Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
Jan Beulich wrote: On 13.01.14 at 14:45, David Vrabel wrote: >> On 13/01/14 13:16, Jan Beulich wrote: >> On 13.01.14 at 14:00, Ian Campbell >wrote: On Mon, 2014-01-13 at 12:34 +, Jan Beulich wrote: On 13.01.14 at 13:01, Olaf Hering wrote: >> On Mon, Jan 13, Jan Beulich wrote: >> >>> You can't do this in one go - the first two and the last one may >be >>> set independently (and are independent in their meaning), and >>> hence need to be queried independently (xenbus_gather() fails >>> on the first absent value). >> >> Yes, thats the purpose. Since the properties are required its an >all or >> nothing thing. If they are truly optional then blkif.h should be >updated >> to say that. > > They _are_ optional. But is it true that either they are all present or they are all >absent? >>> >>> No, it's not. discard-secure is independent of the other two (but >>> those other two are tied together). >> >> Can we have a patch to blkif.h that clarifies this? >> >> e.g., >> >> feature-discard >> >>... >> >>discard-granularity and discard-offset must also be present if >>feature-discard is enabled > >It would be "may" here too afaict. But I'll defer to Konrad, who >has done more work in this area... > >Jan > >>discard-secure may also be present if feature-discard is enabled. >> >> David > > > > >___ >Xen-devel mailing list >xen-de...@lists.xen.org >http://lists.xen.org/xen-devel It is all 'may'. If there is just 'feature-discard' without any other options that is OK. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
Jan Beulich jbeul...@suse.com wrote: On 13.01.14 at 14:45, David Vrabel david.vra...@citrix.com wrote: On 13/01/14 13:16, Jan Beulich wrote: On 13.01.14 at 14:00, Ian Campbell ian.campb...@citrix.com wrote: On Mon, 2014-01-13 at 12:34 +, Jan Beulich wrote: On 13.01.14 at 13:01, Olaf Hering o...@aepfle.de wrote: On Mon, Jan 13, Jan Beulich wrote: You can't do this in one go - the first two and the last one may be set independently (and are independent in their meaning), and hence need to be queried independently (xenbus_gather() fails on the first absent value). Yes, thats the purpose. Since the properties are required its an all or nothing thing. If they are truly optional then blkif.h should be updated to say that. They _are_ optional. But is it true that either they are all present or they are all absent? No, it's not. discard-secure is independent of the other two (but those other two are tied together). Can we have a patch to blkif.h that clarifies this? e.g., feature-discard ... discard-granularity and discard-offset must also be present if feature-discard is enabled It would be may here too afaict. But I'll defer to Konrad, who has done more work in this area... Jan discard-secure may also be present if feature-discard is enabled. David ___ Xen-devel mailing list xen-de...@lists.xen.org http://lists.xen.org/xen-devel It is all 'may'. If there is just 'feature-discard' without any other options that is OK. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On 14/01/14 14:53, Olaf Hering wrote: > On Mon, Jan 13, David Vrabel wrote: > >> Can we have a patch to blkif.h that clarifies this? > > What about this change? > > diff --git a/xen/include/public/io/blkif.h b/xen/include/public/io/blkif.h > index 84eb7fd..56e2faa 100644 > --- a/xen/include/public/io/blkif.h > +++ b/xen/include/public/io/blkif.h > @@ -194,6 +194,7 @@ > * discard-secure > * Values: 0/1 (boolean) > * Default Value: 0 > + * Notes: 10 > * > * A value of "1" indicates that the backend can process > BLKIF_OP_DISCARD > * requests with the BLKIF_DISCARD_SECURE flag set. > @@ -323,9 +324,10 @@ > * For full interoperability, block front and backends should publish > * identical ring parameters, adjusted for unit differences, to the > * XenStore nodes used in both schemes. > - * (4) Devices that support discard functionality may internally allocate > - * space (discardable extents) in units that are larger than the > - * exported logical block size. > + * (4) Devices that support discard functionality may internally allocate > space > + * (discardable extents) in units that are larger than the exported > logical > + * block size. The properties discard-granularity and discard-alignment > may > + * be present if the backing device has such requirments. Clarify that both discard-granularity and discard-alignment must be