user/sven/linux.git/include/linux/idr.h, branch v3.10.44

Merge branch 'for-3.10/drivers' of git://git.kernel.dk/linux-block

2013-05-08T18:51:05Z

Pull block driver updates from Jens Axboe: "It might look big in volume, but when categorized, not a lot of drivers are touched. The pull request contains: - mtip32xx fixes from Micron. - A slew of drbd updates, this time in a nicer series. - bcache, a flash/ssd caching framework from Kent. - Fixes for cciss" * 'for-3.10/drivers' of git://git.kernel.dk/linux-block: (66 commits) bcache: Use bd_link_disk_holder() bcache: Allocator cleanup/fixes cciss: bug fix to prevent cciss from loading in kdump crash kernel cciss: add cciss_allow_hpsa module parameter drivers/block/mg_disk.c: add CONFIG_PM_SLEEP to suspend/resume functions mtip32xx: Workaround for unaligned writes bcache: Make sure blocksize isn't smaller than device blocksize bcache: Fix merge_bvec_fn usage for when it modifies the bvm bcache: Correctly check against BIO_MAX_PAGES bcache: Hack around stuff that clones up to bi_max_vecs bcache: Set ra_pages based on backing device's ra_pages bcache: Take data offset from the bdev superblock. mtip32xx: mtip32xx: Disable TRIM support mtip32xx: fix a smatch warning bcache: Disable broken btree fuzz tester bcache: Fix a format string overflow bcache: Fix a minor memory leak on device teardown bcache: Documentation updates bcache: Use WARN_ONCE() instead of __WARN() bcache: Add missing #include ...

idr: introduce idr_alloc_cyclic()

2013-04-30T01:28:41Z

As Tejun points out, there are several users of the IDR facility that attempt to use it in a cyclic fashion. These users are likely to see -ENOSPC errors after the counter wraps one or more times however. This patchset adds a new idr_alloc_cyclic routine and converts several of these users to it. Many of these users are in obscure parts of the kernel, and I don't have a good way to test some of them. The change is pretty straightforward though, so hopefully it won't be an issue. There is one other cyclic user of idr_alloc that I didn't touch in ipc/util.c. That one is doing some strange stuff that I didn't quite understand, but it looks like it should probably be converted later somehow. This patch: Thus spake Tejun Heo: Ooh, BTW, the cyclic allocation is broken. It's prone to -ENOSPC after the first wraparound. There are several cyclic users in the kernel and I think it probably would be best to implement cyclic support in idr. This patch does that by adding new idr_alloc_cyclic function that such users in the kernel can use. With this, there's no need for a caller to keep track of the last value used as that's now tracked internally. This should prevent the ENOSPC problems that can hit when the "last allocated" counter exceeds INT_MAX. Later patches will convert existing cyclic users to the new interface. Signed-off-by: Jeff Layton Reviewed-by: Tejun Heo Cc: "David S. Miller" Cc: "J. Bruce Fields" Cc: Eric Paris Cc: Jack Morgenstein Cc: John McCutchan Cc: Neil Horman Cc: Or Gerlitz Cc: Robert Love Cc: Roland Dreier Cc: Sridhar Samudrala Cc: Steve Wise Cc: Tom Tucker Cc: Vlad Yasevich Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

idr: document exit conditions on idr_for_each_entry better

2013-03-28T16:10:24Z

And some manual common subexpression elimination which may help the compiler produce smaller code. Signed-off-by: George Spelvin Signed-off-by: Philipp Reisner Signed-off-by: Jens Axboe

idr: deprecate idr_pre_get() and idr_get_new[_above]()

2013-03-13T22:21:47Z

Now that all in-kernel users are converted to ues the new alloc interface, mark the old interface deprecated. We should be able to remove these in a few releases. Signed-off-by: Tejun Heo Cc: Rusty Russell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

idr: fix new kernel-doc warnings

2013-03-13T03:42:09Z

Fix new kernel-doc warnings in idr: Warning(include/linux/idr.h:113): No description found for parameter 'idr' Warning(include/linux/idr.h:113): Excess function parameter 'idp' description in 'idr_find' Warning(lib/idr.c:232): Excess function parameter 'id' description in 'sub_alloc' Warning(lib/idr.c:232): Excess function parameter 'id' description in 'sub_alloc' Signed-off-by: Randy Dunlap Acked-by: Tejun Heo Signed-off-by: Linus Torvalds

