xprtrdma: Fix DMAR failure in frwr_op_map() after reconnect

When a LOCALINV WR is flushed, the frmr is marked STALE, then
frwr_op_unmap_sync DMA-unmaps the frmr's SGL. These STALE frmrs
are then recovered when frwr_op_map hunts for an INVALID frmr to
use.

All other cases that need frmr recovery leave that SGL DMA-mapped.
The FRMR recovery path unconditionally DMA-unmaps the frmr's SGL.

To avoid DMA unmapping the SGL twice for flushed LOCAL_INV WRs,
alter the recovery logic (rather than the hot frwr_op_unmap_sync
path) to distinguish among these cases. This solution also takes
care of the case where multiple LOCAL_INV WRs are issued for the
same rpcrdma_req, some complete successfully, but some are flushed.

Reported-by: Vasco Steinmetz <linux@kyberraum.net>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Vasco Steinmetz <linux@kyberraum.net>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

path: root/include/uapi/asm-generic/param.h

#ifndef _UAPI__ASM_GENERIC_PARAM_H
#define _UAPI__ASM_GENERIC_PARAM_H

#ifndef HZ
#define HZ 100
#endif

#ifndef EXEC_PAGESIZE
#define EXEC_PAGESIZE	4096
#endif

#ifndef NOGROUP
#define NOGROUP		(-1)
#endif

#define MAXHOSTNAMELEN	64	/* max length of hostname */


#endif /* _UAPI__ASM_GENERIC_PARAM_H */