present if non-sector-sized granularity is required. e.g., "If the backing device has such discardable extents the backend must provide both discard-granularity and discard-alignment." You find it useful to add these recommendations: "Backends supporting discard should include discard-granularity and discard-alignment even if it supports discarding individual sectors. Frontends should assume discard-aligment == 0 and discard-granularity == sector size if these keys are missing." > * (5) The discard-alignment parameter allows a physical device to be > * partitioned into virtual devices that do not necessarily begin or > * end on a discardable extent boundary. > @@ -344,6 +346,8 @@ > * grants that can be persistently mapped in the frontend driver, but > * due to the frontent driver implementation it should never be bigger > * than RING_SIZE * BLKIF_MAX_SEGMENTS_PER_REQUEST. > + *(10) The discard-secure property may be present and will be set to 1 if the > + * backing device supports secure discard. > */ David -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On Mon, Jan 13, David Vrabel wrote: > Can we have a patch to blkif.h that clarifies this? What about this change? diff --git a/xen/include/public/io/blkif.h b/xen/include/public/io/blkif.h index 84eb7fd..56e2faa 100644 --- a/xen/include/public/io/blkif.h +++ b/xen/include/public/io/blkif.h @@ -194,6 +194,7 @@ * discard-secure * Values: 0/1 (boolean) * Default Value: 0 + * Notes: 10 * * A value of "1" indicates that the backend can process BLKIF_OP_DISCARD * requests with the BLKIF_DISCARD_SECURE flag set. @@ -323,9 +324,10 @@ * For full interoperability, block front and backends should publish * identical ring parameters, adjusted for unit differences, to the * XenStore nodes used in both schemes. - * (4) Devices that support discard functionality may internally allocate - * space (discardable extents) in units that are larger than the - * exported logical block size. + * (4) Devices that support discard functionality may internally allocate space + * (discardable extents) in units that are larger than the exported logical + * block size. The properties discard-granularity and discard-alignment may + * be present if the backing device has such requirments. * (5) The discard-alignment parameter allows a physical device to be * partitioned into virtual devices that do not necessarily begin or * end on a discardable extent boundary. @@ -344,6 +346,8 @@ * grants that can be persistently mapped in the frontend driver, but * due to the frontent driver implementation it should never be bigger * than RING_SIZE * BLKIF_MAX_SEGMENTS_PER_REQUEST. + *(10) The discard-secure property may be present and will be set to 1 if the + * backing device supports secure discard. */ /* Olaf -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On Mon, Jan 13, David Vrabel wrote: Can we have a patch to blkif.h that clarifies this? What about this change? diff --git a/xen/include/public/io/blkif.h b/xen/include/public/io/blkif.h index 84eb7fd..56e2faa 100644 --- a/xen/include/public/io/blkif.h +++ b/xen/include/public/io/blkif.h @@ -194,6 +194,7 @@ * discard-secure * Values: 0/1 (boolean) * Default Value: 0 + * Notes: 10 * * A value of 1 indicates that the backend can process BLKIF_OP_DISCARD * requests with the BLKIF_DISCARD_SECURE flag set. @@ -323,9 +324,10 @@ * For full interoperability, block front and backends should publish * identical ring parameters, adjusted for unit differences, to the * XenStore nodes used in both schemes. - * (4) Devices that support discard functionality may internally allocate - * space (discardable extents) in units that are larger than the - * exported logical block size. + * (4) Devices that support discard functionality may internally allocate space + * (discardable extents) in units that are larger than the exported logical + * block size. The properties discard-granularity and discard-alignment may + * be present if the backing device has such requirments. * (5) The discard-alignment parameter allows a physical device to be * partitioned into virtual devices that do not necessarily begin or * end on a discardable extent boundary. @@ -344,6 +346,8 @@ * grants that can be persistently mapped in the frontend driver, but * due to the frontent driver implementation it should never be bigger * than RING_SIZE * BLKIF_MAX_SEGMENTS_PER_REQUEST. + *(10) The discard-secure property