block: remove pktcdvd driver

This driver has long outlived it's utility, and it's broken and unloved.
The main use case for this was direct mount with UDF of cd-rw drives
that required 32kb packets. It would collect writes into that size and
write them out in multiples of that. That's not a common use case
anymore, the world has moved on from those kinds of media. To make
matters worse, it's actively breaking setups where it's not even
required or useful.

Link: https://lore.kernel.org/linux-block/fxg6dksau4jsk3u5xldlyo2m7qgiux6vtdrz5rywseotsouqdv@urcrwz6qtd3r/
Signed-off-by: Jens Axboe <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Hannes Reinecke <[email protected]>

Author: axboe

Documentation/ABI/testing/debugfs-pktcdvd

@@ -256,49 +256,6 @@ config BLK_DEV_RAM_SIZE
 	  The default value is 4096 kilobytes. Only change this if you know
 	  what you are doing.
 
-config CDROM_PKTCDVD
-	tristate "Packet writing on CD/DVD media (DEPRECATED)"
-	depends on !UML
-	depends on SCSI
-	select CDROM
-	help
-	  Note: This driver is deprecated and will be removed from the
-	  kernel in the near future!
-
-	  If you have a CDROM/DVD drive that supports packet writing, say
-	  Y to include support. It should work with any MMC/Mt Fuji
-	  compliant ATAPI or SCSI drive, which is just about any newer
-	  DVD/CD writer.
-
-	  Currently only writing to CD-RW, DVD-RW, DVD+RW and DVDRAM discs
-	  is possible.
-	  DVD-RW disks must be in restricted overwrite mode.
-
-	  See the file <file:Documentation/cdrom/packet-writing.rst>
-	  for further information on the use of this driver.
-
-	  To compile this driver as a module, choose M here: the
-	  module will be called pktcdvd.
-
-config CDROM_PKTCDVD_BUFFERS
-	int "Free buffers for data gathering"
-	depends on CDROM_PKTCDVD
-	default "8"
-	help
-	  This controls the maximum number of active concurrent packets. More
-	  concurrent packets can increase write performance, but also require
-	  more memory. Each concurrent packet will require approximately 64Kb
-	  of non-swappable kernel memory, memory which will be allocated when
-	  a disc is opened for writing.
-
-config CDROM_PKTCDVD_WCACHE
-	bool "Enable write caching"
-	depends on CDROM_PKTCDVD
-	help
-	  If enabled, write caching will be set for the CD-R/W device. For now
-	  this option is dangerous unless the CD-RW media is known good, as we
-	  don't do deferred write error handling yet.
-
 config ATA_OVER_ETH
 	tristate "ATA over Ethernet support"
 	depends on NET

Documentation/ABI/testing/sysfs-class-pktcdvd

@@ -23,7 +23,6 @@ obj-$(CONFIG_AMIGA_Z2RAM)	+= z2ram.o
 obj-$(CONFIG_N64CART)		+= n64cart.o
 obj-$(CONFIG_BLK_DEV_RAM)	+= brd.o
 obj-$(CONFIG_BLK_DEV_LOOP)	+= loop.o
-obj-$(CONFIG_CDROM_PKTCDVD)	+= pktcdvd.o
 obj-$(CONFIG_SUNVDC)		+= sunvdc.o
 
 obj-$(CONFIG_BLK_DEV_NBD)	+= nbd.o