lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 4 Nov 2020 11:16:31 -0500 From: Thara Gopinath <thara.gopinath@...aro.org> To: Cristian Marussi <cristian.marussi@....com>, linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org Cc: sudeep.holla@....com, lukasz.luba@....com, james.quinlan@...adcom.com, Jonathan.Cameron@...wei.com, f.fainelli@...il.com, etienne.carriere@...aro.org, vincent.guittot@...aro.org, souvik.chakravarty@....com Subject: Re: [PATCH v2 3/8] firmware: arm_scmi: introduce new protocol operations support Hi Cristian, On 10/28/20 4:29 PM, Cristian Marussi wrote: > Expose a new generic get/put protocols API based on protocol handles; > provide also a devres managed version also for notifications. minor nit.. Maybe yous should reword this! Kind of confusing to understand! Also, if it was me, I will separate the notifications and get/put hooks into two separate patches. Not an issue though if you want to keep it in the same patch. > All SCMI drivers still keep using the old handle based interface. > > Signed-off-by: Cristian Marussi <cristian.marussi@....com> > --- > drivers/firmware/arm_scmi/driver.c | 126 +++++++++++++++++++++++++++++ > drivers/firmware/arm_scmi/notify.c | 123 ++++++++++++++++++++++++++++ > include/linux/scmi_protocol.h | 34 +++++++- > 3 files changed, 282 insertions(+), 1 deletion(-) > > diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c > index 8ca04acb6abb..4d86aafbf465 100644 > --- a/drivers/firmware/arm_scmi/driver.c > +++ b/drivers/firmware/arm_scmi/driver.c > @@ -15,6 +15,7 @@ > */ > > #include <linux/bitmap.h> > +#include <linux/device.h> > #include <linux/export.h> > #include <linux/idr.h> > #include <linux/io.h> > @@ -728,6 +729,38 @@ void scmi_release_protocol(struct scmi_handle *handle, u8 protocol_id) > mutex_unlock(&info->protocols_mtx); > } > > +/** > + * scmi_get_protocol_operations - Get protocol operations > + * @handle: A reference to the SCMI platform instance. > + * @protocol_id: The protocol being requested. > + * @ph: A pointer reference used to pass back the associated protocol handle. > + * > + * Get hold of a protocol accounting for its usage, eventually triggering its > + * initialization, and returning the protocol specific operations and related > + * protocol handle which will be used as first argument in most of the protocols > + * operations methods. > + * > + * Return: A reference to the requested protocol operations or error. > + * Must be checked for errors by caller. > + */ > +static const void __must_check * > +scmi_get_protocol_operations(struct scmi_handle *handle, u8 protocol_id, > + struct scmi_protocol_handle **ph) > +{ > + struct scmi_protocol_instance *pi; > + > + if (!ph) > + return ERR_PTR(-EINVAL); > + > + pi = scmi_get_protocol_instance(handle, protocol_id); > + if (IS_ERR(pi)) > + return pi; > + > + *ph = &pi->ph; > + > + return pi->proto->ops; > +} > + > void scmi_setup_protocol_implemented(const struct scmi_handle *handle, > u8 *prot_imp) > { > @@ -751,6 +784,95 @@ scmi_is_protocol_implemented(const struct scmi_handle *handle, u8 prot_id) > return false; > } > > +struct scmi_protocol_devres { > + struct scmi_handle *handle; > + u8 protocol_id; > +}; > + > +static void scmi_devm_release_protocol(struct device *dev, void *res) > +{ > + struct scmi_protocol_devres *dres = res; > + > + scmi_release_protocol(dres->handle, dres->protocol_id); > +} > + > +/** > + * scmi_devm_get_protocol_ops - Devres managed get protocol operations > + * @sdev: A reference to an scmi_device whose embedded struct device is to > + * be used for devres accounting. > + * @protocol_id: The protocol being requested. > + * @ph: A pointer reference used to pass back the associated protocol handle. > + * > + * Get hold of a protocol accounting for its usage, eventually triggering its > + * initialization, and returning the protocol specific operations and related > + * protocol handle which will be used as first argument in most of the > + * protocols operations methods. > + * Being a devres based managed method, protocol hold will be automatically > + * released, and possibly de-initialized on last user, once the SCMI driver > + * owning the scmi_device is unbound from it. > + * > + * Return: A reference to the requested protocol operations or error. > + * Must be checked for errors by caller. > + */ > +static const void __must_check * > +scmi_devm_get_protocol_ops(struct scmi_device *sdev, u8 protocol_id, > + struct scmi_protocol_handle **ph) > +{ > + struct scmi_protocol_instance *pi; > + struct scmi_protocol_devres *dres; > + struct scmi_handle *handle = sdev->handle; > + > + if (!ph) > + return ERR_PTR(-EINVAL); > + > + dres = devres_alloc(scmi_devm_release_protocol, > + sizeof(*dres), GFP_KERNEL); > + if (!dres) > + return ERR_PTR(-ENOMEM); > + > + pi = scmi_get_protocol_instance(handle, protocol_id); > + if (IS_ERR(pi)) { > + devres_free(dres); > + return pi; > + } > + > + dres->handle = handle; > + dres->protocol_id = protocol_id; > + devres_add(&sdev->dev, dres); > + > + *ph = &pi->ph; > + > + return pi->proto->ops; > +} > + > +static int scmi_devm_protocol_match(struct device *dev, void *res, void *data) > +{ > + struct scmi_protocol_devres *dres = res; > + > + if (WARN_ON(!dres || !data)) > + return 0; > + > + return dres->protocol_id == *((u8 *)data); > +} > + > +/** > + * scmi_devm_put_protocol_ops - Devres managed put protocol operations > + * @sdev: A reference to an scmi_device whose embedded struct device is to > + * be used for devres accounting. > + * @protocol_id: The protocol being requested. > + * > + * Explicitly release a protocol hold previously obtained calling the above > + * @scmi_devm_get_protocol_ops. > + */ > +static void scmi_devm_put_protocol_ops(struct scmi_device *sdev, u8 protocol_id) > +{ > + int ret; > + > + ret = devres_release(&sdev->dev, scmi_devm_release_protocol, > + scmi_devm_protocol_match, &protocol_id); > + WARN_ON(ret); > +} > + > /** > * scmi_handle_get() - Get the SCMI handle for a device > * > @@ -1004,6 +1126,10 @@ static int scmi_probe(struct platform_device *pdev) > handle = &info->handle; > handle->dev = info->dev; > handle->version = &info->version; > + handle->devm_get_ops = scmi_devm_get_protocol_ops; > + handle->devm_put_ops = scmi_devm_put_protocol_ops; > + handle->get_ops = scmi_get_protocol_operations; > + handle->put_ops = scmi_release_protocol; Why do you need a dev_res version and a non dev_res version? I checked patch 6 where you convert the drivers to use these hooks and all of them are using the dev res apis. > > ret = scmi_txrx_setup(info, dev, SCMI_PROTOCOL_BASE); > if (ret) > diff --git a/drivers/firmware/arm_scmi/notify.c b/drivers/firmware/arm_scmi/notify.c > index eae58b2a92cc..64d43e425644 100644 > --- a/drivers/firmware/arm_scmi/notify.c > +++ b/drivers/firmware/arm_scmi/notify.c > @@ -1370,6 +1370,127 @@ static int scmi_unregister_notifier(const struct scmi_handle *handle, > return 0; > } > > +struct scmi_notifier_devres { > + const struct scmi_handle *handle; > + u8 proto_id; > + u8 evt_id; > + u32 __src_id; > + u32 *src_id; Instead of maintaining two separate pointers for src id, why not define a bool, something like is_src_id_valid? Should simply this a bit and also don't have to maintain two 32 bit pointers. What do you think? > + struct notifier_block *nb; > +}; > + > +static void scmi_devm_release_notifier(struct device *dev, void *res) > +{ > + struct scmi_notifier_devres *dres = res; > + > + scmi_unregister_notifier(dres->handle, dres->proto_id, dres->evt_id, > + dres->src_id, dres->nb); > +} > + > +/** > + * scmi_devm_register_notifier() - Managed registration of a notifier_block > + * for an event > + * @sdev: A reference to an scmi_device whose embedded struct device is to > + * be used for devres accounting. > + * @proto_id: Protocol ID > + * @evt_id: Event ID > + * @src_id: Source ID, when NULL register for events coming form ALL possible > + * sources > + * @nb: A standard notifier block to register for the specified event > + * > + * Generic devres managed helper to register a notifier_block against a > + * protocol event. > + */ > +static int scmi_devm_register_notifier(struct scmi_device *sdev, > + u8 proto_id, u8 evt_id, u32 *src_id, > + struct notifier_block *nb) > +{ > + int ret; > + struct scmi_notifier_devres *dres; > + > + dres = devres_alloc(scmi_devm_release_notifier, > + sizeof(*dres), GFP_KERNEL); > + if (!dres) > + return -ENOMEM; > + > + ret = scmi_register_notifier(sdev->handle, proto_id, > + evt_id, src_id, nb); > + if (ret) { > + devres_free(dres); > + return ret; > + } > + > + dres->handle = sdev->handle; > + dres->proto_id = proto_id; > + dres->evt_id = evt_id; > + dres->nb = nb; > + if (src_id) { > + dres->__src_id = *src_id; > + dres->src_id = &dres->__src_id; > + } else { > + dres->src_id = NULL; > + } > + devres_add(&sdev->dev, dres); > + > + return ret; > +} > + > +static int scmi_devm_notifier_match(struct device *dev, void *res, void *data) > +{ > + struct scmi_notifier_devres *dres = res; > + struct scmi_notifier_devres *xres = data; > + > + if (WARN_ON(!dres || !xres)) > + return 0; > + > + return dres->proto_id == xres->proto_id && > + dres->evt_id == xres->evt_id && > + dres->nb == xres->nb && Does the nb have to be compared as well ? > + ((!dres->src_id && !xres->src_id) || > + (dres->src_id && xres->src_id && > + dres->__src_id == xres->__src_id)); -- Warm Regards Thara
Powered by blists - more mailing lists