[PULL 0/3] Block patches

[PULL 0/3] Block patches

[Stefan Hajnoczi]

The following changes since commit 7208429223963c405c62fa2611398f1aa8033593:

  Merge tag 'mem-2022-10-28' of https://github.com/davidhildenbrand/qemu into staging (2022-10-30 18:31:59 -0400)

are available in the Git repository at:

  https://gitlab.com/stefanha/qemu.git tags/block-pull-request

for you to fetch changes up to 6c32fc0df9cd901add75618c831fb26a9eb742cb:

  block/blkio: Make driver nvme-io_uring take a "path" instead of a "filename" (2022-10-31 14:35:14 -0400)

----------------------------------------------------------------
Pull request

Note that we're still discussing "block/blkio: Make driver nvme-io_uring take a
"path" instead of a "filename"". I have sent the pull request now so everything
is ready for the soft freeze tomorrow if we decide to go ahead with the patch.

----------------------------------------------------------------

Alberto Faria (3):
  block/blkio: Add virtio-blk-vfio-pci BlockDriver
  block/blkio: Tolerate device size changes
  block/blkio: Make driver nvme-io_uring take a "path" instead of a
    "filename"

 qapi/block-core.json | 22 +++++++++++++++++++--
 block/blkio.c        | 47 ++++++++++++++++++++++++++++++++++++++++----
 2 files changed, 63 insertions(+), 6 deletions(-)

-- 
2.38.1

[PULL 1/3] block/blkio: Add virtio-blk-vfio-pci BlockDriver

[Stefan Hajnoczi]

From: Alberto Faria <afaria@redhat.com>

libblkio 1.1.0 [1] introduces a virtio-blk-vfio-pci driver, which
accesses a virtio-blk PCI device using VFIO. Add a corresponding
BlockDriver.

[1] https://gitlab.com/libblkio/libblkio/-/tree/v1.1.0

Signed-off-by: Alberto Faria <afaria@redhat.com>
Message-id: 20221028131635.710267-1-afaria@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 qapi/block-core.json | 18 ++++++++++++++++++
 block/blkio.c        |  8 ++++++++
 2 files changed, 26 insertions(+)

diff --git a/qapi/block-core.json b/qapi/block-core.json
index cb5079e645..81bbb0b893 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -2960,6 +2960,7 @@
             'raw', 'rbd',
             { 'name': 'replication', 'if': 'CONFIG_REPLICATION' },
             'ssh', 'throttle', 'vdi', 'vhdx',
+            { 'name': 'virtio-blk-vfio-pci', 'if': 'CONFIG_BLKIO' },
             { 'name': 'virtio-blk-vhost-user', 'if': 'CONFIG_BLKIO' },
             { 'name': 'virtio-blk-vhost-vdpa', 'if': 'CONFIG_BLKIO' },
             'vmdk', 'vpc', 'vvfat' ] }
@@ -3711,6 +3712,20 @@
   'data': { 'filename': 'str' },
   'if': 'CONFIG_BLKIO' }
 
+##
+# @BlockdevOptionsVirtioBlkVfioPci:
+#
+# Driver specific block device options for the virtio-blk-vfio-pci backend.
+#
+# @path: path to the PCI device's sysfs directory (e.g.
+#        /sys/bus/pci/devices/0000:00:01.0).
+#
+# Since: 7.2
+##
+{ 'struct': 'BlockdevOptionsVirtioBlkVfioPci',
+  'data': { 'path': 'str' },
+  'if': 'CONFIG_BLKIO' }
+
 ##
 # @BlockdevOptionsVirtioBlkVhostUser:
 #
@@ -4390,6 +4405,9 @@
       'throttle':   'BlockdevOptionsThrottle',
       'vdi':        'BlockdevOptionsGenericFormat',
       'vhdx':       'BlockdevOptionsGenericFormat',
+      'virtio-blk-vfio-pci':
+                    { 'type': 'BlockdevOptionsVirtioBlkVfioPci',
+                      'if': 'CONFIG_BLKIO' },
       'virtio-blk-vhost-user':
                     { 'type': 'BlockdevOptionsVirtioBlkVhostUser',
                       'if': 'CONFIG_BLKIO' },
diff --git a/block/blkio.c b/block/blkio.c
index 82f26eedd2..f55eb774b4 100644
--- a/block/blkio.c
+++ b/block/blkio.c
@@ -25,6 +25,7 @@
  */
 #define DRIVER_IO_URING "io_uring"
 #define DRIVER_NVME_IO_URING "nvme-io_uring"
+#define DRIVER_VIRTIO_BLK_VFIO_PCI "virtio-blk-vfio-pci"
 #define DRIVER_VIRTIO_BLK_VHOST_USER "virtio-blk-vhost-user"
 #define DRIVER_VIRTIO_BLK_VHOST_VDPA "virtio-blk-vhost-vdpa"
 
