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path: root/fs/btrfs/disk-io.h
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2013-05-06btrfs: make static code static & remove dead codeEric Sandeen
Big patch, but all it does is add statics to functions which are in fact static, then remove the associated dead-code fallout. removed functions: btrfs_iref_to_path() __btrfs_lookup_delayed_deletion_item() __btrfs_search_delayed_insertion_item() __btrfs_search_delayed_deletion_item() find_eb_for_page() btrfs_find_block_group() range_straddles_pages() extent_range_uptodate() btrfs_file_extent_length() btrfs_scrub_cancel_devid() btrfs_start_transaction_lflush() btrfs_print_tree() is left because it is used for debugging. btrfs_start_transaction_lflush() and btrfs_reada_detach() are left for symmetry. ulist.c functions are left, another patch will take care of those. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06Btrfs: cleanup unused arguments of btrfs_csum_dataLiu Bo
Argument 'root' is no more used in btrfs_csum_data(). Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-04-29Btrfs: cleanup unused functionLiu Bo
btrfs_abort_devices() is no more used. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-01Btrfs: RAID5 and RAID6David Woodhouse
This builds on David Woodhouse's original Btrfs raid5/6 implementation. The code has changed quite a bit, blame Chris Mason for any bugs. Read/modify/write is done after the higher levels of the filesystem have prepared a given bio. This means the higher layers are not responsible for building full stripes, and they don't need to query for the topology of the extents that may get allocated during delayed allocation runs. It also means different files can easily share the same stripe. But, it does expose us to incorrect parity if we crash or lose power while doing a read/modify/write cycle. This will be addressed in a later commit. Scrub is unable to repair crc errors on raid5/6 chunks. Discard does not work on raid5/6 (yet) The stripe size is fixed at 64KiB per disk. This will be tunable in a later commit. Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12Btrfs: cleanup for btrfs_btree_balance_dirtyLiu Bo
- 'nr' is no more used. - btrfs_btree_balance_dirty() and __btrfs_btree_balance_dirty() can share a bunch of code. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-10-09Btrfs: make filesystem read-only when submitting barrier failsStefan Behrens
So far the return code of barrier_all_devices() is ignored, which means that errors are ignored. The result can be a corrupt filesystem which is not consistent. This commit adds code to evaluate the return code of barrier_all_devices(). The normal btrfs_error() mechanism is used to switch the filesystem into read-only mode when errors are detected. In order to decide whether barrier_all_devices() should return error or success, the number of disks that are allowed to fail the barrier submission is calculated. This calculation accounts for the worst RAID level of metadata, system and data. If single, dup or RAID0 is in use, a single disk error is already considered to be fatal. Otherwise a single disk error is tolerated. The calculation of the number of disks that are tolerated to fail the barrier operation is performed when the filesystem gets mounted, when a balance operation is started and finished, and when devices are added or removed. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
2012-08-28Btrfs: remove superblock writing after fatal errorStefan Behrens
With commit acce952b0, btrfs was changed to flag the filesystem with BTRFS_SUPER_FLAG_ERROR and switch to read-only mode after a fatal error happened like a write I/O errors of all mirrors. In such situations, on unmount, the superblock is written in btrfs_error_commit_super(). This is done with the intention to be able to evaluate the error flag on the next mount. A warning is printed in this case during the next mount and the log tree is ignored. The issue is that it is possible that the superblock points to a root that was not written (due to write I/O errors). The result is that the filesystem cannot be mounted. btrfsck also does not start and all the other btrfs-progs tools fail to start as well. However, mount -o recovery is working well and does the right things to recover the filesystem (i.e., don't use the log root, clear the free space cache and use the next mountable root that is stored in the root backup array). This patch removes the writing of the superblock when BTRFS_SUPER_FLAG_ERROR is set, and removes the handling of the error flag in the mount function. These lines can be used to reproduce the issue (using /dev/sdm): SCRATCH_DEV=/dev/sdm SCRATCH_MNT=/mnt echo 0 25165824 linear $SCRATCH_DEV 0 | dmsetup create foo ls -alLF /dev/mapper/foo mkfs.btrfs /dev/mapper/foo mount /dev/mapper/foo $SCRATCH_MNT echo bar > $SCRATCH_MNT/foo sync echo 0 25165824 error | dmsetup reload foo dmsetup resume foo ls -alF $SCRATCH_MNT touch $SCRATCH_MNT/1 ls -alF $SCRATCH_MNT sleep 35 echo 0 25165824 linear $SCRATCH_DEV 0 | dmsetup reload foo dmsetup resume foo sleep 1 umount $SCRATCH_MNT btrfsck /dev/mapper/foo dmsetup remove foo Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-07-10Btrfs: added helper to create new treesArne Jansen
