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2009-06-18md: Move check for bitmap presence to personality code.Andre Noll
If the superblock of a component device indicates the presence of a bitmap but the corresponding raid personality does not support bitmaps (raid0, linear, multipath, faulty), then something is seriously wrong and we'd better refuse to run such an array. Currently, this check is performed while the superblocks are examined, i.e. before entering personality code. Therefore the generic md layer must know which raid levels support bitmaps and which do not. This patch avoids this layer violation without adding identical code to various personalities. This is accomplished by introducing a new public function to md.c, md_check_no_bitmap(), which replaces the hard-coded checks in the superblock loading functions. A call to md_check_no_bitmap() is added to the ->run method of each personality which does not support bitmaps and assembly is aborted if at least one component device contains a bitmap. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-18md: remove chunksize rounding from common code.NeilBrown
It is easiest to round sizes to multiples of chunk size in the personality code for those personalities which care. Those personalities now do the rounding, so we can remove that function from common code. Also remove the upper bound on the size of a chunk, and the lower bound on the size of a device (1 chunk), neither of which really buy us anything. Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-18md: raid0/linear: ensure device sizes are rounded to chunk size.NeilBrown
This is currently ensured by common code, but it is more reliable to ensure it where it is needed in personality code. All the other personalities that care already round the size to the chunk_size. raid0 and linear are the only hold-outs. Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-18md: move assignment of ->utime so that it never gets skipped.NeilBrown
Currently the assignment to utime gets skipped for 'external' metadata. So move it to the top of the function so that it always gets effected. This is of largely cosmetic interest. Nothing actually depends on ->utime being right for external arrays. "mdadm --monitor" does use it for 0.90 and 1.x arrays, but with mdadm-3.0, this is not important for external metadata. Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-18md: Push down reconstruction log message to personality code.Andre Noll
Currently, the md layer checks in analyze_sbs() if the raid level supports reconstruction (mddev->level >= 1) and if reconstruction is in progress (mddev->recovery_cp != MaxSector). Move that printk into the personality code of those raid levels that care (levels 1, 4, 5, 6, 10). Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-18md: merge reconfig and check_reshape methods.NeilBrown
The difference between these two methods is artificial. Both check that a pending reshape is valid, and perform any aspect of it that can be done immediately. 'reconfig' handles chunk size and layout. 'check_reshape' handles raid_disks. So make them just one method. Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-18md: remove unnecessary arguments from ->reconfig method.NeilBrown
Passing the new layout and chunksize as args is not necessary as the mddev has fields for new_check and new_layout. This is preparation for combining the check_reshape and reconfig methods Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-18md: raid5: check stripe cache is large enough in start_reshapeNeilBrown
In reshape cases that do not change the number of devices, start_reshape is called without first calling check_reshape. Currently, the check that the stripe_cache is large enough is only done in check_reshape. It should be in start_reshape too. Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-18md: raid0: chunk_sectors cleanups.NeilBrown
following the conversion to chunk_sectors, there is room for cleaning up a little. Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-18md: fix some comments.Andre Noll
1/ Raid5 has learned to take over also raid4 and raid6 arrays. 2/ new_chunk in mdp_superblock_1 is in sectors, not bytes. Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-18md/raid5: Use is_power_of_2() in raid5_reconfig()/raid6_reconfig().Andre Noll
Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-18md: convert conf->chunk_size and conf->prev_chunk to sectors.Andre Noll
This kills some more shifts. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-18md: Convert mddev->new_chunk to sectors.Andre Noll
A straight-forward conversion which gets rid of some multiplications/divisions/shifts. The patch also introduces a couple of new ones, most of which are due to conf->chunk_size still being represented in bytes. This will be cleaned up in subsequent patches. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-18md: Make mddev->chunk_size sector-based.Andre Noll
This patch renames the chunk_size field to chunk_sectors with the implied change of semantics. Since is_power_of_2(chunk_size) = is_power_of_2(chunk_sectors << 9) = is_power_of_2(chunk_sectors) these bits don't need an adjustment for the shift. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: raid0 :Enables chunk size other than powers of 2.raz ben yehuda
