[PATCH] mark f_ops const in the inode

Mark the f_ops members of inodes as const, as well as fix the
ripple-through this causes by places that copy this f_ops and then "do
stuff" with it.
Signed-off-by: NArjan van de Ven <arjan@infradead.org>
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

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

@@ -103,7 +103,7 @@ spufs_setattr(struct dentry *dentry, struct iattr *attr)
 
 static int
 spufs_new_file(struct super_block *sb, struct dentry *dentry,
-		struct file_operations *fops, int mode,
+		const struct file_operations *fops, int mode,
 		struct spu_context *ctx)
 {
 	static struct inode_operations spufs_file_iops = {

arch/ppc/kernel/ppc_htab.c

@@ -52,7 +52,7 @@ static int ppc_htab_open(struct inode *inode, struct file *file)
 	return single_open(file, ppc_htab_show, NULL);
 }
 
-struct file_operations ppc_htab_operations = {
+const struct file_operations ppc_htab_operations = {
 	.open		= ppc_htab_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,

drivers/char/drm/drm_fops.c

@@ -175,7 +175,7 @@ int drm_stub_open(struct inode *inode, struct file *filp)
 	drm_device_t *dev = NULL;
 	int minor = iminor(inode);
 	int err = -ENODEV;
-	struct file_operations *old_fops;
+	const struct file_operations *old_fops;
 
 	DRM_DEBUG("\n");
 

drivers/char/drm/i810_dma.c

@@ -126,7 +126,7 @@ static int i810_map_buffer(drm_buf_t * buf, struct file *filp)
 	drm_device_t *dev = priv->head->dev;
 	drm_i810_buf_priv_t *buf_priv = buf->dev_private;
 	drm_i810_private_t *dev_priv = dev->dev_private;
-	struct file_operations *old_fops;
+	const struct file_operations *old_fops;
 	int retcode = 0;
 
 	if (buf_priv->currently_mapped == I810_BUF_MAPPED)

drivers/char/drm/i830_dma.c

@@ -128,7 +128,7 @@ static int i830_map_buffer(drm_buf_t * buf, struct file *filp)
 	drm_device_t *dev = priv->head->dev;
 	drm_i830_buf_priv_t *buf_priv = buf->dev_private;
 	drm_i830_private_t *dev_priv = dev->dev_private;
-	struct file_operations *old_fops;
+	const struct file_operations *old_fops;
 	unsigned long virtual;
 	int retcode = 0;
 

drivers/char/mem.c

@@ -899,7 +899,7 @@ static const struct {
 	unsigned int		minor;
 	char			*name;
 	umode_t			mode;
-	struct file_operations	*fops;
+	const struct file_operations	*fops;
 } devlist[] = { /* list of minor devices */
 	{1, "mem",     S_IRUSR | S_IWUSR | S_IRGRP, &mem_fops},
 	{2, "kmem",    S_IRUSR | S_IWUSR | S_IRGRP, &kmem_fops},

drivers/char/misc.c

@@ -129,7 +129,7 @@ static int misc_open(struct inode * inode, struct file * file)
 	int minor = iminor(inode);
 	struct miscdevice *c;
 	int err = -ENODEV;
-	struct file_operations *old_fops, *new_fops = NULL;
+	const struct file_operations *old_fops, *new_fops = NULL;
 	
 	down(&misc_sem);
 	

drivers/input/input.c

@@ -923,7 +923,7 @@ void input_unregister_handler(struct input_handler *handler)
 static int input_open_file(struct inode *inode, struct file *file)
 {
 	struct input_handler *handler = input_table[iminor(inode) >> 5];
-	struct file_operations *old_fops, *new_fops = NULL;
+	const struct file_operations *old_fops, *new_fops = NULL;
 	int err;
 
