[PATCH] spufs: enable SPE problem state MMIO access.
This patch is layered on top of CONFIG_SPARSEMEM
and is patterned after direct mapping of LS.
This patch allows mmap() of the following regions:
"mfc", which represents the area from [0x3000 - 0x3fff];
"cntl", which represents the area from [0x4000 - 0x4fff];
"signal1" which begins at offset 0x14000; "signal2" which
begins at offset 0x1c000.
The signal1 & signal2 files may be mmap()'d by regular user
processes. The cntl and mfc file, on the other hand, may
only be accessed if the owning process has CAP_SYS_RAWIO,
because they have the potential to confuse the kernel
with regard to parallel access to the same files with
regular file operations: the kernel always holds a spinlock
when accessing registers in these areas to serialize them,
which can not be guaranteed with user mmaps,
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/platforms/cell/spufs/spufs.h b/arch/powerpc/platforms/cell/spufs/spufs.h
index 57d687c..4485738 100644
--- a/arch/powerpc/platforms/cell/spufs/spufs.h
+++ b/arch/powerpc/platforms/cell/spufs/spufs.h
@@ -43,7 +43,11 @@
struct spu *spu; /* pointer to a physical SPU */
struct spu_state csa; /* SPU context save area. */
spinlock_t mmio_lock; /* protects mmio access */
- struct address_space *local_store;/* local store backing store */
+ struct address_space *local_store; /* local store mapping. */
+ struct address_space *mfc; /* 'mfc' area mappings. */
+ struct address_space *cntl; /* 'control' area mappings. */
+ struct address_space *signal1; /* 'signal1' area mappings. */
+ struct address_space *signal2; /* 'signal2' area mappings. */
enum { SPU_STATE_RUNNABLE, SPU_STATE_SAVED } state;
struct rw_semaphore state_sema;
@@ -125,7 +129,7 @@
extern struct file_operations spufs_context_fops;
/* context management */
-struct spu_context * alloc_spu_context(struct address_space *local_store);
+struct spu_context * alloc_spu_context(void);
void destroy_spu_context(struct kref *kref);
struct spu_context * get_spu_context(struct spu_context *ctx);
int put_spu_context(struct spu_context *ctx);