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2015-07-25Merge tag 'md/4.2-fixes' of git://neil.brown.name/mdLinus Torvalds
Pull md fixes from Neil Brown: "Some md fixes for 4.2 Several are tagged for -stable. A few aren't because they are not very, serious or because they are in the 'experimental' cluster code" * tag 'md/4.2-fixes' of git://neil.brown.name/md: md/raid5: clear R5_NeedReplace when no longer needed. Fix read-balancing during node failure md-cluster: fix bitmap sub-offset in bitmap_read_sb md: Return error if request_module fails and returns positive value md: Skip cluster setup in case of error while reading bitmap md/raid1: fix test for 'was read error from last working device'. md: Skip cluster setup for dm-raid md: flush ->event_work before stopping array. md/raid10: always set reshape_safe when initializing reshape_position. md/raid5: avoid races when changing cache size.
2015-07-24md: Return error if request_module fails and returns positive valueGoldwyn Rodrigues
request_module() can return 256 (process exited) in some cases, which is not as specified in the documentation before the request_module() definition. Convert the error to -ENOENT. The positive error number results in bitmap_create() returning a value that is meant to be an error but doesn't look like one, so it is dereferenced as a point and causes a crash. (not needed for stable as this is "experimental" code) Fixes: edb39c9deda8 ("Introduce md_cluster_operations to handle cluster functions") Signed-off-By: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: NeilBrown <neilb@suse.com>
2015-07-22md: flush ->event_work before stopping array.NeilBrown
The 'event_work' worker used by dm-raid may still be running when the array is stopped. This can result in an oops. So flush the workqueue on which it is run after detaching and before destroying the device. Reported-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: NeilBrown <neilb@suse.com> Cc: stable@vger.kernel.org (2.6.38+ please delay 2 weeks after -final release) Fixes: 9d09e663d550 ("dm: raid456 basic support")
2015-07-05Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull more vfs updates from Al Viro: "Assorted VFS fixes and related cleanups (IMO the most interesting in that part are f_path-related things and Eric's descriptor-related stuff). UFS regression fixes (it got broken last cycle). 9P fixes. fs-cache series, DAX patches, Jan's file_remove_suid() work" [ I'd say this is much more than "fixes and related cleanups". The file_table locking rule change by Eric Dumazet is a rather big and fundamental update even if the patch isn't huge. - Linus ] * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (49 commits) 9p: cope with bogus responses from server in p9_client_{read,write} p9_client_write(): avoid double p9_free_req() 9p: forgetting to cancel request on interrupted zero-copy RPC dax: bdev_direct_access() may sleep block: Add support for DAX reads/writes to block devices dax: Use copy_from_iter_nocache dax: Add block size note to documentation fs/file.c: __fget() and dup2() atomicity rules fs/file.c: don't acquire files->file_lock in fd_install() fs:super:get_anon_bdev: fix race condition could cause dev exceed its upper limitation vfs: avoid creation of inode number 0 in get_next_ino namei: make set_root_rcu() return void make simple_positive() public ufs: use dir_pages instead of ufs_dir_pages() pagemap.h: move dir_pages() over there remove the pointless include of lglock.h fs: cleanup slight list_entry abuse xfs: Correctly lock inode when removing suid and file capabilities fs: Call security_ops->inode_killpriv on truncate fs: Provide function telling whether file_remove_privs() will do anything ...
