在 2022/4/20 16:50, chenxiaosong (A) 写道:
在 2022/4/12 22:27, Trond Myklebust 写道:
It will clear ENOSPC, EDQUOT and EFBIG. It should not clear other
errors that are not supposed to be reported by write().
As I keep repeating, that is _documented behaviour_!
Hi Trond:
You may mean that write(2) manpage described:
Since Linux 4.13, errors from write-back come with a promise that
they may be reported by subsequent. write(2) requests, and will be
reported by a subsequent fsync(2) (whether or not they were also
reported by write(2)).
The manpage mentioned that "reported by a subsequent fsync(2)", your
patch[1] clear the wb err on _async_ write(), and wb err will _not_ be
reported by subsequent fsync(2), is it documented behaviour?
All other filesystems will _not_ clear any wb err on _async_ write().
[1]
https://patchwork.kernel.org/project/linux-nfs/patch/20220411213346.762302-4-trondmy@xxxxxxxxxx/
Hi Trond:
write(2) manpage described:
On some filesystems, including NFS, it does not even guarantee that
space has successfully been reserved for the data. In this case, some
errors might be delayed until a future write(2), fsync(2), or even
close(2). The only way to be sure is to call fsync(2) after you are
done writing all your data.
Maybe it mean that: writeback errors of NFS is delayed until future sync
write() and fsync(), because sync write() will call fsync(). We all
agreed that close()->flush() should not clear writeback errors, should
async write() do the same thing like other filesystems?
