do_md_stop tests mddev->openers while holding ->open_mutex,
and fails if this count is too high.
So callers do not need to check mddev->openers and doing so isn't
very meaningful as they don't hold ->open_mutex so the number could
change.
So remove the unnecessary tests on mddev->openers.
These are not called often enough for there to be any gain in
an early test on ->open_mutex to avoid the need for a slightly more
costly mutex_lock call.
Signed-off-by: NeilBrown <neilb@suse.de>
Because bios will merge at block-layer,so bios-error may caused by other
bio which be merged into to the same request.
Using this flag,it will find exactly error-sector and not do redundant
operation like re-write and re-read.
V0->V1:Using REQ_FLUSH instead REQ_NOMERGE avoid bio merging at block
layer.
Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
For SSD, if request size exceeds specific value (optimal io size), request size
isn't important for bandwidth. In such condition, if making request size bigger
will cause some disks idle, the total throughput will actually drop. A good
example is doing a readahead in a two-disk raid1 setup.
So when should we split big requests? We absolutly don't want to split big
request to very small requests. Even in SSD, big request transfer is more
efficient. This patch only considers request with size above optimal io size.
If all disks are busy, is it worth doing a split? Say optimal io size is 16k,
two requests 32k and two disks. We can let each disk run one 32k request, or
split the requests to 4 16k requests and each disk runs two. It's hard to say
which case is better, depending on hardware.
So only consider case where there are idle disks. For readahead, split is
always better in this case. And in my test, below patch can improve > 30%
thoughput. Hmm, not 100%, because disk isn't 100% busy.
Such case can happen not just in readahead, for example, in directio. But I
suppose directio usually will have bigger IO depth and make all disks busy, so
I ignored it.
Note: if the raid uses any hard disk, we don't prevent merging. That will make
performace worse.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
SSD hasn't spindle, distance between requests means nothing. And the original
distance based algorithm sometimes can cause severe performance issue for SSD
raid.
Considering two thread groups, one accesses file A, the other access file B.
The first group will access one disk and the second will access the other disk,
because requests are near from one group and far between groups. In this case,
read balance might keep one disk very busy but the other relative idle. For
SSD, we should try best to distribute requests to as many disks as possible.
There isn't spindle move penality anyway.
With below patch, I can see more than 50% throughput improvement sometimes
depending on workloads.
The only exception is small requests can be merged to a big request which
typically can drive higher throughput for SSD too. Such small requests are
sequential reads. Unlike hard disk, sequential read which can't be merged (for
example direct IO, or read without readahead) can be ignored for SSD. Again
there is no spindle move penality. readahead dispatches small requests and such
requests can be merged.
Last patch can help detect sequential read well, at least if concurrent read
number isn't greater than raid disk number. In that case, distance based
algorithm doesn't work well too.
V2: For hard disk and SSD mixed raid, doesn't use distance based algorithm for
random IO too. This makes the algorithm generic for raid with SSD.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Currently the sequential read detection is global wide. It's natural to make it
per disk based, which can improve the detection for concurrent multiple
sequential reads. And next patch will make SSD read balance not use distance
based algorithm, where this change help detect truly sequential read for SSD.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
md/raid10: Export is_congested test.
In similar fashion to commits
11d8a6e3711ed7242e59
we export the RAID10 congestion checking function so that dm-raid.c can
make use of it and make use of the personality. The 'queue' and 'gendisk'
structures will not be available to the MD code when device-mapper sets
up the device, so we conditionalize access to these fields also.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
MD RAID1/RAID10: Move some macros from .h file to .c file
There are three macros (IO_BLOCKED,IO_MADE_GOOD,BIO_SPECIAL) which are defined
in both raid1.h and raid10.h. They are only used in there respective .c files.
However, if we wish to make RAID10 accessible to the device-mapper RAID
target (dm-raid.c), then we need to move these macros into the .c files where
they are used so that they do not conflict with each other.
The macros from the two files are identical and could be moved into md.h, but
I chose to leave the duplication and have them remain in the personality
files.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
MD RAID1: Rename the structure 'mirror_info' to 'raid1_info'
The same structure name ('mirror_info') is used by raid10. Each of these
structures are defined in there respective header files. If dm-raid is
to support both RAID1 and RAID10, the header files will be included and
the structure names must not collide. While only one of these structure
names needs to change, this patch adds consistency to the naming of the
structure.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
MD RAID10: Rename the structure 'mirror_info' to 'raid10_info'
The same structure name ('mirror_info') is used by raid1. Each of these
structures are defined in there respective header files. If dm-raid is
to support both RAID1 and RAID10, the header files will be included and
the structure names must not collide.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Commit outstanding metadata before returning the status for a dm thin
pool so that the numbers reported are as up-to-date as possible.
The commit is not performed if the device is suspended or if
the DM_NOFLUSH_FLAG is supplied by userspace and passed to the target
through a new 'status_flags' parameter in the target's dm_status_fn.
The userspace dmsetup tool will support the --noflush flag with the
'dmsetup status' and 'dmsetup wait' commands from version 1.02.76
onwards.
Tested-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Add read-only and fail-io modes to thin provisioning.
If a transaction commit fails the pool's metadata device will transition
to "read-only" mode. If a commit fails once already in read-only mode
the transition to "fail-io" mode occurs.
Once in fail-io mode the pool and all associated thin devices will
report a status of "Fail".
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Introduce dm_pool_abort_metadata to abort the current metadata
transaction. Generally this will only be called when bad things are
happening and dm-thin is trying to roll back to a good state for
read-only mode.
It's complicated by the fact that the metadata device may have failed
completely causing the abort to be unable to read the old transaction.
In this case the metadata object is placed in a 'fail' mode and
everything fails apart from destroying it.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Introduce dm_pool_metadata_set_read_only to put the underlying block
manager into read-only mode.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Introduce dm_bm_set_read_only to switch the block manager into a
read-only mode. To be used when dm-thin degrades due to io errors on
the metadata device.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Reduce the number of metadata commits by using
dm_thin_changed_this_transaction to check if metadata was changed on a
per thin device granularity.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Introduce dm_thin_changed_this_transaction to dm-thin-metadata to publish a
useful bit of information we're already tracking. This will help dm thin
decide when to commit.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Add a parameter to dm_pool_metadata_open to indicate whether or not an
unformatted metadata area should be formatted.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Tidy up error path in __open_metadata and __format_metadata in dm-thin-metadata.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Factor out __check_incompat_features and only call it once when we open
the metadata device rather than at the beginning of every transaction.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove some duplicate initialisation of struct dm_pool_metadata.
These pmd fields are initialised by both:
__format_metadata's calls to dm_btree_empty
__write_initial_superblock + __begin_transaction
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove 'create' parameter from __create_persistent_data_objects() in dm-thin-metadata.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Move the check for __superblock_all_zeroes from
__create_persistent_data_objects() down to __open_or_format_metadata in
dm-thin-metadata.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove nr_blocks arg from __create_persistent_data_objects in dm-thin-metadata.
It was always passed as zero.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Split __open_or_format_metadata into __format_metadata and __open_metadata in
dm-thin-metadata.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Clean up __open_or_format_metadata in dm-thin-metadata by using struct
dm_pool_metadata members to replace local variables.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Zero the unused uuid when initialising the metadata superblock.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Lift the call to __begin_transaction out of __write_initial_superblock in
dm-thin-metadata. Called higher up the call chain now.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Move dm_commit_pool_metadata inline into __write_initial_superblock in dm-thin-metadata.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Factor out __write_initial_superblock and also pull some other initial
creation code out of dm_pool_metadata_open.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Lift some initialisation out of __open_or_format_metadata in dm-thin-metadata.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Factor __destroy_persistent_data_objects out of dm_pool_metadata_close.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Move block manager creation and the check for unformatted metadata into
__create_persistent_data_objects().
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Rename init_pmd to __create_persistent_data_objects in dm-thin-metadata.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Introduce wrappers to handle write locking the superblock
appropriately.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Stop using dm_bm_unlock_move when shadowing blocks in the transaction
manager as an optimisation and remove the function as it is then no
longer used.
Some code, such as the space maps, keeps using on-disk data structures
from the previous transaction. It can do this because blocks won't
be reallocated until the subsequent transaction. Using
dm_bm_unlock_move to copy blocks sounds like a win, but it forces a
synchronous read should the old block be accessed.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Tidy the transaction manager creation functions.
They no longer lock the superblock. Superblock locking is pulled out to
the caller.
Also export dm_bm_write_lock_zero.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove an optimisation that tracks whether or not a thin metadata commit
is needed.
If dm_pool_commit_metadata() is called and no changes have been made
to the metadata then this optimisation avoided writing to disk.
Removing because we're going to do something better later.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch introduces a separate struct for the block_manager.
It also uses IS_ERR to check the return value of dm_bufio_client_create
instead of testing incorrectly for NULL.
Prior to this patch a struct dm_block_manager was really an alias for
a struct dm_bufio_client. We want to add some functionality to the
block manager that will require extra fields, so this one to one
mapping is no longer valid.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Factor __setup_btree_details out of init_pmd in dm-thin-metadata.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The thin provisioning target commits internal metadata on flush. So it
should receive flushes regardless of whether the underlying devices
support them.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Allow targets to override the 'supports flush' calculation.
Set 'flush_supported' if a target needs to receive flushes regardless of
whether or not its underlying devices have support.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Introduce bitmap_index_changed to track whether or not the index changed
then only commit a space map if it did.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Unlock the superblock even if initial dm_bufio_write_dirty_buffers fails.
Also, remove redundant flush calls. dm_bm_flush_and_unlock's calls to
dm_bufio_write_dirty_buffers already result in dm_bufio_issue_flush
being called.
This avoids warnings about unflushed dirty buffers from bufio.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
There's no need to break sharing, triggering a copy, for a write that has no
data (i.e. a flush).
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Fix memory leak in process_prepared_mapping by always freeing
the dm_thin_new_mapping structs from the mapping_pool mempool on
the error paths.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Rename sector to cc_sector in dm-crypt's convert_context struct.
This is preparation for a future patch that merges dm_io and
convert_context which both have a "sector" field.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Store the crypt_config struct pointer directly in struct dm_crypt_io
instead of the dm_target struct pointer.
Target information is never used - only target->private is referenced,
thus we can change it to point directly to struct crypt_config.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Move static dm-crypt cipher data out of per-cpu structure.
Cipher information is static, so it does not have to be in a per-cpu
structure.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
In preparation for RAID10 inclusion in dm-raid, we move the sectors_per_dev
calculation later in the device creation process. This is because we won't
know up-front how many stripes vs how many mirrors there are which will
change the calculation.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
There are two dm crypt structures that have a field called "pending".
This patch renames them to "cc_pending" and "io_pending" to reduce confusion
and ease searching the code.
Also remove unnecessary initialisation of r in crypt_convert_block().
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
In preparation for RAID10 addition to dm-raid, we change an 'if' conditional
to a 'switch' conditional to make it easier to see what is being checked for
each RAID type.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
A SCSI device handler might get attached to a device during the
initial device scan. We do not necessarily want to override
this when loading a multipath table, so this patch adds a new
multipath feature argument "retain_attached_hw_handler".
During SCSI device scan all loaded SCSI device handlers will be
consulted for a match (via scsi_dh's provided .match). If a match is
found that device handler will be attached. We need a way to have
userspace multipathd's provided 'hw_handler' not override the already
attached hardware handler.
When specifying the new feature 'retain_attached_hw_handler' multipath
will use the currently attached hardware handler instead of trying to
attach the one specified during table load. If no hardware handler is
attached the specified hardware handler will still be used.
Leverages scsi_dh_attach's ability to increment the scsi_dh's reference
count if the same scsi_dh name is provided when attaching - currently
attached scsi_dh name is determined with scsi_dh_attached_handler_name.
Depends upon commit 7e8a74b177
("[SCSI] scsi_dh: add scsi_dh_attached_handler_name").
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Tested-by: Babu Moger <babu.moger@netapp.com>
Reviewed-by: Chandra Seetharaman <sekharan@us.ibm.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
dm-thin will be most likely used with a block size that is a power of
two. So it should be optimized for this case.
This patch changes division and modulo operations to shifts and bit
masks if block size is a power of two.
A test that bi_sector is divisible by a block size is removed from
io_overlaps_block. Device mapper never sends bios that span a block
boundary. Consequently, if we tested that bi_size is equivalent to block
size, bi_sector must already be on a block boundary.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch sets the variable "ti->split_discard_requests" for the dm thin
target so that device mapper core splits discard requests on a block
boundary.
Consequently, a discard request that spans multiple blocks is never sent
to dm-thin. The patch also removes some code in process_discard that
deals with discards that span multiple blocks.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch introduces a new variable split_discard_requests. It can be
set by targets so that discard requests are split on max_io_len
boundaries.
When split_discard_requests is not set, discard requests are only split on
boundaries between targets, as was the case before this patch.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Non power of 2 blocksize support is needed to properly align thinp IO
on storage that has non power of 2 optimal IO sizes (e.g. RAID6 10+2).
Use sector_div to support non power of 2 blocksize for the pool's
data device. This provides comparable performance to the power of 2
math that was performed until now (as tested on modern x86_64 hardware).
The kernel currently assumes that limits->discard_granularity is a power
of two so the thin target only enables discard support if the block
size is a power of two.
Eliminate pool structure's 'block_shift', 'offset_mask' and
remaining 4 byte holes.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
dm-stripe is usually used with a chunk size that is a power of two.
Use faster shifts and bit masks in such cases.
stripe_width is already optimized in a similar way.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
There is no technical limitation in device mapper that would prevent the
dm-stripe target from using a stripe size smaller than page size.
This patch removes the limit and makes stripe volumes portable across
architectures with different page size.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Support non-power-of-2 chunk sizes with dm striping for proper alignment
of stripe IO on storage that has non-power-of-2 optimal IO sizes (e.g.
RAID6 10+2).
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove the restriction that limits a target's specified maximum incoming
I/O size to be a power of 2.
Rename this setting from 'split_io' to the less-ambiguous 'max_io_len'.
Change it from sector_t to uint32_t, which is plenty big enough, and
introduce a wrapper function dm_set_target_max_io_len() to set it.
Use sector_div() to process it now that it is not necessarily a power of 2.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The structure stripe_c contains a stripes_mask field. This field is
useless because it can be trivially calculated by subtracting one from
stripes. It is used only at one place. This patch removes it.
The patch also changes ffs(stripes) - 1 to __ffs(stripes).
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
dm-stripe is supposed to ensure that all the space allocated to the
stripes is fully used and that all stripes are the same size. This
patch fixes the test. It checks that device length is divisible by the
chunk size and checks that the resulting quotient is divisible by the
number of stripes (which is equivalent to testing if device length is
divisible by chunk_size * stripes).
Previously, the code only tested that the number of sectors in the target
was divisible by each of the chunk size and the number of stripes
separately, which could leave entire stripes unused.
(A setup that genuinely needs some stripes to be shorter than others
can be created by concatenating striped targets.)
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Provide specific error message strings for two pool_ctr() failure cases
that currently give just "Unknown error".
Reference: test_two_pools_pointing_to_the_same_metadata_fails and
test_different_pool_cant_replace_pool in thinp-test-suite.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Introduce THIN_MAX_CONCURRENT_LOCKS into dm-thin-metadata to
give a name to an otherwise "magic" number.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove the pointless label 'out' from __commit_transaction in
dm-thin-metadata.c
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove debug space map checker from dm persistent data.
The space map checker is a wrapper for other space maps that double
checks the reference counts are correct. It holds all these reference
counts in memory rather than on disk, so uses a lot of memory and is
thus restricted to small pools.
As yet, this checker hasn't found any issues, but has caused a few of
its own due to people turning it on by default with larger pools.
Removing.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Clean up "warning: dubious: !x & y". Also make it clear that
__snapshotted_since() returns a bool and that dm_thin_lookup_result's
'shared' member is a flag.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Reduce the slab size used for the dm_thin_endio_hook mempool.
Allocation has been seen to fail on machines with smaller amounts
of memory due to fragmentation.
lvm: page allocation failure. order:5, mode:0xd0
device-mapper: table: 253:38: thin-pool: Error creating pool's endio_hook mempool
Cc: stable@vger.kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
- avoid a crash in dm-raid1 when discards coincide with mirror recovery;
- avoid discarding shared data that's still needed in dm-thin;
- don't guarantee that discarded blocks will be wiped in dm-raid1.
