313a5257b8
Since v5.8-rc1 OpenRISC Linux fails to boot when DEBUG_VM is enabled. This has been bisected to commit42fc541404("mmap locking API: add mmap_assert_locked() and mmap_assert_write_locked()"). The added locking checks exposed the issue that OpenRISC was not taking this mmap lock when during page walks for DMA operations. This patch locks and unlocks the mmap lock for page walking. Link: http://lkml.kernel.org/r/20200617090247.1680188-1-shorne@gmail.com Fixes:42fc541404("mmap locking API: add mmap_assert_locked() and mmap_assert_write_locked()" Signed-off-by: Stafford Horne <shorne@gmail.com> Reviewed-by: Michel Lespinasse <walken@google.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Steven Price <steven.price@arm.com> Cc: Thomas Hellstrom <thellstrom@vmware.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Daniel Jordan <daniel.m.jordan@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
126 lines
3.0 KiB
C
126 lines
3.0 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* OpenRISC Linux
|
|
*
|
|
* Linux architectural port borrowing liberally from similar works of
|
|
* others. All original copyrights apply as per the original source
|
|
* declaration.
|
|
*
|
|
* Modifications for the OpenRISC architecture:
|
|
* Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
|
|
* Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
|
|
*
|
|
* DMA mapping callbacks...
|
|
*/
|
|
|
|
#include <linux/dma-noncoherent.h>
|
|
#include <linux/pagewalk.h>
|
|
|
|
#include <asm/cpuinfo.h>
|
|
#include <asm/spr_defs.h>
|
|
#include <asm/tlbflush.h>
|
|
|
|
static int
|
|
page_set_nocache(pte_t *pte, unsigned long addr,
|
|
unsigned long next, struct mm_walk *walk)
|
|
{
|
|
unsigned long cl;
|
|
struct cpuinfo_or1k *cpuinfo = &cpuinfo_or1k[smp_processor_id()];
|
|
|
|
pte_val(*pte) |= _PAGE_CI;
|
|
|
|
/*
|
|
* Flush the page out of the TLB so that the new page flags get
|
|
* picked up next time there's an access
|
|
*/
|
|
flush_tlb_page(NULL, addr);
|
|
|
|
/* Flush page out of dcache */
|
|
for (cl = __pa(addr); cl < __pa(next); cl += cpuinfo->dcache_block_size)
|
|
mtspr(SPR_DCBFR, cl);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct mm_walk_ops set_nocache_walk_ops = {
|
|
.pte_entry = page_set_nocache,
|
|
};
|
|
|
|
static int
|
|
page_clear_nocache(pte_t *pte, unsigned long addr,
|
|
unsigned long next, struct mm_walk *walk)
|
|
{
|
|
pte_val(*pte) &= ~_PAGE_CI;
|
|
|
|
/*
|
|
* Flush the page out of the TLB so that the new page flags get
|
|
* picked up next time there's an access
|
|
*/
|
|
flush_tlb_page(NULL, addr);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct mm_walk_ops clear_nocache_walk_ops = {
|
|
.pte_entry = page_clear_nocache,
|
|
};
|
|
|
|
void *arch_dma_set_uncached(void *cpu_addr, size_t size)
|
|
{
|
|
unsigned long va = (unsigned long)cpu_addr;
|
|
int error;
|
|
|
|
/*
|
|
* We need to iterate through the pages, clearing the dcache for
|
|
* them and setting the cache-inhibit bit.
|
|
*/
|
|
mmap_read_lock(&init_mm);
|
|
error = walk_page_range(&init_mm, va, va + size, &set_nocache_walk_ops,
|
|
NULL);
|
|
mmap_read_unlock(&init_mm);
|
|
|
|
if (error)
|
|
return ERR_PTR(error);
|
|
return cpu_addr;
|
|
}
|
|
|
|
void arch_dma_clear_uncached(void *cpu_addr, size_t size)
|
|
{
|
|
unsigned long va = (unsigned long)cpu_addr;
|
|
|
|
mmap_read_lock(&init_mm);
|
|
/* walk_page_range shouldn't be able to fail here */
|
|
WARN_ON(walk_page_range(&init_mm, va, va + size,
|
|
&clear_nocache_walk_ops, NULL));
|
|
mmap_read_unlock(&init_mm);
|
|
}
|
|
|
|
void arch_sync_dma_for_device(phys_addr_t addr, size_t size,
|
|
enum dma_data_direction dir)
|
|
{
|
|
unsigned long cl;
|
|
struct cpuinfo_or1k *cpuinfo = &cpuinfo_or1k[smp_processor_id()];
|
|
|
|
switch (dir) {
|
|
case DMA_TO_DEVICE:
|
|
/* Flush the dcache for the requested range */
|
|
for (cl = addr; cl < addr + size;
|
|
cl += cpuinfo->dcache_block_size)
|
|
mtspr(SPR_DCBFR, cl);
|
|
break;
|
|
case DMA_FROM_DEVICE:
|
|
/* Invalidate the dcache for the requested range */
|
|
for (cl = addr; cl < addr + size;
|
|
cl += cpuinfo->dcache_block_size)
|
|
mtspr(SPR_DCBIR, cl);
|
|
break;
|
|
default:
|
|
/*
|
|
* NOTE: If dir == DMA_BIDIRECTIONAL then there's no need to
|
|
* flush nor invalidate the cache here as the area will need
|
|
* to be manually synced anyway.
|
|
*/
|
|
break;
|
|
}
|
|
}
|