Re: [build fix] Re: [GIT PATCH] SCSI part 1

[Ingo Molnar <mingo@elte.hu>]

* Ingo Molnar <mingo@elte.hu> wrote:

> > scsi_cmnd.h depends on symbols defined in blkdev.h. The fix is to 
> > include blkdev.h as well.
> 
> that wont work - a better replacement fix is the one below. The 
> problem is that scsi.h is included even on !CONFIG_BLOCK and then the 
> BLK_MAX_CDB symbol is meaningless.

-v3 .. the new methods need to be under #ifdef CONFIG_BLOCK as well. 
Note my patch is just a quick RFC, this can probably be done cleaner.

	Ingo

------------->
commit 21a6d82fe95eced3775fb45ac46102b872db02e5
Author: Ingo Molnar <mingo@elte.hu>
Date:   Wed Jul 16 11:56:08 2008 +0200

    scsi: fix build error in fs/compat_ioctl.c
    
    -tip testing found that the build broke in fs/compat_ioctl.c:
    
    ----------->
    In file included from include/scsi/scsi.h:12,
                     from fs/compat_ioctl.c:72:
    include/scsi/scsi_cmnd.h:27:25: warning: "BLK_MAX_CDB" is not defined
    include/scsi/scsi_cmnd.h:28:3: error: #error MAX_COMMAND_SIZE can not be bigger than BLK_MAX_CDB
    In file included from include/scsi/scsi.h:12,
                     from fs/compat_ioctl.c:72:
    include/scsi/scsi_cmnd.h: In function ‘scsi_bidi_cmnd’:
    include/scsi/scsi_cmnd.h:182: error: implicit declaration of function ‘blk_bidi_rq’
    include/scsi/scsi_cmnd.h:183: error: dereferencing pointer to incomplete type
    include/scsi/scsi_cmnd.h: In function ‘scsi_in’:
    include/scsi/scsi_cmnd.h:189: error: dereferencing pointer to incomplete type
    <-----------
    
    with this config:
    
      http://redhat.com/~mingo/misc/config-Wed_Jul_16_11_32_32_CEST_2008.bad
    
    I have bisected it down to:
    
    | feac6a07c4a3578bffd6769bb4927e8a7e1f3ffe is first bad commit
    | commit feac6a07c4a3578bffd6769bb4927e8a7e1f3ffe
    | Author: Martin Petermann <martin@linux.vnet.ibm.com>
    | Date:   Wed Jul 2 10:56:35 2008 +0200
    |
    |    [SCSI] zfcp: Move status accessors from zfcp to SCSI include file.
    |
    |    Move the accessor functions for the scsi_cmnd status from zfcp to the
    |    SCSI include file. Change the interface to the functions to pass the
    |    scsi_cmnd pointer instead of the status pointer.
    |
    |    Signed-off-by: Martin Petermann <martin@linux.vnet.ibm.com>
    |    Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
    |    Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
    
    The problem is due to this aspect of that change:
    
    | @@ -9,6 +9,7 @@
    |  #define _SCSI_SCSI_H
    |
    |  #include <linux/types.h>
    | +#include <scsi/scsi_cmnd.h>
    |
    |  /*
    |   * The maximum number of SG segments that we will put inside a
    
    scsi_cmnd.h depends on symbols defined in blkdev.h but those symbols
    are not available if !CONFIG_BLOCK.
    
    Only include scsi/scsi_cmnd.h if on CONFIG_BLOCK.
    (those methods are not used when CONFIG_BLOCK is off anyway).
    
    Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 include/scsi/scsi.h |    8 ++++++--
 1 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/include/scsi/scsi.h b/include/scsi/scsi.h
index 00137a7..0df6c05 100644
--- a/include/scsi/scsi.h
+++ b/include/scsi/scsi.h
@@ -9,7 +9,10 @@
 #define _SCSI_SCSI_H
 
 #include <linux/types.h>
-#include <scsi/scsi_cmnd.h>
+
+#ifdef CONFIG_BLOCK
+# include <scsi/scsi_cmnd.h>
+#endif
 
 /*
  * The maximum number of SG segments that we will put inside a
@@ -426,6 +429,7 @@ struct scsi_lun {
 #define driver_byte(result) (((result) >> 24) & 0xff)
 #define suggestion(result)  (driver_byte(result) & SUGGEST_MASK)
 
+#ifdef CONFIG_BLOCK
 static inline void set_msg_byte(struct scsi_cmnd *cmd, char status)
 {
 	cmd->result |= status << 8;
@@ -440,7 +444,7 @@ static inline void set_driver_byte(struct scsi_cmnd *cmd, char status)
 {
 	cmd->result |= status << 24;
 }
-
+#endif
 
 #define sense_class(sense)  (((sense) >> 4) & 0x7)
 #define sense_error(sense)  ((sense) & 0xf)