From e01a2ccba2a784caad5192f8d1e4b37ae1d65bed Mon Sep 17 00:00:00 2001

From: Max Reitz <mreitz@redhat.com>

Date: Mon, 18 Jun 2018 14:59:38 +0200

Subject: [PATCH 04/89] block: Add Error parameter to bdrv_amend_options

RH-Author: Max Reitz <mreitz@redhat.com>

Message-id: <20180618145943.4489-3-mreitz@redhat.com>

Patchwork-id: 80755

O-Subject: [RHV-7.6 qemu-kvm-rhev PATCH 2/7] block: Add Error parameter to bdrv_amend_options

Bugzilla: 1537956

RH-Acked-by: John Snow <jsnow@redhat.com>

RH-Acked-by: Kevin Wolf <kwolf@redhat.com>

RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

Looking at the qcow2 code that is riddled with error_report() calls,

this is really how it should have been from the start.

Along the way, turn the target_version/current_version comparisons at

the beginning of qcow2_downgrade() into assertions (the caller has to

make sure these conditions are met), and rephrase the error message on

using compat=1.1 to get refcount widths other than 16 bits.

Signed-off-by: Max Reitz <mreitz@redhat.com>

Message-id: 20180509210023.20283-3-mreitz@redhat.com

Reviewed-by: Eric Blake <eblake@redhat.com>

Reviewed-by: John Snow <jsnow@redhat.com>

Signed-off-by: Max Reitz <mreitz@redhat.com>

(cherry picked from commit d1402b502691142b9cebadd5cb993dc8858e9071)

Signed-off-by: Max Reitz <mreitz@redhat.com>

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

---

 block.c                    |  8 ++++--

 block/qcow2.c              | 72 ++++++++++++++++++++++++++--------------------

 include/block/block.h      |  3 +-

 include/block/block_int.h  |  3 +-

 qemu-img.c                 |  4 +--

 tests/qemu-iotests/060.out |  4 +--

 tests/qemu-iotests/061.out |  7 -----

 tests/qemu-iotests/080.out |  4 +--

 tests/qemu-iotests/112.out |  5 +---

 9 files changed, 58 insertions(+), 52 deletions(-)

diff --git a/block.c b/block.c

index 982d54e..d991a09 100644

--- a/block.c

+++ b/block.c

@@ -5008,15 +5008,19 @@ void bdrv_remove_aio_context_notifier(BlockDriverState *bs,

 }

 int bdrv_amend_options(BlockDriverState *bs, QemuOpts *opts,

-                       BlockDriverAmendStatusCB *status_cb, void *cb_opaque)

+                       BlockDriverAmendStatusCB *status_cb, void *cb_opaque,

+                       Error **errp)

 {

     if (!bs->drv) {

+        error_setg(errp, "Node is ejected");

         return -ENOMEDIUM;

     }

     if (!bs->drv->bdrv_amend_options) {

+        error_setg(errp, "Block driver '%s' does not support option amendment",

+                   bs->drv->format_name);

         return -ENOTSUP;

     }

-    return bs->drv->bdrv_amend_options(bs, opts, status_cb, cb_opaque);

+    return bs->drv->bdrv_amend_options(bs, opts, status_cb, cb_opaque, errp);

 }

 /* This function will be called by the bdrv_recurse_is_first_non_filter method

diff --git a/block/qcow2.c b/block/qcow2.c

index 26a6a7f..092db81 100644

--- a/block/qcow2.c

+++ b/block/qcow2.c

@@ -4039,22 +4039,21 @@ static int qcow2_load_vmstate(BlockDriverState *bs, QEMUIOVector *qiov,

  * have to be removed.