may be present and will be set to 1 if the + * backing device supports secure discard. */ /* Olaf -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On 14/01/14 14:53, Olaf Hering wrote: On Mon, Jan 13, David Vrabel wrote: Can we have a patch to blkif.h that clarifies this? What about this change? diff --git a/xen/include/public/io/blkif.h b/xen/include/public/io/blkif.h index 84eb7fd..56e2faa 100644 --- a/xen/include/public/io/blkif.h +++ b/xen/include/public/io/blkif.h @@ -194,6 +194,7 @@ * discard-secure * Values: 0/1 (boolean) * Default Value: 0 + * Notes: 10 * * A value of 1 indicates that the backend can process BLKIF_OP_DISCARD * requests with the BLKIF_DISCARD_SECURE flag set. @@ -323,9 +324,10 @@ * For full interoperability, block front and backends should publish * identical ring parameters, adjusted for unit differences, to the * XenStore nodes used in both schemes. - * (4) Devices that support discard functionality may internally allocate - * space (discardable extents) in units that are larger than the - * exported logical block size. + * (4) Devices that support discard functionality may internally allocate space + * (discardable extents) in units that are larger than the exported logical + * block size. The properties discard-granularity and discard-alignment may + * be present if the backing device has such requirments. Clarify that both discard-granularity and discard-alignment must be present if non-sector-sized granularity is required. e.g., If the backing device has such discardable extents the backend must provide both discard-granularity and discard-alignment. You find it useful to add these recommendations: Backends supporting discard should include discard-granularity and discard-alignment even if it supports discarding individual sectors. Frontends should assume discard-aligment == 0 and discard-granularity == sector size if these keys are missing. * (5) The discard-alignment parameter allows a physical device to be * partitioned into virtual devices that do not necessarily begin or * end on a discardable extent boundary. @@ -344,6 +346,8 @@ * grants that can be persistently mapped in the frontend driver, but * due to the frontent driver implementation it should never be bigger * than RING_SIZE * BLKIF_MAX_SEGMENTS_PER_REQUEST. + *(10) The discard-secure property may be present and will be set to 1 if the + * backing device supports secure discard. */ David -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
>>> On 13.01.14 at 14:45, David Vrabel wrote: > On 13/01/14 13:16, Jan Beulich wrote: > On 13.01.14 at 14:00, Ian Campbell wrote: >>> On Mon, 2014-01-13 at 12:34 +, Jan Beulich wrote: >>> On 13.01.14 at 13:01, Olaf Hering wrote: > On Mon, Jan 13, Jan Beulich wrote: > >> You can't do this in one go - the first two and the last one may be >> set independently (and are independent in their meaning), and >> hence need to be queried independently (xenbus_gather() fails >> on the first absent value). > > Yes, thats the purpose. Since the properties are required its an all or > nothing thing. If they are truly optional then blkif.h should be updated > to say that. They _are_ optional. >>> >>> But is it true that either they are all present or they are all absent? >> >> No, it's not. discard-secure is independent of the other two (but >> those other two are tied together). > > Can we have a patch to blkif.h that clarifies this? > > e.g., > > feature-discard > >... > >discard-granularity and discard-offset must also be present if >feature-discard is enabled It would be "may" here too afaict. But I'll defer to Konrad, who has done more work in this area... Jan >discard-secure may also be present if feature-discard is enabled. > > David -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On 13/01/14 13:16, Jan Beulich wrote: On 13.01.14 at 14:00, Ian Campbell wrote: >> On Mon, 2014-01-13 at 12:34 +, Jan Beulich wrote: >> On 13.01.14 at 13:01, Olaf Hering wrote: On Mon, Jan 13, Jan Beulich wrote: > You can't do this in one go - the first two and the last one may be > set independently (and are independent in their meaning), and > hence need to be queried independently (xenbus_gather() fails > on the first absent value). Yes, thats the purpose. Since the properties are required its an all or nothing thing. If they are truly optional then blkif.h should be updated to say that. >>> >>> They _are_ optional. >> >> But