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| author | Robert Morris <rtm@csail.mit.edu> | 2019-07-23 12:17:17 -0400 |
|---|---|---|
| committer | Robert Morris <rtm@csail.mit.edu> | 2019-07-23 12:17:17 -0400 |
| commit | 54178ad94d758e557bfa369b7f137e2844e030e1 (patch) | |
| tree | cc2446a7d55d35e30f12f26e44aef68d285bfc91 /kernel/virtio_disk.c | |
| parent | 55bc96d4190e40704fb5e447cef9597b08b8f088 (diff) | |
| download | xv6-labs-2022-54178ad94d758e557bfa369b7f137e2844e030e1.tar.xz xv6-labs-2022-54178ad94d758e557bfa369b7f137e2844e030e1.zip | |
simplify kernel mapping calls
Diffstat (limited to 'kernel/virtio_disk.c')
| -rw-r--r-- | kernel/virtio_disk.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/kernel/virtio_disk.c b/kernel/virtio_disk.c index 6620037..3406478 100644 --- a/kernel/virtio_disk.c +++ b/kernel/virtio_disk.c @@ -199,6 +199,8 @@ virtio_disk_rw(struct buf *b) buf0.reserved = 0; buf0.sector = sector; + // buf0 is on a kernel stack, which is not direct mapped, + // thus the call to kernelpa(). desc[idx[0]].addr = (uint64) kernelpa((uint64) &buf0); desc[idx[0]].len = sizeof(buf0); desc[idx[0]].flags = VRING_DESC_F_NEXT; |