mirror of
https://github.com/torvalds/linux.git
synced 2024-12-04 10:01:41 +00:00
9decff5f40
kfree() and bitmap_free() are the same. But using the latter is more consistent when freeing memory allocated with bitmap_zalloc(). Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Reviewed-by: Sumit Garg <sumit.garg@linaro.org> Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
126 lines
2.5 KiB
C
126 lines
2.5 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* Copyright (c) 2015-2021, Linaro Limited
|
|
*/
|
|
|
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
|
|
|
#include <linux/arm-smccc.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/tee_drv.h>
|
|
#include "optee_private.h"
|
|
|
|
struct notif_entry {
|
|
struct list_head link;
|
|
struct completion c;
|
|
u_int key;
|
|
};
|
|
|
|
static bool have_key(struct optee *optee, u_int key)
|
|
{
|
|
struct notif_entry *entry;
|
|
|
|
list_for_each_entry(entry, &optee->notif.db, link)
|
|
if (entry->key == key)
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
int optee_notif_wait(struct optee *optee, u_int key)
|
|
{
|
|
unsigned long flags;
|
|
struct notif_entry *entry;
|
|
int rc = 0;
|
|
|
|
if (key > optee->notif.max_key)
|
|
return -EINVAL;
|
|
|
|
entry = kmalloc(sizeof(*entry), GFP_KERNEL);
|
|
if (!entry)
|
|
return -ENOMEM;
|
|
init_completion(&entry->c);
|
|
entry->key = key;
|
|
|
|
spin_lock_irqsave(&optee->notif.lock, flags);
|
|
|
|
/*
|
|
* If the bit is already set it means that the key has already
|
|
* been posted and we must not wait.
|
|
*/
|
|
if (test_bit(key, optee->notif.bitmap)) {
|
|
clear_bit(key, optee->notif.bitmap);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Check if someone is already waiting for this key. If there is
|
|
* it's a programming error.
|
|
*/
|
|
if (have_key(optee, key)) {
|
|
rc = -EBUSY;
|
|
goto out;
|
|
}
|
|
|
|
list_add_tail(&entry->link, &optee->notif.db);
|
|
|
|
/*
|
|
* Unlock temporarily and wait for completion.
|
|
*/
|
|
spin_unlock_irqrestore(&optee->notif.lock, flags);
|
|
wait_for_completion(&entry->c);
|
|
spin_lock_irqsave(&optee->notif.lock, flags);
|
|
|
|
list_del(&entry->link);
|
|
out:
|
|
spin_unlock_irqrestore(&optee->notif.lock, flags);
|
|
|
|
kfree(entry);
|
|
|
|
return rc;
|
|
}
|
|
|
|
int optee_notif_send(struct optee *optee, u_int key)
|
|
{
|
|
unsigned long flags;
|
|
struct notif_entry *entry;
|
|
|
|
if (key > optee->notif.max_key)
|
|
return -EINVAL;
|
|
|
|
spin_lock_irqsave(&optee->notif.lock, flags);
|
|
|
|
list_for_each_entry(entry, &optee->notif.db, link)
|
|
if (entry->key == key) {
|
|
complete(&entry->c);
|
|
goto out;
|
|
}
|
|
|
|
/* Only set the bit in case there where nobody waiting */
|
|
set_bit(key, optee->notif.bitmap);
|
|
out:
|
|
spin_unlock_irqrestore(&optee->notif.lock, flags);
|
|
|
|
return 0;
|
|
}
|
|
|
|
int optee_notif_init(struct optee *optee, u_int max_key)
|
|
{
|
|
spin_lock_init(&optee->notif.lock);
|
|
INIT_LIST_HEAD(&optee->notif.db);
|
|
optee->notif.bitmap = bitmap_zalloc(max_key, GFP_KERNEL);
|
|
if (!optee->notif.bitmap)
|
|
return -ENOMEM;
|
|
|
|
optee->notif.max_key = max_key;
|
|
|
|
return 0;
|
|
}
|
|
|
|
void optee_notif_uninit(struct optee *optee)
|
|
{
|
|
bitmap_free(optee->notif.bitmap);
|
|
}
|