[PATCH v2] block: make BlockConf.*_size properties 32-bit

[PATCH v2] block: make BlockConf.*_size properties 32-bit

[Roman Kagan]

Devices (virtio-blk, scsi, etc.) and the block layer are happy to use
32-bit for logical_block_size, physical_block_size, and min_io_size.
However, the properties in BlockConf are defined as uint16_t limiting
the values to 32768.

This appears unnecessary tight, and we've seen bigger block sizes handy
at times.

Make them 32 bit instead and lift the limitation up to 2 MiB which
appears to be good enough for everybody.

As the values can now be fairly big and awkward to type, make the
property setter accept common size suffixes (k, m).

Signed-off-by: Roman Kagan <rvkagan@yandex-team.ru>
---
v1 -> v2:
- cap the property at 2 MiB [Eric]
- accept size suffixes

 include/hw/block/block.h     |  8 ++++----
 include/hw/qdev-properties.h |  2 +-
 hw/core/qdev-properties.c    | 31 +++++++++++++++++++++----------
 3 files changed, 26 insertions(+), 15 deletions(-)

diff --git a/include/hw/block/block.h b/include/hw/block/block.h
index d7246f3862..9dd6bba56a 100644
--- a/include/hw/block/block.h
+++ b/include/hw/block/block.h
@@ -18,9 +18,9 @@
 
 typedef struct BlockConf {
     BlockBackend *blk;
-    uint16_t physical_block_size;
-    uint16_t logical_block_size;
-    uint16_t min_io_size;
+    uint32_t physical_block_size;
+    uint32_t logical_block_size;
+    uint32_t min_io_size;
     uint32_t opt_io_size;
     int32_t bootindex;
     uint32_t discard_granularity;
@@ -51,7 +51,7 @@ static inline unsigned int get_physical_block_exp(BlockConf *conf)
                           _conf.logical_block_size),                    \
     DEFINE_PROP_BLOCKSIZE("physical_block_size", _state,                \
                           _conf.physical_block_size),                   \
-    DEFINE_PROP_UINT16("min_io_size", _state, _conf.min_io_size, 0),    \
+    DEFINE_PROP_UINT32("min_io_size", _state, _conf.min_io_size, 0),    \
     DEFINE_PROP_UINT32("opt_io_size", _state, _conf.opt_io_size, 0),    \
     DEFINE_PROP_UINT32("discard_granularity", _state,                   \
                        _conf.discard_granularity, -1),                  \
diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
index f161604fb6..f9e0f8c041 100644
--- a/include/hw/qdev-properties.h
+++ b/include/hw/qdev-properties.h
@@ -197,7 +197,7 @@ extern const PropertyInfo qdev_prop_pcie_link_width;
 #define DEFINE_PROP_BIOS_CHS_TRANS(_n, _s, _f, _d) \
     DEFINE_PROP_SIGNED(_n, _s, _f, _d, qdev_prop_bios_chs_trans, int)
 #define DEFINE_PROP_BLOCKSIZE(_n, _s, _f) \
-    DEFINE_PROP_UNSIGNED(_n, _s, _f, 0, qdev_prop_blocksize, uint16_t)
+    DEFINE_PROP_UNSIGNED(_n, _s, _f, 0, qdev_prop_blocksize, uint32_t)
 #define DEFINE_PROP_PCI_HOST_DEVADDR(_n, _s, _f) \
     DEFINE_PROP(_n, _s, _f, qdev_prop_pci_host_devaddr, PCIHostDeviceAddress)
 #define DEFINE_PROP_OFF_AUTO_PCIBAR(_n, _s, _f, _d) \
diff --git a/hw/core/qdev-properties.c b/hw/core/qdev-properties.c
index 2047114fca..a571be7607 100644
--- a/hw/core/qdev-properties.c
+++ b/hw/core/qdev-properties.c
@@ -14,6 +14,7 @@
 #include "qapi/visitor.h"
 #include "chardev/char.h"
 #include "qemu/uuid.h"
+#include "qemu/units.h"
 
 void qdev_prop_set_after_realize(DeviceState *dev, const char *name,
                                   Error **errp)
@@ -729,30 +730,39 @@ const PropertyInfo qdev_prop_pci_devfn = {
 