This creates a brand new tree. Will be used to create the quota tree. Signed-off-by: Arne Jansen <sensille@gmx.net>
2012-05-30btrfs: Drop unused function btrfs_abort_devices()Asias He
1) This function is not used anywhere. 2) Using the blk_abort_queue() to abort the queue seems not correct. blk_abort_queue() is used for timeout handling (block/blk-timeout.c). Cc: Chris Mason <chris.mason@oracle.com> Cc: linux-btrfs@vger.kernel.org Cc: Jens Axboe <axboe@kernel.dk> Cc: linux-kernel@vger.kernel.org Signed-off-by: Asias He <asias@redhat.com>
2012-05-06Btrfs: avoid sleeping in verify_parent_transid while atomicChris Mason
verify_parent_transid needs to lock the extent range to make sure no IO is underway, and so it can safely clear the uptodate bits if our checks fail. But, a few callers are using it with spinlocks held. Most of the time, the generation numbers are going to match, and we don't want to switch to a blocking lock just for the error case. This adds an atomic flag to verify_parent_transid, and changes it to return EAGAIN if it needs to block to properly verifiy things. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-03-22btrfs: enhance transaction abort infrastructureJeff Mahoney
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
2012-03-22btrfs: return void in functions without error conditionsJeff Mahoney
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
2012-03-22btrfs: clean_tree_block should panic on observed memory corruption and ↵Jeff Mahoney
return void The only error condition in clean_tree_block is an accounting bug. Returning without modifying dirty_metadata_bytes and as if the cleaning as been performed may cause problems later so it should panic instead. It should probably be a BUG_ON but we have btrfs_panic now. Signed-off-by: Jeff Mahoney <jeffm@suse.com>
2012-01-08btrfs: take allocation of ->tree_root into open_ctree()Al Viro
now that we don't need it for sget() anymore... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-08btrfs: make open_ctree() return intAl Viro
It returns either ERR_PTR(-ve) or sb->s_fs_info. The latter can be found by caller just as well, TYVM, no need to return it. Just return -ve or 0... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-08btrfs: sanitizing ->fs_info, part 4Al Viro
A new helper: btrfs_alloc_root(fs_info); allocates btrfs_root and sets ->fs_info. All places allocating the suckers converted to it. At that point we *never* reassign ->fs_info of btrfs_root; it's set before anyone sees the address of newly allocated struct btrfs_root and never assigned anywhere else. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-11-06Merge branch 'for-chris' of git://github.com/sensille/linux into integrationChris Mason
Conflicts: fs/btrfs/ctree.h Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-11-06Btrfs: make sure to flush queued bios if write_cache_pages waitsChris Mason
write_cache_pages tries to build up a large bio to stuff down the pipe. But if it needs to wait for a page lock, it needs to make sure and send down any pending writes so we don't deadlock with anyone who has the page lock and is waiting for writeback of things inside the bio. Dave Sterba triggered this as a deadlock between the autodefrag code and the extent write_cache_pages Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-10-02btrfs: add READAHEAD extent buffer flagArne Jansen
Add a READAHEAD extent buffer flag. Add a function to trigger a read with this flag set. Changes v2: - use extent buffer flags instead of extent state flags Changes v5: - adapt to changed read_extent_buffer_pages interface - don't return eb from reada_tree_block_flagged if it has CORRUPT flag set Signed-off-by: Arne Jansen <sensille@gmx.net>
2011-07-27Btrfs: make a lockdep class for each rootChris Mason
This patch was originally from Tejun Heo. lockdep complains about the btrfs locking because we sometimes take btree locks from two different trees at the same time. The current classes are based only on level in the btree, which isn't enough information for lockdep to figure out if the lock is safe. This patch makes a class for each type of tree, and lumps all the FS trees that actually have files and directories into the same class. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-05-22Merge branch 'cleanups' of git://repo.or.cz/linux-2.6/btrfs-unstable into ↵Chris Mason
inode_numbers Conflicts: fs/btrfs/extent-tree.c fs/btrfs/free-space-cache.c fs/btrfs/inode.c fs/btrfs/tree-log.c Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-05-21btrfs: implement delayed inode items operationMiao Xie
