| Message ID | 20191113172249.32412-1-arnaud.pouliquen@st.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2] rpmsg: core: add API to get MTU | expand |
Hi Bjorn, Suman, Gentleman reminder :) Thank in advance, Arnaud On 11/13/19 6:22 PM, Arnaud Pouliquen wrote: > Return the rpmsg buffer MTU for sending message, so rpmsg users > can split a long message in several sub rpmsg buffers. > > Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com> > --- > V1 to V2 > > V1 patch:https://lore.kernel.org/patchwork/patch/1124684/ > - Change patch title, > - as not solution today to support MTU on GLINK make ops optional, > RPMsg client API returns -ENOTSUPP in this case, > - suppress smd and glink patches. > --- > drivers/rpmsg/rpmsg_core.c | 21 +++++++++++++++++++++ > drivers/rpmsg/rpmsg_internal.h | 2 ++ > drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++ > include/linux/rpmsg.h | 10 ++++++++++ > 4 files changed, 43 insertions(+) > > diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c > index e330ec4dfc33..a6ef54c4779a 100644 > --- a/drivers/rpmsg/rpmsg_core.c > +++ b/drivers/rpmsg/rpmsg_core.c > @@ -283,6 +283,27 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, > } > EXPORT_SYMBOL(rpmsg_trysend_offchannel); > > +/** > + * rpmsg_get_mtu() - get maximum transmission buffer size for sending message. > + * @ept: the rpmsg endpoint > + * > + * This function returns maximum buffer size available for a single message. > + * > + * Return: the maximum transmission size on success and an appropriate error > + * value on failure. > + */ > + > +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept) > +{ > + if (WARN_ON(!ept)) > + return -EINVAL; > + if (!ept->ops->get_mtu) > + return -ENOTSUPP; > + > + return ept->ops->get_mtu(ept); > +} > +EXPORT_SYMBOL(rpmsg_get_mtu); > + > /* > * match an rpmsg channel with a channel info struct. > * this is used to make sure we're not creating rpmsg devices for channels > diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h > index 3fc83cd50e98..0e56e046f5c6 100644 > --- a/drivers/rpmsg/rpmsg_internal.h > +++ b/drivers/rpmsg/rpmsg_internal.h > @@ -47,6 +47,7 @@ struct rpmsg_device_ops { > * @trysendto: see @rpmsg_trysendto(), optional > * @trysend_offchannel: see @rpmsg_trysend_offchannel(), optional > * @poll: see @rpmsg_poll(), optional > + * @get_mtu: see @get_mpu(), optional > * > * Indirection table for the operations that a rpmsg backend should implement. > * In addition to @destroy_ept, the backend must at least implement @send and > @@ -66,6 +67,7 @@ struct rpmsg_endpoint_ops { > void *data, int len); > __poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp, > poll_table *wait); > + ssize_t (*get_mtu)(struct rpmsg_endpoint *ept); > }; > > int rpmsg_register_device(struct rpmsg_device *rpdev); > diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c > index 376ebbf880d6..6e48fdf24555 100644 > --- a/drivers/rpmsg/virtio_rpmsg_bus.c > +++ b/drivers/rpmsg/virtio_rpmsg_bus.c > @@ -175,6 +175,7 @@ static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data, > int len, u32 dst); > static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, > u32 dst, void *data, int len); > +static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept); > > static const struct rpmsg_endpoint_ops virtio_endpoint_ops = { > .destroy_ept = virtio_rpmsg_destroy_ept, > @@ -184,6 +185,7 @@ static const struct rpmsg_endpoint_ops virtio_endpoint_ops = { > .trysend = virtio_rpmsg_trysend, > .trysendto = virtio_rpmsg_trysendto, > .trysend_offchannel = virtio_rpmsg_trysend_offchannel, > + .get_mtu = virtio_rpmsg_get_mtu, > }; > > /** > @@ -699,6 +701,14 @@ static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, > return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); > } > > +static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept) > +{ > + struct rpmsg_device *rpdev = ept->rpdev; > + struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); > + > + return vch->vrp->buf_size - sizeof(struct rpmsg_hdr); > +} > + > static int rpmsg_recv_single(struct virtproc_info *vrp, struct device *dev, > struct rpmsg_hdr *msg, unsigned int len) > { > diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h > index 9fe156d1c018..88d7892ca93d 100644 > --- a/include/linux/rpmsg.h > +++ b/include/linux/rpmsg.h > @@ -135,6 +135,8 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, > __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp, > poll_table *wait); > > +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept); > + > #else > > static inline int register_rpmsg_device(struct rpmsg_device *dev) > @@ -242,6 +244,14 @@ static inline __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, > return 0; > } > > +static inline ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept) > +{ > + /* This shouldn't be possible */ > + WARN_ON(1); > + > + return -ENXIO; > +} > + > #endif /* IS_ENABLED(CONFIG_RPMSG) */ > > /* use a macro to avoid include chaining to get THIS_MODULE */ >
On Wed 13 Nov 09:22 PST 2019, Arnaud Pouliquen wrote: > Return the rpmsg buffer MTU for sending message, so rpmsg users > can split a long message in several sub rpmsg buffers. > I won't merge this new api without a client, and I'm still concerned about the details. > Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com> > --- > V1 to V2 > > V1 patch:https://lore.kernel.org/patchwork/patch/1124684/ > - Change patch title, > - as not solution today to support MTU on GLINK make ops optional, > RPMsg client API returns -ENOTSUPP in this case, > - suppress smd and glink patches. That's ok. > --- > drivers/rpmsg/rpmsg_core.c | 21 +++++++++++++++++++++ > drivers/rpmsg/rpmsg_internal.h | 2 ++ > drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++ > include/linux/rpmsg.h | 10 ++++++++++ > 4 files changed, 43 insertions(+) > > diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c > index e330ec4dfc33..a6ef54c4779a 100644 > --- a/drivers/rpmsg/rpmsg_core.c > +++ b/drivers/rpmsg/rpmsg_core.c > @@ -283,6 +283,27 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, > } > EXPORT_SYMBOL(rpmsg_trysend_offchannel); > > +/** > + * rpmsg_get_mtu() - get maximum transmission buffer size for sending message. > + * @ept: the rpmsg endpoint > + * > + * This function returns maximum buffer size available for a single message. > + * > + * Return: the maximum transmission size on success and an appropriate error > + * value on failure. Is the expectation that a call to rpmsg_send() with this size will eventually succeed? > + */ [..] > +static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept) > +{ > + struct rpmsg_device *rpdev = ept->rpdev; > + struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); > + > + return vch->vrp->buf_size - sizeof(struct rpmsg_hdr); I'm still under the impression that the rpmsg protocol doesn't have to operate on fixed size messages. Would this then return vrp->num_bufs * vrp->buf_size / 2 - sizeof(rpmsg_hdr)? > +} > + Regards, Bjorn
Hi Bjorn On 1/13/20 6:24 PM, Bjorn Andersson wrote: > On Wed 13 Nov 09:22 PST 2019, Arnaud Pouliquen wrote: > >> Return the rpmsg buffer MTU for sending message, so rpmsg users >> can split a long message in several sub rpmsg buffers. >> > > I won't merge this new api without a client, and I'm still concerned > about the details. The client exists: it is the rpmsg tty that i 've been rying to upstream since for a while. https://patchwork.kernel.org/cover/11130213/ This patch is the result of some comments you did on rpmsg tty thread. Suman was also interested in and request to merge it independently (https://lkml.org/lkml/2019/9/3/774). That's why i'm trying to do it in 2 steps. > >> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com> >> --- >> V1 to V2 >> >> V1 patch:https://lore.kernel.org/patchwork/patch/1124684/ >> - Change patch title, >> - as not solution today to support MTU on GLINK make ops optional, >> RPMsg client API returns -ENOTSUPP in this case, >> - suppress smd and glink patches. > > That's ok. > >> --- >> drivers/rpmsg/rpmsg_core.c | 21 +++++++++++++++++++++ >> drivers/rpmsg/rpmsg_internal.h | 2 ++ >> drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++ >> include/linux/rpmsg.h | 10 ++++++++++ >> 4 files changed, 43 insertions(+) >> >> diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c >> index e330ec4dfc33..a6ef54c4779a 100644 >> --- a/drivers/rpmsg/rpmsg_core.c >> +++ b/drivers/rpmsg/rpmsg_core.c >> @@ -283,6 +283,27 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, >> } >> EXPORT_SYMBOL(rpmsg_trysend_offchannel); >> >> +/** >> + * rpmsg_get_mtu() - get maximum transmission buffer size for sending message. >> + * @ept: the rpmsg endpoint >> + * >> + * This function returns maximum buffer size available for a single message. >> + * >> + * Return: the maximum transmission size on success and an appropriate error >> + * value on failure. > > Is the expectation that a call to rpmsg_send() with this size will > eventually succeed? yes, this should be the role of the transport layer (e.g. RPMsg VirtIO bus) to ensure this. > >> + */ > [..] >> +static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept) >> +{ >> + struct rpmsg_device *rpdev = ept->rpdev; >> + struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); >> + >> + return vch->vrp->buf_size - sizeof(struct rpmsg_hdr); > > I'm still under the impression that the rpmsg protocol doesn't have to > operate on fixed size messages. Would this then return vrp->num_bufs * > vrp->buf_size / 2 - sizeof(rpmsg_hdr)? it depends on the transport layer. For RPMsg over virtio, this is the size of the payload of a buffer so vrp->buf_size - sizeof(rpmsg_hdr) Regards, Arnaud > >> +} >> + > > Regards, > Bjorn >
Hi Arnaud, On 1/13/20 7:19 AM, Arnaud POULIQUEN wrote: > Hi Bjorn, Suman, > > Gentleman reminder :) Thanks for the revised version, and very sorry about the delay. Only one minor nit that you missed from my comments the v6 rpmsg-tty series [1], otherwise I am good with the changes. See below. FWIW, I have already been using this patch on our downstream 2020 LTS based kernel and eliminate the the need to expose the virtio_rpmsg's rpmsg_hdr to rpmsg client drivers :). > > Thank in advance, > > Arnaud > > On 11/13/19 6:22 PM, Arnaud Pouliquen wrote: >> Return the rpmsg buffer MTU for sending message, so rpmsg users >> can split a long message in several sub rpmsg buffers. >> >> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com> >> --- >> V1 to V2 >> >> V1 patch:https://lore.kernel.org/patchwork/patch/1124684/ >> - Change patch title, >> - as not solution today to support MTU on GLINK make ops optional, >> RPMsg client API returns -ENOTSUPP in this case, >> - suppress smd and glink patches. >> --- >> drivers/rpmsg/rpmsg_core.c | 21 +++++++++++++++++++++ >> drivers/rpmsg/rpmsg_internal.h | 2 ++ >> drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++ >> include/linux/rpmsg.h | 10 ++++++++++ >> 4 files changed, 43 insertions(+) >> >> diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c >> index e330ec4dfc33..a6ef54c4779a 100644 >> --- a/drivers/rpmsg/rpmsg_core.c >> +++ b/drivers/rpmsg/rpmsg_core.c >> @@ -283,6 +283,27 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, >> } >> EXPORT_SYMBOL(rpmsg_trysend_offchannel); >> >> +/** >> + * rpmsg_get_mtu() - get maximum transmission buffer size for sending message. >> + * @ept: the rpmsg endpoint >> + * >> + * This function returns maximum buffer size available for a single message. >> + * >> + * Return: the maximum transmission size on success and an appropriate error >> + * value on failure. >> + */ >> + >> +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept) >> +{ >> + if (WARN_ON(!ept)) >> + return -EINVAL; >> + if (!ept->ops->get_mtu) >> + return -ENOTSUPP; >> + >> + return ept->ops->get_mtu(ept); >> +} >> +EXPORT_SYMBOL(rpmsg_get_mtu); >> + >> /* >> * match an rpmsg channel with a channel info struct. >> * this is used to make sure we're not creating rpmsg devices for channels >> diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h >> index 3fc83cd50e98..0e56e046f5c6 100644 >> --- a/drivers/rpmsg/rpmsg_internal.h >> +++ b/drivers/rpmsg/rpmsg_internal.h >> @@ -47,6 +47,7 @@ struct rpmsg_device_ops { >> * @trysendto: see @rpmsg_trysendto(), optional >> * @trysend_offchannel: see @rpmsg_trysend_offchannel(), optional >> * @poll: see @rpmsg_poll(), optional >> + * @get_mtu: see @get_mpu(), optional In the description for the ops, 'mpu' is a typo. My earlier