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pve-qemu-qoup/debian/patches/pve/0012-PVE-Up-qemu-img-dd-add-n-skip_create.patch
Fiona Ebner 5b15e2ecaf update submodule and patches to 7.1.0 
Notable changes:
* The only big change is the switch to using a custom QIOChannel for
  savevm-async, because the previously used QEMUFileOps was dropped.

  Changes to the current implementation:

  * Switch to vector based methods as required for an IO channel. For
    short reads the passed-in IO vector is stuffed with zeroes at the
    end, just to be sure.

  * For reading: The documentation in include/io/channel.h states that
    at least one byte should be read, so also error out when whe are
    at the very end instead of returning 0.

  * For reading: Fix off-by-one error when request goes beyond end.

    The wrong code piece was:
    if ((pos + size) > maxlen) {
        size = maxlen - pos - 1;
    }

    Previously, the last byte would not be read. It's actually
    possible to get a snapshot .raw file that has content all the way
    up the final 512 byte (= BDRV_SECTOR_SIZE) boundary without any
    trailing zero bytes (I wrote a script to do it).

    Luckily, it didn't cause a real issue, because qemu_loadvm_state()
    is not interested in the final (i.e. QEMU_VM_VMDESCRIPTION)
    section. The buffer for reading it is simply freed up afterwards
    and the function will assume that it read the whole section, even
    if that's not the case.

  * For writing: Make use of the generated blk_pwritev() wrapper
    instead of manually wrapping the coroutine to simplify and save a
    few lines.

* Adapt to changed interfaces for blk_{pread,pwrite}:
  * a9262f551e ("block: Change blk_{pread,pwrite}() param order")
  * 3b35d4542c ("block: Add a 'flags' param to blk_pread()")
  * bf5b16fa40 ("block: Make blk_{pread,pwrite}() return 0 on success")
  Those changes especially affected the qemu-img dd patches, because
  the context also changed, but also some of our block drivers used
  the functions.

* Drop qemu-common.h include: it got renamed after essentially
  everything was moved to other headers. The only remaining user I
  could find for things dropped from the header between 7.0 and 7.1
  was qemu_get_vm_name() in the iscsi-initiatorname patch, but it
  already includes the header to which the function was moved.

Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
2022-10-14 14:52:29 +02:00

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From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Alexandre Derumier <aderumier@odiso.com>
Date: Mon, 6 Apr 2020 12:16:42 +0200
Subject: [PATCH] PVE: [Up] qemu-img dd: add -n skip_create
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
[FE: fix getopt-string + add documentation]
Signed-off-by: Fabian Ebner <f.ebner@proxmox.com>
---
docs/tools/qemu-img.rst | 11 ++++++++++-
qemu-img-cmds.hx | 4 ++--
qemu-img.c | 23 ++++++++++++++---------
3 files changed, 26 insertions(+), 12 deletions(-)
diff --git a/docs/tools/qemu-img.rst b/docs/tools/qemu-img.rst
index 85a6e05b35..699229eef6 100644
--- a/docs/tools/qemu-img.rst
+++ b/docs/tools/qemu-img.rst
@@ -208,6 +208,10 @@ Parameters to convert subcommand:
Parameters to dd subcommand:
+.. option:: -n
+
+ Skip the creation of the target volume
+
.. program:: qemu-img-dd
.. option:: bs=BLOCK_SIZE
@@ -488,7 +492,7 @@ Command description:
it doesn't need to be specified separately in this case.
-.. option:: dd [--image-opts] [-U] [-f FMT] [-O OUTPUT_FMT] [bs=BLOCK_SIZE] [count=BLOCKS] [skip=BLOCKS] if=INPUT of=OUTPUT
+.. option:: dd [--image-opts] [-U] [-f FMT] [-O OUTPUT_FMT] [-n] [bs=BLOCK_SIZE] [count=BLOCKS] [skip=BLOCKS] if=INPUT of=OUTPUT
dd copies from *INPUT* file to *OUTPUT* file converting it from
*FMT* format to *OUTPUT_FMT* format.
@@ -499,6 +503,11 @@ Command description:
The size syntax is similar to :manpage:`dd(1)`'s size syntax.
+ If the ``-n`` option is specified, the target volume creation will be
+ skipped. This is useful for formats such as ``rbd`` if the target
+ volume has already been created with site specific options that cannot
+ be supplied through ``qemu-img``.
+
.. option:: info [--object OBJECTDEF] [--image-opts] [-f FMT] [--output=OFMT] [--backing-chain] [-U] FILENAME
Give information about the disk image *FILENAME*. Use it in
diff --git a/qemu-img-cmds.hx b/qemu-img-cmds.hx
index d1616c045a..b5b0bb4467 100644
--- a/qemu-img-cmds.hx
+++ b/qemu-img-cmds.hx
@@ -58,9 +58,9 @@ SRST
ERST
DEF("dd", img_dd,
- "dd [--image-opts] [-U] [-f fmt] [-O output_fmt] [bs=block_size] [count=blocks] [skip=blocks] [osize=output_size] if=input of=output")
+ "dd [--image-opts] [-U] [-f fmt] [-O output_fmt] [-n] [bs=block_size] [count=blocks] [skip=blocks] [osize=output_size] if=input of=output")
SRST
-.. option:: dd [--image-opts] [-U] [-f FMT] [-O OUTPUT_FMT] [bs=BLOCK_SIZE] [count=BLOCKS] [skip=BLOCKS] [osize=OUTPUT_SIZE] if=INPUT of=OUTPUT
+.. option:: dd [--image-opts] [-U] [-f FMT] [-O OUTPUT_FMT] [-n] [bs=BLOCK_SIZE] [count=BLOCKS] [skip=BLOCKS] [osize=OUTPUT_SIZE] if=INPUT of=OUTPUT
ERST
DEF("info", img_info,
diff --git a/qemu-img.c b/qemu-img.c
index 14594d44b6..c6b4a5567d 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -4951,7 +4951,7 @@ static int img_dd(int argc, char **argv)
const char *fmt = NULL;
int64_t size = 0, readsize = 0;
int64_t block_count = 0, out_pos, in_pos;
- bool force_share = false;
+ bool force_share = false, skip_create = false;
struct DdInfo dd = {
.flags = 0,
.count = 0,
@@ -4989,7 +4989,7 @@ static int img_dd(int argc, char **argv)
{ 0, 0, 0, 0 }
};
- while ((c = getopt_long(argc, argv, ":hf:O:U", long_options, NULL))) {
+ while ((c = getopt_long(argc, argv, ":hf:O:Un", long_options, NULL))) {
if (c == EOF) {
break;
}
@@ -5009,6 +5009,9 @@ static int img_dd(int argc, char **argv)
case 'h':
help();
break;
+ case 'n':
+ skip_create = true;
+ break;
case 'U':
force_share = true;
break;
@@ -5139,13 +5142,15 @@ static int img_dd(int argc, char **argv)
size - in.bsz * in.offset, &error_abort);
}
- ret = bdrv_create(drv, out.filename, opts, &local_err);
- if (ret < 0) {
- error_reportf_err(local_err,
- "%s: error while creating output image: ",
- out.filename);
- ret = -1;
- goto out;
+ if (!skip_create) {
+ ret = bdrv_create(drv, out.filename, opts, &local_err);
+ if (ret < 0) {
+ error_reportf_err(local_err,
+ "%s: error while creating output image: ",
+ out.filename);
+ ret = -1;
+ goto out;
+ }
}
/* TODO, we can't honour --image-opts for the target,
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