| Message ID | 20180416110428.5273-1-lszhu@suse.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 04/16/2018 06:04 AM, Zhu Lingshan wrote: > Add new netlink events helpers tcmu_netlink_event_init() and > tcmu_netlink_event_send(). These new functions intend to replace > exsiting netlink events helper function tcmu_netlink_event(). > > The exsiting function tcmu_netlink_event() works well for events > like TCMU_ADDED_DEVICE and TCMU_REMOVED_DEVICE which only has one > netlink attribute. But if there is a command requires more than > one attributes to send out, we have to use a struct to adapt the > paremeter reconfig_data, it is hard to use one struct or a union > in one struct to adapt every command with different attributes, > it may get long and ugly. > > With the new two functions, we can call tcmu_netlink_event_init() > to initialize a netlink event, then add all attributes we need by > using nla_put_xxx(), at last use tcmu_netlink_event_send() to > send it out. So that we don't need to use a long struct or union > if we want to send mulitple attributes for different commands. > > Signed-off-by: Zhu Lingshan <lszhu@suse.com> > --- > drivers/target/target_core_user.c | 57 +++++++++++++++++++++++++++++++++++++++ > 1 file changed, 57 insertions(+) > > diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c > index 4ad89ea71a70..98013d359d75 100644 > --- a/drivers/target/target_core_user.c > +++ b/drivers/target/target_core_user.c > @@ -1653,6 +1653,63 @@ static int tcmu_netlink_event(struct tcmu_dev *udev, enum tcmu_genl_cmd cmd, > return ret; > } > > +static int tcmu_netlink_event_init(struct tcmu_dev *udev, > + enum tcmu_genl_cmd cmd, > + struct sk_buff **buf, void **hdr) > +{ > + struct sk_buff *skb; > + void *msg_header; > + int ret = -ENOMEM; > + > + skb = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); > + if (!skb) > + return ret; > + > + msg_header = genlmsg_put(skb, 0, 0, &tcmu_genl_family, 0, cmd); > + if (!msg_header) > + goto free_skb; > + > + ret = nla_put_string(skb, TCMU_ATTR_DEVICE, udev->uio_info.name); > + if (ret < 0) > + goto free_skb; > + > + ret = nla_put_u32(skb, TCMU_ATTR_MINOR, udev->uio_info.uio_dev->minor); > + if (ret < 0) > + goto free_skb; > + > + ret = nla_put_u32(skb, TCMU_ATTR_DEVICE_ID, udev->se_dev.dev_index); > + if (ret < 0) > + goto free_skb; Just a nit. Add a new line here. > + *buf = skb; > + *hdr = msg_header; > + return ret; Add a newline here too. It makes it a little easier to scan the different chunks and follows the existing coding style. > +free_skb: > + nlmsg_free(skb); > + return ret; > +} > + -- To unsubscribe from this list: send the line "unsubscribe target-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index 4ad89ea71a70..98013d359d75 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -1653,6 +1653,63 @@ static int tcmu_netlink_event(struct tcmu_dev *udev, enum tcmu_genl_cmd cmd, return ret; } +static int tcmu_netlink_event_init(struct tcmu_dev *udev, + enum tcmu_genl_cmd cmd, + struct sk_buff **buf, void **hdr) +{ + struct sk_buff *skb; + void *msg_header; + int ret = -ENOMEM; + + skb = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); + if (!skb) + return ret; + + msg_header = genlmsg_put(skb, 0, 0, &tcmu_genl_family, 0, cmd); + if (!msg_header) + goto free_skb; + + ret = nla_put_string(skb, TCMU_ATTR_DEVICE, udev->uio_info.name); + if (ret < 0) + goto free_skb; + + ret = nla_put_u32(skb, TCMU_ATTR_MINOR, udev->uio_info.uio_dev->minor); + if (ret < 0) + goto free_skb; + + ret = nla_put_u32(skb, TCMU_ATTR_DEVICE_ID, udev->se_dev.dev_index); + if (ret < 0) + goto free_skb; + *buf = skb; + *hdr = msg_header; + return ret; +free_skb: + nlmsg_free(skb); + return ret; +} + +static int tcmu_netlink_event_send(struct tcmu_dev *udev, + enum tcmu_genl_cmd cmd, + struct sk_buff **buf, void **hdr) +{ + int ret = 0; + struct sk_buff *skb = *buf; + void *msg_header = *hdr; + + genlmsg_end(skb, msg_header); + + tcmu_init_genl_cmd_reply(udev, cmd); + + ret = genlmsg_multicast_allns(&tcmu_genl_family, skb, 0, + TCMU_MCGRP_CONFIG, GFP_KERNEL); + /* We don't care if no one is listening */ + if (ret == -ESRCH) + ret = 0; + if (!ret) + ret = tcmu_wait_genl_cmd_reply(udev); + return ret; +} + static int tcmu_update_uio_info(struct tcmu_dev *udev) { struct tcmu_hba *hba = udev->hba->hba_ptr;
Add new netlink events helpers tcmu_netlink_event_init() and tcmu_netlink_event_send(). These new functions intend to replace exsiting netlink events helper function tcmu_netlink_event(). The exsiting function tcmu_netlink_event() works well for events like TCMU_ADDED_DEVICE and TCMU_REMOVED_DEVICE which only has one netlink attribute. But if there is a command requires more than one attributes to send out, we have to use a struct to adapt the paremeter reconfig_data, it is hard to use one struct or a union in one struct to adapt every command with different attributes, it may get long and ugly. With the new two functions, we can call tcmu_netlink_event_init() to initialize a netlink event, then add all attributes we need by using nla_put_xxx(), at last use tcmu_netlink_event_send() to send it out. So that we don't need to use a long struct or union if we want to send mulitple attributes for different commands. Signed-off-by: Zhu Lingshan <lszhu@suse.com> --- drivers/target/target_core_user.c | 57 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+)