diff options
author | Anthony PERARD <anthony.perard@citrix.com> | 2019-06-18 12:23:41 +0100 |
---|---|---|
committer | Anthony PERARD <anthony.perard@citrix.com> | 2019-06-24 10:42:30 +0100 |
commit | 34fbbc164fded65341f9fc299b118c90925d5b1f (patch) | |
tree | 23b6c39bb6dc9174f0ccd49f95d405e6173433a3 /hw/i386 | |
parent | 345f42b4be9f9975ff3f7f3e95acae4f67c74f89 (diff) |
xen: Avoid VLA
Avoid using a variable length array.
We allocate the `dirty_bitmap' buffer only once when we start tracking
for dirty bits.
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190618112341.513-5-anthony.perard@citrix.com>
Diffstat (limited to 'hw/i386')
-rw-r--r-- | hw/i386/xen/xen-hvm.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/hw/i386/xen/xen-hvm.c b/hw/i386/xen/xen-hvm.c index 2939122e7c..ed9c37c72d 100644 --- a/hw/i386/xen/xen-hvm.c +++ b/hw/i386/xen/xen-hvm.c @@ -120,6 +120,8 @@ typedef struct XenIOState { DeviceListener device_listener; hwaddr free_phys_offset; const XenPhysmap *log_for_dirtybit; + /* Buffer used by xen_sync_dirty_bitmap */ + unsigned long *dirty_bitmap; Notifier exit; Notifier suspend; @@ -465,6 +467,8 @@ static int xen_remove_from_physmap(XenIOState *state, QLIST_REMOVE(physmap, list); if (state->log_for_dirtybit == physmap) { state->log_for_dirtybit = NULL; + g_free(state->dirty_bitmap); + state->dirty_bitmap = NULL; } g_free(physmap); @@ -615,7 +619,7 @@ static void xen_sync_dirty_bitmap(XenIOState *state, { hwaddr npages = size >> TARGET_PAGE_BITS; const int width = sizeof(unsigned long) * 8; - unsigned long bitmap[DIV_ROUND_UP(npages, width)]; + size_t bitmap_size = DIV_ROUND_UP(npages, width); int rc, i, j; const XenPhysmap *physmap = NULL; @@ -627,13 +631,14 @@ static void xen_sync_dirty_bitmap(XenIOState *state, if (state->log_for_dirtybit == NULL) { state->log_for_dirtybit = physmap; + state->dirty_bitmap = g_new(unsigned long, bitmap_size); } else if (state->log_for_dirtybit != physmap) { /* Only one range for dirty bitmap can be tracked. */ return; } rc = xen_track_dirty_vram(xen_domid, start_addr >> TARGET_PAGE_BITS, - npages, bitmap); + npages, state->dirty_bitmap); if (rc < 0) { #ifndef ENODATA #define ENODATA ENOENT @@ -647,8 +652,8 @@ static void xen_sync_dirty_bitmap(XenIOState *state, return; } - for (i = 0; i < ARRAY_SIZE(bitmap); i++) { - unsigned long map = bitmap[i]; + for (i = 0; i < bitmap_size; i++) { + unsigned long map = state->dirty_bitmap[i]; while (map != 0) { j = ctzl(map); map &= ~(1ul << j); @@ -678,6 +683,8 @@ static void xen_log_stop(MemoryListener *listener, MemoryRegionSection *section, if (old & ~new & (1 << DIRTY_MEMORY_VGA)) { state->log_for_dirtybit = NULL; + g_free(state->dirty_bitmap); + state->dirty_bitmap = NULL; /* Disable dirty bit tracking */ xen_track_dirty_vram(xen_domid, 0, 0, NULL); } |