lib: scatterlist: move SG pool code from SCSI driver to lib/sg_pool.c

Now it's ready to move the mempool based SG chained allocator code from
SCSI driver to lib/sg_pool.c, which will be compiled only based on a Kconfig
symbol CONFIG_SG_POOL.

SCSI selects CONFIG_SG_POOL.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/lib/Kconfig b/lib/Kconfig
index 3cca1222578e..61d55bd0ed89 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -523,6 +523,13 @@ config SG_SPLIT
          a scatterlist. This should be selected by a driver or an API which
          whishes to split a scatterlist amongst multiple DMA channels.
 
+config SG_POOL
+        def_bool n
+        help
+         Provides a helper to allocate chained scatterlists. This should be
+         selected by a driver or an API which whishes to allocate chained
+         scatterlist.
+
 #
 # sg chaining option
 #