From: Ming Lei Date: Tue, 18 Jun 2019 01:37:54 +0000 (+0800) Subject: scsi: pcmcia: nsp_cs: use sg helper to iterate over scatterlist X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=1b3a4640106603ce6b3ad261ef4d20ea60e9790b;p=openwrt%2Fstaging%2Fblogic.git scsi: pcmcia: nsp_cs: use sg helper to iterate over scatterlist Unlike the legacy I/O path, scsi-mq preallocates a large array to hold the scatterlist for each request. This static allocation can consume substantial amounts of memory on modern controllers which support a large number of concurrently outstanding requests. To facilitate a switch to a smaller static allocation combined with a dynamic allocation for requests that need it, we need to make sure all SCSI drivers handle chained scatterlists correctly. Convert remaining drivers that directly dereference the scatterlist array to using the iterator functions. [mkp: clarified commit message] Reviewed-by: Christoph Hellwig Reviewed-by: Bart Van Assche Signed-off-by: Ming Lei Signed-off-by: Martin K. Petersen --- diff --git a/drivers/scsi/pcmcia/nsp_cs.c b/drivers/scsi/pcmcia/nsp_cs.c index a81748e6e8fb..97416e1dcc5b 100644 --- a/drivers/scsi/pcmcia/nsp_cs.c +++ b/drivers/scsi/pcmcia/nsp_cs.c @@ -789,7 +789,7 @@ static void nsp_pio_read(struct scsi_cmnd *SCpnt) SCpnt->SCp.buffers_residual != 0 ) { //nsp_dbg(NSP_DEBUG_DATA_IO, "scatterlist next timeout=%d", time_out); SCpnt->SCp.buffers_residual--; - SCpnt->SCp.buffer++; + SCpnt->SCp.buffer = sg_next(SCpnt->SCp.buffer); SCpnt->SCp.ptr = BUFFER_ADDR; SCpnt->SCp.this_residual = SCpnt->SCp.buffer->length; time_out = 1000; @@ -887,7 +887,7 @@ static void nsp_pio_write(struct scsi_cmnd *SCpnt) SCpnt->SCp.buffers_residual != 0 ) { //nsp_dbg(NSP_DEBUG_DATA_IO, "scatterlist next"); SCpnt->SCp.buffers_residual--; - SCpnt->SCp.buffer++; + SCpnt->SCp.buffer = sg_next(SCpnt->SCp.buffer); SCpnt->SCp.ptr = BUFFER_ADDR; SCpnt->SCp.this_residual = SCpnt->SCp.buffer->length; time_out = 1000;