[POWERPC] Fix spu SLB invalidations

The SPU code doesn't properly invalidate SPUs SLBs when necessary,
for example when changing a segment size from the hugetlbfs code. In
addition, it saves and restores the SLB content on context switches
which makes it harder to properly handle those invalidations.

This patch removes the saving & restoring for now, something more
efficient might be found later on. It also adds a spu_flush_all_slbs(mm)
that can be used by the core mm code to flush the SLBs of all SPEs that
are running a given mm at the time of the flush.

In order to do that, it adds a spinlock to the list of all SPEs and move
some bits & pieces from spufs to spu_base.c

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

2 files changed, 7 insertions, 4 deletions

diff --git a/include/asm-powerpc/spu.h b/include/asm-powerpc/spu.h
index 0f9f2dd24a79..31d5054be20f 100644
--- a/include/asm-powerpc/spu.h
+++ b/include/asm-powerpc/spu.h
@@ -165,6 +165,13 @@ int spu_irq_class_0_bottom(struct spu *spu);
 int spu_irq_class_1_bottom(struct spu *spu);
 void spu_irq_setaffinity(struct spu *spu, int cpu);
 
+extern void spu_invalidate_slbs(struct spu *spu);
+extern void spu_associate_mm(struct spu *spu, struct mm_struct *mm);
+
+/* Calls from the memory management to the SPU */
+struct mm_struct;
+extern void spu_flush_all_slbs(struct mm_struct *mm);
+
 /* system callbacks from the SPU */
 struct spu_syscall_block {
         u64 nr_ret;
diff --git a/include/asm-powerpc/spu_csa.h b/include/asm-powerpc/spu_csa.h
index bdbf906a767f..8aad0619eb8e 100644
--- a/include/asm-powerpc/spu_csa.h
+++ b/include/asm-powerpc/spu_csa.h
@@ -221,8 +221,6 @@ struct spu_priv2_collapsed {
  * @spu_chnlcnt_RW: Array of saved channel counts.
  * @spu_chnldata_RW: Array of saved channel data.
  * @suspend_time: Time stamp when decrementer disabled.
- * @slb_esid_RW: Array of saved SLB esid entries.
- * @slb_vsid_RW: Array of saved SLB vsid entries.
  *
  * Structure representing the whole of the SPU
  * context save area (CSA).  This struct contains
@@ -245,8 +243,6 @@ struct spu_state {
         u32 spu_mailbox_data[4];
         u32 pu_mailbox_data[1];
         unsigned long suspend_time;
-        u64 slb_esid_RW[8];
-        u64 slb_vsid_RW[8];
         spinlock_t register_lock;
 };