[libvirt] [PATCH] storage: Round up capacity for LVM volume creation
If vol->capacity is odd, the capacity will be rounded down by devision, this patch is to round it up instead of rounding down, to be safer in case of one writes to the volume with the size he used to create. * src/storage/storage_backend_logical.c --- src/storage/storage_backend_logical.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-) diff --git a/src/storage/storage_backend_logical.c b/src/storage/storage_backend_logical.c index 203fe5d..2057692 100644 --- a/src/storage/storage_backend_logical.c +++ b/src/storage/storage_backend_logical.c @@ -604,7 +604,10 @@ virStorageBackendLogicalCreateVol(virConnectPtr conn, cmdargv = cmdargvsnap; } - snprintf(size, sizeof(size)-1, "%lluK", vol->capacity/1024); + unsigned long long int capacity; + capacity = vol->capacity/1024 + (vol->capacity%1024 > 0 ? 1 : 0); + + snprintf(size, sizeof(size)-1, "%lluK", capacity); size[sizeof(size)-1] = '\0'; vol->type = VIR_STORAGE_VOL_BLOCK; -- 1.7.3.2
On Sat, Jan 22, 2011 at 07:18:00PM +0800, Osier Yang wrote:
If vol->capacity is odd, the capacity will be rounded down by devision, this patch is to round it up instead of rounding down, to be safer in case of one writes to the volume with the size he used to create.
* src/storage/storage_backend_logical.c --- src/storage/storage_backend_logical.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-)
diff --git a/src/storage/storage_backend_logical.c b/src/storage/storage_backend_logical.c index 203fe5d..2057692 100644 --- a/src/storage/storage_backend_logical.c +++ b/src/storage/storage_backend_logical.c @@ -604,7 +604,10 @@ virStorageBackendLogicalCreateVol(virConnectPtr conn, cmdargv = cmdargvsnap; }
- snprintf(size, sizeof(size)-1, "%lluK", vol->capacity/1024); + unsigned long long int capacity; + capacity = vol->capacity/1024 + (vol->capacity%1024 > 0 ? 1 : 0); + + snprintf(size, sizeof(size)-1, "%lluK", capacity); size[sizeof(size)-1] = '\0';
vol->type = VIR_STORAGE_VOL_BLOCK;
To fix such rounding issues I would usually do capacity = (vol->capacity + 1023) /1024; instead, it's really easier to read :-) But the principle of the patch looks right to me ! Daniel -- Daniel Veillard | libxml Gnome XML XSLT toolkit http://xmlsoft.org/ daniel@veillard.com | Rpmfind RPM search engine http://rpmfind.net/ http://veillard.com/ | virtualization library http://libvirt.org/
于 2011年01月24日 11:02, Daniel Veillard 写道:
On Sat, Jan 22, 2011 at 07:18:00PM +0800, Osier Yang wrote:
If vol->capacity is odd, the capacity will be rounded down by devision, this patch is to round it up instead of rounding down, to be safer in case of one writes to the volume with the size he used to create.
* src/storage/storage_backend_logical.c --- src/storage/storage_backend_logical.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-)
diff --git a/src/storage/storage_backend_logical.c b/src/storage/storage_backend_logical.c index 203fe5d..2057692 100644 --- a/src/storage/storage_backend_logical.c +++ b/src/storage/storage_backend_logical.c @@ -604,7 +604,10 @@ virStorageBackendLogicalCreateVol(virConnectPtr conn, cmdargv = cmdargvsnap; }
- snprintf(size, sizeof(size)-1, "%lluK", vol->capacity/1024); + unsigned long long int capacity; + capacity = vol->capacity/1024 + (vol->capacity%1024> 0 ? 1 : 0); + + snprintf(size, sizeof(size)-1, "%lluK", capacity); size[sizeof(size)-1] = '\0';
vol->type = VIR_STORAGE_VOL_BLOCK;
To fix such rounding issues I would usually do capacity = (vol->capacity + 1023) /1024;
instead, it's really easier to read :-)
Yeah, it looks much better, will update, thanks. :-)
But the principle of the patch looks right to me !
Daniel
participants (2)
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Daniel Veillard -
Osier Yang