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// SPDX-License-Identifier: GPL-2.0-or-later
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
int __weak ioremap_range(unsigned long ea, phys_addr_t pa, unsigned long size,
pgprot_t prot, int nid)
{
unsigned long i;
for (i = 0; i < size; i += PAGE_SIZE) {
int err = map_kernel_page(ea + i, pa + i, prot);
if (err) {
if (slab_is_available())
unmap_kernel_range(ea, size);
else
WARN_ON_ONCE(1); /* Should clean up */
return err;
}
}
return 0;
}
/**
* Low level function to establish the page tables for an IO mapping
*/
void __iomem *__ioremap_at(phys_addr_t pa, void *ea, unsigned long size, pgprot_t prot)
{
/* We don't support the 4K PFN hack with ioremap */
if (pgprot_val(prot) & H_PAGE_4K_PFN)
return NULL;
if ((ea + size) >= (void *)IOREMAP_END) {
pr_warn("Outside the supported range\n");
return NULL;
}
WARN_ON(pa & ~PAGE_MASK);
WARN_ON(((unsigned long)ea) & ~PAGE_MASK);
WARN_ON(size & ~PAGE_MASK);
if (ioremap_range((unsigned long)ea, pa, size, prot, NUMA_NO_NODE))
return NULL;
return (void __iomem *)ea;
}
EXPORT_SYMBOL(__ioremap_at);
/**
* Low level function to tear down the page tables for an IO mapping. This is
* used for mappings that are manipulated manually, like partial unmapping of
* PCI IOs or ISA space.
*/
void __iounmap_at(void *ea, unsigned long size)
{
WARN_ON(((unsigned long)ea) & ~PAGE_MASK);
WARN_ON(size & ~PAGE_MASK);
unmap_kernel_range((unsigned long)ea, size);
}
EXPORT_SYMBOL(__iounmap_at);
void __iomem *__ioremap_caller(phys_addr_t addr, unsigned long size,
pgprot_t prot, void *caller)
{
phys_addr_t paligned;
void __iomem *ret;
/*
* 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;
size = PAGE_ALIGN(addr + size) - paligned;
if (size == 0 || paligned == 0)
return NULL;
if (slab_is_available()) {
struct vm_struct *area;
area = __get_vm_area_caller(size, VM_IOREMAP, ioremap_bot,
IOREMAP_END, caller);
if (area == NULL)
return NULL;
area->phys_addr = paligned;
ret = __ioremap_at(paligned, area->addr, size, prot);
} else {
ret = __ioremap_at(paligned, (void *)ioremap_bot, size, prot);
if (ret)
ioremap_bot += size;
}
if (ret)
ret += addr & ~PAGE_MASK;
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)
{
void *addr;
if (!slab_is_available())
return;
addr = (void *)((unsigned long __force)PCI_FIX_ADDR(token) & PAGE_MASK);
if ((unsigned long)addr < ioremap_bot) {
pr_warn("Attempt to iounmap early bolted mapping at 0x%p\n", addr);
return;
}
vunmap(addr);
}
EXPORT_SYMBOL(iounmap);
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