Get rid of any functions that test for these bits and make callers
use bio_rw_flagged() directly. Then it is at least directly apparent
what variable and flag they check.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
As revalidate_disk calls check_disk_size_change, it will cause
any capacity change of a gendisk to be propagated to the blockdev
inode. So use that instead of mucking about with locks and
i_size_write.
Also add a call to revalidate_disk in do_md_run and a few other places
where the gendisk capacity is changed.
Signed-off-by: NeilBrown <neilb@suse.de>
This patch replaces md_integrity_check() by two new public functions:
md_integrity_register() and md_integrity_add_rdev() which are both
personality-independent.
md_integrity_register() is called from the ->run and ->hot_remove
methods of all personalities that support data integrity. The
function iterates over the component devices of the array and
determines if all active devices are integrity capable and if their
profiles match. If this is the case, the common profile is registered
for the mddev via blk_integrity_register().
The second new function, md_integrity_add_rdev() is called from the
->hot_add_disk methods, i.e. whenever a new device is being added
to a raid array. If the new device does not support data integrity,
or has a profile different from the one already registered, data
integrity for the mddev is disabled.
For raid0 and linear, only the call to md_integrity_register() from
the ->run method is necessary.
Signed-off-by: Andre Noll <maan@systemlinux.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Switch MD over to the new disk_stack_limits() function which checks for
aligment and adjusts preferred I/O sizes when stacking.
Also indicate preferred I/O sizes where applicable.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Current, when we update the 'conf' structure, when adding a
drive to a linear array, we keep the old version around until
the array is finally stopped, as it is not safe to free it
immediately.
Now that we have rcu protection on all accesses to 'conf',
we can use call_rcu to free it more promptly.
Signed-off-by: NeilBrown <neilb@suse.de>
Due to the lack of memory ordering guarantees, we may have races around
mddev->conf.
In particular, the correct contents of the structure we get from
dereferencing ->private might not be visible to this CPU yet, and
they might not be correct w.r.t mddev->raid_disks.
This patch addresses the problem using rcu protection to avoid
such race conditions.
Signed-off-by: SandeepKsinha <sandeepksinha@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
If the superblock of a component device indicates the presence of a
bitmap but the corresponding raid personality does not support bitmaps
(raid0, linear, multipath, faulty), then something is seriously wrong
and we'd better refuse to run such an array.
Currently, this check is performed while the superblocks are examined,
i.e. before entering personality code. Therefore the generic md layer
must know which raid levels support bitmaps and which do not.
This patch avoids this layer violation without adding identical code
to various personalities. This is accomplished by introducing a new
public function to md.c, md_check_no_bitmap(), which replaces the
hard-coded checks in the superblock loading functions.
A call to md_check_no_bitmap() is added to the ->run method of each
personality which does not support bitmaps and assembly is aborted
if at least one component device contains a bitmap.
Signed-off-by: Andre Noll <maan@systemlinux.org>
Signed-off-by: NeilBrown <neilb@suse.de>
This is currently ensured by common code, but it is more reliable to
ensure it where it is needed in personality code.
All the other personalities that care already round the size to
the chunk_size. raid0 and linear are the only hold-outs.
Signed-off-by: NeilBrown <neilb@suse.de>
This patch renames the chunk_size field to chunk_sectors with the
implied change of semantics. Since
is_power_of_2(chunk_size) = is_power_of_2(chunk_sectors << 9)
= is_power_of_2(chunk_sectors)
these bits don't need an adjustment for the shift.
Signed-off-by: Andre Noll <maan@systemlinux.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Replace the linear search with binary search in which_dev.
Signed-off-by: Sandeep K Sinha <sandeepksinha@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Remove num_sectors from dev_info and replace start_sector with
end_sector. This makes a lot of comparisons much simpler.
Signed-off-by: Sandeep K Sinha <sandeepksinha@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Get rid of sector_div and hash table for linear raid and replace
with a linear search in which_dev.
The hash table adds a lot of complexity for little if any gain.
Ultimately a binary search will be used which will have smaller
cache foot print, a similar number of memory access, and no
divisions.
Signed-off-by: Sandeep K Sinha <sandeepksinha@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Having a macro just to cast a void* isn't really helpful.
I would must rather see that we are simply de-referencing ->private,
than have to know what the macro does.
So open code the macro everywhere and remove the pointless cast.
Signed-off-by: NeilBrown <neilb@suse.de>
Convert all external users of queue limits to using wrapper functions
instead of poking the request queue variables directly.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Get personalities out of the business of directly modifying
->array_sectors. Lays groundwork to introduce policy on when
->array_sectors can be modified.
Reviewed-by: Andre Noll <maan@systemlinux.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In preparation for giving userspace control over ->array_sectors we need
to be able to retrieve the 'default' size, and the 'anticipated' size
when a reshape is requested. For personalities that do not reshape emit
a warning if anything but the default size is requested.
In the raid5 case we need to update ->previous_raid_disks to make the
new 'default' size available.
Reviewed-by: Andre Noll <maan@systemlinux.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This patch renames the "size" field of struct mdk_rdev_s to
"sectors" and changes this field to store sectors instead of
blocks.
All users of this field, linear.c, raid0.c and md.c, are fixed up
accordingly which gets rid of many multiplications and divisions.
Signed-off-by: Andre Noll <maan@systemlinux.org>
Signed-off-by: NeilBrown <neilb@suse.de>
This makes the includes more explicit, and is preparation for moving
md_k.h to drivers/md/md.h
Remove include/raid/md.h as its only remaining use was to #include
other files.
Signed-off-by: NeilBrown <neilb@suse.de>
Move the headers with the local structures for the disciplines and
bitmap.h into drivers/md/ so that they are more easily grepable for
hacking and not far away. md.h is left where it is for now as there
are some uses from the outside.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: NeilBrown <neilb@suse.de>
ab5bd5cbc8 introduced the following
bug in linear software raid for large arrays on 32 bit machines:
which_dev() computes the device holding a given sector by shifting
down the sector number to a 32 bit range, dividing by the array
spacing and looking up the resulting index in the hash table of
the array.
Because the computed index might be slightly too small, a loop at
the end of which_dev() increases the index until the given sector
actually falls into the range of the device associated with that index.
The changes of the above mentioned commit caused this loop to check
whether the _index_ rather than the sector number is small enough,
effectively bypassing the loop and thus possibly returning the wrong
device.
As reported by Simon Kirby, this leads to errors such as
linear_make_request: Sector 2340486136 out of bounds on dev sdi: 156301312 sectors, offset 2109870464
Fix this bug by introducing a local variable for the index so that
the variable containing the passed sector is left unchanged.
Cc: stable@kernel.org
Signed-off-by: Andre Noll <maan@systemlinux.org>
Signed-off-by: NeilBrown <neilb@suse.de>
The rdev_for_each macro defined in <linux/raid/md_k.h> is identical to
list_for_each_entry_safe, from <linux/list.h>, it should be defined to
use list_for_each_entry_safe, instead of reinventing the wheel.
But some calls to each_entry_safe don't really need a safe version,
just a direct list_for_each_entry is enough, this could save a temp
variable (tmp) in every function that used rdev_for_each.
In this patch, most rdev_for_each loops are replaced by list_for_each_entry,
totally save many tmp vars; and only in the other situations that will call
list_del to delete an entry, the safe version is used.
Signed-off-by: Cheng Renquan <crquan@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
We currently oops with a divide error on starting a linear software
raid array consisting of at least two very small (< 500K) devices.
The bug is caused by the calculation of the hash table size which
tries to compute sector_div(sz, base) with "base" being zero due to
the small size of the component devices of the array.
Fix this by requiring the hash spacing to be at least one which
implies that also "base" is non-zero.
This bug has existed since about 2.6.14.
Cc: stable@kernel.org
Signed-off-by: Andre Noll <maan@systemlinux.org>
Signed-off-by: NeilBrown <neilb@suse.de>
