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2019-12-04lib/genalloc.c: rename addr_in_gen_pool to gen_pool_has_addrHuang Shijie
Follow the kernel conventions, rename addr_in_gen_pool to gen_pool_has_addr. [sjhuang@iluvatar.ai: fix Documentation/ too] Link: http://lkml.kernel.org/r/20181229015914.5573-1-sjhuang@iluvatar.ai Link: http://lkml.kernel.org/r/20181228083950.20398-1-sjhuang@iluvatar.ai Signed-off-by: Huang Shijie <sjhuang@iluvatar.ai> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-12Merge tag 'dma-mapping-5.3' of git://git.infradead.org/users/hch/dma-mappingLinus Torvalds
Pull dma-mapping updates from Christoph Hellwig: - move the USB special case that bounced DMA through a device bar into the USB code instead of handling it in the common DMA code (Laurentiu Tudor and Fredrik Noring) - don't dip into the global CMA pool for single page allocations (Nicolin Chen) - fix a crash when allocating memory for the atomic pool failed during boot (Florian Fainelli) - move support for MIPS-style uncached segments to the common code and use that for MIPS and nios2 (me) - make support for DMA_ATTR_NON_CONSISTENT and DMA_ATTR_NO_KERNEL_MAPPING generic (me) - convert nds32 to the generic remapping allocator (me) * tag 'dma-mapping-5.3' of git://git.infradead.org/users/hch/dma-mapping: (29 commits) dma-mapping: mark dma_alloc_need_uncached as __always_inline MIPS: only select ARCH_HAS_UNCACHED_SEGMENT for non-coherent platforms usb: host: Fix excessive alignment restriction for local memory allocations lib/genalloc.c: Add algorithm, align and zeroed family of DMA allocators nios2: use the generic uncached segment support in dma-direct nds32: use the generic remapping allocator for coherent DMA allocations arc: use the generic remapping allocator for coherent DMA allocations dma-direct: handle DMA_ATTR_NO_KERNEL_MAPPING in common code dma-direct: handle DMA_ATTR_NON_CONSISTENT in common code dma-mapping: add a dma_alloc_need_uncached helper openrisc: remove the partial DMA_ATTR_NON_CONSISTENT support arc: remove the partial DMA_ATTR_NON_CONSISTENT support arm-nommu: remove the partial DMA_ATTR_NON_CONSISTENT support ARM: dma-mapping: allow larger DMA mask than supported dma-mapping: truncate dma masks to what dma_addr_t can hold iommu/dma: Apply dma_{alloc,free}_contiguous functions dma-remap: Avoid de-referencing NULL atomic_pool MIPS: use the generic uncached segment support in dma-direct dma-direct: provide generic support for uncached kernel segments au1100fb: fix DMA API abuse ...
