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2006-10-11[PATCH] bitmap: parse input from kernel and user buffersReinette Chatre
lib/bitmap.c:bitmap_parse() is a library function that received as input a user buffer. This seemed to have originated from the way the write_proc function of the /proc filesystem operates. This has been reworked to not use kmalloc and eliminates a lot of get_user() overhead by performing one access_ok before using __get_user(). We need to test if we are in kernel or user space (is_user) and access the buffer differently. We cannot use __get_user() to access kernel addresses in all cases, for example in architectures with separate address space for kernel and user. This function will be useful for other uses as well; for example, taking input for /sysfs instead of /proc, so it was changed to accept kernel buffers. We have this use for the Linux UWB project, as part as the upcoming bandwidth allocator code. Only a few routines used this function and they were changed too. Signed-off-by: Reinette Chatre <reinette.chatre@linux.intel.com> Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com> Cc: Paul Jackson <pj@sgi.com> Cc: Joe Korty <joe.korty@ccur.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25[PATCH] kernel-doc for lib/bitmap.cRandy Dunlap
Make corrections/fixes to kernel-doc in lib/bitmap.c and include it in DocBook template. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26[PATCH] bitops: hweight() related cleanupAkinobu Mita
By defining generic hweight*() routines - hweight64() will be defined on all architectures - hweight_long() will use architecture optimized hweight32() or hweight64() I found two possible cleanups by these reasons. Signed-off-by: Akinobu Mita <mita@miraclelinux.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-24[PATCH] bitmap: region restructuringPaul Jackson
Restructure the bitmap_*_region() operations, to avoid code duplication. Also reduces binary text size by about 100 bytes (ia64 arch). The original Bottomley bitmap_*_region patch added about 1000 bytes of compiled kernel text (ia64). The Mundt multiword extension added another 600 bytes, and this restructuring patch gets back about 100 bytes. But the real motivation was the reduced amount of duplicated code. Tested by Paul Mundt using <= BITS_PER_LONG as well as power of 2 aligned multiword spanning allocations. Signed-off-by: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-24[PATCH] bitmap: region multiword spanning supportPaul Mundt
Add support to the lib/bitmap.c bitmap_*_region() routines For bitmap regions larger than one word (nbits > BITS_PER_LONG). This removes a BUG_ON() in lib bitmap. I have an updated store queue API for SH that is currently using this with relative success, and at first glance, it seems like this could be useful for x86 (arch/i386/kernel/pci-dma.c) as well. Particularly for anything using dma_declare_coherent_memory() on large areas and that attempts to allocate large buffers from that space. Paul Jackson also did some cleanup to this patch. Signed-off-by: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-24[PATCH] bitmap: region cleanupPaul Jackson
Paul Mundt <lethal@linux-sh.org> says: This patch set implements a number of patches to clean up and restructure the bitmap region code, in addition to extending the interface to support multiword spanning allocations. The current implementation (before this patch set) is limited by only being able to allocate pages <= BITS_PER_LONG, as noted by the strategically positioned BUG_ON() at lib/bitmap.c:752: /* We don't do regions of pages > BITS_PER_LONG. The * algorithm would be a simple look for multiple zeros in the * array, but there's no driver today that needs this. If you * trip this BUG(), you get to code it... */ BUG_ON(pages > BITS_PER_LONG); As I seem to have been the first person to trigger this, the result ends up being the following patch set with the help of Paul Jackson. The final patch in the series eliminates quite a bit of code duplication, so the bitmap code size ends up being smaller than the current implementation as an added bonus. After these are applied, it should already be possible to do multiword allocations with dma_alloc_coherent() out of ranges established by dma_declare_coherent_memory() on x86 without having to change any of the code, and the SH store queue API will follow up on this as the other user that needs support for this. This patch: Some code cleanup on the lib/bitmap.c bitmap_*_region() routines: * spacing * variable names * comments Has no change to code function. Signed-off-by: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-08[PATCH] cpuset: better bitmap remap defaultsPaul Jackson
Fix the default behaviour for the remap operators in bitmap, cpumask and nodemask. As previously submitted, the pair of masks <A, B> defined a map of the positions of the set bits in A to the corresponding bits in B. This is still true. The issue is how to map the other positions, corresponding to the unset (0) bits in A. As previously submitted, they were all mapped to the first set bit position in B, a constant map. When I tried to code per-vma mempolicy rebinding using these remap operators, I realized this was wrong. This patch changes the default to map all the unset bit positions in A to the same positions in B, the identity map. For example, if A has bits 4-7 set, and B has bits 9-12 set, then the map defined by the pair <A, B> maps each bit position in the first 32 bits as follows: 0 ==> 0 ... 3 ==> 3 4 ==> 9 ... 7 ==> 12 8 ==> 8 9 ==> 9 ... 31 ==> 31 This now corresponds to the typical behaviour desired when migrating pages and policies from one cpuset to another. The pages on nodes within the original cpuset, and the references in memory policies to nodes within the original cpuset, are migrated to the corresponding cpuset-relative nodes in the destination cpuset. Other pages and node references are left untouched. Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30[PATCH] cpusets: bitmap and mask remap operatorsPaul Jackson
In the forthcoming task migration support, a key calculation will be mapping cpu and node numbers from the old set to the new set while preserving cpuset-relative offset. For example, if a task and its pages on nodes 8-11 are being migrated to nodes 24-27, then pages on node 9 (the 2nd node in the old set) should be moved to node 25 (the 2nd node in the new set.) As with other bitmap operations, the proper way to code this is to provide the underlying calculation in lib/bitmap.c, and then to provide the usual cpumask and nodemask wrappers. This patch provides that. These operations are termed 'remap' operations. Both remapping a single bit and a set of bits is supported. Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25[PATCH] Use ALIGN to remove duplicate codeNick Wilson
This patch makes use of ALIGN() to remove duplicate round-up code. Signed-off-by: Nick Wilson <njw@osdl.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!