@@ -704,6 +705,8 @@ static int blkio_file_open(BlockDriverState *bs, QDict *options, int flags,
         ret = blkio_io_uring_open(bs, options, flags, errp);
     } else if (strcmp(blkio_driver, DRIVER_NVME_IO_URING) == 0) {
         ret = blkio_nvme_io_uring(bs, options, flags, errp);
+    } else if (strcmp(blkio_driver, DRIVER_VIRTIO_BLK_VFIO_PCI) == 0) {
+        ret = blkio_virtio_blk_common_open(bs, options, flags, errp);
     } else if (strcmp(blkio_driver, DRIVER_VIRTIO_BLK_VHOST_USER) == 0) {
         ret = blkio_virtio_blk_common_open(bs, options, flags, errp);
     } else if (strcmp(blkio_driver, DRIVER_VIRTIO_BLK_VHOST_VDPA) == 0) {
@@ -989,6 +992,10 @@ static BlockDriver bdrv_nvme_io_uring = BLKIO_DRIVER(
     .bdrv_needs_filename = true,
 );
 
+static BlockDriver bdrv_virtio_blk_vfio_pci = BLKIO_DRIVER(
+    DRIVER_VIRTIO_BLK_VFIO_PCI
+);
+
 static BlockDriver bdrv_virtio_blk_vhost_user = BLKIO_DRIVER(
     DRIVER_VIRTIO_BLK_VHOST_USER
 );
@@ -1001,6 +1008,7 @@ static void bdrv_blkio_init(void)
 {
     bdrv_register(&bdrv_io_uring);
     bdrv_register(&bdrv_nvme_io_uring);
+    bdrv_register(&bdrv_virtio_blk_vfio_pci);
     bdrv_register(&bdrv_virtio_blk_vhost_user);
     bdrv_register(&bdrv_virtio_blk_vhost_vdpa);
 }
-- 
2.38.1

[PULL 2/3] block/blkio: Tolerate device size changes

[Stefan Hajnoczi]

From: Alberto Faria <afaria@redhat.com>

Some libblkio drivers may be able to work with regular files (e.g.,
io_uring) or otherwise resizable devices. Conservatively set
BlockDriver::has_variable_length to true to ensure bdrv_nb_sectors()
always gives up-to-date results.

Also implement BlockDriver::bdrv_co_truncate for the case where no
preallocation is needed and the device already has a size compatible
with what was requested.

Signed-off-by: Alberto Faria <afaria@redhat.com>
Message-id: 20221029122031.975273-1-afaria@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 block/blkio.c | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/block/blkio.c b/block/blkio.c
index f55eb774b4..d850506acd 100644
--- a/block/blkio.c
+++ b/block/blkio.c
@@ -848,6 +848,31 @@ static int64_t blkio_getlength(BlockDriverState *bs)
     return capacity;
 }
 