idr: implement lookup hint

2013-02-28T03:10:21Z

While idr lookup isn't a particularly heavy operation, it still is too substantial to use in hot paths without worrying about the performance implications. With recent changes, each idr_layer covers 256 slots which should be enough to cover most use cases with single idr_layer making lookup hint very attractive. This patch adds idr->hint which points to the idr_layer which allocated an ID most recently and the fast path lookup becomes if (look up target's prefix matches that of the hinted layer) return hint->ary[ID's offset in the leaf layer]; which can be inlined. idr->hint is set to the leaf node on idr_fill_slot() and cleared from free_layer(). [andriy.shevchenko@linux.intel.com: always do slow path when hint is uninitialized] Signed-off-by: Tejun Heo Cc: Kirill A. Shutemov Cc: Sasha Levin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

idr: add idr_layer->prefix

2013-02-28T03:10:20Z

Add a field which carries the prefix of ID the idr_layer covers. This will be used to implement lookup hint. This patch doesn't make use of the new field and doesn't introduce any behavior difference. Signed-off-by: Tejun Heo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

idr: make idr_layer larger

2013-02-28T03:10:20Z

With recent preloading changes, idr no longer keeps full layer cache per each idr instance (used to be ~6.5k per idr on 64bit) and the previous patch removed restriction on the bitmap size. Both now allow us to have larger layers. Increase IDR_BITS to 8 regardless of BITS_PER_LONG. Each layer is slightly larger than 2k on 64bit and 1k on 32bit and carries 256 entries. The size isn't too large, especially compared to what we used to waste on per-idr caches, and 256 entries should be able to serve most use cases with single layer. The max tree depth is 4 which is much better than the previous 6 on 64bit and 7 on 32bit. Signed-off-by: Tejun Heo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

idr: remove length restriction from idr_layer->bitmap

2013-02-28T03:10:20Z

Currently, idr->bitmap is declared as an unsigned long which restricts the number of bits an idr_layer can contain. All bitops can handle arbitrary positive integer bit number and there's no reason for this restriction. Declare idr_layer->bitmap using DECLARE_BITMAP() instead of a single unsigned long. * idr_layer->bitmap is now an array. '&' dropped from params to bitops. * Replaced "== IDR_FULL" tests with bitmap_full() and removed IDR_FULL. * Replaced find_next_bit() on ~bitmap with find_next_zero_bit(). * Replaced "bitmap = 0" with bitmap_clear(). This patch doesn't (or at least shouldn't) introduce any behavior changes. [akpm@linux-foundation.org: checkpatch fixes] Signed-off-by: Tejun Heo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

idr: remove MAX_IDR_MASK and move left MAX_IDR_* into idr.c

2013-02-28T03:10:20Z

MAX_IDR_MASK is another weirdness in the idr interface. As idr covers whole positive integer range, it's defined as 0x7fffffff or INT_MAX. Its usage in idr_find(), idr_replace() and idr_remove() is bizarre. They basically mask off the sign bit and operate on the rest, so if the caller, by accident, passes in a negative number, the sign bit will be masked off and the remaining part will be used as if that was the input, which is worse than crashing. The constant is visible in idr.h and there are several users in the kernel. * drivers/i2c/i2c-core.c:i2c_add_numbered_adapter() Basically used to test if adap->nr is a negative number which isn't -1 and returns -EINVAL if so. idr_alloc() already has negative @start checking (w/ WARN_ON_ONCE), so this can go away. * drivers/infiniband/core/cm.c:cm_alloc_id() drivers/infiniband/hw/mlx4/cm.c:id_map_alloc() Used to wrap cyclic @start. Can be replaced with max(next, 0). Note that this type of cyclic allocation using idr is buggy. These are prone to spurious -ENOSPC failure after the first wraparound. * fs/super.c:get_anon_bdev() The ID allocated from ida is masked off before being tested whether it's inside valid range. ida allocated ID can never be a negative number and the masking is unnecessary. Update idr_*() functions to fail with -EINVAL when negative @id is specified and update other MAX_IDR_MASK users as described above. This leaves MAX_IDR_MASK without any user, remove it and relocate other MAX_IDR_* constants to lib/idr.c. Signed-off-by: Tejun Heo Cc: Jean Delvare Cc: Roland Dreier Cc: Sean Hefty Cc: Hal Rosenstock Cc: "Marciniszyn, Mike" Cc: Jack Morgenstein Cc: Or Gerlitz Cc: Al Viro Acked-by: Wolfram Sang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds