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| author | Elliott Mitchell <ehem+freebsd@m5p.com> | 2021-06-06 00:43:13 +0000 |
|---|---|---|
| committer | Roger Pau Monné <royger@FreeBSD.org> | 2023-03-29 07:51:41 +0000 |
| commit | 1797ff962769aac6822cde45719ed02c18d6cdb8 (patch) | |
| tree | 38609a11cae9ca82737f7febaff17ff6c05c391b | |
| parent | 2b2415bafa0dda36244f0fedef9f8750b2868dea (diff) | |
| download | src-1797ff962769aac6822cde45719ed02c18d6cdb8.tar.gz src-1797ff962769aac6822cde45719ed02c18d6cdb8.zip | |
xen/intr: cleanup event channel number use
Consistently use ~0 instead of 0 when clearing xenisrc structures.
0 is a valid event channel number, even though it is reserved by Xen.
Whereas ~0 is guaranteed invalid.
Reviewed by: royger
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30743
| -rw-r--r-- | sys/x86/xen/xen_intr.c | 24 |
1 files changed, 18 insertions, 6 deletions
diff --git a/sys/x86/xen/xen_intr.c b/sys/x86/xen/xen_intr.c index 4e16778874b5..3a053b10f915 100644 --- a/sys/x86/xen/xen_intr.c +++ b/sys/x86/xen/xen_intr.c @@ -117,9 +117,8 @@ DPCPU_DEFINE_STATIC(struct xen_intr_pcpu_data, xen_intr_pcpu) = { DPCPU_DECLARE(struct vcpu_info *, vcpu_info); -#define XEN_INVALID_EVTCHN 0 /* Invalid event channel */ - -#define is_valid_evtchn(x) ((x) != XEN_INVALID_EVTCHN) +#define INVALID_EVTCHN (~(evtchn_port_t)0) /* Invalid event channel */ +#define is_valid_evtchn(x) ((uintmax_t)(x) < NR_EVENT_CHANNELS) struct xenisrc { struct intsrc xi_intsrc; @@ -372,7 +371,7 @@ xen_intr_release_isrc(struct xenisrc *isrc) } isrc->xi_cpu = 0; isrc->xi_type = EVTCHN_TYPE_UNBOUND; - isrc->xi_port = 0; + isrc->xi_port = INVALID_EVTCHN; isrc->xi_cookie = NULL; mtx_unlock(&xen_intr_isrc_lock); return (0); @@ -613,6 +612,19 @@ xen_intr_init(void *dummy __unused) if (!xen_domain()) return (0); + _Static_assert(is_valid_evtchn(0), + "is_valid_evtchn(0) fails (unused by Xen, but valid by interface"); + _Static_assert(is_valid_evtchn(NR_EVENT_CHANNELS - 1), + "is_valid_evtchn(max) fails (is a valid channel)"); + _Static_assert(!is_valid_evtchn(NR_EVENT_CHANNELS), + "is_valid_evtchn(>max) fails (NOT a valid channel)"); + _Static_assert(!is_valid_evtchn(~(evtchn_port_t)0), + "is_valid_evtchn(maxint) fails (overflow?)"); + _Static_assert(!is_valid_evtchn(INVALID_EVTCHN), + "is_valid_evtchn(INVALID_EVTCHN) fails (must be invalid!)"); + _Static_assert(!is_valid_evtchn(-1), + "is_valid_evtchn(-1) fails (negative are invalid)"); + mtx_init(&xen_intr_isrc_lock, "xen-irq-lock", NULL, MTX_DEF); /* @@ -769,7 +781,7 @@ xen_intr_resume(struct pic *unused, bool suspend_cancelled) vector = first_evtchn_irq + isrc_idx; isrc = (struct xenisrc *)intr_lookup_source(vector); if (isrc != NULL) { - isrc->xi_port = 0; + isrc->xi_port = INVALID_EVTCHN; switch (isrc->xi_type) { case EVTCHN_TYPE_IPI: xen_rebind_ipi(isrc); @@ -1292,7 +1304,7 @@ int xen_intr_get_evtchn_from_port(evtchn_port_t port, xen_intr_handle_t *handlep) { - if (!is_valid_evtchn(port) || port >= NR_EVENT_CHANNELS) + if (!is_valid_evtchn(port)) return (EINVAL); if (handlep == NULL) { |