This patch provides fault-injection capability for disk IO.
Boot option:
fail_make_request=<probability>,<interval>,<space>,<times>
<interval> -- specifies the interval of failures.
<probability> -- specifies how often it should fail in percent.
<space> -- specifies the size of free space where disk IO can be issued
safely in bytes.
<times> -- specifies how many times failures may happen at most.
Debugfs:
/debug/fail_make_request/interval
/debug/fail_make_request/probability
/debug/fail_make_request/specifies
/debug/fail_make_request/times
Example:
fail_make_request=10,100,0,-1
echo 1 > /sys/blocks/hda/hda1/make-it-fail
generic_make_request() on /dev/hda1 fails once per 10 times.
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
check_partition() stops its probe once it hits an I/O error from the
partition checkers. This would prevent the actual partition checker
getting a chance to verify the partition.
So this patch lets check_partition() continue probing untill it hits a
success while recording the I/O error which might have been reported by the
checking routines.
Also, it does some cleanup of the partition methods for ibm, atari and
amiga to return -1 upon hitting an I/O error.
Signed-off-by: Suzuki K P <suzuki@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The current rescan_partition implementation ignores the errors that comes from
the lower layer. It reports success for unknown partitions as well as I/O
error cases while reading the partition information.
The unknown partition is not (and will not be) considered as an error in the
kernel, since there are legal users of it (e.g, members of a RAID5 MD Device
or a new disk which is not partitioned at all ). Changing this behaviour
would scare the user about a serious problem with their disk and is not
recommended. Thus for both "unknown partitions" to the Linux (eg., DEC
VMS,Novell Netware) and the legal users of NULL partition, would still be
reported as "SUCCESS".
The patch attached here, scares the user about something which he does need to
worry about. i.e, returning -EIO on disk I/O errors while reading the
partition information.
Signed-off-by: Suzuki K P <suzuki@in.ibm.com>
Cc: Erik Mouw <erik@harddisk-recovery.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Handle errors thrown in disk_sysfs_symlinks(), and propagate back to
caller.
The callers and associated functions don't do a real good job of handling
kobject errors anyway (add_partition, register_disk, rescan_partitions), so
this should do until something better comes along.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Change the partition code in fs/partitions/check.c to initialize a newly
detected partition's policy field with that of the containing block device
(see patch below).
My reasoning is that function set_disk_ro() in block/genhd.c modifies the
policy field (read-only indicator) of a disk and all contained partitions.
When a partition is detected after the call to set_disk_ro(), the policy
field of this partition will currently not inherit the disk's policy field.
This behavior poses a problem in cases where a block device can be
'logically de- and reactivated' like e.g. the s390 DASD driver because
partition detection may run after the policy field has been modified.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Acked-by: Al Viro <viro@ftp.linux.org.uk>
Makes-sense-to: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Sometimes partitions claim to be larger than the reported capacity of a
disk device. This patch makes the kernel warn about those partitions.
We still permit these patitions to be used. Quoting Andries Brouwer
<Andries.Brouwer@cwi.nl>:
Case 1: The kernel is mistaken about the size of the disk. (There are
commands to clip a disk to a certain capacity, there are jumpers to tell a
disk that it should report a certain capacity etc. Usually this is because
of BIOS bugs. In bad cases the machine will crash in the BIOS and hence fail
to boot if the disk reports full capacity.) In such cases actually accessing
the blocks of the partition may work fine, or may work fine after running an
unclip utility. I wrote "setmax" some years ago precisely for this reason.
Case 2: There was a messy partition table (maybe just a rounding error) but
the actual filesystem on the partition is contained in the physical disk.
Now using the filesystem goes without problem.
Case 3: Both partition and filesystem extend beyond the end of the disk. In
forensic or debugging situations one often uses a copy of the start of a
disk. Now access beyond the end gives an expected I/O error.
Signed-off-by: Mike Miller <mike.miller@hp.com>
Signed-off-by: Stephen Cameron <steve.cameron@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add read_mapping_page() which is used for callers that pass
mapping->a_ops->readpage as the filler for read_cache_page. This removes
some duplication from filesystem code.
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Like the SUBSYTEM= key we find in the environment of the uevent, this
creates a generic "subsystem" link in sysfs for every device. Userspace
usually doesn't care at all if its a "class" or a "bus" device. This
provides an unified way to determine the subsytem of a device, regardless
of the way the driver core has created it.
