Add a cdrom size checker for OVF ds to ds-identify

With a large size ISO file attached to iso dev, ds-identify might
grep it entirely if iso dev is ISO9660, it takes very long time to
start OS.

Resolve this by:

- Adding a checker to read the ISO size (from sysfs).  If
the size of the ISO filesystem is > 10MiB then the ISO will be
ignored (logged as oversized).

- Move the ovf vmware guest customization checker to be
ahead of cdrom ovf checker, so no need check the ISO size if vmware
guest customization is enabled.

LP: #1806701

1 files changed, 26 insertions, 13 deletions

diff --git a/tools/ds-identify b/tools/ds-identify
index e16708f6..0305e361 100755
--- a/tools/ds-identify
+++ b/tools/ds-identify
@@ -766,10 +766,34 @@ is_cdrom_ovf() {
         config-2|CONFIG-2|rd_rdfe_stable*|cidata|CIDATA) return 1;;
     esac
 
+    # skip device which size is 10MB or larger
+    local size="" sfile="${PATH_SYS_CLASS_BLOCK}/${dev##*/}/size"
+    [ -f "$sfile" ] || return 1
+    read size <"$sfile" || { warn "failed reading from $sfile"; return 1; }
+    # size is in 512 byte units. so convert to MB (integer division)
+    if [ $((size/2048)) -ge 10 ]; then
+        debug 2 "$dev: size $((size/2048))MB is considered too large for OVF"
+        return 1
+    fi
+
     local idstr="http://schemas.dmtf.org/ovf/environment/1"
     grep --quiet --ignore-case "$idstr" "${PATH_ROOT}$dev"
 }
 
+has_ovf_cdrom() {
+    # DI_ISO9660_DEVS is <device>=label,<device>=label2
+    # like /dev/sr0=OVF-TRANSPORT,/dev/other=with spaces
+    if [ "${DI_ISO9660_DEVS#${UNAVAILABLE}:}" = "${DI_ISO9660_DEVS}" ]; then
+        local oifs="$IFS"
+        # shellcheck disable=2086
+        { IFS=","; set -- ${DI_ISO9660_DEVS}; IFS="$oifs"; }
+        for tok in "$@"; do
+            is_cdrom_ovf "${tok%%=*}" "${tok#*=}" && return 0
+        done
+    fi
+    return 1
+}
+
 dscheck_OVF() {
     check_seed_dir ovf ovf-env.xml && return "${DS_FOUND}"
 
@@ -780,20 +804,9 @@ dscheck_OVF() {
 
     ovf_vmware_transport_guestinfo && return "${DS_FOUND}"
 
-    # DI_ISO9660_DEVS is <device>=label,<device>=label2
-    # like /dev/sr0=OVF-TRANSPORT,/dev/other=with spaces
-    if [ "${DI_ISO9660_DEVS#${UNAVAILABLE}:}" = "${DI_ISO9660_DEVS}" ]; then
-        local oifs="$IFS"
-        # shellcheck disable=2086
-        { IFS=","; set -- ${DI_ISO9660_DEVS}; IFS="$oifs"; }
-        for tok in "$@"; do
-            is_cdrom_ovf "${tok%%=*}" "${tok#*=}" && return $DS_FOUND
-        done
-    fi
+    has_ovf_cdrom && return "${DS_FOUND}"
 
-    if ovf_vmware_guest_customization; then
-        return ${DS_FOUND}
-    fi
+    ovf_vmware_guest_customization && return "${DS_FOUND}"
 
     return ${DS_NOT_FOUND}
 }