[PATCH v3] storvsc: use small sg_tablesize on x86

From: Olaf Hering
Date: Thu Jun 09 2016 - 12:26:16 EST


Reducing the sg_tablesize allows booting of 32bit kernels in VMs, after
commit be0cf6ca301c61458dc4aa1a37acf4f58d2ed3d6 ("scsi: storvsc: Set the
tablesize based on the information given by the host")

[ 5.567138] hv_storvsc vmbus_1: adjusting sg_tablesize 0x800 -> 0x20

Signed-off-by: Olaf Hering <olaf@xxxxxxxxx>
---

As requested, use CONFIG_<bitsize>. For some reason IS_ENABLED(64_BIT)
does not work.

drivers/scsi/storvsc_drv.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c
index 3ddcabb..ae42324 100644
--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1673,11 +1673,15 @@ static int storvsc_probe(struct hv_device *device,
/* max cmd length */
host->max_cmd_len = STORVSC_MAX_CMD_LEN;

+#ifdef CONFIG_64BIT
/*
* set the table size based on the info we got
* from the host.
*/
host->sg_tablesize = (stor_device->max_transfer_bytes >> PAGE_SHIFT);
+#else
+ host->sg_tablesize = MAX_MULTIPAGE_BUFFER_COUNT;
+#endif

/* Register the HBA and start the scsi bus scan */
ret = scsi_add_host(host, &device->device);