[POWERPC] Spufs support for 64K LS mappings on 4K kernels

This adds an option to spufs when the kernel is configured for
4K page to give it the ability to use 64K pages for SPE local store
mappings.

Currently, we are optimistic and try order 4 allocations when creating
contexts. If that fails, the code will fallback to 4K automatically.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 9 insertions, 1 deletions

diff --git a/include/asm-powerpc/spu_csa.h b/include/asm-powerpc/spu_csa.h
index 02e56a6685a2..c48ae185c874 100644
--- a/include/asm-powerpc/spu_csa.h
+++ b/include/asm-powerpc/spu_csa.h
@@ -235,6 +235,12 @@ struct spu_priv2_collapsed {
  */
 struct spu_state {
         struct spu_lscsa *lscsa;
+#ifdef CONFIG_SPU_FS_64K_LS
+        int             use_big_pages;
+        /* One struct page per 64k page */
+#define SPU_LSCSA_NUM_BIG_PAGES (sizeof(struct spu_lscsa) / 0x10000)
+        struct page     *lscsa_pages[SPU_LSCSA_NUM_BIG_PAGES];
+#endif
         struct spu_problem_collapsed prob;
         struct spu_priv1_collapsed priv1;
         struct spu_priv2_collapsed priv2;
@@ -247,12 +253,14 @@ struct spu_state {
         spinlock_t register_lock;
 };
 
-extern void spu_init_csa(struct spu_state *csa);
+extern int spu_init_csa(struct spu_state *csa);
 extern void spu_fini_csa(struct spu_state *csa);
 extern int spu_save(struct spu_state *prev, struct spu *spu);
 extern int spu_restore(struct spu_state *new, struct spu *spu);
 extern int spu_switch(struct spu_state *prev, struct spu_state *new,
                       struct spu *spu);
+extern int spu_alloc_lscsa(struct spu_state *csa);
+extern void spu_free_lscsa(struct spu_state *csa);
 
 #endif /* !__SPU__ */
 #endif /* __KERNEL__ */