[XFS] Add sendfile support

SGI Modid: 2.5.x-xfs:slinx:132980a

fs/xfs/linux/xfs_file.c

@@ -138,6 +138,22 @@ linvfs_aio_write(
 	return linvfs_writev(iocb->ki_filp, &iov, 1, &iocb->ki_pos);
 }
 
+STATIC ssize_t
+linvfs_sendfile(
+	struct file		*filp,
+	loff_t			*ppos,
+	size_t			count,
+	read_actor_t		actor,
+	void			*target)
+{
+	vnode_t			*vp = LINVFS_GET_VP(filp->f_dentry->d_inode);
+	int			error;
+
+	VOP_SENDFILE(vp, filp, ppos, count, actor, target, NULL, error);
+
+	return error;
+}
+
 
 STATIC int
 linvfs_open(
@@ -348,6 +364,7 @@ struct file_operations linvfs_file_operations = {
 	.writev		= linvfs_writev,
 	.aio_read	= linvfs_aio_read,
 	.aio_write	= linvfs_aio_write,
+	.sendfile	= linvfs_sendfile,
 	.ioctl		= linvfs_ioctl,
 	.mmap		= linvfs_file_mmap,
 	.open		= linvfs_open,

fs/xfs/linux/xfs_lrw.c

@@ -205,6 +205,67 @@ xfs_read(
 	return ret;
 }
 
+ssize_t
+xfs_sendfile(
+	bhv_desc_t		*bdp,
+	struct file		*filp,
+	loff_t			*offp,
+	size_t			count,
+	read_actor_t		actor,
+	void			*target,
+	cred_t			*credp)
+{
+	size_t			size = 0;
+	ssize_t			ret;
+	xfs_fsize_t		n;
+	xfs_inode_t		*ip;
+	xfs_mount_t		*mp;
+	vnode_t			*vp;
+
+	ip = XFS_BHVTOI(bdp);
+	vp = BHV_TO_VNODE(bdp);
+	mp = ip->i_mount;
+	vn_trace_entry(vp, "xfs_sendfile", (inst_t *)__return_address);
+
+	XFS_STATS_INC(xfsstats.xs_read_calls);
+
+	n = XFS_MAX_FILE_OFFSET - *offp;
+	if ((n <= 0) || (size == 0))
+		return 0;
+
+	if (n < size)
+		size = n;
+
+	if (XFS_FORCED_SHUTDOWN(mp)) {
+		return -EIO;
+	}
+
+	xfs_ilock(ip, XFS_IOLOCK_SHARED);
+
+	if (DM_EVENT_ENABLED(vp->v_vfsp, ip, DM_EVENT_READ) &&
+	    !(filp->f_mode & FINVIS)) {
+		int error;
+		vrwlock_t locktype = VRWLOCK_READ;
+
+		error = xfs_dm_send_data_event(DM_EVENT_READ, bdp, *offp,
+				size, FILP_DELAY_FLAG(filp), &locktype);
+		if (error) {
+			xfs_iunlock(ip, XFS_IOLOCK_SHARED);
+			return -error;
+		}
+	}
+
+	ret = generic_file_sendfile(filp, offp, count, actor, target);
+	xfs_iunlock(ip, XFS_IOLOCK_SHARED);
+
+	XFS_STATS_ADD(xfsstats.xs_read_bytes, ret);
+
+	if (!(filp->f_mode & FINVIS))
+		xfs_ichgtime(ip, XFS_ICHGTIME_ACC);
+
+	return ret;
+}
+
 /*
  * This routine is called to handle zeroing any space in the last
  * block of the file that is beyond the EOF.  We do this since the

fs/xfs/linux/xfs_vnode.h

@@ -180,6 +180,9 @@ typedef ssize_t (*vop_read_t)(bhv_desc_t *, struct file *,
 typedef ssize_t (*vop_write_t)(bhv_desc_t *, struct file *,
 				const struct iovec *, unsigned long,
 				loff_t *, struct cred *);
+typedef ssize_t (*vop_sendfile_t)(bhv_desc_t *, struct file *,
+				loff_t *, size_t, read_actor_t,
+				void *, struct cred *);
 typedef int	(*vop_ioctl_t)(bhv_desc_t *, struct inode *, struct file *, unsigned int, unsigned long);
 typedef int	(*vop_getattr_t)(bhv_desc_t *, struct vattr *, int,
 				struct cred *);
@@ -232,6 +235,7 @@ typedef struct vnodeops {
 	vop_open_t		vop_open;
 	vop_read_t		vop_read;
 	vop_write_t		vop_write;
+	vop_sendfile_t		vop_sendfile;
 	vop_ioctl_t		vop_ioctl;
 	vop_getattr_t		vop_getattr;
 	vop_setattr_t		vop_setattr;
@@ -283,6 +287,12 @@ typedef struct vnodeops {
 	rv = _VOP_(vop_write, vp)((vp)->v_fbhv,file,iov,segs,offset,cr);\
 	VN_BHV_READ_UNLOCK(&(vp)->v_bh);				\
 }
+#define VOP_SENDFILE(vp,f,of,cnt,act,targ,cr,rv)			\
+{									\
+	VN_BHV_READ_LOCK(&(vp)->v_bh);					\
+	rv = _VOP_(vop_sendfile, vp)((vp)->v_fbhv,f,of,cnt,act,targ,cr);\
+	VN_BHV_READ_UNLOCK(&(vp)->v_bh);				\
+}
 #define VOP_BMAP(vp,of,sz,rw,b,n,rv)					\
 {									\
 	VN_BHV_READ_LOCK(&(vp)->v_bh);					\