Maintain two flows, one for pow2 chunk sizes (which uses masks and shift), and a flow for the general case (which uses sector_div). This is for the sake of performance. - introduce map_sector and is_io_in_chunk_boundary to encapsulate those two flows better for raid0_make_request - fix blk_mergeable to support the two flows. Signed-off-by: raziebe@gmail.com Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: prepare for non-power-of-two chunk sizesraz ben yehuda
Remove chunk size check from md as this is now performed in the run function in each personality. Replace chunk size power 2 code calculations by a regular division. Signed-off-by: raziebe@gmail.com Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: raid5: chunk size check in setup_confraz ben yehuda
have raid5 check chunk size in run/reshape method instead of in md Signed-off-by: raziebe@gmail.com Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: raid10: chunk size check in runraz ben yehuda
have raid10 check chunk size in run method instead of in md Signed-off-by: raziebe@gmail.com Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: raid0: chunk size check in raid0_runraz ben yehuda
have raid0 check chunk size in run method instead of in md. This is part of a series moving the checks from common code to the personalities where they belong. hardsect is short and chunksize is an int, so it is safe to use %. Signed-off-by: raziebe@gmail.com Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: have raid0 report its formationraz ben yehuda
Report to the user what are the raid zones Signed-off-by: raziebe@gmail.com Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: have raid0 compile with MD_DEBUG onraz ben yehuda
Because of the removal of the device list from the strips raid0 did not compile with MD_DEBUG flag on Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: Binary search in linear raidSandeep K Sinha
Replace the linear search with binary search in which_dev. Signed-off-by: Sandeep K Sinha <sandeepksinha@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: Removing num_sector and replacing start_sector with end_sectorSandeep K Sinha
Remove num_sectors from dev_info and replace start_sector with end_sector. This makes a lot of comparisons much simpler. Signed-off-by: Sandeep K Sinha <sandeepksinha@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: Removal of hash table in linear raidSandeep K Sinha
Get rid of sector_div and hash table for linear raid and replace with a linear search in which_dev. The hash table adds a lot of complexity for little if any gain. Ultimately a binary search will be used which will have smaller cache foot print, a similar number of memory access, and no divisions. Signed-off-by: Sandeep K Sinha <sandeepksinha@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: remove mddev_to_conf "helper" macroNeilBrown
Having a macro just to cast a void* isn't really helpful. I would must rather see that we are simply de-referencing ->private, than have to know what the macro does. So open code the macro everywhere and remove the pointless cast. Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: raid0: remove setting of segment boundary.NeilBrown
This setting doesn't seem to make sense (half the chunk size??) and shouldn't be needed. The segment boundary exported by raid0 should simply be the minimum of the segment boundary of all component devices. And we already get that right. Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: raid0: remove ->dev pointer from strip_zone structureNeilBrown
If we treat conf->devlist more like a 2 dimensional array, we can get the devlist for a particular zone simply by indexing that array, so we don't need to store the pointers to subarrays in strip_zone. This makes strip_zone smaller and so (hopefully) searches faster. Signed-of-by: NeilBrown <neilb@suse.de>
2009-06-16md: raid0: remove ->sectors from the strip_zone structure.NeilBrown
storing ->sectors is redundant as is can be computed from the difference z->zone_end - (z-1)->zone_end The one place where it is used, it is just as efficient to use a zone_end value instead. And removing it makes strip_zone smaller, so they array of these that is searched on every request has a better chance to say in cache. So discard the field and get the value from elsewhere. Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: raid0: Fix a memory leak when stopping a raid0 array.Andre Noll
raid0_stop() removes all references to the raid0 configuration but misses to free the ->devlist buffer. This patch closes this leak, removes a pointless initialization and fixes a coding style issue in raid0_stop(). Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: raid0: Allocate all buffers for the raid0 configuration in one function.Andre Noll
Currently the raid0 configuration is allocated in raid0_run() while the buffers for the strip_zone and the dev_list arrays are allocated in create_strip_zones(). On errors, all three buffers are freed in raid0_run(). It's easier and more readable to do the allocation and cleanup within a single function. So move that code into create_strip_zones(). Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: raid0: Make raid0_run() return a proper error code.Andre Noll
