[PATCH v2 3/9] powerpc/mem: Remove address argument to flush_coherent_icache()

From: Christophe Leroy
Date: Thu Apr 08 2021 - 11:30:57 EST


flush_coherent_icache() can use any valid address as mentionned
by the comment.

Use PAGE_OFFSET as base address. This allows removing the
user access stuff.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
---
arch/powerpc/mm/cacheflush.c | 13 +++++--------
1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/mm/cacheflush.c b/arch/powerpc/mm/cacheflush.c
index 742d3e0fb12f..dc2d39da6f63 100644
--- a/arch/powerpc/mm/cacheflush.c
+++ b/arch/powerpc/mm/cacheflush.c
@@ -5,10 +5,9 @@

/**
* flush_coherent_icache() - if a CPU has a coherent icache, flush it
- * @addr: The base address to use (can be any valid address, the whole cache will be flushed)
* Return true if the cache was flushed, false otherwise
*/
-static inline bool flush_coherent_icache(unsigned long addr)
+static inline bool flush_coherent_icache(void)
{
/*
* For a snooping icache, we still need a dummy icbi to purge all the
@@ -18,9 +17,7 @@ static inline bool flush_coherent_icache(unsigned long addr)
*/
if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) {
mb(); /* sync */
- allow_read_from_user((const void __user *)addr, L1_CACHE_BYTES);
- icbi((void *)addr);
- prevent_read_from_user((const void __user *)addr, L1_CACHE_BYTES);
+ icbi((void *)PAGE_OFFSET);
mb(); /* sync */
isync();
return true;
@@ -60,7 +57,7 @@ static void invalidate_icache_range(unsigned long start, unsigned long stop)
*/
void flush_icache_range(unsigned long start, unsigned long stop)
{
- if (flush_coherent_icache(start))
+ if (flush_coherent_icache())
return;

clean_dcache_range(start, stop);
@@ -146,7 +143,7 @@ static void __flush_dcache_icache(void *p)
{
unsigned long addr = (unsigned long)p;

- if (flush_coherent_icache(addr))
+ if (flush_coherent_icache())
return;

clean_dcache_range(addr, addr + PAGE_SIZE);
@@ -200,7 +197,7 @@ void flush_dcache_icache_page(struct page *page)
} else {
unsigned long addr = page_to_pfn(page) << PAGE_SHIFT;

- if (flush_coherent_icache(addr))
+ if (flush_coherent_icache())
return;
flush_dcache_icache_phys(addr);
}
--
2.25.0