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2020-10-29lib/scatterlist: use consistent sg_copy_buffer() return typeDavid Disseldorp1-1/+1
sg_copy_buffer() returns a size_t with the number of bytes copied. Return 0 instead of false if the copy is skipped. Signed-off-by: David Disseldorp <ddiss@suse.de> Reviewed-by: Douglas Gilbert <dgilbert@interlog.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-24Merge tag 'block-5.10-2020-10-24' of git://git.kernel.dk/linux-blockLinus Torvalds1-1/+1
Pull block fixes from Jens Axboe: - NVMe pull request from Christoph - rdma error handling fixes (Chao Leng) - fc error handling and reconnect fixes (James Smart) - fix the qid displace when tracing ioctl command (Keith Busch) - don't use BLK_MQ_REQ_NOWAIT for passthru (Chaitanya Kulkarni) - fix MTDT for passthru (Logan Gunthorpe) - blacklist Write Same on more devices (Kai-Heng Feng) - fix an uninitialized work struct (zhenwei pi)" - lightnvm out-of-bounds fix (Colin) - SG allocation leak fix (Doug) - rnbd fixes (Gioh, Guoqing, Jack) - zone error translation fixes (Keith) - kerneldoc markup fix (Mauro) - zram lockdep fix (Peter) - Kill unused io_context members (Yufen) - NUMA memory allocation cleanup (Xianting) - NBD config wakeup fix (Xiubo) * tag 'block-5.10-2020-10-24' of git://git.kernel.dk/linux-block: (27 commits) block: blk-mq: fix a kernel-doc markup nvme-fc: shorten reconnect delay if possible for FC nvme-fc: wait for queues to freeze before calling update_hr_hw_queues nvme-fc: fix error loop in create_hw_io_queues nvme-fc: fix io timeout to abort I/O null_blk: use zone status for max active/open nvmet: don't use BLK_MQ_REQ_NOWAIT for passthru nvmet: cleanup nvmet_passthru_map_sg() nvmet: limit passthru MTDS by BIO_MAX_PAGES nvmet: fix uninitialized work for zero kato nvme-pci: disable Write Zeroes on Sandisk Skyhawk nvme: use queuedata for nvme_req_qid nvme-rdma: fix crash due to incorrect cqe nvme-rdma: fix crash when connect rejected block: remove unused members for io_context blk-mq: remove the calling of local_memory_node() zram: Fix __zram_bvec_{read,write}() locking order skd_main: remove unused including <linux/version.h> sgl_alloc_order: fix memory leak lightnvm: fix out-of-bounds write to array devices->info[] ...
2020-10-17Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdmaLinus Torvalds1-26/+107
Pull rdma updates from Jason Gunthorpe: "A usual cycle for RDMA with a typical mix of driver and core subsystem updates: - Driver minor changes and bug fixes for mlx5, efa, rxe, vmw_pvrdma, hns, usnic, qib, qedr, cxgb4, hns, bnxt_re - Various rtrs fixes and updates - Bug fix for mlx4 CM emulation for virtualization scenarios where MRA wasn't working right - Use tracepoints instead of pr_debug in the CM code - Scrub the locking in ucma and cma to close more syzkaller bugs - Use tasklet_setup in the subsystem - Revert the idea that 'destroy' operations are not allowed to fail at the driver level. This proved unworkable from a HW perspective. - Revise how the umem API works so drivers make fewer mistakes using it - XRC support for qedr - Convert uverbs objects RWQ and MW to new the allocation scheme - Large queue entry sizes for hns - Use hmm_range_fault() for mlx5 On Demand Paging - uverbs APIs to inspect the GID table instead of sysfs - Move some of the RDMA code for building large page SGLs into lib/scatterlist" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (191 commits) RDMA/ucma: Fix use after free in destroy id flow RDMA/rxe: Handle skb_clone() failure in rxe_recv.c RDMA/rxe: Move the definitions for rxe_av.network_type to uAPI RDMA: Explicitly pass in the dma_device to ib_register_device lib/scatterlist: Do not limit max_segment to PAGE_ALIGNED values IB/mlx4: Convert rej_tmout radix-tree to XArray RDMA/rxe: Fix bug rejecting all multicast packets RDMA/rxe: Fix skb lifetime in rxe_rcv_mcast_pkt() RDMA/rxe: Remove duplicate entries in struct rxe_mr IB/hfi,rdmavt,qib,opa_vnic: Update MAINTAINERS IB/rdmavt: Fix sizeof mismatch MAINTAINERS: CISCO VIC LOW LATENCY NIC DRIVER RDMA/bnxt_re: Fix sizeof mismatch for allocation of pbl_tbl. RDMA/bnxt_re: Use rdma_umem_for_each_dma_block() RDMA/umem: Move to allocate SG table from pages lib/scatterlist: Add support in dynamic allocation of SG table from pages tools/testing/scatterlist: Show errors in human readable form tools/testing/scatterlist: Rejuvenate bit-rotten test RDMA/ipoib: Set rtnl_link_ops for ipoib interfaces RDMA/uverbs: Expose the new GID query API to user space ...
