Return-path: Received: from mail-yi0-f46.google.com ([209.85.218.46]:48813 "EHLO mail-yi0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752255Ab1FUWEy (ORCPT ); Tue, 21 Jun 2011 18:04:54 -0400 Received: by yia27 with SMTP id 27so96214yia.19 for ; Tue, 21 Jun 2011 15:04:53 -0700 (PDT) Date: Tue, 21 Jun 2011 19:05:10 -0300 From: "Gustavo F. Padovan" To: Aloisio Almeida Jr Cc: linville@tuxdriver.com, linux-wireless@vger.kernel.org, sameo@linux.intel.com, johannes@sipsolutions.net, lauro.venancio@openbossa.org, marcio.macedo@openbossa.org, Waldemar.Rymarkiewicz@tieto.com Subject: Re: [RFC][PATCH v2 3/7] NFC: add nfc generic netlink interface Message-ID: <20110621220510.GG2628@joana> (sfid-20110622_000457_895681_E85C861D) References: <1308592212-5755-1-git-send-email-aloisio.almeida@openbossa.org> <1308592212-5755-4-git-send-email-aloisio.almeida@openbossa.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1308592212-5755-4-git-send-email-aloisio.almeida@openbossa.org> Sender: linux-wireless-owner@vger.kernel.org List-ID: * Aloisio Almeida Jr [2011-06-20 14:50:08 -0300]: > From: Lauro Ramos Venancio > > The NFC generic netlink interface exports the NFC control operations > to the user space. > > Signed-off-by: Lauro Ramos Venancio > Signed-off-by: Aloisio Almeida Jr > Signed-off-by: Samuel Ortiz > --- > include/linux/nfc.h | 111 +++++++++++ > include/net/nfc.h | 21 ++ > net/nfc/Makefile | 2 +- > net/nfc/core.c | 83 ++++++++- > net/nfc/netlink.c | 537 +++++++++++++++++++++++++++++++++++++++++++++++++++ > net/nfc/nfc.h | 11 + > 6 files changed, 762 insertions(+), 3 deletions(-) > create mode 100644 include/linux/nfc.h > create mode 100644 net/nfc/netlink.c > > diff --git a/include/linux/nfc.h b/include/linux/nfc.h > new file mode 100644 > index 0000000..59b3c79 > --- /dev/null > +++ b/include/linux/nfc.h > @@ -0,0 +1,111 @@ > +/* > + * Copyright (C) 2011 Instituto Nokia de Tecnologia > + * > + * Authors: > + * Lauro Ramos Venancio > + * Aloisio Almeida Jr > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; if not, write to the > + * Free Software Foundation, Inc., > + * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. > + */ > + > +#ifndef __LINUX_NFC_H > +#define __LINUX_NFC_H > + > +#define NFC_GENL_NAME "nfc" > +#define NFC_GENL_VERSION 1 > + > +#define NFC_GENL_MCAST_EVENT_NAME "events" > + > +/** > + * enum nfc_commands - supported nfc commands > + * > + * @NFC_CMD_UNSPEC: unspecified command > + * > + * @NFC_CMD_GET_DEVICE: request information about a device (requires > + * %NFC_ATTR_DEVICE_INDEX) or dump request to get a list of all nfc devices > + * @NFC_CMD_START_POLL: start polling for targets using the given protocols > + * (requires %NFC_ATTR_DEVICE_INDEX and %NFC_ATTR_PROTOCOLS) > + * @NFC_CMD_STOP_POLL: stop polling for targets (requires > + * %NFC_ATTR_DEVICE_INDEX) > + * @NFC_CMD_GET_TARGET: dump all targets found by the previous poll (requires > + * %NFC_ATTR_DEVICE_INDEX) > + * @NFC_EVENT_TARGETS_FOUND: event emitted when a new target is found > + * (it sends %NFC_ATTR_DEVICE_INDEX) > + * @NFC_EVENT_DEVICE_ADDED: event emitted when a new device is registred > + * (it