2015-06-29Merge tag 'md/4.2' of git://neil.brown.name/mdLinus Torvalds
Pull md updates from Neil Brown: "A mixed bag - a few bug fixes - some performance improvement that decrease lock contention - some clean-up Nothing major" * tag 'md/4.2' of git://neil.brown.name/md: md: clear Blocked flag on failed devices when array is read-only. md: unlock mddev_lock on an error path. md: clear mddev->private when it has been freed. md: fix a build warning md/raid5: ignore released_stripes check md/raid5: per hash value and exclusive wait_for_stripe md/raid5: split wait_for_stripe and introduce wait_for_quiescent wait: introduce wait_event_exclusive_cmd md: convert to kstrto*() md/raid10: make sync_request_write() call bio_copy_data()
2015-06-26drivers/md/md.c: use strreplace()Rasmus Villemoes
There's no point in starting over when we meet a '/'. This also eliminates a stack variable and a little .text. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-25md: clear Blocked flag on failed devices when array is read-only.Neil Brown
The Blocked flag indicates that a device has failed but that this fact hasn't been recorded in the metadata yet. Writes to such devices cannot be allowed until the metadata has been updated. On a read-only array, the Blocked flag will never be cleared. This prevents the device being removed from the array. If the metadata is being handled by the kernel (i.e. !mddev->external), then we can be sure that if the array is switch to writable, then a metadata update will happen and will record the failure. So we don't need the flag set. If metadata is externally managed, it is upto the external manager to clear the 'blocked' flag. Reported-by: XiaoNi <xni@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de>
2015-06-25md: unlock mddev_lock on an error path.NeilBrown
This error path retuns while still holding the lock - bad. Fixes: 6791875e2e53 ("md: make reconfig_mutex optional for writes to md sysfs files.") Cc: stable@vger.kernel.org (v4.0+) Signed-off-by: NeilBrown <neilb@suse.com>
2015-06-25md: clear mddev->private when it has been freed.NeilBrown
If ->private is set when ->run is called, it is assumed to be a 'config' prepared as part of 'reshape'. So it is important when we free that config, that we also clear ->private. This is not often a problem as the mddev will normally be discarded shortly after the config us freed. However if an 'assemble' races with a final close, the assemble can use the old mddev which has a stale ->private. This leads to any of various sorts of crashes. So clear ->private after calling ->free(). Reported-by: Nate Clark <nate@neworld.us> Cc: stable@vger.kernel.org (v4.0+) Fixes: afa0f557cb15 ("md: rename ->stop to ->free") Signed-off-by: NeilBrown <neilb@suse.com>
2015-06-23vfs: add file_path() helperMiklos Szeredi
Turn d_path(&file->f_path, ...); into file_path(file, ...); Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-17md: fix a build warningFiro Yang
Warning like this: drivers/md/md.c: In function "update_array_info": drivers/md/md.c:6394:26: warning: logical not is only applied to the left hand side of comparison [-Wlogical-not-parentheses] !mddev->persistent != info->not_persistent|| Fix it as Neil Brown said: mddev->persistent != !info->not_persistent || Signed-off-by: Firo Yang <firogm@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
2015-06-17md: convert to kstrto*()Alexey Dobriyan
Convert away from deprecated simple_strto*() functions. Add "fit into sector_t" checks. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
2015-06-12md: make sure MD_RECOVERY_DONE is clear before starting recovery/resyncNeilBrown
MD_RECOVERY_DONE is normally cleared by md_check_recovery after a resync etc finished. However it is possible for raid5_start_reshape to race and start a reshape before MD_RECOVERY_DONE is cleared. This can lean to multiple reshapes running at the same time, which isn't good. To make sure it is cleared before starting a reshape, and also clear it when reaping a thread, just to be safe. Signed-off-by: NeilBrown <neilb@suse.de>
2015-06-12md: Close race when setting 'action' to 'idle'.NeilBrown
Checking ->sync_thread without holding the mddev_lock() isn't really safe, even after flushing the workqueue which ensures md_start_sync() has been run. While this code is waiting for the lock, md_check_recovery could reap the thread itself, and then start another thread (e.g. recovery might finish, then reshape starts). When this thread gets the lock md_start_sync() hasn't run so it doesn't get reaped, but MD_RECOVERY_RUNNING gets cleared. This allows two threads to start which leads to confusion. So don't both if MD_RECOVERY_RUNNING isn't set, but if it is do the flush and the test and the reap all under the mddev_lock to avoid any race with md_check_recovery. Signed-off-by: NeilBrown <neilb@suse.de> Fixes: 6791875e2e53 ("md: make reconfig_mutex optional for writes to md sysfs files.") Cc: stable@vger.kernel.org (v4.0+)
2015-06-12md: don't return 0 from array_state_storeNeilBrown
Returning zero from a 'store' function is bad. The return value should be either len length of the string or an error. So use 'len' if 'err' is zero. Fixes: 6791875e2e53 ("md: make reconfig_mutex optional for writes to md sysfs files.") Signed-off-by: NeilBrown <neilb@suse.de> Cc: stable@vger.kernel (v4.0+)
2015-05-29Merge tag 'md/4.1-rc5-fixes' of git://neil.brown.name/mdLinus Torvalds
Pull m,ore md bugfixes gfrom Neil Brown: "Assorted fixes for new RAID5 stripe-batching functionality. Unfortunately this functionality was merged a little prematurely. The necessary testing and code review is now complete (or as complete as it can be) and to code passes a variety of tests and looks quite sensible. Also a fix for some recent locking changes - a race was introduced which causes a reshape request to sometimes fail. No data safety issues" * tag 'md/4.1-rc5-fixes' of git://neil.brown.name/md: md: fix race when unfreezing sync_action md/raid5: break stripe-batches when the array has failed. md/raid5: call break_stripe_batch_list from handle_stripe_clean_event md/raid5: be more selective about distributing flags across batch. md/raid5: add handle_flags arg to break_stripe_batch_list. md/raid5: duplicate some more handle_stripe_clean_event code in break_stripe_batch_list md/raid5: remove condition test from check_break_stripe_batch_list. md/raid5: Ensure a batch member is not handled prematurely. md/raid5: close race between STRIPE_BIT_DELAY and batching. md/raid5: ensure whole batch is delayed for all required bitmap updates.
