On Thu, Jul 11, 2013 at 10:56:17PM +0200, Koen De Wit wrote: > Commit 8d082fb727ac11930ea20bf1612e334ea7c2b697 (Btrfs: do not mount when > we have a sectorsize unequal to PAGE_SIZE) requires the sectorsize to be > equal to the pagesize for the filesystem to be mountable. > > The nodesize and leafsize should be equal, and not larger than 65536. > > Adding this information to the manpage and usage instructions of mkfs.btrfs.
Please don't forget to add your signed-off-by line. > --- a/man/mkfs.btrfs.8.in > +++ b/man/mkfs.btrfs.8.in > @@ -46,7 +46,8 @@ there is a filesystem or partition table on the device > already. > .TP > \fB\-l\fR, \fB\-\-leafsize \fIsize\fR > Specify the leaf size, the least data item in which btrfs stores data. The > -default value is the page size. > +default value is the page size. Must be a multiple of the sectorsize, but > +not larger than 65536. Should be equal to the nodesize. As implemented now, setting one of leafsize/nodesize will set both, so it's not necessary to specify both. The help text should reflect that. > -Specify the nodesize. By default the value is set to the pagesize. > +Specify the nodesize. By default the value is set to the pagesize. Must be a > +multiple of the sectorsize, but not larger than 65536. Should be equal to the > +leafsize. > .TP > \fB\-s\fR, \fB\-\-sectorsize \fIsize\fR > -Specify the sectorsize, the minimum block allocation. > +Specify the sectorsize, the minimum block allocation. The default value is > +the pagesize. If the sectorsize differs from the pagesize, the created > +filesystem cannot be mounted by the current kernel. Therefore it is not > +recommended to use this option. "... unless you know what you're doing." :) > --- a/mkfs.c > +++ b/mkfs.c > @@ -319,7 +319,7 @@ static void print_usage(void) > fprintf(stderr, "\t -m --metadata metadata profile, values like data > profile\n"); > fprintf(stderr, "\t -M --mixed mix metadata and data together\n"); > fprintf(stderr, "\t -n --nodesize size of btree nodes\n"); > - fprintf(stderr, "\t -s --sectorsize min block allocation\n"); > + fprintf(stderr, "\t -s --sectorsize min block allocation (not mountable > by current kernel)\n"); What if I'm on a ppc64 box? This message will be confusing. I'd stick 'may' into (...) I'll fix the text wording when committing the patch, no need to resend. david -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