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Merge tag 'dm-3.5-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm
Pull device-mapper discard fixes from Alasdair G Kergon:
- avoid a crash in dm-raid1 when discards coincide with mirror
recovery;
- avoid discarding shared data that's still needed in dm-thin;
- don't guarantee that discarded blocks will be wiped in dm-raid1.
* tag 'dm-3.5-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm:
dm raid1: set discard_zeroes_data_unsupported
dm thin: do not send discards to shared blocks
dm raid1: fix crash with mirror recovery and discard
We can't guarantee that REQ_DISCARD on dm-mirror zeroes the data even if
the underlying disks support zero on discard. So this patch sets
ti->discard_zeroes_data_unsupported.
For example, if the mirror is in the process of resynchronizing, it may
happen that kcopyd reads a piece of data, then discard is sent on the
same area and then kcopyd writes the piece of data to another leg.
Consequently, the data is not zeroed.
The flag was made available by commit 983c7db347
(dm crypt: always disable discard_zeroes_data).
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
When process_discard receives a partial discard that doesn't cover a
full block, it sends this discard down to that block. Unfortunately, the
block can be shared and the discard would corrupt the other snapshots
sharing this block.
This patch detects block sharing and ends the discard with success when
sending it to the shared block.
The above change means that if the device supports discard it can't be
guaranteed that a discard request zeroes data. Therefore, we set
ti->discard_zeroes_data_unsupported.
Thin target discard support with this bug arrived in commit
104655fd4d (dm thin: support discards).
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch fixes a crash when a discard request is sent during mirror
recovery.
Firstly, some background. Generally, the following sequence happens during
mirror synchronization:
- function do_recovery is called
- do_recovery calls dm_rh_recovery_prepare
- dm_rh_recovery_prepare uses a semaphore to limit the number
simultaneously recovered regions (by default the semaphore value is 1,
so only one region at a time is recovered)
- dm_rh_recovery_prepare calls __rh_recovery_prepare,
__rh_recovery_prepare asks the log driver for the next region to
recover. Then, it sets the region state to DM_RH_RECOVERING. If there
are no pending I/Os on this region, the region is added to
quiesced_regions list. If there are pending I/Os, the region is not
added to any list. It is added to the quiesced_regions list later (by
dm_rh_dec function) when all I/Os finish.
- when the region is on quiesced_regions list, there are no I/Os in
flight on this region. The region is popped from the list in
dm_rh_recovery_start function. Then, a kcopyd job is started in the
recover function.
- when the kcopyd job finishes, recovery_complete is called. It calls
dm_rh_recovery_end. dm_rh_recovery_end adds the region to
recovered_regions or failed_recovered_regions list (depending on
whether the copy operation was successful or not).
The above mechanism assumes that if the region is in DM_RH_RECOVERING
state, no new I/Os are started on this region. When I/O is started,
dm_rh_inc_pending is called, which increases reg->pending count. When
I/O is finished, dm_rh_dec is called. It decreases reg->pending count.
If the count is zero and the region was in DM_RH_RECOVERING state,
dm_rh_dec adds it to the quiesced_regions list.
Consequently, if we call dm_rh_inc_pending/dm_rh_dec while the region is
in DM_RH_RECOVERING state, it could be added to quiesced_regions list
multiple times or it could be added to this list when kcopyd is copying
data (it is assumed that the region is not on any list while kcopyd does
its jobs). This results in memory corruption and crash.
There already exist bypasses for REQ_FLUSH requests: REQ_FLUSH requests
do not belong to any region, so they are always added to the sync list
in do_writes. dm_rh_inc_pending does not increase count for REQ_FLUSH
requests. In mirror_end_io, dm_rh_dec is never called for REQ_FLUSH
requests. These bypasses avoid the crash possibility described above.
These bypasses were improperly implemented for REQ_DISCARD when
the mirror target gained discard support in commit
5fc2ffeabb (dm raid1: support discard).
In do_writes, REQ_DISCARD requests is always added to the sync queue and
immediately dispatched (even if the region is in DM_RH_RECOVERING). However,
dm_rh_inc and dm_rh_dec is called for REQ_DISCARD resusts. So it violates the
rule that no I/Os are started on DM_RH_RECOVERING regions, and causes the list
corruption described above.
This patch changes it so that REQ_DISCARD requests follow the same path
as REQ_FLUSH. This avoids the crash.
Reference: https://bugzilla.redhat.com/837607
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Add a per-stripe lock to protect stripe specific data. The purpose is to reduce
lock contention of conf->device_lock.
stripe ->toread, ->towrite are protected by per-stripe lock. Accessing bio
list of the stripe is always serialized by this lock, so adding bio to the
lists (add_stripe_bio()) and removing bio from the lists (like
ops_run_biofill()) not race.
If bio in ->read, ->written ... list are not shared by multiple stripes, we
don't need any lock to protect ->read, ->written, because STRIPE_ACTIVE will
protect them. If the bio are shared, there are two protections:
1. bi_phys_segments acts as a reference count
2. traverse the list uses r5_next_bio, which makes traverse never access bio
not belonging to the stripe
Let's have an example:
| stripe1 | stripe2 | stripe3 |
...bio1......|bio2|bio3|....bio4.....
stripe2 has 4 bios, when it's finished, it will decrement bi_phys_segments for
all bios, but only end_bio for bio2 and bio3. bio1->bi_next still points to
bio2, but this doesn't matter. When stripe1 is finished, it will not touch bio2
because of r5_next_bio check. Next time stripe1 will end_bio for bio1 and
stripe3 will end_bio bio4.
before add_stripe_bio() addes a bio to a stripe, we already increament the bio
bi_phys_segments, so don't worry other stripes release the bio.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Neil pointed out the bitmap write optimization in handle_stripe_clean_event()
is unnecessary, because the chance one stripe gets written twice in the mean
time is rare. We can always do a bitmap_startwrite when a write request is
added to a stripe and bitmap_endwrite after write request is done. Delete the
optimization. With it, we can delete some cases of device_lock.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Raid5 overrides bio->bi_phys_segments, accessing it is with device_lock hold,
which is unnecessary, We can make it lockless actually.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
release_stripe() is a place conf->device_lock is heavily contended. We take the
lock even stripe count isn't 1, which isn't required.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
commit 4367af5561
md/raid1: clear bad-block record when write succeeds.
Added a 'reschedule_retry' call possibility at the end of
end_sync_write, but didn't add matching code at the end of
sync_request_write. So if the writes complete very quickly, or
scheduling makes it seem that way, then we can miss rescheduling
the request and the resync could hang.
Also commit 73d5c38a95
md: avoid races when stopping resync.
Fix a race condition in this same code in end_sync_write but didn't
make the change in sync_request_write.
This patch updates sync_request_write to fix both of those.
Patch is suitable for 3.1 and later kernels.
Reported-by: Alexander Lyakas <alex.bolshoy@gmail.com>
Original-version-by: Alexander Lyakas <alex.bolshoy@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
md will refuse to stop an array if any other fd (or mounted fs) is
using it.
When any fs is unmounted of when the last open fd is closed all
pending IO will be flushed (e.g. sync_blockdev call in __blkdev_put)
so there will be no pending IO to worry about when the array is
stopped.
However in order to send the STOP_ARRAY ioctl to stop the array one
must first get and open fd on the block device.
If some fd is being used to write to the block device and it is closed
after mdadm open the block device, but before mdadm issues the
STOP_ARRAY ioctl, then there will be no last-close on the md device so
__blkdev_put will not call sync_blockdev.
If this happens, then IO can still be in-flight while md tears down
the array and bad things can happen (use-after-free and subsequent
havoc).
So in the case where do_md_stop is being called from an open file
descriptor, call sync_block after taking the mutex to ensure there
will be no new openers.
This is needed when setting a read-write device to read-only too.
Cc: stable@vger.kernel.org
Reported-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
commit c6563a8c38
md: add possibility to change data-offset for devices.
introduced a 'new_data_offset' attribute which should normally
be the same as 'data_offset', but can be explicitly set to a different
value to allow a reshape operation to move the data.
Unfortunately when the 'data_offset' is explicitly set through
sysfs, the new_data_offset is not also set, so the two would become
out-of-sync incorrectly.
One result of this is that trying to set the 'size' after the
'data_offset' would fail because it is not permitted to set the size
when the 'data_offset' and 'new_data_offset' are different - as that
can be confusing.
Consequently when mdadm tried to do this while assembling an IMSM
array it would fail.
This bug was introduced in 3.5-rc1.
Reported-by: Brian Downing <bdowning@lavos.net>
Bisected-by: Brian Downing <bdowning@lavos.net>
Tested-by: Brian Downing <bdowning@lavos.net>
Signed-off-by: NeilBrown <neilb@suse.de>
This bug has been present ever since data-check was introduce
in 2.6.16. However it would only fire if a data-check were
done on a degraded array, which was only possible if the array
has 3 or more devices. This is certainly possible, but is quite
uncommon.
Since hot-replace was added in 3.3 it can happen more often as
the same condition can arise if not all possible replacements are
present.
The problem is that as soon as we submit the last read request, the
'r1_bio' structure could be freed at any time, so we really should
stop looking at it. If the last device is being read from we will
stop looking at it. However if the last device is not due to be read
from, we will still check the bio pointer in the r1_bio, but the
r1_bio might already be free.
So use the read_targets counter to make sure we stop looking for bios
to submit as soon as we have submitted them all.
This fix is suitable for any -stable kernel since 2.6.16.
Cc: stable@vger.kernel.org
Reported-by: Arnold Schulz <arnysch@gmx.net>
Signed-off-by: NeilBrown <neilb@suse.de>
I really shouldn't do important things late in the day. It seems
that I get careless.
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Merge tag 'md-3.5-fixes' of git://neil.brown.name/md
Pull raid10 build failure fix from NeilBrown:
"I really shouldn't do important things late in the day. It seems that
I get careless."
* tag 'md-3.5-fixes' of git://neil.brown.name/md:
md/raid10: fix careless build error
build error introduced by commit b357f04a67
That function doesn't get extra args until a later patch. Bother.
Reported-by: Fengguang Wu <wfg@linux.intel.com>
Reported-by: Simon Kirby <sim@hostway.ca>
Reported-by: Tobias Klausmann <tobias.johannes.klausmann@mni.thm.de>
Signed-off-by: NeilBrown <neilb@suse.de>
If CONFIG_DM_DEBUG_SPACE_MAPS is enabled and memory is fragmented and a
sufficiently-large metadata device is used in a thin pool then the space
map checker will fail to allocate the memory it requires.
Switch from kmalloc to vmalloc to allow larger virtually contiguous
allocations for the space map checker's internal count arrays.
Reported-by: Vivek Goyal <vgoyal@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
If CONFIG_DM_DEBUG_SPACE_MAPS is enabled and dm_sm_checker_create()
fails, dm_tm_create_internal() would still return success even though it
cleaned up all resources it was supposed to have created. This will
lead to a kernel crash:
general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC
...
RIP: 0010:[<ffffffff81593659>] [<ffffffff81593659>] dm_bufio_get_block_size+0x9/0x20
Call Trace:
[<ffffffff81599bae>] dm_bm_block_size+0xe/0x10
[<ffffffff8159b8b8>] sm_ll_init+0x78/0xd0
[<ffffffff8159c1a6>] sm_ll_new_disk+0x16/0xa0
[<ffffffff8159c98e>] dm_sm_disk_create+0xfe/0x160
[<ffffffff815abf6e>] dm_pool_metadata_open+0x16e/0x6a0
[<ffffffff815aa010>] pool_ctr+0x3f0/0x900
[<ffffffff8158d565>] dm_table_add_target+0x195/0x450
[<ffffffff815904c4>] table_load+0xe4/0x330
[<ffffffff815917ea>] ctl_ioctl+0x15a/0x2c0
[<ffffffff81591963>] dm_ctl_ioctl+0x13/0x20
[<ffffffff8116a4f8>] do_vfs_ioctl+0x98/0x560
[<ffffffff8116aa51>] sys_ioctl+0x91/0xa0
[<ffffffff81869f52>] system_call_fastpath+0x16/0x1b
Fix the space map checker code to return an appropriate ERR_PTR and have
dm_sm_disk_create() and dm_tm_create_internal() check for it with
IS_ERR.
Reported-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cleanup the shadow table before destroying the transaction manager.
Reference: leak was identified with kmemleak when running
test_discard_random_sectors in the thinp-test-suite.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Userland sometimes sees a corrupt metadata block if metadata is changing
rapidly when a metadata snapshot is reserved for userland, To make the
problem go away, commit before we take the metadata snapshot (which is a
sensible thing to do anyway).
The checksums mean userland spots this corruption immediately so there's
no risk of acting on incorrect data. No corruption exists from the
kernel's point of view, and thin_check passes after pool shutdown.
I believe this is to do with shared blocks at the first level of the
{device, mapping} btree. Prior to the metadata-snap support no sharing
at this level was possible, so this patch is only required after commit
cc8394d86f ("dm thin: provide userspace
access to pool metadata").
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The value returned by "mddev_check_plug" is only valid until the
next 'schedule' as that will unplug things. This could happen at any
call to mempool_alloc.
So just calling mddev_check_plug at the start doesn't really make
sense.
So call it just before, or just after, queuing things for the thread.
As the action that happens at unplug is to wake the thread, this makes
lots of sense.
If we cannot add a plug (which requires a small GFP_ATOMIC alloc) we
wake thread immediately.
RAID5 is a bit different. Requests are queued for the thread and the
thread is woken by release_stripe. So we don't need to wake the
thread on failure.
However the thread doesn't perform certain actions when there is any
active plug, so it is important to install a plug before waking the
thread. So for RAID5 we install the plug *before* queuing the request
and waking the thread.
Without this patch it is possible for raid1 or raid10 to queue a
request without then waking the thread, resulting in the array locking
up.
Also change raid10 to only flush_pending_write when there are not
active plugs, just like raid1.
This patch is suitable for 3.0 or later. I plan to submit it to
-stable, but I'll like to let it spend a few weeks in mainline
first to be sure it is completely safe.
Signed-off-by: NeilBrown <neilb@suse.de>
We currently only allow a device to be re-added if it appear to be
in-sync. This is overly restrictive as it may be desirable to re-add
a device that is in the middle of recovery.
So remove the test for "InSync" - the test on rdev->raid_disk is
sufficient to ensure that the re-add will succeed.
Reported-by: Alexander Lyakas <alex.bolshoy@gmail.com>
Tested-by: Alexander Lyakas <alex.bolshoy@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
When we added hot_replace we doubled the number of devices
that could be in a RAID1 array. So we doubled how far read_balance
would search. Unfortunately we didn't double the point at which
it looped back to the beginning - so it effectively loops over
all non-replacement disks twice.
This doesn't cause bad behaviour, but it pointless and means we
never read from replacement devices.
Signed-off-by: NeilBrown <neilb@suse.de>
There isn't locking setting STRIPE_DELAYED and STRIPE_PREREAD_ACTIVE bits, but
the two bits have relationship. A delayed stripe can be moved to hold list only
when preread active stripe count is below IO_THRESHOLD. If a stripe has both
the bits set, such stripe will be in delayed list and preread count not 0,
which will make such stripe never leave delayed list.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
We may not be able to fix a bad block if:
- the array is degraded
- the over-write fails.
In these cases we currently eject the device, but we should
record a bad block if possible.
Signed-off-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Having the 'name' arg optional and defaulting to the current
personality name is no necessary and leads to errors, as when
changing the level of an array we can end up using the
name of the old level instead of the new one.
So make it non-optional and always explicitly pass the name
of the level that the array will be.
Reported-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
commit 58c54fcca3
md/raid10: handle further errors during fix_read_error better.
in 3.1 added "r10_sync_page_io" which takes an IO size in sectors.
But we were passing the IO size in bytes!!!
This resulting in bio_add_page failing, and empty request being sent
down, and a consequent BUG_ON in scsi_lib.
[fix missing space in error message at same time]
This fix is suitable for 3.1.y and later.
Cc: stable@vger.kernel.org
Reported-by: Christian Balzer <chibi@gol.com>
Signed-off-by: NeilBrown <neilb@suse.de>
commit 43220aa0f2
md/raid5: fix a hang on device failure.
fixed a hang, but introduced a refcounting in-balance so
that if the presence of bad-blocks ever caused an rdev to
be 'blocked' we would increment the refcount on the rdev and
never decrement it.
So added the needed rdev_dec_pending when md_wait_for_blocked_rdev
is not called.
Reported-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
In ops_run_io(), the call to md_wait_for_blocked_rdev will decrement
nr_pending so we lose the reference we hold on the rdev.
So atomic_inc it first to maintain the reference.
This bug was introduced by commit 73e92e51b7
md/raid5. Don't write to known bad block on doubtful devices.
which appeared in 3.0, so patch is suitable for stable kernels since
then.
Cc: stable@vger.kernel.org
Signed-off-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
In chunk_aligned_read() we are adding data_offset before calling
is_badblock. But is_badblock also adds data_offset, so that is bad.
So move the addition of data_offset to after the call to
is_badblock.
This bug was introduced by commit 31c176ecdf
md/raid5: avoid reading from known bad blocks.
which first appeared in 3.0. So that patch is suitable for any
-stable kernel from 3.0.y onwards. However it will need minor
revision for most of those (as the comment didn't appear until
recently).
Cc: stable@vger.kernel.org
Signed-off-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
If a RAID5 has both a failed device and a device marked as
'WantReplacement', then we should preferentially replace the failed
device.
However the current code replaces whichever is found first.
So split into 2 loops, check fail failed/missing first, and only check
for WantReplacement if nothing is failed or missing.
Reported-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
If a RAID10 has an odd number of chunks - as might happen when there
are an odd number of devices - the last chunk has no pair and so is
not mirrored. We don't store data there, but when recovering the last
device in an array we retry to recover that last chunk from a
non-existent location. This results in an error, and the recovery
aborts.
When we get to that last chunk we should just stop - there is nothing
more to do anyway.
This bug has been present since the introduction of RAID10, so the
patch is appropriate for any -stable kernel.
Cc: stable@vger.kernel.org
Reported-by: Christian Balzer <chibi@gol.com>
Tested-by: Christian Balzer <chibi@gol.com>
Signed-off-by: NeilBrown <neilb@suse.de>
One sparse-warning fix, one bigfix for 3.4-stable
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Merge tag 'md-3.5-fixes' of git://neil.brown.name/md
Pull two md fixes from NeilBrown:
"One sparse-warning fix, one bugfix for 3.4-stable"
* tag 'md-3.5-fixes' of git://neil.brown.name/md:
md: raid1/raid10: fix problem with merge_bvec_fn
lib/raid6: fix sparse warnings in recovery functions
and provide a simple reserve/release mechanism for userspace tools to
access thin provisioning metadata while the pool is in use.
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Merge tag 'dm-3.5-changes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm
Pull device-mapper updates from Alasdair G Kergon:
"Improve multipath's retrying mechanism in some defined circumstances
and provide a simple reserve/release mechanism for userspace tools to
access thin provisioning metadata while the pool is in use."
* tag 'dm-3.5-changes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm:
dm thin: provide userspace access to pool metadata
dm thin: use slab mempools
dm mpath: allow ioctls to trigger pg init
dm mpath: delay retry of bypassed pg
dm mpath: reduce size of struct multipath
This patch implements two new messages that can be sent to the thin
pool target allowing it to take a snapshot of the _metadata_. This,
read-only snapshot can be accessed by userland, concurrently with the
live target.
Only one metadata snapshot can be held at a time. The pool's status
line will give the block location for the current msnap.
Since version 0.1.5 of the userland thin provisioning tools, the
thin_dump program displays the msnap as follows:
thin_dump -m <msnap root> <metadata dev>
Available here: https://github.com/jthornber/thin-provisioning-tools
Now that userland can access the metadata we can do various things
that have traditionally been kernel side tasks:
i) Incremental backups.
By using metadata snapshots we can work out what blocks have
changed over time. Combined with data snapshots we can ensure
the data doesn't change while we back it up.
A short proof of concept script can be found here:
https://github.com/jthornber/thinp-test-suite/blob/master/incremental_backup_example.rb
ii) Migration of thin devices from one pool to another.
iii) Merging snapshots back into an external origin.
iv) Asyncronous replication.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Use dedicated caches prefixed with a "dm_" name rather than relying on
kmalloc mempools backed by generic slab caches so the memory usage of
thin provisioning (and any leaks) can be accounted for independently.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
After the failure of a group of paths, any alternative paths that
need initialising do not become available until further I/O is sent to
the device. Until this has happened, ioctls return -EAGAIN.
With this patch, new paths are made available in response to an ioctl
too. The processing of the ioctl gets delayed until this has happened.
Instead of returning an error, we submit a work item to kmultipathd
(that will potentially activate the new path) and retry in ten
milliseconds.
Note that the patch doesn't retry an ioctl if the ioctl itself fails due
to a path failure. Such retries should be handled intelligently by the
code that generated the ioctl in the first place, noting that some SCSI
commands should not be retried because they are not idempotent (XOR write
commands). For commands that could be retried, there is a danger that
if the device rejected the SCSI command, the path could be errorneously
marked as failed, and the request would be retried on another path which
might fail too. It can be determined if the failure happens on the
device or on the SCSI controller, but there is no guarantee that all
SCSI drivers set these flags correctly.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
If I/O needs retrying and only bypassed priority groups are available,
set the pg_init_delay_retry flag to wait before retrying.
If, for example, the reason for the bypass is that the controller is
getting reset or there is a firmware upgrade happening, retrying right
away would cause a flood of log messages and retries for what could be a
few seconds or even several minutes.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Move multipath structure's 'lock' and 'queue_size' members to eliminate
two 4-byte holes. Also use a bit within a single unsigned int for each
existing flag (saves 8-bytes). This allows future flags to be added
without each consuming an unsigned int.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The new merge_bvec_fn which calls the corresponding function
in subsidiary devices requires that mddev->merge_check_needed
be set if any child has a merge_bvec_fn.
However were were only setting that when a device was hot-added,
not when a device was present from the start.
This bug was introduced in 3.4 so patch is suitable for 3.4.y
kernels. However that are conflicts in raid10.c so a separate
patch will be needed for 3.4.y.
Cc: stable@vger.kernel.org
Reported-by: Sebastian Riemer <sebastian.riemer@profitbricks.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Main features:
- RAID10 arrays can be reshapes - adding and removing devices and
changing chunks (not 'far' array though)
- allow RAID5 arrays to be reshaped with a backup file (not tested
yet, but the priciple works fine for RAID10).
- arrays can be reshaped while a bitmap is present - you no longer
need to remove it first
- SSSE3 support for RAID6 syndrome calculations
and of course a number of minor fixes etc.
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Merge tag 'md-3.5' of git://neil.brown.name/md
Pull md updates from NeilBrown:
"It's been a busy cycle for md - lots of fun stuff here.. if you like
this kind of thing :-)
Main features:
- RAID10 arrays can be reshaped - adding and removing devices and
changing chunks (not 'far' array though)
- allow RAID5 arrays to be reshaped with a backup file (not tested
yet, but the priciple works fine for RAID10).
- arrays can be reshaped while a bitmap is present - you no longer
need to remove it first
- SSSE3 support for RAID6 syndrome calculations
and of course a number of minor fixes etc."
* tag 'md-3.5' of git://neil.brown.name/md: (56 commits)
md/bitmap: record the space available for the bitmap in the superblock.
md/raid10: Remove extras after reshape to smaller number of devices.
md/raid5: improve removal of extra devices after reshape.
md: check the return of mddev_find()
MD RAID1: Further conditionalize 'fullsync'
DM RAID: Use md_error() in place of simply setting Faulty bit
DM RAID: Record and handle missing devices
DM RAID: Set recovery flags on resume
md/raid5: Allow reshape while a bitmap is present.
md/raid10: resize bitmap when required during reshape.
md: allow array to be resized while bitmap is present.
md/bitmap: make sure reshape request are reflected in superblock.
md/bitmap: add bitmap_resize function to allow bitmap resizing.
md/bitmap: use DIV_ROUND_UP instead of open-code
md/bitmap: create a 'struct bitmap_counts' substructure of 'struct bitmap'
md/bitmap: make bitmap bitops atomic.
md/bitmap: make _page_attr bitops atomic.
md/bitmap: merge bitmap_file_unmap and bitmap_file_put.
md/bitmap: remove async freeing of bitmap file.
md/bitmap: convert some spin_lock_irqsave to spin_lock_irq
...
Now that bitmaps can grow and shrink it is best if we record
how much space is available. This means that when
we reduce the size of the bitmap we won't "lose" the space
for late when we might want to increase the size of the bitmap
again.
Signed-off-by: NeilBrown <neilb@suse.de>
When a reshape which reduced the number of devices finishes
we must remove the extra devices.
So ensure that raid10_remove_disk won't try to keep them, and
have raid10_finish_reshape clear the 'in_sync' flag. Then
remove_and_add_spares will be able to remove them.
Reported-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: NeilBrown <neilb@suse.de>
After a reshape which reduced the number of devices we need
to disconnect the extra devices.
The code for this doesn't currently handle 'replacement' devices.
It is very unlikely that such devices will be present, but it is
safest to handle them anyway.
So simplify the handling. Just clear In_sync and leave it
to remove_and_add_spaces (which will be called soon) to do
the real works.
Signed-off-by: NeilBrown <neilb@suse.de>
Check the return of mddev_find(), since it may fail due to out of
memeory or out of usable minor number.
The reason I chose -ENODEV instead of -ENOMEM or something else is
md_alloc() function chose that ;)
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
A RAID1 device does not necessarily need a fullsync if the bitmap can be used instead.
Similar to commit d6b212f4b1 in raid5.c, if a raid1
device can be brought back (i.e. from a transient failure) it shouldn't need a
complete resync. Provided the bitmap is not to old, it will have recorded the areas
of the disk that need recovery.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
When encountering an error while reading the superblock, call md_error.
We are currently setting the 'Faulty' bit on one of the array devices when an
error is encountered while reading the superblock of a dm-raid array. We should
be calling md_error(), as it handles the error more completely.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Missing dm-raid devices should be recorded in the superblock
When specifying the devices that compose a DM RAID array, it is possible to denote
failed or missing devices with '-'s. When this occurs, we must record this in the
superblock. We do this by checking if the array position's data device is missing
and then forcing MD to record the superblock by setting 'MD_CHANGE_DEVS' in
'raid_resume'. If we do not cause the superblock to be rewritten by the resume
function, it is possible for a stale superblock to be written by an out-going
in-active table (during 'raid_dtr').
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Properly initialize MD recovery flags when resuming device-mapper devices.
When a device-mapper device is suspended, all I/O must stop. This is done by
calling 'md_stop_writes' and 'mddev_suspend'. These calls in-turn manipulate
the recovery flags - including setting 'MD_RECOVERY_FROZEN'. The DM device
may have been suspended while recovery was not yet complete, so the process
needs to pick-up where it left off. Since 'mddev_resume' does not unset
'MD_RECOVERY_FROZEN' and set 'MD_RECOVERY_NEEDED', we must do it ourselves.
'MD_RECOVERY_NEEDED' can safely be set in 'mddev_resume', but 'MD_RECOVERY_FROZEN'
must be set outside of 'mddev_resume' due to how MD handles RAID reshaping.
(e.g. It is possible for a user to delay reshaping a RAID5->RAID6 by purposefully
setting 'MD_RECOVERY_FROZEN'. Clearing it in 'mddev_resume' would override the
desired behavior.)
Because 'mddev_resume' already unconditionally calls 'md_wakeup_thread(mddev->thread)'
there is no need to make this call from 'raid_resume' since it calls 'mddev_resume'.
Also clean up where level_store calls mddev_resume() - it current
duplicates some of the funcitons of that call. - NB
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
We always should have allowed this. A raid5 reshape doesn't change
the size of the bitmap, so not need to restrict it.
Also add a test to make sure we don't try to start a reshape on a
failed array.
Signed-off-by: NeilBrown <neilb@suse.de>
Now that bitmaps can be resized, we can allow an array to be resized
while the bitmap is present.
This only covers resizing that involves changing the effective size
of member devices, not resizing that changes the number of devices.
Signed-off-by: NeilBrown <neilb@suse.de>
As a reshape may change the sync_size and/or chunk_size, we need
to update these whenever we write out the bitmap superblock.
Signed-off-by: NeilBrown <neilb@suse.de>
This function will allocate the new data structures and copy
bits across from old to new, allowing for the possibility that the
chunksize has changed.
Use the same function for performing the initial allocation
of the structures. This improves test coverage.
When bitmap_resize is used to resize an existing bitmap, it
only copies '1' bits in, not '0' bits.
So when allocating the bitmap, ensure everything is initialised
to ZERO.
Signed-off-by: NeilBrown <neilb@suse.de>
The new "struct bitmap_counts" contains all the fields that are
related to counting the number of active writes in each bitmap chunk.
Having this separate will make it easier to change the chunksize
or overall size of a bitmap atomically.
Signed-off-by: NeilBrown <neilb@suse.de>
Using e.g. set_bit instead of __set_bit and using test_and_clear_bit
allow us to remove some locking and contract other locked ranges.
It is rare that we set or clear a lot of these bits, so gain should
outweigh any cost.
Signed-off-by: NeilBrown <neilb@suse.de>
There functions really do one thing together: release the
'bitmap_storage'. So make them just one function.
Since we removed the locking (previous patch), we don't need to zero
any fields before freeing them, so it all becomes a bit simpler.
Signed-off-by: NeilBrown <neilb@suse.de>
There is no real value in freeing things the moment there is an error.
It is just as good to free the bitmap file and pages when the bitmap
is explicitly removed (and replaced?) or at shutdown.
With this gone, the bitmap will only disappear when the array is
quiescent, so we can remove some locking.
As the 'filemap' doesn't disappear now, include extra checks before
trying to write any of it out.
Also remove the check for "has it disappeared" in
bitmap_daemon_write().
Signed-off-by: NeilBrown <neilb@suse.de>
All of these sites can only be called from process context with
irqs enabled, so using irqsave/irqrestore just adds noise.
Remove it.
Signed-off-by: NeilBrown <neilb@suse.de>
We currently use '&' and '|' which isn't the norm in the kernel
and doesn't allow easy atomicity.
So change to bit numbers and {set,clear,test}_bit.
This allows us to remove a spinlock/unlock (which was dubious anyway)
and some other simplifications.
Signed-off-by: NeilBrown <neilb@suse.de>
Just do single-bit manipulations on bitmap->flags and copy whole
value between that and sb->state.
This will allow next patch which changes how bit manipulations are
performed on bitmap->flags.
This does result in BITMAP_STALE not being set in sb by
bitmap_read_sb, however as the setting is determined by other
information in the 'sb' we do not lose information this way.
Normally, bitmap_load will be called shortly which will clear
BITMAP_STALE anyway.
Signed-off-by: NeilBrown <neilb@suse.de>
This function isn't really needed. It sets or clears a flag in both
bitmap->flags and sb->state.
However both times it is called, bitmap_update_sb is called soon
afterwards which copies bitmap->flags to sb->state.
So just make changes to bitmap->flags, and open-code those rather than
hiding in a function.
Signed-off-by: NeilBrown <neilb@suse.de>
This new 'struct bitmap_storage' reflects the external storage of the
bitmap.
Having this clearly defined will make it easier to change the storage
used while the array is active.
Signed-off-by: NeilBrown <neilb@suse.de>
Most often we have the page number, not the page. And that is what
the *_page_attr() functions really want. So change the arguments to
take that number.
Signed-off-by: NeilBrown <neilb@suse.de>
Instead of allocating pages in read_sb_page, read_page and
bitmap_read_sb, allocate them all in bitmap_init_from disk.
Also replace the hack of calling "attach_page_buffers(page, NULL)" to
ensure that free_buffer() won't complain, by putting a test for
PagePrivate in free_buffer().
Signed-off-by: NeilBrown <neilb@suse.de>
An md bitmap comprises two parts
- internal counting of active writes per 'chunk'.
- external storage of whether there are any active writes on
each chunk
The second requires the first, but the first doesn't require the
second.