2015-05-28md: fix race when unfreezing sync_actionNeilBrown
A recent change removed the need for locking around writing to "sync_action" (and various other places), but introduced a subtle race. When e.g. setting 'reshape' on a 'frozen' array, the 'frozen' flag is cleared before 'reshape' is set, so the md thread can get in and start trying recovery - which isn't wanted. So instead of clearing MD_RECOVERY_FROZEN for any command except 'frozen', only clear it when each specific command is parsed. This allows the handling of 'reshape' to clear the bit while a lock is held. Also remove some places where we set MD_RECOVERY_NEEDED, as it is always set on non-error exit of the function. Signed-off-by: NeilBrown <neilb@suse.de> Fixes: 6791875e2e53 ("md: make reconfig_mutex optional for writes to md sysfs files.")
2015-05-09Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block fixes from Jens Axboe: "A collection of fixes since the merge window; - fix for a double elevator module release, from Chao Yu. Ancient bug. - the splice() MORE flag fix from Christophe Leroy. - a fix for NVMe, fixing a patch that went in in the merge window. From Keith. - two fixes for blk-mq CPU hotplug handling, from Ming Lei. - bdi vs blockdev lifetime fix from Neil Brown, fixing and oops in md. - two blk-mq fixes from Shaohua, fixing a race on queue stop and a bad merge issue with FUA writes. - division-by-zero fix for writeback from Tejun. - a block bounce page accounting fix, making sure we inc/dec after bouncing so that pre/post IO pages match up. From Wang YanQing" * 'for-linus' of git://git.kernel.dk/linux-block: splice: sendfile() at once fails for big files blk-mq: don't lose requests if a stopped queue restarts blk-mq: fix FUA request hang block: destroy bdi before blockdev is unregistered. block:bounce: fix call inc_|dec_zone_page_state on different pages confuse value of NR_BOUNCE elevator: fix double release of elevator module writeback: use |1 instead of +1 to protect against div by zero blk-mq: fix CPU hotplug handling blk-mq: fix race between timeout and CPU hotplug NVMe: Fix VPD B0 max sectors translation
2015-04-27block: destroy bdi before blockdev is unregistered.NeilBrown
Because of the peculiar way that md devices are created (automatically when the device node is opened), a new device can be created and registered immediately after the blk_unregister_region(disk_devt(disk), disk->minors); call in del_gendisk(). Therefore it is important that all visible artifacts of the previous device are removed before this call. In particular, the 'bdi'. Since: commit c4db59d31e39ea067c32163ac961e9c80198fd37 Author: Christoph Hellwig <hch@lst.de> fs: don't reassign dirty inodes to default_backing_dev_info moved the device_unregister(bdi->dev); call from bdi_unregister() to bdi_destroy() it has been quite easy to lose a race and have a new (e.g.) "md127" be created after the blk_unregister_region() call and before bdi_destroy() is ultimately called by the final 'put_disk', which must come after del_gendisk(). The new device finds that the bdi name is already registered in sysfs and complains > [ 9627.630029] WARNING: CPU: 18 PID: 3330 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x5a/0x70() > [ 9627.630032] sysfs: cannot create duplicate filename '/devices/virtual/bdi/9:127' We can fix this by moving the bdi_destroy() call out of blk_release_queue() (which can happen very late when a refcount reaches zero) and into blk_cleanup_queue() - which happens exactly when the md device driver calls it. Then it is only necessary for md to call blk_cleanup_queue() before del_gendisk(). As loop.c devices are also created on demand by opening the device node, we make the same change there. Fixes: c4db59d31e39ea067c32163ac961e9c80198fd37 Reported-by: Azat Khuzhin <a3at.mail@gmail.com> Cc: Christoph Hellwig <hch@lst.de> Cc: stable@vger.kernel.org (v4.0) Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-04-21md: allow resync to go faster when there is competing IO.NeilBrown
