[PATCH for-6.0 v3 00/20] block/export: Allow exporting BDSs via FUSE

[PATCH for-6.0 v3 00/20] block/export: Allow exporting BDSs via FUSE

[Max Reitz]

v1: https://lists.nongnu.org/archive/html/qemu-block/2019-12/msg00451.html
v2: https://lists.nongnu.org/archive/html/qemu-block/2020-09/msg01611.html

Branch: https://github.com/XanClic/qemu.git fuse-exports-v3
Branch: https://git.xanclic.moe/XanClic/qemu.git fuse-exports-v3


Hi,

Ever since I found out that you can mount FUSE filesystems on regular
files (not just directories), I had the idea of adding FUSE block
exports to qemu where you can export block nodes as raw images.  The
best thing is that you’d be able to mount an image on itself, so
whatever format it may be in, qemu lets it appear as a raw image (and
you can then use regular tools like dd on it).

The performance is quite bad so far, but we can always try to improve it
if the need arises.  For now I consider it mostly a cute feature to get
easy access to the raw contents of image files in any format (without
requiring root rights).


This series does the following:

First, add the FUSE export module (block/export/fuse.c) that implements
the basic file access functions.  (Note that you need libfuse 3.8.0 or
later for SEEK_HOLE/SEEK_DATA.)

Second, it allows using FUSE exports as a protocol in the iotests and
makes many iotests work with it.  (The file node is exported by a
background qemu instance to $SOCK_DIR.)

This gives us a lot of coverage for, well, not free (it does take twelve
patches), but for cheap; but there are still some more specialized
things we want to test, so third and last, this series adds an iotest
dedicated to FUSE exports.


Changes from v2:
- Let meson handle the libfuse and feature (lseek) detection
- Rebase on top of vhost-user-blk export
- Patch 2:
  - %s/5\.2/6.0/
  - Renamed init_fuse() to init_exports_table(), so I can add a
    fuse_init() without being too confusing
  - Set max read/write request sizes (using that fuse_init() function,
    and mount options that libfuse still needs for max_read)
  - Run fuse_session_receive_buf() in a loop until something other than
    EINTR is returned
  - Let setup_fuse_export() clean up
  - Unmount and destroy the FUSE session only in fuse_export_delete()
    (after all I/O has settled and thus all references have been
    dropped)
  - Add MAINTAINERS entry
- Patch 3:
  - Don't use bdrv_query_image_info() when all we want is
    bdrv_get_allocated_file_size()
  - Optionally let fuse_do_truncate() require zeroes in the added areas
    (there is one fallocate() case where we don't need zeroes there)
  - Error out if the max read/write request sizes have been exceeded
    instead of (wrongly) limiting the request size
  - Rename fuse_flush() to fuse_fsync(), and let a new fuse_flush()
    invoke fuse_fsync()
- Patch 4:
  - Keep RESIZE permission for growable exports
- Patch 5:
  - Fix two bugs where I forgot to increment the offset when iterating
    over some area
- Patch 17:
  - %s/QEMU_STGD/QSD/
- Patch 18:
  - %s/QEMU_STGD/QSD/
  - Drop superfluous -T from df invocation


git-backport-diff against v3:

Key:
[----] : patches are identical
[####] : number of functional differences between upstream/downstream patch
[down] : patch is downstream-only
The flags [FC] indicate (F)unctional and (C)ontextual differences, respectively

001/20:[down] 'meson: Detect libfuse'
002/20:[0103] [FC] 'fuse: Allow exporting BDSs via FUSE'
003/20:[0058] [FC] 'fuse: Implement standard FUSE operations'
004/20:[0034] [FC] 'fuse: Allow growable exports'
005/20:[0011] [FC] 'fuse: (Partially) implement fallocate()'
006/20:[0063] [FC] 'fuse: Implement hole detection through lseek'
007/20:[----] [--] 'iotests: Do not needlessly filter _make_test_img'
008/20:[----] [--] 'iotests: Do not pipe _make_test_img'
009/20:[----] [--] 'iotests: Use convert -n in some cases'
010/20:[----] [--] 'iotests/046: Avoid renaming images'
011/20:[----] [--] 'iotests: Derive image names from $TEST_IMG'
012/20:[----] [--] 'iotests/091: Use _cleanup_qemu instad of "wait"'
013/20:[----] [--] 'iotests: Restrict some Python tests to file'
014/20:[----] [--] 'iotests: Let _make_test_img guess $TEST_IMG_FILE'
015/20:[----] [--] 'iotests/287: Clean up subshell test image'
016/20:[----] [--] 'storage-daemon: Call bdrv_close_all() on exit'
017/20:[0018] [FC] 'iotests: Give access to the qemu-storage-daemon'
018/20:[0004] [FC] 'iotests: Allow testing FUSE exports'
019/20:[----] [--] 'iotests: Enable fuse for many tests'
020/20:[----] [--] 'iotests/308: Add test for FUSE exports'


Max Reitz (20):
  meson: Detect libfuse
  fuse: Allow exporting BDSs via FUSE
  fuse: Implement standard FUSE operations
  fuse: Allow growable exports
  fuse: (Partially) implement fallocate()
  fuse: Implement hole detection through lseek
  iotests: Do not needlessly filter _make_test_img
  iotests: Do not pipe _make_test_img
  iotests: Use convert -n in some cases
  iotests/046: Avoid renaming images
  iotests: Derive image names from $TEST_IMG
  iotests/091: Use _cleanup_qemu instad of "wait"
  iotests: Restrict some Python tests to file
  iotests: Let _make_test_img guess $TEST_IMG_FILE
  iotests/287: Clean up subshell test image
  storage-daemon: Call bdrv_close_all() on exit
  iotests: Give access to the qemu-storage-daemon
  iotests: Allow testing FUSE exports
  iotests: Enable fuse for many tests
  iotests/308: Add test for FUSE exports

 configure                            |  13 +
 meson.build                          |  26 +
 qapi/block-export.json               |  27 +-
 include/block/fuse.h                 |  30 ++
 block.c                              |   1 +
 block/export/export.c                |   4 +
 block/export/fuse.c                  | 726 +++++++++++++++++++++++++++
 storage-daemon/qemu-storage-daemon.c |   3 +
 MAINTAINERS                          |   6 +
 block/export/meson.build             |   1 +
 meson_options.txt                    |   4 +
 tests/qemu-iotests/025               |   2 +-
 tests/qemu-iotests/026               |   2 +-
 tests/qemu-iotests/028               |  16 +-
 tests/qemu-iotests/028.out           |   3 +
 tests/qemu-iotests/031               |   2 +-
 tests/qemu-iotests/034               |   2 +-
 tests/qemu-iotests/036               |   2 +-
 tests/qemu-iotests/037               |   2 +-
 tests/qemu-iotests/038               |   2 +-
 tests/qemu-iotests/039               |   2 +-
 tests/qemu-iotests/046               |   7 +-
 tests/qemu-iotests/046.out           |   2 +-
 tests/qemu-iotests/050               |   2 +-
 tests/qemu-iotests/054               |   2 +-
 tests/qemu-iotests/060               |   2 +-
 tests/qemu-iotests/071               |  21 +-
 tests/qemu-iotests/079               |   2 +-
 tests/qemu-iotests/080               |   2 +-
 tests/qemu-iotests/089               |   5 +-
 tests/qemu-iotests/089.out           |   1 +
 tests/qemu-iotests/090               |   2 +-
 tests/qemu-iotests/091               |   5 +-
 tests/qemu-iotests/095               |   2 +-
 tests/qemu-iotests/097               |   2 +-
 tests/qemu-iotests/098               |   2 +-
 tests/qemu-iotests/102               |   2 +-
 tests/qemu-iotests/103               |   2 +-
 tests/qemu-iotests/106               |   2 +-
 tests/qemu-iotests/107               |   2 +-
 tests/qemu-iotests/108               |   2 +-
 tests/qemu-iotests/111               |   2 +-
 tests/qemu-iotests/112               |   2 +-
 tests/qemu-iotests/115               |   2 +-
 tests/qemu-iotests/117               |   2 +-
 tests/qemu-iotests/120               |   2 +-
 tests/qemu-iotests/121               |   2 +-
 tests/qemu-iotests/127               |   2 +-
 tests/qemu-iotests/133               |   2 +-
 tests/qemu-iotests/137               |   2 +-
 tests/qemu-iotests/138               |   2 +-
 tests/qemu-iotests/140               |   2 +-
 tests/qemu-iotests/154               |   2 +-
 tests/qemu-iotests/161               |  14 +-
 tests/qemu-iotests/171               |   2 +-
 tests/qemu-iotests/174               |  10 +-
 tests/qemu-iotests/175               |   8 +-
 tests/qemu-iotests/176               |   2 +-
 tests/qemu-iotests/177               |   2 +-
 tests/qemu-iotests/179               |   2 +-
 tests/qemu-iotests/183               |   2 +-
 tests/qemu-iotests/186               |   2 +-
 tests/qemu-iotests/187               |   2 +-
 tests/qemu-iotests/191               |   2 +-
 tests/qemu-iotests/195               |   2 +-
 tests/qemu-iotests/200               |   5 +-
 tests/qemu-iotests/200.out           |   4 +-
 tests/qemu-iotests/204               |   2 +-
 tests/qemu-iotests/206               |   3 +-
 tests/qemu-iotests/214               |   2 +-
 tests/qemu-iotests/217               |   2 +-
 tests/qemu-iotests/220               |   2 +-
 tests/qemu-iotests/221               |   2 +-
 tests/qemu-iotests/229               |   5 +-
 tests/qemu-iotests/229.out           |   6 +-
 tests/qemu-iotests/242               |   3 +-
 tests/qemu-iotests/247               |   2 +-
 tests/qemu-iotests/249               |   8 +-
 tests/qemu-iotests/250               |   2 +-
 tests/qemu-iotests/252               |   2 +-
 tests/qemu-iotests/265               |   2 +-
 tests/qemu-iotests/268               |   2 +-
 tests/qemu-iotests/272               |   2 +-
 tests/qemu-iotests/273               |   2 +-
 tests/qemu-iotests/279               |   2 +-
 tests/qemu-iotests/286               |   2 +-
 tests/qemu-iotests/287               |   6 +-
 tests/qemu-iotests/289               |   2 +-
 tests/qemu-iotests/290               |   2 +-
 tests/qemu-iotests/291               |   2 +-
 tests/qemu-iotests/292               |   2 +-
 tests/qemu-iotests/293               |   2 +-
 tests/qemu-iotests/294               |   2 +-
 tests/qemu-iotests/305               |   2 +-
 tests/qemu-iotests/308               | 339 +++++++++++++
 tests/qemu-iotests/308.out           |  97 ++++
 tests/qemu-iotests/check             |  17 +
 tests/qemu-iotests/common.filter     |   5 +-
 tests/qemu-iotests/common.rc         | 181 ++++++-
 tests/qemu-iotests/group             |   1 +
 100 files changed, 1615 insertions(+), 126 deletions(-)
 create mode 100644 include/block/fuse.h
 create mode 100644 block/export/fuse.c
 create mode 100755 tests/qemu-iotests/308
 create mode 100644 tests/qemu-iotests/308.out

-- 
2.26.2

[PATCH for-6.0 v3 01/20] meson: Detect libfuse

[Max Reitz]

Signed-off-by: Max Reitz <mreitz@redhat.com>
---
 configure         | 7 +++++++
 meson.build       | 6 ++++++
 meson_options.txt | 2 ++
 3 files changed, 15 insertions(+)

diff --git a/configure b/configure
index 83610b0db8..fc315deebe 100755
--- a/configure
+++ b/configure
@@ -448,6 +448,7 @@ meson=""
 ninja=""
 skip_meson=no
 gettext=""
+fuse="auto"
 
 bogus_os="no"
 malloc_trim="auto"
@@ -1519,6 +1520,10 @@ for opt do
   ;;
   --disable-libdaxctl) libdaxctl=no
   ;;
+  --enable-fuse) fuse="enabled"
+  ;;
+  --disable-fuse) fuse="disabled"
+  ;;
   *)
       echo "ERROR: unknown option $opt"
       echo "Try '$0 --help' for more information"
@@ -1841,6 +1846,7 @@ disabled with --disable-FEATURE, default is enabled if available:
   xkbcommon       xkbcommon support
   rng-none        dummy RNG, avoid using /dev/(u)random and getrandom()
   libdaxctl       libdaxctl support
+  fuse            FUSE block device export
 
 NOTE: The object files are built at the place where configure is launched
 EOF
@@ -6982,6 +6988,7 @@ NINJA=$ninja $meson setup \
         -Dcapstone=$capstone -Dslirp=$slirp -Dfdt=$fdt \
         -Diconv=$iconv -Dcurses=$curses -Dlibudev=$libudev\
         -Ddocs=$docs -Dsphinx_build=$sphinx_build -Dinstall_blobs=$blobs \
+        -Dfuse=$fuse \
         $cross_arg \
         "$PWD" "$source_path"
 
diff --git a/meson.build b/meson.build
index 47e32e1fcb..4e8436b456 100644
--- a/meson.build
+++ b/meson.build
@@ -736,6 +736,10 @@ if not has_malloc_trim and get_option('malloc_trim').enabled()
   endif
 endif
 
+fuse = dependency('fuse3', required: get_option('fuse'),
+                  version: '>=3.1', method: 'pkg-config',
+                  static: enable_static)
+
 #################
 # config-host.h #
 #################
@@ -768,6 +772,7 @@ config_host_data.set('CONFIG_XKBCOMMON', xkbcommon.found())
 config_host_data.set('CONFIG_KEYUTILS', keyutils.found())
 config_host_data.set('CONFIG_GETTID', has_gettid)
 config_host_data.set('CONFIG_MALLOC_TRIM', has_malloc_trim)
+config_host_data.set('CONFIG_FUSE', fuse.found())
 config_host_data.set('QEMU_VERSION', '"@0@"'.format(meson.project_version()))
 config_host_data.set('QEMU_VERSION_MAJOR', meson.project_version().split('.')[0])
 config_host_data.set('QEMU_VERSION_MINOR', meson.project_version().split('.')[1])
@@ -2163,6 +2168,7 @@ endif
 summary_info += {'thread sanitizer':  config_host.has_key('CONFIG_TSAN')}
 summary_info += {'rng-none':          config_host.has_key('CONFIG_RNG_NONE')}
 summary_info += {'Linux keyring':     config_host.has_key('CONFIG_SECRET_KEYRING')}
+summary_info += {'FUSE exports':      fuse.found()}
 summary(summary_info, bool_yn: true)
 
 if not supported_cpus.contains(cpu)
diff --git a/meson_options.txt b/meson_options.txt
index b4f1801875..2ef4ec628f 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -64,6 +64,8 @@ option('xkbcommon', type : 'feature', value : 'auto',
        description: 'xkbcommon support')
 option('virtiofsd', type: 'feature', value: 'auto',
        description: 'build virtiofs daemon (virtiofsd)')
+option('fuse', type: 'feature', value: 'auto',
+       description: 'FUSE block device export')
 
 option('capstone', type: 'combo', value: 'auto',
        choices: ['disabled', 'enabled', 'auto', 'system', 'internal'],
-- 
2.26.2

[PATCH for-6.0 v3 02/20] fuse: Allow exporting BDSs via FUSE

[Max Reitz]

block-export-add type=fuse allows mounting block graph nodes via FUSE on
some existing regular file.  That file should then appears like a raw
disk image, and accesses to it result in accesses to the exported BDS.

Right now, we only implement the necessary block export functions to set
it up and shut it down.  We do not implement any access functions, so
accessing the mount point only results in errors.  This will be
addressed by a followup patch.

We keep a hash table of exported mount points, because we want to be
able to detect when users try to use a mount point twice.  This is
because we invoke stat() to check whether the given mount point is a
regular file, but if that file is served by ourselves (because it is
already used as a mount point), then this stat() would have to be served
by ourselves, too, which is impossible to do while we (as the caller)
are waiting for it to settle.  Therefore, keep track of mount point
paths to at least catch the most obvious instances of that problem.