Not having backing storage means that the bitmap cannot expedite
resync after a crash, but it still allows us to expedite the recovery
of a recently-removed device.
So: allow a bitmap to exist even if there is no backing device.
In that case we default to 128M chunks.
A particular value of this is that we can remove and re-add a bitmap
(possibly of a different granularity) on a degraded array, and not
lose the information needed to fast-recover the missing device.
We don't actually activate these bitmaps yet - that will come
in a later patch.
Signed-off-by: NeilBrown <neilb@suse.de>
If we are to allow bitmaps to be resized when the array is resized,
we need to know how much space there is.
So create an attribute to store this information and set appropriate
defaults.
It can be set more precisely via sysfs, or future metadata extensions
may allow it to be recorded.
Signed-off-by: NeilBrown <neilb@suse.de>
There are two different 'pending' concepts in the handling of the
write intent bitmap.
Firstly, a 'page' from the bitmap (which container PAGE_SIZE*8 bits)
may have changes (bits cleared) that should be written in due course.
There is no hurry for these and the page will transition from
PENDING to NEEDWRITE and will then be written, though if it ever
becomes DIRTY it will be written much sooner and PENDING will be
cleared.
Secondly, a page of counters - which contains PAGE_SIZE/2 counters, one
for each bit, can usefully have a 'pending' flag which indicates if
any of the counters are low (2 or 1) and ready to be processed by
bitmap_daemon_work(). If this flag is clear we can skip the whole
page.
These two concepts are currently combined in the bitmap-file flag.
This causes a tighter connection between the counters and the bitmap
file than I would like - as I want to add some flexibility to the
bitmap file.
So introduce a new flag with the page-of-counters, and rewrite
bitmap_daemon_work() so that it handles the two different 'pending'
concepts separately.
This also allows us to clear BITMAP_PAGE_PENDING when we write out
a dirty page, which may occasionally reduce the number of times we
write a page.
Signed-off-by: NeilBrown <neilb@suse.de>
REQ_SYNC is ignored in current raid5 code. Block layer does use it to do
policy,
for example ioscheduler. This patch adds it.
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
If the allocation of rep1_bio fails, we currently don't free the 'bio'
of the same dev.
Reported by kmemleak.
Signed-off-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
When attempting to fix a read error, it is acceptable to read from a
device that is recovering, provided the recovery has got past the
place we are reading from. This makes the test for "can we read from
here" the same as the test in read_balance.
Signed-off-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
This ensures that it is always freed - there were case where
we failed to free the page.
Reported-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
dm-raid currently open-codes the freeing of some members of
and rdev. It is more maintainable to have it call common code
from md.c which does this for all call-sites.
So remove free_disk_sb to md_rdev_clear, export it, and use it in
dm-raid.c
Signed-off-by: NeilBrown <neilb@suse.de>
A 'near' or 'offset' lay RAID10 array can be reshaped to a different
'near' or 'offset' layout, a different chunk size, and a different
number of devices.
However the number of copies cannot change.
Unlike RAID5/6, we do not support having user-space backup data that
is being relocated during a 'critical section'. Rather, the
data_offset of each device must change so that when writing any block
to a new location, it will not over-write any data that is still
'live'.
This means that RAID10 reshape is not supportable on v0.90 metadata.
The different between the old data_offset and the new_offset must be
at least the larger of the chunksize multiplied by offset copies of
each of the old and new layout. (for 'near' mode, offset_copies == 1).
A larger difference of around 64M seems useful for in-place reshapes
as more data can be moved between metadata updates.
Very large differences (e.g. 512M) seem to slow the process down due
to lots of long seeks (on oldish consumer graded devices at least).
Metadata needs to be updated whenever the place we are about to write
to is considered - by the current metadata - to still contain data in
the old layout.
[unbalanced locking fix from Dan Carpenter <dan.carpenter@oracle.com>]
Signed-off-by: NeilBrown <neilb@suse.de>
We will soon be interpreting the layout (and chunksize etc) from
multiple places to support reshape. So split it out into separate
function.
Signed-off-by: NeilBrown <neilb@suse.de>
When RAID10 supports reshape it will need a 'previous' and a 'current'
geometry, so introduce that here.
Use the 'prev' geometry when before the reshape_position, and the
current 'geo' when beyond it. At other times, use both as
appropriate.
For now, both are identical (And reshape_position is never set).
When we use the 'prev' geometry, we must use the old data_offset.
When we use the current (And a reshape is happening) we must use
the new_data_offset.
Signed-off-by: NeilBrown <neilb@suse.de>
Some resync type operations need to act on the address space of the
device, others on the address space of the array.
This only affects RAID10, so it sets resync_max_sectors to the array
size (it defaults to the device size), and that is currently used for
resync only. However reshape of a RAID10 must be done against the
array size, not device size, so change code to use resync_max_sectors
for both the resync and the reshape cases.
This does not affect RAID5 or RAID1, just RAID10.
Signed-off-by: NeilBrown <neilb@suse.de>
Some code in raid1 and raid10 use sync_page_io to
read/write pages when responding to read errors.
As we will shortly support changing data_offset for
raid10, this function must understand new_data_offset.
So add that understanding.
Signed-off-by: NeilBrown <neilb@suse.de>
We will shortly be adding reshape support for RAID10 which will
require it having 2 concurrent geometries (before and after).
To make that easier, collect most geometry fields into 'struct geom'
and access them from there. Then we will more easily be able to add
a second set of fields.
Note that 'copies' is not in this struct and so cannot be changed.
There is little need to change this number and doing so is a lot
more difficult as it requires reallocating more things.
So leave it out for now.
Signed-off-by: NeilBrown <neilb@suse.de>
The important issue here is incorporating the different in data_offset
into calculations concerning when we might need to over-write data
that is still thought to be valid.
To this end we find the minimum offset difference across all devices
and add that where appropriate.
Signed-off-by: NeilBrown <neilb@suse.de>
As there can now be two different data_offsets - an 'old' and
a 'new' - we need to carefully choose between them.
Signed-off-by: NeilBrown <neilb@suse.de>
When reshaping we can avoid costly intermediate backup by
changing the 'start' address of the array on the device
(if there is enough room).
So as a first step, allow such a change to be requested
through sysfs, and recorded in v1.x metadata.
(As we didn't previous check that all 'pad' fields were zero,
we need a new FEATURE flag for this.
A (belatedly) check that all remaining 'pad' fields are
zero to avoid a repeat of this)
The new data offset must be requested separately for each device.
This allows each to have a different change in the data offset.
This is not likely to be used often but as data_offset can be
set per-device, new_data_offset should be too.
This patch also removes the 'acknowledged' arg to rdev_set_badblocks as
it is never used and never will be. At the same time we add a new
arg ('in_new') which is currently always zero but will be used more
soon.
When a reshape finishes we will need to update the data_offset
and rdev->sectors. So provide an exported function to do that.
Signed-off-by: NeilBrown <neilb@suse.de>
Currently a reshape operation always progresses from the start
of the array to the end unless the number of devices is being
reduced, in which case it progressed in the opposite direction.
To reverse a partial reshape which changes the number of devices
you can stop the array and re-assemble with the raid-disks numbers
reversed and it will undo.
However for a reshape that does not change the number of devices
it is not possible to reverse the reshape in the middle - you have to
wait until it completes.
So add a 'reshape_direction' attribute with is either 'forwards' or
'backwards' and can be explicitly set when delta_disks is zero.
This will become more important when we allow the data_offset to
change in a reshape. Then the explicit statement of what direction is
being used will be more useful.
This can be enabled in raid5 trivially as it already supports
reverse reshape and just needs to use a different trigger to request it.
Signed-off-by: NeilBrown <neilb@suse.de>
A flush request is usually issued in transaction commit code path, so
using GFP_KERNEL to allocate memory for flush request bio falls into
the classic deadlock issue.
This is suitable for any -stable kernel to which it applies as it
avoids a possible deadlock.
Cc: stable@vger.kernel.org
Signed-off-by: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
When the thin pool target clears the discard_passdown parameter
internally, it incorrectly changes the table line reported to userspace.
This breaks dumb string comparisons on these table lines in generic
userspace device-mapper library code and leads to tables being reloaded
repeatedly when nothing is actually meant to be changing.
This patch corrects this by no longer changing the table line when
discard passdown was disabled.
We can still tell when discard passdown is overridden by looking for the
message "Discard unsupported by data device (sdX): Disabling discard passdown."
This automatic detection is also moved from the 'load' to the 'resume'
so that it is re-evaluated should the properties of underlying devices
change.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Without this patch, recovery will crash
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Merge tag 'md-3.4-fixes' of git://neil.brown.name/md
Pull one more md bugfix from NeilBrown:
"Fix bug in recent fix to RAID10.
Without this patch, recovery will crash"
* tag 'md-3.4-fixes' of git://neil.brown.name/md:
md/raid10: fix transcription error in calc_sectors conversion.
The old code was
sector_div(stride, fc);
the new code was
sector_dir(size, conf->near_copies);
'size' is right (the stride various wasn't really needed), but
'fc' means 'far_copies', and that is an important difference.
Signed-off-by: NeilBrown <neilb@suse.de>
one fixes a bug in the new raid10 resize code so is relevant
to 3.4 only
Other fixes a bug in the use of md by dm-raid, so is relevant
to any kernel with dm-raid support
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Merge tag 'md-3.4-fixes' of git://neil.brown.name/md
Pull two md fixes from NeilBrown:
"One fixes a bug in the new raid10 resize code so is relevant to 3.4
only.
The other fixes a bug in the use of md by dm-raid, so is relevant to
any kernel with dm-raid support"
* tag 'md-3.4-fixes' of git://neil.brown.name/md:
MD: Add del_timer_sync to mddev_suspend (fix nasty panic)
md/raid10: set dev_sectors properly when resizing devices in array.
Use del_timer_sync to remove timer before mddev_suspend finishes.
We don't want a timer going off after an mddev_suspend is called. This is
especially true with device-mapper, since it can call the destructor function
immediately following a suspend. This results in the removal (kfree) of the
structures upon which the timer depends - resulting in a very ugly panic.
Therefore, we add a del_timer_sync to mddev_suspend to prevent this.
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
raid10 stores dev_sectors in 'conf' separately from the one in
'mddev' because it can have a very significant effect on block
addressing and so need to be updated carefully.
However raid10_resize isn't updating it at all!
To update it correctly, we need to make sure it is a proper
multiple of the chunksize taking various details of the layout
in to account.
This calculation is currently done in setup_conf. So split it
out from there and call it from raid10_resize as well.
Then set conf->dev_sectors properly.
Signed-off-by: NeilBrown <neilb@suse.de>
Pull networking fixes from David S. Miller:
1) Since we do RCU lookups on ipv4 FIB entries, we have to test if the
entry is dead before returning it to our caller.
2) openvswitch locking and packet validation fixes from Ansis Atteka,
Jesse Gross, and Pravin B Shelar.
3) Fix PM resume locking in IGB driver, from Benjamin Poirier.
4) Fix VLAN header handling in vhost-net and macvtap, from Basil Gor.
5) Revert a bogus network namespace isolation change that was causing
regressions on S390 networking devices.
6) If bonding decides to process and handle a LACPDU frame, we
shouldn't bump the rx_dropped counter. From Jiri Bohac.
7) Fix mis-calculation of available TX space in r8169 driver when doing
TSO, which can lead to crashes and/or hung device. From Julien
Ducourthial.
8) SCTP does not validate cached routes properly in all cases, from
Nicolas Dichtel.
9) Link status interrupt needs to be handled in ks8851 driver, from
Stephen Boyd.
10) Use capable(), not cap_raised(), in connector/userns netlink code.
From Eric W. Biederman via Andrew Morton.
11) Fix pktgen OOPS on module unload, from Eric Dumazet.
12) iwlwifi under-estimates SKB truesizes, also from Eric Dumazet.
13) Cure division by zero in SFC driver, from Ben Hutchings.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (26 commits)
ks8851: Update link status during link change interrupt
macvtap: restore vlan header on user read
vhost-net: fix handle_rx buffer size
bonding: don't increase rx_dropped after processing LACPDUs
connector/userns: replace netlink uses of cap_raised() with capable()
sctp: check cached dst before using it
pktgen: fix crash at module unload
Revert "net: maintain namespace isolation between vlan and real device"
ehea: fix losing of NEQ events when one event occurred early
igb: fix rtnl race in PM resume path
ipv4: Do not use dead fib_info entries.
r8169: fix unsigned int wraparound with TSO
sfc: Fix division by zero when using one RX channel and no SR-IOV
openvswitch: Validation of IPv6 set port action uses IPv4 header
net: compare_ether_addr[_64bits]() has no ordering
cdc_ether: Ignore bogus union descriptor for RNDIS devices
bnx2x: bug fix when loading after SAN boot
e1000: Silence sparse warnings by correcting type
igb, ixgbe: netdev_tx_reset_queue incorrectly called from tx init path
openvswitch: Release rtnl_lock if ovs_vport_cmd_build_info() failed.
...
If the requested scsi_dh module is already loaded then skip
request_module().
Multipath table loads can hang in an unnecessary __request_module.
Reported-by: Ben Marzinski <bmarzins@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Fix two places in commit 104655fd4d ("dm thin: support discards") that
didn't use pool->lock to protect against concurrent changes to the
prepared_discards list.
Without this fix, thin_endio() can race with process_discard(), leading
to concurrent list_add()s that result in the processes locking up with
an error like the following:
WARNING: at lib/list_debug.c:32 __list_add+0x8f/0xa0()
...
list_add corruption. next->prev should be prev (ffff880323b96140), but was ffff8801d2c48440. (next=ffff8801d2c485c0).
...
Pid: 17205, comm: kworker/u:1 Tainted: G W O 3.4.0-rc3.snitm+ #1
Call Trace:
[<ffffffff8103ca1f>] warn_slowpath_common+0x7f/0xc0
[<ffffffff8103cb16>] warn_slowpath_fmt+0x46/0x50
[<ffffffffa04f6ce6>] ? bio_detain+0xc6/0x210 [dm_thin_pool]
[<ffffffff8124ff3f>] __list_add+0x8f/0xa0
[<ffffffffa04f70d2>] process_discard+0x2a2/0x2d0 [dm_thin_pool]
[<ffffffffa04f6a78>] ? remap_and_issue+0x38/0x50 [dm_thin_pool]
[<ffffffffa04f7c3b>] process_deferred_bios+0x7b/0x230 [dm_thin_pool]
[<ffffffffa04f7df0>] ? process_deferred_bios+0x230/0x230 [dm_thin_pool]
[<ffffffffa04f7e42>] do_worker+0x52/0x60 [dm_thin_pool]
[<ffffffff81056fa9>] process_one_work+0x129/0x450
[<ffffffff81059b9c>] worker_thread+0x17c/0x3c0
[<ffffffff81059a20>] ? manage_workers+0x120/0x120
[<ffffffff8105eabe>] kthread+0x9e/0xb0
[<ffffffff814ceda4>] kernel_thread_helper+0x4/0x10
[<ffffffff8105ea20>] ? kthread_freezable_should_stop+0x70/0x70
[<ffffffff814ceda0>] ? gs_change+0x13/0x13
---[ end trace 7e0a523bc5e52692 ]---
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Fix a significant memory leak inadvertently introduced during
simplification of cell_release_singleton() in commit
6f94a4c45a ("dm thin: fix stacked bi_next
usage").
A cell's hlist_del() must be accompanied by a mempool_free().
Use __cell_release() to do this, like before.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
In 2009 Philip Reiser notied that a few users of netlink connector
interface needed a capability check and added the idiom
cap_raised(nsp->eff_cap, CAP_SYS_ADMIN) to a few of them, on the premise
that netlink was asynchronous.
In 2011 Patrick McHardy noticed we were being silly because netlink is
synchronous and removed eff_cap from the netlink_skb_params and changed
the idiom to cap_raised(current_cap(), CAP_SYS_ADMIN).
Looking at those spots with a fresh eye we should be calling
capable(CAP_SYS_ADMIN). The only reason I can see for not calling capable
is that it once appeared we were not in the same task as the caller which
would have made calling capable() impossible.
In the initial user_namespace the only difference between between
cap_raised(current_cap(), CAP_SYS_ADMIN) and capable(CAP_SYS_ADMIN) are a
few sanity checks and the fact that capable(CAP_SYS_ADMIN) sets
PF_SUPERPRIV if we use the capability.
Since we are going to be using root privilege setting PF_SUPERPRIV seems
the right thing to do.
The motivation for this that patch is that in a child user namespace
cap_raised(current_cap(),...) tests your capabilities with respect to that
child user namespace not capabilities in the initial user namespace and
thus will allow processes that should be unprivielged to use the kernel
services that are only protected with cap_raised(current_cap(),..).
To fix possible user_namespace issues and to just clean up the code
replace cap_raised(current_cap(), CAP_SYS_ADMIN) with
capable(CAP_SYS_ADMIN).
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Acked-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Acked-by: Andrew G. Morgan <morgan@kernel.org>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Cc: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit 61a0d80c "md/bitmap: discard CHUNK_BLOCK_SHIFT macro"
replaced CHUNK_BLOCK_RATIO() by the same text that was
replacing CHUNK_BLOCK_SHIFT() - which is clearly wrong.
The result is that 'chunks' is often too small by 1,
which can sometimes result in a crash (not sure how).
So use the correct replacement, and get rid of CHUNK_BLOCK_RATIO
which is no longe used.
Reported-by: Karl Newman <siliconfiend@gmail.com>
Tested-by: Karl Newman <siliconfiend@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
commit c744a65c1e
md: don't set md arrays to readonly on shutdown.
removed the possibility of a 'BUG' when data is written to an array
that has just been switched to read-only, but also introduced the
possibility that the array metadata could be corrupted.
If, when md_notify_reboot gets the mddev lock, the array is
in a state where it is assembled but hasn't been started (as can
happen if the personality module is not available, or in other unusual
situations), then incorrect metadata will be written out making it
impossible to re-assemble the array.
So only call __md_stop_writes() if the array has actually been
activated.
This patch is needed for any stable kernel which has had the above
commit applied.
Cc: stable@vger.kernel.org
Reported-by: Christoph Nelles <evilazrael@evilazrael.de>
Signed-off-by: NeilBrown <neilb@suse.de>
Commit 7bfec5f35c
md/raid5: If there is a spare and a want_replacement device, start replacement.
cause md_check_recovery to call ->add_disk much more often.
Instead of only when the array is degraded, it is now called whenever
md_check_recovery finds anything useful to do, which includes
updating the metadata for clean<->dirty transition.
This causes unnecessary work, and causes info messages from ->add_disk
to be reported much too often.
So refine md_check_recovery to only do any actual recovery checking
(including ->add_disk) if MD_RECOVERY_NEEDED is set.
This fix is suitable for 3.3.y:
Cc: stable@vger.kernel.org
Reported-by: Jan Ceuleers <jan.ceuleers@computer.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Fix segfault caused by using rdev_for_each instead of rdev_for_each_safe
Commit dafb20fa34 mistakenly replaced a safe
iterator with an unsafe one when making some macro changes.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
If a bitmap is added while the array is active, it is possible
for bitmap_daemon_work to run while the bitmap is being
initialised.
This is particularly a problem if bitmap_daemon_work sees
bitmap->filemap as non-NULL before it has been filled in properly.
So hold bitmap_info.mutex while filling in ->filemap
to prevent problems.
This patch is suitable for any -stable kernel, though it might not
apply cleanly before about 3.1.
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
If r1bio->sectors % 8 != 0,then the memcmp and a later
memcpy will omit the last bio_vec.
This is suitable for any stable kernel since 3.1 when bad-block
management was introduced.
Cc: stable@vger.kernel.org
Signed-off-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
bitmap_new_disk_sb() would still create V3 bitmap superblock
with host-endian layout.
Perhaps I'm confused, but shouldn't bitmap_new_disk_sb() be
creating a V4 bitmap superblock instead, that is portable,
as per comment in bitmap.h?
Signed-off-by: Andrei Warkentin <andrey.warkentin@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
When comparing two pages read from different legs of a mirror, only
compare the bytes that were read, not the whole page.
In most cases we read a whole page, but in some cases with
bad blocks or odd sizes devices we might read fewer than that.
This bug has been present "forever" but at worst it might cause
a report of two many mismatches and generate a little bit
extra resync IO, so there is no need to back-port to -stable
kernels.
Reported-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
When create a raid5 using assume-clean and echo check or repair to
sync_action.Then component disks did not operated IO but the raid
check/resync faster than normal.
Because the judgement in function analyse_stripe():
if (do_recovery ||
sh->sector >= conf->mddev->recovery_cp)
s->syncing = 1;
else
s->replacing = 1;
When check or repair,the recovery_cp == MaxSectore,so syncing equal zero
not one.
This bug was introduced by commit 9a3e1101b8
md/raid5: detect and handle replacements during recovery.
so this patch is suitable for 3.3-stable.
Cc: stable@vger.kernel.org
Signed-off-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Because rde->nr_pending > 0,so can not remove this disk.
And in any case, we aren't holding rcu_read_lock()
Signed-off-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
raid1 arrays do not have the notion of chunk size. Calculate the
largest chunk sector size we can use to avoid a divide by zero OOPS
when aligning the size of the new array to the chunk size.
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
1/ We can only treat a known-bad-block like a read-error if we
have the data that belongs in that block. So fix that test.
2/ If we cannot recovery a stripe due to insufficient data,
don't tell "md_done_sync" that the sync failed unless we really
did fail something. If we successfully record bad blocks,
that is success.
Reported-by: "majianpeng" <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
This device-mapper target creates a read-only device that transparently
validates the data on one underlying device against a pre-generated tree
of cryptographic checksums stored on a second device.
Two checksum device formats are supported: version 0 which is already
shipping in Chromium OS and version 1 which incorporates some
improvements.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Signed-off-by: Will Drewry <wad@chromium.org>
Signed-off-by: Elly Jones <ellyjones@chromium.org>
Cc: Milan Broz <mbroz@redhat.com>
Cc: Olof Johansson <olofj@chromium.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch introduces a new function dm_bufio_prefetch. It prefetches
the specified range of blocks into dm-bufio cache without waiting
for i/o completion.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Add dm thin target arguments to control discard support.
ignore_discard: Disables discard support
no_discard_passdown: Don't pass discards down to the underlying data
device, but just remove the mapping within the thin provisioning target.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Support discards in the thin target.
On discard the corresponding mapping(s) are removed from the thin
device. If the associated block(s) are no longer shared the discard
is passed to the underlying device.
All bios other than discards now have an associated deferred_entry
that is saved to the 'all_io_entry' in endio_hook. When non-discard
IO completes and associated mappings are quiesced any discards that
were deferred, via ds_add_work() in process_discard(), will be queued
for processing by the worker thread.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
drivers/md/dm-thin.c | 173 ++++++++++++++++++++++++++++++++++++++++++++++----
drivers/md/dm-thin.c | 172 ++++++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 158 insertions(+), 14 deletions(-)
This patch contains the ground work needed for dm-thin to support discard.
- Adds endio function that replaces shared_read_endio.
- Introduce an explicit 'quiesced' flag into the new_mapping structure.
Before, this was implicitly indicated by m->list being empty.
- The map_info->ptr remains constant for the duration of a bio's trip
through the thin target. Make it easier to reason about it.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Support the use of an external _read only_ device as an origin for a thin
device.
Any read to an unprovisioned area of the thin device will be passed
through to the origin. Writes trigger allocation of new blocks as
usual.
One possible use case for this would be VM hosts that want to run
guests on thinly-provisioned volumes but have the base image on another
device (possibly shared between many VMs).
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The thin metadata format can only make use of a device that is <=
THIN_METADATA_MAX_SECTORS (currently 15.9375 GB). Therefore, there is no
practical benefit to using a larger device.
However, it may be that other factors impose a certain granularity for
the space that is allocated to a device (E.g. lvm2 can impose a coarse
granularity through the use of large, >= 1 GB, physical extents).
Rather than reject a larger metadata device, during thin-pool device
construction, switch to allowing it but issue a warning if a device
larger than THIN_METADATA_MAX_SECTORS_WARNING (16 GB) is
provided. Any space over 15.9375 GB will not be used.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Save space by removing entries from the space map ref_count tree if
they're no longer needed.
Ref counts are stored in two places: a bitmap if the ref_count is
below 3, or a btree of uint32_t if 3 or above.
When a ref_count that was above 3 drops below we can remove it from
the tree and save some metadata space. This removal was commented out
before because I was unsure why this was causing under-populated btree
nodes. Earlier patches have fixed this issue.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Commit unwritten data every second to prevent too much building up.
Released blocks don't become available until after the next commit
(for crash resilience). Prior to this patch commits were only
triggered by a message to the target or a REQ_{FLUSH,FUA} bio. This
allowed far too big a position to build up.
The interval is hard-coded to 1 second. This is a sensible setting.
I'm not making this user configurable, since there isn't much to be
gained by tweaking this - and a lot lost by setting it far too high.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Device mapper uses sscanf to convert arguments to numbers. The problem is that
the way we use it ignores additional unmatched characters in the scanned string.
For example, this `if (sscanf(string, "%d", &number) == 1)' will match a number,
but also it will match number with some garbage appended, like "123abc".
As a result, device mapper accepts garbage after some numbers. For example
the command `dmsetup create vg1-new --table "0 16384 linear 254:1bla 34816bla"'
will pass without an error.
This patch fixes all sscanf uses in device mapper. It appends "%c" with
a pointer to a dummy character variable to every sscanf statement.
The construct `if (sscanf(string, "%d%c", &number, &dummy) == 1)' succeeds
only if string is a null-terminated number (optionally preceded by some
whitespace characters). If there is some character appended after the number,
sscanf matches "%c", writes the character to the dummy variable and returns 2.
We check the return value for 1 and consequently reject numbers with some
garbage appended.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The dm-raid code currently fails to create a RAID array if any of the
superblocks cannot be read. This was an oversight as there is already
code to handle this case if the values ('- -') were provided for the
failed array position.
With this patch, if a superblock cannot be read, the array position's
fields are initialized as though '- -' was set in the table. That is,
the device is failed and the position should not be used, but if there
is sufficient redundancy, the array should still be activated.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Fix a harmless typo.
The root is a chunk of data that gets written to the superblock. This
data is used to recreate the space map when opening a metadata area.
We have two space maps; one tracking space on the metadata device and
one of the data device. Both of these use the same format for their
root, so this typo was harmless.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Now that the value_size is held within every node of the btrees we can
remove this argument from value_ptr().
For the last few months a BUG_ON has been checking this argument is
the same as that held in the node. No issues were reported. So this
is a safe change.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The map_context pointer should always be set. However, we have reports
that upon requeuing it is not set correctly. So add set and clear
functions with a BUG_ON() to track the issue properly.
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Acked-by: Hannes Reinecke <hare@suse.de>
Tested-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
As a precaution, set bi_end_io to NULL when failing to remap.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
free_devices in dm_table.c already uses list_for_each(), so we don't
need to check if the list is empty.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove documentation for unimplemented 'trim' message.
I'd planned a 'trim' target message for shrinking thin devices, but
this is better handled via the discard ioctl.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The dm raid module (using md) is becoming the preferred way of creating long-lived
mirrors through userspace LVM so remove the EXPERIMENTAL tag.
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Drop EXPERIMENTAL tag from dm-uevent.
It's not changed for a while and some userspace tools are relying upon it.
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
When we remove an entry from a node we sometimes rebalance with it's
two neighbours. This wasn't being done correctly; in some cases
entries have to move all the way from the right neighbour to the left
neighbour, or vice versa. This patch pretty much re-writes the
balancing code to fix it.
This code is barely used currently; only when you delete a thin
device, and then only if you have hundreds of them in the same pool.
Once we have discard support, which removes mappings, this will be used
much more heavily.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Avoid using the bi_next field for the holder of a cell when deferring
bios because a stacked device below might change it. Store the
holder in a new field in struct cell instead.
When a cell is created, the bio that triggered creation (the holder) was
added to the same bio list as subsequent bios. In some cases we pass
this holder bio directly to devices underneath. If those devices use
the bi_next field there will be trouble...
This also simplifies some code that had to work out which bio was the
holder.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Always set io->error to -EIO when an error is detected in dm-crypt.
There were cases where an error code would be set only if we finish
processing the last sector. If there were other encryption operations in
flight, the error would be ignored and bio would be returned with
success as if no error happened.
This bug is present in kcryptd_crypt_write_convert, kcryptd_crypt_read_convert
and kcryptd_async_done.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@kernel.org
Reviewed-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch fixes a possible deadlock in dm-crypt's mempool use.
Currently, dm-crypt reserves a mempool of MIN_BIO_PAGES reserved pages.
It allocates first MIN_BIO_PAGES with non-failing allocation (the allocation
cannot fail and waits until the mempool is refilled). Further pages are
allocated with different gfp flags that allow failing.
Because allocations may be done in parallel, this code can deadlock. Example:
There are two processes, each tries to allocate MIN_BIO_PAGES and the processes
run simultaneously.
It may end up in a situation where each process allocates (MIN_BIO_PAGES / 2)
pages. The mempool is exhausted. Each process waits for more pages to be freed
to the mempool, which never happens.
To avoid this deadlock scenario, this patch changes the code so that only
the first page is allocated with non-failing gfp mask. Allocation of further
pages may fail.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Call the correct exit function on failure in dm_exception_store_init.
Signed-off-by: Andrei Warkentin <andrey.warkentin@gmail.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Mostly tidying up code in preparation for some bigger changes
next time.
A few bug fixes tagged for -stable.
Main functionality change is that some RAID10 arrays can now
grow to use extra space that may have been made available on the
individual devices.
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Merge tag 'md-3.4' of git://neil.brown.name/md
Pull md updates for 3.4 from Neil Brown:
"Mostly tidying up code in preparation for some bigger changes next
time.
A few bug fixes tagged for -stable.
Main functionality change is that some RAID10 arrays can now grow to
use extra space that may have been made available on the individual
devices."
Fixed up trivial conflicts with the k[un]map_atomic() cleanups in
drivers/md/bitmap.c.
* tag 'md-3.4' of git://neil.brown.name/md: (22 commits)
md: Add judgement bb->unacked_exist in function md_ack_all_badblocks().
md: fix clearing of the 'changed' flags for the bad blocks list.
md/bitmap: discard CHUNK_BLOCK_SHIFT macro
md/bitmap: remove unnecessary indirection when allocating.
md/bitmap: remove some pointless locking.
md/bitmap: change a 'goto' to a normal 'if' construct.
md/bitmap: move printing of bitmap status to bitmap.c
md/bitmap: remove some unused noise from bitmap.h
md/raid10 - support resizing some RAID10 arrays.
md/raid1: handle merge_bvec_fn in member devices.
md/raid10: handle merge_bvec_fn in member devices.
md: add proper merge_bvec handling to RAID0 and Linear.
md: tidy up rdev_for_each usage.
md/raid1,raid10: avoid deadlock during resync/recovery.
md/bitmap: ensure to load bitmap when creating via sysfs.
md: don't set md arrays to readonly on shutdown.
md: allow re-add to failed arrays.
md/raid5: use atomic_dec_return() instead of atomic_dec() and atomic_read().
md: Use existed macros instead of numbers
md/raid5: removed unused 'added_devices' variable.
...
Pull kmap_atomic cleanup from Cong Wang.
It's been in -next for a long time, and it gets rid of the (no longer
used) second argument to k[un]map_atomic().
Fix up a few trivial conflicts in various drivers, and do an "evil
merge" to catch some new uses that have come in since Cong's tree.
* 'kmap_atomic' of git://github.com/congwang/linux: (59 commits)
feature-removal-schedule.txt: schedule the deprecated form of kmap_atomic() for removal
highmem: kill all __kmap_atomic() [swarren@nvidia.com: highmem: Fix ARM build break due to __kmap_atomic rename]
drbd: remove the second argument of k[un]map_atomic()
zcache: remove the second argument of k[un]map_atomic()
gma500: remove the second argument of k[un]map_atomic()
dm: remove the second argument of k[un]map_atomic()
tomoyo: remove the second argument of k[un]map_atomic()
sunrpc: remove the second argument of k[un]map_atomic()
rds: remove the second argument of k[un]map_atomic()
net: remove the second argument of k[un]map_atomic()
mm: remove the second argument of k[un]map_atomic()
lib: remove the second argument of k[un]map_atomic()
power: remove the second argument of k[un]map_atomic()
kdb: remove the second argument of k[un]map_atomic()
udf: remove the second argument of k[un]map_atomic()
ubifs: remove the second argument of k[un]map_atomic()
squashfs: remove the second argument of k[un]map_atomic()
reiserfs: remove the second argument of k[un]map_atomic()
ocfs2: remove the second argument of k[un]map_atomic()
ntfs: remove the second argument of k[un]map_atomic()
...