 	/* No load-on-demand here? */

drivers/isdn/capi/kcapi_proc.c

@@ -233,7 +233,7 @@ static struct file_operations proc_applstats_ops = {
 };
 
 static void
-create_seq_entry(char *name, mode_t mode, struct file_operations *f)
+create_seq_entry(char *name, mode_t mode, const struct file_operations *f)
 {
 	struct proc_dir_entry *entry;
 	entry = create_proc_entry(name, mode, NULL);

drivers/media/dvb/dvb-core/dvbdev.c

@@ -86,7 +86,7 @@ static int dvb_device_open(struct inode *inode, struct file *file)
 
 	if (dvbdev && dvbdev->fops) {
 		int err = 0;
-		struct file_operations *old_fops;
+		const struct file_operations *old_fops;
 
 		file->private_data = dvbdev;
 		old_fops = file->f_op;

drivers/media/video/videodev.c

@@ -97,7 +97,7 @@ static int video_open(struct inode *inode, struct file *file)
 	unsigned int minor = iminor(inode);
 	int err = 0;
 	struct video_device *vfl;
-	struct file_operations *old_fops;
+	const struct file_operations *old_fops;
 
 	if(minor>=VIDEO_NUM_DEVICES)
 		return -ENODEV;

drivers/message/i2o/i2o_proc.c

@@ -56,7 +56,7 @@
 typedef struct _i2o_proc_entry_t {
 	char *name;		/* entry name */
 	mode_t mode;		/* mode */
-	struct file_operations *fops;	/* open function */
+	const struct file_operations *fops;	/* open function */
 } i2o_proc_entry;
 
 /* global I2O /proc/i2o entry */

drivers/oprofile/oprofilefs.c

@@ -130,7 +130,7 @@ static struct file_operations ulong_ro_fops = {
 
 
 static struct dentry * __oprofilefs_create_file(struct super_block * sb,
-	struct dentry * root, char const * name, struct file_operations * fops,
+	struct dentry * root, char const * name, const struct file_operations * fops,
 	int perm)
 {
 	struct dentry * dentry;
@@ -203,7 +203,7 @@ int oprofilefs_create_ro_atomic(struct super_block * sb, struct dentry * root,
 
  
 int oprofilefs_create_file(struct super_block * sb, struct dentry * root,
-	char const * name, struct file_operations * fops)
+	char const * name, const struct file_operations * fops)
 {
 	if (!__oprofilefs_create_file(sb, root, name, fops, 0644))
 		return -EFAULT;
@@ -212,7 +212,7 @@ int oprofilefs_create_file(struct super_block * sb, struct dentry * root,
 
 
 int oprofilefs_create_file_perm(struct super_block * sb, struct dentry * root,
-	char const * name, struct file_operations * fops, int perm)
+	char const * name, const struct file_operations * fops, int perm)
 {
 	if (!__oprofilefs_create_file(sb, root, name, fops, perm))
 		return -EFAULT;

drivers/telephony/phonedev.c

@@ -49,7 +49,7 @@ static int phone_open(struct inode *inode, struct file *file)
 	unsigned int minor = iminor(inode);
 	int err = 0;
 	struct phone_device *p;
-	struct file_operations *old_fops, *new_fops = NULL;
+	const struct file_operations *old_fops, *new_fops = NULL;
 
 	if (minor >= PHONE_NUM_DEVICES)
 		return -ENODEV;

drivers/usb/core/file.c

@@ -24,15 +24,15 @@
 #include "usb.h"
 
 #define MAX_USB_MINORS	256
-static struct file_operations *usb_minors[MAX_USB_MINORS];
+static const struct file_operations *usb_minors[MAX_USB_MINORS];
 static DEFINE_SPINLOCK(minor_lock);
 
 static int usb_open(struct inode * inode, struct file * file)
 {
 	int minor = iminor(inode);
-	struct file_operations *c;
+	const struct file_operations *c;
 	int err = -ENODEV;
-	struct file_operations *old_fops, *new_fops = NULL;
+	const struct file_operations *old_fops, *new_fops = NULL;
 
 	spin_lock (&minor_lock);
 	c = usb_minors[minor];

drivers/usb/gadget/inode.c

@@ -1581,7 +1581,7 @@ static void destroy_ep_files (struct dev_data *dev)
 
 static struct inode *
 gadgetfs_create_file (struct super_block *sb, char const *name,
-		void *data, struct file_operations *fops,
+		void *data, const struct file_operations *fops,
 		struct dentry **dentry_p);
 