Changelog V5 -> V6: - Fix oom when the memory load is high, by storing the delayed nodes into the root's radix tree, and letting btrfs inodes go. Changelog V4 -> V5: - Fix the race on adding the delayed node to the inode, which is spotted by Chris Mason. - Merge Chris Mason's incremental patch into this patch. - Fix deadlock between readdir() and memory fault, which is reported by Itaru Kitayama. Changelog V3 -> V4: - Fix nested lock, which is reported by Itaru Kitayama, by updating space cache inode in time. Changelog V2 -> V3: - Fix the race between the delayed worker and the task which does delayed items balance, which is reported by Tsutomu Itoh. - Modify the patch address David Sterba's comment. - Fix the bug of the cpu recursion spinlock, reported by Chris Mason Changelog V1 -> V2: - break up the global rb-tree, use a list to manage the delayed nodes, which is created for every directory and file, and used to manage the delayed directory name index items and the delayed inode item. - introduce a worker to deal with the delayed nodes. Compare with Ext3/4, the performance of file creation and deletion on btrfs is very poor. the reason is that btrfs must do a lot of b+ tree insertions, such as inode item, directory name item, directory name index and so on. If we can do some delayed b+ tree insertion or deletion, we can improve the performance, so we made this patch which implemented delayed directory name index insertion/deletion and delayed inode update. Implementation: - introduce a delayed root object into the filesystem, that use two lists to manage the delayed nodes which are created for every file/directory. One is used to manage all the delayed nodes that have delayed items. And the other is used to manage the delayed nodes which is waiting to be dealt with by the work thread. - Every delayed node has two rb-tree, one is used to manage the directory name index which is going to be inserted into b+ tree, and the other is used to manage the directory name index which is going to be deleted from b+ tree. - introduce a worker to deal with the delayed operation. This worker is used to deal with the works of the delayed directory name index items insertion and deletion and the delayed inode update. When the delayed items is beyond the lower limit, we create works for some delayed nodes and insert them into the work queue of the worker, and then go back. When the delayed items is beyond the upper bound, we create works for all the delayed nodes that haven't been dealt with, and insert them into the work queue of the worker, and then wait for that the untreated items is below some threshold value. - When we want to insert a directory name index into b+ tree, we just add the information into the delayed inserting rb-tree. And then we check the number of the delayed items and do delayed items balance. (The balance policy is above.) - When we want to delete a directory name index from the b+ tree, we search it in the inserting rb-tree at first. If we look it up, just drop it. If not, add the key of it into the delayed deleting rb-tree. Similar to the delayed inserting rb-tree, we also check the number of the delayed items and do delayed items balance. (The same to inserting manipulation) - When we want to update the metadata of some inode, we cached the data of the inode into the delayed node. the worker will flush it into the b+ tree after dealing with the delayed insertion and deletion. - We will move the delayed node to the tail of the list after we access the delayed node, By this way, we can cache more delayed items and merge more inode updates. - If we want to commit transaction, we will deal with all the delayed node. - the delayed node will be freed when we free the btrfs inode. - Before we log the inode items, we commit all the directory name index items and the delayed inode update. I did a quick test by the benchmark tool[1] and found we can improve the performance of file creation by ~15%, and file deletion by ~20%. Before applying this patch: Create files: Total files: 50000 Total time: 1.096108 Average time: 0.000022 Delete files: Total files: 50000 Total time: 1.510403 Average time: 0.000030 After applying this patch: Create files: Total files: 50000 Total time: 0.932899 Average time: 0.000019 Delete files: Total files: 50000 Total time: 1.215732 Average time: 0.000024 [1] http://marc.info/?l=linux-btrfs&m=128212635122920&q=p3 Many thanks for Kitayama-san's help! Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Reviewed-by: David Sterba <dave@jikos.cz> Tested-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Tested-by: Itaru Kitayama <kitayama@cl.bb4u.ne.jp> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-05-06btrfs: remove all unused functionsDavid Sterba
Remove static and global declarations and/or definitions. Reduces size of btrfs.ko by ~3.4kB. text data bss dec hex filename 402081 7464 200 409745 64091 btrfs.ko.base 398620 7144 200 405964 631cc btrfs.ko.remove-all Signed-off-by: David Sterba <dsterba@suse.cz>
2011-05-04btrfs: remove unused function prototypesDavid Sterba
function prototypes without a body Signed-off-by: David Sterba <dsterba@suse.cz>
2011-01-17Btrfs: forced readonly mounts on errorsliubo