2019-06-28lib/genalloc.c: Add algorithm, align and zeroed family of DMA allocatorsFredrik Noring
Provide the algorithm option to DMA allocators as well, along with convenience variants for zeroed and aligned memory. The following four functions are added: - gen_pool_dma_alloc_algo() - gen_pool_dma_alloc_align() - gen_pool_dma_zalloc_algo() - gen_pool_dma_zalloc_align() Signed-off-by: Fredrik Noring <noring@nocrew.org> Tested-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230Thomas Gleixner
Based on 2 normalized pattern(s): this source code is licensed under the gnu general public license version 2 see the file copying for more details this source code is licensed under general public license version 2 see extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 52 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.449021192@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-13lib/genalloc: introduce chunk ownersDan Williams
The p2pdma facility enables a provider to publish a pool of dma addresses for a consumer to allocate. A genpool is used internally by p2pdma to collect dma resources, 'chunks', to be handed out to consumers. Whenever a consumer allocates a resource it needs to pin the 'struct dev_pagemap' instance that backs the chunk selected by pci_alloc_p2pmem(). Currently that reference is taken globally on the entire provider device. That sets up a lifetime mismatch whereby the p2pdma core needs to maintain hacks to make sure the percpu_ref is not released twice. This lifetime mismatch also stands in the way of a fix to devm_memremap_pages() whereby devm_memremap_pages_release() must wait for the percpu_ref ->release() callback to complete before it can proceed to teardown pages. So, towards fixing this situation, introduce the ability to store a 'chunk owner' at gen_pool_add() time, and a facility to retrieve the owner at gen_pool_{alloc,free}() time. For p2pdma this will be used to store and recall individual dev_pagemap reference counter instances per-chunk. Link: http://lkml.kernel.org/r/155727338118.292046.13407378933221579644.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: "Jérôme Glisse" <jglisse@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-03lib/genalloc: add gen_pool_dma_zalloc() for zeroed DMA allocationsFredrik Noring
gen_pool_dma_zalloc() is a zeroed memory variant of gen_pool_dma_alloc(). Also document the return values of both, and indicate NULL as a "%NULL" constant. Signed-off-by: Fredrik Noring <noring@nocrew.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-01-04lib/genalloc.c: fix allocation of aligned buffer from non-aligned chunkAlexey Skidanov
gen_pool_alloc_algo() uses different allocation functions implementing different allocation algorithms. With gen_pool_first_fit_align() allocation function, the returned address should be aligned on the requested boundary. If chunk start address isn't aligned on the requested boundary, the returned address isn't aligned too. The only way to get properly aligned address is to initialize the pool with chunks aligned on the requested boundary. If want to have an ability to allocate buffers aligned on different boundaries (for example, 4K, 1MB, ...), the chunk start address should be aligned on the max possible alignment. This happens because gen_pool_first_fit_align() looks for properly aligned memory block without taking into account the chunk start address alignment. To fix this, we provide chunk start address to gen_pool_first_fit_align() and change its implementation such that it starts looking for properly aligned block with appropriate offset (exactly as is done in CMA). Link: https://lkml.kernel.org/lkml/a170cf65-6884-3592-1de9-4c235888cc8a@intel.com Link: http://lkml.kernel.org/r/1541690953-4623-1-git-send-email-alexey.skidanov@intel.com Signed-off-by: Alexey Skidanov <alexey.skidanov@intel.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Logan Gunthorpe <logang@deltatee.com> Cc: Daniel Mentz <danielmentz@google.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Laura Abbott <labbott@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17lib/genalloc.c: make the avail variable an atomic_long_tStephen Bates
If the amount of resources allocated to a gen_pool exceeds 2^32 then the avail atomic overflows and this causes problems when clients try and borrow resources from the pool. This is only expected to be an issue on 64 bit systems. Add the <linux/atomic.h> header to pull in atomic_long* operations. So that 32 bit systems continue to use atomic32_t but 64 bit systems can use atomic64_t. Link: http://lkml.kernel.org/r/1509033843-25667-1-git-send-email-sbates@raithlin.com Signed-off-by: Stephen Bates <sbates@raithlin.com> Reviewed-by: Logan Gunthorpe <logang@deltatee.com> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Reviewed-by: Daniel Mentz <danielmentz@google.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-31genalloc: Fix an incorrect kerneldoc commentJonathan Corbet