 static int activate_ep_files (struct dev_data *dev)
@@ -1955,7 +1955,7 @@ module_param (default_perm, uint, 0644);
 
 static struct inode *
 gadgetfs_make_inode (struct super_block *sb,
-		void *data, struct file_operations *fops,
+		void *data, const struct file_operations *fops,
 		int mode)
 {
 	struct inode *inode = new_inode (sb);
@@ -1979,7 +1979,7 @@ gadgetfs_make_inode (struct super_block *sb,
  */
 static struct inode *
 gadgetfs_create_file (struct super_block *sb, char const *name,
-		void *data, struct file_operations *fops,
+		void *data, const struct file_operations *fops,
 		struct dentry **dentry_p)
 {
 	struct dentry	*dentry;

fs/char_dev.c

@@ -250,7 +250,7 @@ int alloc_chrdev_region(dev_t *dev, unsigned baseminor, unsigned count,
 }
 
 int register_chrdev(unsigned int major, const char *name,
-		    struct file_operations *fops)
+		    const struct file_operations *fops)
 {
 	struct char_device_struct *cd;
 	struct cdev *cdev;
@@ -473,7 +473,7 @@ struct cdev *cdev_alloc(void)
 	return p;
 }
 
-void cdev_init(struct cdev *cdev, struct file_operations *fops)
+void cdev_init(struct cdev *cdev, const struct file_operations *fops)
 {
 	memset(cdev, 0, sizeof *cdev);
 	INIT_LIST_HEAD(&cdev->list);

fs/debugfs/inode.c

@@ -191,7 +191,7 @@ static int debugfs_create_by_name(const char *name, mode_t mode,
  */
 struct dentry *debugfs_create_file(const char *name, mode_t mode,
 				   struct dentry *parent, void *data,
-				   struct file_operations *fops)
+				   const struct file_operations *fops)
 {
 	struct dentry *dentry = NULL;
 	int error;

fs/inode.c

@@ -104,7 +104,7 @@ static struct inode *alloc_inode(struct super_block *sb)
 {
 	static struct address_space_operations empty_aops;
 	static struct inode_operations empty_iops;
-	static struct file_operations empty_fops;
+	static const struct file_operations empty_fops;
 	struct inode *inode;
 
 	if (sb->s_op->alloc_inode)

fs/nfsd/vfs.c

@@ -706,7 +706,7 @@ nfsd_close(struct file *filp)
  * after it.
  */
 static inline int nfsd_dosync(struct file *filp, struct dentry *dp,
-			      struct file_operations *fop)
+			      const struct file_operations *fop)
 {
 	struct inode *inode = dp->d_inode;
 	int (*fsync) (struct file *, struct dentry *, int);

fs/proc/generic.c

@@ -560,7 +560,7 @@ static void proc_kill_inodes(struct proc_dir_entry *de)
 		struct file * filp = list_entry(p, struct file, f_u.fu_list);
 		struct dentry * dentry = filp->f_dentry;
 		struct inode * inode;
-		struct file_operations *fops;
+		const struct file_operations *fops;
 
 		if (dentry->d_op != &proc_dentry_operations)
 			continue;

fs/proc/internal.h

@@ -30,7 +30,7 @@ do {						\
 
 #endif
 
-extern void create_seq_entry(char *name, mode_t mode, struct file_operations *f);
+extern void create_seq_entry(char *name, mode_t mode, const struct file_operations *f);
 extern int proc_exe_link(struct inode *, struct dentry **, struct vfsmount **);
 extern int proc_tid_stat(struct task_struct *,  char *);
 extern int proc_tgid_stat(struct task_struct *, char *);

fs/proc/proc_misc.c

@@ -731,7 +731,7 @@ static struct file_operations proc_sysrq_trigger_operations = {
 
 struct proc_dir_entry *proc_root_kcore;
 
