[POWERPC] spufs: move fault, lscsa_alloc and switch code to spufs module

Currently, part of the spufs code (switch.o, lscsa_alloc.o and fault.o)
is compiled directly into the kernel.

This change moves these components of spufs into the kernel.

The lscsa and switch objects are fairly straightforward to move in.

For the fault.o module, we split the fault-handling code into two
parts: a/p/p/c/spu_fault.c and a/p/p/c/spufs/fault.c. The former is for
the in-kernel spu_handle_mm_fault function, and we move the rest of the
fault-handling code into spufs.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/powerpc/platforms/cell/Makefile

@@ -19,7 +19,7 @@ spu-manage-$(CONFIG_PPC_CELLEB)		+= spu_manage.o
 spu-manage-$(CONFIG_PPC_CELL_NATIVE)	+= spu_manage.o
 
 obj-$(CONFIG_SPU_BASE)			+= spu_callbacks.o spu_base.o \
-					   spu_syscalls.o \
+					   spu_syscalls.o spu_fault.o \
 					   $(spu-priv1-y) \
 					   $(spu-manage-y) \
 					   spufs/

arch/powerpc/platforms/cell/spu_fault.c

@@ -0,0 +1,98 @@
+/*
+ * SPU mm fault handler
+ *
+ * (C) Copyright IBM Deutschland Entwicklung GmbH 2007
+ *
+ * Author: Arnd Bergmann <arndb@de.ibm.com>
+ * Author: Jeremy Kerr <jk@ozlabs.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+
+#include <asm/spu.h>
+#include <asm/spu_csa.h>
+
+/*
+ * This ought to be kept in sync with the powerpc specific do_page_fault
+ * function. Currently, there are a few corner cases that we haven't had
+ * to handle fortunately.
+ */
+int spu_handle_mm_fault(struct mm_struct *mm, unsigned long ea,
+		unsigned long dsisr, unsigned *flt)
+{
+	struct vm_area_struct *vma;
+	unsigned long is_write;
+	int ret;
+
+#if 0
+	if (!IS_VALID_EA(ea)) {
+		return -EFAULT;
+	}
+#endif /* XXX */
+	if (mm == NULL) {
+		return -EFAULT;
+	}
+	if (mm->pgd == NULL) {
+		return -EFAULT;
+	}
+
+	down_read(&mm->mmap_sem);
+	vma = find_vma(mm, ea);
+	if (!vma)
+		goto bad_area;
+	if (vma->vm_start <= ea)
+		goto good_area;
+	if (!(vma->vm_flags & VM_GROWSDOWN))
+		goto bad_area;
+	if (expand_stack(vma, ea))
+		goto bad_area;
+good_area:
+	is_write = dsisr & MFC_DSISR_ACCESS_PUT;
+	if (is_write) {
+		if (!(vma->vm_flags & VM_WRITE))
+			goto bad_area;
+	} else {
+		if (dsisr & MFC_DSISR_ACCESS_DENIED)
+			goto bad_area;
+		if (!(vma->vm_flags & (VM_READ | VM_EXEC)))
+			goto bad_area;
+	}
+	ret = 0;
+	*flt = handle_mm_fault(mm, vma, ea, is_write);
+	if (unlikely(*flt & VM_FAULT_ERROR)) {
+		if (*flt & VM_FAULT_OOM) {
+			ret = -ENOMEM;
+			goto bad_area;
+		} else if (*flt & VM_FAULT_SIGBUS) {
+			ret = -EFAULT;
+			goto bad_area;
+		}
+		BUG();
+	}
+	if (*flt & VM_FAULT_MAJOR)
+		current->maj_flt++;
+	else
+		current->min_flt++;
+	up_read(&mm->mmap_sem);
+	return ret;
+
+bad_area:
+	up_read(&mm->mmap_sem);
+	return -EFAULT;
+}
+EXPORT_SYMBOL_GPL(spu_handle_mm_fault);

arch/powerpc/platforms/cell/spufs/Makefile

@@ -1,8 +1,8 @@
-obj-y += switch.o fault.o lscsa_alloc.o
 
 obj-$(CONFIG_SPU_FS) += spufs.o
 spufs-y += inode.o file.o context.o syscalls.o coredump.o
 spufs-y += sched.o backing_ops.o hw_ops.o run.o gang.o
+spufs-y += switch.o fault.o lscsa_alloc.o
 