Signed-off-by: Max Reitz <mreitz@redhat.com>
---
 qapi/block-export.json   |  23 ++-
 include/block/fuse.h     |  30 ++++
 block.c                  |   1 +
 block/export/export.c    |   4 +
 block/export/fuse.c      | 295 +++++++++++++++++++++++++++++++++++++++
 MAINTAINERS              |   6 +
 block/export/meson.build |   1 +
 7 files changed, 358 insertions(+), 2 deletions(-)
 create mode 100644 include/block/fuse.h
 create mode 100644 block/export/fuse.c

diff --git a/qapi/block-export.json b/qapi/block-export.json
index 480c497690..aecf052c07 100644
--- a/qapi/block-export.json
+++ b/qapi/block-export.json
@@ -103,6 +103,21 @@
 	    '*logical-block-size': 'size',
             '*num-queues': 'uint16'} }
 
+##
+# @BlockExportOptionsFuse:
+#
+# Options for exporting a block graph node on some (file) mountpoint
+# as a raw image.
+#
+# @mountpoint: Path on which to export the block device via FUSE.
+#              This must point to an existing regular file.
+#
+# Since: 6.0
+##
+{ 'struct': 'BlockExportOptionsFuse',
+  'data': { 'mountpoint': 'str' },
+  'if': 'defined(CONFIG_FUSE)' }
+
 ##
 # @NbdServerAddOptions:
 #
@@ -200,11 +215,13 @@
 #
 # @nbd: NBD export
 # @vhost-user-blk: vhost-user-blk export (since 5.2)
+# @fuse: FUSE export (since: 6.0)
 #
 # Since: 4.2
 ##
 { 'enum': 'BlockExportType',
-  'data': [ 'nbd', 'vhost-user-blk' ] }
+  'data': [ 'nbd', 'vhost-user-blk',
+            { 'name': 'fuse', 'if': 'defined(CONFIG_FUSE)' } ] }
 
 ##
 # @BlockExportOptions:
@@ -245,7 +262,9 @@
   'discriminator': 'type',
   'data': {
       'nbd': 'BlockExportOptionsNbd',
-      'vhost-user-blk': 'BlockExportOptionsVhostUserBlk'
+      'vhost-user-blk': 'BlockExportOptionsVhostUserBlk',
+      'fuse': { 'type': 'BlockExportOptionsFuse',
+                'if': 'defined(CONFIG_FUSE)' }
    } }
 
 ##
diff --git a/include/block/fuse.h b/include/block/fuse.h
new file mode 100644
index 0000000000..ffa91fe364
--- /dev/null
+++ b/include/block/fuse.h
@@ -0,0 +1,30 @@
+/*
+ * Present a block device as a raw image through FUSE
+ *
+ * Copyright (c) 2020 Max Reitz <mreitz@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; under version 2 or later of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef BLOCK_FUSE_H
+#define BLOCK_FUSE_H
+
+#ifdef CONFIG_FUSE
+
+#include "block/export.h"
+
+extern const BlockExportDriver blk_exp_fuse;
+
+#endif /* CONFIG_FUSE */
+
+#endif
diff --git a/block.c b/block.c
index ee5b28a979..82b0f1887a 100644
--- a/block.c
+++ b/block.c
@@ -26,6 +26,7 @@
 #include "block/trace.h"
 #include "block/block_int.h"
 #include "block/blockjob.h"
+#include "block/fuse.h"
 #include "block/nbd.h"
 #include "block/qdict.h"
 #include "qemu/error-report.h"
diff --git a/block/export/export.c b/block/export/export.c
index c3478c6c97..778adc428e 100644
--- a/block/export/export.c
+++ b/block/export/export.c
@@ -17,6 +17,7 @@
 #include "sysemu/block-backend.h"
 #include "sysemu/iothread.h"
 #include "block/export.h"
+#include "block/fuse.h"
 #include "block/nbd.h"
 #include "qapi/error.h"
 #include "qapi/qapi-commands-block-export.h"
@@ -31,6 +32,9 @@ static const BlockExportDriver *blk_exp_drivers[] = {
 #if defined(CONFIG_LINUX) && defined(CONFIG_VHOST_USER)
     &blk_exp_vhost_user_blk,
 #endif
+#ifdef CONFIG_FUSE
+    &blk_exp_fuse,
+#endif
 };
 
 /* Only accessed from the main thread */
diff --git a/block/export/fuse.c b/block/export/fuse.c
new file mode 100644
index 0000000000..0553bcd630
--- /dev/null
+++ b/block/export/fuse.c
@@ -0,0 +1,295 @@
+/*
+ * Present a block device as a raw image through FUSE
+ *
+ * Copyright (c) 2020 Max Reitz <mreitz@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; under version 2 or later of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define FUSE_USE_VERSION 31
+
+#include "qemu/osdep.h"
+#include "block/aio.h"
+#include "block/block.h"
+#include "block/export.h"
+#include "block/fuse.h"
+#include "block/qapi.h"
+#include "qapi/error.h"
+#include "qapi/qapi-commands-block.h"
+#include "sysemu/block-backend.h"
+
+#include <fuse.h>
+#include <fuse_lowlevel.h>
+
+
+/* Prevent overly long bounce buffer allocations */
+#define FUSE_MAX_BOUNCE_BYTES (MIN(BDRV_REQUEST_MAX_BYTES, 64 * 1024 * 1024))
+
+
+typedef struct FuseExport {
+    BlockExport common;
+
+    struct fuse_session *fuse_session;
+    struct fuse_buf fuse_buf;
+    bool mounted, fd_handler_set_up;
+
+    char *mountpoint;
+    bool writable;
+} FuseExport;
+
+static GHashTable *exports;
+static const struct fuse_lowlevel_ops fuse_ops;
+
+static void fuse_export_shutdown(BlockExport *exp);
+static void fuse_export_delete(BlockExport *exp);
+
+static void init_exports_table(void);
+
+static int setup_fuse_export(FuseExport *exp, const char *mountpoint,
+                             Error **errp);
+static void read_from_fuse_export(void *opaque);
+
+static bool is_regular_file(const char *path, Error **errp);
+
+
+static int fuse_export_create(BlockExport *blk_exp,
+                              BlockExportOptions *blk_exp_args,
+                              Error **errp)
+{
+    FuseExport *exp = container_of(blk_exp, FuseExport, common);
+    BlockExportOptionsFuse *args = &blk_exp_args->u.fuse;
+    int ret;
+
+    assert(blk_exp_args->type == BLOCK_EXPORT_TYPE_FUSE);
+
+    init_exports_table();
+
+    /*
+     * It is important to do this check before calling is_regular_file() --
+     * that function will do a stat(), which we would have to handle if we
+     * already exported something on @mountpoint.  But we cannot, because
+     * we are currently caught up here.
+     * (Note that ideally we would want to resolve relative paths here,
+     * but bdrv_make_absolute_filename() might do the wrong thing for
+     * paths that contain colons, and realpath() would resolve symlinks,
+     * which we do not want: The mount point is not going to be the
+     * symlink's destination, but the link itself.)
+     * So this will not catch all potential clashes, but hopefully at
+     * least the most common one of specifying exactly the same path
+     * string twice.
+     */
+    if (g_hash_table_contains(exports, args->mountpoint)) {
+        error_setg(errp, "There already is a FUSE export on '%s'",
+                   args->mountpoint);
+        ret = -EEXIST;
+        goto fail;
+    }
+
+    if (!is_regular_file(args->mountpoint, errp)) {
+        ret = -EINVAL;
+        goto fail;
+    }
+
+    exp->mountpoint = g_strdup(args->mountpoint);
+    exp->writable = blk_exp_args->writable;
+
+    ret = setup_fuse_export(exp, args->mountpoint, errp);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    return 0;
+
+fail:
+    fuse_export_delete(blk_exp);
+    return ret;
+}
+
+/**
+ * Allocates the global @exports hash table.
+ */
+static void init_exports_table(void)
+{
+    if (exports) {
+        return;
+    }
+
+    exports = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, NULL);
+}
+
+/**
+ * Create exp->fuse_session and mount it.
+ */
+static int setup_fuse_export(FuseExport *exp, const char *mountpoint,
+                             Error **errp)
+{
+    const char *fuse_argv[4];
+    char *mount_opts;
+    struct fuse_args fuse_args;
+    int ret;
+
+    /* Needs to match what fuse_init() sets.  Only max_read must be supplied. */
+    mount_opts = g_strdup_printf("max_read=%zu", FUSE_MAX_BOUNCE_BYTES);
+
+    fuse_argv[0] = ""; /* Dummy program name */
+    fuse_argv[1] = "-o";
+    fuse_argv[2] = mount_opts;
+    fuse_argv[3] = NULL;
+    fuse_args = (struct fuse_args)FUSE_ARGS_INIT(3, (char **)fuse_argv);
+
+    exp->fuse_session = fuse_session_new(&fuse_args, &fuse_ops,
+                                         sizeof(fuse_ops), exp);
+    g_free(mount_opts);
+    if (!exp->fuse_session) {
+        error_setg(errp, "Failed to set up FUSE session");
+        ret = -EIO;
+        goto fail;
+    }
+
+    ret = fuse_session_mount(exp->fuse_session, mountpoint);
+    if (ret < 0) {
+        error_setg(errp, "Failed to mount FUSE session to export");
+        ret = -EIO;
+        goto fail;
+    }
+    exp->mounted = true;
+
+    g_hash_table_insert(exports, g_strdup(mountpoint), NULL);
+
+    aio_set_fd_handler(exp->common.ctx,
+                       fuse_session_fd(exp->fuse_session), true,
+                       read_from_fuse_export, NULL, NULL, exp);
+    exp->fd_handler_set_up = true;
+
+    return 0;
+
+fail:
+    fuse_export_shutdown(&exp->common);
+    return ret;
+}
+
+/**
+ * Callback to be invoked when the FUSE session FD can be read from.
+ * (This is basically the FUSE event loop.)
+ */
+static void read_from_fuse_export(void *opaque)
+{
+    FuseExport *exp = opaque;
+    int ret;
+
+    blk_exp_ref(&exp->common);
+
+    do {
+        ret = fuse_session_receive_buf(exp->fuse_session, &exp->fuse_buf);
+    } while (ret == -EINTR);
+    if (ret < 0) {
+        goto out;
+    }
+
+    fuse_session_process_buf(exp->fuse_session, &exp->fuse_buf);
+
+out:
+    blk_exp_unref(&exp->common);
+}
+
+static void fuse_export_shutdown(BlockExport *blk_exp)
+{
+    FuseExport *exp = container_of(blk_exp, FuseExport, common);
+
+    if (exp->fuse_session) {
+        fuse_session_exit(exp->fuse_session);
+
+        if (exp->fd_handler_set_up) {
+            aio_set_fd_handler(exp->common.ctx,
+                               fuse_session_fd(exp->fuse_session), true,
+                               NULL, NULL, NULL, NULL);
+            exp->fd_handler_set_up = false;
+        }
+    }
+
+    if (exp->mountpoint) {
+        /*
+         * Safe to drop now, because we will not handle any requests
+         * for this export anymore anyway.
+         */
+        g_hash_table_remove(exports, exp->mountpoint);
+    }
+}
+
+static void fuse_export_delete(BlockExport *blk_exp)
+{
+    FuseExport *exp = container_of(blk_exp, FuseExport, common);
+
+    if (exp->fuse_session) {
+        if (exp->mounted) {
+            fuse_session_unmount(exp->fuse_session);
+        }
+
+        fuse_session_destroy(exp->fuse_session);
+    }
+
+    free(exp->fuse_buf.mem);
+    g_free(exp->mountpoint);
+}
+
+/**
+ * Check whether @path points to a regular file.  If not, put an
+ * appropriate message into *errp.
+ */
+static bool is_regular_file(const char *path, Error **errp)
+{
+    struct stat statbuf;
+    int ret;
+
+    ret = stat(path, &statbuf);
+    if (ret < 0) {
+        error_setg_errno(errp, errno, "Failed to stat '%s'", path);
+        return false;
+    }
+
+    if (!S_ISREG(statbuf.st_mode)) {
+        error_setg(errp, "'%s' is not a regular file", path);
+        return false;
+    }
+
+    return true;
+}
+
+/**
+ * A chance to set change some parameters supplied to FUSE_INIT.
+ */
+static void fuse_init(void *userdata, struct fuse_conn_info *conn)
+{
+    /*
+     * MIN_NON_ZERO() would not be wrong here, but what we set here
+     * must equal what has been passed to fuse_session_new().
+     * Therefore, as long as max_read must be passed as a mount option
+     * (which libfuse claims will be changed at some point), we have
+     * to set max_read to a fixed value here.
+     */
+    conn->max_read = FUSE_MAX_BOUNCE_BYTES;
+
+    conn->max_write = MIN_NON_ZERO(BDRV_REQUEST_MAX_BYTES, conn->max_write);
+}
+
+static const struct fuse_lowlevel_ops fuse_ops = {
+    .init       = fuse_init,
+};
+
+const BlockExportDriver blk_exp_fuse = {
+    .type               = BLOCK_EXPORT_TYPE_FUSE,
+    .instance_size      = sizeof(FuseExport),
+    .create             = fuse_export_create,
+    .delete             = fuse_export_delete,
+    .request_shutdown   = fuse_export_shutdown,
+};
diff --git a/MAINTAINERS b/MAINTAINERS
index ef6f5c7399..588dd9e055 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3078,6 +3078,12 @@ F: include/qemu/vhost-user-server.h
 F: tests/qtest/libqos/vhost-user-blk.c
 F: util/vhost-user-server.c
 
+FUSE block device exports
+M: Max Reitz <mreitz@redhat.com>
+L: qemu-block@nongnu.org
+S: Supported
+F: block/export/fuse.c
+
 Replication
 M: Wen Congyang <wencongyang2@huawei.com>
 M: Xie Changlong <xiechanglong.d@gmail.com>
diff --git a/block/export/meson.build b/block/export/meson.build
index 9fb4fbf81d..bf442fc670 100644
--- a/block/export/meson.build
+++ b/block/export/meson.build
@@ -1,2 +1,3 @@
 blockdev_ss.add(files('export.c'))
 blockdev_ss.add(when: ['CONFIG_LINUX', 'CONFIG_VHOST_USER'], if_true: files('vhost-user-blk-server.c'))
+blockdev_ss.add(when: fuse, if_true: files('fuse.c'))
-- 
2.26.2

[PATCH for-6.0 v3 03/20] fuse: Implement standard FUSE operations

[Max Reitz]

This makes the export actually useful instead of only producing errors
whenever it is accessed.

Signed-off-by: Max Reitz <mreitz@redhat.com>
---
 block/export/fuse.c | 242 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 242 insertions(+)

diff --git a/block/export/fuse.c b/block/export/fuse.c
index 0553bcd630..d995829ab7 100644
--- a/block/export/fuse.c
+++ b/block/export/fuse.c
@@ -282,8 +282,250 @@ static void fuse_init(void *userdata, struct fuse_conn_info *conn)
     conn->max_write = MIN_NON_ZERO(BDRV_REQUEST_MAX_BYTES, conn->max_write);
 }
 
+/**
+ * Let clients look up files.  Always return ENOENT because we only
+ * care about the mountpoint itself.
+ */
+static void fuse_lookup(fuse_req_t req, fuse_ino_t parent, const char *name)
+{
+    fuse_reply_err(req, ENOENT);
+}
+
+/**
+ * Let clients get file attributes (i.e., stat() the file).
+ */
+static void fuse_getattr(fuse_req_t req, fuse_ino_t inode,
+                         struct fuse_file_info *fi)
+{
+    struct stat statbuf;
+    int64_t length, allocated_blocks;
+    time_t now = time(NULL);
+    FuseExport *exp = fuse_req_userdata(req);
+    mode_t mode;
+
+    length = blk_getlength(exp->common.blk);
+    if (length < 0) {
+        fuse_reply_err(req, -length);
+        return;
+    }
+
+    allocated_blocks = bdrv_get_allocated_file_size(blk_bs(exp->common.blk));
+    if (allocated_blocks <= 0) {
+        allocated_blocks = DIV_ROUND_UP(length, 512);
+    } else {
+        allocated_blocks = DIV_ROUND_UP(allocated_blocks, 512);
+    }
+
+    mode = S_IFREG | S_IRUSR;
+    if (exp->writable) {
+        mode |= S_IWUSR;
+    }
+
+    statbuf = (struct stat) {
+        .st_ino     = inode,
+        .st_mode    = mode,
+        .st_nlink   = 1,
+        .st_uid     = getuid(),
+        .st_gid     = getgid(),
+        .st_size    = length,
+        .st_blksize = blk_bs(exp->common.blk)->bl.request_alignment,
+        .st_blocks  = allocated_blocks,
+        .st_atime   = now,
+        .st_mtime   = now,
+        .st_ctime   = now,
+    };
+
+    fuse_reply_attr(req, &statbuf, 1.);
+}
+
+static int fuse_do_truncate(const FuseExport *exp, int64_t size,
+                            bool req_zero_write, PreallocMode prealloc)
+{
+    uint64_t blk_perm, blk_shared_perm;
+    BdrvRequestFlags truncate_flags = 0;
+    int ret;
+
+    if (req_zero_write) {
+        truncate_flags |= BDRV_REQ_ZERO_WRITE;
+    }
+
+    blk_get_perm(exp->common.blk, &blk_perm, &blk_shared_perm);
+
+    ret = blk_set_perm(exp->common.blk, blk_perm | BLK_PERM_RESIZE,
+                       blk_shared_perm, NULL);
+    if (ret < 0) {
+        return ret;
+    }
+
+    ret = blk_truncate(exp->common.blk, size, true, prealloc,
+                       truncate_flags, NULL);
+
+    /* Must succeed, because we are only giving up the RESIZE permission */
+    blk_set_perm(exp->common.blk, blk_perm, blk_shared_perm, &error_abort);
+
+    return ret;
+}
+
+/**
+ * Let clients set file attributes.  Only resizing is supported.
+ */
+static void fuse_setattr(fuse_req_t req, fuse_ino_t inode, struct stat *statbuf,
+                         int to_set, struct fuse_file_info *fi)
+{
+    FuseExport *exp = fuse_req_userdata(req);
+    int ret;
+
+    if (!exp->writable) {
+        fuse_reply_err(req, EACCES);
+        return;
+    }
+
+    if (to_set & ~FUSE_SET_ATTR_SIZE) {
+        fuse_reply_err(req, ENOTSUP);
+        return;
+    }
+
+    ret = fuse_do_truncate(exp, statbuf->st_size, true, PREALLOC_MODE_OFF);
+    if (ret < 0) {
+        fuse_reply_err(req, -ret);
+        return;
+    }
+
+    fuse_getattr(req, inode, fi);
+}
+
+/**
+ * Let clients open a file (i.e., the exported image).
+ */
+static void fuse_open(fuse_req_t req, fuse_ino_t inode,
+                      struct fuse_file_info *fi)
+{
+    fuse_reply_open(req, fi);
+}
+
+/**
+ * Handle client reads from the exported image.
+ */
+static void fuse_read(fuse_req_t req, fuse_ino_t inode,
+                      size_t size, off_t offset, struct fuse_file_info *fi)
+{
+    FuseExport *exp = fuse_req_userdata(req);
+    int64_t length;
+    void *buf;
+    int ret;
+
+    /* Limited by max_read, should not happen */
+    if (size > FUSE_MAX_BOUNCE_BYTES) {
+        fuse_reply_err(req, EINVAL);
+        return;
+    }
+
+    /**
+     * Clients will expect short reads at EOF, so we have to limit
+     * offset+size to the image length.
+     */
+    length = blk_getlength(exp->common.blk);
+    if (length < 0) {
+        fuse_reply_err(req, -length);
+        return;
+    }
+
+    if (offset + size > length) {
+        size = length - offset;
+    }
+
+    buf = qemu_try_blockalign(blk_bs(exp->common.blk), size);
+    if (!buf) {
+        fuse_reply_err(req, ENOMEM);
+        return;
+    }
+
+    ret = blk_pread(exp->common.blk, offset, buf, size);
+    if (ret >= 0) {
+        fuse_reply_buf(req, buf, size);
+    } else {
+        fuse_reply_err(req, -ret);
+    }
+
+    qemu_vfree(buf);
+}
+
+/**
+ * Handle client writes to the exported image.
+ */
+static void fuse_write(fuse_req_t req, fuse_ino_t inode, const char *buf,
+                       size_t size, off_t offset, struct fuse_file_info *fi)
+{
+    FuseExport *exp = fuse_req_userdata(req);
+    int64_t length;
+    int ret;
+
+    /* Limited by max_write, should not happen */
+    if (size > BDRV_REQUEST_MAX_BYTES) {
+        fuse_reply_err(req, EINVAL);
+        return;
+    }
+
+    if (!exp->writable) {
+        fuse_reply_err(req, EACCES);
+        return;
+    }
+
+    /**
+     * Clients will expect short writes at EOF, so we have to limit
+     * offset+size to the image length.
+     */
+    length = blk_getlength(exp->common.blk);
+    if (length < 0) {
+        fuse_reply_err(req, -length);
+        return;
+    }
+
+    if (offset + size > length) {
+        size = length - offset;
+    }
+
+    ret = blk_pwrite(exp->common.blk, offset, buf, size, 0);
+    if (ret >= 0) {
+        fuse_reply_write(req, size);
+    } else {
+        fuse_reply_err(req, -ret);
+    }
+}
+
+/**
+ * Let clients fsync the exported image.
+ */
+static void fuse_fsync(fuse_req_t req, fuse_ino_t inode, int datasync,
+                       struct fuse_file_info *fi)
+{
+    FuseExport *exp = fuse_req_userdata(req);
+    int ret;
+
+    ret = blk_flush(exp->common.blk);
+    fuse_reply_err(req, ret < 0 ? -ret : 0);
+}
+
+/**
+ * Called before an FD to the exported image is closed.  (libfuse
+ * notes this to be a way to return last-minute errors.)
+ */
+static void fuse_flush(fuse_req_t req, fuse_ino_t inode,
+                        struct fuse_file_info *fi)
+{
+    fuse_fsync(req, inode, 1, fi);
+}
+
 static const struct fuse_lowlevel_ops fuse_ops = {
     .init       = fuse_init,
+    .lookup     = fuse_lookup,
+    .getattr    = fuse_getattr,
+    .setattr    = fuse_setattr,
+    .open       = fuse_open,
+    .read       = fuse_read,
+    .write      = fuse_write,
+    .flush      = fuse_flush,
+    .fsync      = fuse_fsync,
 };
 
 const BlockExportDriver blk_exp_fuse = {
-- 
2.26.2

[PATCH for-6.0 v3 04/20] fuse: Allow growable exports

[Max Reitz]

These will behave more like normal files in that writes beyond the EOF
will automatically grow the export size.

