nvmet: fix per feat data len for get_feature

The existing implementation for the get_feature admin-cmd does not
use per-feature data len. This patch introduces a new helper function
nvmet_feat_data_len(), which is used to calculate per feature data len.
Right now we only set data len for fid 0x81 (NVME_FEAT_HOST_ID).

Fixes: commit e9061c397839 ("nvmet: Remove the data_len field from the nvmet_req struct")

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Amit Engel <amit.engel@dell.com>
[endiness, naming, and kernel style fixes]
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
index 56c21b5..72a7e41 100644 (file)
--- a/drivers/nvme/target/admin-cmd.c
+++ b/drivers/nvme/target/admin-cmd.c
@@ -24,6 +24,16 @@ u32 nvmet_get_log_page_len(struct nvme_command *cmd)
        return len;
 }
 
+static u32 nvmet_feat_data_len(struct nvmet_req *req, u32 cdw10)
+{
+       switch (cdw10 & 0xff) {
+       case NVME_FEAT_HOST_ID:
+               return sizeof(req->sq->ctrl->hostid);
+       default:
+               return 0;
+       }
+}
+
 u64 nvmet_get_log_page_offset(struct nvme_command *cmd)
 {
        return le64_to_cpu(cmd->get_log_page.lpo);
@@ -778,7 +788,7 @@ static void nvmet_execute_get_features(struct nvmet_req *req)
        u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
        u16 status = 0;
 
-       if (!nvmet_check_data_len(req, 0))
+       if (!nvmet_check_data_len(req, nvmet_feat_data_len(req, cdw10)))
                return;
 
        switch (cdw10 & 0xff) {