The kerneldoc comment for the genpool_algo_t typedef was incomplete and incorrectly formatted, leading to a raft of warnings during the docs build. Fix it appropriately. Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-12-22genalloc:support allocating specific regionZhao Qiang
Add new algo for genalloc, it reserve a specific region of memory Signed-off-by: Zhao Qiang <qiang.zhao@freescale.com> Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-12-22genalloc:support memory-allocation with bytes-alignment to genallocZhao Qiang
Bytes alignment is required to manage some special RAM, so add gen_pool_first_fit_align to genalloc, meanwhile add gen_pool_alloc_algo to pass algo in case user layer using more than one algo, and pass data to gen_pool_first_fit_align(modify gen_pool_alloc as a wrapper) Signed-off-by: Zhao Qiang <qiang.zhao@freescale.com> Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-09-04genalloc: add support of multiple gen_pools per deviceVladimir Zapolskiy
This change fills devm_gen_pool_create()/gen_pool_get() "name" argument stub with contents and extends of_gen_pool_get() functionality on this basis. If there is no associated platform device with a device node passed to of_gen_pool_get(), the function attempts to get a label property or device node name (= repeats MTD OF partition standard) and seeks for a named gen_pool registered by device of the parent device node. The main idea of the change is to allow registration of independent gen_pools under the same umbrella device, say "partitions" on "storage device", the original functionality of one "partition" per "storage device" is untouched. [akpm@linux-foundation.org: fix constness in devres_find()] [dan.carpenter@oracle.com: freeing const data pointers] Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> Cc: Philipp Zabel <p.zabel@pengutronix.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com> Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <kernel@pengutronix.de> Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04genalloc: add name arg to gen_pool_get() and devm_gen_pool_create()Vladimir Zapolskiy
This change modifies gen_pool_get() and devm_gen_pool_create() client interfaces adding one more argument "name" of a gen_pool object. Due to implementation gen_pool_get() is capable to retrieve only one gen_pool associated with a device even if multiple gen_pools are created, fortunately right at the moment it is sufficient for the clients, hence provide NULL as a valid argument on both producer devm_gen_pool_create() and consumer gen_pool_get() sides. Because only one created gen_pool per device is addressable, explicitly add a restriction to devm_gen_pool_create() to create only one gen_pool per device, this implies two possible error codes returned by the function, account it on client side (only misc/sram). This completes client side changes related to genalloc updates. [akpm@linux-foundation.org: gen_pool_get() cleanup] Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> Cc: Philipp Zabel <p.zabel@pengutronix.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com> Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Cc: Shawn Guo <shawnguo@kernel.org> Cc: Sascha Hauer <kernel@pengutronix.de> Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30genalloc: rename of_get_named_gen_pool() to of_gen_pool_get()Vladimir Zapolskiy
To be consistent with other kernel interface namings, rename of_get_named_gen_pool() to of_gen_pool_get(). In the original function name "_named" suffix references to a device tree property, which contains a phandle to a device and the corresponding device driver is assumed to register a gen_pool object. Due to a weak relation and to avoid any confusion (e.g. in future possible scenario if gen_pool objects are named) the suffix is removed. [sfr@canb.auug.org.au: crypto/marvell/cesa - fix up for of_get_named_gen_pool() rename] Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Philipp Zabel <p.zabel@pengutronix.de> Cc: Shawn Guo <shawn.guo@linaro.org> Cc: Sascha Hauer <kernel@pengutronix.de> Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Jaroslav Kysela <perex@perex.cz> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Boris BREZILLON <boris.brezillon@free-electrons.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30genalloc: rename dev_get_gen_pool() to gen_pool_get()Vladimir Zapolskiy