 # Rules to build switch.o with the help of SPU tool chain
 SPU_CROSS	:= spu-

arch/powerpc/platforms/cell/spufs/fault.c

@@ -28,75 +28,6 @@
 
 #include "spufs.h"
 
-/*
- * This ought to be kept in sync with the powerpc specific do_page_fault
- * function. Currently, there are a few corner cases that we haven't had
- * to handle fortunately.
- */
-static int spu_handle_mm_fault(struct mm_struct *mm, unsigned long ea,
-		unsigned long dsisr, unsigned *flt)
-{
-	struct vm_area_struct *vma;
-	unsigned long is_write;
-	int ret;
-
-#if 0
-	if (!IS_VALID_EA(ea)) {
-		return -EFAULT;
-	}
-#endif /* XXX */
-	if (mm == NULL) {
-		return -EFAULT;
-	}
-	if (mm->pgd == NULL) {
-		return -EFAULT;
-	}
-
-	down_read(&mm->mmap_sem);
-	vma = find_vma(mm, ea);
-	if (!vma)
-		goto bad_area;
-	if (vma->vm_start <= ea)
-		goto good_area;
-	if (!(vma->vm_flags & VM_GROWSDOWN))
-		goto bad_area;
-	if (expand_stack(vma, ea))
-		goto bad_area;
-good_area:
-	is_write = dsisr & MFC_DSISR_ACCESS_PUT;
-	if (is_write) {
-		if (!(vma->vm_flags & VM_WRITE))
-			goto bad_area;
-	} else {
-		if (dsisr & MFC_DSISR_ACCESS_DENIED)
-			goto bad_area;
-		if (!(vma->vm_flags & (VM_READ | VM_EXEC)))
-			goto bad_area;
-	}
-	ret = 0;
-	*flt = handle_mm_fault(mm, vma, ea, is_write);
-	if (unlikely(*flt & VM_FAULT_ERROR)) {
-		if (*flt & VM_FAULT_OOM) {
-			ret = -ENOMEM;
-			goto bad_area;
-		} else if (*flt & VM_FAULT_SIGBUS) {
-			ret = -EFAULT;
-			goto bad_area;
-		}
-		BUG();
-	}
-	if (*flt & VM_FAULT_MAJOR)
-		current->maj_flt++;
-	else
-		current->min_flt++;
-	up_read(&mm->mmap_sem);
-	return ret;
-
-bad_area:
-	up_read(&mm->mmap_sem);
-	return -EFAULT;
-}
-
 static void spufs_handle_dma_error(struct spu_context *ctx,
 				unsigned long ea, int type)
 {
@@ -138,7 +69,6 @@ void spufs_dma_callback(struct spu *spu, int type)
 {
 	spufs_handle_dma_error(spu->ctx, spu->dar, type);
 }
-EXPORT_SYMBOL_GPL(spufs_dma_callback);
 
 /*
  * bottom half handler for page faults, we can't do this from
@@ -227,4 +157,3 @@ int spufs_handle_class1(struct spu_context *ctx)
 	spuctx_switch_state(ctx, SPU_UTIL_SYSTEM);
 	return ret;
 }
-EXPORT_SYMBOL_GPL(spufs_handle_class1);

arch/powerpc/platforms/cell/spufs/lscsa_alloc.c

@@ -28,6 +28,8 @@
 #include <asm/spu_csa.h>
 #include <asm/mmu.h>
 
+#include "spufs.h"
+
 static int spu_alloc_lscsa_std(struct spu_state *csa)
 {
 	struct spu_lscsa *lscsa;