When md notices non-sync IO happening while it is trying to resync (or reshape or recover) it slows down to the set minimum. The default minimum might have made sense many years ago but the drives have become faster. Changing the default to match the times isn't really a long term solution. This patch changes the code so that instead of waiting until the speed has dropped to the target, it just waits until pending requests have completed. This means that the delay inserted is a function of the speed of the devices. Testing shows that: - for some loads, the resync speed is unchanged. For those loads increasing the minimum doesn't change the speed either. So this is a good result. To increase resync speed under such loads we would probably need to increase the resync window size. - for other loads, resync speed does increase to a reasonable fraction (e.g. 20%) of maximum possible, and throughput of the load only drops a little bit (e.g. 10%) - for other loads, throughput of the non-sync load drops quite a bit more. These seem to be latency-sensitive loads. So it isn't a perfect solution, but it is mostly an improvement. Signed-off-by: NeilBrown <neilb@suse.de>
2015-04-21md: remove 'go_faster' option from ->sync_request()NeilBrown
This option is not well justified and testing suggests that it hardly ever makes any difference. The comment suggests there might be a need to wait for non-resync activity indicated by ->nr_waiting, however raise_barrier() already waits for all of that. So just remove it to simplify reasoning about speed limiting. This allows us to remove a 'FIXME' comment from raid5.c as that never used the flag. Signed-off-by: NeilBrown <neilb@suse.de>
2015-04-21md: don't require sync_min to be a multiple of chunk_size.NeilBrown
There is really no need for sync_min to be a multiple of chunk_size, and values read from here often aren't. That means you cannot read a value and expect to be able to write it back later. So remove the chunk_size check, and round down to a multiple of 4K, to be sure everything works with 4K-sector devices. Signed-off-by: NeilBrown <neilb@suse.de>
2015-04-21Merge branch 'cluster' into for-nextNeilBrown
2015-04-21md-cluster: re-add capabilitiesGoldwyn Rodrigues
When "re-add" is writted to /sys/block/mdXX/md/dev-YYY/state, the clustered md: 1. Sends RE_ADD message with the desc_nr. Nodes receiving the message clear the Faulty bit in their respective rdev->flags. 2. The node initiating re-add, gathers the bitmaps of all nodes and copies them into the local bitmap. It does not clear the bitmap from which it is copying. 3. Initiating node schedules a md recovery to sync the devices. Signed-off-by: Guoqing Jiang <gqjiang@suse.com> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: NeilBrown <neilb@suse.de>
2015-04-21md: re-add a failed diskGoldwyn Rodrigues
This adds the capability of re-adding a failed disk by writing "re-add" to /sys/block/mdXX/md/dev-YYY/state. This facilitates adding disks which have encountered a temporary error such as a network disconnection/hiccup in an iSCSI device, or a SAN cable disconnection which has been restored. In such a situation, you do not need to remove and re-add the device. Writing re-add to the failed device's state would add it again to the array and perform the recovery of only the blocks which were written after the device failed. This works for generic md, and is not related to clustering. However, this patch is to ease re-add operations listed above in clustering environments. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: NeilBrown <neilb@suse.de>
2015-04-21md-cluster: remove capabilitiesGoldwyn Rodrigues
This adds "remove" capabilities for the clustered environment. When a user initiates removal of a device from the array, a REMOVE message with disk number in the array is sent to all the nodes which kick the respective device in their own array. This facilitates the removal of failed devices. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: NeilBrown <neilb@suse.de>
2015-04-21md: Export and rename find_rdev_nr_rcuGoldwyn Rodrigues
This is required by the clustering module (patches to follow) to find the device to remove or re-add. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: NeilBrown <neilb@suse.de>
2015-04-21md: Export and rename kick_rdev_from_arrayGoldwyn Rodrigues
This export is required for clustering module in order to co-ordinate remove/readd a rdev from all nodes. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: NeilBrown <neilb@suse.de>
2015-04-08md: fix md io stats accounting brokenGu Zheng