To be consistent with other genalloc interface namings, rename dev_get_gen_pool() to gen_pool_get(). The original omitted "dev_" prefix is removed, since it points to argument type of the function, and so it does not bring any useful information. [akpm@linux-foundation.org: update arch/arm/mach-socfpga/pm.c] Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Philipp Zabel <p.zabel@pengutronix.de> Cc: Shawn Guo <shawn.guo@linaro.org> Cc: Sascha Hauer <kernel@pengutronix.de> Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Mark Brown <broonie@kernel.org> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Alan Tull <atull@opensource.altera.com> Cc: Dinh Nguyen <dinguyen@opensource.altera.com> Cc: Kevin Hilman <khilman@linaro.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-09lib/genalloc.c: add genpool range check functionLaura Abbott
After allocating an address from a particular genpool, there is no good way to verify if that address actually belongs to a genpool. Introduce addr_in_gen_pool which will return if an address plus size falls completely within the genpool range. Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Acked-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Olof Johansson <olof@lixom.net> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Riley <davidriley@chromium.org> Cc: Ritesh Harjain <ritesh.harjani@gmail.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-10-09lib/genalloc.c: add power aligned algorithmLaura Abbott
One of the more common algorithms used for allocation is to align the start address of the allocation to the order of size requested. Add this as an algorithm option for genalloc. Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Olof Johansson <olof@lixom.net> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: David Riley <davidriley@chromium.org> Cc: Ritesh Harjain <ritesh.harjani@gmail.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23include/linux/genalloc.h: spinlock_t needs spinlock_types.hShawn Guo
Compiling a C file which includes genalloc.h but without spinlock_types.h being included before, we will see the compile error below. include/linux/genalloc.h:54:2: error: unknown type name `spinlock_t' Include spinlock_types.h from genalloc.h to fix the problem. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13lib/genalloc: add a helper function for DMA buffer allocationNicolin Chen
When using pool space for DMA buffer, there might be duplicated calling of gen_pool_alloc() and gen_pool_virt_to_phys() in each implementation. Thus it's better to add a simple helper function, a compatible one to the common dma_alloc_coherent(), to save some code. Signed-off-by: Nicolin Chen <b42378@freescale.com> Cc: "Hans J. Koch" <hjk@hansjkoch.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Eric Miao <eric.y.miao@gmail.com> Cc: Grant Likely <grant.likely@linaro.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Haojian Zhuang <haojian.zhuang@gmail.com> Cc: Jaroslav Kysela <perex@perex.cz> Cc: Kevin Hilman <khilman@deeprootsystems.com> Cc: Liam Girdwood <lgirdwood@gmail.com> Cc: Mark Brown <broonie@kernel.org> Cc: Mauro Carvalho Chehab <m.chehab@samsung.com> Cc: Rob Herring <rob.herring@calxeda.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Sekhar Nori <nsekhar@ti.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11lib/genalloc.c: fix overflow of ending address of memory chunkJoonyoung Shim
In struct gen_pool_chunk, end_addr means the end address of memory chunk (inclusive), but in the implementation it is treated as address + size of memory chunk (exclusive), so it points to the address plus one instead of correct ending address. The ending address of memory chunk plus one will cause overflow on the memory chunk including the last address of memory map, e.g. when starting address is 0xFFF00000 and size is 0x100000 on 32bit machine, ending address will be 0x100000000. Use correct ending address like starting address + size - 1. [akpm@linux-foundation.org: add comment to struct gen_pool_chunk:end_addr] Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29genalloc: add devres support, allow to find a managed pool by devicePhilipp Zabel
