UML - Limit request size on COWed devices
PATCH 2/3 UML - Limit request size on COWed devices
COWed devices can't handle more than 32 (64 on x86_64) sectors in one request due to the size of the bitmap being carried around in the io_thread_req.
Enforce that by telling the block layer not to put too many sectors in requests to COWed devices.
--
arch/um/drivers/ubd_kern.c | 2 ++ 1 file changed, 2 insertions(+)
arch/um/drivers/ubd_kern.c +2 -0
@@ -712,6 +712,8 @@ static int ubd_add(int n, char **error_o ubd_dev->queue->queuedata = ubd_dev;blk_queue_max_hw_segments (ubd_dev->queue,MAX_SG ); +if (ubd_dev->cow.file !=NULL ) +blk_queue_max_sectors (ubd_dev->queue,8 *sizeof (long )); err =ubd_disk_register (MAJOR_NR , ubd_dev->size, n, &ubd_gendisk[n]);if (err){ *error_out ="Failed to register device" ;
-------------------------------------------------------------------------
This SF.net email is sponsored by DB2 Express
Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now.
http://sourceforge.net/powerbar/db2/
_______________________________________________
User-mode-linux-devel mailing list [email protected]
https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel
On 13 Jul 2007, Jeff Dike uttered the following:
Quoted 3 lines
COWed devices can't handle more than 32 (64 on
x86_64) sectors in one request due to the size of the bitmap being carried around in theio_thread_req.
This feels like a -stable candidate to me.
-------------------------------------------------------------------------
This SF.net email is sponsored by DB2 Express
Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now.
http://sourceforge.net/powerbar/db2/
_______________________________________________
User-mode-linux-devel mailing list [email protected]
https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel
Quoted 1 line · Nix
This feels like a -stable candidate to me.
Right you are - that's the first place I sent it.
Jeff
Signature · 11 lines
Work email - jdike at linux dot intel dot com ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ User-mode-linux-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel
On 13 Jul 2007, Jeff Dike outgrape:
Quoted 4 lines · Nix
Quoted 1 line
This feels like a -stable candidate to me.
Right you are - that's the first place I sent it.
Ah. So, first I report a bug two days *after* you post a fix, and then I recommend you send it somewhere you've already sent it.
I think I need to go and dig a hole and crawl inside for a while. :/
-------------------------------------------------------------------------
This SF.net email is sponsored by DB2 Express
Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now.
http://sourceforge.net/powerbar/db2/
_______________________________________________
User-mode-linux-devel mailing list [email protected]
https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel