linux/drivers/md
David Howells 9361401eb7 [PATCH] BLOCK: Make it possible to disable the block layer [try #6]
Make it possible to disable the block layer.  Not all embedded devices require
it, some can make do with just JFFS2, NFS, ramfs, etc - none of which require
the block layer to be present.

This patch does the following:

 (*) Introduces CONFIG_BLOCK to disable the block layer, buffering and blockdev
     support.

 (*) Adds dependencies on CONFIG_BLOCK to any configuration item that controls
     an item that uses the block layer.  This includes:

     (*) Block I/O tracing.

     (*) Disk partition code.

     (*) All filesystems that are block based, eg: Ext3, ReiserFS, ISOFS.

     (*) The SCSI layer.  As far as I can tell, even SCSI chardevs use the
     	 block layer to do scheduling.  Some drivers that use SCSI facilities -
     	 such as USB storage - end up disabled indirectly from this.

     (*) Various block-based device drivers, such as IDE and the old CDROM
     	 drivers.

     (*) MTD blockdev handling and FTL.

     (*) JFFS - which uses set_bdev_super(), something it could avoid doing by
     	 taking a leaf out of JFFS2's book.

 (*) Makes most of the contents of linux/blkdev.h, linux/buffer_head.h and
     linux/elevator.h contingent on CONFIG_BLOCK being set.  sector_div() is,
     however, still used in places, and so is still available.

 (*) Also made contingent are the contents of linux/mpage.h, linux/genhd.h and
     parts of linux/fs.h.

 (*) Makes a number of files in fs/ contingent on CONFIG_BLOCK.

 (*) Makes mm/bounce.c (bounce buffering) contingent on CONFIG_BLOCK.

 (*) set_page_dirty() doesn't call __set_page_dirty_buffers() if CONFIG_BLOCK
     is not enabled.

 (*) fs/no-block.c is created to hold out-of-line stubs and things that are
     required when CONFIG_BLOCK is not set:

     (*) Default blockdev file operations (to give error ENODEV on opening).

 (*) Makes some /proc changes:

     (*) /proc/devices does not list any blockdevs.

     (*) /proc/diskstats and /proc/partitions are contingent on CONFIG_BLOCK.

 (*) Makes some compat ioctl handling contingent on CONFIG_BLOCK.

 (*) If CONFIG_BLOCK is not defined, makes sys_quotactl() return -ENODEV if
     given command other than Q_SYNC or if a special device is specified.

 (*) In init/do_mounts.c, no reference is made to the blockdev routines if
     CONFIG_BLOCK is not defined.  This does not prohibit NFS roots or JFFS2.

 (*) The bdflush, ioprio_set and ioprio_get syscalls can now be absent (return
     error ENOSYS by way of cond_syscall if so).

 (*) The seclvl_bd_claim() and seclvl_bd_release() security calls do nothing if
     CONFIG_BLOCK is not set, since they can't then happen.

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2006-09-30 20:52:31 +02:00
..
raid6test [PATCH] RAID6 Altivec fix 2005-09-17 11:49:58 -07:00
.gitignore gitignore: misc files 2006-01-01 22:21:50 +01:00
bitmap.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
dm-bio-list.h [PATCH] device-mapper snapshot: bio_list fix 2005-11-22 09:14:31 -08:00
dm-bio-record.h
dm-crypt.c [BLOCK] dm-crypt: trivial comment improvements 2006-09-21 11:46:27 +10:00
dm-emc.c [PATCH] Split struct request ->flags into two parts 2006-09-30 20:23:37 +02:00
dm-exception-store.c [PATCH] dm: improve error message consistency 2006-06-26 09:58:36 -07:00
dm-hw-handler.c BUG_ON() Conversion in md/dm-hw-handler.c 2006-03-24 18:36:27 +01:00
dm-hw-handler.h
dm-io.c [PATCH] mempool: use common mempool kmalloc allocator 2006-03-26 08:56:59 -08:00
dm-io.h [PATCH] device-mapper: remove unused definition 2006-01-06 08:34:00 -08:00
dm-ioctl.c [PATCH] devfs: Remove the miscdevice devfs_name field as it's no longer needed 2006-06-26 12:25:08 -07:00
dm-linear.c [PATCH] dm: improve error message consistency 2006-06-26 09:58:36 -07:00
dm-log.c [PATCH] dm: improve error message consistency 2006-06-26 09:58:36 -07:00
dm-log.h
dm-mpath.c [PATCH] dm: BUG/OOPS fix 2006-08-14 12:54:29 -07:00
dm-mpath.h
dm-path-selector.c BUG_ON() Conversion in md/dm-path-selector.c 2006-03-26 18:21:58 +02:00
dm-path-selector.h
dm-raid1.c [PATCH] dm: Fix deadlock under high i/o load in raid1 setup. 2006-08-27 11:01:28 -07:00
dm-round-robin.c [PATCH] dm: improve error message consistency 2006-06-26 09:58:36 -07:00
dm-snap.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
dm-snap.h [PATCH] device-mapper snapshot: load metadata on creation 2006-02-01 08:53:10 -08:00
dm-stripe.c [PATCH] dm: improve error message consistency 2006-06-26 09:58:36 -07:00
dm-table.c [PATCH] dm: improve error message consistency 2006-06-26 09:58:36 -07:00
dm-target.c [PATCH] dm: improve error message consistency 2006-06-26 09:58:36 -07:00
dm-zero.c [PATCH] dm: improve error message consistency 2006-06-26 09:58:36 -07:00
dm.c [PATCH] devfs: Last little devfs cleanups throughout the kernel tree. 2006-06-26 12:25:09 -07:00
dm.h [PATCH] dm: improve error message consistency 2006-06-26 09:58:36 -07:00
faulty.c [PATCH] md: allow array level to be set textually via sysfs 2006-01-06 08:34:09 -08:00
Kconfig [PATCH] BLOCK: Make it possible to disable the block layer [try #6] 2006-09-30 20:52:31 +02:00
kcopyd.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
kcopyd.h
linear.c [PATCH] md: Fix a bug that recently crept into md/linear 2006-08-06 08:57:46 -07:00
Makefile [PATCH] md: merge raid5 and raid6 code 2006-06-26 09:58:37 -07:00
md.c [PATCH] md: avoid backward event updates in md superblock when degraded. 2006-08-27 11:01:31 -07:00
mktables.c
multipath.c [PATCH] mempool: use common mempool kzalloc allocator 2006-03-26 08:56:59 -08:00
raid0.c [PATCH] md: fix possible oops when starting a raid0 array 2006-05-23 10:35:31 -07:00
raid1.c [PATCH] md: Fix issues with referencing rdev in md/raid1 2006-09-01 11:39:08 -07:00
raid5.c [PATCH] md: include sector number in messages about corrected read errors 2006-07-10 13:24:17 -07:00
raid6.h [PATCH] RAID6 Altivec fix 2005-09-17 11:49:58 -07:00
raid6algos.c [PATCH] drivers/md/raid6algos.c: fix a NULL dereference 2006-06-23 07:43:08 -07:00
raid6altivec.uc [PATCH] RAID6 Altivec fix 2005-09-17 11:49:58 -07:00
raid6int.uc
raid6mmx.c
raid6recov.c
raid6sse1.c
raid6sse2.c
raid6x86.h
raid10.c [PATCH] md: include sector number in messages about corrected read errors 2006-07-10 13:24:17 -07:00
unroll.pl
xor.c