aha/mm
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
..
allocpercpu.c [PATCH] Extract the allocpercpu functions from the slab allocator 2006-09-26 08:48:51 -07:00
bootmem.c [PATCH] bootmem: use MAX_DMA_ADDRESS instead of LOW32LIMIT 2006-09-26 08:48:49 -07:00
bounce.c [PATCH] BLOCK: Separate the bounce buffering code from the highmem code [try #6] 2006-09-30 20:32:11 +02:00
fadvise.c [PATCH] fadvise() make POSIX_FADV_NOREUSE a no-op 2006-08-06 08:57:47 -07:00
filemap.c [PATCH] BLOCK: Make it possible to disable the block layer [try #6] 2006-09-30 20:52:31 +02:00
filemap.h [PATCH] generic_file_buffered_write(): handle zero-length iovec segments 2006-06-29 10:26:20 -07:00
filemap_xip.c [PATCH] mark address_space_operations const 2006-06-28 14:59:04 -07:00
fremap.c [PATCH] mm: small cleanup of install_page() 2006-09-26 08:48:44 -07:00
highmem.c [PATCH] BLOCK: Separate the bounce buffering code from the highmem code [try #6] 2006-09-30 20:32:11 +02:00
hugetlb.c [PATCH] NUMA: Add zone_to_nid function 2006-09-26 08:48:52 -07:00
internal.h [PATCH] mm: VM_BUG_ON 2006-09-26 08:48:44 -07:00
Kconfig Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6 2006-06-29 10:49:17 -07:00
madvise.c
Makefile [PATCH] BLOCK: Make it possible to disable the block layer [try #6] 2006-09-30 20:52:31 +02:00
memory.c [PATCH] mm: fix a race condition under SMC + COW 2006-09-29 09:18:03 -07:00
memory_hotplug.c [PATCH] call mm/page-writeback.c:set_ratelimit() when new pages are hot-added 2006-09-29 09:18:22 -07:00
mempolicy.c [PATCH] GFP_THISNODE for the slab allocator 2006-09-27 08:26:12 -07:00
mempool.c [PATCH] dm: work around mempool_alloc, bio_alloc_bioset deadlocks 2006-09-01 11:39:09 -07:00
migrate.c [PATCH] BLOCK: Make it possible to disable the block layer [try #6] 2006-09-30 20:52:31 +02:00
mincore.c
mlock.c
mmap.c [PATCH] ZVC: Support NR_SLAB_RECLAIMABLE / NR_SLAB_UNRECLAIMABLE 2006-09-26 08:48:51 -07:00
mmzone.c [PATCH] mm/mmzone.c: EXPORT_UNUSED_SYMBOL 2006-07-10 13:24:17 -07:00
mprotect.c [PATCH] mm: optimize the new mprotect() code a bit 2006-09-26 08:48:44 -07:00
mremap.c [PATCH] lockdep: annotate mm 2006-07-03 15:27:07 -07:00
msync.c [PATCH] mm: msync() cleanup 2006-09-26 08:48:45 -07:00
nommu.c [PATCH] NOMMU: Make futexes work under NOMMU conditions 2006-09-27 08:26:15 -07:00
oom_kill.c [PATCH] oom: don't kill current when another OOM in progress 2006-09-29 09:18:21 -07:00
page-writeback.c [PATCH] BLOCK: Make it possible to disable the block layer [try #6] 2006-09-30 20:52:31 +02:00
page_alloc.c [PATCH] mm/page_alloc: use NULL instead of 0 for ptr 2006-09-27 08:26:13 -07:00
page_io.c [PATCH] swsusp: read speedup 2006-09-26 08:48:58 -07:00
pdflush.c [PATCH] pdflush: handle resume wakeups 2006-06-25 10:01:06 -07:00
prio_tree.c
readahead.c spelling fixes 2006-06-26 18:35:02 +02:00
rmap.c [PATCH] mm: tracking shared dirty pages 2006-09-26 08:48:44 -07:00
shmem.c [PATCH] Access Control Lists for tmpfs 2006-09-29 09:18:24 -07:00
shmem_acl.c [PATCH] Access Control Lists for tmpfs 2006-09-29 09:18:24 -07:00
slab.c [PATCH] single bit flip detector 2006-09-29 09:18:10 -07:00
slob.c [PATCH] Make kmem_cache_destroy() return void 2006-09-27 08:26:11 -07:00
sparse.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
swap.c [PATCH] mm/: make functions static 2006-09-26 08:48:45 -07:00
swap_state.c [PATCH] lockdep: locking init debugging improvement 2006-07-03 15:27:02 -07:00
swapfile.c [PATCH] valid_swaphandles() fix 2006-09-29 09:18:23 -07:00
thrash.c
tiny-shmem.c [PATCH] devfs: Remove the devfs_fs_kernel.h file from the tree 2006-06-26 12:25:08 -07:00
truncate.c [PATCH] BLOCK: Make it possible to disable the block layer [try #6] 2006-09-30 20:52:31 +02:00
util.c
vmalloc.c [PATCH] Mark __remove_vm_area() static 2006-09-27 08:26:13 -07:00
vmscan.c [PATCH] page invalidation cleanup 2006-09-27 08:26:12 -07:00
vmstat.c [PATCH] zone_statistics: Use hot node instead of cold zone_pgdat 2006-09-27 08:26:13 -07:00