Pull trivial tree from Jiri Kosina:
"It's indeed trivial -- mostly documentation updates and a bunch of
typo fixes from Masanari.
There are also several linux/version.h include removals from Jesper."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (101 commits)
kcore: fix spelling in read_kcore() comment
constify struct pci_dev * in obvious cases
Revert "char: Fix typo in viotape.c"
init: fix wording error in mm_init comment
usb: gadget: Kconfig: fix typo for 'different'
Revert "power, max8998: Include linux/module.h just once in drivers/power/max8998_charger.c"
writeback: fix fn name in writeback_inodes_sb_nr_if_idle() comment header
writeback: fix typo in the writeback_control comment
Documentation: Fix multiple typo in Documentation
tpm_tis: fix tis_lock with respect to RCU
Revert "media: Fix typo in mixer_drv.c and hdmi_drv.c"
Doc: Update numastat.txt
qla4xxx: Add missing spaces to error messages
compiler.h: Fix typo
security: struct security_operations kerneldoc fix
Documentation: broken URL in libata.tmpl
Documentation: broken URL in filesystems.tmpl
mtd: simplify return logic in do_map_probe()
mm: fix comment typo of truncate_inode_pages_range
power: bq27x00: Fix typos in comment
...
If there are no unacked bad blocks, then there is no point searching
for them to acknowledge them.
Signed-off-by: majianpeng <majianpeng@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
In super_1_sync (the first hunk) we need to clear 'changed' before
checking read_seqretry(), otherwise we might race with other code
adding a bad block and so won't retry later.
In md_update_sb (the second hunk), in the case where there is no
metadata (neither persistent nor external), we treat any bad blocks as
an error. However we need to clear the 'changed' flag before calling
md_ack_all_badblocks, else it won't do anything.
This patch is suitable for -stable release 3.0 and later.
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
Be redefining ->chunkshift as the shift from sectors to chunks rather
than bytes to chunks, we can just use "bitmap->chunkshift" which is
shorter than the macro call, and less indirect.
Signed-off-by: NeilBrown <neilb@suse.de>
These funcitons don't add anything useful except possibly the trace
points, and I don't think they are worth the extra indirection.
So remove them.
Signed-off-by: NeilBrown <neilb@suse.de>
There is nothing gained by holding a lock while we check if a pointer
is NULL or not. If there could be a race, then it could become NULL
immediately after the unlock - but there is no race here.
So just remove the locking.
Signed-off-by: NeilBrown <neilb@suse.de>
The use of a goto makes the control flow more obscure here.
So make it a normal:
if (x) {
Y;
}
No functional change.
Signed-off-by: NeilBrown <neilb@suse.de>
The part of /proc/mdstat which describes the bitmap should really
be generated by code in bitmap.c. So move it there.
Signed-off-by: NeilBrown <neilb@suse.de>
'resizing' an array in this context means making use of extra
space that has become available in component devices, not adding new
devices.
It also includes shrinking the array to take up less space of
component devices.
This is not supported for array with a 'far' layout. However
for 'near' and 'offset' layout arrays, adding and removing space at
the end of the devices is easy to support, and this patch provides
that support.
Signed-off-by: NeilBrown <neilb@suse.de>
Currently we don't honour merge_bvec_fn in member devices so if there
is one, we force all requests to be single-page at most.
This is not ideal.
So create a raid1 merge_bvec_fn to check that function in children
as well.
This introduces a small problem. There is no locking around calls
the ->merge_bvec_fn and subsequent calls to ->make_request. So a
device added between these could end up getting a request which
violates its merge_bvec_fn.
Currently the best we can do is synchronize_sched(). This will work
providing no preemption happens. If there is is preemption, we just
have to hope that new devices are largely consistent with old devices.
Signed-off-by: NeilBrown <neilb@suse.de>
Currently we don't honour merge_bvec_fn in member devices so if there
is one, we force all requests to be single-page at most.
This is not ideal.
So enhance the raid10 merge_bvec_fn to check that function in children
as well.
This introduces a small problem. There is no locking around calls
the ->merge_bvec_fn and subsequent calls to ->make_request. So a
device added between these could end up getting a request which
violates its merge_bvec_fn.
Currently the best we can do is synchronize_sched(). This will work
providing no preemption happens. If there is preemption, we just
have to hope that new devices are largely consistent with old devices.
Signed-off-by: NeilBrown <neilb@suse.de>
These personalities currently set a max request size of one page
when any member device has a merge_bvec_fn because they don't
bother to call that function.
This causes extra works in splitting and combining requests.
So make the extra effort to call the merge_bvec_fn when it exists
so that we end up with larger requests out the bottom.
Signed-off-by: NeilBrown <neilb@suse.de>
md.h has an 'rdev_for_each()' macro for iterating the rdevs in an
mddev. However it uses the 'safe' version of list_for_each_entry,
and so requires the extra variable, but doesn't include 'safe' in the
name, which is useful documentation.
Consequently some places use this safe version without needing it, and
many use an explicity list_for_each entry.
So:
- rename rdev_for_each to rdev_for_each_safe
- create a new rdev_for_each which uses the plain
list_for_each_entry,
- use the 'safe' version only where needed, and convert all other
list_for_each_entry calls to use rdev_for_each.
Signed-off-by: NeilBrown <neilb@suse.de>
If RAID1 or RAID10 is used under LVM or some other stacking
block device, it is possible to enter a deadlock during
resync or recovery.
This can happen if the upper level block device creates
two requests to the RAID1 or RAID10. The first request gets
processed, blocks recovery and queue requests for underlying
requests in current->bio_list. A resync request then starts
which will wait for those requests and block new IO.
But then the second request to the RAID1/10 will be attempted
and it cannot progress until the resync request completes,
which cannot progress until the underlying device requests complete,
which are on a queue behind that second request.
So allow that second request to proceed even though there is
a resync request about to start.
This is suitable for any -stable kernel.
Cc: stable@vger.kernel.org
Reported-by: Ray Morris <support@bettercgi.com>
Tested-by: Ray Morris <support@bettercgi.com>
Signed-off-by: NeilBrown <neilb@suse.de>
When commit 69e51b449d (md/bitmap: separate out loading a bitmap...)
created bitmap_load, it missed calling it after bitmap_create when a
bitmap is created through the sysfs interface.
So if a bitmap is added this way, we don't allocate memory properly
and can crash.
This is suitable for any -stable release since 2.6.35.
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
It seems that with recent kernel, writeback can still be happening
while shutdown is happening, and consequently data can be written
after the md reboot notifier switches all arrays to read-only.
This causes a BUG.
So don't switch them to read-only - just mark them clean and
set 'safemode' to '2' which mean that immediately after any
write the array will be switch back to 'clean'.
This could result in the shutdown happening when array is marked
dirty, thus forcing a resync on reboot. However if you reboot
without performing a "sync" first, you get to keep both halves.
This is suitable for any stable kernel (though there might be some
conflicts with obvious fixes in earlier kernels).
Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
When an array is failed (some data inaccessible) then there is no
point attempting to add a spare as it could not possibly be recovered.
However that may be value in re-adding a recently removed device.
e.g. if there is a write-intent-bitmap and it is clear, then access
to the data could be restored by this action.
So don't reject a re-add to a failed array for RAID10 and RAID5 (the
only arrays types that check for a failed array).
Signed-off-by: NeilBrown <neilb@suse.de>
Recent commit 4ca40c2ce0 (md/raid10: Allow replacement device ...)
added an smp_mb in end_sync_write.
This was to close a possible race with raid10_remove_disk.
However there is no such race as it is never attempted to remove a
disk while resync (or recovery) is happening.
so the smp_mb is just noise.
Signed-off-by: NeilBrown <neilb@suse.de>
Fix dm-raid flush support.
Both md and dm have support for flush, but the dm-raid target
forgot to set the flag to indicate that flushes should be
passed on. (Important for data integrity e.g. with writeback cache
enabled.)
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The 'rebuild' parameter is used to rebuild individual devices in an
array (e.g. resynchronize a RAID1 device or recalculate a parity device
in higher RAID). The MD_CHANGE_DEVS flag must be set when this
parameter is given in order to write out the superblocks and make the
change take immediate effect. The code that handles new devices in
super_load already sets MD_CHANGE_DEVS and 'FirstUse'. (The 'FirstUse'
flag was being set as a special case for rebuilds in
super_init_validation.)
Add a condition for rebuilds in super_load to take care of both flags
without the special case in 'super_init_validation'.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Correct the number of mapped sectors shown on a thin device's
status line by decrementing td->mapped_blocks in __remove() each time
a block is removed.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
If dm_sm_disk_create() fails the superblock must be unlocked.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The __open_device() error paths in __create_thin() and __create_snap()
incorrectly call __close_device() even if td was not initialized by
__open_device(). Remove this.
Also document __open_device() return values, remove a redundant
td->changed = 1 in __create_thin(), and insert an additional
safeguard against creating an already-existing device.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The following BUG is hit on the first read that is submitted to a dm
flakey test device while the device is "down" if the corrupt_bio_byte
feature wasn't requested when the device's table was loaded.
Example DM table that will hit this BUG:
0 2097152 flakey 8:0 2048 0 30
This bug was introduced by commit a3998799fb
(dm flakey: add corrupt_bio_byte feature) in v3.1-rc1.
BUG: unable to handle kernel paging request at ffff8801cfce3fff
IP: [<ffffffffa008c233>] corrupt_bio_data+0x6e/0xae [dm_flakey]
PGD 1606063 PUD 0
Oops: 0002 [#1] SMP
...
Call Trace:
<IRQ>
[<ffffffffa008c2b5>] flakey_end_io+0x42/0x48 [dm_flakey]
[<ffffffffa00dca98>] clone_endio+0x54/0xb6 [dm_mod]
[<ffffffff81130587>] bio_endio+0x2d/0x2f
[<ffffffff811c819a>] req_bio_endio+0x96/0x9f
[<ffffffff811c94b9>] blk_update_request+0x1dc/0x3a9
[<ffffffff812f5ee2>] ? rcu_read_unlock+0x21/0x23
[<ffffffff811c96a6>] blk_update_bidi_request+0x20/0x6e
[<ffffffff811c9713>] blk_end_bidi_request+0x1f/0x5d
[<ffffffff811c978d>] blk_end_request+0x10/0x12
[<ffffffff8128f450>] scsi_io_completion+0x1e5/0x4b1
[<ffffffff812882a9>] scsi_finish_command+0xec/0xf5
[<ffffffff8128f830>] scsi_softirq_done+0xff/0x108
[<ffffffff811ce284>] blk_done_softirq+0x84/0x98
[<ffffffff81048d19>] __do_softirq+0xe3/0x1d5
[<ffffffff8138f83f>] ? _raw_spin_lock+0x62/0x69
[<ffffffff810997cf>] ? handle_irq_event+0x4c/0x61
[<ffffffff8139833c>] call_softirq+0x1c/0x30
[<ffffffff81003b37>] do_softirq+0x4b/0xa3
[<ffffffff81048a39>] irq_exit+0x53/0xca
[<ffffffff81398acd>] do_IRQ+0x9d/0xb4
[<ffffffff81390333>] common_interrupt+0x73/0x73
...
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org # 3.1+
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch fixes a crash by recognising discards in dm_io.
Currently dm_mirror can send REQ_DISCARD bios if running over a
discard-enabled device and without support in dm_io the system
crashes badly.
BUG: unable to handle kernel paging request at 00800000
IP: __bio_add_page.part.17+0xf5/0x1e0
...
bio_add_page+0x56/0x70
dispatch_io+0x1cf/0x240 [dm_mod]
? km_get_page+0x50/0x50 [dm_mod]
? vm_next_page+0x20/0x20 [dm_mod]
? mirror_flush+0x130/0x130 [dm_mirror]
dm_io+0xdc/0x2b0 [dm_mod]
...
Introduced in 2.6.38-rc1 by commit 5fc2ffeabb
(dm raid1: support discard).
Signed-off-by: Milan Broz <mbroz@redhat.com>
Cc: stable@kernel.org
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
If 'argc' is zero we jump to the 'out:' label, but this leaks the
(unused) memory that 'dm_split_args()' allocated for 'argv' if the
string being split consisted entirely of whitespace. Jump to the
'out_argv:' label instead to free up that memory.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2 relate to the recently added drive replacement.
One causes read error in RAID10 to sometimes be retried indefinitely.
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Merge tag 'md-3.3-fixes' of git://neil.brown.name/md
Pull md fixes from Neil Brown:
"Three fixes for md in 3.3-rc: Two relate to the recently added drive
replacement. One fixes the problem where a read error in RAID10 would
sometimes be retried indefinitely."
* tag 'md-3.3-fixes' of git://neil.brown.name/md:
md/raid10: fix assembling of arrays with replacement devices.
md/raid10: fix handling of error on last working device in array.
md/raid1: fix buglet in md_raid1_contested.
commit 56a2559bb6 (md/raid10: recognise replacements ...)
changed 'run' to set ->replacement or ->rdev depending on the
'Replacement' status if the device, but it didn't remove the
old unconditional setting of 'rdev'. So it was largely ineffective.
So remove that now.
Signed-off-by: NeilBrown <neilb@suse.de>
If we get a read error on the last working device in a RAID10 which
contains the target block, then we don't fail the device (which is
good) but we don't abort retries, which is wrong.
We end up in an infinite loop retrying the read on the one device.
This patch fixes the problem in two places:
1/ in raid10_end_read_request we don't even ask for a retry if this
was the last usable device. This is efficient but a little racy
and will sometimes retry when it should not.
2/ in handle_read_error we are careful to exclude any device from
retry which we tried to mark as faulty (that might have failed if
it was the last device). This is race-free but less efficient.
Signed-off-by: NeilBrown <neilb@suse.de>
Since we added 'replacement' capability, RAID1 can have twice
as many devices as ->raid_disks indicates.
So md_raid1_congested needs to check that many possible devices,
not just ->raid_disks many.
Signed-off-by: NeilBrown <neilb@suse.de>
1/ two small fixes to ensure we handle an interrupted resync properly.
2/ avoid loading the bitmap multiple times in dm-raid
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Merge tag 'md-3.3-fixes' of git://neil.brown.name/md
Some simple md-related fixes.
1/ two small fixes to ensure we handle an interrupted resync properly.
2/ avoid loading the bitmap multiple times in dm-raid
* tag 'md-3.3-fixes' of git://neil.brown.name/md:
md: two small fixes to handling interrupt resync.
Prevent DM RAID from loading bitmap twice.
1/ If a resync is aborted we should record how far we got
(recovery_cp) the last request that we know has completed
(->curr_resync_completed) rather than the last request that was
submitted (->curr_resync).
2/ When a resync aborts we still want to update the metadata with
any changes, so set MD_CHANGE_DEVS even if we 'skip'.
Signed-off-by: NeilBrown <neilb@suse.de>
As 'make versioncheck' points out, drivers/md/dm-bufio.c has no need to include
linux/version.h, so this patch removes the unneeded include.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Acked-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The life cycle of a device-mapper target is:
1) create
2) resume
3) suspend
*) possibly repeat from 2
4) destroy
The dm-raid target is unconditionally calling MD's bitmap_load function upon
every resume. If steps 2 & 3 above are repeated, bitmap_load is called
multiple times. It is only written to be called once; otherwise, it allocates
new memory for the bitmap (without freeing the old) and incrementing the number
of pages it thinks it has without zeroing first. This ultimately leads to
access beyond allocated memory and lost memory.
Simply avoiding the bitmap_load call upon resume is not sufficient. If the
target was suspended while the initial recovery was only partially complete,
it needs to be restarted when the target is resumed. This is why
'md_wakeup_thread' is called before issuing the 'mddev_resume'.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
* 'for-3.3/core' of git://git.kernel.dk/linux-block: (37 commits)
Revert "block: recursive merge requests"
block: Stop using macro stubs for the bio data integrity calls
blockdev: convert some macros to static inlines
fs: remove unneeded plug in mpage_readpages()
block: Add BLKROTATIONAL ioctl
block: Introduce blk_set_stacking_limits function
block: remove WARN_ON_ONCE() in exit_io_context()
block: an exiting task should be allowed to create io_context
block: ioc_cgroup_changed() needs to be exported
block: recursive merge requests
block, cfq: fix empty queue crash caused by request merge
block, cfq: move icq creation and rq->elv.icq association to block core
block, cfq: restructure io_cq creation path for io_context interface cleanup
block, cfq: move io_cq exit/release to blk-ioc.c
block, cfq: move icq cache management to block core
block, cfq: move io_cq lookup to blk-ioc.c
block, cfq: move cfqd->icq_list to request_queue and add request->elv.icq
block, cfq: reorganize cfq_io_context into generic and cfq specific parts
block: remove elevator_queue->ops
block: reorder elevator switch sequence
...
Fix up conflicts in:
- block/blk-cgroup.c
Switch from can_attach_task to can_attach
- block/cfq-iosched.c
conflict with now removed cic index changes (we now use q->id instead)
A logical volume can map to just part of underlying physical volume.
In this case, it must be treated like a partition.
Based on a patch from Alasdair G Kergon.
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: dm-devel@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
One is a recently introduced regression that affects an unusual
configuration with a guaranteed BUG_ON. Has been tagged for -stable.
The other is minor missing functionality.
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Merge tag 'md-3.3-fixes' of git://neil.brown.name/md
Two bugfixes for md.
One is a recently introduced regression that affects an unusual
configuration with a guaranteed BUG_ON. Has been tagged for -stable.
The other is minor missing functionality.
* tag 'md-3.3-fixes' of git://neil.brown.name/md:
md/raid1: perform bad-block tests for WriteMostly devices too.
md: notify the 'degraded' sysfs attribute on failure.
Stacking driver queue limits are typically bounded exclusively by the
capabilities of the low level devices, not by the stacking driver
itself.
This patch introduces blk_set_stacking_limits() which has more liberal
metrics than the default queue limits function. This allows us to
inherit topology parameters from bottom devices without manually
tweaking the default limits in each driver prior to calling the stacking
function.
Since there is now a clear distinction between stacking and low-level
devices, blk_set_default_limits() has been modified to carry the more
conservative values that we used to manually set in
blk_queue_make_request().
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We normally try to avoid reading from write-mostly devices, but when
we do we really have to check for bad blocks and be sure not to
try reading them.
With the current code, best_good_sectors might not get set and that
causes zero-length read requests to be send down which is very
confusing.
This bug was introduced in commit d2eb35acfd and so the patch
is suitable for 3.1.x and 3.2.x
Reported-and-tested-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reported-and-tested-by: Art -kwaak- van Breemen <ard@telegraafnet.nl>
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: stable@vger.kernel.org
We currently only 'notify' changes to the 'degraded' attribute
when it decreases, not when it increases.
Notifying on failure is a little awkward as it happen in
interrupt context.
So instead, notify when we remove the failed device from the array,
which is very soon afterwards.
Reported-and-tested-by: Mikhail Balabin <mbalabin@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Big change is new hot-replacement.
A slot in an array can hold 2 devices - one that
wants-replacement and one that is the replacement.
Once the replacement is built - either from the
original or (in the case of errors) from elsewhere,
the wants-replacement device will be removed.
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Merge tag 'md-3.3' of git://neil.brown.name/md
md update for 3.3
Big change is new hot-replacement.
A slot in an array can hold 2 devices - one that
wants-replacement and one that is the replacement.
Once the replacement is built - either from the
original or (in the case of errors) from elsewhere,
the wants-replacement device will be removed.
* tag 'md-3.3' of git://neil.brown.name/md: (36 commits)
md/raid1: Mark device want_replacement when we see a write error.
md/raid1: If there is a spare and a want_replacement device, start replacement.
md/raid1: recognise replacements when assembling arrays.
md/raid1: handle activation of replacement device when recovery completes.
md/raid1: Allow a failed replacement device to be removed.
md/raid1: Allocate spare to store replacement devices and their bios.
md/raid1: Replace use of mddev->raid_disks with conf->raid_disks.
md/raid10: If there is a spare and a want_replacement device, start replacement.
md/raid10: recognise replacements when assembling array.
md/raid10: Allow replacement device to be replace old drive.
md/raid10: handle recovery of replacement devices.
md/raid10: Handle replacement devices during resync.
md/raid10: writes should get directed to replacement as well as original.
md/raid10: allow removal of failed replacement devices.
md/raid10: preferentially read from replacement device if possible.
md/raid10: change read_balance to return an rdev
md/raid10: prepare data structures for handling replacement.
md/raid5: Mark device want_replacement when we see a write error.
md/raid5: If there is a spare and a want_replacement device, start replacement.
md/raid5: recognise replacements when assembling array.
...
Move invalidate_bdev, block_sync_page into fs/block_dev.c. Export
kill_bdev as well, so brd doesn't have to open code it. Reduce
buffer_head.h requirement accordingly.
Removed a rather large comment from invalidate_bdev, as it looked a bit
obsolete to bother moving. The small comment replacing it says enough.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Now that WantReplacement drives are replaced cleanly, mark a drive
as want_replacement when we see a write error. It might get failed soon so
the WantReplacement flag is irrelevant, but if the write error is recorded
in the bad block log, we still want to activate any spare that might
be available.
Signed-off-by: NeilBrown <neilb@suse.de>
When attempting to add a spare to a RAID1 array, also consider
adding it as a replacement for a want_replacement device.
Signed-off-by: NeilBrown <neilb@suse.de>
If a Replacement is seen, file it as such.
If we see two replacements (or two normal devices) for the one slot,
abort.
Signed-off-by: NeilBrown <neilb@suse.de>
When recovery completes ->spare_active is called.
This checks if the replacement is ready and if so it fails
the original.
Signed-off-by: NeilBrown <neilb@suse.de>
In RAID1, a replacement is much like a normal device, so we just
double the size of the relevant arrays and look at all possible
devices for reads and writes.
This means that the array looks like it is now double the size in some
way - we need to be careful about that.
In particular, we checking if the array is still degraded while
creating a recovery request we need to only consider the first 'half'
- i.e. the real (non-replacement) devices.
Signed-off-by: NeilBrown <neilb@suse.de>
In general mddev->raid_disks can change unexpectedly while
conf->raid_disks will only change in a very controlled way. So change
some uses of one to the other.
The use of mddev->raid_disks will not cause actually problems but
this way is more consistent and safer in the long term.
Signed-off-by: NeilBrown <neilb@suse.de>
When attempting to add a spare to a RAID10 array, also consider
adding it as a replacement for a want_replacement device.
Signed-off-by: NeilBrown <neilb@suse.de>
If a Replacement is seen, file it as such.
If we see two replacements (or two normal devices) for the one slot,
abort.
Signed-off-by: NeilBrown <neilb@suse.de>
When recovery finish and spare_active is called, check for a
replace that might have just become fully synced and mark it
as such, marking the original as failed.
Then when the original is removed, move the replacement into
its position.
This means that 'replacement' and spontaneously become NULL in some
situations. Make sure we check for those.
It also means that 'rdev' and 'replacement' could appear to be
identical - check for that too.
Signed-off-by: NeilBrown <neilb@suse.de>
If there is a replacement device, then recover to it,
reading from any drives - maybe the one being replaced, maybe not.
Signed-off-by: NeilBrown <neilb@suse.de>
If we need to resync an array which has replacement devices,
we always write any block checked to every replacement.
If the resync was bitmap-based resync we will then complete the
replacement normally.
If it was a full resync, we mark the replacements as fully recovered
when the resync finishes so no further recovery is needed.
Signed-off-by: NeilBrown <neilb@suse.de>
When writing, we need to submit two writes, one to the original,
and one to the replacements - if there is a replacement.
If the write to the replacement results in a write error we just
fail the device. We only try to record write errors to the
original.
This only handles writing new data. Writing for resync/recovery
will come later.
Signed-off-by: NeilBrown <neilb@suse.de>
When reading (for array reads, not for recovery etc) we read from the
replacement device if it has recovered far enough.
This requires storing the chosen rdev in the 'r10_bio' so we can make
sure to drop the ref on the right device when the read finishes.
Signed-off-by: NeilBrown <neilb@suse.de>
It makes more sense to return an rdev than just an index as
read_balance() gets a reference to the rdev and so returning
the pointer make this more idiomatic.
This will be needed in a future patch when we might return
a 'replacement' rdev instead of the main rdev.
Signed-off-by: NeilBrown <neilb@suse.de>
Allow each slot in the RAID10 to have 2 devices, the want_replacement
and the replacement.
Also an r10bio to have 2 bios, and for resync/recovery allocate the
second bio if there are any replacement devices.
Signed-off-by: NeilBrown <neilb@suse.de>
Now that WantReplacement drives are replaced cleanly, mark a drive
as WantReplacement when we see a write error. It might get failed soon so
the WantReplacement flag is irrelevant, but if the write error is recorded
in the bad block log, we still want to activate any spare that might
be available.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
When attempting to add a spare to a RAID[456] array, also consider
adding it as a replacement for a want_replacement device.
This requires that common md code attempt hot_add even when the array
is not formally degraded.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
If a Replacement is seen, file it as such.
If we see two replacements (or two normal devices) for the one slot,
abort.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
When recovery completes - as reported by a call to ->spare_active,
we clear In_sync on the original and set it on the replacement.
Then when the original gets removed we move the replacement from
'replacement' to 'rdev'.
This could race with other code that is looking at these pointers,
so we use memory barriers and careful ordering to ensure that
a reader might see one device twice, but never no devices.
Then the readers guard against using both devices, which could
only happen when writing.
Signed-off-by: NeilBrown <neilb@suse.de>
During recovery we want to write to the replacement but not
the original. So we have two new flags
- R5_NeedReplace if this stripe has a replacement that needs to
be written at some stage
- R5_WantReplace if NeedReplace, and the data is available, and
a 'sync' has been requested on this stripe.
We also distinguish between 'sync and replace' which need to read
all other devices, and 'replace' which only needs to read the
devices being replaced.
Note that during resync we always write to any replacement device.
It might not need to be written to, but as we don't read to compare,
we have to write to be sure.
Signed-off-by: NeilBrown <neilb@suse.de>
When writing, we need to submit two writes, one to the original, and
one to the replacement - if there is a replacement.
If the write to the replacement results in a write error, we just fail
the device. We only try to record write errors to the original.
When writing for recovery, we shouldn't write to the original. This
will be addressed in a subsequent patch that generally addresses
recovery.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Enhance raid5_remove_disk to be able to remove ->replacement
as well as ->rdev.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
If a replacement device is present and has been recovered far enough,
then use it for reading into the stripe cache.
If we get an error we don't try to repair it, we just fail the device.
A replacement device that gives errors does not sound sensible.
This requires removing the setting of R5_ReadError when we get
a read error during a read that bypasses the cache. It was probably
a bad idea anyway as we don't know that every block in the read
caused an error, and it could cause ReadError to be set for the
replacement device, which is bad.
Signed-off-by: NeilBrown <neilb@suse.de>
We current initialise some fields of a bio when preparing a
stripe_head, and again just before submitting the request.
Remove the duplication by only setting the fields that lower level
devices don't touch in raid5_build_block, and only set the changeable
fields in ops_run_io.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Remove some #defines that are no longer used, and replace some
others with an enum.
And remove an unused field.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Just enhance data structures to record a second device per slot to be
used as a 'replacement' device, replacing the original.
We also have a second bio in each slot in each stripe_head. This will
only be used when writing to the array - we need to write to both the
original and the replacement at the same time, so will need two bios.
For now, only try using the replacement drive for aligned-reads.
In this case, we prefer the replacement if it has been recovered far
enough, otherwise use the original.
This includes a small enhancement. Previously we would only do
aligned reads if the target device was fully recovered. Now we also
do them if it has recovered far enough.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
hot-replace is a feature being added to md which will allow a
device to be replaced without removing it from the array first.
With hot-replace a spare can be activated and recovery can start while
the original device is still in place, thus allowing a transition from
an unreliable device to a reliable device without leaving the array
degraded during the transition. It can also be use when the original
device is still reliable but it not wanted for some reason.
This will eventually be supported in RAID4/5/6 and RAID10.
This patch adds a super-block flag to distinguish the replacement
device. If an old kernel sees this flag it will reject the device.
It also adds two per-device flags which are viewable and settable via
sysfs.
"want_replacement" can be set to request that a device be replaced.
"replacement" is set to show that this device is replacing another
device.
The "rd%d" links in /sys/block/mdXx/md only apply to the original
device, not the replacement. We currently don't make links for the
replacement - there doesn't seem to be a need.
Signed-off-by: NeilBrown <neilb@suse.de>
Soon an array will be able to have multiple devices with the
same raid_disk number (an original and a replacement). So removing
a device based on the number won't work. So pass the actual device
handle instead.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
When setting the slot number on a device in an active array we
currently check that the number is not already in use.
We then call into the personality's hot_add_disk function
which performs the same test and returns the same error.
Thus the common test is not needed.
As we will shortly be changing some personalities to allow duplicates
in some cases (to support hot-replace), the common test will become
inconvenient.
So remove the common test.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
For each active region corresponding to a bit in the bitmap with have
a 14bit counter (and some flags).
This counts
number of active writes + bit in the on-disk bitmap + delay-needed.
The "delay-needed" is because we always want a delay before clearing a
bit. So the number here is normally number of active writes plus 2.
If there have been no writes for a while, we drop to 1.
If still no writes we clear the bit and drop to 0.
So for consistency, when setting bit from the on-disk bitmap or by
request from user-space it is best to set the counter to '2' to start
with.
In particular we might also set the NEEDED_MASK flag at this time, and
in all other cases NEEDED_MASK is only set when the counter is 2 or
more.
Signed-off-by: NeilBrown <neilb@suse.de>
When an array is being reshaped to change the number of devices,
the two halves can be differently degraded. e.g. one could be
missing a device and the other not.
So we need to be more careful about calculating the 'degraded'
attribute.
Instead of just inc/dec at appropriate times, perform a full
re-calculation examining both possible cases. This doesn't happen
often so it not a big cost, and we already have most of the code to
do it.
Signed-off-by: NeilBrown <neilb@suse.de>
We have a variable 'mddev' in this function, but repeatedly get the
same value by dereferencing bitmap->mddev.
There is room for simplification here...
Signed-off-by: NeilBrown <neilb@suse.de>
The info is already available in /proc/mdstat and /sys/block in
an accessible form so there is no point in putting a road-block in
the ioctl for information gathering.
Signed-off-by: NeilBrown <neilb@suse.de>
commit d0a4bb4927 introduced a
regression which is annoying but fairly harmless.
When writing to an array that is undergoing recovery (a spare
in being integrated into the array), writing to the array will
set bits in the bitmap, but they will not be cleared when the
write completes.
For bits covering areas that have not been recovered yet this is not a
problem as the recovery will clear the bits. However bits set in
already-recovered region will stay set and never be cleared.
This doesn't risk data integrity. The only negatives are:
- next time there is a crash, more resyncing than necessary will
be done.
- the bitmap doesn't look clean, which is confusing.
While an array is recovering we don't want to update the
'events_cleared' setting in the bitmap but we do still want to clear
bits that have very recently been set - providing they were written to
the recovering device.
So split those two needs - which previously both depended on 'success'
and always clear the bit of the write went to all devices.
Signed-off-by: NeilBrown <neilb@suse.de>
Before performing a recovery we try to remove any spares that
might not be working, then add any that might have become relevant.
Currently we abort on the first spare that cannot be added.
This is a false optimisation.
It is conceivable that - depending on rules in the personality - a
subsequent spare might be accepted.
Also the loop does other things like count the available spares and
reset the 'recovery_offset' value.
If we abort early these might not happen properly.
So remove the early abort.
In particular if you have an array what is undergoing recovery and
which has extra spares, then the recovery may not restart after as
reboot as the could of 'spares' might end up as zero.
