
> >> Reviewed-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
> >> Reviewed-by: Anastasia Kovaleva <a.kovaleva@yadro.com>
> >> Signed-off-by: Sergey Samoylenko <s.samoylenko@yadro.com>
> >> ---
> >>  drivers/target/target_core_spc.c | 230 ++++++++++++++++++++++++++++++-
> >>  1 file changed, 226 insertions(+), 4 deletions(-)
> >> 
> >> diff --git a/drivers/target/target_core_spc.c b/drivers/target/target_core_spc.c
> >> index 22703a0dbd07..169341712b10 100644
> >> --- a/drivers/target/target_core_spc.c
> >> +++ b/drivers/target/target_core_spc.c  
> > ...  
> >> +/* Third-party Copy VPD page */
> >> +static sense_reason_t
> >> +spc_emulate_evpd_8f(struct se_cmd *cmd, unsigned char *buf)
> >> +{
> >> +	struct se_device *dev = cmd->se_dev;
> >> +	int off;
> >> +	u16 page_len;
> >> +
> >> +	if (!dev->dev_attrib.emulate_3pc)
> >> +		return TCM_INVALID_CDB_FIELD;
> >> +
> >> +	/*
> >> +	 * Since the Third-party copy manager in TCM is quite simple
> >> +	 * and supports only two commands, the function sets
> >> +	 * many descriptor parameters as constants.
> >> +	 *
> >> +	 * As the Copy manager supports the EXTENDED COPY(LID1) command,
> >> +	 * the Third-party Copy VPD page should include five mandatory
> >> +	 * Third-party copy descriptors. Its are:
> >> +	 *   0001h - Supported Commands
> >> +	 *   0004h - Parameter Data
> >> +	 *   0008h - Supported Descriptors
> >> +	 *   000Ch - Supported CSCD Descriptor IDs
> >> +	 *   8001h - General Copy Operations
> >> +	 *
> >> +	 * See spc4 section 7.8.17
> >> +	 */
> >> +
> >> +	off = 4;
> >> +
> >> +	/* fill descriptors */
> >> +	off += spc_evpd_8f_encode_supp_cmds(&buf[off]);
> >> +	off += spc_evpd_8f_encode_param_data(&buf[off]);
> >> +	off += spc_evpd_8f_encode_supp_descrs(&buf[off]);
> >> +	off += spc_evpd_8f_encode_supp_cscd_descr_id(&buf[off]);
> >> +	off += spc_evpd_8f_encode_general_copy_ops(&buf[off]);  
> >
> > This looks risky in terms of buf overrun. I think it'd be good to pass
> > a @remaining or @buf_end param to these helper functions.  
> 
> I thought about it, but spc_emulate_evpd_XX functions have a prototype:
> 	sense_reason_t	(*emulate)(struct se_cmd *, unsigned char *);
> and they don't know anything about buffer length. I can use the
> "SE_INQUIRY_BUF" definition, but I don't like this solution.
> 	
> We can change the prototype of spc_emulate_evpd_XX functions, like:
> 	static struct {
> 		uint8_t page;
> 		sense_reason_t	(*emulate)(struct se_cmd *, unsigned char *buf, size_t len);
> 	} evpd_handlers[] = {
> 		...
> 	};
> and return the TCM_OUT_OF_RESOURCES if we try to overrun buffer
> in spc_emulate_evpd_XX. But this will require changing all "emulate_evpd" functions.
> 
> David, what do you think of this?

Ideally inquiry and mode sense handlers, not to mention the configfs
callbacks, would all carry explicit bounds checks. As a start I'd be
fine with buflen=SE_INQUIRY_BUF at the top of spc_emulate_evpd_8f(), but
any further steps towards doing it properly would be helpful IMO.

Cheers, David
diff mbox series

Patch

diff --git a/drivers/target/target_core_spc.c b/drivers/target/target_core_spc.c
index 22703a0dbd07..169341712b10 100644
--- a/drivers/target/target_core_spc.c
+++ b/drivers/target/target_core_spc.c
@@ -506,6 +506,217 @@  spc_emulate_evpd_86(struct se_cmd *cmd, unsigned char *buf)
 	return 0;
 }
 