This patch comes from "Forced readonly mounts on errors" ideas. As we know, this is the first step in being more fault tolerant of disk corruptions instead of just using BUG() statements. The major content: - add a framework for generating errors that should result in filesystems going readonly. - keep FS state in disk super block. - make sure that all of resource will be freed and released at umount time. - make sure that fter FS is forced readonly on error, there will be no more disk change before FS is corrected. For this, we should stop write operation. After this patch is applied, the conversion from BUG() to such a framework can happen incrementally. Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-05-25Btrfs: use async helpers for DIO write checksummingChris Mason
The async helper threads offload crc work onto all the CPUs, and make streaming writes much faster. This changes the O_DIRECT write code to use them. The only small complication was that we need to pass in the logical offset in the file for each bio, because we can't find it in the bio's pages. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-05-25Btrfs: Metadata ENOSPC handling for tree logYan, Zheng
Previous patches make the allocater return -ENOSPC if there is no unreserved free metadata space. This patch updates tree log code and various other places to propagate/handle the ENOSPC error. Signed-off-by: Yan Zheng <zheng.yan@oracle.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-03-24Btrfs: leave btree locks spinning more oftenChris Mason
btrfs_mark_buffer dirty would set dirty bits in the extent_io tree for the buffers it was dirtying. This may require a kmalloc and it was not atomic. So, anyone who called btrfs_mark_buffer_dirty had to set any btree locks they were holding to blocking first. This commit changes dirty tracking for extent buffers to just use a flag in the extent buffer. Now that we have one and only one extent buffer per page, this can be safely done without losing dirty bits along the way. This also introduces a path->leave_spinning flag that callers of btrfs_search_slot can use to indicate they will properly deal with a path returned where all the locks are spinning instead of blocking. Many of the btree search callers now expect spinning paths, resulting in better btree concurrency overall. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-02-12Btrfs: make a lockdep class for the extent buffer locksChris Mason
Btrfs is currently using spin_lock_nested with a nested value based on the tree depth of the block. But, this doesn't quite work because the max tree depth is bigger than what spin_lock_nested can deal with, and because locks are sometimes taken before the level field is filled in. The solution here is to use lockdep_set_class_and_name instead, and to set the class before unlocking the pages when the block is read from the disk and just after init of a freshly allocated tree block. btrfs_clear_path_blocking is also changed to take the locks in the proper order, and it also makes sure all the locks currently held are properly set to blocking before it tries to retake the spinlocks. Otherwise, lockdep gets upset about bad lock orderin. The lockdep magic cam from Peter Zijlstra <peterz@infradead.org> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-01-21Btrfs: fix tree logs parallel syncYan Zheng
To improve performance, btrfs_sync_log merges tree log sync requests. But it wrongly merges sync requests for different tree logs. If multiple tree logs are synced at the same time, only one of them actually gets synced. This patch has following changes to fix the bug: Move most tree log related fields in btrfs_fs_info to btrfs_root. This allows merging sync requests separately for each tree log. Don't insert root item into the log root tree immediately after log tree is allocated. Root item for log tree is inserted when log tree get synced for the first time. This allows syncing the log root tree without first syncing all log trees. At tree-log sync, btrfs_sync_log first sync the log tree; then updates corresponding root item in the log root tree; sync the log root tree; then update the super block. Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
2008-12-08Btrfs: superblock duplicationYan Zheng
This patch implements superblock duplication. Superblocks are stored at offset 16K, 64M and 256G on every devices. Spaces used by superblocks are preserved by the allocator, which uses a reverse mapping function to find the logical addresses that correspond to superblocks. Thank you, Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
2008-11-12Btrfs: mount ro and remount supportYan Zheng
This patch adds mount ro and remount support. The main changes in patch are: adding btrfs_remount and related helper function; splitting the transaction related code out of close_ctree into btrfs_commit_super; updating allocator to properly handle read only block group. Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
2008-11-06Btrfs: Add ordered async work queuesChris Mason
