[patch 5/5] spufs use the new vm_ops->access

[Rik van Riel]

spufs: use new vm_ops->access to allow local state access from gdb

This uses the new vm_ops->access to allow gdb to access the SPU
local store. We currently prevent access to problem state registers,
this can be done later if really needed but it's safer not to.

Signed-off-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Rik van Riel <riel@xxxxxxxxxx>
---

Index: ptrace-2.6.26-rc2-mm1/arch/powerpc/platforms/cell/spufs/file.c
===================================================================
--- ptrace-2.6.26-rc2-mm1.orig/arch/powerpc/platforms/cell/spufs/file.c	2008-05-15 13:35:39.000000000 -0400
+++ ptrace-2.6.26-rc2-mm1/arch/powerpc/platforms/cell/spufs/file.c	2008-05-15 13:42:26.000000000 -0400
@@ -287,9 +287,32 @@ spufs_mem_mmap_fault(struct vm_area_stru
 	return VM_FAULT_NOPAGE;
 }
 
+static int spufs_mem_mmep_access(struct vm_area_struct *vma,
+				unsigned long address,
+				void *buf, int len, int write)
+{
+	struct spu_context *ctx = vma->vm_file->private_data;
+	unsigned long offset = address - vma->vm_start;
+	char *local_store;
+
+	if (write && !(vma->vm_flags & VM_WRITE))
+		return -EACCES;
+	if (spu_acquire(ctx))
+		return -EINTR;
+	if ((offset + len) > vma->vm_end)
+		len = vma->vm_end - offset;
+	local_store = ctx->ops->get_ls(ctx);
+	if (write)
+		memcpy_toio(local_store + offset, buf, len);
+	else
+		memcpy_fromio(buf, local_store + offset, len);
+	spu_release(ctx);
+	return len;
+}
 
 static struct vm_operations_struct spufs_mem_mmap_vmops = {
 	.fault = spufs_mem_mmap_fault,
+	.access = spufs_mem_mmep_access,
 };
 
 static int spufs_mem_mmap(struct file *file, struct vm_area_struct *vma)

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