nvme: quieten sparse warning in valid LBA size check

Currently building with C=1 generates the following warning:

  CC      drivers/nvme/host/core.o
  CHECK   drivers/nvme/host/core.c
drivers/nvme/host/core.c:2426:13: warning: unsigned value that used to be signed checked against zero?
drivers/nvme/host/core.c:2426:13: signed value source

This issue was introduced when using check_shl_overflow() to check for
invalid LBA size. Sparse is having trouble dealing with __bitwise __le64
conversion when passing to check_shl_overflow().

Resolve the issue by moving the check_shl_overflow() call to a separate
function, where types are not converted.

The id->lbaf[lbaf].ds < SECTOR_SHIFT check is dropped as
check_shl_overflow() is able to detect negative shifts.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index efaddab8296e0974294fbd28eb8e2ec6d71dc5c8..d37fc70fe48aa46e4ba839cb07a344f2bcdf74ec 100644 (file)
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -2379,6 +2379,11 @@ free:
        return ret;
 }
 
+static bool nvme_invalid_lba_sz(u64 nsze, signed int shift, sector_t *capacity)
+{
+       return check_shl_overflow(nsze, shift, capacity);
+}
+
 static int nvme_update_ns_info_block(struct nvme_ns *ns,
                struct nvme_ns_info *info)
 {
@@ -2422,10 +2427,8 @@ static int nvme_update_ns_info_block(struct nvme_ns *ns,
                        goto out;
        }
 
-       if (id->lbaf[lbaf].ds < SECTOR_SHIFT ||
-           check_shl_overflow(le64_to_cpu(id->nsze),
-                              id->lbaf[lbaf].ds - SECTOR_SHIFT,
-                              &capacity)) {
+       if (nvme_invalid_lba_sz(le64_to_cpu(id->nsze),
+                       id->lbaf[lbaf].ds - SECTOR_SHIFT, &capacity)) {
                dev_warn_once(ns->ctrl->device,
                        "invalid LBA data size %u, skipping namespace\n",
                        id->lbaf[lbaf].ds);