Btrfs uses kernel threads to create async work queues for cpu intensive operations such as checksumming and decompression. These work well, but they make it difficult to keep IO order intact. A single writepages call from pdflush or fsync will turn into a number of bios, and each bio is checksummed in parallel. Once the checksum is computed, the bio is sent down to the disk, and since we don't control the order in which the parallel operations happen, they might go down to the disk in almost any order. The code deals with this somewhat by having deep work queues for a single kernel thread, making it very likely that a single thread will process all the bios for a single inode. This patch introduces an explicitly ordered work queue. As work structs are placed into the queue they are put onto the tail of a list. They have three callbacks: ->func (cpu intensive processing here) ->ordered_func (order sensitive processing here) ->ordered_free (free the work struct, all processing is done) The work struct has three callbacks. The func callback does the cpu intensive work, and when it completes the work struct is marked as done. Every time a work struct completes, the list is checked to see if the head is marked as done. If so the ordered_func callback is used to do the order sensitive processing and the ordered_free callback is used to do any cleanup. Then we loop back and check the head of the list again. This patch also changes the checksumming code to use the ordered workqueues. One a 4 drive array, it increases streaming writes from 280MB/s to 350MB/s. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-10-29Btrfs: Add zlib compression supportChris Mason
This is a large change for adding compression on reading and writing, both for inline and regular extents. It does some fairly large surgery to the writeback paths. Compression is off by default and enabled by mount -o compress. Even when the -o compress mount option is not used, it is possible to read compressed extents off the disk. If compression for a given set of pages fails to make them smaller, the file is flagged to avoid future compression attempts later. * While finding delalloc extents, the pages are locked before being sent down to the delalloc handler. This allows the delalloc handler to do complex things such as cleaning the pages, marking them writeback and starting IO on their behalf. * Inline extents are inserted at delalloc time now. This allows us to compress the data before inserting the inline extent, and it allows us to insert an inline extent that spans multiple pages. * All of the in-memory extent representations (extent_map.c, ordered-data.c etc) are changed to record both an in-memory size and an on disk size, as well as a flag for compression. From a disk format point of view, the extent pointers in the file are changed to record the on disk size of a given extent and some encoding flags. Space in the disk format is allocated for compression encoding, as well as encryption and a generic 'other' field. Neither the encryption or the 'other' field are currently used. In order to limit the amount of data read for a single random read in the file, the size of a compressed extent is limited to 128k. This is a software only limit, the disk format supports u64 sized compressed extents. In order to limit the ram consumed while processing extents, the uncompressed size of a compressed extent is limited to 256k. This is a software only limit and will be subject to tuning later. Checksumming is still done on compressed extents, and it is done on the uncompressed version of the data. This way additional encodings can be layered on without having to figure out which encoding to checksum. Compression happens at delalloc time, which is basically singled threaded because it is usually done by a single pdflush thread. This makes it tricky to spread the compression load across all the cpus on the box. We'll have to look at parallel pdflush walks of dirty inodes at a later time. Decompression is hooked into readpages and it does spread across CPUs nicely. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25Btrfs: Tree logging fixesChris Mason
* Pin down data blocks to prevent them from being reallocated like so: trans 1: allocate file extent trans 2: free file extent trans 3: free file extent during old snapshot deletion trans 3: allocate file extent to new file trans 3: fsync new file Before the tree logging code, this was legal because the fsync would commit the transation that did the final data extent free and the transaction that allocated the extent to the new file at the same time. With the tree logging code, the tree log subtransaction can commit before the transaction that freed the extent. If we crash, we're left with two different files using the extent. * Don't wait in start_transaction if log replay is going on. This avoids deadlocks from iput while we're cleaning up link counts in the replay code. * Don't deadlock in replay_one_name by trying to read an inode off the disk while holding paths for the directory * Hold the buffer lock while we mark a buffer as written. This closes a race where someone is changing a buffer while we write it. They are supposed to mark it dirty again after they change it, but this violates the cow rules. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25Btrfs: Add a write ahead tree log to optimize synchronous operationsChris Mason