Simon reported the md io stats accounting issue: " I'm seeing "iostat -x -k 1" print this after a RAID1 rebuild on 4.0-rc5. It's not abnormal other than it's 3-disk, with one being SSD (sdc) and the other two being write-mostly: Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util sda 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 sdb 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 sdc 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 md0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 345.00 0.00 0.00 0.00 0.00 100.00 md2 0.00 0.00 0.00 0.00 0.00 0.00 0.00 58779.00 0.00 0.00 0.00 0.00 100.00 md1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 12.00 0.00 0.00 0.00 0.00 100.00 " The cause is commit "18c0b223cf9901727ef3b02da6711ac930b4e5d4" uses the generic_start_io_acct to account the disk stats rather than the open code, but it also introduced the increase to .in_flight[rw] which is needless to md. So we re-use the open code here to fix it. Reported-by: Simon Kirby <sim@hostway.ca> Cc: <stable@vger.kernel.org> 3.19 Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Signed-off-by: NeilBrown <neilb@suse.de>
2015-03-20md: Fix stray --cluster-confirm crashGoldwyn Rodrigues
A --cluster-confirm without an --add (by another node) can crash the kernel. Fix it by guarding it using a state. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Signed-off-by: NeilBrown <neilb@suse.de>
2015-03-20md: fix problems with freeing private data after ->run failure.NeilBrown
If ->run() fails, it can either free the data structures it allocated, or leave that task to ->free() which will be called on failures. However: md.c calls ->free() even if ->private_data is NULL, which causes problems in some personalities. raid0.c frees the data, but doesn't clear ->private_data, which will become a problem when we fix md.c So better fix both these issues at once. Reported-by: Richard W.M. Jones <rjones@redhat.com> Fixes: 5aa61f427e4979be733e4847b9199ff9cc48a47e URL: https://bugzilla.kernel.org/show_bug.cgi?id=94381 Signed-off-by: NeilBrown <neilb@suse.de>
2015-02-25md: fix error paths from bitmap_create.NeilBrown
Recent change to bitmap_create mishandles errors. In particular a failure doesn't alway cause 'err' to be set. Signed-off-by: NeilBrown <neilb@suse.de>
2015-02-25md: mark some attributes as pre-allocNeilBrown
Since __ATTR_PREALLOC was introduced in v3.19-rc1~78^2~18 it can now be used by md. This ensure that writing to these sysfs attributes will never block due to a memory allocation. Such blocking could become a deadlock if mdmon is trying to reconfigure an array after a failure prior to re-enabling writes. Signed-off-by: NeilBrown <neilb@suse.de>
2015-02-23Add new disk to clustered arrayGoldwyn Rodrigues
Algorithm: 1. Node 1 issues mdadm --manage /dev/mdX --add /dev/sdYY which issues ioctl(ADD_NEW_DISC with disc.state set to MD_DISK_CLUSTER_ADD) 2. Node 1 sends NEWDISK with uuid and slot number 3. Other nodes issue kobject_uevent_env with uuid and slot number (Steps 4,5 could be a udev rule) 4. In userspace, the node searches for the disk, perhaps using blkid -t SUB_UUID="" 5. Other nodes issue either of the following depending on whether the disk was found: ioctl(ADD_NEW_DISK with disc.state set to MD_DISK_CANDIDATE and disc.number set to slot number) ioctl(CLUSTERED_DISK_NACK) 6. Other nodes drop lock on no-new-devs (CR) if device is found 7. Node 1 attempts EX lock on no-new-devs 8. If node 1 gets the lock, it sends METADATA_UPDATED after unmarking the disk as SpareLocal 9. If not (get no-new-dev lock), it fails the operation and sends METADATA_UPDATED 10. Other nodes understand if the device is added or not by reading the superblock again after receiving the METADATA_UPDATED message. Signed-off-by: Lidong Zhong <lzhong@suse.com> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2015-02-23Suspend writes in RAID1 if within rangeGoldwyn Rodrigues
If there is a resync going on, all nodes must suspend writes to the range. This is recorded in the suspend_info/suspend_list. If there is an I/O within the ranges of any of the suspend_info, should_suspend will return 1. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2015-02-23Send RESYNCING while performing resync start/stopGoldwyn Rodrigues
When a resync is initiated, RESYNCING message is sent to all active nodes with the range (lo,hi). When the resync is over, a RESYNCING message is sent with (0,0). A high sector value of zero indicates that the resync is over. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2015-02-23Reload superblock if METADATA_UPDATED is receivedGoldwyn Rodrigues
Re-reads the devices by invalidating the cache. Since we don't write to faulty devices, this is detected using events recorded in the devices. If it is old as compared to the mddev mark it is faulty. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2015-02-23metadata_update sends message to other nodesGoldwyn Rodrigues
