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* lib/genalloc.c: start search from start of chunkDaniel Mentz2016-10-271-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | gen_pool_alloc_algo() iterates over the chunks of a pool trying to find a contiguous block of memory that satisfies the allocation request. The shortcut if (size > atomic_read(&chunk->avail)) continue; makes the loop skip over chunks that do not have enough bytes left to fulfill the request. There are two situations, though, where an allocation might still fail: (1) The available memory is not contiguous, i.e. the request cannot be fulfilled due to external fragmentation. (2) A race condition. Another thread runs the same code concurrently and is quicker to grab the available memory. In those situations, the loop calls pool->algo() to search the entire chunk, and pool->algo() returns some value that is >= end_bit to indicate that the search failed. This return value is then assigned to start_bit. The variables start_bit and end_bit describe the range that should be searched, and this range should be reset for every chunk that is searched. Today, the code fails to reset start_bit to 0. As a result, prefixes of subsequent chunks are ignored. Memory allocations might fail even though there is plenty of room left in these prefixes of those other chunks. Fixes: 7f184275aa30 ("lib, Make gen_pool memory allocator lockless") Link: http://lkml.kernel.org/r/1477420604-28918-1-git-send-email-danielmentz@google.com Signed-off-by: Daniel Mentz <danielmentz@google.com> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* CPM/QE: use genalloc to manage CPM/QE muramZhao Qiang2015-12-221-1/+1
| | | | | | | Use genalloc to manage CPM/QE muram instead of rheap. Signed-off-by: Zhao Qiang <qiang.zhao@freescale.com> Signed-off-by: Scott Wood <scottwood@freescale.com>
* genalloc:support allocating specific regionZhao Qiang2015-12-221-0/+32
| | | | | | | | 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>
* genalloc:support memory-allocation with bytes-alignment to genallocZhao Qiang2015-12-221-6/+55
| | | | | | | | | | | 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>
* genalloc: add support of multiple gen_pools per deviceVladimir Zapolskiy2015-09-041-14/+57
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* genalloc: add name arg to gen_pool_get() and devm_gen_pool_create()Vladimir Zapolskiy2015-09-041-21/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* genalloc: rename of_get_named_gen_pool() to of_gen_pool_get()Vladimir Zapolskiy2015-06-301-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* genalloc: rename dev_get_gen_pool() to gen_pool_get()Vladimir Zapolskiy2015-06-301-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* lib/genalloc.c: check result of devres_alloc()Jan Kara2015-02-131-0/+2
| | | | | | | | | | | | devm_gen_pool_create() calls devres_alloc() and dereferences its result without checking whether devres_alloc() succeeded. Check for error and bail out if it happened. Coverity-id 1016493. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/genalloc.c: remove redundant includeRasmus Villemoes2015-02-121-1/+0
| | | | | | | | | Removing this include produces byte-identical output, and thus removes a false dependency. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/genalloc.c: fix the end addr check in addr_in_gen_pool()Toshi Kikuchi2015-02-121-1/+1
| | | | | | | | | Since chunk->end_addr is (chunk->start_addr + size - 1), the end address to compare should be (start + size - 1). Signed-off-by: Toshi Kikuchi <toshik@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/genalloc.c: export devm_gen_pool_create() for modulesMichal Simek2014-12-031-0/+1
| | | | | | | | | | | | | | | Modules can use this function for creating pool. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Acked-by: Lad, Prabhakar <prabhakar.csengg@gmail.com> Cc: Laura Abbott <lauraa@codeaurora.org> Cc: Olof Johansson <olof@lixom.net> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> Cc: Philipp Zabel <p.zabel@pengutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/genalloc.c: add genpool range check functionLaura Abbott2014-10-091-0/+29
| | | | | | | | | | | | | | | | | | | 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>
* lib/genalloc.c: add power aligned algorithmLaura Abbott2014-10-091-0/+20
| | | | | | | | | | | | | | | | | | 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>
* genalloc: fix device node resource counterVladimir Zapolskiy2014-09-261-0/+1
