file: remove fileops

Everyone is now overriding file's virtual functions; we can make them
pure virtual and remove fileops completely.

Signed-off-by: Avi Kivity <avi@cloudius-systems.com>

fs/vfs/kern_descrip.cc

@@ -152,60 +152,14 @@ int fget(int fd, struct file **out_fp)
     return 0;
 }
 
-file::file(unsigned flags, filetype_t type, void *opaque,
-           struct fileops *ops)
+file::file(unsigned flags, filetype_t type, void *opaque)
     : f_flags(flags)
     , f_count(1)
-    , f_ops(ops)
     , f_data(opaque)
     , f_type(type)
 {
     auto fp = this;
     TAILQ_INIT(&fp->f_poll_list);
-
-    if (ops) {
-        fo_init(fp);
-    }
-}
-
-int file::read(struct uio *uio, int flags)
-{
-    return f_ops->fo_read(this, uio, flags);
-}
-
-int file::write(struct uio *uio, int flags)
-{
-    return f_ops->fo_write(this, uio, flags);
-}
-
-int file::truncate(off_t len)
-{
-    return f_ops->fo_truncate(this, len);
-}
-
-int file::ioctl(u_long com, void *data)
-{
-    return f_ops->fo_ioctl(this, com, data);
-}
-
-int file::poll(int events)
-{
-    return f_ops->fo_poll(this, events);
-}
-
-int file::stat(struct stat* buf)
-{
-    return f_ops->fo_stat(this, buf);
-}
-
-int file::close()
-{
-    return f_ops->fo_close(this);
-}
-
-int file::chmod(mode_t mode)
-{
-    return f_ops->fo_chmod(this, mode);
 }
 
 void fhold(struct file* fp)
@@ -252,12 +206,6 @@ void file_setdata(file* fp, void* data)
     fp->f_data = data;
 }
 
- int
-fo_init(struct file *fp)
-{
-        return fp->f_ops->fo_init(fp);
-}
-
  int
 fo_read(struct file *fp, struct uio *uio, int flags)
 {

include/osv/file.h

@@ -62,7 +62,6 @@ typedef enum {
 } filetype_t;
 
 struct vnode;
-struct fileops;
 struct file;
 
 #define FDMAX       (0x4000)
@@ -74,25 +73,23 @@ struct file;
  * File structure
  */
 struct file {
-	file(unsigned flags, filetype_t type, void *opaque = nullptr,
-		struct fileops *ops = nullptr);
+	file(unsigned flags, filetype_t type, void *opaque = nullptr);
 	virtual ~file();
 	void operator delete(void *p) { osv::rcu_dispose(p); }
 
-	virtual int read(struct uio *uio, int flags);
-	virtual int write(struct uio *uio, int flags);
-	virtual int truncate(off_t len);
-	virtual int ioctl(u_long com, void *data);
-	virtual int poll(int events);
-	virtual int stat(struct stat* buf);
-	virtual int close();
-	virtual int chmod(mode_t mode);
+	virtual int read(struct uio *uio, int flags) = 0;
+	virtual int write(struct uio *uio, int flags) = 0;
+	virtual int truncate(off_t len) = 0;
+	virtual int ioctl(u_long com, void *data) = 0;
+	virtual int poll(int events) = 0;
+	virtual int stat(struct stat* buf) = 0;
+	virtual int close() = 0;
+	virtual int chmod(mode_t mode) = 0;
 
 	int		f_flags;	/* open flags */
 	int		f_count;	/* reference count, see below */
 	off_t		f_offset = 0;	/* current position in file */
 	struct dentry	*f_dentry = nullptr; /* dentry */
-	struct fileops	*f_ops;		/* file ops abstraction */
 	void		*f_data;        /* file descriptor specific data */
 	filetype_t	f_type;		/* descriptor type */
 	TAILQ_HEAD(, poll_link) f_poll_list; /* poll request list */
@@ -125,18 +122,6 @@ typedef int fo_close_t(struct file *fp);
 typedef int fo_chmod_t(struct file *fp, mode_t mode);
 
 
-struct fileops {
-	fo_init_t   *fo_init;
-	fo_rdwr_t   *fo_read;
-	fo_rdwr_t   *fo_write;
-	fo_truncate_t   *fo_truncate;
-	fo_ioctl_t  *fo_ioctl;
-	fo_poll_t   *fo_poll;
-	fo_stat_t   *fo_stat;
-	fo_close_t  *fo_close;
-	fo_chmod_t  *fo_chmod;
-};
-
 /* Alloc an fd for fp */
 int _fdalloc(struct file *fp, int *newfd, int min_fd);
 int fdalloc(struct file* fp, int *newfd);