2020-10-16lib/scatterlist.c: avoid a double memsetChristophe JAILLET1-1/+1
'sgl' is zeroed a few lines below in 'sg_init_table()'. There is no need to clear it twice. Remove the redundant initialization. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Link: https://lkml.kernel.org/r/20200920071544.368841-1-christophe.jaillet@wanadoo.fr Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16lib/scatterlist: Do not limit max_segment to PAGE_ALIGNED valuesJason Gunthorpe1-4/+8
The main intention of the max_segment argument to __sg_alloc_table_from_pages() is to match the DMA layer segment size set by dma_set_max_seg_size(). Restricting the input to be page aligned makes it impossible to just connect the DMA layer to this API. The only reason for a page alignment here is because the algorithm will overshoot the max_segment if it is not a multiple of PAGE_SIZE. Simply fix the alignment before starting and don't expose this implementation detail to the callers. A future patch will completely remove SCATTERLIST_MAX_SEGMENT. Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-10-16sgl_alloc_order: fix memory leakDouglas Gilbert1-1/+1
sgl_alloc_order() can fail when 'length' is large on a memory constrained system. When order > 0 it will potentially be making several multi-page allocations with the later ones more likely to fail than the earlier one. So it is important that sgl_alloc_order() frees up any pages it has obtained before returning NULL. In the case when order > 0 it calls the wrong free page function and leaks. In testing the leak was sufficient to bring down my 8 GiB laptop with OOM. Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-10-05lib/scatterlist: Add support in dynamic allocation of SG table from pagesMaor Gottlieb1-24/+101
Extend __sg_alloc_table_from_pages to support dynamic allocation of SG table from pages. It should be used by drivers that can't supply all the pages at one time. This function returns the last populated SGE in the table. Users should pass it as an argument to the function from the second call and forward. As before, nents will be equal to the number of populated SGEs (chunks). With this new extension, drivers can benefit the optimization of merging contiguous pages without a need to allocate all pages in advance and hold them in a large buffer. E.g. with the Infiniband driver that allocates a single page for hold the pages. For 1TB memory registration, the temporary buffer would consume only 4KB, instead of 2GB. Link: https://lore.kernel.org/r/20201004154340.1080481-2-leon@kernel.org Signed-off-by: Maor Gottlieb <maorg@nvidia.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2020-04-07lib/scatterlist: fix sg_copy_buffer() kerneldocGeert Uytterhoeven1-1/+1
Add the missing closing parenthesis to the description for the to_buffer parameter of sg_copy_buffer(). Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Akinobu Mita <akinobu.mita@gmail.com Link: http://lkml.kernel.org/r/20200212084241.8778-1-geert+renesas@glider.be Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-31lib/scatterlist.c: adjust indentation in __sg_alloc_tableNathan Chancellor1-1/+1
Clang warns: ../lib/scatterlist.c:314:5: warning: misleading indentation; statement is not part of the previous 'if' [-Wmisleading-indentation] return -ENOMEM; ^ ../lib/scatterlist.c:311:4: note: previous statement is here if (prv) ^ 1 warning generated. This warning occurs because there is a space before the tab on this line. Remove it so that the indentation is consistent with the Linux kernel coding style and clang no longer warns. Link: http://lkml.kernel.org/r/20191218033606.11942-1-natechancellor@gmail.com Link: https://github.com/ClangBuiltLinux/linux/issues/830 Fixes: edce6820a9fd ("scatterlist: prevent invalid free when alloc fails") Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-11Merge tag 'scsi-sg' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds1-13/+23
Pull SCSI scatter-gather list updates from James Bottomley: "This topic branch covers a fundamental change in how our sg lists are allocated to make mq more efficient by reducing the size of the preallocated sg list. This necessitates a large number of driver changes because the previous guarantee that if a driver specified SG_ALL as the size of its scatter list, it would get a non-chained list and didn't need to bother with scatterlist iterators is now broken and every driver *must* use scatterlist iterators. This was broken out as a separate topic because we need to convert all the drivers before pulling the trigger and unconverted drivers kept being found, necessitating a rebase" * tag 'scsi-sg' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (21 commits) scsi: core: don't preallocate small SGL in case of NO_SG_CHAIN scsi: lib/sg_pool.c: clear 'first_chunk' in case of no preallocation scsi: core: avoid preallocating big SGL for data scsi: core: avoid preallocating big SGL for protection information scsi: lib/sg_pool.c: improve APIs for allocating sg pool scsi: esp: use sg helper to iterate over scatterlist scsi: NCR5380: use sg helper to iterate over scatterlist scsi: wd33c93: use sg helper to iterate over scatterlist scsi: ppa: use sg helper to iterate over scatterlist scsi: pcmcia: nsp_cs: use sg helper to iterate over scatterlist scsi: imm: use sg helper to iterate over scatterlist scsi: aha152x: use sg helper to iterate over scatterlist scsi: s390: zfcp_fc: use sg helper to iterate over scatterlist scsi: staging: unisys: visorhba: use sg helper to iterate over scatterlist scsi: usb: image: microtek: use sg helper to iterate over scatterlist scsi: pmcraid: use sg helper to iterate over scatterlist scsi: ipr: use sg helper to iterate over scatterlist scsi: mvumi: use sg helper to iterate over scatterlist scsi: lpfc: use sg helper to iterate over scatterlist scsi: advansys: use sg helper to iterate over scatterlist ...