-void create_seq_entry(char *name, mode_t mode, struct file_operations *f)
+void create_seq_entry(char *name, mode_t mode, const struct file_operations *f)
 {
 	struct proc_dir_entry *entry;
 	entry = create_proc_entry(name, mode, NULL);

fs/select.c

@@ -220,7 +220,7 @@ int do_select(int n, fd_set_bits *fds, s64 *timeout)
 		for (i = 0; i < n; ++rinp, ++routp, ++rexp) {
 			unsigned long in, out, ex, all_bits, bit = 1, mask, j;
 			unsigned long res_in = 0, res_out = 0, res_ex = 0;
-			struct file_operations *f_op = NULL;
+			const struct file_operations *f_op = NULL;
 			struct file *file = NULL;
 
 			in = *inp++; out = *outp++; ex = *exp++;

include/linux/cdev.h

@@ -5,13 +5,13 @@
 struct cdev {
 	struct kobject kobj;
 	struct module *owner;
-	struct file_operations *ops;
+	const struct file_operations *ops;
 	struct list_head list;
 	dev_t dev;
 	unsigned int count;
 };
 
-void cdev_init(struct cdev *, struct file_operations *);
+void cdev_init(struct cdev *, const struct file_operations *);
 
 struct cdev *cdev_alloc(void);
 

include/linux/debugfs.h

@@ -29,7 +29,7 @@ struct debugfs_blob_wrapper {
 #if defined(CONFIG_DEBUG_FS)
 struct dentry *debugfs_create_file(const char *name, mode_t mode,
 				   struct dentry *parent, void *data,
-				   struct file_operations *fops);
+				   const struct file_operations *fops);
 
 struct dentry *debugfs_create_dir(const char *name, struct dentry *parent);
 

include/linux/fs.h

@@ -496,7 +496,7 @@ struct inode {
 	struct mutex		i_mutex;
 	struct rw_semaphore	i_alloc_sem;
 	struct inode_operations	*i_op;
-	struct file_operations	*i_fop;	/* former ->i_op->default_file_ops */
+	const struct file_operations	*i_fop;	/* former ->i_op->default_file_ops */
 	struct super_block	*i_sb;
 	struct file_lock	*i_flock;
 	struct address_space	*i_mapping;
@@ -636,7 +636,7 @@ struct file {
 	} f_u;
 	struct dentry		*f_dentry;
 	struct vfsmount         *f_vfsmnt;
-	struct file_operations	*f_op;
+	const struct file_operations	*f_op;
 	atomic_t		f_count;
 	unsigned int 		f_flags;
 	mode_t			f_mode;
@@ -1414,7 +1414,7 @@ extern void bd_release_from_disk(struct block_device *, struct gendisk *);
 extern int alloc_chrdev_region(dev_t *, unsigned, unsigned, const char *);
 extern int register_chrdev_region(dev_t, unsigned, const char *);
 extern int register_chrdev(unsigned int, const char *,
-			   struct file_operations *);
+			   const struct file_operations *);
 extern int unregister_chrdev(unsigned int, const char *);
 extern void unregister_chrdev_region(dev_t, unsigned);
 extern int chrdev_open(struct inode *, struct file *);

include/linux/input.h

@@ -957,7 +957,7 @@ struct input_handler {
 	struct input_handle* (*connect)(struct input_handler *handler, struct input_dev *dev, struct input_device_id *id);
 	void (*disconnect)(struct input_handle *handle);
 
-	struct file_operations *fops;
+	const struct file_operations *fops;
 	int minor;
 	char *name;
 

include/linux/miscdevice.h

@@ -36,7 +36,7 @@ struct class_device;
 struct miscdevice  {
 	int minor;
 	const char *name;
-	struct file_operations *fops;
+	const struct file_operations *fops;
 	struct list_head list;
 	struct device *dev;
 	struct class_device *class;

include/linux/oprofile.h

@@ -84,10 +84,10 @@ void oprofile_add_trace(unsigned long eip);
  * the specified file operations.
  */
 int oprofilefs_create_file(struct super_block * sb, struct dentry * root,
-	char const * name, struct file_operations * fops);
+	char const * name, const struct file_operations * fops);
 
 int oprofilefs_create_file_perm(struct super_block * sb, struct dentry * root,
-	char const * name, struct file_operations * fops, int perm);
+	char const * name, const struct file_operations * fops, int perm);
  