is it true that either they are all present or they are all absent? > > No, it's not. discard-secure is independent of the other two (but > those other two are tied together). Can we have a patch to blkif.h that clarifies this? e.g., feature-discard ... discard-granularity and discard-offset must also be present if feature-discard is enabled discard-secure may also be present if feature-discard is enabled. David -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On Mon, 2014-01-13 at 13:16 +, Jan Beulich wrote: > >>> On 13.01.14 at 14:00, Ian Campbell wrote: > > On Mon, 2014-01-13 at 12:34 +, Jan Beulich wrote: > >> >>> On 13.01.14 at 13:01, Olaf Hering wrote: > >> > On Mon, Jan 13, Jan Beulich wrote: > >> > > >> >> You can't do this in one go - the first two and the last one may be > >> >> set independently (and are independent in their meaning), and > >> >> hence need to be queried independently (xenbus_gather() fails > >> >> on the first absent value). > >> > > >> > Yes, thats the purpose. Since the properties are required its an all or > >> > nothing thing. If they are truly optional then blkif.h should be updated > >> > to say that. > >> > >> They _are_ optional. > > > > But is it true that either they are all present or they are all absent? > > No, it's not. discard-secure is independent of the other two (but > those other two are tied together). Thanks for clarifying. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
>>> On 13.01.14 at 14:00, Ian Campbell wrote: > On Mon, 2014-01-13 at 12:34 +, Jan Beulich wrote: >> >>> On 13.01.14 at 13:01, Olaf Hering wrote: >> > On Mon, Jan 13, Jan Beulich wrote: >> > >> >> You can't do this in one go - the first two and the last one may be >> >> set independently (and are independent in their meaning), and >> >> hence need to be queried independently (xenbus_gather() fails >> >> on the first absent value). >> > >> > Yes, thats the purpose. Since the properties are required its an all or >> > nothing thing. If they are truly optional then blkif.h should be updated >> > to say that. >> >> They _are_ optional. > > But is it true that either they are all present or they are all absent? No, it's not. discard-secure is independent of the other two (but those other two are tied together). Jan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On Mon, 2014-01-13 at 12:34 +, Jan Beulich wrote: > >>> On 13.01.14 at 13:01, Olaf Hering wrote: > > On Mon, Jan 13, Jan Beulich wrote: > > > >> You can't do this in one go - the first two and the last one may be > >> set independently (and are independent in their meaning), and > >> hence need to be queried independently (xenbus_gather() fails > >> on the first absent value). > > > > Yes, thats the purpose. Since the properties are required its an all or > > nothing thing. If they are truly optional then blkif.h should be updated > > to say that. > > They _are_ optional. But is it true that either they are all present or they are all absent? Ian. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On Mon, Jan 13, Jan Beulich wrote: > >>> On 13.01.14 at 13:01, Olaf Hering wrote: > > On Mon, Jan 13, Jan Beulich wrote: > > > >> You can't do this in one go - the first two and the last one may be > >> set independently (and are independent in their meaning), and > >> hence need to be queried independently (xenbus_gather() fails > >> on the first absent value). > > > > Yes, thats the purpose. Since the properties are required its an all or > > nothing thing. If they are truly optional then blkif.h should be updated > > to say that. > > They _are_ optional. In this case my first patch is correct and should be used. Olaf -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
>>> On 13.01.14 at 13:01, Olaf Hering wrote: > On Mon, Jan 13, Jan Beulich wrote: > >> You can't do this in one go - the first two and the last one may be >> set independently (and are independent in their meaning), and >> hence need to be queried independently (xenbus_gather() fails >> on the first absent value). > > Yes, thats the purpose. Since the properties are required its an all or > nothing thing. If they are truly optional then blkif.h should be updated > to say that. They _are_ optional. Jan -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On Mon, Jan 13, Jan Beulich wrote: > You can't do this in one go - the first two and the last one may be > set independently (and are independent in their meaning), and > hence need to be queried independently (xenbus_gather() fails > on the first absent value). Yes, thats the purpose. Since the properties are required its an all or nothing thing. If they are truly optional then blkif.h should be updated to say that. Olaf -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
