在 2012-12-18二的 13:41 +0100，Vasilis Liaskovitis写道：
This patch adds a 'SIZE' type property to qdev.
It will make dimm description more convenient by allowing sizes to be specified with K,M,G,T prefixes instead of number of bytes e.g.: -device dimm,id=mem0,size=2G,bus=membus.0
Credits go to Ian Molton for original patch. See: http://patchwork.ozlabs.org/patch/38835/
Signed-off-by: Vasilis Liaskovitis vasilis.liaskovitis@profitbricks.com
hw/qdev-properties.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++++ hw/qdev-properties.h | 3 ++ qemu-option.c | 2 +- qemu-option.h | 2 + 4 files changed, 66 insertions(+), 1 deletions(-)
diff --git a/hw/qdev-properties.c b/hw/qdev-properties.c index 81d901c..a77f760 100644 --- a/hw/qdev-properties.c +++ b/hw/qdev-properties.c @@ -1279,3 +1279,63 @@ void qemu_add_globals(void) { qemu_opts_foreach(qemu_find_opts("global"), qdev_add_one_global, NULL, 0); }
+/* --- 64bit unsigned int 'size' type --- */
+static void get_size(Object *obj, Visitor *v, void *opaque,
const char *name, Error **errp)+{
- DeviceState *dev = DEVICE(obj);
- Property *prop = opaque;
- uint64_t *ptr = qdev_get_prop_ptr(dev, prop);
- visit_type_size(v, ptr, name, errp);
+}
+static void set_size(Object *obj, Visitor *v, void *opaque,
const char *name, Error **errp)+{
- DeviceState *dev = DEVICE(obj);
- Property *prop = opaque;
- uint64_t *ptr = qdev_get_prop_ptr(dev, prop);
- if (dev->state != DEV_STATE_CREATED) {
error_set(errp, QERR_PERMISSION_DENIED);return;- }
- visit_type_size(v, ptr, name, errp);
+}
+static int parse_size(DeviceState *dev, Property *prop, const char *str) +{
- uint64_t *ptr = qdev_get_prop_ptr(dev, prop);
- Error *errp = NULL;
- if (str != NULL) {
parse_option_size(prop->name, str, ptr, &errp);- }
- assert_no_error(errp);
- return 0;
+}
+static int print_size(DeviceState *dev, Property *prop, char *dest, size_t len) +{
- uint64_t *ptr = qdev_get_prop_ptr(dev, prop);
- char suffixes[] = {'T', 'G', 'M', 'K', 'B'};
- int i = 0;
- uint64_t div;
- for (div = (long int)1 << 40; !(*ptr / div) ; div >>= 10) {
i++;- }
- return snprintf(dest, len, "%0.03f%c", (double)*ptr/div, suffixes[i]);
^^^^^^ ^^^^^^^^^^^^^^^
+}
IMHO, you may need (double)(*ptr/div), for type cast is right associated.
+PropertyInfo qdev_prop_size = {
- .name = "size",
- .parse = parse_size,
- .print = print_size,
- .get = get_size,
- .set = set_size,
+}; diff --git a/hw/qdev-properties.h b/hw/qdev-properties.h index 5b046ab..0182bef 100644 --- a/hw/qdev-properties.h +++ b/hw/qdev-properties.h @@ -14,6 +14,7 @@ extern PropertyInfo qdev_prop_uint64; extern PropertyInfo qdev_prop_hex8; extern PropertyInfo qdev_prop_hex32; extern PropertyInfo qdev_prop_hex64; +extern PropertyInfo qdev_prop_size; extern PropertyInfo qdev_prop_string; extern PropertyInfo qdev_prop_chr; extern PropertyInfo qdev_prop_ptr; @@ -67,6 +68,8 @@ extern PropertyInfo qdev_prop_pci_host_devaddr; DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_hex32, uint32_t) #define DEFINE_PROP_HEX64(_n, _s, _f, _d) \ DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_hex64, uint64_t) +#define DEFINE_PROP_SIZE(_n, _s, _f, _d) \
- DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_size, uint64_t)
#define DEFINE_PROP_PCI_DEVFN(_n, _s, _f, _d) \ DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_pci_devfn, int32_t)
diff --git a/qemu-option.c b/qemu-option.c index 27891e7..38e0a11 100644 --- a/qemu-option.c +++ b/qemu-option.c @@ -203,7 +203,7 @@ static void parse_option_number(const char *name, const char *value, } }
-static void parse_option_size(const char *name, const char *value, +void parse_option_size(const char *name, const char *value, uint64_t *ret, Error **errp) { char *postfix; diff --git a/qemu-option.h b/qemu-option.h index ca72986..b8ee5b3 100644 --- a/qemu-option.h +++ b/qemu-option.h @@ -152,5 +152,7 @@ typedef int (*qemu_opts_loopfunc)(QemuOpts *opts, void *opaque); int qemu_opts_print(QemuOpts *opts, void *dummy); int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func, void *opaque, int abort_on_failure); +void parse_option_size(const char *name, const char *value,
uint64_t *ret, Error **errp);#endif
On 03/20/2013 12:06 AM, li guang wrote:
- return snprintf(dest, len, "%0.03f%c", (double)*ptr/div, suffixes[i]);
^^^^^^ ^^^^^^^^^^^^^^^+}
IMHO, you may need (double)(*ptr/div), for type cast is right associated.
No, the code as written is correct, and your proposal would be wrong. As written, it is evaluated as:
((double)*ptr) / div
which promotes the division to floating point. Your proposal would do the division (*ptr/div) as an integral (truncating) division, and only then cast the result to double.
在 2013-03-20三的 08:24 -0600，Eric Blake写道：
On 03/20/2013 12:06 AM, li guang wrote:
- return snprintf(dest, len, "%0.03f%c", (double)*ptr/div, suffixes[i]);
^^^^^^ ^^^^^^^^^^^^^^^+}
IMHO, you may need (double)(*ptr/div), for type cast is right associated.
No, the code as written is correct, and your proposal would be wrong. As written, it is evaluated as:
((double)*ptr) / div
which promotes the division to floating point. Your proposal would do the division (*ptr/div) as an integral (truncating) division, and only then cast the result to double.
Yes, you're right, amazing c type cast!
-
Eric Blake -
li guang