comment was essentially, %s/see @get_mpu()/see @rpmsg_get_mtu()/ regards Suman [1] https://patchwork.kernel.org/patch/11130209/ >> * >> * Indirection table for the operations that a rpmsg backend should implement. >> * In addition to @destroy_ept, the backend must at least implement @send and >> @@ -66,6 +67,7 @@ struct rpmsg_endpoint_ops { >> void *data, int len); >> __poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp, >> poll_table *wait); >> + ssize_t (*get_mtu)(struct rpmsg_endpoint *ept); >> }; >> >> int rpmsg_register_device(struct rpmsg_device *rpdev); >> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c >> index 376ebbf880d6..6e48fdf24555 100644 >> --- a/drivers/rpmsg/virtio_rpmsg_bus.c >> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c >> @@ -175,6 +175,7 @@ static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data, >> int len, u32 dst); >> static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, >> u32 dst, void *data, int len); >> +static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept); >> >> static const struct rpmsg_endpoint_ops virtio_endpoint_ops = { >> .destroy_ept = virtio_rpmsg_destroy_ept, >> @@ -184,6 +185,7 @@ static const struct rpmsg_endpoint_ops virtio_endpoint_ops = { >> .trysend = virtio_rpmsg_trysend, >> .trysendto = virtio_rpmsg_trysendto, >> .trysend_offchannel = virtio_rpmsg_trysend_offchannel, >> + .get_mtu = virtio_rpmsg_get_mtu, >> }; >> >> /** >> @@ -699,6 +701,14 @@ static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, >> return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); >> } >> >> +static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept) >> +{ >> + struct rpmsg_device *rpdev = ept->rpdev; >> + struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); >> + >> + return vch->vrp->buf_size - sizeof(struct rpmsg_hdr); >> +} >> + >> static int rpmsg_recv_single(struct virtproc_info *vrp, struct device *dev, >> struct rpmsg_hdr *msg, unsigned int len) >> { >> diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h >> index 9fe156d1c018..88d7892ca93d 100644 >> --- a/include/linux/rpmsg.h >> +++ b/include/linux/rpmsg.h >> @@ -135,6 +135,8 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, >> __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp, >> poll_table *wait); >> >> +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept); >> + >> #else >> >> static inline int register_rpmsg_device(struct rpmsg_device *dev) >> @@ -242,6 +244,14 @@ static inline __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, >> return 0; >> } >> >> +static inline ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept) >> +{ >> + /* This shouldn't be possible */ >> + WARN_ON(1); >> + >> + return -ENXIO; >> +} >> + >> #endif /* IS_ENABLED(CONFIG_RPMSG) */ >> >> /* use a macro to avoid include chaining to get THIS_MODULE */ >>
On 1/14/20 3:06 AM, Arnaud POULIQUEN wrote: > Hi Bjorn > > On 1/13/20 6:24 PM, Bjorn Andersson wrote: >> On Wed 13 Nov 09:22 PST 2019, Arnaud Pouliquen wrote: >> >>> Return the rpmsg buffer MTU for sending message, so rpmsg users >>> can split a long message in several sub rpmsg buffers. >>> >> >> I won't merge this new api without a client, and I'm still concerned >> about the details. > The client exists: it is the rpmsg tty that i 've been rying to upstream since for a while. > https://patchwork.kernel.org/cover/11130213/ > This patch is the result of some comments you did on rpmsg tty thread. > Suman was also interested in and request to merge it independently > (https://lkml.org/lkml/2019/9/3/774). > That's why i'm trying to do it in 2 steps. > >> >>> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com> >>> --- >>> V1 to V2 >>> >>> V1 patch:https://lore.kernel.org/patchwork/patch/1124684/ >>> - Change patch title, >>> - as not solution today to support MTU on GLINK make ops optional, >>> RPMsg client API returns -ENOTSUPP in this case, >>> - suppress smd and glink patches. >> >> That's ok. >> >>> --- >>> drivers/rpmsg/rpmsg_core.c | 21 +++++++++++++++++++++ >>> drivers/rpmsg/rpmsg_internal.h | 2 ++ >>> drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++ >>> include/linux/rpmsg.h | 10 ++++++++++ >>> 4 files changed, 43 insertions(+) >>> >>> diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c >>> index e330ec4dfc33..a6ef54c4779a 100644 >>> --- a/drivers/rpmsg/rpmsg_core.c >>> +++ b/drivers/rpmsg/rpmsg_core.c >>> @@ -283,6 +283,27 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, >>> } >>> EXPORT_SYMBOL(rpmsg_trysend_offchannel); >>> >>> +/** >>> + * rpmsg_get_mtu() - get maximum transmission buffer size for sending message. >>> + * @ept: the rpmsg endpoint >>> + * >>> + * This function returns maximum buffer size available for a single message. >>> + * >>> + * Return: the maximum transmission size on success and an appropriate error >>> + * value on failure. >> >> Is the expectation that a call to rpmsg_send() with this size will >> eventually succeed? > yes, this should be the role of the transport layer > (e.g. RPMsg VirtIO bus) to ensure this. > >> >>> + */ >> [..] >>> +static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept) >>> +{ >>> + struct rpmsg_device *rpdev = ept->rpdev; >>> + struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); >>> + >>> + return vch->vrp->buf_size - sizeof(struct rpmsg_hdr); >> >> I'm still under the impression that the rpmsg protocol doesn't have to >> operate on fixed size messages. Would this then return vrp->num_bufs * >> vrp->buf_size / 2 - sizeof(rpmsg_hdr)? There was some discussion in the past to remove the 512 bytes hard-coding and replace it with a configurable value, but that is not yet done. There was some code restructuring towards the same, but it it still fixed atm in virtio_rpmsg transport. > it depends on the transport layer. For RPMsg over virtio, this is the size > of the payload of a buffer so vrp->buf_size - sizeof(rpmsg_hdr) The vrp->num_bufs is the number of buffers available in the vring transport, vrp->buf_size is the size for each transport buffer, and every message includes the rpmsg_hdr structure, so the amount available for rpmsg clients is less by that much. regards Suman
Hi Suman, On 1/15/20 12:40 AM, Suman Anna wrote: > Hi Arnaud, > > On 1/13/20 7:19 AM, Arnaud POULIQUEN wrote: >> Hi Bjorn, Suman, >> >> Gentleman reminder :) > > Thanks for the revised version, and very sorry about the delay. Only > one minor nit that you missed from my comments the v6 rpmsg-tty series > [1], otherwise I am good with the changes. See below. > > FWIW, I have already been using this patch on our downstream 2020 LTS > based kernel and eliminate the the need to expose the virtio_rpmsg's > rpmsg_hdr to rpmsg client drivers :). Right without this API the client needs also to know the RPMSG buffer size to compute the MTU. > >> >> Thank in advance, >> >> Arnaud >> >> On 11/13/19 6:22 PM, Arnaud Pouliquen wrote: >>> Return the rpmsg buffer MTU for sending message, so rpmsg users >>> can split a long message in several sub rpmsg buffers. >>> >>> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com> >>> --- >>> V1 to V2 >>> >>> V1 patch:https://lore.kernel.org/patchwork/patch/1124684/ >>> - Change patch title, >>> - as not solution today to support MTU on GLINK make ops optional, >>> RPMsg client API returns -ENOTSUPP in this case, >>> - suppress smd and glink patches. >>> --- >>> drivers/rpmsg/rpmsg_core.c | 21 +++++++++++++++++++++ >>> drivers/rpmsg/rpmsg_internal.h | 2 ++ >>> drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++ >>> include/linux/rpmsg.h | 10 ++++++++++ >>> 4 files changed, 43 insertions(+) >>> >>> diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c >>> index e330ec4dfc33..a6ef54c4779a 100644 >>> --- a/drivers/rpmsg/rpmsg_core.c >>> +++ b/drivers/rpmsg/rpmsg_core.c >>> @@ -283,6 +283,27 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, >>> } >>> EXPORT_SYMBOL(rpmsg_trysend_offchannel); >>> >>> +/** >>> + * rpmsg_get_mtu() - get maximum transmission buffer size for sending message. >>> + * @ept: the rpmsg endpoint >>> + * >>> + * This function returns maximum buffer size available for a single message. >>> + * >>> + * Return: the maximum transmission size on success and an appropriate error >>> + * value on failure. >>> + */ >>> + >>> +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept) >>> +{ >>> + if (WARN_ON(!ept)) >>> + return -EINVAL; >>> + if (!ept->ops->get_mtu) >>> + return -ENOTSUPP; >>> + >>> + return ept->ops->get_mtu(ept); >>> +} >>> +EXPORT_SYMBOL(rpmsg_get_mtu); >>> + >>> /* >>> * match an rpmsg channel with a channel info struct. >>> * this is used to make sure we're not creating rpmsg devices for channels >>> diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h >>> index 3fc83cd50e98..0e56e046f5c6 100644 >>> --- a/drivers/rpmsg/rpmsg_internal.h >>> +++ b/drivers/rpmsg/rpmsg_internal.h >>> @@ -47,6 +47,7 @@ struct rpmsg_device_ops { >>> * @trysendto: see @rpmsg_trysendto(), optional >>> * @trysend_offchannel: see @rpmsg_trysend_offchannel(), optional >>> * @poll: see @rpmsg_poll(), optional >>> + * @get_mtu: see @get_mpu(), optional > > In the description for the ops, 'mpu' is a typo. My earlier comment was > essentially, > %s/see @get_mpu()/see @rpmsg_get_mtu()/ Sorry, completly missed it i sent a v3 Thanks, Arnaud > > regards > Suman > > [1] https://patchwork.kernel.org/patch/11130209/ > >>> * >>> * Indirection table for the operations that a rpmsg backend should implement. >>> * In addition to @destroy_ept, the backend must at least implement @send and >>> @@ -66,6 +67,7 @@ struct rpmsg_endpoint_ops { >>> void *data, int len); >>> __poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp, >>> poll_table *wait); >>> + ssize_t (*get_mtu)(struct rpmsg_endpoint *ept); >>> }; >>> >>> int rpmsg_register_device(struct rpmsg_device *rpdev); >>> diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c >>> index 376ebbf880d6..6e48fdf24555 100644 >>> --- a/drivers/rpmsg/virtio_rpmsg_bus.c >>> +++ b/drivers/rpmsg/virtio_rpmsg_bus.c >>> @@ -175,6 +175,7 @@ static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data, >>> int len, u32 dst); >>> static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, >>> u32 dst, void *data, int len); >>> +static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept); >>> >>> static const struct rpmsg_endpoint_ops virtio_endpoint_ops = { >>> .destroy_ept = virtio_rpmsg_destroy_ept, >>> @@ -184,6 +185,7 @@ static const struct rpmsg_endpoint_ops virtio_endpoint_ops = { >>> .trysend = virtio_rpmsg_trysend, >>> .trysendto = virtio_rpmsg_trysendto, >>> .trysend_offchannel = virtio_rpmsg_trysend_offchannel, >>> + .get_mtu = virtio_rpmsg_get_mtu, >>> }; >>> >>> /** >>> @@ -699,6 +701,14 @@ static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, >>> return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); >>> } >>> >>> +static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept) >>> +{ >>> + struct rpmsg_device *rpdev = ept->rpdev; >>> + struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); >>> + >>> + return vch->vrp->buf_size - sizeof(struct rpmsg_hdr); >>> +} >>> + >>> static int rpmsg_recv_single(struct virtproc_info *vrp, struct device *dev, >>> struct rpmsg_hdr *msg, unsigned int len) >>> { >>> diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h >>> index 9fe156d1c018..88d7892ca93d 100644 >>> --- a/include/linux/rpmsg.h >>> +++ b/include/linux/rpmsg.h >>> @@ -135,6 +135,8 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, >>> __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp, >>> poll_table *wait); >>> >>> +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept); >>> + >>> #else >>> >>> static inline int register_rpmsg_device(struct rpmsg_device *dev) >>> @@ -242,6 +244,14 @@ static inline __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, >>> return 0; >>> } >>> >>> +static inline ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept) >>> +{ >>> + /* This shouldn't be possible */ >>> + WARN_ON(1); >>> + >>> + return -ENXIO; >>> +} >>> + >>> #endif /* IS_ENABLED(CONFIG_RPMSG) */ >>> >>> /* use a macro to avoid include chaining to get THIS_MODULE */ >>> >
diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c index e330ec4dfc33..a6ef54c4779a 100644 --- a/drivers/rpmsg/rpmsg_core.c +++ b/drivers/rpmsg/rpmsg_core.c @@ -283,6 +283,27 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, } EXPORT_SYMBOL(rpmsg_trysend_offchannel); +/** + * rpmsg_get_mtu() - get maximum transmission buffer size for sending message. + * @ept: the rpmsg endpoint + * + * This function returns maximum buffer size available for a single message. + * + * Return: the maximum transmission size on success and an appropriate error + * value on failure. + */ + +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept) +{ + if (WARN_ON(!ept)) + return -EINVAL; + if (!ept->ops->get_mtu) + return -ENOTSUPP; + + return ept->ops->get_mtu(ept); +} +EXPORT_SYMBOL(rpmsg_get_mtu); + /* * match an rpmsg channel with a channel info struct. * this is used to make sure we're not creating rpmsg devices for channels diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h index 3fc83cd50e98..0e56e046f5c6 100644 --- a/drivers/rpmsg/rpmsg_internal.h +++ b/drivers/rpmsg/rpmsg_internal.h @@ -47,6 +47,7 @@ struct rpmsg_device_ops { * @trysendto: see @rpmsg_trysendto(), optional * @trysend_offchannel: see @rpmsg_trysend_offchannel(), optional * @poll: see @rpmsg_poll(), optional + * @get_mtu: see @get_mpu(), optional * * Indirection table for the operations that a rpmsg backend should implement. * In addition to @destroy_ept, the backend must at least implement @send and @@ -66,6 +67,7 @@ struct rpmsg_endpoint_ops { void *data, int len); __poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp, poll_table *wait); + ssize_t (*get_mtu)(struct rpmsg_endpoint *ept); }; int rpmsg_register_device(struct rpmsg_device *rpdev); diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c index 376ebbf880d6..6e48fdf24555 100644 --- a/drivers/rpmsg/virtio_rpmsg_bus.c +++ b/drivers/rpmsg/virtio_rpmsg_bus.c @@ -175,6 +175,7 @@ static int virtio_rpmsg_trysendto(struct rpmsg_endpoint *ept, void *data, int len, u32 dst); static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, void *data, int len); +static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept); static const struct rpmsg_endpoint_ops virtio_endpoint_ops = { .destroy_ept = virtio_rpmsg_destroy_ept, @@ -184,6 +185,7 @@ static const struct rpmsg_endpoint_ops virtio_endpoint_ops = { .trysend = virtio_rpmsg_trysend, .trysendto = virtio_rpmsg_trysendto, .trysend_offchannel = virtio_rpmsg_trysend_offchannel, + .get_mtu = virtio_rpmsg_get_mtu, }; /** @@ -699,6 +701,14 @@ static int virtio_rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, return rpmsg_send_offchannel_raw(rpdev, src, dst, data, len, false); } +static ssize_t virtio_rpmsg_get_mtu(struct rpmsg_endpoint *ept) +{ + struct rpmsg_device *rpdev = ept->rpdev; + struct virtio_rpmsg_channel *vch = to_virtio_rpmsg_channel(rpdev); + + return vch->vrp->buf_size - sizeof(struct rpmsg_hdr); +} + static int rpmsg_recv_single(struct virtproc_info *vrp, struct device *dev, struct rpmsg_hdr *msg, unsigned int len) { diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h index 9fe156d1c018..88d7892ca93d 100644 --- a/include/linux/rpmsg.h +++ b/include/linux/rpmsg.h @@ -135,6 +135,8 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst, __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp, poll_table *wait); +ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept); + #else static inline int register_rpmsg_device(struct rpmsg_device *dev) @@ -242,6 +244,14 @@ static inline __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, return 0; } +static inline ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept) +{ + /* This shouldn't be possible */ + WARN_ON(1); + + return -ENXIO; +} + #endif /* IS_ENABLED(CONFIG_RPMSG) */ /* use a macro to avoid include chaining to get THIS_MODULE */
Return the rpmsg buffer MTU for sending message, so rpmsg users can split a long message in several sub rpmsg buffers. Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com> --- V1 to V2 V1 patch:https://lore.kernel.org/patchwork/patch/1124684/ - Change patch title, - as not solution today to support MTU on GLINK make ops optional, RPMsg client API returns -ENOTSUPP in this case, - suppress smd and glink patches. --- drivers/rpmsg/rpmsg_core.c | 21 +++++++++++++++++++++ drivers/rpmsg/rpmsg_internal.h | 2 ++ drivers/rpmsg/virtio_rpmsg_bus.c | 10 ++++++++++ include/linux/rpmsg.h | 10 ++++++++++ 4 files changed, 43 insertions(+)