[PATCH v3 4/4] blockdev: Drop deprecated bogus -drive interface type

[Markus Armbruster]

Daniel P. Berrangé <berrange at redhat.com> writes:

> On Tue, Mar 09, 2021 at 05:12:13PM +0100, Markus Armbruster wrote:
>> Drop the crap deprecated in commit a1b40bda08 "blockdev: Deprecate
>> -drive with bogus interface type" (v5.1.0).
>> 
>> Signed-off-by: Markus Armbruster <armbru at redhat.com>
>> ---
>>  docs/system/deprecated.rst       |  7 ------
>>  docs/system/removed-features.rst |  7 ++++++
>>  include/sysemu/blockdev.h        |  1 -
>>  blockdev.c                       | 37 +++++++++++++-------------------
>>  softmmu/vl.c                     |  8 +------
>>  5 files changed, 23 insertions(+), 37 deletions(-)
>> 
>> diff --git a/docs/system/deprecated.rst b/docs/system/deprecated.rst
>> index 601e9647a5..664ed60e9f 100644
>> --- a/docs/system/deprecated.rst
>> +++ b/docs/system/deprecated.rst
>> @@ -94,13 +94,6 @@ QEMU 5.1 has three options:
>>        to the user to load all the images they need.
>>   3. ``-bios <file>`` - Tells QEMU to load the specified file as the firmwrae.
>>  
>> -``-drive`` with bogus interface type (since 5.1)
>> -''''''''''''''''''''''''''''''''''''''''''''''''
>> -
>> -Drives with interface types other than ``if=none`` are for onboard
>> -devices.  It is possible to use drives the board doesn't pick up with
>> --device.  This usage is now deprecated.  Use ``if=none`` instead.
>> -
>>  Short-form boolean options (since 6.0)
>>  ''''''''''''''''''''''''''''''''''''''
>>  
>> diff --git a/docs/system/removed-features.rst b/docs/system/removed-features.rst
>> index 77e7ba1339..e6d2fbe798 100644
>> --- a/docs/system/removed-features.rst
>> +++ b/docs/system/removed-features.rst
>> @@ -87,6 +87,13 @@ becomes
>>      -device isa-fdc,...
>>      -device floppy,unit=1,drive=...
>>  
>> +``-drive`` with bogus interface type (removed in 6.0)
>> +'''''''''''''''''''''''''''''''''''''''''''''''''''''
>> +
>> +Drives with interface types other than ``if=none`` are for onboard
>> +devices.  Drives the board doesn't pick up can no longer be used with
>> +-device.  Use ``if=none`` instead.
>> +
>>  QEMU Machine Protocol (QMP) commands
>>  ------------------------------------
>>  
>> diff --git a/include/sysemu/blockdev.h b/include/sysemu/blockdev.h
>> index 3b5fcda08d..32c2d6023c 100644
>> --- a/include/sysemu/blockdev.h
>> +++ b/include/sysemu/blockdev.h
>> @@ -35,7 +35,6 @@ struct DriveInfo {
>>      bool is_default;            /* Added by default_drive() ?  */
>>      int media_cd;
>>      QemuOpts *opts;
>> -    bool claimed_by_board;
>>      QTAILQ_ENTRY(DriveInfo) next;
>>  };
>>  
>> diff --git a/blockdev.c b/blockdev.c
>> index cd438e60e3..2e01889cff 100644
>> --- a/blockdev.c
>> +++ b/blockdev.c
>> @@ -240,19 +240,10 @@ DriveInfo *drive_get(BlockInterfaceType type, int bus, int unit)
>>      return NULL;
>>  }
>>  
>> -void drive_mark_claimed_by_board(void)
>> -{
>> -    BlockBackend *blk;
>> -    DriveInfo *dinfo;
>> -
>> -    for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
>> -        dinfo = blk_legacy_dinfo(blk);
>> -        if (dinfo && blk_get_attached_dev(blk)) {
>> -            dinfo->claimed_by_board = true;
>> -        }
>> -    }
>> -}
>> -
>> +/*
>> + * Check board claimed all -drive that are meant to be claimed.
>> + * Fatal error if any remain unclaimed.
>> + */
>>  void drive_check_orphaned(void)
>>  {
>>      BlockBackend *blk;
>> @@ -262,7 +253,17 @@ void drive_check_orphaned(void)
>>  
>>      for (blk = blk_next(NULL); blk; blk = blk_next(blk)) {
>>          dinfo = blk_legacy_dinfo(blk);
>> -        if (dinfo->is_default || dinfo->type == IF_NONE) {
>> +        /*
>> +         * Ignore default drives, because we create certain default
>> +         * drives unconditionally, then leave them unclaimed.  Not the
>> +         * users fault.
>> +         * Ignore IF_VIRTIO, because it gets desugared into -device,
>> +         * so we can leave failing to -device.
>> +         * Ignore IF_NONE, because leaving unclaimed IF_NONE remains
>> +         * available for device_add is a feature.
>> +         */
>> +        if (dinfo->is_default || dinfo->type == IF_VIRTIO
>> +            || dinfo->type == IF_NONE) {
>>              continue;
>>          }
>>          if (!blk_get_attached_dev(blk)) {
>> @@ -273,14 +274,6 @@ void drive_check_orphaned(void)
>>                           if_name[dinfo->type], dinfo->bus, dinfo->unit);
>>              loc_pop(&loc);
>>              orphans = true;
>> -            continue;
>> -        }
>> -        if (!dinfo->claimed_by_board && dinfo->type != IF_VIRTIO) {
>> -            loc_push_none(&loc);
>> -            qemu_opts_loc_restore(dinfo->opts);
>> -            warn_report("bogus if=%s is deprecated, use if=none",
>> -                        if_name[dinfo->type]);
>> -            loc_pop(&loc);
>>          }
>>      }
>>  
>> diff --git a/softmmu/vl.c b/softmmu/vl.c
>> index ff488ea3e7..7453611152 100644
>> --- a/softmmu/vl.c
>> +++ b/softmmu/vl.c
>> @@ -2460,13 +2460,7 @@ static void qemu_init_board(void)
>>      /* From here on we enter MACHINE_PHASE_INITIALIZED.  */
>>      machine_run_board_init(current_machine);
>>  
>> -    /*
>> -     * TODO To drop support for deprecated bogus if=..., move
>> -     * drive_check_orphaned() here, replacing this call.  Also drop
>> -     * its deprecation warning, along with DriveInfo member
>> -     * @claimed_by_board.
>> -     */
>> -    drive_mark_claimed_by_board();
>> +    drive_check_orphaned();
>
> This method is already called by qemu_machine_creation_done(), which is
> invoked shortly after this qemu_init_board() is run.
>
> So either this added instance, or the later call to drive_check_orphaned
> feels redundant

You're right.

I'll drop the one in qemu_machine_creation_done().  Rationale:

* Before the patch, we reject -drive if=T when T != none and nothing
  claimed it.  We warn unless the board claimed it.  "Nothing claimed
  it" is known only after qemu_create_cli_devices().

* After the patch, we reject -drive if=T when T != none and the board
  didn't claim it.  This is known earlier, after
  machine_run_board_init().