rust/helpers.c

// SPDX-License-Identifier: GPL-2.0

#include <linux/bug.h>
#include <linux/build_bug.h>
#include <linux/uaccess.h>
#include <linux/sched/signal.h>
#include <linux/gfp.h>
#include <linux/highmem.h>
#include <linux/uio.h>
#include <linux/errname.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/security.h>
#include <asm/io.h>

__noreturn void rust_helper_BUG(void)
{
	BUG();
}

unsigned long rust_helper_copy_from_user(void *to, const void __user *from, unsigned long n)
{
	return copy_from_user(to, from, n);
}

unsigned long rust_helper_copy_to_user(void __user *to, const void *from, unsigned long n)
{
	return copy_to_user(to, from, n);
}

unsigned long rust_helper_clear_user(void __user *to, unsigned long n)
{
	return clear_user(to, n);
}

void __iomem *rust_helper_ioremap(resource_size_t offset, unsigned long size)
{
	return ioremap(offset, size);
}
EXPORT_SYMBOL_GPL(rust_helper_ioremap);

u8 rust_helper_readb(const volatile void __iomem *addr)
{
        return readb(addr);
}
EXPORT_SYMBOL_GPL(rust_helper_readb);

u16 rust_helper_readw(const volatile void __iomem *addr)
{
        return readw(addr);
}
EXPORT_SYMBOL_GPL(rust_helper_readw);

u32 rust_helper_readl(const volatile void __iomem *addr)
{
        return readl(addr);
}
EXPORT_SYMBOL_GPL(rust_helper_readl);

#ifdef CONFIG_64BIT
u64 rust_helper_readq(const volatile void __iomem *addr)
{
        return readq(addr);
}
EXPORT_SYMBOL_GPL(rust_helper_readq);
#endif

void rust_helper_writeb(u8 value, volatile void __iomem *addr)
{
        writeb(value, addr);
}
EXPORT_SYMBOL_GPL(rust_helper_writeb);

void rust_helper_writew(u16 value, volatile void __iomem *addr)
{
        writew(value, addr);
}
EXPORT_SYMBOL_GPL(rust_helper_writew);

void rust_helper_writel(u32 value, volatile void __iomem *addr)
{
        writel(value, addr);
}
EXPORT_SYMBOL_GPL(rust_helper_writel);

#ifdef CONFIG_64BIT
void rust_helper_writeq(u64 value, volatile void __iomem *addr)
{
        writeq(value, addr);
}
EXPORT_SYMBOL_GPL(rust_helper_writeq);
#endif

void rust_helper___spin_lock_init(spinlock_t *lock, const char *name,
				  struct lock_class_key *key)
{
#ifdef CONFIG_DEBUG_SPINLOCK
	__spin_lock_init(lock, name, key);
#else
	spin_lock_init(lock);
#endif
}
EXPORT_SYMBOL_GPL(rust_helper___spin_lock_init);

void rust_helper_spin_lock(spinlock_t *lock)
{
	spin_lock(lock);
}
EXPORT_SYMBOL_GPL(rust_helper_spin_lock);

void rust_helper_spin_unlock(spinlock_t *lock)
{
	spin_unlock(lock);
}
EXPORT_SYMBOL_GPL(rust_helper_spin_unlock);

void rust_helper_init_wait(struct wait_queue_entry *wq_entry)
{
	init_wait(wq_entry);
}
EXPORT_SYMBOL_GPL(rust_helper_init_wait);

int rust_helper_signal_pending(struct task_struct *t)
{
	return signal_pending(t);
}
EXPORT_SYMBOL_GPL(rust_helper_signal_pending);

struct page *rust_helper_alloc_pages(gfp_t gfp_mask, unsigned int order)
{
	return alloc_pages(gfp_mask, order);
}
EXPORT_SYMBOL_GPL(rust_helper_alloc_pages);

void *rust_helper_kmap(struct page *page)
{
	return kmap(page);
}
EXPORT_SYMBOL_GPL(rust_helper_kmap);

void rust_helper_kunmap(struct page *page)
{
	return kunmap(page);
}
EXPORT_SYMBOL_GPL(rust_helper_kunmap);

int rust_helper_cond_resched(void)
{
	return cond_resched();
}
EXPORT_SYMBOL_GPL(rust_helper_cond_resched);

size_t rust_helper_copy_from_iter(void *addr, size_t bytes, struct iov_iter *i)
{
	return copy_from_iter(addr, bytes, i);
}
EXPORT_SYMBOL_GPL(rust_helper_copy_from_iter);

size_t rust_helper_copy_to_iter(const void *addr, size_t bytes, struct iov_iter *i)
{
	return copy_to_iter(addr, bytes, i);
}
EXPORT_SYMBOL_GPL(rust_helper_copy_to_iter);

