[RFC PATCH 05/11] hw/nvme: remove assert from nvme_get_zone_by_slba

[Klaus Jensen <its@irrelevant.dk>]

From: Klaus Jensen <k.jensen@samsung.com>

Make nvme_get_zone_by_slba() return NULL if the slba is out of range.
This allows the function to be used without guarding the call with a
call to nvme_check_bounds(), in preparation for the next patch.

Add asserts after calling nvme_get_zone_by_slba() instead.

Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
---
 hw/nvme/ctrl.c | 18 ++++++++++++++----
 1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/hw/nvme/ctrl.c b/hw/nvme/ctrl.c
index 0dc86f7b603c..0895faaa0724 100644
--- a/hw/nvme/ctrl.c
+++ b/hw/nvme/ctrl.c
@@ -1536,7 +1536,10 @@ static inline NvmeZone *nvme_get_zone_by_slba(NvmeNamespace *ns, uint64_t slba)
 {
     uint32_t zone_idx = nvme_zone_idx(ns, slba);
 
-    assert(zone_idx < ns->num_zones);
+    if (zone_idx >= ns->num_zones) {
+        return NULL;
+    }
+
     return &ns->zone_array[zone_idx];
 }
 
@@ -1613,11 +1616,16 @@ static uint16_t nvme_check_zone_state_for_read(NvmeZone *zone)
 static uint16_t nvme_check_zone_read(NvmeNamespace *ns, uint64_t slba,
                                      uint32_t nlb)
 {
-    NvmeZone *zone = nvme_get_zone_by_slba(ns, slba);
-    uint64_t bndry = nvme_zone_rd_boundary(ns, zone);
-    uint64_t end = slba + nlb;
+    NvmeZone *zone;
+    uint64_t bndry, end;
     uint16_t status;
 
+    zone = nvme_get_zone_by_slba(ns, slba);
+    assert(zone);
+
+    bndry = nvme_zone_rd_boundary(ns, zone);
+    end = slba + nlb;
+
     status = nvme_check_zone_state_for_read(zone);
     if (status) {
         ;
@@ -1780,6 +1788,7 @@ static void nvme_finalize_zoned_write(NvmeNamespace *ns, NvmeRequest *req)
     slba = le64_to_cpu(rw->slba);
     nlb = le16_to_cpu(rw->nlb) + 1;
     zone = nvme_get_zone_by_slba(ns, slba);
+    assert(zone);
 
     nvme_advance_zone_wp(ns, zone, nlb);
 }
@@ -3175,6 +3184,7 @@ static uint16_t nvme_do_write(NvmeCtrl *n, NvmeRequest *req, bool append,
 
     if (ns->params.zoned) {
         zone = nvme_get_zone_by_slba(ns, slba);
+        assert(zone);
 
         if (append) {
             bool piremap = !!(ctrl & NVME_RW_PIREMAP);
-- 
2.31.1