  */

 static int qcow2_downgrade(BlockDriverState *bs, int target_version,

-                           BlockDriverAmendStatusCB *status_cb, void *cb_opaque)

+                           BlockDriverAmendStatusCB *status_cb, void *cb_opaque,

+                           Error **errp)

 {

     BDRVQcow2State *s = bs->opaque;

     int current_version = s->qcow_version;

     int ret;

-    if (target_version == current_version) {

-        return 0;

-    } else if (target_version > current_version) {

-        return -EINVAL;

-    } else if (target_version != 2) {

-        return -EINVAL;

-    }

+    /* This is qcow2_downgrade(), not qcow2_upgrade() */

+    assert(target_version < current_version);

+

+    /* There are no other versions (now) that you can downgrade to */

+    assert(target_version == 2);

     if (s->refcount_order != 4) {

-        error_report("compat=0.10 requires refcount_bits=16");

+        error_setg(errp, "compat=0.10 requires refcount_bits=16");

         return -ENOTSUP;

     }

@@ -4062,6 +4061,7 @@ static int qcow2_downgrade(BlockDriverState *bs, int target_version,

     if (s->incompatible_features & QCOW2_INCOMPAT_DIRTY) {

         ret = qcow2_mark_clean(bs);

         if (ret < 0) {

+            error_setg_errno(errp, -ret, "Failed to make the image clean");

             return ret;

         }

     }

@@ -4071,6 +4071,8 @@ static int qcow2_downgrade(BlockDriverState *bs, int target_version,

      * best thing to do anyway */

     if (s->incompatible_features) {

+        error_setg(errp, "Cannot downgrade an image with incompatible features "

+                   "%#" PRIx64 " set", s->incompatible_features);

         return -ENOTSUP;

     }

@@ -4084,6 +4086,7 @@ static int qcow2_downgrade(BlockDriverState *bs, int target_version,

     ret = qcow2_expand_zero_clusters(bs, status_cb, cb_opaque);

     if (ret < 0) {

+        error_setg_errno(errp, -ret, "Failed to turn zero into data clusters");

         return ret;

     }

@@ -4091,6 +4094,7 @@ static int qcow2_downgrade(BlockDriverState *bs, int target_version,

     ret = qcow2_update_header(bs);

     if (ret < 0) {

         s->qcow_version = current_version;

+        error_setg_errno(errp, -ret, "Failed to update the image header");

         return ret;

     }

     return 0;

@@ -4168,7 +4172,8 @@ static void qcow2_amend_helper_cb(BlockDriverState *bs,

 static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,

                                BlockDriverAmendStatusCB *status_cb,

-                               void *cb_opaque)

+                               void *cb_opaque,

+                               Error **errp)

 {

     BDRVQcow2State *s = bs->opaque;

     int old_version = s->qcow_version, new_version = old_version;

@@ -4180,7 +4185,6 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,

     bool encrypt;

     int encformat;

     int refcount_bits = s->refcount_bits;

-    Error *local_err = NULL;

     int ret;

     QemuOptDesc *desc = opts->list->desc;

     Qcow2AmendHelperCBInfo helper_cb_info;

@@ -4201,11 +4205,11 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,

             } else if (!strcmp(compat, "1.1")) {

                 new_version = 3;

             } else {

-                error_report("Unknown compatibility level %s", compat);

+                error_setg(errp, "Unknown compatibility level %s", compat);

                 return -EINVAL;

             }

         } else if (!strcmp(desc->name, BLOCK_OPT_PREALLOC)) {

-            error_report("Cannot change preallocation mode");

+            error_setg(errp, "Cannot change preallocation mode");

             return -ENOTSUP;

         } else if (!strcmp(desc->name, BLOCK_OPT_SIZE)) {

             new_size = qemu_opt_get_size(opts, BLOCK_OPT_SIZE, 0);

@@ -4218,7 +4222,8 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,

                                         !!s->crypto);

             if (encrypt != !!s->crypto) {

-                error_report("Changing the encryption flag is not supported");

+                error_setg(errp,

+                           "Changing the encryption flag is not supported");

                 return -ENOTSUP;