As an optimization, keep the RESIZE permission for growable exports so
we do not have to take it for every post-EOF write.  (This permission is
not released when the export is destroyed, because at that point the
BlockBackend is destroyed altogether anyway.)

Signed-off-by: Max Reitz <mreitz@redhat.com>
---
 qapi/block-export.json |  6 +++++-
 block/export/fuse.c    | 44 ++++++++++++++++++++++++++++++++++--------
 2 files changed, 41 insertions(+), 9 deletions(-)

diff --git a/qapi/block-export.json b/qapi/block-export.json
index aecf052c07..140ba0d221 100644
--- a/qapi/block-export.json
+++ b/qapi/block-export.json
@@ -112,10 +112,14 @@
 # @mountpoint: Path on which to export the block device via FUSE.
 #              This must point to an existing regular file.
 #
+# @growable: Whether writes beyond the EOF should grow the block node
+#            accordingly. (default: false)
+#
 # Since: 6.0
 ##
 { 'struct': 'BlockExportOptionsFuse',
-  'data': { 'mountpoint': 'str' },
+  'data': { 'mountpoint': 'str',
+            '*growable': 'bool' },
   'if': 'defined(CONFIG_FUSE)' }
 
 ##
diff --git a/block/export/fuse.c b/block/export/fuse.c
index d995829ab7..92d2f50bcc 100644
--- a/block/export/fuse.c
+++ b/block/export/fuse.c
@@ -45,6 +45,7 @@ typedef struct FuseExport {
 
     char *mountpoint;
     bool writable;
+    bool growable;
 } FuseExport;
 
 static GHashTable *exports;
@@ -72,6 +73,19 @@ static int fuse_export_create(BlockExport *blk_exp,
 
     assert(blk_exp_args->type == BLOCK_EXPORT_TYPE_FUSE);
 
+    /* For growable exports, take the RESIZE permission */
+    if (args->growable) {
+        uint64_t blk_perm, blk_shared_perm;
+
+        blk_get_perm(exp->common.blk, &blk_perm, &blk_shared_perm);
+
+        ret = blk_set_perm(exp->common.blk, blk_perm | BLK_PERM_RESIZE,
+                           blk_shared_perm, errp);
+        if (ret < 0) {
+            return ret;
+        }
+    }
+
     init_exports_table();
 
     /*
@@ -102,6 +116,7 @@ static int fuse_export_create(BlockExport *blk_exp,
 
     exp->mountpoint = g_strdup(args->mountpoint);
     exp->writable = blk_exp_args->writable;
+    exp->growable = args->growable;
 
     ret = setup_fuse_export(exp, args->mountpoint, errp);
     if (ret < 0) {
@@ -349,19 +364,24 @@ static int fuse_do_truncate(const FuseExport *exp, int64_t size,
         truncate_flags |= BDRV_REQ_ZERO_WRITE;
     }
 
-    blk_get_perm(exp->common.blk, &blk_perm, &blk_shared_perm);
+    /* Growable exports have a permanent RESIZE permission */
+    if (!exp->growable) {
+        blk_get_perm(exp->common.blk, &blk_perm, &blk_shared_perm);
 
-    ret = blk_set_perm(exp->common.blk, blk_perm | BLK_PERM_RESIZE,
-                       blk_shared_perm, NULL);
-    if (ret < 0) {
-        return ret;
+        ret = blk_set_perm(exp->common.blk, blk_perm | BLK_PERM_RESIZE,
+                           blk_shared_perm, NULL);
+        if (ret < 0) {
+            return ret;
+        }
     }
 
     ret = blk_truncate(exp->common.blk, size, true, prealloc,
                        truncate_flags, NULL);
 
-    /* Must succeed, because we are only giving up the RESIZE permission */
-    blk_set_perm(exp->common.blk, blk_perm, blk_shared_perm, &error_abort);
+    if (!exp->growable) {
+        /* Must succeed, because we are only giving up the RESIZE permission */
+        blk_set_perm(exp->common.blk, blk_perm, blk_shared_perm, &error_abort);
+    }
 
     return ret;
 }
@@ -482,7 +502,15 @@ static void fuse_write(fuse_req_t req, fuse_ino_t inode, const char *buf,
     }
 
     if (offset + size > length) {
-        size = length - offset;
+        if (exp->growable) {
+            ret = fuse_do_truncate(exp, offset + size, true, PREALLOC_MODE_OFF);
+            if (ret < 0) {
+                fuse_reply_err(req, -ret);
+                return;
+            }
+        } else {
+            size = length - offset;
+        }
     }
 
     ret = blk_pwrite(exp->common.blk, offset, buf, size, 0);
-- 
2.26.2

[PATCH for-6.0 v3 05/20] fuse: (Partially) implement fallocate()

[Max Reitz]

This allows allocating areas after the (old) EOF as part of a growing
resize, writing zeroes, and discarding.

Signed-off-by: Max Reitz <mreitz@redhat.com>
---
 block/export/fuse.c | 84 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 84 insertions(+)

diff --git a/block/export/fuse.c b/block/export/fuse.c
index 92d2f50bcc..0b9d226b2f 100644
--- a/block/export/fuse.c
+++ b/block/export/fuse.c
@@ -521,6 +521,89 @@ static void fuse_write(fuse_req_t req, fuse_ino_t inode, const char *buf,
     }
 }
 
+/**
+ * Let clients perform various fallocate() operations.
+ */
+static void fuse_fallocate(fuse_req_t req, fuse_ino_t inode, int mode,
+                           off_t offset, off_t length,
+                           struct fuse_file_info *fi)
+{
+    FuseExport *exp = fuse_req_userdata(req);
+    int64_t blk_len;
+    int ret;
+
+    if (!exp->writable) {
+        fuse_reply_err(req, EACCES);
+        return;
+    }
+
+    blk_len = blk_getlength(exp->common.blk);
+    if (blk_len < 0) {
+        fuse_reply_err(req, -blk_len);
+        return;
+    }
+
+    if (mode & FALLOC_FL_KEEP_SIZE) {
+        length = MIN(length, blk_len - offset);
+    }
+
+    if (mode & FALLOC_FL_PUNCH_HOLE) {
+        if (!(mode & FALLOC_FL_KEEP_SIZE)) {
+            fuse_reply_err(req, EINVAL);
+            return;
+        }
+
+        do {
+            int size = MIN(length, BDRV_REQUEST_MAX_BYTES);
+
+            ret = blk_pdiscard(exp->common.blk, offset, size);
+            offset += size;
+            length -= size;
+        } while (ret == 0 && length > 0);
+    } else if (mode & FALLOC_FL_ZERO_RANGE) {
+        if (!(mode & FALLOC_FL_KEEP_SIZE) && offset + length > blk_len) {
+            /* No need for zeroes, we are going to write them ourselves */
+            ret = fuse_do_truncate(exp, offset + length, false,
+                                   PREALLOC_MODE_OFF);
+            if (ret < 0) {
+                fuse_reply_err(req, -ret);
+                return;
+            }
+        }
+
+        do {
+            int size = MIN(length, BDRV_REQUEST_MAX_BYTES);
+
+            ret = blk_pwrite_zeroes(exp->common.blk,
+                                    offset, size, 0);
+            offset += size;
+            length -= size;
+        } while (ret == 0 && length > 0);
+    } else if (!mode) {
+        /* We can only fallocate at the EOF with a truncate */
+        if (offset < blk_len) {
+            fuse_reply_err(req, EOPNOTSUPP);
+            return;
+        }
+
+        if (offset > blk_len) {
+            /* No preallocation needed here */
+            ret = fuse_do_truncate(exp, offset, true, PREALLOC_MODE_OFF);
+            if (ret < 0) {
+                fuse_reply_err(req, -ret);
+                return;
+            }
+        }
+
+        ret = fuse_do_truncate(exp, offset + length, true,
+                               PREALLOC_MODE_FALLOC);
+    } else {
+        ret = -EOPNOTSUPP;
+    }
+
+    fuse_reply_err(req, ret < 0 ? -ret : 0);
+}
+
 /**
  * Let clients fsync the exported image.
  */
@@ -552,6 +635,7 @@ static const struct fuse_lowlevel_ops fuse_ops = {
     .open       = fuse_open,
     .read       = fuse_read,
     .write      = fuse_write,
+    .fallocate  = fuse_fallocate,
     .flush      = fuse_flush,
     .fsync      = fuse_fsync,
 };
-- 
2.26.2

[PATCH for-6.0 v3 06/20] fuse: Implement hole detection through lseek

[Max Reitz]

This is a relatively new feature in libfuse (available since 3.8.0,
which was released in November 2019), so we have to add a dedicated
check whether it is available before making use of it.

Signed-off-by: Max Reitz <mreitz@redhat.com>
---
 configure           |  8 ++++-
 meson.build         | 20 ++++++++++++
 block/export/fuse.c | 77 +++++++++++++++++++++++++++++++++++++++++++++
 meson_options.txt   |  2 ++
 4 files changed, 106 insertions(+), 1 deletion(-)

diff --git a/configure b/configure
index fc315deebe..f74b7ef3f4 100755
--- a/configure
+++ b/configure
@@ -449,6 +449,7 @@ ninja=""
 skip_meson=no
 gettext=""
 fuse="auto"
+fuse_lseek="auto"
 
 bogus_os="no"
 malloc_trim="auto"
@@ -1524,6 +1525,10 @@ for opt do
   ;;
   --disable-fuse) fuse="disabled"
   ;;
+  --enable-fuse-lseek) fuse_lseek="enabled"
+  ;;
+  --disable-fuse-lseek) fuse_lseek="disabled"
+  ;;
   *)
       echo "ERROR: unknown option $opt"
       echo "Try '$0 --help' for more information"
@@ -1847,6 +1852,7 @@ disabled with --disable-FEATURE, default is enabled if available:
   rng-none        dummy RNG, avoid using /dev/(u)random and getrandom()
   libdaxctl       libdaxctl support
   fuse            FUSE block device export
+  fuse-lseek      SEEK_HOLE/SEEK_DATA support for FUSE exports
 
 NOTE: The object files are built at the place where configure is launched
 EOF
@@ -6988,7 +6994,7 @@ NINJA=$ninja $meson setup \
         -Dcapstone=$capstone -Dslirp=$slirp -Dfdt=$fdt \
         -Diconv=$iconv -Dcurses=$curses -Dlibudev=$libudev\
         -Ddocs=$docs -Dsphinx_build=$sphinx_build -Dinstall_blobs=$blobs \
-        -Dfuse=$fuse \
+        -Dfuse=$fuse -Dfuse_lseek=$fuse_lseek \
         $cross_arg \
         "$PWD" "$source_path"
 
diff --git a/meson.build b/meson.build
index 4e8436b456..ea1a68b46d 100644
--- a/meson.build
+++ b/meson.build
@@ -736,10 +736,28 @@ if not has_malloc_trim and get_option('malloc_trim').enabled()
   endif
 endif
 
+if get_option('fuse').disabled() and get_option('fuse_lseek').enabled()
+  error('Cannot enable fuse-lseek while fuse is disabled')
+endif
+
 fuse = dependency('fuse3', required: get_option('fuse'),
                   version: '>=3.1', method: 'pkg-config',
                   static: enable_static)
 
+fuse_lseek = not_found
+if not get_option('fuse_lseek').disabled()
+  if fuse.version().version_compare('>=3.8')
+    # Dummy dependency
+    fuse_lseek = declare_dependency()
+  elif get_option('fuse_lseek').enabled()
+    if fuse.found()
+      error('fuse-lseek requires libfuse >=3.8, found ' + fuse.version())
+    else
+      error('fuse-lseek requires libfuse, which was not found')
+    endif
+  endif
+endif
+
 #################
 # config-host.h #
 #################
@@ -773,6 +791,7 @@ config_host_data.set('CONFIG_KEYUTILS', keyutils.found())
 config_host_data.set('CONFIG_GETTID', has_gettid)
 config_host_data.set('CONFIG_MALLOC_TRIM', has_malloc_trim)
 config_host_data.set('CONFIG_FUSE', fuse.found())
+config_host_data.set('CONFIG_FUSE_LSEEK', fuse_lseek.found())
 config_host_data.set('QEMU_VERSION', '"@0@"'.format(meson.project_version()))
 config_host_data.set('QEMU_VERSION_MAJOR', meson.project_version().split('.')[0])
 config_host_data.set('QEMU_VERSION_MINOR', meson.project_version().split('.')[1])
@@ -2169,6 +2188,7 @@ summary_info += {'thread sanitizer':  config_host.has_key('CONFIG_TSAN')}
 summary_info += {'rng-none':          config_host.has_key('CONFIG_RNG_NONE')}
 summary_info += {'Linux keyring':     config_host.has_key('CONFIG_SECRET_KEYRING')}
 summary_info += {'FUSE exports':      fuse.found()}
+summary_info += {'FUSE lseek':        fuse_lseek.found()}
 summary(summary_info, bool_yn: true)
 
 if not supported_cpus.contains(cpu)
diff --git a/block/export/fuse.c b/block/export/fuse.c
index 0b9d226b2f..38f74c94da 100644
--- a/block/export/fuse.c
+++ b/block/export/fuse.c
@@ -627,6 +627,80 @@ static void fuse_flush(fuse_req_t req, fuse_ino_t inode,
     fuse_fsync(req, inode, 1, fi);
 }
 
+#ifdef CONFIG_FUSE_LSEEK
+/**
+ * Let clients inquire allocation status.
+ */
+static void fuse_lseek(fuse_req_t req, fuse_ino_t inode, off_t offset,
+                       int whence, struct fuse_file_info *fi)
+{
+    FuseExport *exp = fuse_req_userdata(req);
+
+    if (whence != SEEK_HOLE && whence != SEEK_DATA) {
+        fuse_reply_err(req, EINVAL);
+        return;
+    }
+
+    while (true) {
+        int64_t pnum;
+        int ret;
+
+        ret = bdrv_block_status_above(blk_bs(exp->common.blk), NULL,
+                                      offset, INT64_MAX, &pnum, NULL, NULL);
+        if (ret < 0) {
+            fuse_reply_err(req, -ret);
+            return;
+        }
+
+        if (!pnum && (ret & BDRV_BLOCK_EOF)) {
+            int64_t blk_len;
+
+            /*
+             * If blk_getlength() rounds (e.g. by sectors), then the
+             * export length will be rounded, too.  However,
+             * bdrv_block_status_above() may return EOF at unaligned
+             * offsets.  We must not let this become visible and thus
+             * always simulate a hole between @offset (the real EOF)
+             * and @blk_len (the client-visible EOF).
+             */
+
+            blk_len = blk_getlength(exp->common.blk);
+            if (blk_len < 0) {
+                fuse_reply_err(req, -blk_len);
+                return;
+            }
+
+            if (offset > blk_len || whence == SEEK_DATA) {
+                fuse_reply_err(req, ENXIO);
+            } else {
+                fuse_reply_lseek(req, offset);
+            }
+            return;
+        }
+
+        if (ret & BDRV_BLOCK_DATA) {
+            if (whence == SEEK_DATA) {
+                fuse_reply_lseek(req, offset);
+                return;
+            }
+        } else {
+            if (whence == SEEK_HOLE) {
+                fuse_reply_lseek(req, offset);
+                return;
+            }
+        }
+
+        /* Safety check against infinite loops */
+        if (!pnum) {
+            fuse_reply_err(req, ENXIO);
+            return;
+        }
+
+        offset += pnum;
+    }
+}
+#endif
+
 static const struct fuse_lowlevel_ops fuse_ops = {
     .init       = fuse_init,
     .lookup     = fuse_lookup,
@@ -638,6 +712,9 @@ static const struct fuse_lowlevel_ops fuse_ops = {
     .fallocate  = fuse_fallocate,
     .flush      = fuse_flush,
     .fsync      = fuse_fsync,
+#ifdef CONFIG_FUSE_LSEEK
+    .lseek      = fuse_lseek,
+#endif
 };
 
 const BlockExportDriver blk_exp_fuse = {
diff --git a/meson_options.txt b/meson_options.txt
index 2ef4ec628f..f9e7d89f9d 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -66,6 +66,8 @@ option('virtiofsd', type: 'feature', value: 'auto',
        description: 'build virtiofs daemon (virtiofsd)')
 option('fuse', type: 'feature', value: 'auto',
        description: 'FUSE block device export')
+option('fuse_lseek', type : 'feature', value : 'auto',
+       description: 'SEEK_HOLE/SEEK_DATA support for FUSE exports')
 
 option('capstone', type: 'combo', value: 'auto',
        choices: ['disabled', 'enabled', 'auto', 'system', 'internal'],
-- 
2.26.2

[PATCH for-6.0 v3 07/20] iotests: Do not needlessly filter _make_test_img

[Max Reitz]

In most cases, _make_test_img does not need a _filter_imgfmt on top.  It
does that by itself.

(The exception is when IMGFMT has been overwritten but TEST_IMG has not.
In such cases, we do need a _filter_imgfmt on top to filter the test's
original IMGFMT from TEST_IMG.)

