xfs: merge xfs_lrw.c into xfs_file.c

Currently the code to implement the file operations is split over
two small files.  Merge the content of xfs_lrw.c into xfs_file.c to
have it in one place.  Note that I haven't done various cleanups
that are possible after this yet, they will follow in the next
patch.  Also the function xfs_dev_is_read_only which was in
xfs_lrw.c before really doesn't fit in here at all and was moved to
xfs_mount.c.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>

fs/xfs/Makefile

@@ -105,7 +105,6 @@ xfs-y				+= $(addprefix $(XFS_LINUX)/, \
 				   xfs_globals.o \
 				   xfs_ioctl.o \
 				   xfs_iops.o \
-				   xfs_lrw.o \
 				   xfs_super.o \
 				   xfs_sync.o \
 				   xfs_xattr.o)

fs/xfs/xfs_mount.c

@@ -2052,6 +2052,26 @@ xfs_mount_log_sb(
 	return error;
 }
 
+/*
+ * If the underlying (data/log/rt) device is readonly, there are some
+ * operations that cannot proceed.
+ */
+int
+xfs_dev_is_read_only(
+	struct xfs_mount	*mp,
+	char			*message)
+{
+	if (xfs_readonly_buftarg(mp->m_ddev_targp) ||
+	    xfs_readonly_buftarg(mp->m_logdev_targp) ||
+	    (mp->m_rtdev_targp && xfs_readonly_buftarg(mp->m_rtdev_targp))) {
+		cmn_err(CE_NOTE,
+			"XFS: %s required on read-only device.", message);
+		cmn_err(CE_NOTE,
+			"XFS: write access unavailable, cannot proceed.");
+		return EROFS;
+	}
+	return 0;
+}
 
 #ifdef HAVE_PERCPU_SB
 /*

fs/xfs/xfs_vnodeops.h

@@ -50,18 +50,6 @@ int xfs_attr_set(struct xfs_inode *dp, const unsigned char *name,
 int xfs_attr_remove(struct xfs_inode *dp, const unsigned char *name, int flags);
 int xfs_attr_list(struct xfs_inode *dp, char *buffer, int bufsize,
 		int flags, struct attrlist_cursor_kern *cursor);
-ssize_t xfs_read(struct xfs_inode *ip, struct kiocb *iocb,
-		const struct iovec *iovp, unsigned int segs,
-		loff_t *offset, int ioflags);
-ssize_t xfs_splice_read(struct xfs_inode *ip, struct file *infilp,
-		loff_t *ppos, struct pipe_inode_info *pipe, size_t count,
-		int flags, int ioflags);
-ssize_t xfs_splice_write(struct xfs_inode *ip,
-		struct pipe_inode_info *pipe, struct file *outfilp,
-		loff_t *ppos, size_t count, int flags, int ioflags);
-ssize_t xfs_write(struct xfs_inode *xip, struct kiocb *iocb,
-		const struct iovec *iovp, unsigned int nsegs,
-		loff_t *offset, int ioflags);
 int xfs_bmap(struct xfs_inode *ip, xfs_off_t offset, ssize_t count,
 		int flags, struct xfs_iomap *iomapp, int *niomaps);
 void xfs_tosspages(struct xfs_inode *inode, xfs_off_t first,