On Tue, 2020-10-13 at 18:31 +0800, xiubli@xxxxxxxxxx wrote: > From: Xiubo Li <xiubli@xxxxxxxxxx> > > This will disable different mount points to share superblocks. > Why? What problem does this solve? Don't make us dig through random tracker bugs to determine this, please. :) Also, the subject mentions a "noshare" mount option, but the code below will be expecting sharesb/nosharesb. > URL: https://tracker.ceph.com/issues/46883 > Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx> > --- > fs/ceph/super.c | 12 ++++++++++++ > fs/ceph/super.h | 1 + > 2 files changed, 13 insertions(+) > > diff --git a/fs/ceph/super.c b/fs/ceph/super.c > index 2f530a111b3a..6f283e4d62ee 100644 > --- a/fs/ceph/super.c > +++ b/fs/ceph/super.c > @@ -159,6 +159,7 @@ enum { > Opt_quotadf, > Opt_copyfrom, > Opt_wsync, > + Opt_sharesb, > }; > > enum ceph_recover_session_mode { > @@ -199,6 +200,7 @@ static const struct fs_parameter_spec ceph_mount_parameters[] = { > fsparam_string ("source", Opt_source), > fsparam_u32 ("wsize", Opt_wsize), > fsparam_flag_no ("wsync", Opt_wsync), > + fsparam_flag_no ("sharesb", Opt_sharesb), > {} > }; > > @@ -455,6 +457,12 @@ static int ceph_parse_mount_param(struct fs_context *fc, > else > fsopt->flags |= CEPH_MOUNT_OPT_ASYNC_DIROPS; > break; > + case Opt_sharesb: > + if (!result.negated) > + fsopt->flags &= ~CEPH_MOUNT_OPT_NO_SHARE_SB; > + else > + fsopt->flags |= CEPH_MOUNT_OPT_NO_SHARE_SB; > + break; > default: > BUG(); > } > @@ -1007,6 +1015,10 @@ static int ceph_compare_super(struct super_block *sb, struct fs_context *fc) > > dout("ceph_compare_super %p\n", sb); > > + if (fsopt->flags & CEPH_MOUNT_OPT_NO_SHARE_SB || > + other->mount_options->flags & CEPH_MOUNT_OPT_NO_SHARE_SB) > + return 0; > + > if (compare_mount_options(fsopt, opt, other)) { > dout("monitor(s)/mount options don't match\n"); > return 0; > diff --git a/fs/ceph/super.h b/fs/ceph/super.h > index f097237a5ad3..e877c21196e5 100644 > --- a/fs/ceph/super.h > +++ b/fs/ceph/super.h > @@ -44,6 +44,7 @@ > #define CEPH_MOUNT_OPT_NOQUOTADF (1<<13) /* no root dir quota in statfs */ > #define CEPH_MOUNT_OPT_NOCOPYFROM (1<<14) /* don't use RADOS 'copy-from' op */ > #define CEPH_MOUNT_OPT_ASYNC_DIROPS (1<<15) /* allow async directory ops */ > +#define CEPH_MOUNT_OPT_NO_SHARE_SB (1<<16) /* disable sharing the same superblock */ > > #define CEPH_MOUNT_OPT_DEFAULT \ > (CEPH_MOUNT_OPT_DCACHE | \ -- Jeff Layton <jlayton@xxxxxxxxxx>