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
---
 tests/qemu-iotests/161 | 12 ++++++------
 tests/qemu-iotests/175 |  6 +++---
 tests/qemu-iotests/249 |  6 +++---
 3 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/tests/qemu-iotests/161 b/tests/qemu-iotests/161
index e270976d87..bbf7dbbc5c 100755
--- a/tests/qemu-iotests/161
+++ b/tests/qemu-iotests/161
@@ -48,9 +48,9 @@ _supported_os Linux
 IMG_SIZE=1M
 
 # Create the images
-TEST_IMG="$TEST_IMG.base" _make_test_img $IMG_SIZE | _filter_imgfmt
-TEST_IMG="$TEST_IMG.int" _make_test_img -b "$TEST_IMG.base" -F $IMGFMT | _filter_imgfmt
-_make_test_img -b "$TEST_IMG.int" -F $IMGFMT -F $IMGFMT | _filter_imgfmt
+TEST_IMG="$TEST_IMG.base" _make_test_img $IMG_SIZE
+TEST_IMG="$TEST_IMG.int" _make_test_img -b "$TEST_IMG.base" -F $IMGFMT
+_make_test_img -b "$TEST_IMG.int" -F $IMGFMT -F $IMGFMT
 
 # First test: reopen $TEST.IMG changing the detect-zeroes option on
 # its backing file ($TEST_IMG.int).
@@ -105,9 +105,9 @@ echo
 echo "*** Commit and then change an option on the backing file"
 echo
 # Create the images again
-TEST_IMG="$TEST_IMG.base" _make_test_img $IMG_SIZE | _filter_imgfmt
-TEST_IMG="$TEST_IMG.int" _make_test_img -b "$TEST_IMG.base" -F $IMGFMT| _filter_imgfmt
-_make_test_img -b "$TEST_IMG.int" -F $IMGFMT | _filter_imgfmt
+TEST_IMG="$TEST_IMG.base" _make_test_img $IMG_SIZE
+TEST_IMG="$TEST_IMG.int" _make_test_img -b "$TEST_IMG.base" -F $IMGFMT
+_make_test_img -b "$TEST_IMG.int" -F $IMGFMT
 
 _launch_qemu -drive if=none,file="${TEST_IMG}"
 _send_qemu_cmd $QEMU_HANDLE \
diff --git a/tests/qemu-iotests/175 b/tests/qemu-iotests/175
index 00a626aa63..c3c2aed653 100755
--- a/tests/qemu-iotests/175
+++ b/tests/qemu-iotests/175
@@ -89,20 +89,20 @@ min_blocks=$(stat -c '%b' "$TEST_DIR/empty")
 
 echo
 echo "== creating image with default preallocation =="
-_make_test_img -o extent_size_hint=0 $size | _filter_imgfmt
+_make_test_img -o extent_size_hint=0 $size
 stat -c "size=%s, blocks=%b" $TEST_IMG | _filter_blocks $extra_blocks $min_blocks $size
 
 for mode in off full falloc; do
     echo
     echo "== creating image with preallocation $mode =="
-    _make_test_img -o preallocation=$mode,extent_size_hint=0 $size | _filter_imgfmt
+    _make_test_img -o preallocation=$mode,extent_size_hint=0 $size
     stat -c "size=%s, blocks=%b" $TEST_IMG | _filter_blocks $extra_blocks $min_blocks $size
 done
 
 for new_size in 4096 1048576; do
     echo
     echo "== resize empty image with block_resize =="
-    _make_test_img -o extent_size_hint=0 0 | _filter_imgfmt
+    _make_test_img -o extent_size_hint=0 0
     _block_resize $TEST_IMG $new_size >/dev/null
     stat -c "size=%s, blocks=%b" $TEST_IMG | _filter_blocks $extra_blocks $min_blocks $new_size
 done
diff --git a/tests/qemu-iotests/249 b/tests/qemu-iotests/249
index 68f13ed328..a9aa9303eb 100755
--- a/tests/qemu-iotests/249
+++ b/tests/qemu-iotests/249
@@ -48,9 +48,9 @@ _supported_os Linux
 IMG_SIZE=1M
 
 # Create the images: base <- int <- active
-TEST_IMG="$TEST_IMG.base" _make_test_img $IMG_SIZE | _filter_imgfmt
-TEST_IMG="$TEST_IMG.int" _make_test_img -b "$TEST_IMG.base" -F $IMGFMT | _filter_imgfmt
-_make_test_img -b "$TEST_IMG.int" -F $IMGFMT | _filter_imgfmt
+TEST_IMG="$TEST_IMG.base" _make_test_img $IMG_SIZE
+TEST_IMG="$TEST_IMG.int" _make_test_img -b "$TEST_IMG.base" -F $IMGFMT
+_make_test_img -b "$TEST_IMG.int" -F $IMGFMT
 
 # Launch QEMU with these two drives:
 # none0: base (read-only)
-- 
2.26.2

[PATCH for-6.0 v3 08/20] iotests: Do not pipe _make_test_img

[Max Reitz]

Executing _make_test_img as part of a pipe will undo all variable
changes it has done.  As such, this could not work with FUSE (because
we want to remember all of our exports and their qemu instances).

Replace the pipe by a temporary file in 071 and 174 (the two tests that
can run on FUSE).

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
---
 tests/qemu-iotests/071 | 19 +++++++++++++++----
 tests/qemu-iotests/174 | 10 +++++++++-
 2 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/tests/qemu-iotests/071 b/tests/qemu-iotests/071
index 88faebcc1d..18fe9054b0 100755
--- a/tests/qemu-iotests/071
+++ b/tests/qemu-iotests/071
@@ -61,8 +61,17 @@ echo
 echo "=== Testing blkverify through filename ==="
 echo
 
-TEST_IMG="$TEST_IMG.base" IMGFMT="raw" _make_test_img --no-opts $IMG_SIZE |\
-    _filter_imgfmt
+# _make_test_img may set variables that we need to retain.  Everything
+# in a pipe is executed in a subshell, so doing so would throw away
+# all changes.  Therefore, we have to store the output in some temp
+# file and filter that.
+scratch_out="$TEST_DIR/img-create.out"
+
+TEST_IMG="$TEST_IMG.base" IMGFMT="raw" _make_test_img --no-opts $IMG_SIZE \
+    >"$scratch_out"
+_filter_imgfmt <"$scratch_out"
+rm -f "$scratch_out"
+
 _make_test_img $IMG_SIZE
 $QEMU_IO -c "open -o driver=raw,file.driver=blkverify,file.raw.filename=$TEST_IMG.base $TEST_IMG" \
          -c 'read 0 512' -c 'write -P 42 0x38000 512' -c 'read -P 42 0x38000 512' | _filter_qemu_io
@@ -76,8 +85,10 @@ echo
 echo "=== Testing blkverify through file blockref ==="
 echo
 
-TEST_IMG="$TEST_IMG.base" IMGFMT="raw" _make_test_img --no-opts $IMG_SIZE |\
-    _filter_imgfmt
+TEST_IMG="$TEST_IMG.base" IMGFMT="raw" _make_test_img --no-opts $IMG_SIZE \
+    >"$scratch_out"
+_filter_imgfmt <"$scratch_out"
+
 _make_test_img $IMG_SIZE
 $QEMU_IO -c "open -o driver=raw,file.driver=blkverify,file.raw.filename=$TEST_IMG.base,file.test.driver=$IMGFMT,file.test.file.filename=$TEST_IMG" \
          -c 'read 0 512' -c 'write -P 42 0x38000 512' -c 'read -P 42 0x38000 512' | _filter_qemu_io
diff --git a/tests/qemu-iotests/174 b/tests/qemu-iotests/174
index e2f14a38c6..1b0dd2e8b7 100755
--- a/tests/qemu-iotests/174
+++ b/tests/qemu-iotests/174
@@ -40,7 +40,15 @@ _unsupported_fmt raw
 
 
 size=256K
-IMGFMT=raw IMGKEYSECRET= _make_test_img --no-opts $size | _filter_imgfmt
+
+# _make_test_img may set variables that we need to retain.  Everything
+# in a pipe is executed in a subshell, so doing so would throw away
+# all changes.  Therefore, we have to store the output in some temp
+# file and filter that.
+scratch_out="$TEST_DIR/img-create.out"
+IMGFMT=raw IMGKEYSECRET= _make_test_img --no-opts $size >"$scratch_out"
+_filter_imgfmt <"$scratch_out"
+rm -f "$scratch_out"
 
 echo
 echo "== reading wrong format should fail =="
-- 
2.26.2

[PATCH for-6.0 v3 09/20] iotests: Use convert -n in some cases

[Max Reitz]

qemu-img convert (without -n) can often be replaced by a combination of
_make_test_img + qemu-img convert -n.  Doing so allows converting to
protocols that do not allow direct file creation, such as FUSE exports.
The only problem is that for formats other than qcow2 and qed (qcow1 at
least), this may lead to high disk usage for some reason, so we cannot
do it everywhere.

But we can do it in 028 and 089, so let us do that so they can run on
FUSE exports.  Also, in 028 this allows us to remove a 9-line comment
that used to explain why we cannot safely filter drive-backup's image
creation output.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
---
 tests/qemu-iotests/028     | 14 ++++----------
 tests/qemu-iotests/028.out |  3 +++
 tests/qemu-iotests/089     |  3 ++-
 tests/qemu-iotests/089.out |  1 +
 4 files changed, 10 insertions(+), 11 deletions(-)

diff --git a/tests/qemu-iotests/028 b/tests/qemu-iotests/028
index 6dd3ae09a3..864dc4a4e2 100755
--- a/tests/qemu-iotests/028
+++ b/tests/qemu-iotests/028
@@ -116,16 +116,10 @@ else
     QEMU_COMM_TIMEOUT=1
 fi
 
-# Silence output since it contains the disk image path and QEMU's readline
-# character echoing makes it very hard to filter the output. Plus, there
-# is no telling how many times the command will repeat before succeeding.
-# (Note that creating the image results in a "Formatting..." message over
-# stdout, which is the same channel the monitor uses.  We cannot reliably
-# wait for it because the monitor output may interact with it in such a
-# way that _timed_wait_for cannot read it.  However, once the block job is
-# done, we know that the "Formatting..." message must have appeared
-# already, so the output is still deterministic.)
-silent=y _send_qemu_cmd $h "drive_backup disk ${TEST_IMG}.copy" "(qemu)"
+TEST_IMG="$TEST_IMG.copy" _make_test_img $image_size
+_send_qemu_cmd $h "drive_backup -n disk ${TEST_IMG}.copy" "(qemu)" \
+    | _filter_imgfmt
+
 silent=y qemu_cmd_repeat=20 _send_qemu_cmd $h "info block-jobs" "No active jobs"
 _send_qemu_cmd $h "info block-jobs" "No active jobs"
 _send_qemu_cmd $h 'quit' ""
diff --git a/tests/qemu-iotests/028.out b/tests/qemu-iotests/028.out
index 5a68de5c46..e580488216 100644
--- a/tests/qemu-iotests/028.out
+++ b/tests/qemu-iotests/028.out
@@ -468,6 +468,9 @@ No errors were found on the image.
 
 block-backup
 
+Formatting 'TEST_DIR/t.IMGFMT.copy', fmt=IMGFMT size=4294968832
+QEMU X.Y.Z monitor - type 'help' for more information
+(qemu) drive_backup -n disk TEST_DIR/t.IMGFMT.copy
 (qemu) info block-jobs
 No active jobs
 === IO: pattern 195
diff --git a/tests/qemu-iotests/089 b/tests/qemu-iotests/089
index 66c5415abe..03a2ccf1e8 100755
--- a/tests/qemu-iotests/089
+++ b/tests/qemu-iotests/089
@@ -62,7 +62,8 @@ TEST_IMG="$TEST_IMG.base" _make_test_img $IMG_SIZE
 $QEMU_IO -c 'write -P 42 0 512' -c 'write -P 23 512 512' \
          -c 'write -P 66 1024 512' "$TEST_IMG.base" | _filter_qemu_io
 
-$QEMU_IMG convert -f raw -O $IMGFMT "$TEST_IMG.base" "$TEST_IMG"
+_make_test_img $IMG_SIZE
+$QEMU_IMG convert -f raw -O $IMGFMT -n "$TEST_IMG.base" "$TEST_IMG"
 
 $QEMU_IO_PROG --cache $CACHEMODE --aio $AIOMODE \
          -c 'read -P 42 0 512' -c 'read -P 23 512 512' \
diff --git a/tests/qemu-iotests/089.out b/tests/qemu-iotests/089.out
index 15682c2886..c53fc4823a 100644
--- a/tests/qemu-iotests/089.out
+++ b/tests/qemu-iotests/089.out
@@ -9,6 +9,7 @@ wrote 512/512 bytes at offset 512
 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 wrote 512/512 bytes at offset 1024
 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
 read 512/512 bytes at offset 0
 512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 read 512/512 bytes at offset 512
-- 
2.26.2

[PATCH for-6.0 v3 10/20] iotests/046: Avoid renaming images

[Max Reitz]

This generally does not work on non-file protocols.  It is better to
create the image with the final name from the start, and most tests do
this already.  Let 046 follow suit.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
---
 tests/qemu-iotests/046     | 5 +++--
 tests/qemu-iotests/046.out | 2 +-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/tests/qemu-iotests/046 b/tests/qemu-iotests/046
index 88b3363c19..40a9f30087 100755
--- a/tests/qemu-iotests/046
+++ b/tests/qemu-iotests/046
@@ -47,6 +47,8 @@ size=128M
 echo
 echo "== creating backing file for COW tests =="
 
+TEST_IMG_SAVE=$TEST_IMG
+TEST_IMG="$TEST_IMG.base"
 _make_test_img $size
 
 backing_io()
@@ -67,8 +69,7 @@ backing_io()
 
 backing_io 0 32 write | $QEMU_IO "$TEST_IMG" | _filter_qemu_io
 
-mv "$TEST_IMG" "$TEST_IMG.base"
-
+TEST_IMG=$TEST_IMG_SAVE
 _make_test_img -b "$TEST_IMG.base" -F $IMGFMT 6G
 
 echo
diff --git a/tests/qemu-iotests/046.out b/tests/qemu-iotests/046.out
index b022bcddd5..66ad987ab3 100644
--- a/tests/qemu-iotests/046.out
+++ b/tests/qemu-iotests/046.out
@@ -1,7 +1,7 @@
 QA output created by 046
 
 == creating backing file for COW tests ==
-Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=134217728
+Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=134217728
 wrote 65536/65536 bytes at offset 0
 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 wrote 65536/65536 bytes at offset 65536
-- 
2.26.2

[PATCH for-6.0 v3 11/20] iotests: Derive image names from $TEST_IMG

[Max Reitz]

Avoid creating images with custom filenames in $TEST_DIR, because
non-file protocols may want to keep $TEST_IMG (and all other test
images) in some other directory.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
---
 tests/qemu-iotests/200     | 3 +--
 tests/qemu-iotests/200.out | 4 ++--
 tests/qemu-iotests/229     | 3 +--
 tests/qemu-iotests/229.out | 6 +++---
 4 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/tests/qemu-iotests/200 b/tests/qemu-iotests/200
index 59f7854b9f..a7aabbd032 100755
--- a/tests/qemu-iotests/200
+++ b/tests/qemu-iotests/200
@@ -44,8 +44,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 _supported_fmt qcow2 qed
 _supported_proto file
 
-BACKING_IMG="${TEST_DIR}/backing.img"
-TEST_IMG="${TEST_DIR}/test.img"
+BACKING_IMG="$TEST_IMG.base"
 
 TEST_IMG="$BACKING_IMG" _make_test_img 512M
 _make_test_img -F $IMGFMT -b "$BACKING_IMG" 512M
diff --git a/tests/qemu-iotests/200.out b/tests/qemu-iotests/200.out
index a6776070e4..5883f16ac3 100644
--- a/tests/qemu-iotests/200.out
+++ b/tests/qemu-iotests/200.out
@@ -1,6 +1,6 @@
 QA output created by 200
-Formatting 'TEST_DIR/backing.img', fmt=IMGFMT size=536870912
-Formatting 'TEST_DIR/test.img', fmt=IMGFMT size=536870912 backing_file=TEST_DIR/backing.img backing_fmt=IMGFMT
+Formatting 'TEST_DIR/t.IMGFMT.base', fmt=IMGFMT size=536870912
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=536870912 backing_file=TEST_DIR/t.IMGFMT.base backing_fmt=IMGFMT
 wrote 314572800/314572800 bytes at offset 512
 300 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 
diff --git a/tests/qemu-iotests/229 b/tests/qemu-iotests/229
index 89a5359f32..5f759fa587 100755
--- a/tests/qemu-iotests/229
+++ b/tests/qemu-iotests/229
@@ -51,8 +51,7 @@ _supported_os Linux
 _unsupported_imgopts data_file
 
 
-DEST_IMG="$TEST_DIR/d.$IMGFMT"
-TEST_IMG="$TEST_DIR/b.$IMGFMT"
+DEST_IMG="$TEST_IMG.dest"
 BLKDEBUG_CONF="$TEST_DIR/blkdebug.conf"
 
 _make_test_img 2M
diff --git a/tests/qemu-iotests/229.out b/tests/qemu-iotests/229.out
index 4de6dfaa28..7eed393013 100644
--- a/tests/qemu-iotests/229.out
+++ b/tests/qemu-iotests/229.out
@@ -1,6 +1,6 @@
 QA output created by 229
-Formatting 'TEST_DIR/b.IMGFMT', fmt=IMGFMT size=2097152
-Formatting 'TEST_DIR/d.IMGFMT', fmt=IMGFMT size=2097152
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=2097152
+Formatting 'TEST_DIR/t.IMGFMT.dest', fmt=IMGFMT size=2097152
 wrote 2097152/2097152 bytes at offset 0
 2 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 {'execute': 'qmp_capabilities'}
@@ -8,7 +8,7 @@ wrote 2097152/2097152 bytes at offset 0
 
 === Starting drive-mirror, causing error & stop  ===
 
-{'execute': 'drive-mirror', 'arguments': {'device': 'testdisk', 'format': 'IMGFMT', 'target': 'blkdebug:TEST_DIR/blkdebug.conf:TEST_DIR/d.IMGFMT', 'sync': 'full', 'mode': 'existing', 'on-source-error': 'stop', 'on-target-error': 'stop' }}
+{'execute': 'drive-mirror', 'arguments': {'device': 'testdisk', 'format': 'IMGFMT', 'target': 'blkdebug:TEST_DIR/blkdebug.conf:TEST_DIR/t.IMGFMT.dest', 'sync': 'full', 'mode': 'existing', 'on-source-error': 'stop', 'on-target-error': 'stop' }}
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "JOB_STATUS_CHANGE", "data": {"status": "created", "id": "testdisk"}}
 {"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "JOB_STATUS_CHANGE", "data": {"status": "running", "id": "testdisk"}}
 {"return": {}}
-- 
2.26.2

[PATCH for-6.0 v3 12/20] iotests/091: Use _cleanup_qemu instad of "wait"

[Max Reitz]

If the test environment has some other child processes running (like a
storage daemon that provides a FUSE export), then "wait" will never
finish.  Use wait=yes _cleanup_qemu instead.

(We need to discard the output so there is no change to the reference
output.)

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
---
 tests/qemu-iotests/091 | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tests/qemu-iotests/091 b/tests/qemu-iotests/091
index 68fbfd777b..8a4ce5b7e2 100755
--- a/tests/qemu-iotests/091
+++ b/tests/qemu-iotests/091
@@ -96,7 +96,8 @@ _send_qemu_cmd $h2 'qemu-io disk flush' "(qemu)"
 _send_qemu_cmd $h2 'quit' ""
 _send_qemu_cmd $h1 'quit' ""
 
-wait
+wait=yes _cleanup_qemu >/dev/null
+
 echo "Check image pattern"
 ${QEMU_IO} -c "read -P 0x22 0 4M" "${TEST_IMG}" | _filter_testdir | _filter_qemu_io
 
-- 
2.26.2

[PATCH for-6.0 v3 13/20] iotests: Restrict some Python tests to file

[Max Reitz]

Most Python tests are restricted to the file protocol (without
explicitly saying so), but these are the ones that would break
./check -fuse -qcow2.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
---
 tests/qemu-iotests/206 | 3 ++-
 tests/qemu-iotests/242 | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/tests/qemu-iotests/206 b/tests/qemu-iotests/206
index 11bc51f256..0a3ee5ef00 100755
--- a/tests/qemu-iotests/206
+++ b/tests/qemu-iotests/206
@@ -23,7 +23,8 @@
 import iotests
 from iotests import imgfmt
 
-iotests.script_initialize(supported_fmts=['qcow2'])
+iotests.script_initialize(supported_fmts=['qcow2'],
+                          supported_protocols=['file'])
 iotests.verify_working_luks()
 
 with iotests.FilePath('t.qcow2') as disk_path, \
diff --git a/tests/qemu-iotests/242 b/tests/qemu-iotests/242
index 64f1bd95e4..a16de3085f 100755
--- a/tests/qemu-iotests/242
+++ b/tests/qemu-iotests/242
@@ -24,7 +24,8 @@ import struct
 from iotests import qemu_img_create, qemu_io, qemu_img_pipe, \
     file_path, img_info_log, log, filter_qemu_io
 
-iotests.script_initialize(supported_fmts=['qcow2'])
+iotests.script_initialize(supported_fmts=['qcow2'],
+                          supported_protocols=['file'])
 
 disk = file_path('disk')
 chunk = 256 * 1024
-- 
2.26.2

[PATCH for-6.0 v3 14/20] iotests: Let _make_test_img guess $TEST_IMG_FILE

[Max Reitz]

When most iotests want to create a test image that is named differently
from the default $TEST_IMG, they do something like this:

    TEST_IMG="$TEST_IMG.base" _make_test_img $options

This works fine with the "file" protocol, but not so much for anything
else: _make_test_img tries to create an image under $TEST_IMG_FILE
first, and only under $TEST_IMG if the former is not set; and on
everything but "file", $TEST_IMG_FILE is set.

There are two ways we can fix this: First, we could make all tests
adjust not only TEST_IMG, but also TEST_IMG_FILE if that is present
(e.g. with something like _set_test_img_suffix $suffix that would affect
not only TEST_IMG but also TEST_IMG_FILE, if necessary).  This is a
pretty clean solution, and this is maybe what we should have done from
the start.

But it would also require changes to most existing bash tests.  So the
alternative is this: Let _make_test_img see whether $TEST_IMG_FILE still
points to the original value.  If so, it is possible that the caller has
adjusted $TEST_IMG but not $TEST_IMG_FILE.  In such a case, we can (for
most protocols) derive the corresponding $TEST_IMG_FILE value from
$TEST_IMG value and thus work around what technically is the caller
misbehaving.

This second solution is less clean, but it is robust against people
keeping their old habit of adjusting TEST_IMG only, and requires much
less changes.  So this patch implements it.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
---
 tests/qemu-iotests/common.rc | 40 +++++++++++++++++++++++++++++++++---
 1 file changed, 37 insertions(+), 3 deletions(-)

diff --git a/tests/qemu-iotests/common.rc b/tests/qemu-iotests/common.rc
index 494490a272..23f46da2db 100644
--- a/tests/qemu-iotests/common.rc
+++ b/tests/qemu-iotests/common.rc
@@ -268,6 +268,7 @@ else
         TEST_IMG=$IMGPROTO:$TEST_DIR/t.$IMGFMT
     fi
 fi
+ORIG_TEST_IMG_FILE=$TEST_IMG_FILE
 ORIG_TEST_IMG="$TEST_IMG"
 
 if [ -z "$TEST_DIR" ]; then
@@ -330,6 +331,30 @@ _get_data_file()
                     | sed -e "s#\\\$TEST_IMG#$1#"
 }
 
+# Translate a $TEST_IMG to its corresponding $TEST_IMG_FILE for
+# different protocols
+_test_img_to_test_img_file()
+{
+    case "$IMGPROTO" in
+        file)
+            echo "$1"
+            ;;
+
+        nfs)
+            echo "$1" | sed -e "s#nfs://127.0.0.1##"
+            ;;
+
+        ssh)
+            echo "$1" | \
+                sed -e "s#ssh://\\($USER@\\)\\?127.0.0.1\\(:[0-9]\\+\\)\\?##"
+            ;;
+
+        *)
+            return 1
+            ;;
+    esac
+}
+
 _make_test_img()
 {
     # extra qemu-img options can be added by tests
@@ -343,10 +368,19 @@ _make_test_img()
     local opts_param=false
     local misc_params=()
 
-    if [ -n "$TEST_IMG_FILE" ]; then
-        img_name=$TEST_IMG_FILE
-    else
+    if [ -z "$TEST_IMG_FILE" ]; then
         img_name=$TEST_IMG
+    elif [ "$IMGOPTSSYNTAX" != "true" -a \
+           "$TEST_IMG_FILE" = "$ORIG_TEST_IMG_FILE" ]; then
+        # Handle cases of tests only updating TEST_IMG, but not TEST_IMG_FILE
+        img_name=$(_test_img_to_test_img_file "$TEST_IMG")
+        if [ "$?" != 0 ]; then
+            img_name=$TEST_IMG_FILE
+        fi
+    else
+        # $TEST_IMG_FILE is not the default value, so it definitely has been
+        # modified by the test
+        img_name=$TEST_IMG_FILE
     fi
 
     if [ -n "$IMGOPTS" ]; then
-- 
2.26.2

[PATCH for-6.0 v3 15/20] iotests/287: Clean up subshell test image

[Max Reitz]

287 creates an image in a subshell (thanks to the pipe) to see whether
that is possible with compression_type=zstd.  If _make_test_img were to
modify any global state, this global state would then be lost before we
could cleanup the image.

When using FUSE as the test protocol, this global state is important, so
clean up the image before the state is lost.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
---
 tests/qemu-iotests/287 | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/qemu-iotests/287 b/tests/qemu-iotests/287
index f98a4cadc1..036cc09e82 100755
--- a/tests/qemu-iotests/287
+++ b/tests/qemu-iotests/287
@@ -51,8 +51,8 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 CLUSTER_SIZE=65536
 
 # Check if we can run this test.
-if IMGOPTS='compression_type=zstd' _make_test_img 64M |
-    grep "Invalid parameter 'zstd'"; then
+output=$(_make_test_img -o 'compression_type=zstd' 64M; _cleanup_test_img)
+if echo "$output" | grep -q "Invalid parameter 'zstd'"; then
     _notrun "ZSTD is disabled"
 fi
 
-- 
2.26.2

[PATCH for-6.0 v3 16/20] storage-daemon: Call bdrv_close_all() on exit

[Max Reitz]

Otherwise, exports and block devices are not properly shut down and
closed, unless the users explicitly issues blockdev-del and
block-export-del commands for each of them.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
---
 storage-daemon/qemu-storage-daemon.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/storage-daemon/qemu-storage-daemon.c b/storage-daemon/qemu-storage-daemon.c
index e419ba9f19..a213edea66 100644
--- a/storage-daemon/qemu-storage-daemon.c
+++ b/storage-daemon/qemu-storage-daemon.c
@@ -317,6 +317,9 @@ int main(int argc, char *argv[])
         main_loop_wait(false);
     }
 
+    bdrv_drain_all_begin();
+    bdrv_close_all();
+
     monitor_cleanup();
     qemu_chr_cleanup();
     user_creatable_cleanup();
-- 
2.26.2

[PATCH for-6.0 v3 17/20] iotests: Give access to the qemu-storage-daemon

[Max Reitz]

Signed-off-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/check     | 11 +++++++++++
 tests/qemu-iotests/common.rc | 17 +++++++++++++++++
 2 files changed, 28 insertions(+)

diff --git a/tests/qemu-iotests/check b/tests/qemu-iotests/check
index 678b6e4910..3c1fa4435a 100755
--- a/tests/qemu-iotests/check
+++ b/tests/qemu-iotests/check
@@ -644,6 +644,17 @@ if [ -z $QEMU_NBD_PROG ]; then
 fi
 export QEMU_NBD_PROG="$(type -p "$QEMU_NBD_PROG")"
 
+if [ -z "$QSD_PROG" ]; then
+    if [ -x "$build_iotests/qemu-storage-daemon" ]; then
+        export QSD_PROG="$build_iotests/qemu-storage-daemon"
+    elif [ -x "$build_root/storage-daemon/qemu-storage-daemon" ]; then
+        export QSD_PROG="$build_root/storage-daemon/qemu-storage-daemon"
+    else
+        _init_error "qemu-storage-daemon not found"
+    fi
+fi
+export QSD_PROG="$(type -p "$QSD_PROG")"
+
 if [ -x "$build_iotests/socket_scm_helper" ]
 then
     export SOCKET_SCM_HELPER="$build_iotests/socket_scm_helper"
diff --git a/tests/qemu-iotests/common.rc b/tests/qemu-iotests/common.rc
index 23f46da2db..20589e59a5 100644
--- a/tests/qemu-iotests/common.rc
+++ b/tests/qemu-iotests/common.rc
@@ -124,6 +124,7 @@ fi
 : ${VALGRIND_QEMU_IMG=$VALGRIND_QEMU}
 : ${VALGRIND_QEMU_IO=$VALGRIND_QEMU}
 : ${VALGRIND_QEMU_NBD=$VALGRIND_QEMU}
+: ${VALGRIND_QSD=$VALGRIND_QEMU}
 
 # The Valgrind own parameters may be set with
 # its environment variable VALGRIND_OPTS, e.g.
@@ -211,6 +212,21 @@ _qemu_nbd_wrapper()
     return $RETVAL
 }
 
+_qemu_storage_daemon_wrapper()
+{
+    local VALGRIND_LOGFILE="${TEST_DIR}"/$$.valgrind
+    (
+        if [ -n "${QSD_NEED_PID}" ]; then
+            echo $BASHPID > "${QEMU_TEST_DIR}/qemu-storage-daemon.pid"
+        fi
+        VALGRIND_QEMU="${VALGRIND_QSD}" _qemu_proc_exec "${VALGRIND_LOGFILE}" \
+            "$QSD_PROG" $QSD_OPTIONS "$@"
+    )
+    RETVAL=$?
+    _qemu_proc_valgrind_log "${VALGRIND_LOGFILE}" $RETVAL
+    return $RETVAL
+}
+
 # Valgrind bug #409141 https://bugs.kde.org/show_bug.cgi?id=409141
 # Until valgrind 3.16+ is ubiquitous, we must work around a hang in
 # valgrind when issuing sigkill. Disable valgrind for this invocation.
@@ -223,6 +239,7 @@ export QEMU=_qemu_wrapper
 export QEMU_IMG=_qemu_img_wrapper
 export QEMU_IO=_qemu_io_wrapper
 export QEMU_NBD=_qemu_nbd_wrapper
+export QSD=_qemu_storage_daemon_wrapper
 
 if [ "$IMGOPTSSYNTAX" = "true" ]; then
     DRIVER="driver=$IMGFMT"
-- 
2.26.2

[PATCH for-6.0 v3 18/20] iotests: Allow testing FUSE exports

[Max Reitz]

This pretends FUSE exports are a kind of protocol.  As such, they are
always tested under the format node.  This is probably the best way to
test them, actually, because this will generate more I/O load and more
varied patterns.

Signed-off-by: Max Reitz <mreitz@redhat.com>
---
 tests/qemu-iotests/check         |   6 ++
 tests/qemu-iotests/common.filter |   5 +-
 tests/qemu-iotests/common.rc     | 124 +++++++++++++++++++++++++++++++
 3 files changed, 134 insertions(+), 1 deletion(-)

diff --git a/tests/qemu-iotests/check b/tests/qemu-iotests/check
index 3c1fa4435a..952762d5ed 100755
--- a/tests/qemu-iotests/check
+++ b/tests/qemu-iotests/check
@@ -270,6 +270,7 @@ image protocol options
     -rbd                test rbd
     -sheepdog           test sheepdog
     -nbd                test nbd
+    -fuse               test fuse
     -ssh                test ssh
     -nfs                test nfs
 
@@ -382,6 +383,11 @@ testlist options
             xpand=false
             ;;
 
+        -fuse)
+            IMGPROTO=fuse
+            xpand=false
+            ;;
+
         -ssh)
             IMGPROTO=ssh
             xpand=false
diff --git a/tests/qemu-iotests/common.filter b/tests/qemu-iotests/common.filter
index 838ed15793..172ea5752e 100644
--- a/tests/qemu-iotests/common.filter
+++ b/tests/qemu-iotests/common.filter
@@ -44,7 +44,8 @@ _filter_qom_path()
 _filter_testdir()
 {
     $SED -e "s#$TEST_DIR/#TEST_DIR/#g" \
-         -e "s#$SOCK_DIR/#SOCK_DIR/#g"
+         -e "s#$SOCK_DIR/#SOCK_DIR/#g" \
+         -e "s#SOCK_DIR/fuse-#TEST_DIR/#g"
 }
 
 # replace occurrences of the actual IMGFMT value with IMGFMT
@@ -127,6 +128,7 @@ _filter_img_create_filenames()
         -e "s#$IMGPROTO:$TEST_DIR#TEST_DIR#g" \
         -e "s#$TEST_DIR#TEST_DIR#g" \
         -e "s#$SOCK_DIR#SOCK_DIR#g" \
+        -e 's#SOCK_DIR/fuse-#TEST_DIR/#g' \
         -e "s#$IMGFMT#IMGFMT#g" \
         -e 's#nbd:127.0.0.1:[0-9]\\+#TEST_DIR/t.IMGFMT#g' \
         -e 's#nbd+unix:///\??socket=SOCK_DIR/nbd#TEST_DIR/t.IMGFMT#g'
@@ -227,6 +229,7 @@ _filter_img_info()
         -e "s#$IMGFMT#IMGFMT#g" \
         -e 's#nbd://127.0.0.1:[0-9]\\+$#TEST_DIR/t.IMGFMT#g' \
         -e 's#nbd+unix:///\??socket=SOCK_DIR/nbd#TEST_DIR/t.IMGFMT#g' \
+        -e 's#SOCK_DIR/fuse-#TEST_DIR/#g' \
         -e "/encrypted: yes/d" \
         -e "/cluster_size: [0-9]\\+/d" \
         -e "/table_size: [0-9]\\+/d" \
diff --git a/tests/qemu-iotests/common.rc b/tests/qemu-iotests/common.rc
index 20589e59a5..29354654cc 100644
--- a/tests/qemu-iotests/common.rc
+++ b/tests/qemu-iotests/common.rc
@@ -257,6 +257,9 @@ if [ "$IMGOPTSSYNTAX" = "true" ]; then
         TEST_IMG_FILE=$TEST_DIR/t.$IMGFMT
         TEST_IMG="$DRIVER,file.driver=nbd,file.type=unix"
         TEST_IMG="$TEST_IMG,file.path=$SOCK_DIR/nbd"
+    elif [ "$IMGPROTO" = "fuse" ]; then
+        TEST_IMG_FILE=$TEST_DIR/t.$IMGFMT
+        TEST_IMG="$DRIVER,file.filename=$SOCK_DIR/fuse-t.$IMGFMT"
     elif [ "$IMGPROTO" = "ssh" ]; then
         TEST_IMG_FILE=$TEST_DIR/t.$IMGFMT
         TEST_IMG="$DRIVER,file.driver=ssh,file.host=127.0.0.1,file.path=$TEST_IMG_FILE"
@@ -273,6 +276,9 @@ else
     elif [ "$IMGPROTO" = "nbd" ]; then
         TEST_IMG_FILE=$TEST_DIR/t.$IMGFMT
         TEST_IMG="nbd+unix:///?socket=$SOCK_DIR/nbd"
+    elif [ "$IMGPROTO" = "fuse" ]; then
+        TEST_IMG_FILE=$TEST_DIR/t.$IMGFMT
+        TEST_IMG="$SOCK_DIR/fuse-t.$IMGFMT"
     elif [ "$IMGPROTO" = "ssh" ]; then
         TEST_IMG_FILE=$TEST_DIR/t.$IMGFMT
         REMOTE_TEST_DIR="ssh://\\($USER@\\)\\?127.0.0.1\\(:[0-9]\\+\\)\\?$TEST_DIR"
@@ -288,6 +294,9 @@ fi
 ORIG_TEST_IMG_FILE=$TEST_IMG_FILE
 ORIG_TEST_IMG="$TEST_IMG"
 
+FUSE_PIDS=()
+FUSE_EXPORTS=()
+
 if [ -z "$TEST_DIR" ]; then
         TEST_DIR=$PWD/scratch
 fi
@@ -357,6 +366,10 @@ _test_img_to_test_img_file()
             echo "$1"
             ;;
 
+        fuse)
+            echo "$1" | sed -e "s#$SOCK_DIR/fuse-#$TEST_DIR/#"
+            ;;
+
         nfs)
             echo "$1" | sed -e "s#nfs://127.0.0.1##"
             ;;
@@ -385,6 +398,11 @@ _make_test_img()
     local opts_param=false
     local misc_params=()
 
+    if [[ $IMGPROTO == fuse && $TEST_IMG == $SOCK_DIR/fuse-* ]]; then
+        # The caller may be trying to overwrite an existing image
+        _rm_test_img "$TEST_IMG"
+    fi
+
     if [ -z "$TEST_IMG_FILE" ]; then
         img_name=$TEST_IMG
     elif [ "$IMGOPTSSYNTAX" != "true" -a \
@@ -469,11 +487,105 @@ _make_test_img()
         eval "$QEMU_NBD -v -t -k '$SOCK_DIR/nbd' -f $IMGFMT -e 42 -x '' $TEST_IMG_FILE >/dev/null &"
         sleep 1 # FIXME: qemu-nbd needs to be listening before we continue
     fi
+
+    if [ $IMGPROTO = "fuse" -a -f "$img_name" ]; then
+        local export_mp
+        local pid
+        local pidfile
+        local timeout
+
+        export_mp=$(echo "$img_name" | sed -e "s#$TEST_DIR/#$SOCK_DIR/fuse-#")
+        if ! echo "$export_mp" | grep -q "^$SOCK_DIR"; then
+            echo 'Cannot use FUSE exports with images outside of TEST_DIR' >&2
+            return 1
+        fi
+
+        touch "$export_mp"
+        rm -f "$SOCK_DIR/fuse-output"
+
+        # Usually, users would export formatted nodes.  But we present fuse as a
+        # protocol-level driver here, so we have to leave the format to the
+        # client.
+        QSD_NEED_PID=y $QSD \
+              --blockdev file,node-name=export-node,filename=$img_name,discard=unmap \
+              --export fuse,id=fuse-export,node-name=export-node,mountpoint="$export_mp",writable=on,growable=on \
+              &
+
+        pidfile="$QEMU_TEST_DIR/qemu-storage-daemon.pid"
+
+        # Wait for the PID file
+        while [ ! -f "$pidfile" ]; do
+            sleep 0.5
+        done
+
+        pid=$(cat "$pidfile")
+        rm -f "$pidfile"
+
+        FUSE_PIDS+=($pid)
+        FUSE_EXPORTS+=("$export_mp")
+    fi
 }
 
 _rm_test_img()
 {
     local img=$1
+
+    if [[ $IMGPROTO == fuse && $img == $SOCK_DIR/fuse-* ]]; then
+        # Drop a FUSE export
+        local df_output
+        local i
+        local image_file
+        local index=''
+        local timeout
+
+        for i in "${!FUSE_EXPORTS[@]}"; do
+            if [ "${FUSE_EXPORTS[i]}" = "$img" ]; then
+                index=$i
+                break
+            fi
+        done
+
+        if [ -z "$index" ]; then
+            # Probably gone already
+            return 0
+        fi
+
+        kill "${FUSE_PIDS[index]}"
+
+        # Wait until the mount is gone
+        timeout=10 # *0.5 s
+        while true; do
+            # Will show the mount point; if the mount is still there,
+            # it will be $img.
+            df_output=$(df "$img" 2>/dev/null)
+
+            # But df may also show an error ("Transpoint endpoint not
+            # connected"), so retry in such cases
+            if [ -n "$df_output" ]; then
+                if ! echo "$df_output" | grep -q "$img"; then
+                    break
+                fi
+            fi
+
+            sleep 0.5
+
+            timeout=$((timeout - 1))
+            if [ "$timeout" = 0 ]; then
+                echo 'Failed to take down FUSE export' >&2
+                return 1
+            fi
+        done
+
+        rm -f "$img"
+
+        unset "FUSE_PIDS[$index]"
+        unset "FUSE_EXPORTS[$index]"
+
+        image_file=$(echo "$img" | sed -e "s#$SOCK_DIR/fuse-#$TEST_DIR/#")
+        _rm_test_img "$image_file"
+        return
+    fi
+
     if [ "$IMGFMT" = "vmdk" ]; then
         # Remove all the extents for vmdk
         "$QEMU_IMG" info "$img" 2>/dev/null | grep 'filename:' | cut -f 2 -d: \
@@ -496,6 +608,17 @@ _cleanup_test_img()
             rm -f "$TEST_IMG_FILE"
             ;;
 
+        fuse)
+            local mp
+
+            for mp in "${FUSE_EXPORTS[@]}"; do
+                _rm_test_img "$mp"
+            done
+
+            FUSE_PIDS=()
+            FUSE_EXPORTS=()
+            ;;
+
         file)
             _rm_test_img "$TEST_DIR/t.$IMGFMT"
             _rm_test_img "$TEST_DIR/t.$IMGFMT.orig"
@@ -562,6 +685,7 @@ _img_info()
         sed -e "s#$REMOTE_TEST_DIR#TEST_DIR#g" \
             -e "s#$IMGPROTO:$TEST_DIR#TEST_DIR#g" \
             -e "s#$TEST_DIR#TEST_DIR#g" \
+            -e "s#$SOCK_DIR/fuse-#TEST_DIR/#g" \
             -e "s#$IMGFMT#IMGFMT#g" \
             -e "/^disk size:/ D" \
             -e "/actual-size/ D" | \
-- 
2.26.2

[PATCH for-6.0 v3 19/20] iotests: Enable fuse for many tests

[Max Reitz]

Many tests (that do not support generic protocols) can run just fine
with FUSE-exported images, so allow them to.  Note that this is no
attempt at being definitely complete.  There are some tests that might
be modified to run on FUSE, but this patch still skips them.  This patch
only tries to pick the rather low-hanging fruits.

Note that 221 and 250 only pass when .lseek is correctly implemented,
which is only possible with a libfuse that is 3.8 or newer.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
---
 tests/qemu-iotests/025 | 2 +-
 tests/qemu-iotests/026 | 2 +-
 tests/qemu-iotests/028 | 2 +-
 tests/qemu-iotests/031 | 2 +-
 tests/qemu-iotests/034 | 2 +-
 tests/qemu-iotests/036 | 2 +-
 tests/qemu-iotests/037 | 2 +-
 tests/qemu-iotests/038 | 2 +-
 tests/qemu-iotests/039 | 2 +-
 tests/qemu-iotests/046 | 2 +-
 tests/qemu-iotests/050 | 2 +-
 tests/qemu-iotests/054 | 2 +-
 tests/qemu-iotests/060 | 2 +-
 tests/qemu-iotests/071 | 2 +-
 tests/qemu-iotests/079 | 2 +-
 tests/qemu-iotests/080 | 2 +-
 tests/qemu-iotests/089 | 2 +-
 tests/qemu-iotests/090 | 2 +-
 tests/qemu-iotests/091 | 2 +-
 tests/qemu-iotests/095 | 2 +-
 tests/qemu-iotests/097 | 2 +-
 tests/qemu-iotests/098 | 2 +-
 tests/qemu-iotests/102 | 2 +-
 tests/qemu-iotests/103 | 2 +-
 tests/qemu-iotests/106 | 2 +-
 tests/qemu-iotests/107 | 2 +-
 tests/qemu-iotests/108 | 2 +-
 tests/qemu-iotests/111 | 2 +-
 tests/qemu-iotests/112 | 2 +-
 tests/qemu-iotests/115 | 2 +-
 tests/qemu-iotests/117 | 2 +-
 tests/qemu-iotests/120 | 2 +-
 tests/qemu-iotests/121 | 2 +-
 tests/qemu-iotests/127 | 2 +-
 tests/qemu-iotests/133 | 2 +-
 tests/qemu-iotests/137 | 2 +-
 tests/qemu-iotests/138 | 2 +-
 tests/qemu-iotests/140 | 2 +-
 tests/qemu-iotests/154 | 2 +-
 tests/qemu-iotests/161 | 2 +-
 tests/qemu-iotests/171 | 2 +-
 tests/qemu-iotests/175 | 2 +-
 tests/qemu-iotests/176 | 2 +-
 tests/qemu-iotests/177 | 2 +-
 tests/qemu-iotests/179 | 2 +-
 tests/qemu-iotests/183 | 2 +-
 tests/qemu-iotests/186 | 2 +-
 tests/qemu-iotests/187 | 2 +-
 tests/qemu-iotests/191 | 2 +-
 tests/qemu-iotests/195 | 2 +-
 tests/qemu-iotests/200 | 2 +-
 tests/qemu-iotests/204 | 2 +-
 tests/qemu-iotests/214 | 2 +-
 tests/qemu-iotests/217 | 2 +-
 tests/qemu-iotests/220 | 2 +-
 tests/qemu-iotests/221 | 2 +-
 tests/qemu-iotests/229 | 2 +-
 tests/qemu-iotests/247 | 2 +-
 tests/qemu-iotests/249 | 2 +-
 tests/qemu-iotests/250 | 2 +-
 tests/qemu-iotests/252 | 2 +-
 tests/qemu-iotests/265 | 2 +-
 tests/qemu-iotests/268 | 2 +-
 tests/qemu-iotests/272 | 2 +-
 tests/qemu-iotests/273 | 2 +-
 tests/qemu-iotests/279 | 2 +-
 tests/qemu-iotests/286 | 2 +-
 tests/qemu-iotests/287 | 2 +-
 tests/qemu-iotests/289 | 2 +-
 tests/qemu-iotests/290 | 2 +-
 tests/qemu-iotests/291 | 2 +-
 tests/qemu-iotests/292 | 2 +-
 tests/qemu-iotests/293 | 2 +-
 tests/qemu-iotests/294 | 2 +-
 tests/qemu-iotests/305 | 2 +-
 75 files changed, 75 insertions(+), 75 deletions(-)

diff --git a/tests/qemu-iotests/025 b/tests/qemu-iotests/025
index e05d833452..1569d912f4 100755
--- a/tests/qemu-iotests/025
+++ b/tests/qemu-iotests/025
@@ -38,7 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.pattern
 
 _supported_fmt raw qcow2 qed luks
-_supported_proto file sheepdog rbd nfs
+_supported_proto file sheepdog rbd nfs fuse
 
 echo "=== Creating image"
 echo
diff --git a/tests/qemu-iotests/026 b/tests/qemu-iotests/026
index b9713eb591..9ecc5880b1 100755
--- a/tests/qemu-iotests/026
+++ b/tests/qemu-iotests/026
@@ -41,7 +41,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # Currently only qcow2 supports rebasing
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _default_cache_mode writethrough
 _supported_cache_modes writethrough none
 # The refcount table tests expect a certain minimum width for refcount entries
diff --git a/tests/qemu-iotests/028 b/tests/qemu-iotests/028
index 864dc4a4e2..57d34aae99 100755
--- a/tests/qemu-iotests/028
+++ b/tests/qemu-iotests/028
@@ -46,7 +46,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 # Any format supporting backing files except vmdk and qcow which do not support
 # smaller backing files.
 _supported_fmt qcow2 qed
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 
 # Choose a size that is not necessarily a cluster size multiple for image
diff --git a/tests/qemu-iotests/031 b/tests/qemu-iotests/031
index 646ecd593f..2bcbc5886e 100755
--- a/tests/qemu-iotests/031
+++ b/tests/qemu-iotests/031
@@ -39,7 +39,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # This tests qcow2-specific low-level functionality
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 # We want to test compat=0.10, which does not support external data
 # files or refcount widths other than 16
 _unsupported_imgopts data_file 'refcount_bits=\([^1]\|.\([^6]\|$\)\)'
diff --git a/tests/qemu-iotests/034 b/tests/qemu-iotests/034
index ac2d687c71..08f7aea6d5 100755
--- a/tests/qemu-iotests/034
+++ b/tests/qemu-iotests/034
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow qcow2 vmdk qed
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 _unsupported_imgopts "subformat=monolithicFlat" \
                      "subformat=twoGbMaxExtentFlat" \
diff --git a/tests/qemu-iotests/036 b/tests/qemu-iotests/036
index cf522de7a1..6b82638080 100755
--- a/tests/qemu-iotests/036
+++ b/tests/qemu-iotests/036
@@ -42,7 +42,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # This tests qcow2-specific low-level functionality
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 # Only qcow2v3 and later supports feature bits;
 # qcow2.py does not support external data files;
 # this test requires a cluster size large enough for the feature table
diff --git a/tests/qemu-iotests/037 b/tests/qemu-iotests/037
index e1187ac24a..bb893c43dc 100755
--- a/tests/qemu-iotests/037
+++ b/tests/qemu-iotests/037
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow qcow2 vmdk qed
-_supported_proto file
+_supported_proto file fuse
 _unsupported_imgopts "subformat=monolithicFlat" \
                      "subformat=twoGbMaxExtentFlat" \
                      "subformat=twoGbMaxExtentSparse" \
diff --git a/tests/qemu-iotests/038 b/tests/qemu-iotests/038
index a253231f5b..30f1f73c25 100755
--- a/tests/qemu-iotests/038
+++ b/tests/qemu-iotests/038
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2 qed
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 
 CLUSTER_SIZE=2M
diff --git a/tests/qemu-iotests/039 b/tests/qemu-iotests/039
index 42f6503138..ad3867c3fc 100755
--- a/tests/qemu-iotests/039
+++ b/tests/qemu-iotests/039
@@ -40,7 +40,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 _default_cache_mode writethrough
 _supported_cache_modes writethrough
diff --git a/tests/qemu-iotests/046 b/tests/qemu-iotests/046
index 40a9f30087..ed6fae3529 100755
--- a/tests/qemu-iotests/046
+++ b/tests/qemu-iotests/046
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 # data_file does not support compressed clusters
 _unsupported_imgopts data_file
 
diff --git a/tests/qemu-iotests/050 b/tests/qemu-iotests/050
index 4b0a390c43..741bdb610e 100755
--- a/tests/qemu-iotests/050
+++ b/tests/qemu-iotests/050
@@ -39,7 +39,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2 qed
-_supported_proto file
+_supported_proto file fuse
 
 echo
 echo "== Creating images =="
diff --git a/tests/qemu-iotests/054 b/tests/qemu-iotests/054
index a8905b60d0..40922db2b1 100755
--- a/tests/qemu-iotests/054
+++ b/tests/qemu-iotests/054
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 
 echo
 echo "creating too large image (1 EB)"
diff --git a/tests/qemu-iotests/060 b/tests/qemu-iotests/060
index 94c0d5accc..4b81d1aa51 100755
--- a/tests/qemu-iotests/060
+++ b/tests/qemu-iotests/060
@@ -46,7 +46,7 @@ _filter_io_error()
 
 # This tests qcow2-specific low-level functionality
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 # These tests only work for compat=1.1 images without an external
 # data file with refcount_bits=16
diff --git a/tests/qemu-iotests/071 b/tests/qemu-iotests/071
index 18fe9054b0..49faae6684 100755
--- a/tests/qemu-iotests/071
+++ b/tests/qemu-iotests/071
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _require_drivers blkdebug blkverify
 # blkdebug can only inject errors on bs->file, not on the data_file,
 # so thie test does not work with external data files
diff --git a/tests/qemu-iotests/079 b/tests/qemu-iotests/079
index 3642b51feb..0f0d94a2ac 100755
--- a/tests/qemu-iotests/079
+++ b/tests/qemu-iotests/079
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file nfs
+_supported_proto file nfs fuse
 
 # Some containers (e.g. non-x86 on Travis) do not allow large files
 _require_large_file 4G
diff --git a/tests/qemu-iotests/080 b/tests/qemu-iotests/080
index 7588c63b6c..bda8617c38 100755
--- a/tests/qemu-iotests/080
+++ b/tests/qemu-iotests/080
@@ -38,7 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 # - Internal snapshots are (currently) impossible with refcount_bits=1,
 #   and generally impossible with external data files
diff --git a/tests/qemu-iotests/089 b/tests/qemu-iotests/089
index 03a2ccf1e8..f0929b64c0 100755
--- a/tests/qemu-iotests/089
+++ b/tests/qemu-iotests/089
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 # Because anything other than 16 would change the output of qemu_io -c info
 _unsupported_imgopts 'refcount_bits=\([^1]\|.\([^6]\|$\)\)'
 
diff --git a/tests/qemu-iotests/090 b/tests/qemu-iotests/090
index 1246e4f910..87e872ebf4 100755
--- a/tests/qemu-iotests/090
+++ b/tests/qemu-iotests/090
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file nfs
+_supported_proto file nfs fuse
 # External data files do not support compressed clusters
 _unsupported_imgopts data_file
 
diff --git a/tests/qemu-iotests/091 b/tests/qemu-iotests/091
index 8a4ce5b7e2..8dee168bf6 100755
--- a/tests/qemu-iotests/091
+++ b/tests/qemu-iotests/091
@@ -44,7 +44,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.qemu
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 _supported_cache_modes writethrough none writeback
 _default_cache_mode none writeback
diff --git a/tests/qemu-iotests/095 b/tests/qemu-iotests/095
index 77a5f0f3f5..7604ae6966 100755
--- a/tests/qemu-iotests/095
+++ b/tests/qemu-iotests/095
@@ -44,7 +44,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.qemu
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 
 size_smaller=5M
 size_larger=100M
diff --git a/tests/qemu-iotests/097 b/tests/qemu-iotests/097
index d910a8b107..1837d4e8e0 100755
--- a/tests/qemu-iotests/097
+++ b/tests/qemu-iotests/097
@@ -41,7 +41,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # Any format supporting backing files and bdrv_make_empty
 _supported_fmt qcow qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 
 
diff --git a/tests/qemu-iotests/098 b/tests/qemu-iotests/098
index f2ccdd7909..a35ce7205e 100755
--- a/tests/qemu-iotests/098
+++ b/tests/qemu-iotests/098
@@ -39,7 +39,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.pattern
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 # The code path we want to test here only works for compat=1.1 images;
 # blkdebug can only inject errors on bs->file, so external data files
 # do not work with this test
diff --git a/tests/qemu-iotests/102 b/tests/qemu-iotests/102
index b898df436f..2cc3efd1ed 100755
--- a/tests/qemu-iotests/102
+++ b/tests/qemu-iotests/102
@@ -39,7 +39,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.qemu
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 
 IMG_SIZE=64K
 
diff --git a/tests/qemu-iotests/103 b/tests/qemu-iotests/103
index 8c1ebe0443..220481db4c 100755
--- a/tests/qemu-iotests/103
+++ b/tests/qemu-iotests/103
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file nfs
+_supported_proto file nfs fuse
 # Internal snapshots are (currently) impossible with refcount_bits=1,
 # and generally impossible with external data files
 _unsupported_imgopts 'refcount_bits=1[^0-9]' data_file
diff --git a/tests/qemu-iotests/106 b/tests/qemu-iotests/106
index a20659d443..20ad7bd5a2 100755
--- a/tests/qemu-iotests/106
+++ b/tests/qemu-iotests/106
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt raw
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 
 # in kB
diff --git a/tests/qemu-iotests/107 b/tests/qemu-iotests/107
index 268ba27688..d24829ccf9 100755
--- a/tests/qemu-iotests/107
+++ b/tests/qemu-iotests/107
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file nfs
+_supported_proto file nfs fuse
 
