aboutsummaryrefslogtreecommitdiff
path: root/hw/pci
diff options
context:
space:
mode:
authorDongli Zhang <dongli.zhang@oracle.com>2018-12-17 07:34:39 +0800
committerMichael S. Tsirkin <mst@redhat.com>2019-01-14 19:31:04 -0500
commit17323e8b689a1f6d1b711df034e9ee3a88ff27ba (patch)
tree1a8873d5474b1d32afe630ba049e12c8e7d2905e /hw/pci
parentb9731850d746e528d317097f907f27116798d7fe (diff)
msix: make pba size math more uniform
In msix_exclusive_bar the bar_pba_size is more than what the pba is expected to have, although this never affects the bar size. Specifically, the math in msix_init_exclusive_bar allocates too much memory in some cases. For example consider nentries = 8. msix_exclusive_bar will give us bar_pba_size = 16. So 16 bytes. However 8 bytes would be enough - this is all that the spec requires. So in practice bar_pba_size sometimes allocates an extra 8 bytes but never more. Since each MSIX entry size is 16 bytes, and since we make sure that table+pba is a power of two, this always leaves a multiple of 16 bytes for the PBA, so extra 8 bytes have no effect. However, its ugly to have pba size temporary variable have an incorrect value. For consistency switch to the formula used in msix_init. Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'hw/pci')
-rw-r--r--hw/pci/msix.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/hw/pci/msix.c b/hw/pci/msix.c
index c7bdbeda9e..4e336416a7 100644
--- a/hw/pci/msix.c
+++ b/hw/pci/msix.c
@@ -345,7 +345,7 @@ int msix_init_exclusive_bar(PCIDevice *dev, unsigned short nentries,
char *name;
uint32_t bar_size = 4096;
uint32_t bar_pba_offset = bar_size / 2;
- uint32_t bar_pba_size = (nentries / 8 + 1) * 8;
+ uint32_t bar_pba_size = QEMU_ALIGN_UP(nentries, 64) / 8;
/*
* Migration compatibility dictates that this remains a 4k