From: Kevin Wolf <kwolf@redhat.com>
To: qemu-devel@nongnu.org
Cc: kwolf@redhat.com
Subject: [Qemu-devel] [PULL 24/32] docs/qcow2: Correct refcount_block_entries
Date: Thu, 23 Oct 2014 22:42:31 +0200 [thread overview]
Message-ID: <1414096959-14682-25-git-send-email-kwolf@redhat.com> (raw)
In-Reply-To: <1414096959-14682-1-git-send-email-kwolf@redhat.com>
From: Max Reitz <mreitz@redhat.com>
A refblock entry may have a different size than 16 bits, it may even be
smaller than a byte. Correct the refcount_block_entries calculation
accordingly.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
---
docs/specs/qcow2.txt | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/docs/specs/qcow2.txt b/docs/specs/qcow2.txt
index cfbc8b0..0a878aa 100644
--- a/docs/specs/qcow2.txt
+++ b/docs/specs/qcow2.txt
@@ -183,7 +183,7 @@ blocks and are exactly one cluster in size.
Given a offset into the image file, the refcount of its cluster can be obtained
as follows:
- refcount_block_entries = (cluster_size / sizeof(uint16_t))
+ refcount_block_entries = (cluster_size * 8 / refcount_bits)
refcount_block_index = (offset / cluster_size) % refcount_block_entries
refcount_table_index = (offset / cluster_size) / refcount_block_entries
--
1.8.3.1
next prev parent reply other threads:[~2014-10-23 20:43 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-23 20:42 [Qemu-devel] [PULL 00/32] Block patches Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 01/32] MAINTAINERS: add aio to block layer Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 02/32] MAINTAINERS: qemu-iotests belongs to the " Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 03/32] MAINTAINERS: add the image fuzzer " Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 04/32] block/vdi: Use {DIV_,}ROUND_UP Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 05/32] block: qemu-iotests change _supported_proto to file once more Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 06/32] block: Add qemu_{,try_}blockalign0() Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 07/32] qcow2: Calculate refcount block entry count Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 08/32] qcow2: Fix leaks in dirty images Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 09/32] qcow2: Split qcow2_check_refcounts() Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 10/32] qcow2: Use sizeof(**refcount_table) Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 11/32] qcow2: Pull check_refblocks() up Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 12/32] qcow2: Use int64_t for in-memory reftable size Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 13/32] qcow2: Split fail code in L1 and L2 checks Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 14/32] qcow2: Let inc_refcounts() return -errno Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 15/32] qcow2: Let inc_refcounts() resize the reftable Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 16/32] qcow2: Reuse refcount table in calculate_refcounts() Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 17/32] qcow2: Fix refcount blocks beyond image end Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 18/32] qcow2: Do not perform potentially damaging repairs Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 19/32] qcow2: Rebuild refcount structure during check Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 20/32] qcow2: Clean up after refcount rebuild Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 21/32] iotests: Fix test outputs Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 22/32] iotests: Add test for potentially damaging repairs Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 23/32] qcow2: Drop REFCOUNT_SHIFT Kevin Wolf
2014-10-23 20:42 ` Kevin Wolf [this message]
2014-10-23 20:42 ` [Qemu-devel] [PULL 25/32] docs/qcow2: Limit refcount_order to [0, 6] Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 26/32] block: Respect underlying file's EOF Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 27/32] qemu-io: Respect early image end for map Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 28/32] iotests: Add test for map commands Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 29/32] qcow2: Do not overflow when writing an L1 sector Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 30/32] iotests: Add test for qcow2 L1 table update Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 31/32] block: char devices on FreeBSD are not behind a pager Kevin Wolf
2014-10-23 20:42 ` [Qemu-devel] [PULL 32/32] qemu-img: Print error if check failed Kevin Wolf
2014-10-24 11:38 ` [Qemu-devel] [PULL 00/32] Block patches Peter Maydell
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