sends %NFC_ATTR_DEVICE_NAME, %NFC_ATTR_DEVICE_INDEX and > + * %NFC_ATTR_PROTOCOLS) > + * @NFC_EVENT_DEVICE_REMOVED: event emitted when a device is removed > + * (it sends %NFC_ATTR_DEVICE_INDEX) > + */ > +enum nfc_commands { > + NFC_CMD_UNSPEC, > + NFC_CMD_GET_DEVICE, > + NFC_CMD_START_POLL, > + NFC_CMD_STOP_POLL, > + NFC_CMD_GET_TARGET, > + NFC_EVENT_TARGETS_FOUND, > + NFC_EVENT_DEVICE_ADDED, > + NFC_EVENT_DEVICE_REMOVED, > +/* private: internal use only */ > + __NFC_CMD_AFTER_LAST > +}; > +#define NFC_CMD_MAX (__NFC_CMD_AFTER_LAST - 1) > + > +/** > + * enum nfc_attrs - supported nfc attributes > + * > + * @NFC_ATTR_UNSPEC: unspecified attribute > + * > + * @NFC_ATTR_DEVICE_INDEX: index of nfc device > + * @NFC_ATTR_DEVICE_NAME: device name, max 8 chars > + * @NFC_ATTR_PROTOCOLS: nfc protocols - bitwise or-ed combination from > + * NFC_PROTO_*_MASK constants > + * @NFC_ATTR_TARGET_INDEX: index of the nfc target > + * @NFC_ATTR_TARGET_SENS_RES: extra information for NFC-A targets > + * @NFC_ATTR_TARGET_SEL_RES: extra information for NFC-A targets > + */ > +enum nfc_attrs { > + NFC_ATTR_UNSPEC, > + NFC_ATTR_DEVICE_INDEX, > + NFC_ATTR_DEVICE_NAME, > + NFC_ATTR_PROTOCOLS, > + NFC_ATTR_TARGET_INDEX, > + NFC_ATTR_TARGET_SENS_RES, > + NFC_ATTR_TARGET_SEL_RES, > +/* private: internal use only */ > + __NFC_ATTR_AFTER_LAST > +}; > +#define NFC_ATTR_MAX (__NFC_ATTR_AFTER_LAST - 1) > + > +#define NFC_DEVICE_NAME_MAXSIZE 8 > + > +/* NFC protocols */ > +#define NFC_PROTO_JEWEL 0 > +#define NFC_PROTO_MIFARE 1 > +#define NFC_PROTO_FELICA 2 > +#define NFC_PROTO_ISO14443 3 > +#define NFC_PROTO_NFC_DEP 4 > + > +#define NFC_PROTO_MAX 5 > + > +/* NFC protocols masks used in bitsets */ > +#define NFC_PROTO_JEWEL_MASK (1 << NFC_PROTO_JEWEL) > +#define NFC_PROTO_MIFARE_MASK (1 << NFC_PROTO_MIFARE) > +#define NFC_PROTO_FELICA_MASK (1 << NFC_PROTO_FELICA) > +#define NFC_PROTO_ISO14443_MASK (1 << NFC_PROTO_ISO14443) > +#define NFC_PROTO_NFC_DEP_MASK (1 << NFC_PROTO_NFC_DEP) > + > +#endif /*__LINUX_NFC_H */ > diff --git a/include/net/nfc.h b/include/net/nfc.h > index 11d63dc..01a30b3 100644 > --- a/include/net/nfc.h > +++ b/include/net/nfc.h > @@ -54,10 +54,28 @@ struct nfc_ops { > void *cb_context); > }; > > +struct nfc_target { > + u32 idx; > + u32 supported_protocols; > + u16 sens_res; > + u8 sel_res; > +}; > + > +struct nfc_genl_data { > + u32 poll_req_pid; > + struct mutex genl_data_mutex; > +}; > + > struct nfc_dev { > unsigned idx; > + unsigned target_idx; > + struct nfc_target *targets; > + int n_targets; > + int targets_generation; > + spinlock_t targets_lock; > struct device dev; > bool polling; > + struct nfc_genl_data genl_data; > u32 supported_protocols; > > struct nfc_ops *ops; > @@ -128,4 +146,7 @@ static inline const char *nfc_device_name(struct nfc_dev *dev) > > struct sk_buff *nfc_alloc_skb(unsigned int size, gfp_t gfp); > > +int nfc_targets_found(struct nfc_dev *dev, struct nfc_target *targets, > + int ntargets); > + > #endif /* __NET_NFC_H */ > diff --git a/net/nfc/Makefile b/net/nfc/Makefile > index d837743..8aeaddc 100644 > --- a/net/nfc/Makefile > +++ b/net/nfc/Makefile > @@ -4,6 +4,6 @@ > > obj-$(CONFIG_NFC) += nfc.o > > -nfc-objs := core.o > +nfc-objs := core.o netlink.o > > ccflags-$(CONFIG_NFC_DEBUG) := -DDEBUG > diff --git a/net/nfc/core.c b/net/nfc/core.c > index f4710fe..5e09d50 100644 > --- a/net/nfc/core.c > +++ b/net/nfc/core.c > @@ -213,12 +213,61 @@ struct sk_buff *nfc_alloc_skb(unsigned int size, gfp_t gfp) > } > EXPORT_SYMBOL(nfc_alloc_skb); > > +/** > + * nfc_targets_found - inform that targets were found > + * > + * @dev: The nfc device that found the targets > + * @targets: array of nfc targets found > + * @ntargets: targets array size > + * > + * The device driver must call this function when one or many nfc targets > + * are found. After calling this function, the device driver must stop > + * polling for targets. > + */ > +int nfc_targets_found(struct nfc_dev *dev, struct nfc_target *targets, > + int n_targets) > +{ > + int i; > + > + pr_debug("%s: dev_name:%s", __func__, dev_name(&dev->dev)); > + > + dev->polling = false; > + > + for (i = 0; i < n_targets; i++) > + targets[i].idx = dev->target_idx++; > + > + spin_lock_bh(&dev->targets_lock); > + > + dev->targets_generation++; > + > + kfree(dev->targets); > + dev->targets = kzalloc(n_targets * sizeof(struct nfc_target), > + GFP_ATOMIC); > + if (!dev->targets) { > + dev->n_targets = 0; > + spin_unlock_bh(&dev->targets_lock); > + return -ENOMEM; > + } > + > + memcpy(dev->targets, targets, n_targets * sizeof(struct nfc_target)); > + dev->n_targets = n_targets; > + > + spin_unlock_bh(&dev->targets_lock); > + > + nfc_genl_targets_found(dev); > + > + return 0; > +} > +EXPORT_SYMBOL(nfc_targets_found); > + > static void nfc_release(struct device *d) > { > struct nfc_dev *dev = to_nfc_dev(d); > > pr_debug("%s: dev_name:%s", __func__, dev_name(&dev->dev)); > > + nfc_genl_data_exit(&dev->genl_data); > + kfree(dev->targets); > kfree(dev); > } > > @@ -278,6 +327,12 @@ struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops, > dev->ops = ops; > dev->supported_protocols = supported_protocols; > > + spin_lock_init(&dev->targets_lock); > + nfc_genl_data_init(&dev->genl_data); > + > + /* first generation must not be 0 */ > + dev->targets_generation = 1; > + > return dev; > } > EXPORT_SYMBOL(nfc_allocate_device); > @@ -298,7 +353,10 @@ int nfc_register_device(struct nfc_dev *dev) > rc = device_add(&dev->dev); > mutex_unlock(&nfc_devlist_mutex); > > - return rc; > + if (rc < 0) > + return rc; > + > + return nfc_genl_device_added(dev); > } > EXPORT_SYMBOL(nfc_register_device); > > @@ -321,18 +379,39 @@ void nfc_unregister_device(struct nfc_dev *dev) > device_unlock(&dev->dev); > > mutex_unlock(&nfc_devlist_mutex); > + > + nfc_genl_device_removed(dev); > } > EXPORT_SYMBOL(nfc_unregister_device); > > static int __init nfc_init(void) > { > + int rc; > + > printk(KERN_INFO "NFC Core ver %s\n", VERSION); > > - return class_register(&nfc_class); > + rc = class_register(&nfc_class); > + if (rc) > + goto err; Just return rc here and get rid of the label. > + > + rc = nfc_genl_init(); > + if (rc) > + goto err_genl; > + > + /* the first generation must not be 0 */ > + nfc_devlist_generation = 1; > + > + return 0; > + > +err_genl: > + class_unregister(&nfc_class); > +err: > + return rc; > } > > static void __exit nfc_exit(void) > { > + nfc_genl_exit(); > class_unregister(&nfc_class); > } > > diff --git a/net/nfc/netlink.c b/net/nfc/netlink.c > new file mode 100644 > index 0000000..5f2ddb2 > --- /dev/null > +++ b/net/nfc/netlink.c > @@ -0,0 +1,537 @@ > +/* > + * Copyright (C) 2011 Instituto Nokia de Tecnologia > + * > + * Authors: > + * Lauro Ramos Venancio > + * Aloisio Almeida Jr > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program; if not, write to the > + * Free Software Foundation, Inc., > + * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. > + */ > + > +#include > +#include > +#include > + > +#include "nfc.h" > + > +static struct genl_multicast_group nfc_genl_event_mcgrp = { > + .name = NFC_GENL_MCAST_EVENT_NAME, > +}; > + > +struct genl_family nfc_genl_family = { > + .id = GENL_ID_GENERATE, > + .hdrsize = 0, > + .name = NFC_GENL_NAME, > + .version = NFC_GENL_VERSION, > + .maxattr = NFC_ATTR_MAX, > +}; > + > +static const struct nla_policy nfc_genl_policy[NFC_ATTR_MAX + 1] = { > + [NFC_ATTR_DEVICE_INDEX] = { .type = NLA_U32 }, > + [NFC_ATTR_DEVICE_NAME] = { .type = NLA_STRING, > + .len = NFC_DEVICE_NAME_MAXSIZE }, > + [NFC_ATTR_PROTOCOLS] = { .type = NLA_U32 }, > +}; > + > +static int nfc_genl_send_target(struct sk_buff *msg, struct nfc_target *target, > + struct netlink_callback *cb, int flags) > +{ > + void *hdr; > + > + pr_debug("%s\n", __func__); > + > + hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq, > + &nfc_genl_family, flags, NFC_CMD_GET_TARGET); > + if (!hdr) > + return -EMSGSIZE; > + > + genl_dump_check_consistent(cb, hdr, &nfc_genl_family); > + > + NLA_PUT_U32(msg, NFC_ATTR_TARGET_INDEX, target->idx); > + NLA_PUT_U32(msg, NFC_ATTR_PROTOCOLS, > + target->supported_protocols); > + NLA_PUT_U16(msg, NFC_ATTR_TARGET_SENS_RES, target->sens_res); > + NLA_PUT_U8(msg, NFC_ATTR_TARGET_SEL_RES, target->sel_res); > + > + return genlmsg_end(msg, hdr); > + > +nla_put_failure: There is no use for this macro in all function that have a label with this name. > + genlmsg_cancel(msg, hdr); > + return -EMSGSIZE; > +} > + > +static struct nfc_dev *__get_device_from_cb(struct netlink_callback *cb) > +{ > + struct nfc_dev *dev; > + int rc; > + u32 idx; > + > + rc = nlmsg_parse(cb->nlh, GENL_HDRLEN + nfc_genl_family.hdrsize, > + nfc_genl_family.attrbuf, > + nfc_genl_family.maxattr, > + nfc_genl_policy); > + if (rc < 0) > + return ERR_PTR(rc); > + > + if (!nfc_genl_family.attrbuf[NFC_ATTR_DEVICE_INDEX]) > + return ERR_PTR(-EINVAL); > + > + idx = nla_get_u32(nfc_genl_family.attrbuf[NFC_ATTR_DEVICE_INDEX]); > + > + dev = nfc_get_device(idx); > + if (!dev) > + return ERR_PTR(-ENODEV); > + > + return dev; > +} > + > +static int nfc_genl_dump_targets(struct sk_buff *skb, > + struct netlink_callback *cb) > +{ > + int i = cb->args[0]; > + struct nfc_dev *dev = (struct nfc_dev *) cb->args[1]; > + int rc; > + > + pr_debug("%s\n", __func__); > + > + if (!dev) { > + dev = __get_device_from_cb(cb); > + if (IS_ERR(dev)) > + return PTR_ERR(dev); > + > + cb->args[1] = (long) dev; > + } > + > + spin_lock_bh(&dev->targets_lock); > + > + cb->seq = dev->targets_generation; > + > + while (i < dev->n_targets) { > + rc = nfc_genl_send_target(skb, &dev->targets[i], cb, > + NLM_F_MULTI); > + if (rc < 0) > + break; > + > + i++; > + } > + > + spin_unlock_bh(&dev->targets_lock); > + > + cb->args[0] = i; > + > + return skb->len; > +} > + > +static int nfc_genl_dump_targets_done(struct netlink_callback *cb) > +{ > + struct nfc_dev *dev = (struct nfc_dev *) cb->args[1]; > + > + pr_debug("%s\n", __func__); > + > + if (dev) > + nfc_put_device(dev); > + > + return 0; > +} > + > +int nfc_genl_targets_found(struct nfc_dev *dev) > +{ > + struct sk_buff *msg; > + void *hdr; > + > + pr_debug("%s\n", __func__); > + > + dev->genl_data.poll_req_pid = 0; > + > + msg = nlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC); > + if (!msg) > + return -ENOMEM; > + > + hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0, > + NFC_EVENT_TARGETS_FOUND); > + if (!hdr) > + goto free_msg; > + > + NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx); > + > + genlmsg_end(msg, hdr); > + > + return genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_ATOMIC); > + > +nla_put_failure: > + genlmsg_cancel(msg, hdr); > +free_msg: > + nlmsg_free(msg); > + return -EMSGSIZE; > +} > + > +int nfc_genl_device_added(struct nfc_dev *dev) > +{ > + struct sk_buff *msg; > + void *hdr; > + > + pr_debug("%s\n", __func__); > + > + msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); > + if (!msg) > + return -ENOMEM; > + > + hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0, > + NFC_EVENT_DEVICE_ADDED); > + if (!hdr) > + goto free_msg; > + > + NLA_PUT_STRING(msg, NFC_ATTR_DEVICE_NAME, nfc_device_name(dev)); > + NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx); > + NLA_PUT_U32(msg, NFC_ATTR_PROTOCOLS, dev->supported_protocols); > + > + genlmsg_end(msg, hdr); > + > + genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_KERNEL); > + > + return 0; > + > +nla_put_failure: > + genlmsg_cancel(msg, hdr); > +free_msg: > + nlmsg_free(msg); > + return -EMSGSIZE; > +} > + > +int nfc_genl_device_removed(struct nfc_dev *dev) > +{ > + struct sk_buff *msg; > + void *hdr; > + > + pr_debug("%s\n", __func__); > + > + msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); > + if (!msg) > + return -ENOMEM; > + > + hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0, > + NFC_EVENT_DEVICE_REMOVED); > + if (!hdr) > + goto free_msg; > + > + NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx); > + > + genlmsg_end(msg, hdr); > + > + genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_KERNEL); > + > + return 0; > + > +nla_put_failure: > + genlmsg_cancel(msg, hdr); > +free_msg: > + nlmsg_free(msg); > + return -EMSGSIZE; > +} > + > +static int nfc_genl_send_device(struct sk_buff *msg, struct nfc_dev *dev, > + u32 pid, u32 seq, > + struct netlink_callback *cb, > + int flags) > +{ > + void *hdr; > + > + pr_debug("%s\n", __func__); > + > + hdr = genlmsg_put(msg, pid, seq, &nfc_genl_family, flags, > + NFC_CMD_GET_DEVICE); > + if (!hdr) > + return -EMSGSIZE; > + > + if (cb) > + genl_dump_check_consistent(cb, hdr, &nfc_genl_family); > + > + NLA_PUT_STRING(msg, NFC_ATTR_DEVICE_NAME, nfc_device_name(dev)); > + NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx); > + NLA_PUT_U32(msg, NFC_ATTR_PROTOCOLS, dev->supported_protocols); > + > + return genlmsg_end(msg, hdr); > + > +nla_put_failure: > + genlmsg_cancel(msg, hdr); > + return -EMSGSIZE; > +} > + > +static int nfc_genl_dump_devices(struct sk_buff *skb, > + struct netlink_callback *cb) > +{ > + struct class_dev_iter *iter = (struct class_dev_iter *) cb->args[0]; > + struct nfc_dev *dev = (struct nfc_dev *) cb->args[1]; > + bool first_call = false; > + > + pr_debug("%s\n", __func__); > + > + if (!iter) { > + first_call = true; > + iter = kmalloc(sizeof(struct class_dev_iter), GFP_KERNEL); > + if (!iter) > + return -ENOMEM; > + cb->args[0] = (long) iter; > + } > + > + mutex_lock(&nfc_devlist_mutex); > + > + cb->seq = nfc_devlist_generation; > + > + if (first_call) { > + nfc_device_iter_init(iter); > + dev = nfc_device_iter_next(iter); > + } > + > + while (dev) { > + int rc; > + > + rc = nfc_genl_send_device(skb, dev, NETLINK_CB(cb->skb).pid, > + cb->nlh->nlmsg_seq, > + cb, NLM_F_MULTI); > + if (rc < 0) > + break; > + > + dev = nfc_device_iter_next(iter); > + } > + > + mutex_unlock(&nfc_devlist_mutex); > + > + cb->args[1] = (long) dev; > + > + return skb->len; > +} > + > +static int nfc_genl_dump_devices_done(struct netlink_callback *cb) > +{ > + struct class_dev_iter *iter = (struct class_dev_iter *) cb->args[0]; > + > + pr_debug("%s\n", __func__); > + > + nfc_device_iter_exit(iter); > + kfree(iter); > + > + return 0; > +} > + > +static int nfc_genl_get_device(struct sk_buff *skb, struct genl_info *info) > +{ > + struct sk_buff *msg; > + struct nfc_dev *dev; > + u32 idx; > + int rc = -ENOBUFS; > + > + pr_debug("%s\n", __func__); > + > + if (!info->attrs[NFC_ATTR_DEVICE_INDEX]) > + return -EINVAL; > + > + idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]); > + > + dev = nfc_get_device(idx); > + if (!dev) > + return -ENODEV; > + > + msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); > + if (!msg) { > + rc = -ENOMEM; > + goto out_putdev; > + } > + > + rc = nfc_genl_send_device(msg, dev, info->snd_pid, info->snd_seq, > + NULL, 0); > + if (rc < 0) > + goto out_free; > + > + nfc_put_device(dev); > + > + return genlmsg_reply(msg, info); > + > +out_free: > + nlmsg_free(msg); > +out_putdev: > + nfc_put_device(dev); > + return rc; > +} > + > +static int nfc_genl_start_poll(struct sk_buff *skb, struct genl_info *info) > +{ > + struct nfc_dev *dev; > + int rc; > + u32 idx; > + u32 protocols; > + > + pr_debug("%s\n", __func__); > + > + if (!info->attrs[NFC_ATTR_DEVICE_INDEX] || > + !info->attrs[NFC_ATTR_PROTOCOLS]) > + return -EINVAL; > + > + idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]); > + protocols = nla_get_u32(info->attrs[NFC_ATTR_PROTOCOLS]); > + > + dev = nfc_get_device(idx); > + if (!dev) > + return -ENODEV; > + > + mutex_lock(&dev->genl_data.genl_data_mutex); > + > + rc = nfc_start_poll(dev, protocols); > + if (!rc) > + dev->genl_data.poll_req_pid = info->snd_pid; > + > + mutex_unlock(&dev->genl_data.genl_data_mutex); > + > + nfc_put_device(dev); > + return rc; > +} > + > +static int