| Message ID | 20210616144324.31652-5-julien@xen.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | tools/xenstored: Bug fixes + Improve Live-Update | expand |
> On 16 Jun 2021, at 15:43, Julien Grall <julien@xen.org> wrote: > > From: Julien Grall <jgrall@amazon.com> > > Currently, only liveupdate request can be delayed. The request can only > be performed by a privileged connection (e.g. dom0). So it is fine to > have no limits. > > In a follow-up patch we will want to delay request for unprivileged > connection as well. So it is best to apply a limit. > > For now and for simplicity, only a single request can be delayed > for a given unprivileged connection. > > Take the opportunity to tweak the prototype and provide a way to > bypass the quota check. This would be useful when the function > is called from the restore code. > > Signed-off-by: Julien Grall <jgrall@amazon.com> Reviewed-by: Luca Fancellu <luca.fancellu@arm.com> > --- > tools/xenstore/xenstored_control.c | 2 +- > tools/xenstore/xenstored_core.c | 11 ++++++++++- > tools/xenstore/xenstored_core.h | 3 ++- > 3 files changed, 13 insertions(+), 3 deletions(-) > > diff --git a/tools/xenstore/xenstored_control.c b/tools/xenstore/xenstored_control.c > index 7acc2d134f9f..1c24d4869eab 100644 > --- a/tools/xenstore/xenstored_control.c > +++ b/tools/xenstore/xenstored_control.c > @@ -737,7 +737,7 @@ static const char *lu_start(const void *ctx, struct connection *conn, > lu_status->timeout = to; > lu_status->started_at = time(NULL); > > - errno = delay_request(conn, conn->in, do_lu_start, NULL); > + errno = delay_request(conn, conn->in, do_lu_start, NULL, false); > > return NULL; > } > diff --git a/tools/xenstore/xenstored_core.c b/tools/xenstore/xenstored_core.c > index 41b26d7094c8..51d210828922 100644 > --- a/tools/xenstore/xenstored_core.c > +++ b/tools/xenstore/xenstored_core.c > @@ -279,10 +279,19 @@ static void call_delayed(struct connection *conn, struct delayed_request *req) > } > > int delay_request(struct connection *conn, struct buffered_data *in, > - bool (*func)(struct delayed_request *), void *data) > + bool (*func)(struct delayed_request *), void *data, > + bool no_quota_check) > { > struct delayed_request *req; > > + /* > + * Only allow one request can be delayed for an unprivileged > + * connection. > + */ > + if (!no_quota_check && domain_is_unprivileged(conn) && > + !list_empty(&conn->delayed)) > + return ENOSPC; > + > req = talloc(in, struct delayed_request); > if (!req) > return ENOMEM; > diff --git a/tools/xenstore/xenstored_core.h b/tools/xenstore/xenstored_core.h > index 89ce155e755b..34839b34f6e9 100644 > --- a/tools/xenstore/xenstored_core.h > +++ b/tools/xenstore/xenstored_core.h > @@ -213,7 +213,8 @@ char *get_parent(const void *ctx, const char *node); > > /* Delay a request. */ > int delay_request(struct connection *conn, struct buffered_data *in, > - bool (*func)(struct delayed_request *), void *data); > + bool (*func)(struct delayed_request *), void *data, > + bool no_quota_check); > > /* Tracing infrastructure. */ > void trace_create(const void *data, const char *type); > -- > 2.17.1 > >
On 16.06.21 16:43, Julien Grall wrote: > From: Julien Grall <jgrall@amazon.com> > > Currently, only liveupdate request can be delayed. The request can only > be performed by a privileged connection (e.g. dom0). So it is fine to > have no limits. > > In a follow-up patch we will want to delay request for unprivileged > connection as well. So it is best to apply a limit. > > For now and for simplicity, only a single request can be delayed > for a given unprivileged connection. > > Take the opportunity to tweak the prototype and provide a way to > bypass the quota check. This would be useful when the function > is called from the restore code. > > Signed-off-by: Julien Grall <jgrall@amazon.com> Reviewed-by: Juergen Gross <jgross@suse.com> Juergen
diff --git a/tools/xenstore/xenstored_control.c b/tools/xenstore/xenstored_control.c index 7acc2d134f9f..1c24d4869eab 100644 --- a/tools/xenstore/xenstored_control.c +++ b/tools/xenstore/xenstored_control.c @@ -737,7 +737,7 @@ static const char *lu_start(const void *ctx, struct connection *conn, lu_status->timeout = to; lu_status->started_at = time(NULL); - errno = delay_request(conn, conn->in, do_lu_start, NULL); + errno = delay_request(conn, conn->in, do_lu_start, NULL, false); return NULL; } diff --git a/tools/xenstore/xenstored_core.c b/tools/xenstore/xenstored_core.c index 41b26d7094c8..51d210828922 100644 --- a/tools/xenstore/xenstored_core.c +++ b/tools/xenstore/xenstored_core.c @@ -279,10 +279,19 @@ static void call_delayed(struct connection *conn, struct delayed_request *req) } int delay_request(struct connection *conn, struct buffered_data *in, - bool (*func)(struct delayed_request *), void *data) + bool (*func)(struct delayed_request *), void *data, + bool no_quota_check) { struct delayed_request *req; + /* + * Only allow one request can be delayed for an unprivileged + * connection. + */ + if (!no_quota_check && domain_is_unprivileged(conn) && + !list_empty(&conn->delayed)) + return ENOSPC; + req = talloc(in, struct delayed_request); if (!req) return ENOMEM; diff --git a/tools/xenstore/xenstored_core.h b/tools/xenstore/xenstored_core.h index 89ce155e755b..34839b34f6e9 100644 --- a/tools/xenstore/xenstored_core.h +++ b/tools/xenstore/xenstored_core.h @@ -213,7 +213,8 @@ char *get_parent(const void *ctx, const char *node); /* Delay a request. */ int delay_request(struct connection *conn, struct buffered_data *in, - bool (*func)(struct delayed_request *), void *data); + bool (*func)(struct delayed_request *), void *data, + bool no_quota_check); /* Tracing infrastructure. */ void trace_create(const void *data, const char *type);