Currently raid0_run() always returns -ENOMEM on errors. This is incorrect as running the array might fail for other reasons, for example because not all component devices were available. This patch changes create_strip_zones() so that it returns a proper error code (either -ENOMEM or -EINVAL) rather than 1 on errors and makes raid0_run(), its single caller, return that value instead of -ENOMEM. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: raid0: Remove hash spacing and sector shift.Andre Noll
The "sector_shift" and "spacing" fields of struct raid0_private_data were only used for the hash table lookups. So the removal of the hash table allows get rid of these fields as well which simplifies create_strip_zones() and raid0_run() quite a bit. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: raid0: Remove hash table.Andre Noll
The raid0 hash table has become unused due to the changes in the previous patch. This patch removes the hash table allocation and setup code and kills the hash_table field of struct raid0_private_data. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md/raid0: two cleanups in create_stripe_zones.NeilBrown
1/ remove current_start. The same value is available in zone->dev_start and storing it separately doesn't gain anything. 2/ rename curr_zone_start to curr_zone_end as we are now more focused on the 'end' of each zone. We end up storing the same number though - the old name was a little confusing (and what does 'current' mean in this context anyway). Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: raid0: Replace hash table lookup by looping over all strip_zones.Andre Noll
The number of strip_zones of a raid0 array is bounded by the number of drives in the array and is in fact much smaller for typical setups. For example, any raid0 array containing identical disks will have only a single strip_zone. Therefore, the hash tables which are used for quickly finding the strip_zone that holds a particular sector are of questionable value and add quite a bit of unnecessary complexity. This patch replaces the hash table lookup by equivalent code which simply loops over all strip zones to find the zone that holds the given sector. In order to make this loop as fast as possible, the zone->start field of struct strip_zone has been renamed to zone_end, and it now stores the beginning of the next zone in sectors. This allows to save one addition in the loop. Subsequent cleanup patches will remove the hash table structure. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-11Merge branch 'for-2.6.31' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds
* 'for-2.6.31' of git://git.kernel.dk/linux-2.6-block: (153 commits) block: add request clone interface (v2) floppy: fix hibernation ramdisk: remove long-deprecated "ramdisk=" boot-time parameter fs/bio.c: add missing __user annotation block: prevent possible io_context->refcount overflow Add serial number support for virtio_blk, V4a block: Add missing bounce_pfn stacking and fix comments Revert "block: Fix bounce limit setting in DM" cciss: decode unit attention in SCSI error handling code cciss: Remove no longer needed sendcmd reject processing code cciss: change SCSI error handling routines to work with interrupts enabled. cciss: separate error processing and command retrying code in sendcmd_withirq_core() cciss: factor out fix target status processing code from sendcmd functions cciss: simplify interface of sendcmd() and sendcmd_withirq() cciss: factor out core of sendcmd_withirq() for use by SCSI error handling code cciss: Use schedule_timeout_uninterruptible in SCSI error handling code block: needs to set the residual length of a bidi request Revert "block: implement blkdev_readpages" block: Fix bounce limit setting in DM Removed reference to non-existing file Documentation/PCI/PCI-DMA-mapping.txt ... Manually fix conflicts with tracing updates in: block/blk-sysfs.c drivers/ide/ide-atapi.c drivers/ide/ide-cd.c drivers/ide/ide-floppy.c drivers/ide/ide-tape.c include/trace/events/block.h kernel/trace/blktrace.c
2009-06-10Merge branch 'tracing-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (244 commits) Revert "x86, bts: reenable ptrace branch trace support" tracing: do not translate event helper macros in print format ftrace/documentation: fix typo in function grapher name tracing/events: convert block trace points to TRACE_EVENT(), fix !CONFIG_BLOCK tracing: add protection around module events unload tracing: add trace_seq_vprint interface tracing: fix the block trace points print size tracing/events: convert block trace points to TRACE_EVENT() ring-buffer: fix ret in rb_add_time_stamp ring-buffer: pass in lockdep class key for reader_lock tracing: add annotation to what type of stack trace is recorded tracing: fix multiple use of __print_flags and __print_symbolic tracing/events: fix output format of user stack tracing/events: fix output format of kernel stack tracing/trace_stack: fix the number of entries in the header ring-buffer: discard timestamps that are at the start of the buffer ring-buffer: try to discard unneeded timestamps ring-buffer: fix bug in ring_buffer_discard_commit ftrace: do not profile functions when disabled tracing: make trace pipe recognize latency format flag ...