nfc_genl_stop_poll(struct sk_buff *skb, struct genl_info *info) > +{ > + struct nfc_dev *dev; > + int rc; > + u32 idx; > + > + pr_debug("%s\n", __func__); > + > + if (!info->attrs[NFC_ATTR_DEVICE_INDEX]) > + return -EINVAL; > + > + idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]); > + > + dev = nfc_get_device(idx); > + if (!dev) > + return -ENODEV; > + > + mutex_lock(&dev->genl_data.genl_data_mutex); > + > + if (dev->genl_data.poll_req_pid != info->snd_pid) { > + rc = -EBUSY; > + goto out; > + } > + > + rc = nfc_stop_poll(dev); > + dev->genl_data.poll_req_pid = 0; > + > +out: > + mutex_unlock(&dev->genl_data.genl_data_mutex); > + nfc_put_device(dev); > + return rc; > +} > + > +static struct genl_ops nfc_genl_ops[] = { > + { > + .cmd = NFC_CMD_GET_DEVICE, > + .doit = nfc_genl_get_device, > + .dumpit = nfc_genl_dump_devices, > + .done = nfc_genl_dump_devices_done, > + .policy = nfc_genl_policy, > + }, > + { > + .cmd = NFC_CMD_START_POLL, > + .doit = nfc_genl_start_poll, > + .policy = nfc_genl_policy, > + }, > + { > + .cmd = NFC_CMD_STOP_POLL, > + .doit = nfc_genl_stop_poll, > + .policy = nfc_genl_policy, > + }, > + { > + .cmd = NFC_CMD_GET_TARGET, > + .dumpit = nfc_genl_dump_targets, > + .done = nfc_genl_dump_targets_done, > + .policy = nfc_genl_policy, > + }, > +}; > + > +static int nfc_genl_rcv_nl_event(struct notifier_block *this, > + unsigned long event, void *ptr) > +{ > + struct netlink_notify *n = ptr; > + struct class_dev_iter iter; > + struct nfc_dev *dev; > + > + if (event != NETLINK_URELEASE || n->protocol != NETLINK_GENERIC) > + goto out; > + > + pr_debug("%s: NETLINK_URELEASE event from id %d\n", __func__, n->pid); > + > + nfc_device_iter_init(&iter); > + dev = nfc_device_iter_next(&iter); > + > + while (dev) { > + mutex_lock(&dev->genl_data.genl_data_mutex); > + if (dev->genl_data.poll_req_pid == n->pid) { > + nfc_stop_poll(dev); > + dev->genl_data.poll_req_pid = 0; > + } > + mutex_unlock(&dev->genl_data.genl_data_mutex); > + dev = nfc_device_iter_next(&iter); > + } > + > + nfc_device_iter_exit(&iter); > + > +out: > + return NOTIFY_DONE; > +} > + > +void nfc_genl_data_init(struct nfc_genl_data *genl_data) > +{ > + genl_data->poll_req_pid = 0; > + mutex_init(&genl_data->genl_data_mutex); > +} > + > +void nfc_genl_data_exit(struct nfc_genl_data *genl_data) > +{ > + mutex_destroy(&genl_data->genl_data_mutex); > +} > + > +static struct notifier_block nl_notifier = { > + .notifier_call = nfc_genl_rcv_nl_event, > +}; > + > +/** > + * nfc_genl_init() - Initialize netlink interface > + * > + * This initialization function registers the nfc netlink family. > + */ > +int __init nfc_genl_init(void) > +{ > + int rc; > + > + rc = genl_register_family_with_ops(&nfc_genl_family, nfc_genl_ops, > + ARRAY_SIZE(nfc_genl_ops)); > + if (rc) > + return rc; > + > + rc = genl_register_mc_group(&nfc_genl_family, &nfc_genl_event_mcgrp); > + > + netlink_register_notifier(&nl_notifier); > + > + return rc; > +} > + > +/** > + * nfc_genl_exit() - Deinitialize netlink interface > + * > + * This exit function unregisters the nfc netlink family. > + */ > +void nfc_genl_exit(void) You may want __exit here. Gustavo