linux/arch/powerpc/mm/ioremap_64.c
Christophe Leroy d538aadc27 powerpc/ioremap: warn on early use of ioremap()
Powerpc now has EARLY_IOREMAP.

Next step is to convert all early users of ioremap() to
early_ioremap().

Add a warning to help locate those users.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b4f03a68ee8e68773c8973d74ec35f9c82c72871.1568295907.git.christophe.leroy@c-s.fr
2019-11-19 19:38:38 +11:00

116 lines
2.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
/**
* 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)
{
int ret;
unsigned long va = (unsigned long)ea;
/* 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 (slab_is_available()) {
ret = ioremap_page_range(va, va + size, pa, prot);
if (ret)
unmap_kernel_range(va, size);
} else {
ret = early_ioremap_range(va, pa, size, prot);
}
if (ret)
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, 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 do_ioremap(paligned, offset, size, prot, caller);
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;
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);