[POWERPC] spufs: fix context destruction during psmap fault

[linux-2.6-omap-h63xx.git] / arch / powerpc / platforms / cell / spufs / file.c

diff --git a/arch/powerpc/platforms/cell/spufs/file.c b/arch/powerpc/platforms/cell/spufs/file.c
index c66c3756970d53d52ae56df931e38219a9e79ade..f7a7e8635fb6f98d11ab8aa5bf5cf3d2d6f49bf8 100644 (file)
--- a/arch/powerpc/platforms/cell/spufs/file.c
+++ b/arch/powerpc/platforms/cell/spufs/file.c
@@ -366,6 +366,13 @@ static unsigned long spufs_ps_nopfn(struct vm_area_struct *vma,
        if (offset >= ps_size)
                return NOPFN_SIGBUS;
 
+       /*
+        * Because we release the mmap_sem, the context may be destroyed while
+        * we're in spu_wait. Grab an extra reference so it isn't destroyed
+        * in the meantime.
+        */
+       get_spu_context(ctx);
+
        /*
         * We have to wait for context to be loaded before we have
         * pages to hand out to the user, but we don't want to wait
@@ -375,7 +382,7 @@ static unsigned long spufs_ps_nopfn(struct vm_area_struct *vma,
         * hanged.
         */
        if (spu_acquire(ctx))
-               return NOPFN_REFAULT;
+               goto refault;
 
        if (ctx->state == SPU_STATE_SAVED) {
                up_read(&current->mm->mmap_sem);
@@ -391,6 +398,9 @@ static unsigned long spufs_ps_nopfn(struct vm_area_struct *vma,
 
        if (!ret)
                spu_release(ctx);
+
+refault:
+       put_spu_context(ctx);
        return NOPFN_REFAULT;
 }