// SPDX-License-Identifier: GPL-2.0-or-later

#include <linux/io.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>

void __iomem *__ioremap_caller(phys_addr_t addr, unsigned long size,
                               pgprot_t prot, void *caller)
{
        phys_addr_t paligned, offset;
        void __iomem *ret;
        int err;

        /* We don't support the 4K PFN hack with ioremap */
        if (pgprot_val(prot) & H_PAGE_4K_PFN)
                return NULL;

        /*
         * Choose an address to map it to. Once the vmalloc system is running,
         * we use it. Before that, we map using addresses going up from
         * ioremap_bot.  vmalloc will use the addresses from IOREMAP_BASE
         * through ioremap_bot.
         */
        paligned = addr & PAGE_MASK;
        offset = addr & ~PAGE_MASK;
        size = PAGE_ALIGN(addr + size) - paligned;

        if (size == 0 || paligned == 0)
                return NULL;

        if (slab_is_available())
                return generic_ioremap_prot(addr, size, prot);

        pr_warn("ioremap() called early from %pS. Use early_ioremap() instead\n", caller);

        err = early_ioremap_range(ioremap_bot, paligned, size, prot);
        if (err)
                return NULL;

        ret = (void __iomem *)ioremap_bot + offset;
        ioremap_bot += size + PAGE_SIZE;

        return ret;
}

/*
 * Unmap an IO region and remove it from vmalloc'd list.
 * Access to IO memory should be serialized by driver.
 */
void iounmap(volatile void __iomem *token)
{
        if (!slab_is_available())
                return;

        generic_iounmap(token);
}
EXPORT_SYMBOL(iounmap);