[PATCH] Add vector AIO support

This work is initially done by Zach Brown to add support for vectored aio.
These are the core changes for AIO to support
IOCB_CMD_PREADV/IOCB_CMD_PWRITEV.

[akpm@osdl.org: huge build fix]
Signed-off-by: Zach Brown <zach.brown@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Acked-by: Benjamin LaHaise <bcrl@kvack.org>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/linux/aio.h

@@ -7,6 +7,7 @@
 #include <linux/uio.h>
 
 #include <asm/atomic.h>
+#include <linux/uio.h>
 
 #define AIO_MAXSEGS		4
 #define AIO_KIOGRP_NR_ATOMIC	8
@@ -114,6 +115,9 @@ struct kiocb {
 	long			ki_kicked; 	/* just for testing */
 	long			ki_queued; 	/* just for testing */
 	struct iovec		ki_inline_vec;	/* inline vector */
+ 	struct iovec		*ki_iovec;
+ 	unsigned long		ki_nr_segs;
+ 	unsigned long		ki_cur_seg;
 
 	struct list_head	ki_list;	/* the aio core uses this
 						 * for cancellation */

include/linux/aio_abi.h

@@ -41,6 +41,8 @@ enum {
 	 * IOCB_CMD_POLL = 5,
 	 */
 	IOCB_CMD_NOOP = 6,
+	IOCB_CMD_PREADV = 7,
+	IOCB_CMD_PWRITEV = 8,
 };
 
 /* read() from /dev/aio returns these structures. */

include/linux/fs.h

@@ -1150,6 +1150,11 @@ struct inode_operations {
 
 struct seq_file;
 
+ssize_t rw_copy_check_uvector(int type, const struct iovec __user * uvector,
+				unsigned long nr_segs, unsigned long fast_segs,
+				struct iovec *fast_pointer,
+				struct iovec **ret_pointer);
+
 extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *);
 extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *);
 extern ssize_t vfs_readv(struct file *, const struct iovec __user *,