[SCSI] libosd: Fix bug in attr_page handling

The _osd_req_finalize_attr_page was off by a mile, when trying to
append the enc_get_attr segment instead of the proper set_attr segment.

Also properly support when we don't have any attribute to set while
getting a full page. And when clearing an attribute by setting it's
size to zero.

Reported-by: John Chandy <john.chandy@uconn.edu>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

1 files changed, 10 insertions, 6 deletions

diff --git a/drivers/scsi/osd/osd_initiator.c b/drivers/scsi/osd/osd_initiator.c
index e88bbdde49c5..771ab121acc7 100644
--- a/drivers/scsi/osd/osd_initiator.c
+++ b/drivers/scsi/osd/osd_initiator.c
@@ -1218,17 +1218,18 @@ int osd_req_add_get_attr_page(struct osd_request *or,
         or->get_attr.buff = attar_page;
         or->get_attr.total_bytes = max_page_len;
 
-        or->set_attr.buff = set_one_attr->val_ptr;
-        or->set_attr.total_bytes = set_one_attr->len;
-
         cdbh->attrs_page.get_attr_page = cpu_to_be32(page_id);
         cdbh->attrs_page.get_attr_alloc_length = cpu_to_be32(max_page_len);
-        /* ocdb->attrs_page.get_attr_offset; */
+
+        if (!set_one_attr || !set_one_attr->attr_page)
+                return 0; /* The set is optional */
+
+        or->set_attr.buff = set_one_attr->val_ptr;
+        or->set_attr.total_bytes = set_one_attr->len;
 
         cdbh->attrs_page.set_attr_page = cpu_to_be32(set_one_attr->attr_page);
         cdbh->attrs_page.set_attr_id = cpu_to_be32(set_one_attr->attr_id);
         cdbh->attrs_page.set_attr_length = cpu_to_be32(set_one_attr->len);
-        /* ocdb->attrs_page.set_attr_offset; */
         return 0;
 }
 EXPORT_SYMBOL(osd_req_add_get_attr_page);
@@ -1248,11 +1249,14 @@ static int _osd_req_finalize_attr_page(struct osd_request *or)
         if (ret)
                 return ret;
 
+        if (or->set_attr.total_bytes == 0)
+                return 0;
+
         /* set one value */
         cdbh->attrs_page.set_attr_offset =
                 osd_req_encode_offset(or, or->out.total_bytes, &out_padding);
 
-        ret = _req_append_segment(or, out_padding, &or->enc_get_attr, NULL,
+        ret = _req_append_segment(or, out_padding, &or->set_attr, NULL,
                                   &or->out);
         return ret;
 }