[PATCH 1/8] m25p80: Improve error when the backend file size does not match the device

[Cédric Le Goater]

Currently, when a block backend is attached to a m25p80 device and the
associated file size does not match the flash model, QEMU complains
with the error message "failed to read the initial flash content".
This is confusing for the user.

Use blk_check_size_and_read_all() instead of blk_pread() to improve
the reported error.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Peter Delevoryas <peter@pjd.dev>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20221115151000.2080833-1-clg@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
---

  breakage with commit a4b15a8b9e ("pflash: Only read non-zero parts
  of backend image") when using -snaphot.

 hw/block/m25p80.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/hw/block/m25p80.c b/hw/block/m25p80.c
index 802d2eb021..dc5ffbc4ff 100644
--- a/hw/block/m25p80.c
+++ b/hw/block/m25p80.c
@@ -24,6 +24,7 @@
 #include "qemu/osdep.h"
 #include "qemu/units.h"
 #include "sysemu/block-backend.h"
+#include "hw/block/block.h"
 #include "hw/qdev-properties.h"
 #include "hw/qdev-properties-system.h"
 #include "hw/ssi/ssi.h"
@@ -1615,8 +1616,7 @@ static void m25p80_realize(SSIPeripheral *ss, Error 
**errp)
         trace_m25p80_binding(s);
         s->storage = blk_blockalign(s->blk, s->size);
 
-        if (blk_pread(s->blk, 0, s->size, s->storage, 0) < 0) {
-            error_setg(errp, "failed to read the initial flash content");
+        if (!blk_check_size_and_read_all(s->blk, s->storage, s->size, errp)) {
             return;
         }
     } else {
-- 
2.39.1