Le 10/06/2019 à 05:08, Nicholas Piggin a écrit :
Radix can use ioremap_page_range for ioremap, after slab is available.
This makes it possible to enable huge ioremap mapping support.
Signed-off-by: Nicholas Piggin <npig...@gmail.com>
---
arch/powerpc/include/asm/book3s/64/radix.h | 3 +++
arch/powerpc/mm/book3s64/pgtable.c | 21 +++++++++++++++++++++
arch/powerpc/mm/book3s64/radix_pgtable.c | 21 +++++++++++++++++++++
arch/powerpc/mm/pgtable_64.c | 2 +-
4 files changed, 46 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/include/asm/book3s/64/radix.h
b/arch/powerpc/include/asm/book3s/64/radix.h
index 574eca33f893..e04a839cb5b9 100644
--- a/arch/powerpc/include/asm/book3s/64/radix.h
+++ b/arch/powerpc/include/asm/book3s/64/radix.h
@@ -266,6 +266,9 @@ extern void radix__vmemmap_remove_mapping(unsigned long
start,
extern int radix__map_kernel_page(unsigned long ea, unsigned long pa,
pgprot_t flags, unsigned int psz);
+extern int radix__ioremap_range(unsigned long ea, phys_addr_t pa,
+ unsigned long size, pgprot_t prot, int nid);
+
'extern' is pointless here, and checkpatch will cry.
static inline unsigned long radix__get_tree_size(void)
{
unsigned long rts_field;
diff --git a/arch/powerpc/mm/book3s64/pgtable.c
b/arch/powerpc/mm/book3s64/pgtable.c
index ff98b663c83e..953850a602f7 100644
--- a/arch/powerpc/mm/book3s64/pgtable.c
+++ b/arch/powerpc/mm/book3s64/pgtable.c
@@ -450,3 +450,24 @@ int pmd_move_must_withdraw(struct spinlock *new_pmd_ptl,
return true;
}
+
+int ioremap_range(unsigned long ea, phys_addr_t pa, unsigned long size,
pgprot_t prot, int nid)
+{
+ unsigned long i;
+
+ if (radix_enabled())
+ return radix__ioremap_range(ea, pa, size, prot, nid);
This function looks pretty similar to the one in the previous patch.
Since radix_enabled() is available and return false for all other
subarches, I think the above could go in the generic ioremap_range(),
you'll only need to move the function declaration in a common file, for
instance asm/io.h
+
+ 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;
+}
diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c
b/arch/powerpc/mm/book3s64/radix_pgtable.c
index c9bcf428dd2b..db993bc1aef3 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -11,6 +11,7 @@
#define pr_fmt(fmt) "radix-mmu: " fmt
+#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/sched/mm.h>
#include <linux/memblock.h>
@@ -1122,3 +1123,23 @@ void radix__ptep_modify_prot_commit(struct
vm_area_struct *vma,
set_pte_at(mm, addr, ptep, pte);
}
+
+int radix__ioremap_range(unsigned long ea, phys_addr_t pa, unsigned long size,
+ pgprot_t prot, int nid)
+{
+ if (likely(slab_is_available())) {
+ int err = ioremap_page_range(ea, ea + size, pa, prot);
+ if (err)
+ unmap_kernel_range(ea, size);
+ return err;
+ } else {
+ unsigned long i;
+
+ for (i = 0; i < size; i += PAGE_SIZE) {
+ int err = map_kernel_page(ea + i, pa + i, prot);
+ if (WARN_ON_ONCE(err)) /* Should clean up */
+ return err;
+ }
Same loop again.
What about not doing a radix specific function and just putting
something like below in the core ioremap_range() function ?
if (likely(slab_is_available()) && radix_enabled()) {
int err = ioremap_page_range(ea, ea + size, pa, prot);
if (err)
unmap_kernel_range(ea, size);
return err;
}
Because I'm pretty sure will more and more use ioremap_page_range().
+ return 0;
+ }
+}
diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c
index 6bd3660388aa..63cd81130643 100644
--- a/arch/powerpc/mm/pgtable_64.c
+++ b/arch/powerpc/mm/pgtable_64.c
@@ -108,7 +108,7 @@ unsigned long ioremap_bot;
unsigned long ioremap_bot = IOREMAP_BASE;
#endif
-static int ioremap_range(unsigned long ea, phys_addr_t pa, unsigned long size, pgprot_t prot, int nid)
+int __weak ioremap_range(unsigned long ea, phys_addr_t pa, unsigned long size,
pgprot_t prot, int nid)
Hum. Weak functions remain in unused in vmlinux unless
CONFIG_LD_DEAD_CODE_DATA_ELIMINATION is selected.
Also, they are some how dangerous because people might change them
without seeing that it is overridden for some particular configuration.
Christophe
{
unsigned long i;