 /** Create a file for read/write access to an unsigned long. */
 int oprofilefs_create_ulong(struct super_block * sb, struct dentry * root,

include/linux/proc_fs.h

@@ -58,7 +58,7 @@ struct proc_dir_entry {
 	gid_t gid;
 	loff_t size;
 	struct inode_operations * proc_iops;
-	struct file_operations * proc_fops;
+	const struct file_operations * proc_fops;
 	get_info_t *get_info;
 	struct module *owner;
 	struct proc_dir_entry *next, *parent, *subdir;
@@ -189,7 +189,7 @@ static inline struct proc_dir_entry *proc_net_create(const char *name,
 }
 
 static inline struct proc_dir_entry *proc_net_fops_create(const char *name,
-	mode_t mode, struct file_operations *fops)
+	mode_t mode, const struct file_operations *fops)
 {
 	struct proc_dir_entry *res = create_proc_entry(name, mode, proc_net);
 	if (res)

include/linux/sound.h

@@ -30,12 +30,12 @@
  */
  
 struct device;
-extern int register_sound_special(struct file_operations *fops, int unit);
-extern int register_sound_special_device(struct file_operations *fops, int unit, struct device *dev);
-extern int register_sound_mixer(struct file_operations *fops, int dev);
-extern int register_sound_midi(struct file_operations *fops, int dev);
-extern int register_sound_dsp(struct file_operations *fops, int dev);
-extern int register_sound_synth(struct file_operations *fops, int dev);
+extern int register_sound_special(const struct file_operations *fops, int unit);
+extern int register_sound_special_device(const struct file_operations *fops, int unit, struct device *dev);
+extern int register_sound_mixer(const struct file_operations *fops, int dev);
+extern int register_sound_midi(const struct file_operations *fops, int dev);
+extern int register_sound_dsp(const struct file_operations *fops, int dev);
+extern int register_sound_synth(const struct file_operations *fops, int dev);
 
 extern void unregister_sound_special(int unit);
 extern void unregister_sound_mixer(int unit);

include/linux/sunrpc/stats.h

@@ -50,7 +50,7 @@ struct proc_dir_entry *	rpc_proc_register(struct rpc_stat *);
 void			rpc_proc_unregister(const char *);
 void			rpc_proc_zero(struct rpc_program *);
 struct proc_dir_entry *	svc_proc_register(struct svc_stat *,
-					  struct file_operations *);
+					  const struct file_operations *);
 void			svc_proc_unregister(const char *);
 
 void			svc_seq_show(struct seq_file *,
@@ -65,7 +65,7 @@ static inline void rpc_proc_unregister(const char *p) {}
 static inline void rpc_proc_zero(struct rpc_program *p) {}
 
 static inline struct proc_dir_entry *svc_proc_register(struct svc_stat *s,
-						       struct file_operations *f) { return NULL; }
+						       const struct file_operations *f) { return NULL; }
 static inline void svc_proc_unregister(const char *p) {}
 
 static inline void svc_seq_show(struct seq_file *seq,

include/linux/usb.h

@@ -615,7 +615,7 @@ extern struct bus_type usb_bus_type;
  */
 struct usb_class_driver {
 	char *name;
-	struct file_operations *fops;
+	const struct file_operations *fops;
 	int minor_base;
 };
 

include/linux/videodev2.h

@@ -75,7 +75,7 @@ struct video_device
 	int minor;
 
 	/* device ops + callbacks */
-	struct file_operations *fops;
+	const struct file_operations *fops;
 	void (*release)(struct video_device *vfd);
 
 

include/sound/core.h

@@ -186,7 +186,7 @@ struct snd_minor {
 	int type;			/* SNDRV_DEVICE_TYPE_XXX */
 	int card;			/* card number */
 	int device;			/* device number */
-	struct file_operations *f_ops;	/* file operations */
+	const struct file_operations *f_ops;	/* file operations */
 	void *private_data;		/* private data for f_ops->open */
 	char name[0];			/* device name (keep at the end of
 								structure) */
@@ -200,14 +200,14 @@ extern int snd_ecards_limit;
 void snd_request_card(int card);
 
 int snd_register_device(int type, struct snd_card *card, int dev,
-			struct file_operations *f_ops, void *private_data,
+			const struct file_operations *f_ops, void *private_data,
 			const char *name);
 int snd_unregister_device(int type, struct snd_card *card, int dev);
 void *snd_lookup_minor_data(unsigned int minor, int type);
 