arch/powerpc/platforms/cell/spufs/sched.c

@@ -892,6 +892,38 @@ static int spusched_thread(void *unused)
 	return 0;
 }
 
+void spuctx_switch_state(struct spu_context *ctx,
+		enum spu_utilization_state new_state)
+{
+	unsigned long long curtime;
+	signed long long delta;
+	struct timespec ts;
+	struct spu *spu;
+	enum spu_utilization_state old_state;
+
+	ktime_get_ts(&ts);
+	curtime = timespec_to_ns(&ts);
+	delta = curtime - ctx->stats.tstamp;
+
+	WARN_ON(!mutex_is_locked(&ctx->state_mutex));
+	WARN_ON(delta < 0);
+
+	spu = ctx->spu;
+	old_state = ctx->stats.util_state;
+	ctx->stats.util_state = new_state;
+	ctx->stats.tstamp = curtime;
+
+	/*
+	 * Update the physical SPU utilization statistics.
+	 */
+	if (spu) {
+		ctx->stats.times[old_state] += delta;
+		spu->stats.times[old_state] += delta;
+		spu->stats.util_state = new_state;
+		spu->stats.tstamp = curtime;
+	}
+}
+
 #define LOAD_INT(x) ((x) >> FSHIFT)
 #define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100)
 

arch/powerpc/platforms/cell/spufs/spufs.h

@@ -307,41 +307,16 @@ struct spufs_coredump_reader {
 extern struct spufs_coredump_reader spufs_coredump_read[];
 extern int spufs_coredump_num_notes;
 
-/*
- * This function is a little bit too large for an inline, but
- * as fault.c is built into the kernel we can't move it out of
- * line.
- */
-static inline void spuctx_switch_state(struct spu_context *ctx,
-		enum spu_utilization_state new_state)
-{
-	unsigned long long curtime;
-	signed long long delta;
-	struct timespec ts;
-	struct spu *spu;
-	enum spu_utilization_state old_state;
-
-	ktime_get_ts(&ts);
-	curtime = timespec_to_ns(&ts);
-	delta = curtime - ctx->stats.tstamp;
-
-	WARN_ON(!mutex_is_locked(&ctx->state_mutex));
-	WARN_ON(delta < 0);
-
-	spu = ctx->spu;
-	old_state = ctx->stats.util_state;
-	ctx->stats.util_state = new_state;
-	ctx->stats.tstamp = curtime;
-
-	/*
-	 * Update the physical SPU utilization statistics.
-	 */
-	if (spu) {
-		ctx->stats.times[old_state] += delta;
-		spu->stats.times[old_state] += delta;
-		spu->stats.util_state = new_state;
-		spu->stats.tstamp = curtime;
-	}
-}
+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);
+
+extern void spuctx_switch_state(struct spu_context *ctx,
+		enum spu_utilization_state new_state);
 
 #endif

arch/powerpc/platforms/cell/spufs/switch.c

@@ -48,6 +48,8 @@
 #include <asm/spu_csa.h>
 #include <asm/mmu_context.h>
 
+#include "spufs.h"
+
 #include "spu_save_dump.h"
 #include "spu_restore_dump.h"
 
@@ -2187,10 +2189,8 @@ int spu_init_csa(struct spu_state *csa)
 
 	return 0;
 }
-EXPORT_SYMBOL_GPL(spu_init_csa);
 
 void spu_fini_csa(struct spu_state *csa)
 {
 	spu_free_lscsa(csa);
 }
-EXPORT_SYMBOL_GPL(spu_fini_csa);

include/asm-powerpc/spu.h

@@ -283,6 +283,8 @@ void spu_remove_sysdev_attr(struct sysdev_attribute *attr);
 int spu_add_sysdev_attr_group(struct attribute_group *attrs);
 void spu_remove_sysdev_attr_group(struct attribute_group *attrs);
 
+int spu_handle_mm_fault(struct mm_struct *mm, unsigned long ea,
+		unsigned long dsisr, unsigned *flt);
 
 /*
  * Notifier blocks:

include/asm-powerpc/spu_csa.h

@@ -259,15 +259,6 @@ struct spu_state {
 	spinlock_t register_lock;
 };
 
-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__ */
 #endif /* !__ASSEMBLY__ */