1cadc04c1a
Previously, the sequence number in the regulator event subsystem was updated without atomic operations, potentially leading to race conditions. This commit addresses the issue by making the sequence number atomic. Signed-off-by: Naresh Solanki <naresh.solanki@9elements.com> Link: https://msgid.link/r/20240104141314.3337037-1-naresh.solanki@9elements.com Signed-off-by: Mark Brown <broonie@kernel.org>
92 lines
2.0 KiB
C
92 lines
2.0 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Regulator event over netlink
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*
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* Author: Naresh Solanki <Naresh.Solanki@9elements.com>
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*/
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#include <regulator/regulator.h>
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#include <net/netlink.h>
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#include <net/genetlink.h>
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#include <linux/atomic.h>
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#include "regnl.h"
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static atomic_t reg_event_seqnum = ATOMIC_INIT(0);
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static const struct genl_multicast_group reg_event_mcgrps[] = {
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{ .name = REG_GENL_MCAST_GROUP_NAME, },
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};
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static struct genl_family reg_event_genl_family __ro_after_init = {
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.module = THIS_MODULE,
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.name = REG_GENL_FAMILY_NAME,
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.version = REG_GENL_VERSION,
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.maxattr = REG_GENL_ATTR_MAX,
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.mcgrps = reg_event_mcgrps,
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.n_mcgrps = ARRAY_SIZE(reg_event_mcgrps),
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};
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int reg_generate_netlink_event(const char *reg_name, u64 event)
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{
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struct sk_buff *skb;
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struct nlattr *attr;
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struct reg_genl_event *edata;
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void *msg_header;
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int size;
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/* allocate memory */
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size = nla_total_size(sizeof(struct reg_genl_event)) +
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nla_total_size(0);
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skb = genlmsg_new(size, GFP_ATOMIC);
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if (!skb)
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return -ENOMEM;
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/* add the genetlink message header */
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msg_header = genlmsg_put(skb, 0, atomic_inc_return(®_event_seqnum),
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®_event_genl_family, 0, REG_GENL_CMD_EVENT);
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if (!msg_header) {
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nlmsg_free(skb);
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return -ENOMEM;
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}
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/* fill the data */
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attr = nla_reserve(skb, REG_GENL_ATTR_EVENT, sizeof(struct reg_genl_event));
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if (!attr) {
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nlmsg_free(skb);
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return -EINVAL;
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}
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edata = nla_data(attr);
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memset(edata, 0, sizeof(struct reg_genl_event));
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strscpy(edata->reg_name, reg_name, sizeof(edata->reg_name));
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edata->event = event;
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/* send multicast genetlink message */
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genlmsg_end(skb, msg_header);
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size = genlmsg_multicast(®_event_genl_family, skb, 0, 0, GFP_ATOMIC);
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return size;
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}
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static int __init reg_event_genetlink_init(void)
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{
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return genl_register_family(®_event_genl_family);
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}
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static int __init reg_event_init(void)
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{
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int error;
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/* create genetlink for acpi event */
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error = reg_event_genetlink_init();
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if (error)
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pr_warn("Failed to create genetlink family for reg event\n");
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return 0;
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}
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fs_initcall(reg_event_init);
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