+/* Third-party copy descriptor length is a multiple of four */
+static u16 __spc_evpd_8f_desc_calc_padding(u16 len)
+{
+	return (4 - (len & 3)) & 3;
+}
+
+/* Supported Commands third-party copy descriptor, spc4 7.8.17.4 */
+static int spc_evpd_8f_encode_supp_cmds(unsigned char *buf)
+{
+	u16 off = 0;
+
+	/*
+	 * TCM supports only two Third-party copy commands:
+	 *   83h/00h - EXTENDED COPY(LID1)
+	 *   84h/03h - RECEIVE COPY OPERATING PARAMETERS
+	 */
+
+	/* Set THIRD-PARTY COPY DESCRIPTOR TYPE (0001h) */
+	put_unaligned_be16(0x0001, &buf[off]);
+	off += 2;
+	/* Skip THIRD-PARTY COPY DESCRIPTOR LENGTH */
+	off += 2;
+	/* Set COMMANDS SUPPORTED LIST LENGTH for two codes */
+	buf[off++] = 6;
+	/* First command support descriptor (EXTENDED COPY(LID1)) */
+	buf[off++] = EXTENDED_COPY; /* operation code */
+	buf[off++] = 1; /* action list length */
+	buf[off++] = 0; /* service action */
+	/* Second descriptor (RECEIVE COPY OPERATING PARAMETERS) */
+	buf[off++] = RECEIVE_COPY_RESULTS;
+	buf[off++] = 1;
+	buf[off++] = RCR_SA_OPERATING_PARAMETERS;
+	/* Descriptor pad */
+	off += __spc_evpd_8f_desc_calc_padding(off);
+
+	/* Set THIRD-PARTY COPY DESCRIPTOR LENGTH */
+	put_unaligned_be16(off - 4, &buf[2]);
+
+	return off;
+}
+
+/* Parameter Data third-party copy descriptor, spc4 7.8.17.5 */
+static int spc_evpd_8f_encode_param_data(unsigned char *buf)
+{
+	u16 off = 0;
+
+	/* Set THIRD-PARTY COPY DESCRIPTOR TYPE (0004h) */
+	put_unaligned_be16(0x0004, &buf[off]);
+	off += 2;
+	/* Set THIRD-PARTY COPY DESCRIPTOR LENGTH (001Ch) */
+	put_unaligned_be16(0x001c, &buf[off]);
+	off += 2;
+	/* Skip over Reserved */
+	off += 4;
+	/* Set MAXIMUM CSCD DESCRIPTOR COUNT */
+	put_unaligned_be16(RCR_OP_MAX_TARGET_DESC_COUNT, &buf[off]);
+	off += 2;
+	/* Set MAXIMUM SEGMENT DESCRIPTOR COUNT */
+	put_unaligned_be16(RCR_OP_MAX_SG_DESC_COUNT, &buf[off]);
+	off += 2;
+	/* Set MAXIMUM DESCRIPTOR LIST LENGTH */
+	put_unaligned_be32(RCR_OP_MAX_DESC_LIST_LEN, &buf[off]);
+	off += 4;
+	/*
+	 * The MAXIMUM INLINE DATA LENGTH field should be set to ZERO
+	 * if the copy manager does not support segment descriptor
+	 * type code 04h.
+	 */
+	off += 4;
+	/* Skip over Reserved */
+	off += 12;
+
+	return off;
+}
+
+/* Supported Descriptors third-party copy descriptor, spc4 7.8.17.6 */
+static int spc_evpd_8f_encode_supp_descrs(unsigned char *buf)
+{
+	u16 off = 0;
+
+	/*
+	 * List of supported descriptor type codes:
+	 *   02h - Copy from block device to block device segment descriptor
+	 *   E4h - Identification Descriptor CSCD descriptor
+	 */
+
+	/* Set THIRD-PARTY COPY DESCRIPTOR TYPE (0008h) */
+	put_unaligned_be16(0x0008, &buf[off]);
+	off += 2;
+	/* Skip THIRD-PARTY COPY DESCRIPTOR LENGTH */
+	off += 2;
+	/* Set SUPPORTED DESCRIPTOR LIST LENGTH */
+	buf[off++] = 2;
+	/* List of supported descriptor type codes */
+	buf[off++] = 0x02;
+	buf[off++] = 0xe4;
+	/* Descriptor pad */
+	off += __spc_evpd_8f_desc_calc_padding(off);
+
+	/* Set THIRD-PARTY COPY DESCRIPTOR LENGTH */
+	put_unaligned_be16(off - 4, &buf[2]);
+
+	return off;
+}
+
+/* Supported CSCD Descriptor IDs third-party copy descriptor, spc4 7.8.17.7 */
+static int spc_evpd_8f_encode_supp_cscd_descr_id(unsigned char *buf)
+{
+	u16 off = 0;
+
+	/*
+	 * The TCM copy manager doesn't support CSCD Descriptod IDs other
+	 * than 0000h and therefore IDs List should be zero length.
+	 */
+
+	/* Set THIRD-PARTY COPY DESCRIPTOR TYPE (000Ch) */
+	put_unaligned_be16(0x000c, &buf[off]);
+	off += 2;
+	/* Skip THIRD-PARTY COPY DESCRIPTOR LENGTH */
+	off += 2;
+	/* Set SUPPORTED CSCD DESCRIPTOR IDS LIST LENGTH to ZERO */
+	off += 2;
+	/* Descriptor pad */
+	off += __spc_evpd_8f_desc_calc_padding(off);
+
+	/* Set THIRD-PARTY COPY DESCRIPTOR LENGTH */
+	put_unaligned_be16(off - 4, &buf[2]);
