* Implement ioctl support. On high level interface only

"restricted" ioctls are supported (which are defined with the
_IO(), _IOR(), _IOW() or _IOWR() macros).  Unrestricted ioctls
will only be allwed to CUSE (Character Device in Userspace)
servers.  Patch by Tejun Heo

4 files changed, 133 insertions, 13 deletions

diff --git a/include/fuse.h b/include/fuse.h
index 8d47bc5..2016ccc 100644
--- a/include/fuse.h
+++ b/include/fuse.h
@@ -31,6 +31,7 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/statvfs.h>
+#include <sys/uio.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -457,6 +458,22 @@ struct fuse_operations {
 	 * Reserved flags, don't set
 	 */
 	unsigned int flag_reserved : 31;
+
+	/**
+	 * Ioctl
+	 *
+	 * @flags will have FUSE_IOCTL_COMPAT set for 32bit ioctls in
+	 * 64bit environment.  The size and direction of @data is
+	 * determined by _IOC_*() decoding of @cmd.  For _IOC_NONE,
+	 * @data will be NULL, for _IOC_WRITE @data is out area, for
+	 * _IOC_READ in area and if both are set in/out area.  In all
+	 * non-NULL cases, the area is of _IOC_SIZE(@cmd) bytes.
+	 *
+	 * Introduced in version 2.9
+	 */
+	int (*ioctl) (const char *, int cmd, void *arg,
+		      struct fuse_file_info *, unsigned int flags, void *data);
+
 };
 
 /** Extra context that may be needed by some filesystems
@@ -689,6 +706,8 @@ int fuse_fs_removexattr(struct fuse_fs *fs, const char *path,
 			const char *name);
 int fuse_fs_bmap(struct fuse_fs *fs, const char *path, size_t blocksize,
 		 uint64_t *idx);
+int fuse_fs_ioctl(struct fuse_fs *fs, const char *path, int cmd, void *arg,
+		  struct fuse_file_info *fi, unsigned int flags, void *data);
 void fuse_fs_init(struct fuse_fs *fs, struct fuse_conn_info *conn);
 void fuse_fs_destroy(struct fuse_fs *fs);
 
diff --git a/include/fuse_common.h b/include/fuse_common.h
index 9bbc386..fb18b61 100644
--- a/include/fuse_common.h
+++ b/include/fuse_common.h
@@ -94,6 +94,21 @@ struct fuse_file_info {
 #define FUSE_CAP_BIG_WRITES	(1 << 5)
 
 /**
+ * Ioctl flags
+ *
+ * FUSE_IOCTL_COMPAT: 32bit compat ioctl on 64bit machine
+ * FUSE_IOCTL_UNRESTRICTED: not restricted to well-formed ioctls, retry allowed
+ * FUSE_IOCTL_RETRY: retry with new iovecs
+ *
+ * FUSE_IOCTL_MAX_IOV: maximum of in_iovecs + out_iovecs
+ */
+#define FUSE_IOCTL_COMPAT	(1 << 0)
+#define FUSE_IOCTL_UNRESTRICTED	(1 << 1)
+#define FUSE_IOCTL_RETRY	(1 << 2)
+
+#define FUSE_IOCTL_MAX_IOV	256
+
+/**
  * Connection information, passed to the ->init() method
  *
  * Some of the elements are read-write, these can be changed to
diff --git a/include/fuse_kernel.h b/include/fuse_kernel.h
index b37d969..eb28a35 100644
--- a/include/fuse_kernel.h
+++ b/include/fuse_kernel.h
@@ -1,6 +1,6 @@
 /*
     This file defines the kernel interface of FUSE
-    Copyright (C) 2001-2007  Miklos Szeredi <miklos@szeredi.hu>
+    Copyright (C) 2001-2008  Miklos Szeredi <miklos@szeredi.hu>
 
     This program can be distributed under the terms of the GNU GPL.
     See the file COPYING.
@@ -46,36 +46,28 @@
  *
  * 7.10
  *  - add nonseekable open flag
+ *
+ * 7.11
+ *  - add IOCTL message
  */
 
 #ifndef _LINUX_FUSE_H
 #define _LINUX_FUSE_H
 
-#ifndef linux
 #include <sys/types.h>
 #define __u64 uint64_t
 #define __u32 uint32_t
 #define __s32 int32_t
-#else
-#include <asm/types.h>
-#include <linux/major.h>
-#endif
 
 /** Version number of this interface */
 #define FUSE_KERNEL_VERSION 7
 
 /** Minor version number of this interface */
-#define FUSE_KERNEL_MINOR_VERSION 10
+#define FUSE_KERNEL_MINOR_VERSION 11
 
 /** The node ID of the root inode */
 #define FUSE_ROOT_ID 1
 
-/** The major number of the fuse character device */
-#define FUSE_MAJOR MISC_MAJOR
-
-/** The minor number of the fuse character device */
-#define FUSE_MINOR 229
-
 /* Make sure all structures are padded to 64bit boundary, so 32bit
    userspace works under 64bit kernels */
 
