diff options
author | Christoph Hellwig <hch@lst.de> | 2014-04-15 14:38:31 +0200 |
---|---|---|
committer | Christoph Hellwig <hch@lst.de> | 2014-07-25 17:16:21 -0400 |
commit | c53c6d6a68b13b1dff2892551b56cfdc07887d9e (patch) | |
tree | 8bd6ddc1ff0f33e357ad6c230f62fd7b1cf1b28a /include/scsi/scsi_host.h | |
parent | f6d47e74fcb2814225e429c94355ad1c551daffb (diff) |
scatterlist: allow chaining to preallocated chunks
Blk-mq drivers usually preallocate their S/G list as part of the request,
but if we want to support the very large S/G lists currently supported by
the SCSI code that would tie up a lot of memory in the preallocated request
pool. Add support to the scatterlist code so that it can initialize a
S/G list that uses a preallocated first chunks and dynamically allocated
additional chunks. That way the scsi-mq code can preallocate a first
page worth of S/G entries as part of the request, and dynamically extend
the S/G list when needed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Webb Scales <webbnh@hp.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Tested-by: Bart Van Assche <bvanassche@acm.org>
Tested-by: Robert Elliott <elliott@hp.com>
Diffstat (limited to 'include/scsi/scsi_host.h')
0 files changed, 0 insertions, 0 deletions