 /* --- blocksize --- */
 
+/* lower limit is sector size */
+#define MIN_BLOCK_SIZE          512
+#define MIN_BLOCK_SIZE_STR      "512 B"
+/* upper limit is arbitrary, 2 MiB looks sufficient */
+#define MAX_BLOCK_SIZE          (2 * MiB)
+#define MAX_BLOCK_SIZE_STR      "2 MiB"
+
 static void set_blocksize(Object *obj, Visitor *v, const char *name,
                           void *opaque, Error **errp)
 {
     DeviceState *dev = DEVICE(obj);
     Property *prop = opaque;
-    uint16_t value, *ptr = qdev_get_prop_ptr(dev, prop);
+    uint32_t *ptr = qdev_get_prop_ptr(dev, prop);
+    uint64_t value;
     Error *local_err = NULL;
-    const int64_t min = 512;
-    const int64_t max = 32768;
 
     if (dev->realized) {
         qdev_prop_set_after_realize(dev, name, errp);
         return;
     }
 
-    visit_type_uint16(v, name, &value, &local_err);
+    visit_type_size(v, name, &value, &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
         return;
     }
     /* value of 0 means "unset" */
-    if (value && (value < min || value > max)) {
-        error_setg(errp, QERR_PROPERTY_VALUE_OUT_OF_RANGE,
-                   dev->id ? : "", name, (int64_t)value, min, max);
+    if (value && (value < MIN_BLOCK_SIZE || value > MAX_BLOCK_SIZE)) {
+        error_setg(errp,
+                   "Property %s.%s doesn't take value %" PRIu64
+                   " (minimum: " MIN_BLOCK_SIZE_STR
+                   ", maximum: " MAX_BLOCK_SIZE_STR ")",
+                   dev->id ? : "", name, value);
         return;
     }
 
@@ -768,9 +778,10 @@ static void set_blocksize(Object *obj, Visitor *v, const char *name,
 }
 
 const PropertyInfo qdev_prop_blocksize = {
-    .name  = "uint16",
-    .description = "A power of two between 512 and 32768",
-    .get   = get_uint16,
+    .name  = "size",
+    .description = "A power of two between " MIN_BLOCK_SIZE_STR
+                   " and " MAX_BLOCK_SIZE_STR,
+    .get   = get_uint32,
     .set   = set_blocksize,
     .set_default_value = set_default_value_uint,
 };
-- 
2.25.1

Re: [PATCH v2] block: make BlockConf.*_size properties 32-bit

[Eric Blake]

On 3/26/20 1:52 AM, Roman Kagan wrote:
> Devices (virtio-blk, scsi, etc.) and the block layer are happy to use
> 32-bit for logical_block_size, physical_block_size, and min_io_size.
> However, the properties in BlockConf are defined as uint16_t limiting
> the values to 32768.
> 
> This appears unnecessary tight, and we've seen bigger block sizes handy
> at times.
> 
> Make them 32 bit instead and lift the limitation up to 2 MiB which
> appears to be good enough for everybody.

and matches the current qemu limit for qcow2 cluster sizes

> 
> As the values can now be fairly big and awkward to type, make the
> property setter accept common size suffixes (k, m).
> 
> Signed-off-by: Roman Kagan <rvkagan@yandex-team.ru>
> ---
> v1 -> v2:
> - cap the property at 2 MiB [Eric]
> - accept size suffixes
> 

> +++ b/hw/core/qdev-properties.c
> @@ -14,6 +14,7 @@
>   #include "qapi/visitor.h"
>   #include "chardev/char.h"
>   #include "qemu/uuid.h"
> +#include "qemu/units.h"
>   
>   void qdev_prop_set_after_realize(DeviceState *dev, const char *name,
>                                     Error **errp)
> @@ -729,30 +730,39 @@ const PropertyInfo qdev_prop_pci_devfn = {
>   
>   /* --- blocksize --- */
>   
> +/* lower limit is sector size */
> +#define MIN_BLOCK_SIZE          512
> +#define MIN_BLOCK_SIZE_STR      "512 B"
> +/* upper limit is arbitrary, 2 MiB looks sufficient */
> +#define MAX_BLOCK_SIZE          (2 * MiB)
> +#define MAX_BLOCK_SIZE_STR      "2 MiB"

For this comment, I might add that it matches our limit for qcow2 
cluster size.

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
Virtualization:  qemu.org | libvirt.org