 #ifdef CONFIG_SND_OSSEMUL
 int snd_register_oss_device(int type, struct snd_card *card, int dev,
-			    struct file_operations *f_ops, void *private_data,
+			    const struct file_operations *f_ops, void *private_data,
 			    const char *name);
 int snd_unregister_oss_device(int type, struct snd_card *card, int dev);
 void *snd_lookup_oss_minor_data(unsigned int minor, int type);

net/sunrpc/rpc_pipe.c

@@ -395,7 +395,7 @@ enum {
  */
 struct rpc_filelist {
 	char *name;
-	struct file_operations *i_fop;
+	const struct file_operations *i_fop;
 	int mode;
 };
 

net/sunrpc/stats.c

@@ -225,7 +225,7 @@ EXPORT_SYMBOL(rpc_print_iostats);
  * Register/unregister RPC proc files
  */
 static inline struct proc_dir_entry *
-do_register(const char *name, void *data, struct file_operations *fops)
+do_register(const char *name, void *data, const struct file_operations *fops)
 {
 	struct proc_dir_entry *ent;
 
@@ -253,7 +253,7 @@ rpc_proc_unregister(const char *name)
 }
 
 struct proc_dir_entry *
-svc_proc_register(struct svc_stat *statp, struct file_operations *fops)
+svc_proc_register(struct svc_stat *statp, const struct file_operations *fops)
 {
 	return do_register(statp->program->pg_name, statp, fops);
 }

sound/core/init.c

@@ -223,7 +223,8 @@ int snd_card_disconnect(struct snd_card *card)
 	struct snd_monitor_file *mfile;
 	struct file *file;
 	struct snd_shutdown_f_ops *s_f_ops;
-	struct file_operations *f_ops, *old_f_ops;
+	struct file_operations *f_ops;
+	const struct file_operations *old_f_ops;
 	int err;
 
 	spin_lock(&card->files_lock);

sound/core/sound.c

@@ -137,7 +137,7 @@ static int snd_open(struct inode *inode, struct file *file)
 {
 	unsigned int minor = iminor(inode);
 	struct snd_minor *mptr = NULL;
-	struct file_operations *old_fops;
+	const struct file_operations *old_fops;
 	int err = 0;
 
 	if (minor >= ARRAY_SIZE(snd_minors))
@@ -240,7 +240,7 @@ static int snd_kernel_minor(int type, struct snd_card *card, int dev)
  * Retrurns zero if successful, or a negative error code on failure.
  */
 int snd_register_device(int type, struct snd_card *card, int dev,
-			struct file_operations *f_ops, void *private_data,
+			const struct file_operations *f_ops, void *private_data,
 			const char *name)
 {
 	int minor;

sound/core/sound_oss.c

@@ -95,7 +95,7 @@ static int snd_oss_kernel_minor(int type, struct snd_card *card, int dev)
 }
 
 int snd_register_oss_device(int type, struct snd_card *card, int dev,
-			    struct file_operations *f_ops, void *private_data,
+			    const struct file_operations *f_ops, void *private_data,
 			    const char *name)
 {
 	int minor = snd_oss_kernel_minor(type, card, dev);

sound/sound_core.c

@@ -53,7 +53,7 @@
 struct sound_unit
 {
 	int unit_minor;
-	struct file_operations *unit_fops;
+	const struct file_operations *unit_fops;
 	struct sound_unit *next;
 	char name[32];
 };
@@ -73,7 +73,7 @@ EXPORT_SYMBOL(sound_class);
  *	join into it. Called with the lock asserted
  */
 