+static int coroutine_fn blkio_truncate(BlockDriverState *bs, int64_t offset,
+                                       bool exact, PreallocMode prealloc,
+                                       BdrvRequestFlags flags, Error **errp)
+{
+    int64_t current_length;
+
+    if (prealloc != PREALLOC_MODE_OFF) {
+        error_setg(errp, "Unsupported preallocation mode '%s'",
+                   PreallocMode_str(prealloc));
+        return -ENOTSUP;
+    }
+
+    current_length = blkio_getlength(bs);
+
+    if (offset > current_length) {
+        error_setg(errp, "Cannot grow device");
+        return -EINVAL;
+    } else if (exact && offset != current_length) {
+        error_setg(errp, "Cannot resize device");
+        return -ENOTSUP;
+    }
+
+    return 0;
+}
+
 static int blkio_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
 {
     return 0;
@@ -963,10 +988,12 @@ static void blkio_refresh_limits(BlockDriverState *bs, Error **errp)
     { \
         .format_name             = name, \
         .protocol_name           = name, \
+        .has_variable_length     = true, \
         .instance_size           = sizeof(BDRVBlkioState), \
         .bdrv_file_open          = blkio_file_open, \
         .bdrv_close              = blkio_close, \
         .bdrv_getlength          = blkio_getlength, \
+        .bdrv_co_truncate        = blkio_truncate, \
         .bdrv_get_info           = blkio_get_info, \
         .bdrv_attach_aio_context = blkio_attach_aio_context, \
         .bdrv_detach_aio_context = blkio_detach_aio_context, \
-- 
2.38.1

[PULL 3/3] block/blkio: Make driver nvme-io_uring take a "path" instead of a "filename"

[Stefan Hajnoczi]

From: Alberto Faria <afaria@redhat.com>

The nvme-io_uring driver expects a character special file such as
/dev/ng0n1. Follow the convention of having a "filename" option when a
regular file is expected, and a "path" option otherwise.

This makes io_uring the only libblkio-based driver with a "filename"
option, as it accepts a regular file (even though it can also take a
block special file).

Signed-off-by: Alberto Faria <afaria@redhat.com>
Message-id: 20221028233854.839933-1-afaria@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 qapi/block-core.json |  4 ++--
 block/blkio.c        | 12 ++++++++----
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/qapi/block-core.json b/qapi/block-core.json
index 81bbb0b893..6d904004f8 100644
--- a/qapi/block-core.json
+++ b/qapi/block-core.json
@@ -3704,12 +3704,12 @@
 #
 # Driver specific block device options for the nvme-io_uring backend.
 #
-# @filename: path to the image file
+# @path: path to the image file
 #
 # Since: 7.2
 ##
 { 'struct': 'BlockdevOptionsNvmeIoUring',
-  'data': { 'filename': 'str' },
+  'data': { 'path': 'str' },
   'if': 'CONFIG_BLKIO' }
 
 ##
diff --git a/block/blkio.c b/block/blkio.c
index d850506acd..620fab28a7 100644
--- a/block/blkio.c
+++ b/block/blkio.c
@@ -640,12 +640,17 @@ static int blkio_io_uring_open(BlockDriverState *bs, QDict *options, int flags,
 static int blkio_nvme_io_uring(BlockDriverState *bs, QDict *options, int flags,
                                Error **errp)
 {
-    const char *filename = qdict_get_str(options, "filename");
+    const char *path = qdict_get_try_str(options, "path");
     BDRVBlkioState *s = bs->opaque;
     int ret;
 
-    ret = blkio_set_str(s->blkio, "path", filename);
-    qdict_del(options, "filename");
+    if (!path) {
+        error_setg(errp, "missing 'path' option");
+        return -EINVAL;
+    }
+
+    ret = blkio_set_str(s->blkio, "path", path);
+    qdict_del(options, "path");
     if (ret < 0) {
         error_setg_errno(errp, -ret, "failed to set path: %s",
                          blkio_get_error_msg());
@@ -1016,7 +1021,6 @@ static BlockDriver bdrv_io_uring = BLKIO_DRIVER(
 
 static BlockDriver bdrv_nvme_io_uring = BLKIO_DRIVER(
     DRIVER_NVME_IO_URING,
-    .bdrv_needs_filename = true,
 );
 
 static BlockDriver bdrv_virtio_blk_vfio_pci = BLKIO_DRIVER(
-- 
2.38.1

Re: [PULL 0/3] Block patches

[Stefan Hajnoczi]

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Applied, thanks.

Please update the changelog at https://wiki.qemu.org/ChangeLog/7.2 for any user-visible changes.

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