| | | | | | | | | | | | Decrement the np_pool device_node refcount, which was incremented on the preceding of_parse_phandle() call. Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Olof Johansson <olof@lixom.net> Cc: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/genalloc.c: add check gen_pool_dma_alloc() if dma pointer is not NULLLad, Prabhakar2014-01-291-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the gen_pool_dma_alloc() the dma pointer can be NULL and while assigning gen_pool_virt_to_phys(pool, vaddr) to dma caused the following crash on da850 evm: Unable to handle kernel NULL pointer dereference at virtual address 00000000 Internal error: Oops: 805 [#1] PREEMPT ARM Modules linked in: CPU: 0 PID: 1 Comm: swapper Tainted: G W 3.13.0-rc1-00001-g0609e45-dirty #5 task: c4830000 ti: c4832000 task.ti: c4832000 PC is at gen_pool_dma_alloc+0x30/0x3c LR is at gen_pool_virt_to_phys+0x74/0x80 Process swapper, call trace: gen_pool_dma_alloc+0x30/0x3c davinci_pm_probe+0x40/0xa8 platform_drv_probe+0x1c/0x4c driver_probe_device+0x98/0x22c __driver_attach+0x8c/0x90 bus_for_each_dev+0x6c/0x8c bus_add_driver+0x124/0x1d4 driver_register+0x78/0xf8 platform_driver_probe+0x20/0xa4 davinci_init_late+0xc/0x14 init_machine_late+0x1c/0x28 do_one_initcall+0x34/0x15c kernel_init_freeable+0xe4/0x1ac kernel_init+0x8/0xec This patch fixes the above. [akpm@linux-foundation.org: update kerneldoc] Signed-off-by: Lad, Prabhakar <prabhakar.csengg@gmail.com> Cc: Philipp Zabel <p.zabel@pengutronix.de> Cc: Nicolin Chen <b42378@freescale.com> Cc: Joe Perches <joe@perches.com> Cc: Sachin Kamat <sachin.kamat@linaro.org> Cc: <stable@vger.kernel.org> [3.13.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/genalloc: add a helper function for DMA buffer allocationNicolin Chen2013-11-131-0/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* lib/genalloc.c: correct dev_get_gen_pool documentationEmilio López2013-09-111-1/+0
| | | | | | | | | The documentation mentions a "name" parameter, which does not exist. This commit removes such mention from the function documentation. Signed-off-by: Emilio López <emilio@elopez.com.ar> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/genalloc.c: convert kmalloc_node(...GFP_ZERO...) to kzalloc_node(...)Joe Perches2013-09-111-1/+1
| | | | | | | | Use the helper function instead of __GFP_ZERO. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/genalloc.c: fix overflow of ending address of memory chunkJoonyoung Shim2013-09-111-7/+12
| | | | | | | | | | | | | | | | | | | 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>
* genalloc: add devres support, allow to find a managed pool by devicePhilipp Zabel2013-04-291-0/+81
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* genalloc: stop crashing the system when destroying a poolThadeu Lima de Souza Cascardo2012-10-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The genalloc code uses the bitmap API from include/linux/bitmap.h and lib/bitmap.c, which is based on long values. Both bitmap_set from lib/bitmap.c and bitmap_set_ll, which is the lockless version from genalloc.c, use BITMAP_LAST_WORD_MASK to set the first bits in a long in the bitmap. That one uses (1 << bits) - 1, 0b111, if you are setting the first three bits. This means that the API counts from the least significant bits (LSB from now on) to the MSB. The LSB in the first long is bit 0, then. The same works for the lookup functions. The genalloc code uses longs for the bitmap, as it should. In include/linux/genalloc.h, struct gen_pool_chunk has unsigned long bits[0] as its last member. When allocating the struct, genalloc should reserve enough space for the bitmap. This should be a proper number of longs that can fit the amount of bits in the bitmap. However, genalloc allocates an integer number of bytes that fit the amount of bits, but may not be an integer amount of longs. 9 bytes, for example, could be allocated for 70 bits. This is a problem in itself if the Least Significat Bit in a long is in the byte with the largest address, which happens in Big Endian machines. This means genalloc is not allocating the byte in which it will try to set or check for a bit. This may end up in memory corruption, where genalloc will try to set the bits it has not allocated. In fact, genalloc may not set these bits because it may find them already set, because they were not zeroed since they were not allocated. And that's what causes a BUG when gen_pool_destroy is called and check for any set bits. What really happens is that genalloc uses kmalloc_node with __GFP_ZERO on gen_pool_add_virt. With SLAB and SLUB, this means the whole slab will be cleared, not only the requested bytes. Since struct gen_pool_chunk has a size that is a multiple of 8, and slab sizes are multiples of 8, we get lucky and allocate and clear the right amount of bytes. Hower, this is not the case with SLOB or with older code that did memset after allocating instead of using __GFP_ZERO. So, a simple module as this (running 3.6.0), will cause a crash when rmmod'ed. [root@phantom-lp2 foo]# cat foo.c #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/genalloc.h> MODULE_LICENSE("GPL"); MODULE_VERSION("0.1"); static struct gen_pool *foo_pool; static __init int foo_init(void) { int ret; foo_pool = gen_pool_create(10, -1); if (!foo_pool) return -ENOMEM; ret = gen_pool_add(foo_pool, 0xa0000000, 32 << 10, -1); if (ret) { gen_pool_destroy(foo_pool); return ret; } return 0; } static __exit void foo_exit(void) { gen_pool_destroy(foo_pool); } module_init(foo_init); module_exit(foo_exit); [root@phantom-lp2 foo]# zcat /proc/config.gz | grep SLOB CONFIG_SLOB=y [root@phantom-lp2 foo]# insmod ./foo.ko [root@phantom-lp2 foo]# rmmod foo ------------[ cut here ]------------ kernel BUG at lib/genalloc.c:243! cpu 0x4: Vector: 700 (Program Check) at [c0000000bb0e7960] pc: c0000000003cb50c: .gen_pool_destroy+0xac/0x110 lr: c0000000003cb4fc: .gen_pool_destroy+0x9c/0x110 sp: c0000000bb0e7be0 msr: 8000000000029032 current = 0xc0000000bb0e0000 paca = 0xc000000006d30e00 softe: 0 irq_happened: 0x01 pid = 13044, comm = rmmod kernel BUG at lib/genalloc.c:243! [c0000000bb0e7ca0] d000000004b00020 .foo_exit+0x20/0x38 [foo] [c0000000bb0e7d20] c0000000000dff98 .SyS_delete_module+0x1a8/0x290 [c0000000bb0e7e30] c0000000000097d4 syscall_exit+0x0/0x94 --- Exception: c00 (System Call) at 000000800753d1a0 SP (fffd0b0e640) is in userspace Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Benjamin Gaignard <benjamin.gaignard@stericsson.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* genalloc: make it possible to use a custom allocation algorithmBenjamin Gaignard2012-10-061-4/+84
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* lib: reduce the use of module.h wherever possiblePaul Gortmaker2012-03-071-1/+1
| | | | | | | | | | For files only using THIS_MODULE and/or EXPORT_SYMBOL, map them onto including export.h -- or if the file isn't even using those, then just delete the include. Fix up any implicit include dependencies that were being masked by module.h along the way. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* lib, Make gen_pool memory allocator locklessHuang Ying2011-08-031-57/+243
| | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* lib/genalloc.c: add support for specifying the physical addressJean-Christophe PLAGNIOL-VILLARD2011-05-251-8/+37
| | | | | | | | | | | | | | 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>
* genalloc: fix allocation from end of poolImre Deak2010-06-291-1/+0
| | | | | | | | | | | | | | | | bitmap_find_next_zero_area requires the size of the bitmap, we instead passed the last suitable position. This made it impossible to allocate from the end of the pool. Fixes a regression introduced by 243797f59b748f679ab88d456fcc4f92236d724b ("genalloc: use bitmap_find_next_zero_area"). Signed-off-by: Imre Deak <imre.deak@nokia.com> Cc: Zygo Blaxell <zygo.blaxell@xandros.com> Cc: Tejun Heo <tj@kernel.org> Acked-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* genalloc: use bitmap_find_next_zero_areaAkinobu Mita2009-12-161-21/+12
| | | | | | Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/genalloc.c: remove unmatched write_lock() in gen_pool_destroyZygo Blaxell2009-06-161-1/+0
| | | | | | | | | | | | | | | There is a call to write_lock() in gen_pool_destroy which is not balanced by any corresponding write_unlock(). This causes problems with preemption because the preemption-disable counter is incremented in the write_lock() call, but never decremented by any call to write_unlock(). This bug is gen_pool_destroy, and one of them is non-x86 arch-specific code. Signed-off-by: Zygo Blaxell <zygo.blaxell@xandros.com> Cc: Jiri Kosina <trivial@kernel.org> Cc: Steve Wise <swise@opengridcomputing.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Slab allocators: Replace explicit zeroing with __GFP_ZEROChristoph Lameter2007-07-171-2/+1
| | | | | | | | | | | | | kmalloc_node() and kmem_cache_alloc_node() were not available in a zeroing variant in the past. But with __GFP_ZERO it is possible now to do zeroing while allocating. Use __GFP_ZERO to remove the explicit clearing of memory via memset whereever we can. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] genalloc warning fixesAndrew Morton2007-02-201-2/+2
| | | | | | | | | | lib/genalloc.c: In function 'gen_pool_alloc': lib/genalloc.c:151: warning: passing argument 2 of '__set_bit' from incompatible pointer type lib/genalloc.c: In function 'gen_pool_free': lib/genalloc.c:190: warning: passing argument 2 of '__clear_bit' from incompatible pointer type Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] make genpool allocator adhere to kernel-doc standardsDean Nelson2006-10-021-20/+23
| | | | | | | | | | | The exported kernel interfaces of genpool allocator need to adhere to the requirements of kernel-doc. Signed-off-by: Dean Nelson <dcn@sgi.com> Cc: Steve Wise <swise@opengridcomputing.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] LIB: add gen_pool_destroy()Steve Wise2006-10-021-0/+30
| | | | | | | | | | | 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>
* [PATCH] change gen_pool allocator to not touch managed memoryDean Nelson2006-06-231-142/+121
| | | | | | | | | | | | | | | | | | | | | | | 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>
* [PATCH] fix broken lib/genalloc.cChris Humbert2005-11-281-8/+6
| | | | | | | | | | genalloc improperly stores the sizes of freed chunks, allocates overlapping memory regions, and oopses after its in-band data is overwritten. Signed-off-by: Chris Humbert <mahadri-kernel@drigon.com> Cc: Jes Sorensen <jes@trained-monkey.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] ia64 uncached allocJes Sorensen2005-06-211-0/+188
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>
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