2009-06-09tracing/events: convert block trace points to TRACE_EVENT()Li Zefan
TRACE_EVENT is a more generic way to define tracepoints. Doing so adds these new capabilities to this tracepoint: - zero-copy and per-cpu splice() tracing - binary tracing without printf overhead - structured logging records exposed under /debug/tracing/events - trace events embedded in function tracer output and other plugins - user-defined, per tracepoint filter expressions ... Cons: - no dev_t info for the output of plug, unplug_timer and unplug_io events. no dev_t info for getrq and sleeprq events if bio == NULL. no dev_t info for rq_abort,...,rq_requeue events if rq->rq_disk == NULL. This is mainly because we can't get the deivce from a request queue. But this may change in the future. - A packet command is converted to a string in TP_assign, not TP_print. While blktrace do the convertion just before output. Since pc requests should be rather rare, this is not a big issue. - In blktrace, an event can have 2 different print formats, but a TRACE_EVENT has a unique format, which means we have some unused data in a trace entry. The overhead is minimized by using __dynamic_array() instead of __array(). I've benchmarked the ioctl blktrace vs the splice based TRACE_EVENT tracing: dd dd + ioctl blktrace dd + TRACE_EVENT (splice) 1 7.36s, 42.7 MB/s 7.50s, 42.0 MB/s 7.41s, 42.5 MB/s 2 7.43s, 42.3 MB/s 7.48s, 42.1 MB/s 7.43s, 42.4 MB/s 3 7.38s, 42.6 MB/s 7.45s, 42.2 MB/s 7.41s, 42.5 MB/s So the overhead of tracing is very small, and no regression when using those trace events vs blktrace. And the binary output of TRACE_EVENT is much smaller than blktrace: # ls -l -h -rw-r--r-- 1 root root 8.8M 06-09 13:24 sda.blktrace.0 -rw-r--r-- 1 root root 195K 06-09 13:24 sda.blktrace.1 -rw-r--r-- 1 root root 2.7M 06-09 13:25 trace_splice.out Following are some comparisons between TRACE_EVENT and blktrace: plug: kjournald-480 [000] 303.084981: block_plug: [kjournald] kjournald-480 [000] 303.084981: 8,0 P N [kjournald] unplug_io: kblockd/0-118 [000] 300.052973: block_unplug_io: [kblockd/0] 1 kblockd/0-118 [000] 300.052974: 8,0 U N [kblockd/0] 1 remap: kjournald-480 [000] 303.085042: block_remap: 8,0 W 102736992 + 8 <- (8,8) 33384 kjournald-480 [000] 303.085043: 8,0 A W 102736992 + 8 <- (8,8) 33384 bio_backmerge: kjournald-480 [000] 303.085086: block_bio_backmerge: 8,0 W 102737032 + 8 [kjournald] kjournald-480 [000] 303.085086: 8,0 M W 102737032 + 8 [kjournald] getrq: kjournald-480 [000] 303.084974: block_getrq: 8,0 W 102736984 + 8 [kjournald] kjournald-480 [000] 303.084975: 8,0 G W 102736984 + 8 [kjournald] bash-2066 [001] 1072.953770: 8,0 G N [bash] bash-2066 [001] 1072.953773: block_getrq: 0,0 N 0 + 0 [bash] rq_complete: konsole-2065 [001] 300.053184: block_rq_complete: 8,0 W () 103669040 + 16 [0] konsole-2065 [001] 300.053191: 8,0 C W 103669040 + 16 [0] ksoftirqd/1-7 [001] 1072.953811: 8,0 C N (5a 00 08 00 00 00 00 00 24 00) [0] ksoftirqd/1-7 [001] 1072.953813: block_rq_complete: 0,0 N (5a 00 08 00 00 00 00 00 24 00) 0 + 0 [0] rq_insert: kjournald-480 [000] 303.084985: block_rq_insert: 8,0 W 0 () 102736984 + 8 [kjournald] kjournald-480 [000] 303.084986: 8,0 I W 102736984 + 8 [kjournald] Changelog from v2 -> v3: - use the newly introduced __dynamic_array(). Changelog from v1 -> v2: - use __string() instead of __array() to minimize the memory required to store hex dump of rq->cmd(). - support large pc requests. - add missing blk_fill_rwbs_rq() in block_rq_requeue TRACE_EVENT. - some cleanups. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> LKML-Reference: <4A2DF669.5070905@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2009-06-09md/raid5: fix bug in reshape code when chunk_size decreases.NeilBrown
Now that we support changing the chunksize, we calculate "reshape_sectors" to be the max of number of sectors in old and new chunk size. However there is one please where we still use 'chunksize' rather than 'reshape_sectors'. This causes a reshape that reduces the size of chunks to freeze. Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-09md/raid5 - avoid deadlocks in get_active_stripe during reshapeNeilBrown
