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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/connector/cn_queue.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/connector/cn_queue.c')
-rw-r--r-- | drivers/connector/cn_queue.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/drivers/connector/cn_queue.c b/drivers/connector/cn_queue.c new file mode 100644 index 000000000..996f025eb --- /dev/null +++ b/drivers/connector/cn_queue.c @@ -0,0 +1,147 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * cn_queue.c + * + * 2004+ Copyright (c) Evgeniy Polyakov <zbr@ioremap.net> + * All rights reserved. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/list.h> +#include <linux/workqueue.h> +#include <linux/spinlock.h> +#include <linux/slab.h> +#include <linux/skbuff.h> +#include <linux/suspend.h> +#include <linux/connector.h> +#include <linux/delay.h> + +static struct cn_callback_entry * +cn_queue_alloc_callback_entry(struct cn_queue_dev *dev, const char *name, + const struct cb_id *id, + void (*callback)(struct cn_msg *, + struct netlink_skb_parms *)) +{ + struct cn_callback_entry *cbq; + + cbq = kzalloc(sizeof(*cbq), GFP_KERNEL); + if (!cbq) { + pr_err("Failed to create new callback queue.\n"); + return NULL; + } + + refcount_set(&cbq->refcnt, 1); + + atomic_inc(&dev->refcnt); + cbq->pdev = dev; + + snprintf(cbq->id.name, sizeof(cbq->id.name), "%s", name); + memcpy(&cbq->id.id, id, sizeof(struct cb_id)); + cbq->callback = callback; + return cbq; +} + +void cn_queue_release_callback(struct cn_callback_entry *cbq) +{ + if (!refcount_dec_and_test(&cbq->refcnt)) + return; + + atomic_dec(&cbq->pdev->refcnt); + kfree(cbq); +} + +int cn_cb_equal(const struct cb_id *i1, const struct cb_id *i2) +{ + return ((i1->idx == i2->idx) && (i1->val == i2->val)); +} + +int cn_queue_add_callback(struct cn_queue_dev *dev, const char *name, + const struct cb_id *id, + void (*callback)(struct cn_msg *, + struct netlink_skb_parms *)) +{ + struct cn_callback_entry *cbq, *__cbq; + int found = 0; + + cbq = cn_queue_alloc_callback_entry(dev, name, id, callback); + if (!cbq) + return -ENOMEM; + + spin_lock_bh(&dev->queue_lock); + list_for_each_entry(__cbq, &dev->queue_list, callback_entry) { + if (cn_cb_equal(&__cbq->id.id, id)) { + found = 1; + break; + } + } + if (!found) + list_add_tail(&cbq->callback_entry, &dev->queue_list); + spin_unlock_bh(&dev->queue_lock); + + if (found) { + cn_queue_release_callback(cbq); + return -EINVAL; + } + + cbq->seq = 0; + cbq->group = cbq->id.id.idx; + + return 0; +} + +void cn_queue_del_callback(struct cn_queue_dev *dev, const struct cb_id *id) +{ + struct cn_callback_entry *cbq, *n; + int found = 0; + + spin_lock_bh(&dev->queue_lock); + list_for_each_entry_safe(cbq, n, &dev->queue_list, callback_entry) { + if (cn_cb_equal(&cbq->id.id, id)) { + list_del(&cbq->callback_entry); + found = 1; + break; + } + } + spin_unlock_bh(&dev->queue_lock); + + if (found) + cn_queue_release_callback(cbq); +} + +struct cn_queue_dev *cn_queue_alloc_dev(const char *name, struct sock *nls) +{ + struct cn_queue_dev *dev; + + dev = kzalloc(sizeof(*dev), GFP_KERNEL); + if (!dev) + return NULL; + + snprintf(dev->name, sizeof(dev->name), "%s", name); + atomic_set(&dev->refcnt, 0); + INIT_LIST_HEAD(&dev->queue_list); + spin_lock_init(&dev->queue_lock); + + dev->nls = nls; + + return dev; +} + +void cn_queue_free_dev(struct cn_queue_dev *dev) +{ + struct cn_callback_entry *cbq, *n; + + spin_lock_bh(&dev->queue_lock); + list_for_each_entry_safe(cbq, n, &dev->queue_list, callback_entry) + list_del(&cbq->callback_entry); + spin_unlock_bh(&dev->queue_lock); + + while (atomic_read(&dev->refcnt)) { + pr_info("Waiting for %s to become free: refcnt=%d.\n", + dev->name, atomic_read(&dev->refcnt)); + msleep(1000); + } + + kfree(dev); + dev = NULL; +} |