scsifront_action_handler() will deadlock on host->host_lock, if the
ring is full and it has to wait for entries to become available.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
This function is only called with a spin_lock held and IRQs disabled.
The allocation is not allowed to sleep and NOIO is not sufficient, it
has to be ATOMIC.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Introduces the Xen pvSCSI frontend. With pvSCSI it is possible for a
Xen domU to issue SCSI commands to a SCSI LUN assigned to that
domU. The SCSI commands are passed to the pvSCSI backend in a driver
domain (usually Dom0) which is owner of the physical device. This
allows e.g. to use SCSI tape drives in a Xen domU.
The code is taken from the pvSCSI implementation in Xen done by
Fujitsu based on Linux kernel 2.6.18.
Changes from the original version are:
- port to upstream kernel
- put all code in just one source file
- move module to appropriate location in kernel tree
- adapt to Linux style guide
- some minor code simplifications
- replace constants with defines
- remove not used defines
- add support for larger SG lists by putting them in a granted page
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
David Vrabel