Reported-by: Anssi Hannula <anssi.hannula@iki.fi>
Signed-off-by: NeilBrown <neilb@suse.de>
While reshaping a degraded array (as when reshaping a RAID0 by first
converting it to a degraded RAID4) we currently get confused about
which devices are in_sync. In most cases we get it right, but in the
region that is being reshaped we need to treat non-failed devices as
in-sync when we have the data but haven't actually written it out yet.
Reported-by: Adam Kwolek <adam.kwolek@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
commit d70ed2e4fa
broke hot-add to a linear array.
After that commit, metadata if not written to devices until they
have been fully integrated into the array as determined by
saved_raid_disk. That patch arranged to clear that field after
a recovery completed.
However for linear arrays, there is no recovery - the integration is
instantaneous. So we need to explicitly clear the saved_raid_disk
field.
Signed-off-by: NeilBrown <neilb@suse.de>
Once a device is failed we really want to completely ignore it.
It should go away soon anyway.
In particular the presence of bad blocks on it should not cause us to
block as we won't be trying to write there anyway.
So as soon as we can check if a device is Faulty, do so and pretend
that it is already gone if it is Faulty.
Signed-off-by: NeilBrown <neilb@suse.de>
When we mark blocks as bad we need them to be acknowledged by the
metadata handler promptly.
For an in-kernel metadata handler that was already being done. But
for an external metadata handler we need to alert it of the change by
sending a notification through the sysfs file. This adds that
notification.
Signed-off-by: NeilBrown <neilb@suse.de>
Once a device is marked Faulty the badblocks - whether acknowledged or
not - become irrelevant. So they shouldn't cause the device to be
marked as Blocked.
Without this patch, a process might write "-blocked" to clear the
Blocked status, but while that will correctly fail the device, it
won't remove the apparent 'blocked' status.
Signed-off-by: NeilBrown <neilb@suse.de>
When we are accessing an mddev via sysfs we know that the
mddev cannot disappear because it has an embedded kobj which
is refcounted by sysfs.
And we also take the mddev_lock.
However this is not enough.
The final mddev_put could have been called and the
mddev_delayed_delete is waiting for sysfs to let go so it can destroy
the kobj and mddev.
In this state there are a lot of changes that should not be attempted.
To to guard against this we:
- initialise mddev->all_mddevs in on last put so the state can be
easily detected.
- in md_attr_show and md_attr_store, check ->all_mddevs under
all_mddevs_lock and mddev_get the mddev if it still appears to
be active.
This means that if we get to sysfs as the mddev is being deleted we
will get -EBUSY.
rdev_attr_store and rdev_attr_show are similar but already have
sufficient protection. They check that rdev->mddev still points to
mddev after taking mddev_lock. As this is cleared before delayed
removal which can only be requested under the mddev_lock, this
ensure the rdev and mddev are still alive.
Signed-off-by: NeilBrown <neilb@suse.de>
We like md devices to disappear when they really are not needed.
However it is not possible to tell from the current state whether it
is needed or not. We can only tell from recent history of changes.
In particular immediately after we create an md device it looks very
similar to immediately after we have finished with it.
So we always preserve a newly created md device until something
significant happens. This state is stored in 'hold_active'.
The normal case is to keep it until an ioctl happens, as that will
normally either activate it, or explicitly de-activate it. If it
doesn't then it was probably created by mistake and it is now time to
get rid of it.
We can also modify an array via sysfs (instead of via ioctl) and we
currently treat any change via sysfs like an ioctl as a sign that if
it now isn't more active, it should be destroyed.
However this is not appropriate as changes made via sysfs are more
gradual so we should look for a more definitive change.
So this patch only clears 'hold_active' from UNTIL_IOCTL to clear when
the array_state is changed via sysfs. Other changes via sysfs
are ignored.
Signed-off-by: NeilBrown <neilb@suse.de>
Page attributes are set using __set_bit rather than set_bit as
it normally called under a spinlock so the extra atomicity is not
needed.
However there are two places where we might set or clear page
attributes without holding the spinlock.
So add the spinlock in those cases.
This might be the cause of occasional reports that bits a aren't
getting clear properly - theory is that BITMAP_PAGE_PENDING gets lost
when BITMAP_PAGE_NEEDWRITE is set or cleared. This is an
inconvenience, not a threat to data safety.
Signed-off-by: NeilBrown <neilb@suse.de>
All updates that occur under STRIPE_ACTIVE should be globally visible
when STRIPE_ACTIVE clears. test_and_set_bit() implies a barrier, but
clear_bit() does not.
This is suitable for 3.1-stable.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: stable@kernel.org
When the number of failed devices exceeds the allowed number
we must abort any active parity operations (checks or updates) as they
are no longer meaningful, and can lead to a BUG_ON in
handle_parity_checks6.
This bug was introduce by commit 6c0069c0ae
in 2.6.29.
Reported-by: Manish Katiyar <mkatiyar@gmail.com>
Tested-by: Manish Katiyar <mkatiyar@gmail.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: stable@kernel.org
since it uses the module facilities.
Reported-by: Witold Baryluk <baryluk@smp.if.uj.edu.pl>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For the files which are not themselves modular, we can change
them to include only the smaller export.h since all they are
doing is looking for EXPORT_SYMBOL.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
Revert "tracing: Include module.h in define_trace.h"
irq: don't put module.h into irq.h for tracking irqgen modules.
bluetooth: macroize two small inlines to avoid module.h
ip_vs.h: fix implicit use of module_get/module_put from module.h
nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
include: replace linux/module.h with "struct module" wherever possible
include: convert various register fcns to macros to avoid include chaining
crypto.h: remove unused crypto_tfm_alg_modname() inline
uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
pm_runtime.h: explicitly requires notifier.h
linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
miscdevice.h: fix up implicit use of lists and types
stop_machine.h: fix implicit use of smp.h for smp_processor_id
of: fix implicit use of errno.h in include/linux/of.h
of_platform.h: delete needless include <linux/module.h>
acpi: remove module.h include from platform/aclinux.h
miscdevice.h: delete unnecessary inclusion of module.h
device_cgroup.h: delete needless include <linux/module.h>
net: sch_generic remove redundant use of <linux/module.h>
net: inet_timewait_sock doesnt need <linux/module.h>
...
Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in
- drivers/media/dvb/frontends/dibx000_common.c
- drivers/media/video/{mt9m111.c,ov6650.c}
- drivers/mfd/ab3550-core.c
- include/linux/dmaengine.h
* 'for-3.2/core' of git://git.kernel.dk/linux-block: (29 commits)
block: don't call blk_drain_queue() if elevator is not up
blk-throttle: use queue_is_locked() instead of lockdep_is_held()
blk-throttle: Take blkcg->lock while traversing blkcg->policy_list
blk-throttle: Free up policy node associated with deleted rule
block: warn if tag is greater than real_max_depth.
block: make gendisk hold a reference to its queue
blk-flush: move the queue kick into
blk-flush: fix invalid BUG_ON in blk_insert_flush
block: Remove the control of complete cpu from bio.
block: fix a typo in the blk-cgroup.h file
block: initialize the bounce pool if high memory may be added later
block: fix request_queue lifetime handling by making blk_queue_cleanup() properly shutdown
block: drop @tsk from attempt_plug_merge() and explain sync rules
block: make get_request[_wait]() fail if queue is dead
block: reorganize throtl_get_tg() and blk_throtl_bio()
block: reorganize queue draining
block: drop unnecessary blk_get/put_queue() in scsi_cmd_ioctl() and blk_get_tg()
block: pass around REQ_* flags instead of broken down booleans during request alloc/free
block: move blk_throtl prototypes to block/blk.h
block: fix genhd refcounting in blkio_policy_parse_and_set()
...
Fix up trivial conflicts due to "mddev_t" -> "struct mddev" conversion
and making the request functions be of type "void" instead of "int" in
- drivers/md/{faulty.c,linear.c,md.c,md.h,multipath.c,raid0.c,raid1.c,raid10.c,raid5.c}
- drivers/staging/zram/zram_drv.c
These files were getting the defines for EXPORT_SYMBOL because
device.h was including module.h. But we are going to put an
end to that. So add the proper export.h include now.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
A pending cleanup will mean that module.h won't be implicitly
everywhere anymore. Make sure the modular drivers in md dir
are actually calling out for <module.h> explicitly in advance.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
When devices in a RAID array are not in-sync, they are supposed to be
reported as such in the status output as an 'a' character, which means
"alive, but not in-sync". But when the entire array is rebuilt 'A' is
being used, which is incorrect. This patch corrects this to 'a'.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Allow userspace dm log implementations to register their log device so it
is no longer missing from the list of device dependencies.
When device mapper targets use a device they normally call dm_get_device
which includes it in the device list returned to userspace applications
such as LVM through the DM_TABLE_DEPS ioctl. Userspace log devices
don't use dm_get_device as userspace opens them so they are missing from
the list of dependencies.
This patch extends the DM_ULOG_CTR operation to allow userspace to
respond with the name of the log device (if appropriate) to be
registered via 'dm_get_device'. DM_ULOG_REQUEST_VERSION is incremented.
This is backwards compatible. If the kernel and userspace log server
have both been updated, the new information will be passed down to the
kernel and the device will be registered. If the kernel is new, but
the log server is old, the log server will not pass down any device
information and the kernel will simply bypass the device registration
as before. If the kernel is old but the log server is new, the log
server will see the old version number and not pass the device info.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Fix comments: clustered-disk needs a hyphen not an underscore.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Initial EXPERIMENTAL implementation of device-mapper thin provisioning
with snapshot support. The 'thin' target is used to create instances of
the virtual devices that are hosted in the 'thin-pool' target. The
thin-pool target provides data sharing among devices. This sharing is
made possible using the persistent-data library in the previous patch.
The main highlight of this implementation, compared to the previous
implementation of snapshots, is that it allows many virtual devices to
be stored on the same data volume, simplifying administration and
allowing sharing of data between volumes (thus reducing disk usage).
Another big feature is support for arbitrary depth of recursive
snapshots (snapshots of snapshots of snapshots ...). The previous
implementation of snapshots did this by chaining together lookup tables,
and so performance was O(depth). This new implementation uses a single
data structure so we don't get this degradation with depth.
For further information and examples of how to use this, please read
Documentation/device-mapper/thin-provisioning.txt
Signed-off-by: Joe Thornber <thornber@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The persistent-data library offers a re-usable framework for the storage
and management of on-disk metadata in device-mapper targets.
It's used by the thin-provisioning target in the next patch and in an
upcoming hierarchical storage target.
For further information, please read
Documentation/device-mapper/persistent-data.txt
Signed-off-by: Joe Thornber <thornber@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
The dm-bufio interface allows you to do cached I/O on devices,
holding recently-read blocks in memory and performing delayed writes.
We don't use buffer cache or page cache already present in the kernel, because:
* we need to handle block sizes larger than a page
* we can't allocate memory to perform reads or we'd have deadlocks
Currently, when a cache is required, we limit its size to a fraction of
available memory. Usage can be viewed and changed in
/sys/module/dm_bufio/parameters/ .
The first user is thin provisioning, but more dm users are planned.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Introduce DM_TARGET_IMMUTABLE to indicate that the target type cannot be mixed
with any other target type, and once loaded into a device, it cannot be
replaced with a table containing a different type.
The thin provisioning pool device will use this.
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Add a target feature flag DM_TARGET_ALWAYS_WRITEABLE to indicate that a target
does not support read-only mode.
The initial implementation of the thin provisioning target uses this.
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Introduce the concept of a singleton table which contains exactly one target.
If a target type sets the DM_TARGET_SINGLETON feature bit device-mapper
will ensure that any table that includes that target contains no others.
The thin provisioning pool target uses this.
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This patch introduces dm_kcopyd_zero() to make it easy to use
kcopyd to write zeros into the requested areas instead
instead of copying. It is implemented by passing a NULL
copying source to dm_kcopyd_copy().
The forthcoming thin provisioning target uses this.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Since set_current_state() contains a memory barrier in it,
an additional barrier isn't needed.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
printk_ratelimit() shares global ratelimiting state with all
other subsystems, so its usage is discouraged. Instead,
define and use dm's local state.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Allow QUEUE_FLAG_NONROT to propagate up the device stack if all
underlying devices are non-rotational. Tools like ureadahead will
schedule IOs differently based on the rotational flag.
With this patch, I see boot time go from 7.75 s to 7.46 s on my device.
Suggested-by: J. Richard Barnette <jrbarnette@chromium.org>
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Jens Axboe <jaxboe@fusionio.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: dm-devel@redhat.com
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
This is a fairly serious bug in RAID10.
When a RAID10 array is degraded and a hot-spare is activated, the
spare does not take up the empty slot, but rather replaces the first
working device.
This is likely to make the array non-functional. It would normally
be possible to recover the data, but that would need care and is not
guaranteed.
This bug was introduced in commit
2bb77736ae
which first appeared in 3.1.
Cc: stable@kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
In 3.0 we changed the way recovery_disabled was handle so that instead
of testing against zero, we test an mddev-> value against a conf->
value.
Two problems:
1/ one place in raid1 was missed and still sets to '1'.
2/ We didn't explicitly set the conf-> value at array creation
time.
It defaulted to '0' just like the mddev value does so they
could appear equal and thus disable recovery.
This did not affect normal 'md' as it calls bind_rdev_to_array
which changes the mddev value. However the dmraid interface
doesn't call this and so doesn't change ->recovery_disabled; so at
array start all recovery is incorrectly disabled.
So initialise the 'conf' value to one less that the mddev value, so
the will only be the same when explicitly set that way.
Reported-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
This bug was introduced in 415e72d034
which was in 2.6.36.
There is a small window of time between when a device fails and when
it is removed from the array. During this time we might still read
from it, but we won't write to it - so it is possible that we could
read stale data.
We didn't need the test of 'Faulty' before because the test on
In_sync is sufficient. Since we started allowing reads from the early
part of non-In_sync devices we need a test on Faulty too.
This is suitable for any kernel from 2.6.36 onwards, though the patch
might need a bit of tweaking in 3.0 and earlier.
Cc: stable@kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
bio originally has the functionality to set the complete cpu, but
it is broken.
Chirstoph said that "This code is unused, and from the all the
discussions lately pretty obviously broken. The only thing keeping
it serves is creating more confusion and possibly more bugs."
And Jens replied with "We can kill bio_set_completion_cpu(). I'm fine
with leaving cpu control to the request based drivers, they are the
only ones that can toggle the setting anyway".
So this patch tries to remove all the work of controling complete cpu
from a bio.
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Fix memory leak introduced by commit a6e50b409d
(dm snapshot: skip reading origin when overwriting complete chunk).
When allocating a set of jobs from kc->job_pool, job->master_job must be
set (to point to itself) so that the mempool item gets freed when the
master_job completes.
master_job was introduced by commit c6ea41fbbe
(dm kcopyd: preallocate sub jobs to avoid deadlock)
Reported-by: Michael Leun <ml@newton.leun.net>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
If an incremental recovery was interrupted, a subsequent
re-add will result in a full recovery, even though an
incremental should be possible (seen with raid1).
Solve this problem by not updating the superblock on the
recovering device until array is not degraded any longer.
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrei Warkentin <andreiw@vmware.com>
Signed-off-by: NeilBrown <neilb@suse.de>
When we add a device to an active array it can be meaningful to set
the 'insync' flag. This indicates that the device is in-sync with the
array except for locations recorded in the bitmap.
A bitmap-based recovery can then bring it completely in-sync.
Internally we move that flag to 'saved_raid_disk' but forgot to clear
In_sync like we do in add_new_disk.
So clear In_sync after moving its value to saved_raid_disk.
Reported-by: Andrei Warkentin <andreiw@vmware.com>
Signed-off-by: NeilBrown <neilb@suse.de>
RAID1 and RAID10 handle write requests by queuing them for handling by
a separate thread. This is because when a write-intent-bitmap is
active we might need to update the bitmap first, so it is good to
queue a lot of writes, then do one big bitmap update for them all.
However writeback request devices to appear to be congested after a
while so it can make some guesstimate of throughput. The infinite
queue defeats that (note that RAID5 has already has a finite queue so
it doesn't suffer from this problem).
So impose a limit on the number of pending write requests. By default
it is 1024 which seems to be generally suitable. Make it configurable
via module option just in case someone finds a regression.
Signed-off-by: NeilBrown <neilb@suse.de>
NeilBrown