[PATCH 4.18 061/235] nvmet: fix file discard return status

[Greg Kroah-Hartman]

4.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Sagi Grimberg <s...@grimberg.me>

[ Upstream commit 1b72b71faccee986e2128a271125177dfe91f7b7 ]

If nvmet_copy_from_sgl failed, we falsly return successful
completion status.

Fixes: d5eff33ee6f8 ("nvmet: add simple file backed ns support")
Signed-off-by: Sagi Grimberg <s...@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulka...@wdc.com>
Signed-off-by: Christoph Hellwig <h...@lst.de>
Signed-off-by: Sasha Levin <alexander.le...@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 drivers/nvme/target/io-cmd-file.c |   18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

--- a/drivers/nvme/target/io-cmd-file.c
+++ b/drivers/nvme/target/io-cmd-file.c
@@ -209,22 +209,24 @@ static void nvmet_file_execute_discard(s
 {
        int mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE;
        struct nvme_dsm_range range;
-       loff_t offset;
-       loff_t len;
-       int i, ret;
+       loff_t offset, len;
+       u16 ret;
+       int i;
 
        for (i = 0; i <= le32_to_cpu(req->cmd->dsm.nr); i++) {
-               if (nvmet_copy_from_sgl(req, i * sizeof(range), &range,
-                                       sizeof(range)))
+               ret = nvmet_copy_from_sgl(req, i * sizeof(range), &range,
+                                       sizeof(range));
+               if (ret)
                        break;
                offset = le64_to_cpu(range.slba) << req->ns->blksize_shift;
                len = le32_to_cpu(range.nlb) << req->ns->blksize_shift;
-               ret = vfs_fallocate(req->ns->file, mode, offset, len);
-               if (ret)
+               if (vfs_fallocate(req->ns->file, mode, offset, len)) {
+                       ret = NVME_SC_INTERNAL | NVME_SC_DNR;
                        break;
+               }
        }
 
-       nvmet_req_complete(req, ret < 0 ? NVME_SC_INTERNAL | NVME_SC_DNR : 0);
+       nvmet_req_complete(req, ret);
 }
 
 static void nvmet_file_dsm_work(struct work_struct *w)