raw-posix: Deprecate host floppy passthrough

Raise your hand if you have a physical floppy drive in a computer
you've powered on in 2015.  Okay, I see we got a few weirdos in the
audience.  That's okay, weirdos are welcome here.

Kidding aside, media change detection doesn't fully work, isn't going
to be fixed, and floppy passthrough just isn't earning its keep
anymore.

Deprecate block driver host_floppy now, so we can drop it after a
grace period.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block/raw-posix.c

@@ -2387,6 +2387,8 @@ static int floppy_open(BlockDriverState *bs, QDict *options, int flags,
     s->fd = -1;
     s->fd_media_changed = 1;
 
+    error_report("Host floppy pass-through is deprecated");
+    error_printf("Support for it will be removed in a future release.\n");
     return 0;
 }
 

qapi/block-core.json

@@ -218,6 +218,7 @@
 #       'host_floppy', 'http', 'https', 'nbd', 'parallels', 'qcow',
 #       'qcow2', 'raw', 'tftp', 'vdi', 'vmdk', 'vpc', 'vvfat'
 #       2.2: 'archipelago' added, 'cow' dropped
+#       2.3: 'host_floppy' deprecated
 #
 # @backing_file: #optional the name of the backing file (for copy-on-write)
 #
@@ -1245,6 +1246,7 @@
 # Drivers that are supported in block device operations.
 #
 # @host_device, @host_cdrom, @host_floppy: Since 2.1
+# @host_floppy: deprecated since 2.3
 #
 # Since: 2.0
 ##

qemu-doc.texi

@@ -736,8 +736,7 @@ devices. We describe here the usage for QEMU version >= 0.8.3.
 
 On Linux, you can directly use the host device filename instead of a
 disk image filename provided you have enough privileges to access
-it. For example, use @file{/dev/cdrom} to access to the CDROM or
+it. For example, use @file{/dev/cdrom} to access to the CDROM.
-@file{/dev/fd0} for the floppy.
 
 @table @code
 @item CD
@@ -749,6 +748,8 @@ You can specify a floppy device even if no floppy is loaded. Floppy
 removal is currently not detected accurately (if you change floppy
 without doing floppy access while the floppy is not loaded, the guest
 OS will think that the same floppy is loaded).
+Use of the host's floppy device is deprecated, and support for it will
+be removed in a future release.
 @item Hard disks
 Hard disks can be used. Normally you must specify the whole disk
 (@file{/dev/hdb} instead of @file{/dev/hdb1}) so that the guest OS can

qemu-options.hx

@@ -419,8 +419,7 @@ STEXI
 @item -fdb @var{file}
 @findex -fda
 @findex -fdb
-Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can
+Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}).
-use the host floppy by using @file{/dev/fd0} as filename (@pxref{host_drives}).
 ETEXI
 
 DEF("hda", HAS_ARG, QEMU_OPTION_hda,

qmp-commands.hx

@@ -2154,7 +2154,7 @@ Each json-object contain the following:
          - "drv": driver format name (json-string)
              - Possible values: "blkdebug", "bochs", "cloop", "dmg",
                                 "file", "file", "ftp", "ftps", "host_cdrom",
-                                "host_device", "host_floppy", "http", "https",
+                                "host_device", "http", "https",
                                 "nbd", "parallels", "qcow", "qcow2", "raw",
                                 "tftp", "vdi", "vmdk", "vpc", "vvfat"
          - "backing_file": backing file name (json-string, optional)