 
 IMG_SIZE=64K
diff --git a/tests/qemu-iotests/108 b/tests/qemu-iotests/108
index 5f7076fba4..ba67748bdf 100755
--- a/tests/qemu-iotests/108
+++ b/tests/qemu-iotests/108
@@ -39,7 +39,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # This tests qcow2-specific low-level functionality
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 # This test directly modifies a refblock so it relies on refcount_bits being 16;
 # and the low-level modification it performs are not tuned for external data
diff --git a/tests/qemu-iotests/111 b/tests/qemu-iotests/111
index 3b43d1bd83..bd839a39f4 100755
--- a/tests/qemu-iotests/111
+++ b/tests/qemu-iotests/111
@@ -38,7 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qed qcow qcow2 vmdk
-_supported_proto file
+_supported_proto file fuse
 _unsupported_imgopts "subformat=monolithicFlat" "subformat=twoGbMaxExtentFlat"
 
 _make_test_img -b "$TEST_IMG.inexistent"
diff --git a/tests/qemu-iotests/112 b/tests/qemu-iotests/112
index 20ff5c224a..6e413f5651 100755
--- a/tests/qemu-iotests/112
+++ b/tests/qemu-iotests/112
@@ -38,7 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # This tests qcow2-specific low-level functionality
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 # This test will set refcount_bits on its own which would conflict with the
 # manual setting; compat will be overridden as well;
 # and external data files do not work well with our refcount testing
diff --git a/tests/qemu-iotests/115 b/tests/qemu-iotests/115
index d254b18342..7f53987d1b 100755
--- a/tests/qemu-iotests/115
+++ b/tests/qemu-iotests/115
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 # This test relies on refcounts being 64 bits wide (which does not work with
 # compat=0.10)
 _unsupported_imgopts 'refcount_bits=\([^6]\|.\([^4]\|$\)\)' 'compat=0.10'
diff --git a/tests/qemu-iotests/117 b/tests/qemu-iotests/117
index f37b34f8b1..9039555ac4 100755
--- a/tests/qemu-iotests/117
+++ b/tests/qemu-iotests/117
@@ -39,7 +39,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.qemu
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 
 _make_test_img 64k
 
diff --git a/tests/qemu-iotests/120 b/tests/qemu-iotests/120
index 2931a7550f..45c55c1c01 100755
--- a/tests/qemu-iotests/120
+++ b/tests/qemu-iotests/120
@@ -38,7 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt generic
-_supported_proto file
+_supported_proto file fuse
 _unsupported_fmt luks
 _require_drivers raw
 
diff --git a/tests/qemu-iotests/121 b/tests/qemu-iotests/121
index 90ea0db737..8357ce089a 100755
--- a/tests/qemu-iotests/121
+++ b/tests/qemu-iotests/121
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 # Refcount structures are used much differently with external data
 # files
diff --git a/tests/qemu-iotests/127 b/tests/qemu-iotests/127
index e2ac2f5536..77fdfd0205 100755
--- a/tests/qemu-iotests/127
+++ b/tests/qemu-iotests/127
@@ -41,7 +41,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.qemu
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 
 _require_devices virtio-scsi scsi-hd
 
diff --git a/tests/qemu-iotests/133 b/tests/qemu-iotests/133
index 4070fd9457..bc82d8ebd7 100755
--- a/tests/qemu-iotests/133
+++ b/tests/qemu-iotests/133
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 
 TEST_IMG="$TEST_IMG.base" _make_test_img 64M
 _make_test_img -b "$TEST_IMG.base" -F $IMGFMT
diff --git a/tests/qemu-iotests/137 b/tests/qemu-iotests/137
index 7ae86892f7..de555a91c9 100755
--- a/tests/qemu-iotests/137
+++ b/tests/qemu-iotests/137
@@ -38,7 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.qemu
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 # We are going to use lazy-refcounts
 _unsupported_imgopts 'compat=0.10'
diff --git a/tests/qemu-iotests/138 b/tests/qemu-iotests/138
index 1d5b0bed6d..e87a64eb89 100755
--- a/tests/qemu-iotests/138
+++ b/tests/qemu-iotests/138
@@ -38,7 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # This tests qcow2-specific low-level functionality
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 # With an external data file, data clusters are not refcounted
 # (so qemu-img check would not do much);
diff --git a/tests/qemu-iotests/140 b/tests/qemu-iotests/140
index 309b177e77..ff6b904fa0 100755
--- a/tests/qemu-iotests/140
+++ b/tests/qemu-iotests/140
@@ -44,7 +44,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.qemu
 
 _supported_fmt generic
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 
 _make_test_img 64k
diff --git a/tests/qemu-iotests/154 b/tests/qemu-iotests/154
index 7f1c0d9bd9..34a1c051b6 100755
--- a/tests/qemu-iotests/154
+++ b/tests/qemu-iotests/154
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 
 CLUSTER_SIZE=4k
diff --git a/tests/qemu-iotests/161 b/tests/qemu-iotests/161
index bbf7dbbc5c..4fb7d0cbf0 100755
--- a/tests/qemu-iotests/161
+++ b/tests/qemu-iotests/161
@@ -42,7 +42,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # Any format implementing BlockDriver.bdrv_change_backing_file
 _supported_fmt qcow2 qed
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 
 IMG_SIZE=1M
diff --git a/tests/qemu-iotests/171 b/tests/qemu-iotests/171
index 341064a1c6..f3582edb10 100755
--- a/tests/qemu-iotests/171
+++ b/tests/qemu-iotests/171
@@ -38,7 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt raw
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 
 
diff --git a/tests/qemu-iotests/175 b/tests/qemu-iotests/175
index c3c2aed653..21a77a2bf5 100755
--- a/tests/qemu-iotests/175
+++ b/tests/qemu-iotests/175
@@ -71,7 +71,7 @@ EOF
 . ./common.filter
 
 _supported_fmt raw
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 
 _default_cache_mode none
diff --git a/tests/qemu-iotests/176 b/tests/qemu-iotests/176
index 2565ff12ee..5ce3b27069 100755
--- a/tests/qemu-iotests/176
+++ b/tests/qemu-iotests/176
@@ -45,7 +45,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # This test is specific to qcow2
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 # Persistent dirty bitmaps require compat=1.1;
 # Internal snapshots forbid using an external data file
diff --git a/tests/qemu-iotests/177 b/tests/qemu-iotests/177
index 5d4a77a6ab..595bfd4236 100755
--- a/tests/qemu-iotests/177
+++ b/tests/qemu-iotests/177
@@ -40,7 +40,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 # tests specific to compat=1.1.
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 
 CLUSTER_SIZE=1M
 size=128M
diff --git a/tests/qemu-iotests/179 b/tests/qemu-iotests/179
index 11a20cb1bf..7ada04c641 100755
--- a/tests/qemu-iotests/179
+++ b/tests/qemu-iotests/179
@@ -38,7 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 
 # v2 images can't mark clusters as zero
diff --git a/tests/qemu-iotests/183 b/tests/qemu-iotests/183
index acdbefa310..d889a3b19c 100755
--- a/tests/qemu-iotests/183
+++ b/tests/qemu-iotests/183
@@ -44,7 +44,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 _supported_os Linux FreeBSD NetBSD
 _supported_fmt qcow2 raw qed quorum
-_supported_proto file
+_supported_proto file fuse
 
 size=64M
 _make_test_img $size
diff --git a/tests/qemu-iotests/186 b/tests/qemu-iotests/186
index 3ea0442d44..0db25b0e68 100755
--- a/tests/qemu-iotests/186
+++ b/tests/qemu-iotests/186
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _require_drivers null-co
 
 if [ "$QEMU_DEFAULT_MACHINE" != "pc" ]; then
diff --git a/tests/qemu-iotests/187 b/tests/qemu-iotests/187
index c6e1dc57a0..f262d83e3a 100755
--- a/tests/qemu-iotests/187
+++ b/tests/qemu-iotests/187
@@ -39,7 +39,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 
 size=64M
 _make_test_img $size
diff --git a/tests/qemu-iotests/191 b/tests/qemu-iotests/191
index d17462e1e4..95a891350d 100755
--- a/tests/qemu-iotests/191
+++ b/tests/qemu-iotests/191
@@ -42,7 +42,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.qemu
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 # An external data file would change the query-named-block-nodes output
 _unsupported_imgopts data_file
 
diff --git a/tests/qemu-iotests/195 b/tests/qemu-iotests/195
index 2351d55fe1..967af5b7b5 100755
--- a/tests/qemu-iotests/195
+++ b/tests/qemu-iotests/195
@@ -38,7 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 
 do_run_qemu()
 {
diff --git a/tests/qemu-iotests/200 b/tests/qemu-iotests/200
index a7aabbd032..046539154f 100755
--- a/tests/qemu-iotests/200
+++ b/tests/qemu-iotests/200
@@ -42,7 +42,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.qemu
 
 _supported_fmt qcow2 qed
-_supported_proto file
+_supported_proto file fuse
 
 BACKING_IMG="$TEST_IMG.base"
 
diff --git a/tests/qemu-iotests/204 b/tests/qemu-iotests/204
index 6770fa9b96..536bb8b534 100755
--- a/tests/qemu-iotests/204
+++ b/tests/qemu-iotests/204
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 # This test assumes that discard leaves zero clusters; see test 177 for
 # other tests that also work in older images
 _unsupported_imgopts 'compat=0.10'
diff --git a/tests/qemu-iotests/214 b/tests/qemu-iotests/214
index af677d90b8..75ae7a14b5 100755
--- a/tests/qemu-iotests/214
+++ b/tests/qemu-iotests/214
@@ -35,7 +35,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 
 # Repairing the corrupted image requires qemu-img check to store a
 # refcount up to 3, which requires at least two refcount bits.
diff --git a/tests/qemu-iotests/217 b/tests/qemu-iotests/217
index d89116ccad..7385342498 100755
--- a/tests/qemu-iotests/217
+++ b/tests/qemu-iotests/217
@@ -36,7 +36,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # This test is specific to qcow2
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 
 # This test needs clusters with at least a refcount of 2 so that
 # OFLAG_COPIED is not set.  refcount_bits=1 is therefore unsupported.
diff --git a/tests/qemu-iotests/220 b/tests/qemu-iotests/220
index a9259b7127..9ba3b3fdcb 100755
--- a/tests/qemu-iotests/220
+++ b/tests/qemu-iotests/220
@@ -35,7 +35,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.pattern
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 # To use a different refcount width but 16 bits we need compat=1.1,
 # and external data files do not support compressed clusters.
diff --git a/tests/qemu-iotests/221 b/tests/qemu-iotests/221
index 0e9096fec7..ca62b3baa1 100755
--- a/tests/qemu-iotests/221
+++ b/tests/qemu-iotests/221
@@ -35,7 +35,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt raw
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 
 _default_cache_mode writeback
diff --git a/tests/qemu-iotests/229 b/tests/qemu-iotests/229
index 5f759fa587..273ac2472d 100755
--- a/tests/qemu-iotests/229
+++ b/tests/qemu-iotests/229
@@ -44,7 +44,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # Needs backing file and backing format support
 _supported_fmt qcow2 qed
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 # blkdebug can only inject errors on bs->file, so external data files
 # do not work with this test
diff --git a/tests/qemu-iotests/247 b/tests/qemu-iotests/247
index 87e37b39e2..6cf2679750 100755
--- a/tests/qemu-iotests/247
+++ b/tests/qemu-iotests/247
@@ -41,7 +41,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # Requires backing files and .bdrv_change_backing_file support
 _supported_fmt qcow2 qed
-_supported_proto file
+_supported_proto file fuse
 
 size=128M
 
diff --git a/tests/qemu-iotests/249 b/tests/qemu-iotests/249
index a9aa9303eb..29453b8c90 100755
--- a/tests/qemu-iotests/249
+++ b/tests/qemu-iotests/249
@@ -42,7 +42,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # Any format implementing BlockDriver.bdrv_change_backing_file
 _supported_fmt qcow2 qed
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 
 IMG_SIZE=1M
diff --git a/tests/qemu-iotests/250 b/tests/qemu-iotests/250
index 9bb6b94d74..3df275c76b 100755
--- a/tests/qemu-iotests/250
+++ b/tests/qemu-iotests/250
@@ -37,7 +37,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 # This test does not make much sense with external data files
 _unsupported_imgopts data_file
diff --git a/tests/qemu-iotests/252 b/tests/qemu-iotests/252
index 6662f4c9de..1d74afff99 100755
--- a/tests/qemu-iotests/252
+++ b/tests/qemu-iotests/252
@@ -42,7 +42,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 # zero cluster support
 _supported_fmt qcow2
 _unsupported_imgopts 'compat=0.10'
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 
 CLUSTER_SIZE=65536
diff --git a/tests/qemu-iotests/265 b/tests/qemu-iotests/265
index 00f2ec769e..0e800fb524 100755
--- a/tests/qemu-iotests/265
+++ b/tests/qemu-iotests/265
@@ -35,7 +35,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # qcow2-specific test
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 
 echo '--- Writing to the image ---'
diff --git a/tests/qemu-iotests/268 b/tests/qemu-iotests/268
index 78c3f4db3a..ddf4312284 100755
--- a/tests/qemu-iotests/268
+++ b/tests/qemu-iotests/268
@@ -38,7 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 
 echo
 echo "== Required alignment larger than cluster size =="
diff --git a/tests/qemu-iotests/272 b/tests/qemu-iotests/272
index c2f782d47b..de475bf6f0 100755
--- a/tests/qemu-iotests/272
+++ b/tests/qemu-iotests/272
@@ -35,7 +35,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # This is a qcow2 regression test
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 
 # External data files do not support compression;
 # We need an exact cluster size (2M) and refcount width (2) so we can
diff --git a/tests/qemu-iotests/273 b/tests/qemu-iotests/273
index 41ffbf39c4..79b4ab4b05 100755
--- a/tests/qemu-iotests/273
+++ b/tests/qemu-iotests/273
@@ -35,7 +35,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # This is a qcow2 regression test
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 # External data files would add nodes to the block graph, so it would
 # not match the reference output
diff --git a/tests/qemu-iotests/279 b/tests/qemu-iotests/279
index 5515d4ed01..2a6315cf17 100755
--- a/tests/qemu-iotests/279
+++ b/tests/qemu-iotests/279
@@ -36,7 +36,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 
 # Backing files are required...
 _supported_fmt qcow qcow2 vmdk qed
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 _unsupported_imgopts "subformat=monolithicFlat" \
                      "subformat=twoGbMaxExtentFlat" \
diff --git a/tests/qemu-iotests/286 b/tests/qemu-iotests/286
index f14445ba4a..f64e0eccea 100755
--- a/tests/qemu-iotests/286
+++ b/tests/qemu-iotests/286
@@ -35,7 +35,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.qemu
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 # Internal snapshots are (currently) impossible with refcount_bits=1,
 # and generally impossible with external data files
 _unsupported_imgopts 'refcount_bits=1[^0-9]' data_file
diff --git a/tests/qemu-iotests/287 b/tests/qemu-iotests/287
index 036cc09e82..3bb383fd4b 100755
--- a/tests/qemu-iotests/287
+++ b/tests/qemu-iotests/287
@@ -32,7 +32,7 @@ status=1	# failure is the default!
 
 # This tests qocw2-specific low-level functionality
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 _unsupported_imgopts 'compat=0.10' data_file
 
diff --git a/tests/qemu-iotests/289 b/tests/qemu-iotests/289
index 1c11d4030e..fe69bde1eb 100755
--- a/tests/qemu-iotests/289
+++ b/tests/qemu-iotests/289
@@ -38,7 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.pattern
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 # This is a v3-exclusive test;
 # As for data_file, error paths often very much depend on whether
 # there is an external data file or not; so we create one exactly when
diff --git a/tests/qemu-iotests/290 b/tests/qemu-iotests/290
index 01ee14dcfb..35c38d4f80 100755
--- a/tests/qemu-iotests/290
+++ b/tests/qemu-iotests/290
@@ -38,7 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 _unsupported_imgopts 'compat=0.10' refcount_bits data_file
 
diff --git a/tests/qemu-iotests/291 b/tests/qemu-iotests/291
index b7320bc7ad..148e8b9ef5 100755
--- a/tests/qemu-iotests/291
+++ b/tests/qemu-iotests/291
@@ -36,7 +36,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.nbd
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 _require_command QEMU_NBD
 # compat=0.10 does not support bitmaps
diff --git a/tests/qemu-iotests/292 b/tests/qemu-iotests/292
index 83ab19231d..3ae2772e3b 100755
--- a/tests/qemu-iotests/292
+++ b/tests/qemu-iotests/292
@@ -38,7 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 # We need qemu-img map to show the file where the data is allocated,
 # but with an external data file, it will show that instead of the
diff --git a/tests/qemu-iotests/293 b/tests/qemu-iotests/293
index f86fe3b413..3363bf07f0 100755
--- a/tests/qemu-iotests/293
+++ b/tests/qemu-iotests/293
@@ -38,7 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2 luks
-_supported_proto file #TODO
+_supported_proto file fuse #TODO
 _require_working_luks
 
 QEMU_IO_OPTIONS=$QEMU_IO_OPTIONS_NO_FMT
diff --git a/tests/qemu-iotests/294 b/tests/qemu-iotests/294
index 9c95ed8c9a..87da35db49 100755
--- a/tests/qemu-iotests/294
+++ b/tests/qemu-iotests/294
@@ -34,7 +34,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt luks
-_supported_proto file #TODO
+_supported_proto file fuse #TODO
 
 QEMU_IO_OPTIONS=$QEMU_IO_OPTIONS_NO_FMT
 
diff --git a/tests/qemu-iotests/305 b/tests/qemu-iotests/305
index 768818af4a..5a415eb2a4 100755
--- a/tests/qemu-iotests/305
+++ b/tests/qemu-iotests/305
@@ -38,7 +38,7 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 . ./common.filter
 
 _supported_fmt qcow2
-_supported_proto file
+_supported_proto file fuse
 _supported_os Linux
 _unsupported_imgopts cluster_size refcount_bits extended_l2 compat=0.10 data_file
 
-- 
2.26.2

[PATCH for-6.0 v3 20/20] iotests/308: Add test for FUSE exports

[Max Reitz]

