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* MFC r289618, r290316:ian2016-01-241-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | Fix printf format to allow for bus_size_t not being u_long on all platforms. Fix an alignment check that is wrong in half the busdma implementations. This will enable the elimination of a workaround in the USB driver that artifically allocates buffers twice as big as they need to be (which actually saves memory for very small buffers on the buggy platforms). When deciding how to allocate a dma buffer, armv4, armv6, mips, and x86/iommu all correctly check for the tag alignment <= maxsize as enabling simple uma/malloc based allocation. Powerpc, sparc64, x86/bounce, and arm64/bounce were all checking for alignment < maxsize; on those platforms when alignment was equal to the max size it would fall back to page-based allocators even for very small buffers. This change makes all platforms use the <= check. It should be noted that on all platforms other than arm[v6] and mips, this check is relying on undocumented behavior in malloc(9) that if you allocate a block of a given size it will be aligned to the next larger power-of-2 boundary. There is nothing in the malloc(9) man page that makes that explicit promise (but the busdma code has been relying on this behavior all along so I guess it works). Arm and mips code uses the allocator in kern/subr_busdma_buffalloc.c, which does explicitly implement this promise about size and alignment. Other platforms probably should switch to the aligned allocator.
* MFC r280957rstone2015-09-171-3/+3
| | | | | | | | | | | Fix integer truncation bug in malloc(9) A couple of internal functions used by malloc(9) and uma truncated a size_t down to an int. This could cause any number of issues (e.g. indefinite sleeps, memory corruption) if any kernel subsystem tried to allocate 2GB or more through malloc. zfs would attempt such an allocation when run on a system with 2TB or more of RAM.
* Replace kernel virtual address space allocation with vmem. This providesjeff2013-08-071-3/+3
| | | | | | | | | | | | | transparent layering and better fragmentation. - Normalize functions that allocate memory to use kmem_* - Those that allocate address space are named kva_* - Those that operate on maps are named kmap_* - Implement recursive allocation handling for kmem_arena in vmem. Reviewed by: alc Tested by: pho Sponsored by: EMC / Isilon Storage Division
* Create an architecture-agnostic buffer pool manager that uses uma(9) tocognet2012-12-201-0/+174
manage a set of power-of-2 sized buffers for bus_dmamem_alloc(). This allows the caller to provide the back-end allocator uma allocator, allowing full control of the memory pages backing the pool. For convenience, it provides an optional builtin allocator that provides pages allocated with the VM_MEMATTR_UNCACHEABLE attribute, for managing pools of DMA buffers for BUS_DMA_COHERENT or BUS_DMA_NOCACHE. This also allows the caller to specify a minimum alignment, and it ensures that all buffers start on a boundary and have a length that's a multiple of that value, to avoid using buffers that trigger partial cache line flushes. Submitted by: Ian Lepore <freebsd@damnhippie.dyndns.org>
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