![]() 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> |
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.. | ||
raid6test | ||
.gitignore | ||
bitmap.c | ||
dm-bio-list.h | ||
dm-bio-record.h | ||
dm-crypt.c | ||
dm-emc.c | ||
dm-exception-store.c | ||
dm-hw-handler.c | ||
dm-hw-handler.h | ||
dm-io.c | ||
dm-io.h | ||
dm-ioctl.c | ||
dm-linear.c | ||
dm-log.c | ||
dm-log.h | ||
dm-mpath.c | ||
dm-mpath.h | ||
dm-path-selector.c | ||
dm-path-selector.h | ||
dm-raid1.c | ||
dm-round-robin.c | ||
dm-snap.c | ||
dm-snap.h | ||
dm-stripe.c | ||
dm-table.c | ||
dm-target.c | ||
dm-zero.c | ||
dm.c | ||
dm.h | ||
faulty.c | ||
Kconfig | ||
kcopyd.c | ||
kcopyd.h | ||
linear.c | ||
Makefile | ||
md.c | ||
mktables.c | ||
multipath.c | ||
raid0.c | ||
raid1.c | ||
raid5.c | ||
raid6.h | ||
raid6algos.c | ||
raid6altivec.uc | ||
raid6int.uc | ||
raid6mmx.c | ||
raid6recov.c | ||
raid6sse1.c | ||
raid6sse2.c | ||
raid6x86.h | ||
raid10.c | ||
unroll.pl | ||
xor.c |