Signed-off-by: Kay Sievers <kay.sievers@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Make sure to clear the driverfs_dev pointer when we do del_gendisk() (on
disk removal), so that other users that may still have a ref to the disk
won't try to use the stale pointer.
Also move the KOBJ_REMOVE uevent handler up, so that the uevent still
has access to the driverfs_dev data.
This all should hopefully fix the problems with MMC umounts after device
removals that caused commit 56cf6504fc and
its reversal (1a2acc9e92).
Original problem reported by Todd Blumer and others.
Acked-by: Greg KH <gregkh@suse.de>
Cc: Russell King <rmk+lkml@arm.linux.org.uk>
Cc: James Bottomley <James.Bottomley@SteelEye.com>
Cc: Erik Mouw <erik@harddisk-recovery.com>
Cc: Andrew Vasquez <andrew.vasquez@qlogic.com>
Cc: Todd Blumer <todd@sdgsystems.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
As noted further on the this file, some block devices have a / in their
name, so fix the "block:..." symlink name the same as the /sys/block name.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
[BLOCK] delay all uevents until partition table is scanned
Here we delay the annoucement of all block device events until the
disk's partition table is scanned and all partition devices are already
created and sysfs is populated.
We have a bunch of old bugs for removable storage handling where we
probe successfully for a filesystem on the raw disk, but at the
same time the kernel recognizes a partition table and creates partition
devices.
Currently there is no sane way to tell if partitions will show up or not
at the time the disk device is announced to userspace. With the delayed
events we can simply skip any probe for a filesystem on the raw disk when
we find already present partitions.
Signed-off-by: Kay Sievers <kay.sievers@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Remove all the CONFIG_SYSFS stuff. That's supposed to all be implemented up
in header files.
Yes, the CONFIG_SYSFS=n data structures will be a little larger than
necessary, but that's a tradeoff we can decide to make.
Cc: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Creating "slaves" and "holders" directories in /sys/block/<disk> and
creating "holders" directory under /sys/block/<disk>/<partition>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The Rio Karma portable MP3 player has its own proprietary partition table.
The partition layout is similar to a DOS boot sector but it begins at a
different offset and uses a different magic number (0xAB56 instead of
0xAA55). Add support for it to enable mounting the device.
Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Block devices need to add the block device name to the symlink they put
in the device directory, otherwise multiple symlinks of the same name
can be created. This matches the class system, which works the same
way, we just forgot to convert block at the same time.
Cc: Pete Zaitcev <zaitcev@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Leave the overloaded "hotplug" word to susbsystems which are handling
real devices. The driver core does not "plug" anything, it just exports
the state to userspace and generates events.
Signed-off-by: Kay Sievers <kay.sievers@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Instead of having ->read_sectors and ->write_sectors, combine the two
into ->sectors[2] and similar for the other fields. This saves a branch
several places in the io path, since we don't have to care for what the
actual io direction is. On my x86-64 box, that's 200 bytes less text in
just the core (not counting the various drivers).
Signed-off-by: Jens Axboe <axboe@suse.de>
A "coldplug + udevstart" can be simple like this:
for i in /sys/block/*/*/uevent; do echo 1 > $i; done
for i in /sys/class/*/*/uevent; do echo 1 > $i; done
for i in /sys/bus/*/devices/*/uevent; do echo 1 > $i; done
Signed-off-by: Kay Sievers <kay.sievers@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
struct gendisk has these two fields: stamp, stamp_idle. Update to
stamp_idle is always in sync with stamp and they are always the same.
Therefore, it does not add any value in having two fields tracking
same timestamp. Suggest to remove it.
Also, we should only update gendisk stats with non-zero value.
Advantage is that we don't have to needlessly calculate memory address,
and then add zero to the content.
Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Signed-off-by: Jens Axboe <axboe@suse.de>
This patch makes the following changes to the msdos partition code:
- remove CONFIG_NEC98_PARTITION leftovers
- make parse_bsd static
This patch was already ACK'ed by Andries Brouwer.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
kobject_add() and kobject_del() don't emit hotplug events anymore. Do it
ourselves if we are finished populating the device directory.
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Akinobu Mita