md has functionality to 'quiesce' and array so that all pending IO completed and no new IO starts. This is used to achieve a stable state before making internal changes. Currently this quiescing applies equally to normal IO, resync IO, and reshape IO. However there is a problem with applying it to reshape IO. Reshape can have multiple 'stripe_heads' that must be active together. If the quiesce come between allocating the first and the last of such a collection, then we deadlock, as the last will not be allocated until the quiesce is lifted, the quiesce will not be lifted until the first (which has been allocated) gets used, and that first cannot be used until the last is allocated. It is not necessary to inhibit reshape IO when a quiesce is requested. Those places in the code that require a full quiesce will ensure the reshape thread is not running at all. So allow reshape requests to get access to new stripe_heads without being blocked by a 'quiesce'. This only affects in-place reshapes (i.e. where the array does not grow or shrink) and these are only newly supported. So this patch is not needed in earlier kernels. Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-09md/raid5: use conf->raid_disks in preference to mddev->raid_diskNeilBrown
mddev->raid_disks can be changed and any time by a request from user-space. It is a suggestion as to what number of raid_disks is desired. conf->raid_disks can only be changed by the raid5 module with suitable locks in place. It is a statement as to the current number of raid_disks. There are two places where the latter should be used, but the former is used. This can lead to a crash when reshaping an array. This patch changes to mddev-> to conf-> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-09Revert "block: Fix bounce limit setting in DM"Jens Axboe
This reverts commit a05c0205ba031c01bba33a21bf0a35920eb64833. DM doesn't need to access the bounce_pfn directly. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-06-03block: Fix bounce limit setting in DMMartin K. Petersen
blk_queue_bounce_limit() is more than a wrapper about the request queue limits.bounce_pfn variable. Introduce blk_queue_bounce_pfn() which can be called by stacking drivers that wish to set the bounce limit explicitly. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-27md: raid5: change incorrect usage of 'min' macro to 'min_t'NeilBrown
A recent patch to raid5.c use min on an int and a sector_t. This isn't allowed. So change it to min_t(sector_t,x,y). Signed-off-by: NeilBrown <neilb@suse.de>
2009-05-26md: don't use locked_ioctl.NeilBrown
md has no need for the BKL - it does its own locking. So md_ioctl doesn't need to be a locked_ioctl. Signed-off-by: NeilBrown <neilb@suse.de>
2009-05-26md: don't update curr_resync_completed without also updating reshape_position.NeilBrown
In order for the metadata to always be consistent, we mustn't updated curr_resync_completed without also updating reshape_position. The reshape code updates both at the same time. However since commit 97e4f42d62badb0f9fbc27c013e89bc1336a03bc the common md_do_sync will sometimes update curr_resync_completed but is not in a position to update reshape_position. So if MD_RECOVERY_RESHAPE is set (indicating that a reshape is happening, so reshape_position might change), don't update curr_resync_completed in md_do_sync, leave it to the per-personality reshape code. Signed-off-by: NeilBrown <neilb@suse.de>
2009-05-26md: raid5: avoid sector values going negative when testing reshape progress.NeilBrown
As sector_t in unsigned, we cannot afford to let 'safepos' etc go negative. So replace a -= b; by a -= min(b,a); Signed-off-by: NeilBrown <neilb@suse.de>
2009-05-26md: export 'frozen' resync state through sysfsNeilBrown
The md resync engine has a 'frozen' state which ensures that no resync/recovery. This is used to avoid races. Export this state through the 'sync_action' sysfs attribute so that user-space can benefit and also avoid some races. Signed-off-by: NeilBrown <neilb@suse.de>
2009-05-26md: bitmap: improve bitmap maintenance code.NeilBrown
The code for checking which bits in the bitmap can be cleared has 2 problems: 1/ it repeatedly takes and drops a spinlock, where it would make more sense to just hold on to it most of the time. 2/ it doesn't make use of some opportunities to skip large sections of the bitmap This patch fixes those. It will only affect CPU consumption, not correctness. Signed-off-by: NeilBrown <neilb@suse.de>
2009-05-26md: improve errno return when setting array_sizeNeilBrown
Instead of always returns EINVAL if anything goes wrong when setting the array size, add the option of E2BIG if the size requested is too large. This makes it easier for user-space to be sure what went wrong. Signed-off-by: NeilBrown <neilb@suse.de>