This patch adds three exported functions to lib/genalloc.c: devm_gen_pool_create, dev_get_gen_pool, and of_get_named_gen_pool. devm_gen_pool_create is a managed version of gen_pool_create that keeps track of the pool via devres and allows the management code to automatically destroy it after device removal. dev_get_gen_pool retrieves the gen_pool for a given device, if it was created with devm_gen_pool_create, using devres_find. of_get_named_gen_pool retrieves the gen_pool for a given device node and property name, where the property must contain a phandle pointing to a platform device node. The corresponding platform device is then fed into dev_get_gen_pool and the resulting gen_pool is returned. [akpm@linux-foundation.org: make the of_get_named_gen_pool() stub static, fixing a zillion link errors] [akpm@linux-foundation.org: squish "struct device declared inside parameter list" warning] Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de> Acked-by: Grant Likely <grant.likely@secretlab.ca> Tested-by: Michal Simek <monstr@monstr.eu> Cc: Fabio Estevam <fabio.estevam@freescale.com> Cc: Matt Porter <mporter@ti.com> Cc: Dong Aisheng <dong.aisheng@linaro.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Rob Herring <rob.herring@calxeda.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Javier Martin <javier.martin@vista-silicon.com> Cc: Huang Shijie <shijie8@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-06genalloc: make it possible to use a custom allocation algorithmBenjamin Gaignard
Premit use of another algorithm than the default first-fit one. For example a custom algorithm could be used to manage alignment requirements. As I can't predict all the possible requirements/needs for all allocation uses cases, I add a "free" field 'void *data' to pass any needed information to the allocation function. For example 'data' could be used to handle a structure where you store the alignment, the expected memory bank, the requester device, or any information that could influence the allocation algorithm. An usage example may look like this: struct my_pool_constraints { int align; int bank; ... }; unsigned long my_custom_algo(unsigned long *map, unsigned long size, unsigned long start, unsigned int nr, void *data) { struct my_pool_constraints *constraints = data; ... deal with allocation contraints ... return the index in bitmap where perform the allocation } void create_my_pool() { struct my_pool_constraints c; struct gen_pool *pool = gen_pool_create(...); gen_pool_add(pool, ...); gen_pool_set_algo(pool, my_custom_algo, &c); } Add of best-fit algorithm function: most of the time best-fit is slower then first-fit but memory fragmentation is lower. The random buffer allocation/free tests don't show any arithmetic relation between the allocation time and fragmentation but the best-fit algorithm is sometime able to perform the allocation when the first-fit can't. This new algorithm help to remove static allocations on ESRAM, a small but fast on-chip RAM of few KB, used for high-performance uses cases like DMA linked lists, graphic accelerators, encoders/decoders. On the Ux500 (in the ARM tree) we have define 5 ESRAM banks of 128 KB each and use of static allocations becomes unmaintainable: cd arch/arm/mach-ux500 && grep -r ESRAM . ./include/mach/db8500-regs.h:/* Base address and bank offsets for ESRAM */ ./include/mach/db8500-regs.h:#define U8500_ESRAM_BASE 0x40000000 ./include/mach/db8500-regs.h:#define U8500_ESRAM_BANK_SIZE 0x00020000 ./include/mach/db8500-regs.h:#define U8500_ESRAM_BANK0 U8500_ESRAM_BASE ./include/mach/db8500-regs.h:#define U8500_ESRAM_BANK1 (U8500_ESRAM_BASE + U8500_ESRAM_BANK_SIZE) ./include/mach/db8500-regs.h:#define U8500_ESRAM_BANK2 (U8500_ESRAM_BANK1 + U8500_ESRAM_BANK_SIZE) ./include/mach/db8500-regs.h:#define U8500_ESRAM_BANK3 (U8500_ESRAM_BANK2 + U8500_ESRAM_BANK_SIZE) ./include/mach/db8500-regs.h:#define U8500_ESRAM_BANK4 (U8500_ESRAM_BANK3 + U8500_ESRAM_BANK_SIZE) ./include/mach/db8500-regs.h:#define U8500_ESRAM_DMA_LCPA_OFFSET 0x10000 ./include/mach/db8500-regs.h:#define U8500_DMA_LCPA_BASE (U8500_ESRAM_BANK0 + U8500_ESRAM_DMA_LCPA_OFFSET) ./include/mach/db8500-regs.h:#define U8500_DMA_LCLA_BASE U8500_ESRAM_BANK4 I want to use genalloc to do dynamic allocations but I need to be able to fine tune the allocation algorithm. I my case best-fit algorithm give better results than first-fit, but it will not be true for every use case. Signed-off-by: Benjamin Gaignard <benjamin.gaignard@stericsson.com> Cc: Huang Ying <ying.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-08-03lib, Make gen_pool memory allocator locklessHuang Ying
