From a89bcc465bb9d093ca0b05a5bd034017dd6b25ad Mon Sep 17 00:00:00 2001
From: Ben Gras <ben@minix3.org>
Date: Mon, 21 Jun 2010 18:25:04 +0000
Subject: [PATCH] mfs: minor cleanup of readahead: they can be private to
 read.c.

---
 servers/mfs/glo.h  |  3 ---
 servers/mfs/main.c |  2 +-
 servers/mfs/read.c | 10 ++++++++--
 3 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/servers/mfs/glo.h b/servers/mfs/glo.h
index 24f281b35..1cfb0355f 100644
--- a/servers/mfs/glo.h
+++ b/servers/mfs/glo.h
@@ -9,9 +9,6 @@
 
 #include <minix/vfsif.h>
 
-EXTERN off_t rdahedpos;		/* position to read ahead */
-EXTERN struct inode *rdahed_inode;	/* pointer to inode to read ahead */
-
 /* The following variables are used for returning results to the caller. */
 EXTERN int err_code;		/* temporary storage for error number */
 EXTERN int rdwt_err;		/* status of last disk i/o request */
diff --git a/servers/mfs/main.c b/servers/mfs/main.c
index 1f8435679..61ed8dc7f 100644
--- a/servers/mfs/main.c
+++ b/servers/mfs/main.c
@@ -67,7 +67,7 @@ PUBLIC int main(int argc, char *argv[])
 	fs_m_out.m_type = error; 
 	reply(src, &fs_m_out);
 
-	if (error == OK && rdahed_inode != NULL) 
+	if (error == OK) 
 		read_ahead(); /* do block read ahead */
       
   }
diff --git a/servers/mfs/read.c b/servers/mfs/read.c
index 900502f2a..56b129c1e 100644
--- a/servers/mfs/read.c
+++ b/servers/mfs/read.c
@@ -20,6 +20,9 @@ FORWARD _PROTOTYPE( int rw_chunk, (struct inode *rip, u64_t position,
 
 PRIVATE char getdents_buf[GETDENTS_BUFSIZ];
 
+PRIVATE off_t rdahedpos;         /* position to read ahead */
+PRIVATE struct inode *rdahed_inode;      /* pointer to inode to read ahead */
+
 /*===========================================================================*
  *				fs_readwrite				     *
  *===========================================================================*/
@@ -61,7 +64,7 @@ PUBLIC int fs_readwrite(void)
   nrbytes = (size_t) fs_m_in.REQ_NBYTES;
   
   rdwt_err = OK;		/* set to EIO if disk error occurs */
-  
+
   if (rw_flag == WRITING && !block_spec) {
 	  /* Check in advance to see if file will grow too big. */
 	  if (position > (off_t) (rip->i_sp->s_max_size - nrbytes))
@@ -115,7 +118,7 @@ PUBLIC int fs_readwrite(void)
      (regular || mode_word == I_DIRECTORY)) {
 	  rdahed_inode = rip;
 	  rdahedpos = position;
-  }
+  } 
 
   rip->i_seek = NO_SEEK;
 
@@ -401,6 +404,9 @@ PUBLIC void read_ahead()
   struct buf *bp;
   block_t b;
 
+  if(!rdahed_inode)
+	return;
+
   rip = rdahed_inode;		/* pointer to inode to read ahead from */
   block_size = get_block_size(rip->i_dev);
   rdahed_inode = NULL;	/* turn off read ahead */