File syncs and directory syncs are optimized by copying their items into a special (copy-on-write) log tree. There is one log tree per subvolume and the btrfs super block points to a tree of log tree roots. After a crash, items are copied out of the log tree and back into the subvolume. See tree-log.c for all the details. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25Btrfs: Wait for async bio submissions to make some progress at queue timeChris Mason
Before, the btrfs bdi congestion function was used to test for too many async bios. This keeps that check to throttle pdflush, but also adds a check while queuing bios. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25Btrfs: Transaction commit: don't use filemap_fdatawaitChris Mason
After writing out all the remaining btree blocks in the transaction, the commit code would use filemap_fdatawait to make sure it was all on disk. This means it would wait for blocks written by other procs as well. The new code walks the list of blocks for this transaction again and waits only for those required by this transaction. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25Btrfs: Online btree defragmentation fixesChris Mason
The btree defragger wasn't making forward progress because the new key wasn't being saved by the btrfs_search_forward function. This also disables the automatic btree defrag, it wasn't scaling well to huge filesystems. The auto-defrag needs to be done differently. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25Add btrfs_end_transaction_throttle to force writers to wait for pending commitsChris Mason
The existing throttle mechanism was often not sufficient to prevent new writers from coming in and making a given transaction run forever. This adds an explicit wait at the end of most operations so they will allow the current transaction to close. There is no wait inside file_write, inode updates, or cow filling, all which have different deadlock possibilities. This is a temporary measure until better asynchronous commit support is added. This code leads to stalls as it waits for data=ordered writeback, and it really needs to be fixed. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25Btrfs: Add mount -o degraded to allow mounts to continue with missing devicesChris Mason
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25Btrfs: Handle write errors on raid1 and raid10Chris Mason
When duplicate copies exist, writes are allowed to fail to one of those copies. This changeset includes a few changes that allow the FS to continue even when some IOs fail. It also adds verification of the parent generation number for btree blocks. This generation is stored in the pointer to a block, and it ensures that missed writes to are detected. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25Btrfs: Pass down the expected generation number when reading tree blocksChris Mason
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25Btrfs: Create a work queue for bio writesChris Mason
This allows checksumming to happen in parallel among many cpus, and keeps us from bogging down pdflush with the checksumming code. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25Btrfs: Write out all super blocks on commit, and bring back proper barrier ↵Chris Mason
support Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25Btrfs: Handle data block end_io through the async work queueChris Mason
Before it was done by the bio end_io routine, the work queue code is able to scale much better with faster IO subsystems. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25Btrfs: Verify checksums on tree blocks found without read_tree_blockChris Mason
Checksums were only verified by btrfs_read_tree_block, which meant the functions to probe the page cache for blocks were not validating checksums. Normally this is fine because the buffers will only be in cache if they have already been validated. But, there is a window while the buffer is being read from disk where it could be up to date in the cache but not yet verified. This patch makes sure all buffers go through checksum verification before they are used. This is safer, and it prevents modification of buffers before they go through the csum code. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25Btrfs: Add support for device scanning and detection ioctlsChris Mason
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25Btrfs: Add support for multiple devices per filesystemChris Mason
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2008-09-25Btrfs: Add some simple throttling to wait for data=ordered and snapshot deletionChris Mason
Signed-off-by: Chris Mason <chris.mason@oracle.com>