This version of the gen_pool memory allocator supports lockless operation. This makes it safe to use in NMI handlers and other special unblockable contexts that could otherwise deadlock on locks. This is implemented by using atomic operations and retries on any conflicts. The disadvantage is that there may be livelocks in extreme cases. For better scalability, one gen_pool allocator can be used for each CPU. The lockless operation only works if there is enough memory available. If new memory is added to the pool a lock has to be still taken. So any user relying on locklessness has to ensure that sufficient memory is preallocated. The basic atomic operation of this allocator is cmpxchg on long. On architectures that don't have NMI-safe cmpxchg implementation, the allocator can NOT be used in NMI handler. So code uses the allocator in NMI handler should depend on CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG. Signed-off-by: Huang Ying <ying.huang@intel.com> Reviewed-by: Andi Kleen <ak@linux.intel.com> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>
2011-05-25lib/genalloc.c: add support for specifying the physical addressJean-Christophe PLAGNIOL-VILLARD
So we can specify the virtual address as the base of the pool chunk and then get physical addresses for hardware IP. For example on at91 we will use this on spi, uart or macb Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Patrice VILCHEZ <patrice.vilchez@atmel.com> Cc: Jes Sorensen <jes@wildopensource.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-25include/linux/genalloc.h: add multiple-inclusion guardsJean-Christophe PLAGNIOL-VILLARD
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Patrice VILCHEZ <patrice.vilchez@atmel.com> Cc: Jes Sorensen <jes@wildopensource.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-10-02[PATCH] LIB: add gen_pool_destroy()Steve Wise
Modules using the genpool allocator need to be able to destroy the data structure when unloading. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Cc: Dean Nelson <dcn@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23[PATCH] change gen_pool allocator to not touch managed memoryDean Nelson
Modify the gen_pool allocator (lib/genalloc.c) to utilize a bitmap scheme instead of the buddy scheme. The purpose of this change is to eliminate the touching of the actual memory being allocated. Since the change modifies the interface, a change to the uncached allocator (arch/ia64/kernel/uncached.c) is also required. Both Andrey Volkov and Jes Sorenson have expressed a desire that the gen_pool allocator not write to the memory being managed. See the following: http://marc.theaimsgroup.com/?l=linux-kernel&m=113518602713125&w=2 http://marc.theaimsgroup.com/?l=linux-kernel&m=113533568827916&w=2 Signed-off-by: Dean Nelson <dcn@sgi.com> Cc: Andrey Volkov <avolkov@varma-el.com> Acked-by: Jes Sorensen <jes@trained-monkey.org> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] ia64 uncached allocJes Sorensen
This patch contains the ia64 uncached page allocator and the generic allocator (genalloc). The uncached allocator was formerly part of the SN2 mspec driver but there are several other users of it so it has been split off from the driver. The generic allocator can be used by device driver to manage special memory etc. The generic allocator is based on the allocator from the sym53c8xx_2 driver. Various users on ia64 needs uncached memory. The SGI SN architecture requires it for inter-partition communication between partitions within a large NUMA cluster. The specific user for this is the XPC code. Another application is large MPI style applications which use it for synchronization, on SN this can be done using special 'fetchop' operations but it also benefits non SN hardware which may use regular uncached memory for this purpose. Performance of doing this through uncached vs cached memory is pretty substantial. This is handled by the mspec driver which I will push out in a seperate patch. Rather than creating a specific allocator for just uncached memory I came up with genalloc which is a generic purpose allocator that can be used by device drivers and other subsystems as they please. For instance to handle onboard device memory. It was derived from the sym53c7xx_2 driver's allocator which is also an example of a potential user (I am refraining from modifying sym2 right now as it seems to have been under fairly heavy development recently). On ia64 memory has various properties within a granule, ie. it isn't safe to access memory as uncached within the same granule as currently has memory accessed in cached mode. The regular system therefore doesn't utilize memory in the lower granules which is mixed in with device PAL code etc. The uncached driver walks the EFI memmap and pulls out the spill uncached pages and sticks them into the uncached pool. Only after these chunks have been utilized, will it start converting regular cached memory into uncached memory. Hence the reason for the EFI related code additions. Signed-off-by: Jes Sorensen <jes@wildopensource.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>