* [Qemu-devel] [PATCH] qcow2: add update refcount table realization for update_refcount
@ 2014-08-31 17:22 Jun Li
2014-09-01 10:56 ` Jun Li
0 siblings, 1 reply; 2+ messages in thread
From: Jun Li @ 2014-08-31 17:22 UTC (permalink / raw)
To: qemu-devel; +Cc: kwolf, famz, juli, Jun Li, stefanha
When every item of refcount block is NULL, free refcount block and reset the
corresponding item of refcount table with NULL.
Signed-off-by: Jun Li <junmuzi@gmail.com>
---
block/qcow2-refcount.c | 31 +++++++++++++++++++++++++++++++
1 file changed, 31 insertions(+)
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
index 43665b8..b53a000 100644
--- a/block/qcow2-refcount.c
+++ b/block/qcow2-refcount.c
@@ -586,6 +586,37 @@ static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs,
if (refcount == 0 && s->discard_passthrough[type]) {
update_refcount_discard(bs, cluster_offset, s->cluster_size);
}
+
+ /* When refcount block is NULL, update refcount table */
+ if (block_index == 0) {
+ int k = block_index;
+ int refcount_block_entries = s->cluster_size / sizeof(uint16_t);
+ for (k = 1; k < refcount_block_entries; k++) {
+ if (refcount_block[++k] != cpu_to_be16(refcount)) {
+ break;
+ }
+ }
+
+ if (k == refcount_block_entries) {
+ qemu_vfree(refcount_block);
+ /* update refcount table */
+ unsigned int refcount_table_index;
+ uint64_t data64 = cpu_to_be64(0);
+ refcount_table_index = cluster_index >> (s->cluster_bits -
+ REFCOUNT_SHIFT);
+ ret = bdrv_pwrite_sync(bs->file,
+ s->refcount_table_offset +
+ refcount_table_index *
+ sizeof(uint64_t),
+ &data64, sizeof(data64));
+ if (ret < 0) {
+ goto fail;
+ }
+
+ s->refcount_table[refcount_table_index] = data64;
+
+ }
+ }
}
ret = 0;
--
1.9.3
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [Qemu-devel] [PATCH] qcow2: add update refcount table realization for update_refcount
2014-08-31 17:22 [Qemu-devel] [PATCH] qcow2: add update refcount table realization for update_refcount Jun Li
@ 2014-09-01 10:56 ` Jun Li
0 siblings, 0 replies; 2+ messages in thread
From: Jun Li @ 2014-09-01 10:56 UTC (permalink / raw)
To: qemu-devel; +Cc: kwolf, famz, juli, stefanha
Please ignore it. You could review v2 of this patch directly. Thx.
On Mon, 09/01 01:22, Jun Li wrote:
> When every item of refcount block is NULL, free refcount block and reset the
> corresponding item of refcount table with NULL.
>
> Signed-off-by: Jun Li <junmuzi@gmail.com>
> ---
> block/qcow2-refcount.c | 31 +++++++++++++++++++++++++++++++
> 1 file changed, 31 insertions(+)
>
> diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c
> index 43665b8..b53a000 100644
> --- a/block/qcow2-refcount.c
> +++ b/block/qcow2-refcount.c
> @@ -586,6 +586,37 @@ static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs,
> if (refcount == 0 && s->discard_passthrough[type]) {
> update_refcount_discard(bs, cluster_offset, s->cluster_size);
> }
> +
> + /* When refcount block is NULL, update refcount table */
> + if (block_index == 0) {
> + int k = block_index;
> + int refcount_block_entries = s->cluster_size / sizeof(uint16_t);
> + for (k = 1; k < refcount_block_entries; k++) {
> + if (refcount_block[++k] != cpu_to_be16(refcount)) {
> + break;
> + }
> + }
> +
> + if (k == refcount_block_entries) {
> + qemu_vfree(refcount_block);
> + /* update refcount table */
> + unsigned int refcount_table_index;
> + uint64_t data64 = cpu_to_be64(0);
> + refcount_table_index = cluster_index >> (s->cluster_bits -
> + REFCOUNT_SHIFT);
> + ret = bdrv_pwrite_sync(bs->file,
> + s->refcount_table_offset +
> + refcount_table_index *
> + sizeof(uint64_t),
> + &data64, sizeof(data64));
> + if (ret < 0) {
> + goto fail;
> + }
> +
> + s->refcount_table[refcount_table_index] = data64;
> +
> + }
> + }
> }
>
> ret = 0;
> --
> 1.9.3
>
^ permalink raw reply [flat|nested] 2+ messages in thread
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