[PATCH v3 3/8] virsh: Track if vol-upload or vol-download work over a block device

We can't use virFileInData() with block devices, but we can emulate being in data section all the time (vol-upload case). Alternatively, we can't just lseek() beyond EOF with block devices to create a hole, we will have to write zeroes (vol-download case). But to decide we need to know if the FD we are reading data from / writing data to is a block device. Store this information in _virshStreamCallbackData. Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; Reviewed-by: Peter Krempa <pkrempa(a)redhat.com&gt; --- tools/virsh-util.h | 1 + tools/virsh-volume.c | 14 ++++++++++++++ 2 files changed, 15 insertions(+) diff --git a/tools/virsh-util.h b/tools/virsh-util.h index 72653d9735..9ef28cfe0a 100644 --- a/tools/virsh-util.h +++ b/tools/virsh-util.h @@ -72,6 +72,7 @@ typedef virshStreamCallbackData *virshStreamCallbackDataPtr; struct _virshStreamCallbackData { vshControl *ctl; int fd; + bool isBlock; }; int diff --git a/tools/virsh-volume.c b/tools/virsh-volume.c index d29db6c38d..374bde4318 100644 --- a/tools/virsh-volume.c +++ b/tools/virsh-volume.c @@ -676,6 +676,7 @@ cmdVolUpload(vshControl *ctl, const vshCmd *cmd) virshControlPtr priv = ctl->privData; unsigned int flags = 0; virshStreamCallbackData cbData; + struct stat sb; if (vshCommandOptULongLong(ctl, cmd, "offset", &offset) < 0) return false; @@ -694,8 +695,14 @@ cmdVolUpload(vshControl *ctl, const vshCmd *cmd) goto cleanup; } + if (fstat(fd, &sb) < 0) { + vshError(ctl, _("unable to stat %s"), file); + goto cleanup; + } + cbData.ctl = ctl; cbData.fd = fd; + cbData.isBlock = !!S_ISBLK(sb.st_mode); if (vshCommandOptBool(cmd, "sparse")) flags |= VIR_STORAGE_VOL_UPLOAD_SPARSE_STREAM; @@ -792,6 +799,7 @@ cmdVolDownload(vshControl *ctl, const vshCmd *cmd) virshControlPtr priv = ctl->privData; virshStreamCallbackData cbData; unsigned int flags = 0; + struct stat sb; if (vshCommandOptULongLong(ctl, cmd, "offset", &offset) < 0) return false; @@ -818,8 +826,14 @@ cmdVolDownload(vshControl *ctl, const vshCmd *cmd) created = true; } + if (fstat(fd, &sb) < 0) { + vshError(ctl, _("unable to stat %s"), file); + goto cleanup; + } + cbData.ctl = ctl; cbData.fd = fd; + cbData.isBlock = !!S_ISBLK(sb.st_mode); if (!(st = virStreamNew(priv->conn, 0))) { vshError(ctl, _("cannot create a new stream")); -- 2.26.2