             }

         } else if (!strcmp(desc->name, BLOCK_OPT_ENCRYPT_FORMAT)) {

@@ -4226,17 +4231,19 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,

                 qemu_opt_get(opts, BLOCK_OPT_ENCRYPT_FORMAT));

             if (encformat != s->crypt_method_header) {

-                error_report("Changing the encryption format is not supported");

+                error_setg(errp,

+                           "Changing the encryption format is not supported");

                 return -ENOTSUP;

             }

         } else if (g_str_has_prefix(desc->name, "encrypt.")) {

-            error_report("Changing the encryption parameters is not supported");

+            error_setg(errp,

+                       "Changing the encryption parameters is not supported");

             return -ENOTSUP;

         } else if (!strcmp(desc->name, BLOCK_OPT_CLUSTER_SIZE)) {

             cluster_size = qemu_opt_get_size(opts, BLOCK_OPT_CLUSTER_SIZE,

                                              cluster_size);

             if (cluster_size != s->cluster_size) {

-                error_report("Changing the cluster size is not supported");

+                error_setg(errp, "Changing the cluster size is not supported");

                 return -ENOTSUP;

             }

         } else if (!strcmp(desc->name, BLOCK_OPT_LAZY_REFCOUNTS)) {

@@ -4249,8 +4256,8 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,

             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");

+                error_setg(errp, "Refcount width must be a power of two and "

+                           "may not exceed 64 bits");

                 return -EINVAL;

             }

         } else {

@@ -4275,6 +4282,7 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,

         ret = qcow2_update_header(bs);

         if (ret < 0) {

             s->qcow_version = old_version;

+            error_setg_errno(errp, -ret, "Failed to update the image header");

             return ret;

         }

     }

@@ -4283,18 +4291,17 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,

         int refcount_order = ctz32(refcount_bits);

         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)");

+            error_setg(errp, "Refcount widths other 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_err);

+                                          &helper_cb_info, errp);

         if (ret < 0) {

-            error_report_err(local_err);

             return ret;

         }

     }

@@ -4304,6 +4311,7 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,

                     backing_file ?: s->image_backing_file,

                     backing_format ?: s->image_backing_format);

         if (ret < 0) {

+            error_setg_errno(errp, -ret, "Failed to change the backing file");

             return ret;

         }

     }

@@ -4311,14 +4319,16 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,

     if (s->use_lazy_refcounts != lazy_refcounts) {

         if (lazy_refcounts) {

             if (new_version < 3) {

-                error_report("Lazy refcounts only supported with compatibility "

-                             "level 1.1 and above (use compat=1.1 or greater)");

+                error_setg(errp, "Lazy refcounts only supported with "

+                           "compatibility level 1.1 and above (use compat=1.1 "

+                           "or greater)");

                 return -EINVAL;

             }

             s->compatible_features |= QCOW2_COMPAT_LAZY_REFCOUNTS;

             ret = qcow2_update_header(bs);

             if (ret < 0) {

                 s->compatible_features &= ~QCOW2_COMPAT_LAZY_REFCOUNTS;

+                error_setg_errno(errp, -ret, "Failed to update the image header");

                 return ret;

             }

             s->use_lazy_refcounts = true;

@@ -4326,6 +4336,7 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,

             /* make image clean first */

             ret = qcow2_mark_clean(bs);

             if (ret < 0) {

+                error_setg_errno(errp, -ret, "Failed to make the image clean");

                 return ret;

             }

             /* now disallow lazy refcounts */

@@ -4333,6 +4344,7 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,

             ret = qcow2_update_header(bs);

             if (ret < 0) {

                 s->compatible_features |= QCOW2_COMPAT_LAZY_REFCOUNTS;

+                error_setg_errno(errp, -ret, "Failed to update the image header");

                 return ret;

             }

             s->use_lazy_refcounts = false;

@@ -4341,17 +4353,15 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,

     if (new_size) {

         BlockBackend *blk = blk_new(BLK_PERM_RESIZE, BLK_PERM_ALL);