We have good coverage of the normal I/O paths now, but what remains is a
test that tests some more special cases: Exporting an image on itself
(thus turning a formatted image into a raw one), some error cases, and
non-writable and non-growable exports.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
---
 tests/qemu-iotests/308     | 339 +++++++++++++++++++++++++++++++++++++
 tests/qemu-iotests/308.out |  97 +++++++++++
 tests/qemu-iotests/group   |   1 +
 3 files changed, 437 insertions(+)
 create mode 100755 tests/qemu-iotests/308
 create mode 100644 tests/qemu-iotests/308.out

diff --git a/tests/qemu-iotests/308 b/tests/qemu-iotests/308
new file mode 100755
index 0000000000..b30f4400f6
--- /dev/null
+++ b/tests/qemu-iotests/308
@@ -0,0 +1,339 @@
+#!/usr/bin/env bash
+#
+# Test FUSE exports (in ways that are not captured by the generic
+# tests)
+#
+# Copyright (C) 2020 Red Hat, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+seq=$(basename "$0")
+echo "QA output created by $seq"
+
+status=1	# failure is the default!
+
+_cleanup()
+{
+    _cleanup_qemu
+    _cleanup_test_img
+    rmdir "$EXT_MP" 2>/dev/null
+    rm -f "$EXT_MP"
+    rm -f "$COPIED_IMG"
+}
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+# get standard environment, filters and checks
+. ./common.rc
+. ./common.filter
+. ./common.qemu
+
+# Generic format, but needs a plain filename
+_supported_fmt generic
+if [ "$IMGOPTSSYNTAX" = "true" ]; then
+    _unsupported_fmt $IMGFMT
+fi
+# We need the image to have exactly the specified size, and VPC does
+# not allow that by default
+_unsupported_fmt vpc
+
+_supported_proto file # We create the FUSE export manually
+_supported_os Linux # We need /dev/urandom
+
+# $1: Export ID
+# $2: Options (beyond the node-name and ID)
+# $3: Expected return value (defaults to 'return')
+# $4: Node to export (defaults to 'node-format')
+fuse_export_add()
+{
+    _send_qemu_cmd $QEMU_HANDLE \
+        "{'execute': 'block-export-add',
+          'arguments': {
+              'type': 'fuse',
+              'id': '$1',
+              'node-name': '${4:-node-format}',
+              $2
+          } }" \
+        "${3:-return}" \
+        | _filter_imgfmt
+}
+
+# $1: Export ID
+fuse_export_del()
+{
+    _send_qemu_cmd $QEMU_HANDLE \
+        "{'execute': 'block-export-del',
+          'arguments': {
+              'id': '$1'
+          } }" \
+        'return'
+
+    _send_qemu_cmd $QEMU_HANDLE \
+        '' \
+        'BLOCK_EXPORT_DELETED'
+}
+
+# Return the length of the protocol file
+# $1: Protocol node export mount point
+# $2: Original file (to compare)
+get_proto_len()
+{
+    len1=$(stat -c '%s' "$1")
+    len2=$(stat -c '%s' "$2")
+
+    if [ "$len1" != "$len2" ]; then
+        echo 'ERROR: Length of export and original differ:' >&2
+        echo "$len1 != $len2" >&2
+    else
+        echo '(OK: Lengths of export and original are the same)' >&2
+    fi
+
+    echo "$len1"
+}
+
+COPIED_IMG="$TEST_IMG.copy"
+EXT_MP="$TEST_IMG.fuse"
+
+echo '=== Set up ==='
+
+# Create image with random data
+_make_test_img 64M
+$QEMU_IO -c 'write -s /dev/urandom 0 64M' "$TEST_IMG" | _filter_qemu_io
+
+_launch_qemu
+_send_qemu_cmd $QEMU_HANDLE \
+    "{'execute': 'qmp_capabilities'}" \
+    'return'
+
+# Separate blockdev-add calls for format and protocol so we can remove
+# the format layer later on
+_send_qemu_cmd $QEMU_HANDLE \
+    "{'execute': 'blockdev-add',
+      'arguments': {
+          'driver': 'file',
+          'node-name': 'node-protocol',
+          'filename': '$TEST_IMG'
+      } }" \
+    'return'
+
+_send_qemu_cmd $QEMU_HANDLE \
+    "{'execute': 'blockdev-add',
+      'arguments': {
+          'driver': '$IMGFMT',
+          'node-name': 'node-format',
+          'file': 'node-protocol'
+      } }" \
+    'return'
+
+echo
+echo '=== Mountpoint not present ==='
+
+rmdir "$EXT_MP" 2>/dev/null
+rm -f "$EXT_MP"
+output=$(fuse_export_add 'export-err' "'mountpoint': '$EXT_MP'" error)
+
+if echo "$output" | grep -q "Invalid parameter 'fuse'"; then
+    _notrun 'No FUSE support'
+fi
+
+echo "$output"
+
+echo
+echo '=== Mountpoint is a directory ==='
+
+mkdir "$EXT_MP"
+fuse_export_add 'export-err' "'mountpoint': '$EXT_MP'" error
+rmdir "$EXT_MP"
+
+echo
+echo '=== Mountpoint is a regular file ==='
+
+touch "$EXT_MP"
+fuse_export_add 'export-mp' "'mountpoint': '$EXT_MP'"
+
+# Check that the export presents the same data as the original image
+$QEMU_IMG compare -f raw -F $IMGFMT -U "$EXT_MP" "$TEST_IMG"
+
+echo
+echo '=== Mount over existing file ==='
+
+# This is the coolest feature of FUSE exports: You can transparently
+# make images in any format appear as raw images
+fuse_export_add 'export-img' "'mountpoint': '$TEST_IMG'"
+
+# Accesses both exports at the same time, so we get a concurrency test
+$QEMU_IMG compare -f raw -F raw -U "$EXT_MP" "$TEST_IMG"
+
+# Just to be sure, we later want to compare the data offline.  Also,
+# this allows us to see that cp works without complaining.
+# (This is not a given, because cp will expect a short read at EOF.
+# Internally, qemu does not allow short reads, so we have to check
+# whether the FUSE export driver lets them work.)
+cp "$TEST_IMG" "$COPIED_IMG"
+
+# $TEST_IMG will be in mode 0400 because it is read-only; we are going
+# to write to the copy, so make it writable
+chmod 0600 "$COPIED_IMG"
+
+echo
+echo '=== Double export ==='
+
+# We have already seen that exporting a node twice works fine, but you
+# cannot export anything twice on the same mount point.  The reason is
+# that qemu has to stat the given mount point, and this would have to
+# be answered by the same qemu instance if it already has an export
+# there.  However, it cannot answer the stat because it is itself
+# caught up in that same stat.
+fuse_export_add 'export-err' "'mountpoint': '$EXT_MP'" error
+
+echo
+echo '=== Remove export ==='
+
+# Double-check that $EXT_MP appears as a non-empty file (the raw image)
+$QEMU_IMG info -f raw "$EXT_MP" | grep 'virtual size'
+
+fuse_export_del 'export-mp'
+
+# See that the file appears empty again
+$QEMU_IMG info -f raw "$EXT_MP" | grep 'virtual size'
+
+echo
+echo '=== Writable export ==='
+
+fuse_export_add 'export-mp' "'mountpoint': '$EXT_MP', 'writable': true"
+
+# Check that writing to the read-only export fails
+$QEMU_IO -f raw -c 'write -P 42 1M 64k' "$TEST_IMG" | _filter_qemu_io
+
+# But here it should work
+$QEMU_IO -f raw -c 'write -P 42 1M 64k' "$EXT_MP" | _filter_qemu_io
+
+# (Adjust the copy, too)
+$QEMU_IO -f raw -c 'write -P 42 1M 64k' "$COPIED_IMG" | _filter_qemu_io
+
+echo
+echo '=== Resizing exports ==='
+
+# Here, we need to export the protocol node -- the format layer may
+# not be growable, simply because the format does not support it.
+
+# Remove all exports and the format node first so permissions will not
+# get in the way
+fuse_export_del 'export-mp'
+fuse_export_del 'export-img'
+
+_send_qemu_cmd $QEMU_HANDLE \
+    "{'execute': 'blockdev-del',
+      'arguments': {
+          'node-name': 'node-format'
+      } }" \
+    'return'
+
+# Now export the protocol node
+fuse_export_add \
+    'export-mp' \
+    "'mountpoint': '$EXT_MP', 'writable': true" \
+    'return' \
+    'node-protocol'
+
+echo
+echo '--- Try growing non-growable export ---'
+
+# Get the current size so we can write beyond the EOF
+orig_len=$(get_proto_len "$EXT_MP" "$TEST_IMG")
+orig_disk_usage=$(stat -c '%b' "$TEST_IMG")
+
+# Should fail (exports are non-growable by default)
+# (Note that qemu-io can never write beyond the EOF, so we have to use
+# dd here)
+dd if=/dev/zero of="$EXT_MP" bs=1 count=64k seek=$orig_len 2>&1 \
+    | _filter_testdir | _filter_imgfmt
+
+echo
+echo '--- Resize export ---'
+
+# But we can truncate it explicitly; even with fallocate
+fallocate -o "$orig_len" -l 64k "$EXT_MP"
+
+new_len=$(get_proto_len "$EXT_MP" "$TEST_IMG")
+if [ "$new_len" != "$((orig_len + 65536))" ]; then
+    echo 'ERROR: Unexpected post-truncate image size:'
+    echo "$new_len != $((orig_len + 65536))"
+else
+    echo 'OK: Post-truncate image size is as expected'
+fi
+
+new_disk_usage=$(stat -c '%b' "$TEST_IMG")
+if [ "$new_disk_usage" -gt "$orig_disk_usage" ]; then
+    echo 'OK: Disk usage grew with fallocate'
+else
+    echo 'ERROR: Disk usage did not grow despite fallocate:'
+    echo "$orig_disk_usage => $new_disk_usage"
+fi
+
+echo
+echo '--- Try growing growable export ---'
+
+# Now export as growable
+fuse_export_del 'export-mp'
+fuse_export_add \
+    'export-mp' \
+    "'mountpoint': '$EXT_MP', 'writable': true, 'growable': true" \
+    'return' \
+    'node-protocol'
+
+# Now we should be able to write beyond the EOF
+dd if=/dev/zero of="$EXT_MP" bs=1 count=64k seek=$new_len 2>&1 \
+    | _filter_testdir | _filter_imgfmt
+
+new_len=$(get_proto_len "$EXT_MP" "$TEST_IMG")
+if [ "$new_len" != "$((orig_len + 131072))" ]; then
+    echo 'ERROR: Unexpected post-grow image size:'
+    echo "$new_len != $((orig_len + 131072))"
+else
+    echo 'OK: Post-grow image size is as expected'
+fi
+
+echo
+echo '--- Shrink export ---'
+
+# Now go back to the original size
+truncate -s "$orig_len" "$EXT_MP"
+
+new_len=$(get_proto_len "$EXT_MP" "$TEST_IMG")
+if [ "$new_len" != "$orig_len" ]; then
+    echo 'ERROR: Unexpected post-truncate image size:'
+    echo "$new_len != $orig_len"
+else
+    echo 'OK: Post-truncate image size is as expected'
+fi
+
+echo
+echo '=== Tear down ==='
+
+_send_qemu_cmd $QEMU_HANDLE \
+    "{'execute': 'quit'}" \
+    'return'
+
+wait=yes _cleanup_qemu
+
+echo
+echo '=== Compare copy with original ==='
+
+$QEMU_IMG compare -f raw -F $IMGFMT "$COPIED_IMG" "$TEST_IMG"
+
+# success, all done
+echo "*** done"
+rm -f $seq.full
+status=0
diff --git a/tests/qemu-iotests/308.out b/tests/qemu-iotests/308.out
new file mode 100644
index 0000000000..b93aceed2e
--- /dev/null
+++ b/tests/qemu-iotests/308.out
@@ -0,0 +1,97 @@
+QA output created by 308
+=== Set up ===
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864
+wrote 67108864/67108864 bytes at offset 0
+64 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+{'execute': 'qmp_capabilities'}
+{"return": {}}
+{'execute': 'blockdev-add', 'arguments': { 'driver': 'file', 'node-name': 'node-protocol', 'filename': 'TEST_DIR/t.IMGFMT' } }
+{"return": {}}
+{'execute': 'blockdev-add', 'arguments': { 'driver': 'IMGFMT', 'node-name': 'node-format', 'file': 'node-protocol' } }
+{"return": {}}
+
+=== Mountpoint not present ===
+{'execute': 'block-export-add', 'arguments': { 'type': 'fuse', 'id': 'export-err', 'node-name': 'node-format', 'mountpoint': 'TEST_DIR/t.IMGFMT.fuse' } }
+{"error": {"class": "GenericError", "desc": "Failed to stat 'TEST_DIR/t.IMGFMT.fuse': No such file or directory"}}
+
+=== Mountpoint is a directory ===
+{'execute': 'block-export-add', 'arguments': { 'type': 'fuse', 'id': 'export-err', 'node-name': 'node-format', 'mountpoint': 'TEST_DIR/t.IMGFMT.fuse' } }
+{"error": {"class": "GenericError", "desc": "'TEST_DIR/t.IMGFMT.fuse' is not a regular file"}}
+
+=== Mountpoint is a regular file ===
+{'execute': 'block-export-add', 'arguments': { 'type': 'fuse', 'id': 'export-mp', 'node-name': 'node-format', 'mountpoint': 'TEST_DIR/t.IMGFMT.fuse' } }
+{"return": {}}
+Images are identical.
+
+=== Mount over existing file ===
+{'execute': 'block-export-add', 'arguments': { 'type': 'fuse', 'id': 'export-img', 'node-name': 'node-format', 'mountpoint': 'TEST_DIR/t.IMGFMT' } }
+{"return": {}}
+Images are identical.
+
+=== Double export ===
+{'execute': 'block-export-add', 'arguments': { 'type': 'fuse', 'id': 'export-err', 'node-name': 'node-format', 'mountpoint': 'TEST_DIR/t.IMGFMT.fuse' } }
+{"error": {"class": "GenericError", "desc": "There already is a FUSE export on 'TEST_DIR/t.IMGFMT.fuse'"}}
+
+=== Remove export ===
+virtual size: 64 MiB (67108864 bytes)
+{'execute': 'block-export-del', 'arguments': { 'id': 'export-mp' } }
+{"return": {}}
+{"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "BLOCK_EXPORT_DELETED", "data": {"id": "export-mp"}}
+virtual size: 0 B (0 bytes)
+
+=== Writable export ===
+{'execute': 'block-export-add', 'arguments': { 'type': 'fuse', 'id': 'export-mp', 'node-name': 'node-format', 'mountpoint': 'TEST_DIR/t.IMGFMT.fuse', 'writable': true } }
+{"return": {}}
+write failed: Permission denied
+wrote 65536/65536 bytes at offset 1048576
+64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 65536/65536 bytes at offset 1048576
+64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
+=== Resizing exports ===
+{'execute': 'block-export-del', 'arguments': { 'id': 'export-mp' } }
+{"return": {}}
+{"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "BLOCK_EXPORT_DELETED", "data": {"id": "export-mp"}}
+{'execute': 'block-export-del', 'arguments': { 'id': 'export-img' } }
+{"return": {}}
+{"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "BLOCK_EXPORT_DELETED", "data": {"id": "export-img"}}
+{'execute': 'blockdev-del', 'arguments': { 'node-name': 'node-format' } }
+{"return": {}}
+{'execute': 'block-export-add', 'arguments': { 'type': 'fuse', 'id': 'export-mp', 'node-name': 'node-protocol', 'mountpoint': 'TEST_DIR/t.IMGFMT.fuse', 'writable': true } }
+{"return": {}}
+
+--- Try growing non-growable export ---
+(OK: Lengths of export and original are the same)
+dd: error writing 'TEST_DIR/t.IMGFMT.fuse': Input/output error
+1+0 records in
+0+0 records out
+
+--- Resize export ---
+(OK: Lengths of export and original are the same)
+OK: Post-truncate image size is as expected
+OK: Disk usage grew with fallocate
+
+--- Try growing growable export ---
+{'execute': 'block-export-del', 'arguments': { 'id': 'export-mp' } }
+{"return": {}}
+{"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "BLOCK_EXPORT_DELETED", "data": {"id": "export-mp"}}
+{'execute': 'block-export-add', 'arguments': { 'type': 'fuse', 'id': 'export-mp', 'node-name': 'node-protocol', 'mountpoint': 'TEST_DIR/t.IMGFMT.fuse', 'writable': true, 'growable': true } }
+{"return": {}}
+65536+0 records in
+65536+0 records out
+(OK: Lengths of export and original are the same)
+OK: Post-grow image size is as expected
+
+--- Shrink export ---
+(OK: Lengths of export and original are the same)
+OK: Post-truncate image size is as expected
+
+=== Tear down ===
+{'execute': 'quit'}
+{"return": {}}
+{"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "SHUTDOWN", "data": {"guest": false, "reason": "host-qmp-quit"}}
+{"timestamp": {"seconds":  TIMESTAMP, "microseconds":  TIMESTAMP}, "event": "BLOCK_EXPORT_DELETED", "data": {"id": "export-mp"}}
+
+=== Compare copy with original ===
+Images are identical.
+*** done
diff --git a/tests/qemu-iotests/group b/tests/qemu-iotests/group
index 3432989283..77e105c4d0 100644
--- a/tests/qemu-iotests/group
+++ b/tests/qemu-iotests/group
@@ -315,3 +315,4 @@
 304 rw quick
 305 rw quick
 307 rw quick export
+308 rw
-- 
2.26.2

Re: [PATCH for-6.0 v3 00/20] block/export: Allow exporting BDSs via FUSE

[Kevin Wolf]

Am 27.10.2020 um 20:05 hat Max Reitz geschrieben:
> v1: https://lists.nongnu.org/archive/html/qemu-block/2019-12/msg00451.html
> v2: https://lists.nongnu.org/archive/html/qemu-block/2020-09/msg01611.html
> 
> Branch: https://github.com/XanClic/qemu.git fuse-exports-v3
> Branch: https://git.xanclic.moe/XanClic/qemu.git fuse-exports-v3
> 
> 
> Hi,
> 
> Ever since I found out that you can mount FUSE filesystems on regular
> files (not just directories), I had the idea of adding FUSE block
> exports to qemu where you can export block nodes as raw images.  The
> best thing is that you’d be able to mount an image on itself, so
> whatever format it may be in, qemu lets it appear as a raw image (and
> you can then use regular tools like dd on it).
> 
> The performance is quite bad so far, but we can always try to improve it
> if the need arises.  For now I consider it mostly a cute feature to get
> easy access to the raw contents of image files in any format (without
> requiring root rights).
> 
> 
> This series does the following:
> 
> First, add the FUSE export module (block/export/fuse.c) that implements
> the basic file access functions.  (Note that you need libfuse 3.8.0 or
> later for SEEK_HOLE/SEEK_DATA.)
> 
> Second, it allows using FUSE exports as a protocol in the iotests and
> makes many iotests work with it.  (The file node is exported by a
> background qemu instance to $SOCK_DIR.)
> 
> This gives us a lot of coverage for, well, not free (it does take twelve
> patches), but for cheap; but there are still some more specialized
> things we want to test, so third and last, this series adds an iotest
> dedicated to FUSE exports.

Thanks, applied to the block branch.

Kevin