>>> On 13.01.14 at 11:14, Olaf Hering wrote:
> --- a/drivers/block/xen-blkfront.c
> +++ b/drivers/block/xen-blkfront.c
> @@ -1634,37 +1634,22 @@ blkfront_closing(struct blkfront_info *info)
>
> static void blkfront_setup_discard(struct blkfront_info *info)
> {
> - int err;
> - char *type;
> unsigned int discard_granularity;
> unsigned int discard_alignment;
> unsigned int discard_secure;
>
> - type = xenbus_read(XBT_NIL, info->xbdev->otherend, "type", NULL);
> - if (IS_ERR(type))
> + if (xenbus_gather(XBT_NIL, info->xbdev->otherend,
> + "discard-granularity", "%u", _granularity,
> + "discard-alignment", "%u", _alignment,
> + "discard-secure", "%u", _secure,
> + NULL))
> return;
You can't do this in one go - the first two and the last one may be
set independently (and are independent in their meaning), and
hence need to be queried independently (xenbus_gather() fails
on the first absent value).
Jan
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More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On 13.01.14 at 11:14, Olaf Hering o...@aepfle.de wrote:
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -1634,37 +1634,22 @@ blkfront_closing(struct blkfront_info *info)
static void blkfront_setup_discard(struct blkfront_info *info)
{
- int err;
- char *type;
unsigned int discard_granularity;
unsigned int discard_alignment;
unsigned int discard_secure;
- type = xenbus_read(XBT_NIL, info-xbdev-otherend, type, NULL);
- if (IS_ERR(type))
+ if (xenbus_gather(XBT_NIL, info-xbdev-otherend,
+ discard-granularity, %u, discard_granularity,
+ discard-alignment, %u, discard_alignment,
+ discard-secure, %u, discard_secure,
+ NULL))
return;
You can't do this in one go - the first two and the last one may be
set independently (and are independent in their meaning), and
hence need to be queried independently (xenbus_gather() fails
on the first absent value).
Jan
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On Mon, Jan 13, Jan Beulich wrote: You can't do this in one go - the first two and the last one may be set independently (and are independent in their meaning), and hence need to be queried independently (xenbus_gather() fails on the first absent value). Yes, thats the purpose. Since the properties are required its an all or nothing thing. If they are truly optional then blkif.h should be updated to say that. Olaf -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On 13.01.14 at 13:01, Olaf Hering o...@aepfle.de wrote: On Mon, Jan 13, Jan Beulich wrote: You can't do this in one go - the first two and the last one may be set independently (and are independent in their meaning), and hence need to be queried independently (xenbus_gather() fails on the first absent value). Yes, thats the purpose. Since the properties are required its an all or nothing thing. If they are truly optional then blkif.h should be updated to say that. They _are_ optional. Jan -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On Mon, Jan 13, Jan Beulich wrote: On 13.01.14 at 13:01, Olaf Hering o...@aepfle.de wrote: On Mon, Jan 13, Jan Beulich wrote: You can't do this in one go - the first two and the last one may be set independently (and are independent in their meaning), and hence need to be queried independently (xenbus_gather() fails on the first absent value). Yes, thats the purpose. Since the properties are required its an all or nothing thing. If they are truly optional then blkif.h should be updated to say that. They _are_ optional. In this case my first patch is correct and should be used. Olaf -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On Mon, 2014-01-13 at 12:34 +, Jan Beulich wrote: On 13.01.14 at 13:01, Olaf Hering o...@aepfle.de wrote: On Mon, Jan 13, Jan Beulich wrote: You can't do this in one go - the first two and the last one may be set independently (and are independent in their meaning), and hence need to be queried independently (xenbus_gather() fails on the first absent value). Yes, thats the purpose. Since the properties are required its an all or nothing thing. If they are truly optional then blkif.h should be updated to say that. They _are_ optional. But is it true that either they are all present or they are all absent? Ian. