On 06/29/2015 04:33 PM, Atsushi Kumagai wrote: > Hello Zhou, > >> Currently, there is no obvious description in IMPLEMENTATION for >> distinguishing the lost pages resulted by ENOSPACE errors or others. >> So, it is added. >> >> Signed-off-by: Zhou Wenjian<zhouwj-fnst at cn.fujitsu.com> >> --- >> IMPLEMENTATION | 2 ++ >> 1 files changed, 2 insertions(+), 0 deletions(-) >> >> diff --git a/IMPLEMENTATION b/IMPLEMENTATION >> index 72df5d5..70a3f7c 100644 >> --- a/IMPLEMENTATION >> +++ b/IMPLEMENTATION >> @@ -240,6 +240,8 @@ >> The page header and page data are written in pairs. When writing page data >> (pfn N+1), if ENOSPACE error happens, the page headers after N won't be >> written either. >> + When reading page from incomplete core, only the page lost by ENOSPACE errors >> + has 0 in its corresponding page descriptor's member offset. > > I'm not sure this is correct. > Could you point me where is the code which sets 0 to the page_desc->offset > of the lost page ? > There is no code to set it. Since the data lost is filled with zero when it is read, the page_desc->offset will also be zero. And zero page has its own offset not equal 0. So we can distinguish them with their member offset. -- Thanks Zhou Wenjian