-static int __sound_insert_unit(struct sound_unit * s, struct sound_unit **list, struct file_operations *fops, int index, int low, int top)
+static int __sound_insert_unit(struct sound_unit * s, struct sound_unit **list, const struct file_operations *fops, int index, int low, int top)
 {
 	int n=low;
 
@@ -153,7 +153,7 @@ static DEFINE_SPINLOCK(sound_loader_lock);
  *	list. Acquires locks as needed
  */
 
-static int sound_insert_unit(struct sound_unit **list, struct file_operations *fops, int index, int low, int top, const char *name, umode_t mode, struct device *dev)
+static int sound_insert_unit(struct sound_unit **list, const struct file_operations *fops, int index, int low, int top, const char *name, umode_t mode, struct device *dev)
 {
 	struct sound_unit *s = kmalloc(sizeof(*s), GFP_KERNEL);
 	int r;
@@ -237,7 +237,7 @@ static struct sound_unit *chains[SOUND_STEP];
  *	a negative error code is returned.
  */
  
-int register_sound_special_device(struct file_operations *fops, int unit,
+int register_sound_special_device(const struct file_operations *fops, int unit,
 				  struct device *dev)
 {
 	const int chain = unit % SOUND_STEP;
@@ -301,7 +301,7 @@ int register_sound_special_device(struct file_operations *fops, int unit,
  
 EXPORT_SYMBOL(register_sound_special_device);
 
-int register_sound_special(struct file_operations *fops, int unit)
+int register_sound_special(const struct file_operations *fops, int unit)
 {
 	return register_sound_special_device(fops, unit, NULL);
 }
@@ -318,7 +318,7 @@ EXPORT_SYMBOL(register_sound_special);
  *	number is returned, on failure a negative error code is returned.
  */
 
-int register_sound_mixer(struct file_operations *fops, int dev)
+int register_sound_mixer(const struct file_operations *fops, int dev)
 {
 	return sound_insert_unit(&chains[0], fops, dev, 0, 128,
 				 "mixer", S_IRUSR | S_IWUSR, NULL);
@@ -336,7 +336,7 @@ EXPORT_SYMBOL(register_sound_mixer);
  *	number is returned, on failure a negative error code is returned.
  */
 
-int register_sound_midi(struct file_operations *fops, int dev)
+int register_sound_midi(const struct file_operations *fops, int dev)
 {
 	return sound_insert_unit(&chains[2], fops, dev, 2, 130,
 				 "midi", S_IRUSR | S_IWUSR, NULL);
@@ -362,7 +362,7 @@ EXPORT_SYMBOL(register_sound_midi);
  *	and will always allocate them as a matching pair - eg dsp3/audio3
  */
 
-int register_sound_dsp(struct file_operations *fops, int dev)
+int register_sound_dsp(const struct file_operations *fops, int dev)
 {
 	return sound_insert_unit(&chains[3], fops, dev, 3, 131,
 				 "dsp", S_IWUSR | S_IRUSR, NULL);
@@ -381,7 +381,7 @@ EXPORT_SYMBOL(register_sound_dsp);
  */
 
 
-int register_sound_synth(struct file_operations *fops, int dev)
+int register_sound_synth(const struct file_operations *fops, int dev)
 {
 	return sound_insert_unit(&chains[9], fops, dev, 9, 137,
 				 "synth", S_IRUSR | S_IWUSR, NULL);
@@ -501,7 +501,7 @@ int soundcore_open(struct inode *inode, struct file *file)
 	int chain;
 	int unit = iminor(inode);
 	struct sound_unit *s;
-	struct file_operations *new_fops = NULL;
+	const struct file_operations *new_fops = NULL;
 
 	chain=unit&0x0F;
 	if(chain==4 || chain==5)	/* dsp/audio/dsp16 */
@@ -540,7 +540,7 @@ int soundcore_open(struct inode *inode, struct file *file)
 		 * switching ->f_op in the first place.
 		 */
 		int err = 0;
-		struct file_operations *old_fops = file->f_op;
+		const struct file_operations *old_fops = file->f_op;
 		file->f_op = new_fops;
 		spin_unlock(&sound_loader_lock);
 		if(file->f_op->open)