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On 13.01.14 at 14:00, Ian Campbell ian.campb...@citrix.com wrote: On Mon, 2014-01-13 at 12:34 +, Jan Beulich wrote: On 13.01.14 at 13:01, Olaf Hering o...@aepfle.de wrote: On Mon, Jan 13, Jan Beulich wrote: You can't do this in one go - the first two and the last one may be set independently (and are independent in their meaning), and hence need to be queried independently (xenbus_gather() fails on the first absent value). Yes, thats the purpose. Since the properties are required its an all or nothing thing. If they are truly optional then blkif.h should be updated to say that. They _are_ optional. But is it true that either they are all present or they are all absent? No, it's not. discard-secure is independent of the other two (but those other two are tied together). Jan -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On Mon, 2014-01-13 at 13:16 +, Jan Beulich wrote: On 13.01.14 at 14:00, Ian Campbell ian.campb...@citrix.com wrote: On Mon, 2014-01-13 at 12:34 +, Jan Beulich wrote: On 13.01.14 at 13:01, Olaf Hering o...@aepfle.de wrote: On Mon, Jan 13, Jan Beulich wrote: You can't do this in one go - the first two and the last one may be set independently (and are independent in their meaning), and hence need to be queried independently (xenbus_gather() fails on the first absent value). Yes, thats the purpose. Since the properties are required its an all or nothing thing. If they are truly optional then blkif.h should be updated to say that. They _are_ optional. But is it true that either they are all present or they are all absent? No, it's not. discard-secure is independent of the other two (but those other two are tied together). Thanks for clarifying. -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On 13/01/14 13:16, Jan Beulich wrote: On 13.01.14 at 14:00, Ian Campbell ian.campb...@citrix.com wrote: On Mon, 2014-01-13 at 12:34 +, Jan Beulich wrote: On 13.01.14 at 13:01, Olaf Hering o...@aepfle.de wrote: On Mon, Jan 13, Jan Beulich wrote: You can't do this in one go - the first two and the last one may be set independently (and are independent in their meaning), and hence need to be queried independently (xenbus_gather() fails on the first absent value). Yes, thats the purpose. Since the properties are required its an all or nothing thing. If they are truly optional then blkif.h should be updated to say that. They _are_ optional. But is it true that either they are all present or they are all absent? No, it's not. discard-secure is independent of the other two (but those other two are tied together). Can we have a patch to blkif.h that clarifies this? e.g., feature-discard ... discard-granularity and discard-offset must also be present if feature-discard is enabled discard-secure may also be present if feature-discard is enabled. David -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [Xen-devel] [PATCH v2] xen-blkfront: remove type check from blkfront_setup_discard
On 13.01.14 at 14:45, David Vrabel david.vra...@citrix.com wrote: On 13/01/14 13:16, Jan Beulich wrote: On 13.01.14 at 14:00, Ian Campbell ian.campb...@citrix.com wrote: On Mon, 2014-01-13 at 12:34 +, Jan Beulich wrote: On 13.01.14 at 13:01, Olaf Hering o...@aepfle.de wrote: On Mon, Jan 13, Jan Beulich wrote: You can't do this in one go - the first two and the last one may be set independently (and are independent in their meaning), and hence need to be queried independently (xenbus_gather() fails on the first absent value). Yes, thats the purpose. Since the properties are required its an all or nothing thing. If they are truly optional then blkif.h should be updated to say that. They _are_ optional. But is it true that either they are all present or they are all absent? No, it's not. discard-secure is independent of the other two (but those other two are tied together). Can we have a patch to blkif.h that clarifies this? e.g., feature-discard ... discard-granularity and discard-offset must also be present if feature-discard is enabled It would be may here too afaict. But I'll defer to Konrad, who has done more work in this area... Jan discard-secure may also be present if feature-discard is enabled. David -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
