Zorro Lang <zlang@xxxxxxxxxx> writes: > On Fri, Jun 10, 2022 at 05:25:45PM +1000, Dave Chinner wrote: >> On Fri, Jun 10, 2022 at 01:35:36PM +0800, Xiubo Li wrote: >> > >> > On 6/9/22 6:53 PM, Luís Henriques wrote: >> > > CephFS doesn't have a maximum xattr size. Instead, it imposes a maximum >> > > size for the full set of xattrs names+values, which by default is 64K. >> > > And since ceph reports 4M as the blocksize (the default ceph object size), >> > > generic/486 will fail in this filesystem because it will end up using >> > > XATTR_SIZE_MAX to set the size of the 2nd (big) xattr value. >> > > >> > > The fix is to adjust the max size in attr_replace_test so that it takes >> > > into account the initial xattr name and value lengths. >> > > >> > > Signed-off-by: Luís Henriques <lhenriques@xxxxxxx> >> > > --- >> > > src/attr_replace_test.c | 7 ++++++- >> > > 1 file changed, 6 insertions(+), 1 deletion(-) >> > > >> > > diff --git a/src/attr_replace_test.c b/src/attr_replace_test.c >> > > index cca8dcf8ff60..1c8d1049a1d8 100644 >> > > --- a/src/attr_replace_test.c >> > > +++ b/src/attr_replace_test.c >> > > @@ -29,6 +29,11 @@ int main(int argc, char *argv[]) >> > > char *value; >> > > struct stat sbuf; >> > > size_t size = sizeof(value); >> > > + /* >> > > + * Take into account the initial (small) xattr name and value sizes and >> > > + * subtract them from the XATTR_SIZE_MAX maximum. >> > > + */ >> > > + size_t maxsize = XATTR_SIZE_MAX - strlen(name) - 1; >> > >> > Why not use the statfs to get the filesystem type first ? And then just >> > minus the strlen(name) for ceph only ? >> >> No. The test mechanism has no business knowing what filesystem type >> it is running on - the test itself is supposed to get the limits for >> the filesystem type from the test infrastructure. >> >> As I've already said: the right thing to do is to pass the maximum >> attr size for the test to use via the command line from the fstest >> itself. As per g/020, the fstests infrastructure is where we encode >> weird fs limit differences and behaviours based on $FSTYP. Hacking >> around weird filesystem specific behaviours deep inside random bits >> of test source code is not maintainable. >> >> AFAIA, only ceph is having a problem with this test, so it's trivial >> to encode into g/486 with: >> >> # ceph has a weird dynamic maximum xattr size and block size that is >> # much, much larger than the maximum supported attr size. Hence the >> # replace test can't auto-probe a sane attr size and so we have >> # to provide it with a maximum size that will work. >> max_attr_size=65536 >> [ "$FSTYP" = "ceph" ] && max_attr_size=64000 >> attr_replace_test -m $max_attr_size ..... >> ..... > > Agree. I'd recommend changing the attr_replace_test.c, make it have a > default max xattr size (keep using the XATTR_SIZE_MAX or define one if > it's not defined), then give it an optinal option which can specify a > customed max xattr size from outside. > > Then the test case (e.g. g/486) which uses attr_replace_test can > specify a max xattr size if it needs. And it's easier to figure > out what attr size is better for a specified fs in test case. Awesome, thanks. I'll send out next rev with these changes. Thank you all. Cheers, -- Luís
