mirror of
https://github.com/torvalds/linux
synced 2024-10-03 09:48:02 +00:00
0439fcff30
Since commit 25559c22ce ("tee: add kernel internal client interface"),
it has been a common include/linux/tee_drv.h header file which is shared
to hold TEE subsystem internal bits along with the APIs exposed to the
TEE client drivers. However, this practice is prone to TEE subsystem
internal APIs abuse and especially so with the new TEE implementation
drivers being added to reuse existing functionality.
In order to address this split TEE subsystem internal bits as a separate
header file: include/linux/tee_core.h which should be the one used by
TEE implementation drivers. With that include/linux/tee_drv.h lists only
APIs exposed by TEE subsystem to the TEE client drivers.
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Signed-off-by: Balint Dobszay <balint.dobszay@arm.com>
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
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/*
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* Copyright (c) 2015-2021, Linaro Limited
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/arm-smccc.h>
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#include <linux/errno.h>
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include <linux/tee_core.h>
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#include "optee_private.h"
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struct notif_entry {
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struct list_head link;
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struct completion c;
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u_int key;
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};
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static bool have_key(struct optee *optee, u_int key)
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{
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struct notif_entry *entry;
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list_for_each_entry(entry, &optee->notif.db, link)
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if (entry->key == key)
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return true;
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return false;
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}
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int optee_notif_wait(struct optee *optee, u_int key)
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{
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unsigned long flags;
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struct notif_entry *entry;
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int rc = 0;
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if (key > optee->notif.max_key)
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return -EINVAL;
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entry = kmalloc(sizeof(*entry), GFP_KERNEL);
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if (!entry)
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return -ENOMEM;
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init_completion(&entry->c);
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entry->key = key;
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spin_lock_irqsave(&optee->notif.lock, flags);
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/*
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* If the bit is already set it means that the key has already
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* been posted and we must not wait.
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*/
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if (test_bit(key, optee->notif.bitmap)) {
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clear_bit(key, optee->notif.bitmap);
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goto out;
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}
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/*
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* Check if someone is already waiting for this key. If there is
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* it's a programming error.
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*/
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if (have_key(optee, key)) {
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rc = -EBUSY;
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goto out;
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}
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list_add_tail(&entry->link, &optee->notif.db);
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/*
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* Unlock temporarily and wait for completion.
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*/
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spin_unlock_irqrestore(&optee->notif.lock, flags);
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wait_for_completion(&entry->c);
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spin_lock_irqsave(&optee->notif.lock, flags);
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list_del(&entry->link);
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out:
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spin_unlock_irqrestore(&optee->notif.lock, flags);
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kfree(entry);
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return rc;
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}
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int optee_notif_send(struct optee *optee, u_int key)
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{
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unsigned long flags;
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struct notif_entry *entry;
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if (key > optee->notif.max_key)
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return -EINVAL;
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spin_lock_irqsave(&optee->notif.lock, flags);
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list_for_each_entry(entry, &optee->notif.db, link)
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if (entry->key == key) {
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complete(&entry->c);
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goto out;
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}
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/* Only set the bit in case there where nobody waiting */
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set_bit(key, optee->notif.bitmap);
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out:
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spin_unlock_irqrestore(&optee->notif.lock, flags);
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return 0;
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}
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int optee_notif_init(struct optee *optee, u_int max_key)
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{
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spin_lock_init(&optee->notif.lock);
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INIT_LIST_HEAD(&optee->notif.db);
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optee->notif.bitmap = bitmap_zalloc(max_key, GFP_KERNEL);
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if (!optee->notif.bitmap)
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return -ENOMEM;
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optee->notif.max_key = max_key;
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return 0;
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}
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void optee_notif_uninit(struct optee *optee)
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{
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bitmap_free(optee->notif.bitmap);
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}
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