+
+	return off;
+}
+
+/* General Copy Operations third-party copy descriptor, spc4 7.8.17.10 */
+static int spc_evpd_8f_encode_general_copy_ops(unsigned char *buf)
+{
+	u16 off = 0;
+
+	/* Set THIRD-PARTY COPY DESCRIPTOR TYPE (8001h) */
+	put_unaligned_be16(0x8001, &buf[off]);
+	off += 2;
+	/* Set THIRD-PARTY COPY DESCRIPTOR LENGTH (0020h) */
+	put_unaligned_be16(0x0020, &buf[off]);
+	off += 2;
+	/* Set TOTAL CONCURRENT COPIES */
+	put_unaligned_be32(RCR_OP_TOTAL_CONCURR_COPIES, &buf[off]);
+	off += 4;
+	/* Set MAXIMUM IDENTIFIED CONCURRENT COPIES */
+	put_unaligned_be32(RCR_OP_MAX_CONCURR_COPIES, &buf[off]);
+	off += 4;
+	/* Set MAXIMUM SEGMENT LENGTH */
+	put_unaligned_be32(RCR_OP_MAX_SEGMENT_LEN, &buf[off]);
+	off += 4;
+	/* Set DATA SEGMENT GRANULARITY (log 2) */
+	buf[off++] = RCR_OP_DATA_SEG_GRAN_LOG2;
+	/*
+	 * Set INLINE DATA GRANULARITY (log 2) to ZERO.
+	 * TCM XCOPY manager does not support 04h (copy
+	 * inline data to stream device) descriptor type.
+	 */
+	off += 1;
+	/* Reserved */
+	off += 18;
+
+	return off;
+}
+
+/* Third-party Copy VPD page */
+static sense_reason_t
+spc_emulate_evpd_8f(struct se_cmd *cmd, unsigned char *buf)
+{
+	struct se_device *dev = cmd->se_dev;
+	int off;
+	u16 page_len;
+
+	if (!dev->dev_attrib.emulate_3pc)
+		return TCM_INVALID_CDB_FIELD;
+
+	/*
+	 * Since the Third-party copy manager in TCM is quite simple
+	 * and supports only two commands, the function sets
+	 * many descriptor parameters as constants.
+	 *
+	 * As the Copy manager supports the EXTENDED COPY(LID1) command,
+	 * the Third-party Copy VPD page should include five mandatory
+	 * Third-party copy descriptors. Its are:
+	 *   0001h - Supported Commands
+	 *   0004h - Parameter Data
+	 *   0008h - Supported Descriptors
+	 *   000Ch - Supported CSCD Descriptor IDs
+	 *   8001h - General Copy Operations
+	 *
+	 * See spc4 section 7.8.17
+	 */
+
+	off = 4;
+
+	/* fill descriptors */
+	off += spc_evpd_8f_encode_supp_cmds(&buf[off]);
+	off += spc_evpd_8f_encode_param_data(&buf[off]);
+	off += spc_evpd_8f_encode_supp_descrs(&buf[off]);
+	off += spc_evpd_8f_encode_supp_cscd_descr_id(&buf[off]);
+	off += spc_evpd_8f_encode_general_copy_ops(&buf[off]);
+
+	/*
+	 * Page Length for VPD 0x8f
+	 */
+	page_len = &buf[off] - &buf[0] - 4;
+	put_unaligned_be16(page_len, &buf[2]);
+
+	return 0;
+}
+
 /* Block Limits VPD page */
 static sense_reason_t
 spc_emulate_evpd_b0(struct se_cmd *cmd, unsigned char *buf)
@@ -702,6 +913,7 @@  static struct {
 	{ .page = 0x80, .emulate = spc_emulate_evpd_80 },
 	{ .page = 0x83, .emulate = spc_emulate_evpd_83 },
 	{ .page = 0x86, .emulate = spc_emulate_evpd_86 },
+	{ .page = 0x8f, .emulate = spc_emulate_evpd_8f },
 	{ .page = 0xb0, .emulate = spc_emulate_evpd_b0 },
 	{ .page = 0xb1, .emulate = spc_emulate_evpd_b1 },
 	{ .page = 0xb2, .emulate = spc_emulate_evpd_b2 },
@@ -712,7 +924,9 @@  static struct {
 static sense_reason_t
 spc_emulate_evpd_00(struct se_cmd *cmd, unsigned char *buf)
 {
-	int p;
+	bool emulate_3pc = cmd->se_dev->dev_attrib.emulate_3pc;
+	int i, p;
+	uint8_t page;
 
 	/*
 	 * Only report the INQUIRY EVPD=1 pages after a valid NAA
@@ -720,9 +934,17 @@  spc_emulate_evpd_00(struct se_cmd *cmd, unsigned char *buf)
 	 * during device creation/restart.
 	 */
 	if (cmd->se_dev->dev_flags & DF_EMULATED_VPD_UNIT_SERIAL) {
-		buf[3] = ARRAY_SIZE(evpd_handlers);
-		for (p = 0; p < ARRAY_SIZE(evpd_handlers); ++p)
-			buf[p + 4] = evpd_handlers[p].page;
+		for (i = 0, p = 4; i < ARRAY_SIZE(evpd_handlers); ++i) {
+			page = evpd_handlers[i].page;
+			/*
+			 * The 8Fh VPD page is announced only if the copy
+			 * manager is activated.
+			 */
+			if ((page == 0x8f) && !emulate_3pc)
+				continue;
+			buf[p++] = page;
+		}
+		buf[3] = p - 4;
 	}
 
 	return 0;