MIPS: c-r4k: Split user/kernel flush_icache_range()

flush_icache_range() is used for both user addresses (i.e.
cacheflush(2)), and kernel addresses (as the API documentation
describes).

This isn't really suitable however for Enhanced Virtual Addressing (EVA)
where cache operations on usermode addresses must use a different
instruction, and the protected cache ops assume user addresses, making
flush_icache_range() ineffective on kernel addresses.

Split out a new __flush_icache_user_range() and
__local_flush_icache_user_range() for users which actually want to flush
usermode addresses (note that flush_icache_user_range() already exists
on various architectures but with different arguments).

The implementation of flush_icache_range() will be changed in an
upcoming commit to use unprotected normal cache ops so as to always work
on the kernel mode address space.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Leonid Yegoshin <leonid.yegoshin@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14152/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --git a/arch/mips/include/asm/cacheflush.h b/arch/mips/include/asm/cacheflush.h
index 34ed22e..4812d1f 100644 (file)
--- a/arch/mips/include/asm/cacheflush.h
+++ b/arch/mips/include/asm/cacheflush.h
@@ -28,6 +28,7 @@
  *  - flush_cache_sigtramp() flush signal trampoline
  *  - flush_icache_all() flush the entire instruction cache
  *  - flush_data_cache_page() flushes a page from the data cache
+ *  - __flush_icache_user_range(start, end) flushes range of user instructions
  */
 
  /*
@@ -80,6 +81,10 @@ static inline void flush_icache_page(struct vm_area_struct *vma,
 
 extern void (*flush_icache_range)(unsigned long start, unsigned long end);
 extern void (*local_flush_icache_range)(unsigned long start, unsigned long end);
+extern void (*__flush_icache_user_range)(unsigned long start,
+                                        unsigned long end);
+extern void (*__local_flush_icache_user_range)(unsigned long start,
+                                              unsigned long end);
 
 extern void (*__flush_cache_vmap)(void);
 

diff --git a/arch/mips/mm/c-octeon.c b/arch/mips/mm/c-octeon.c
index 05b1d7c..0e45b06 100644 (file)
--- a/arch/mips/mm/c-octeon.c
+++ b/arch/mips/mm/c-octeon.c
@@ -294,6 +294,8 @@ void octeon_cache_init(void)
        flush_data_cache_page           = octeon_flush_data_cache_page;
        flush_icache_range              = octeon_flush_icache_range;
        local_flush_icache_range        = local_octeon_flush_icache_range;
+       __flush_icache_user_range       = octeon_flush_icache_range;
+       __local_flush_icache_user_range = local_octeon_flush_icache_range;
 
        __flush_kernel_vmap_range       = octeon_flush_kernel_vmap_range;
 

diff --git a/arch/mips/mm/c-r3k.c b/arch/mips/mm/c-r3k.c
index 135ec31..21e4e66 100644 (file)
--- a/arch/mips/mm/c-r3k.c
+++ b/arch/mips/mm/c-r3k.c
@@ -325,6 +325,8 @@ void r3k_cache_init(void)
        flush_cache_page = r3k_flush_cache_page;
        flush_icache_range = r3k_flush_icache_range;
        local_flush_icache_range = r3k_flush_icache_range;
+       __flush_icache_user_range = r3k_flush_icache_range;
+       __local_flush_icache_user_range = r3k_flush_icache_range;
 
        __flush_kernel_vmap_range = r3k_flush_kernel_vmap_range;
 

diff --git a/arch/mips/mm/c-r4k.c b/arch/mips/mm/c-r4k.c
index bbb7dfe..5e0a44a 100644 (file)
--- a/arch/mips/mm/c-r4k.c
+++ b/arch/mips/mm/c-r4k.c
@@ -1904,6 +1904,8 @@ void r4k_cache_init(void)
        flush_data_cache_page   = r4k_flush_data_cache_page;
        flush_icache_range      = r4k_flush_icache_range;
        local_flush_icache_range        = local_r4k_flush_icache_range;
+       __flush_icache_user_range       = r4k_flush_icache_range;
+       __local_flush_icache_user_range = local_r4k_flush_icache_range;
 
 #if defined(CONFIG_DMA_NONCOHERENT) || defined(CONFIG_DMA_MAYBE_COHERENT)
        if (coherentio) {

diff --git a/arch/mips/mm/c-tx39.c b/arch/mips/mm/c-tx39.c
index 596e184..5c28258 100644 (file)
--- a/arch/mips/mm/c-tx39.c
+++ b/arch/mips/mm/c-tx39.c
@@ -411,6 +411,9 @@ void tx39_cache_init(void)
                break;
        }
 
+       __flush_icache_user_range = flush_icache_range;
+       __local_flush_icache_user_range = local_flush_icache_range;
+
        current_cpu_data.icache.waysize = icache_size / current_cpu_data.icache.ways;
        current_cpu_data.dcache.waysize = dcache_size / current_cpu_data.dcache.ways;
 

diff --git a/arch/mips/mm/cache.c b/arch/mips/mm/cache.c
index bf04c6c..5a644c3 100644 (file)
--- a/arch/mips/mm/cache.c
+++ b/arch/mips/mm/cache.c
@@ -33,6 +33,10 @@ void (*flush_icache_range)(unsigned long start, unsigned long end);
 EXPORT_SYMBOL_GPL(flush_icache_range);
 void (*local_flush_icache_range)(unsigned long start, unsigned long end);
 EXPORT_SYMBOL_GPL(local_flush_icache_range);
+void (*__flush_icache_user_range)(unsigned long start, unsigned long end);
+EXPORT_SYMBOL_GPL(__flush_icache_user_range);
+void (*__local_flush_icache_user_range)(unsigned long start, unsigned long end);
+EXPORT_SYMBOL_GPL(__local_flush_icache_user_range);
 
 void (*__flush_cache_vmap)(void);
 void (*__flush_cache_vunmap)(void);