Commit 8e02b06882 for qemu.org

commit 8e02b06882e5742fb760138e3db627a8591bdef3
Author: Niklas Cassel <cassel@kernel.org>
Date:   Tue Aug 11 15:32:36 2026 +0200

    file-posix: fix zone write granularity assignment for zoned block devices

    In the ZBC and ZAC specifications, the requirement is that the write
    granularity matches the physical block size.

    However, in the ZNS specification, the requirement is simply that the
    write granularity matches the logical block size.

    See:
    https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a805a4fa4fa376bbc145762bb8b09caa2fa8af48

    In Linux, there is a zone_write_granularity sysfs property which abstracts
    this away, so let's make use of it.

    Currently, it is theoretically possible that QEMU presents an inflated
    write granularity for NVMe devices where the physical block size is larger
    than the logical block size.

    Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
    Fixes: a3c41f06d5a8 ("file-posix: add tracking of the zone write pointers")
    Signed-off-by: Niklas Cassel <cassel@kernel.org>
    Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
    Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

diff --git a/block/file-posix.c b/block/file-posix.c
index 01037f4b5c..9aad156aad 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -1493,7 +1493,7 @@ static void raw_refresh_zoned_limits(BlockDriverState *bs, struct stat *st,
         bs->bl.max_append_sectors = ret >> BDRV_SECTOR_BITS;
     }

-    ret = get_sysfs_long_val(st, "physical_block_size");
+    ret = get_sysfs_long_val(st, "zone_write_granularity");
     if (ret >= 0) {
         bs->bl.write_granularity = ret;
     }