bool rust_helper_IS_ERR(__force const void *ptr)
{
	return IS_ERR(ptr);
}
EXPORT_SYMBOL_GPL(rust_helper_IS_ERR);

long rust_helper_PTR_ERR(__force const void *ptr)
{
	return PTR_ERR(ptr);
}
EXPORT_SYMBOL_GPL(rust_helper_PTR_ERR);

const char *rust_helper_errname(int err)
{
	return errname(err);
}
EXPORT_SYMBOL_GPL(rust_helper_errname);

void rust_helper_mutex_lock(struct mutex *lock)
{
	mutex_lock(lock);
}
EXPORT_SYMBOL_GPL(rust_helper_mutex_lock);

void *
rust_helper_platform_get_drvdata(const struct platform_device *pdev)
{
	return platform_get_drvdata(pdev);
}
EXPORT_SYMBOL_GPL(rust_helper_platform_get_drvdata);

void
rust_helper_platform_set_drvdata(struct platform_device *pdev,
				 void *data)
{
	return platform_set_drvdata(pdev, data);
}
EXPORT_SYMBOL_GPL(rust_helper_platform_set_drvdata);

refcount_t rust_helper_REFCOUNT_INIT(int n)
{
	return (refcount_t)REFCOUNT_INIT(n);
}
EXPORT_SYMBOL_GPL(rust_helper_REFCOUNT_INIT);

void rust_helper_refcount_inc(refcount_t *r)
{
	refcount_inc(r);
}
EXPORT_SYMBOL_GPL(rust_helper_refcount_inc);

bool rust_helper_refcount_dec_and_test(refcount_t *r)
{
	return refcount_dec_and_test(r);
}
EXPORT_SYMBOL_GPL(rust_helper_refcount_dec_and_test);

void rust_helper_rb_link_node(struct rb_node *node, struct rb_node *parent,
			      struct rb_node **rb_link)
{
	rb_link_node(node, parent, rb_link);
}
EXPORT_SYMBOL_GPL(rust_helper_rb_link_node);

struct task_struct *rust_helper_get_current(void)
{
	return current;
}
EXPORT_SYMBOL_GPL(rust_helper_get_current);

void rust_helper_get_task_struct(struct task_struct * t)
{
	get_task_struct(t);
}
EXPORT_SYMBOL_GPL(rust_helper_get_task_struct);

void rust_helper_put_task_struct(struct task_struct * t)
{
	put_task_struct(t);
}
EXPORT_SYMBOL_GPL(rust_helper_put_task_struct);

int rust_helper_security_binder_set_context_mgr(struct task_struct *mgr)
{
	return security_binder_set_context_mgr(mgr);
}
EXPORT_SYMBOL_GPL(rust_helper_security_binder_set_context_mgr);

int rust_helper_security_binder_transaction(struct task_struct *from,
					    struct task_struct *to)
{
	return security_binder_transaction(from, to);
}
EXPORT_SYMBOL_GPL(rust_helper_security_binder_transaction);

int rust_helper_security_binder_transfer_binder(struct task_struct *from,
						struct task_struct *to)
{
	return security_binder_transfer_binder(from, to);
}
EXPORT_SYMBOL_GPL(rust_helper_security_binder_transfer_binder);

int rust_helper_security_binder_transfer_file(struct task_struct *from,
					      struct task_struct *to,
					      struct file *file)
{
	return security_binder_transfer_file(from, to, file);
}
EXPORT_SYMBOL_GPL(rust_helper_security_binder_transfer_file);

void *rust_helper_dev_get_drvdata(struct device *dev)
{
	return dev_get_drvdata(dev);
}
EXPORT_SYMBOL_GPL(rust_helper_dev_get_drvdata);

/* We use bindgen's --size_t-is-usize option to bind the C size_t type
 * as the Rust usize type, so we can use it in contexts where Rust
 * expects a usize like slice (array) indices. usize is defined to be
 * the same as C's uintptr_t type (can hold any pointer) but not
 * necessarily the same as size_t (can hold the size of any single
 * object). Most modern platforms use the same concrete integer type for
 * both of them, but in case we find ourselves on a platform where
 * that's not true, fail early instead of risking ABI or
 * integer-overflow issues.
 *
 * If your platform fails this assertion, it means that you are in
 * danger of integer-overflow bugs (even if you attempt to remove
 * --size_t-is-usize). It may be easiest to change the kernel ABI on
 * your platform such that size_t matches uintptr_t (i.e., to increase
 * size_t, because uintptr_t has to be at least as big as size_t).
*/
static_assert(
	sizeof(size_t) == sizeof(uintptr_t) &&
	__alignof__(size_t) == __alignof__(uintptr_t),
	"Rust code expects C size_t to match Rust usize"
);