ensure vdev_stat struct layout compat betweem 2.1 and 2.2

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>

diff --git a/debian/patches/0014-zpool-status-tighten-bounds-for-noalloc-stat-availab.patch b/debian/patches/0014-zpool-status-tighten-bounds-for-noalloc-stat-availab.patch
new file mode 100644 (file)
index 0000000..f58c58e
--- /dev/null
+++ b/debian/patches/0014-zpool-status-tighten-bounds-for-noalloc-stat-availab.patch
@@ -0,0 +1,66 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Thomas Lamprecht <t.lamprecht@proxmox.com>
+Date: Sun, 12 Nov 2023 15:52:25 +0100
+Subject: [PATCH] zpool status: tighten bounds for noalloc stat availabillity
+
+When running zfs 2.2.0 userspace utilities with a kernel that still
+has 2.1.13 modules zpool status adds `(non-allocating)` next to the
+disk name of a single-disk pool.
+
+The reason for this seems to be that the patch adding the `vs_pspace` field was
+backported, but the one adding `vs_noalloc` was not.
+
+Itself that is not a problem, but in 2.2 `noalloc` was added before `psspace`,
+so the struct layout between 2.1.13 and 2.2.0 do NOT match anymore...
+
+I.e., the struct looks like the following at the end for ZFS 2.1.x:
+
+```
+typedef struct vdev_stat {
+    hrtime_t        vs_timestamp;           /* time since vdev load */
+    // snip
+    uint64_t        vs_logical_ashift;      /* vdev_logical_ashift  */
+    uint64_t        vs_physical_ashift;     /* vdev_physical_ashift */
+    uint64_t        vs_pspace;              /* physical capacity */
+} vdev_stat_t;
+```
+
+And like the following on ZFS 2.2.x:
+```
+typedef struct vdev_stat {
+    hrtime_t        vs_timestamp;           /* time since vdev load */
+    // snip
+    uint64_t        vs_logical_ashift;      /* vdev_logical_ashift  */
+    uint64_t        vs_physical_ashift;     /* vdev_physical_ashift */
+    uint64_t        vs_noalloc;             /* allocations halted?  */
+    uint64_t        vs_pspace;              /* physical capacity */
+} vdev_stat_t;
+```
+
+Resulting in 2.2.x user-space tooling interpreting the `vs_pspace` field from
+the 2.1.x kernel module as `vs_noalloc` field.
+
+For now, work-around that discrepancy by coupling the availability of
+the vs_noalloc field with the one of the vs_pspace one, as when both
+are returned from the module we can be sure that our struct layout
+matches again.
+
+Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
+---
+ cmd/zpool/zpool_main.c | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+diff --git a/cmd/zpool/zpool_main.c b/cmd/zpool/zpool_main.c
+index 5507f9d3f..98970abfe 100644
+--- a/cmd/zpool/zpool_main.c
++++ b/cmd/zpool/zpool_main.c
+@@ -2478,7 +2478,8 @@ print_status_config(zpool_handle_t *zhp, status_cbdata_t *cb, const char *name,
+ 
+       if (vs->vs_scan_removing != 0) {
+               (void) printf(gettext("  (removing)"));
+-      } else if (VDEV_STAT_VALID(vs_noalloc, vsc) && vs->vs_noalloc != 0) {
++      } else if (VDEV_STAT_VALID(vs_pspace, vsc)
++                     && VDEV_STAT_VALID(vs_noalloc, vsc) && vs->vs_noalloc != 0) {
+               (void) printf(gettext("  (non-allocating)"));
+       }
+ 

diff --git a/debian/patches/series b/debian/patches/series
index eba3f86e9a84f0e4595b0da4e13cc923bf9def94..5927d52110eab9586f7642d0c30b9b786d955c11 100644 (file)
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -11,3 +11,4 @@
 0011-Revert-zvol-Temporally-disable-blk-mq.patch
 0012-Fix-nfs_truncate_shares-without-etc-exports.d.patch
 0013-Workaround-UBSAN-errors-for-variable-arrays.patch
+0014-zpool-status-tighten-bounds-for-noalloc-stat-availab.patch