-        ret = blk_insert_bs(blk, bs, &local_err);

+        ret = blk_insert_bs(blk, bs, errp);

         if (ret < 0) {

-            error_report_err(local_err);

             blk_unref(blk);

             return ret;

         }

-        ret = blk_truncate(blk, new_size, PREALLOC_MODE_OFF, &local_err);

+        ret = blk_truncate(blk, new_size, PREALLOC_MODE_OFF, errp);

         blk_unref(blk);

         if (ret < 0) {

-            error_report_err(local_err);

             return ret;

         }

     }

@@ -4360,7 +4370,7 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts,

     if (new_version < old_version) {

         helper_cb_info.current_operation = QCOW2_DOWNGRADING;

         ret = qcow2_downgrade(bs, new_version, &qcow2_amend_helper_cb,

-                              &helper_cb_info);

+                              &helper_cb_info, errp);

         if (ret < 0) {

             return ret;

         }

diff --git a/include/block/block.h b/include/block/block.h

index 06cd772..2d17b09 100644

--- a/include/block/block.h

+++ b/include/block/block.h

@@ -343,7 +343,8 @@ int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix);

 typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset,

                                       int64_t total_work_size, void *opaque);

 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts,

-                       BlockDriverAmendStatusCB *status_cb, void *cb_opaque);

+                       BlockDriverAmendStatusCB *status_cb, void *cb_opaque,

+                       Error **errp);

 /* external snapshots */

 bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs,

diff --git a/include/block/block_int.h b/include/block/block_int.h

index c4dd1d4..d913ed1 100644

--- a/include/block/block_int.h

+++ b/include/block/block_int.h

@@ -324,7 +324,8 @@ struct BlockDriver {

     int (*bdrv_amend_options)(BlockDriverState *bs, QemuOpts *opts,

                               BlockDriverAmendStatusCB *status_cb,

-                              void *cb_opaque);

+                              void *cb_opaque,

+                              Error **errp);

     void (*bdrv_debug_event)(BlockDriverState *bs, BlkdebugEvent event);

diff --git a/qemu-img.c b/qemu-img.c

index 2f7c491..e40d6ff 100644

--- a/qemu-img.c

+++ b/qemu-img.c

@@ -3761,10 +3761,10 @@ static int img_amend(int argc, char **argv)

     /* In case the driver does not call amend_status_cb() */

     qemu_progress_print(0.f, 0);

-    ret = bdrv_amend_options(bs, opts, &amend_status_cb, NULL);

+    ret = bdrv_amend_options(bs, opts, &amend_status_cb, NULL, &err;;

     qemu_progress_print(100.f, 0);

     if (ret < 0) {

-        error_report("Error while amending options: %s", strerror(-ret));

+        error_report_err(err);

         goto out;

     }

diff --git a/tests/qemu-iotests/060.out b/tests/qemu-iotests/060.out

index 99234fb..bff023d 100644

--- a/tests/qemu-iotests/060.out

+++ b/tests/qemu-iotests/060.out

@@ -129,7 +129,7 @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864

 wrote 65536/65536 bytes at offset 0

 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)

 qcow2: Marking image as corrupt: L2 table offset 0x42a00 unaligned (L1 index: 0); further corruption events will be suppressed

-qemu-img: Error while amending options: Input/output error

+qemu-img: Failed to turn zero into data clusters: Input/output error

 === Testing unaligned L2 entry ===

@@ -145,7 +145,7 @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864

 wrote 65536/65536 bytes at offset 0

 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)

 qcow2: Marking image as corrupt: Cluster allocation offset 0x52a00 unaligned (L2 offset: 0x40000, L2 index: 0); further corruption events will be suppressed

-qemu-img: Error while amending options: Input/output error

+qemu-img: Failed to turn zero into data clusters: Input/output error

 === Testing unaligned reftable entry ===

diff --git a/tests/qemu-iotests/061.out b/tests/qemu-iotests/061.out

index e857ef9..183f7dd 100644

--- a/tests/qemu-iotests/061.out

+++ b/tests/qemu-iotests/061.out

@@ -358,18 +358,12 @@ No errors were found on the image.

