On 2019-04-24 15:49, Sam Eiderman wrote:
Commit b0651b8c246d ("vmdk: Move l1_size check into vmdk_add_extent")
extended the l1_size check from VMDK4 to VMDK3 but did not update the
default coverage in the moved comment.
The previous vmdk4 calculation:
(512 * 1024 * 1024) * 512(l2 entries) * 65536(grain) = 16PB
The added vmdk3 calculation:
(512 * 1024 * 1024) * 4096(l2 entries) * 512(grain) = 1PB
Adding the calculation of vmdk3 to the comment.
In any case, VMware does not offer virtual disks more than 2TB for
vmdk4/vmdk3 or 64TB for the new undocumented seSparse format which is
not implemented yet in qemu.
Reviewed-by: Karl Heubaum <karl.heub...@oracle.com>
Reviewed-by: Eyal Moscovici <eyal.moscov...@oracle.com>
Reviewed-by: Liran Alon <liran.a...@oracle.com>
Reviewed-by: Arbel Moshe <arbel.mo...@oracle.com>
Signed-off-by: Sam Eiderman <shmuel.eider...@oracle.com>
---
block/vmdk.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/block/vmdk.c b/block/vmdk.c
index de8cb859f8..fc7378da78 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -426,10 +426,15 @@ static int vmdk_add_extent(BlockDriverState *bs,
return -EFBIG;
}
if (l1_size > 512 * 1024 * 1024) {
- /* Although with big capacity and small l1_entry_sectors, we
can get a
+ /*
+ * Although with big capacity and small l1_entry_sectors, we
can get a
* big l1_size, we don't want unbounded value to allocate the
table.
- * Limit it to 512M, which is 16PB for default cluster and L2
table
- * size */
+ * Limit it to 512M, which is:
+ * 16PB - for default "Hosted Sparse Extent" (VMDK4)
+ * cluster size: 64KB, L2 table size: 512 entries
+ * 1PB - for default "ESXi Host Sparse Extent"
(VMDK3/vmfsSparse)
+ * cluster size: 512B, L2 table size: 4096 entries
+ */
error_setg(errp, "L1 size too big");
return -EFBIG;
}
The calculation of VMDK3 can be verified in end of page No.9 of the spec
(https://www.vmware.com/support/developer/vddk/vmdk_50_technote.pdf).
Also the VMDK4 can be checked in the section Grain Table and Grain in
page No.8 of the spec.
Reviewed-by: yuchenlin <yuchen...@synology.com>
