From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52253) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YODJ5-0002bf-3u for qemu-devel@nongnu.org; Wed, 18 Feb 2015 17:41:23 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YODIy-0001dU-DL for qemu-devel@nongnu.org; Wed, 18 Feb 2015 17:41:23 -0500 Received: from mx1.redhat.com ([209.132.183.28]:54942) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YODIy-0001cv-6j for qemu-devel@nongnu.org; Wed, 18 Feb 2015 17:41:16 -0500 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id t1IMfFDo008999 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Wed, 18 Feb 2015 17:41:15 -0500 From: Max Reitz Date: Wed, 18 Feb 2015 17:40:58 -0500 Message-Id: <1424299260-1763-14-git-send-email-mreitz@redhat.com> In-Reply-To: <1424299260-1763-1-git-send-email-mreitz@redhat.com> References: <1424299260-1763-1-git-send-email-mreitz@redhat.com> Subject: [Qemu-devel] [PATCH v7 23/25] qcow2: Invoke refcount order amendment function List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , Stefan Hajnoczi , Max Reitz Make use of qcow2_change_refcount_order() to support changing the refcount order with qemu-img amend. Signed-off-by: Max Reitz Reviewed-by: Eric Blake Reviewed-by: Stefan Hajnoczi --- block/qcow2.c | 44 +++++++++++++++++++++++++++++++++++--------- 1 file changed, 35 insertions(+), 9 deletions(-) diff --git a/block/qcow2.c b/block/qcow2.c index 8931132..42df2b5 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -2617,13 +2617,7 @@ static int qcow2_downgrade(BlockDriverState *bs, int target_version, } if (s->refcount_order != 4) { - /* we would have to convert the image to a refcount_order == 4 image - * here; however, since qemu (at the time of writing this) does not - * support anything different than 4 anyway, there is no point in doing - * so right now; however, we should error out (if qemu supports this in - * the future and this code has not been adapted) */ - error_report("qcow2_downgrade: Image refcount orders other than 4 are " - "currently not supported."); + error_report("compat=0.10 requires refcount_bits=16"); return -ENOTSUP; } @@ -2671,6 +2665,7 @@ typedef enum Qcow2AmendOperation { * invocation from an operation change */ QCOW2_NO_OPERATION = 0, + QCOW2_CHANGING_REFCOUNT_ORDER, QCOW2_DOWNGRADING, } Qcow2AmendOperation; @@ -2746,6 +2741,7 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, const char *compat = NULL; uint64_t cluster_size = s->cluster_size; bool encrypt; + int refcount_bits = s->refcount_bits; int ret; QemuOptDesc *desc = opts->list->desc; Qcow2AmendHelperCBInfo helper_cb_info; @@ -2796,8 +2792,16 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, lazy_refcounts = qemu_opt_get_bool(opts, BLOCK_OPT_LAZY_REFCOUNTS, lazy_refcounts); } else if (!strcmp(desc->name, BLOCK_OPT_REFCOUNT_BITS)) { - error_report("Cannot change refcount entry width"); - return -ENOTSUP; + refcount_bits = qemu_opt_get_number(opts, BLOCK_OPT_REFCOUNT_BITS, + refcount_bits); + + if (refcount_bits <= 0 || refcount_bits > 64 || + !is_power_of_2(refcount_bits)) + { + error_report("Refcount width must be a power of two and may " + "not exceed 64 bits"); + return -EINVAL; + } } else { /* if this point is reached, this probably means a new option was * added without having it covered here */ @@ -2811,6 +2815,7 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, .original_status_cb = status_cb, .original_cb_opaque = cb_opaque, .total_operations = (new_version < old_version) + + (s->refcount_bits != refcount_bits) }; /* Upgrade first (some features may require compat=1.1) */ @@ -2823,6 +2828,27 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, } } + if (s->refcount_bits != refcount_bits) { + int refcount_order = ffs(refcount_bits) - 1; + Error *local_error = NULL; + + if (new_version < 3 && refcount_bits != 16) { + error_report("Different refcount widths than 16 bits require " + "compatibility level 1.1 or above (use compat=1.1 or " + "greater)"); + return -EINVAL; + } + + helper_cb_info.current_operation = QCOW2_CHANGING_REFCOUNT_ORDER; + ret = qcow2_change_refcount_order(bs, refcount_order, + &qcow2_amend_helper_cb, + &helper_cb_info, &local_error); + if (ret < 0) { + qerror_report_err(local_error); + return ret; + } + } + if (backing_file || backing_format) { ret = qcow2_change_backing_file(bs, backing_file ?: bs->backing_file, backing_format ?: bs->backing_format); -- 2.1.0