 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864

 qemu-img: Lazy refcounts only supported with compatibility level 1.1 and above (use compat=1.1 or greater)

-qemu-img: Error while amending options: Invalid argument

 qemu-img: Lazy refcounts only supported with compatibility level 1.1 and above (use compat=1.1 or greater)

-qemu-img: Error while amending options: Invalid argument

 qemu-img: Unknown compatibility level 0.42

-qemu-img: Error while amending options: Invalid argument

 qemu-img: Invalid parameter 'foo'

 qemu-img: Changing the cluster size is not supported

-qemu-img: Error while amending options: Operation not supported

 qemu-img: Changing the encryption flag is not supported

-qemu-img: Error while amending options: Operation not supported

 qemu-img: Cannot change preallocation mode

-qemu-img: Error while amending options: Operation not supported

 === Testing correct handling of unset value ===

@@ -377,7 +371,6 @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864

 Should work:

 Should not work:

 qemu-img: Changing the cluster size is not supported

-qemu-img: Error while amending options: Operation not supported

 === Testing zero expansion on inactive clusters ===

diff --git a/tests/qemu-iotests/080.out b/tests/qemu-iotests/080.out

index 4e0f7f7..281c7e0 100644

--- a/tests/qemu-iotests/080.out

+++ b/tests/qemu-iotests/080.out

@@ -65,7 +65,7 @@ wrote 512/512 bytes at offset 0

 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)

 qemu-img: Failed to load snapshot: Snapshot L1 table offset invalid

 qemu-img: Snapshot L1 table offset invalid

-qemu-img: Error while amending options: Invalid argument

+qemu-img: Failed to turn zero into data clusters: Invalid argument

 Failed to flush the refcount block cache: Invalid argument

 write failed: Invalid argument

 qemu-img: Snapshot L1 table offset invalid

@@ -88,7 +88,7 @@ wrote 512/512 bytes at offset 0

 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)

 qemu-img: Failed to load snapshot: Snapshot L1 table too large

 qemu-img: Snapshot L1 table too large

-qemu-img: Error while amending options: File too large

+qemu-img: Failed to turn zero into data clusters: File too large

 Failed to flush the refcount block cache: File too large

 write failed: File too large

 qemu-img: Snapshot L1 table too large

diff --git a/tests/qemu-iotests/112.out b/tests/qemu-iotests/112.out

index 86f0410..ae0318c 100644

--- a/tests/qemu-iotests/112.out

+++ b/tests/qemu-iotests/112.out

@@ -99,13 +99,11 @@ refcount bits: 64

 === Amend to compat=0.10 ===

 qemu-img: compat=0.10 requires refcount_bits=16

-qemu-img: Error while amending options: Operation not supported

 refcount bits: 64

 No errors were found on the image.

 refcount bits: 16

 refcount bits: 16

-qemu-img: Different refcount widths than 16 bits require compatibility level 1.1 or above (use compat=1.1 or greater)

-qemu-img: Error while amending options: Invalid argument

+qemu-img: Refcount widths other than 16 bits require compatibility level 1.1 or above (use compat=1.1 or greater)

 refcount bits: 16

 === Amend with snapshot ===

@@ -113,7 +111,6 @@ refcount bits: 16

 wrote 16777216/16777216 bytes at offset 0

 16 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)

 qemu-img: Cannot decrease refcount entry width to 1 bits: Cluster at offset 0x50000 has a refcount of 2

-qemu-img: Error while amending options: Invalid argument

 No errors were found on the image.

 refcount bits: 16

 No errors were found on the image.

-- 

1.8.3.1