- request to send a message - make changes to superblock - send messages telling everyone that the superblock has changed - other nodes all read the superblock - other nodes all ack the messages - updating node release the "I'm sending a message" resource. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2015-02-23bitmap_create returns bitmap pointerGoldwyn Rodrigues
This is done to have multiple bitmaps open at the same time. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2015-02-23Gather on-going resync information of other nodesGoldwyn Rodrigues
When a node joins, it does not know of other nodes performing resync. So, each node keeps the resync information in it's LVB. When a new node joins, it reads the LVB of each "online" bitmap. [TODO] The new node attempts to get the PW lock on other bitmap, if it is successful, it reads the bitmap and performs the resync (if required) on it's behalf. If the node does not get the PW, it requests CR and reads the LVB for the resync information. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2015-02-23Add node recovery callbacksGoldwyn Rodrigues
DLM offers callbacks when a node fails and the lock remastery is performed: 1. recover_prep: called when DLM discovers a node is down 2. recover_slot: called when DLM identifies the node and recovery can start 3. recover_done: called when all nodes have completed recover_slot recover_slot() and recover_done() are also called when the node joins initially in order to inform the node with its slot number. These slot numbers start from one, so we deduct one to make it start with zero which the cluster-md code uses. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2015-02-23Return MD_SB_CLUSTERED if mddev is clusteredGoldwyn Rodrigues
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2015-02-23Introduce md_cluster_infoGoldwyn Rodrigues
md_cluster_info stores the cluster information in the MD device. The join() is called when mddev detects it is a clustered device. The main responsibilities are: 1. Setup a DLM lockspace 2. Setup all initial locks such as super block locks and bitmap lock (will come later) The leave() clears up the lockspace and all the locks held. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2015-02-23Introduce md_cluster_operations to handle cluster functionsGoldwyn Rodrigues
This allows dynamic registering of cluster hooks. Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
2015-02-05md: make reconfig_mutex optional for writes to md sysfs files.NeilBrown
Rather than using mddev_lock() to take the reconfig_mutex when writing to any md sysfs file, we only take mddev_lock() in the particular _store() functions that require it. Admittedly this is most, but it isn't all. This also allows us to remove special-case handling for new_dev_store (in md_attr_store). Signed-off-by: NeilBrown <neilb@suse.de>
2015-02-05md: move mddev_lock and related to md.hNeilBrown
The one which is not inline (mddev_unlock) gets EXPORTed. This makes the locking available to personality modules so that it doesn't have to be imposed upon them. Signed-off-by: NeilBrown <neilb@suse.de>
2015-02-05md: use mddev->lock to protect updates to resync_{min,max}.NeilBrown
There are interdependencies between these two sysfs attributes and whether a resync is currently running. Rather than depending on reconfig_mutex to ensure no races when testing these interdependencies are met, use the spinlock. This will allow the mutex to be remove from protecting this code in a subsequent patch. Signed-off-by: NeilBrown <neilb@suse.de>
2015-02-05md: minor cleanup in safe_delay_store.NeilBrown
There isn't really much room for races with ->safemode_delay. But as I am trying to clean up any racy code and will soon be removing reconfig_mutex protection from most _store() functions: - only set mddev->safemode_delay once, to ensure no code can see an intermediate value - use safemode_timer to call md_safemode_timeout() rather than calling it directly, to ensure it never races with itself. Signed-off-by: NeilBrown <neilb@suse.de>
2015-02-05md: move GET_BITMAP_FILE ioctl out from mddev_lock.NeilBrown
It makes more sense to report bitmap_info->file, rather than bitmap->file (the later is only available once the array is active). With that change, use mddev->lock to protect bitmap_info being set to NULL, and we can call get_bitmap_file() without taking the mutex. Signed-off-by: NeilBrown <neilb@suse.de>
2015-02-05md: tidy up set_bitmap_fileNeilBrown
1/ delay setting mddev->bitmap_info.file until 'f' looks usable, so we don't have to unset it. 2/ Don't allow bitmap file to be set if bitmap_info.file is already set. Signed-off-by: NeilBrown <neilb@suse.de>