Minor diff reduction with ZoF in include/sys

- move linux/ includes to platform headers
- add void * io_bio to zio for tracking the underlying bio
- add freebsd specific fields to abd_scatter

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Kjeld Schouten <kjeld@schouten-lebbing.nl>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Closes #9615

include/os/linux/spl/sys/uio.h

@@ -26,8 +26,12 @@
 #ifndef _SPL_UIO_H
 #define	_SPL_UIO_H
 
+#include <sys/debug.h>
 #include <linux/uio.h>
 #include <linux/blkdev.h>
+#include <linux/blkdev_compat.h>
+#include <linux/mm.h>
+#include <linux/bio.h>
 #include <asm/uaccess.h>
 #include <sys/types.h>
 

include/sys/abd.h

@@ -29,11 +29,7 @@
 #include <sys/isa_defs.h>
 #include <sys/debug.h>
 #include <sys/refcount.h>
-#ifdef _KERNEL
-#include <linux/mm.h>
-#include <linux/bio.h>
 #include <sys/uio.h>
-#endif
 
 #ifdef __cplusplus
 extern "C" {
@@ -56,8 +52,13 @@ typedef struct abd {
 	union {
 		struct abd_scatter {
 			uint_t		abd_offset;
+#if defined(__FreeBSD__) && defined(_KERNEL)
+			uint_t  abd_chunk_size;
+			void    *abd_chunks[];
+#else
 			uint_t		abd_nents;
 			struct scatterlist *abd_sgl;
+#endif
 		} abd_scatter;
 		struct abd_linear {
 			void		*abd_buf;

include/sys/dmu.h

@@ -847,7 +847,6 @@ void dmu_write_by_dnode(dnode_t *dn, uint64_t offset, uint64_t size,
 void dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
 	dmu_tx_t *tx);
 #ifdef _KERNEL
-#include <linux/blkdev_compat.h>
 int dmu_read_uio(objset_t *os, uint64_t object, struct uio *uio, uint64_t size);
 int dmu_read_uio_dbuf(dmu_buf_t *zdb, struct uio *uio, uint64_t size);
 int dmu_read_uio_dnode(dnode_t *dn, struct uio *uio, uint64_t size);

include/sys/zfs_project.h

@@ -32,7 +32,7 @@
 #endif
 #endif
 
-#include <linux/fs.h>
+#include <sys/vfs.h>
 
 #ifdef FS_PROJINHERIT_FL
 #define	ZFS_PROJINHERIT_FL	FS_PROJINHERIT_FL

include/sys/zio.h

@@ -500,6 +500,7 @@ struct zio {
 	zio_gang_node_t	*io_gang_tree;
 	void		*io_executor;
 	void		*io_waiter;
+	void		*io_bio;
 	kmutex_t	io_lock;
 	kcondvar_t	io_cv;
 	int		io_allocator;