@@ -184,6 +176,21 @@ struct fuse_file_lock {
  */
 #define FUSE_READ_LOCKOWNER	(1 << 1)
 
+/**
+ * Ioctl flags
+ *
+ * FUSE_IOCTL_COMPAT: 32bit compat ioctl on 64bit machine
+ * FUSE_IOCTL_UNRESTRICTED: not restricted to well-formed ioctls, retry allowed
+ * FUSE_IOCTL_RETRY: retry with new iovecs
+ *
+ * FUSE_IOCTL_MAX_IOV: maximum of in_iovecs + out_iovecs
+ */
+#define FUSE_IOCTL_COMPAT	(1 << 0)
+#define FUSE_IOCTL_UNRESTRICTED	(1 << 1)
+#define FUSE_IOCTL_RETRY	(1 << 2)
+
+#define FUSE_IOCTL_MAX_IOV	256
+
 enum fuse_opcode {
 	FUSE_LOOKUP	   = 1,
 	FUSE_FORGET	   = 2,  /* no reply */
@@ -221,6 +228,7 @@ enum fuse_opcode {
 	FUSE_INTERRUPT     = 36,
 	FUSE_BMAP          = 37,
 	FUSE_DESTROY       = 38,
+	FUSE_IOCTL         = 39,
 };
 
 /* The read buffer is required to be at least 8k, but may be much larger */
@@ -421,6 +429,22 @@ struct fuse_bmap_out {
 	__u64	block;
 };
 
+struct fuse_ioctl_in {
+	__u64	fh;
+	__u32	flags;
+	__u32	cmd;
+	__u64	arg;
+	__u32	in_size;
+	__u32	out_size;
+};
+
+struct fuse_ioctl_out {
+	__s32	result;
+	__u32	flags;
+	__u32	in_iovs;
+	__u32	out_iovs;
+};
+
 struct fuse_in_header {
 	__u32	len;
 	__u32	opcode;
diff --git a/include/fuse_lowlevel.h b/include/fuse_lowlevel.h
index 9330548..e17274f 100644
--- a/include/fuse_lowlevel.h
+++ b/include/fuse_lowlevel.h
@@ -807,6 +807,36 @@ struct fuse_lowlevel_ops {
 	 */
 	void (*bmap) (fuse_req_t req, fuse_ino_t ino, size_t blocksize,
 		      uint64_t idx);
+
+	/**
+	 * Ioctl
+	 *
+	 * Note: For unrestricted ioctls (not allowed for FUSE
+	 * servers), data in and out areas can be discovered by giving
+	 * iovs and setting FUSE_IOCTL_RETRY in *@flagsp.  For
+	 * restricted ioctls, kernel prepares in/out data area
+	 * according to the information encoded in @cmd.
+	 *
+	 * Introduced in version 2.9
+	 *
+	 * Valid replies:
+	 *   fuse_reply_ioctl_retry
+	 *   fuse_reply_ioctl
+	 *   fuse_reply_err
+	 *
+	 * @param req request handle
+	 * @param ino the inode number
+	 * @param cmd ioctl command
+	 * @param arg ioctl argument
+	 * @param fi file information
+	 * @param flagsp io/out parameter for FUSE_IOCTL_* flags
+	 * @param in_buf data fetched from the caller
+	 * @param in_size number of fetched bytes
+	 * @param out_size maximum size of output data
+	 */
+	void (*ioctl) (fuse_req_t req, fuse_ino_t ino, int cmd, void *arg,
+		       struct fuse_file_info *fi, unsigned *flagsp,
+		       const void *in_buf, size_t in_bufsz, size_t out_bufszp);
 };
 
 /**
@@ -1022,6 +1052,38 @@ size_t fuse_add_direntry(fuse_req_t req, char *buf, size_t bufsize,
 			 const char *name, const struct stat *stbuf,
 			 off_t off);
 
+/**
+ * Reply to ask for data fetch and output buffer preparation.  ioctl
+ * will be retried with the specified input data fetched and output
+ * buffer prepared.
+ *
+ * Possible requests:
+ *   ioctl
+ *
+ * @param req request handle
+ * @param in_iov iovec specifying data to fetch from the caller
+ * @param in_count number of entries in @in_iov
+ * @param out_iov iovec specifying addresses to write output to
+ * @param out_count number of entries in @out_iov
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_ioctl_retry(fuse_req_t req,
+			   const struct iovec *in_iov, size_t in_count,
+			   const struct iovec *out_iov, size_t out_count);
+
+/**
+ * Reply to finish ioctl
+ *
+ * Possible requests:
+ *   ioctl
+ *
+ * @param req request handle
+ * @param result result to be passed to the caller
+ * @param buf buffer containing output data
+ * @param size length of output data
+ */
+int fuse_reply_ioctl(fuse_req_t req, int result, const void *buf, size_t size);
+
 /* ----------------------------------------------------------- *
  * Utility functions					       *
  * ----------------------------------------------------------- */