2019-07-08Merge branch 'linus' of ↵Linus Torvalds1-4/+5
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto updates from Herbert Xu: "Here is the crypto update for 5.3: API: - Test shash interface directly in testmgr - cra_driver_name is now mandatory Algorithms: - Replace arc4 crypto_cipher with library helper - Implement 5 way interleave for ECB, CBC and CTR on arm64 - Add xxhash - Add continuous self-test on noise source to drbg - Update jitter RNG Drivers: - Add support for SHA204A random number generator - Add support for 7211 in iproc-rng200 - Fix fuzz test failures in inside-secure - Fix fuzz test failures in talitos - Fix fuzz test failures in qat" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (143 commits) crypto: stm32/hash - remove interruptible condition for dma crypto: stm32/hash - Fix hmac issue more than 256 bytes crypto: stm32/crc32 - rename driver file crypto: amcc - remove memset after dma_alloc_coherent crypto: ccp - Switch to SPDX license identifiers crypto: ccp - Validate the the error value used to index error messages crypto: doc - Fix formatting of new crypto engine content crypto: doc - Add parameter documentation crypto: arm64/aes-ce - implement 5 way interleave for ECB, CBC and CTR crypto: arm64/aes-ce - add 5 way interleave routines crypto: talitos - drop icv_ool crypto: talitos - fix hash on SEC1. crypto: talitos - move struct talitos_edesc into talitos.h lib/scatterlist: Fix mapping iterator when sg->offset is greater than PAGE_SIZE crypto/NX: Set receive window credits to max number of CRBs in RxFIFO crypto: asymmetric_keys - select CRYPTO_HASH where needed crypto: serpent - mark __serpent_setkey_sbox noinline crypto: testmgr - dynamically allocate crypto_shash crypto: testmgr - dynamically allocate testvec_config crypto: talitos - eliminate unneeded 'done' functions at build time ...
2019-07-03lib/scatterlist: Fix mapping iterator when sg->offset is greater than PAGE_SIZEChristophe Leroy1-4/+5
All mapping iterator logic is based on the assumption that sg->offset is always lower than PAGE_SIZE. But there are situations where sg->offset is such that the SG item is on the second page. In that case sg_copy_to_buffer() fails properly copying the data into the buffer. One of the reason is that the data will be outside the kmapped area used to access that data. This patch fixes the issue by adjusting the mapping iterator offset and pgoffset fields such that offset is always lower than PAGE_SIZE. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Fixes: 4225fc8555a9 ("lib/scatterlist: use page iterator in the mapping iterator") Cc: stable@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-06-20scsi: lib/sg_pool.c: improve APIs for allocating sg poolMing Lei1-13/+23
sg_alloc_table_chained() currently allows the caller to provide one preallocated SGL and returns if the requested number isn't bigger than size of that SGL. This is used to inline an SGL for an IO request. However, scattergather code only allows that size of the 1st preallocated SGL to be SG_CHUNK_SIZE(128). This means a substantial amount of memory (4KB) is claimed for the SGL for each IO request. If the I/O is small, it would be prudent to allocate a smaller SGL. Introduce an extra parameter to sg_alloc_table_chained() and sg_free_table_chained() for specifying size of the preallocated SGL. Both __sg_free_table() and __sg_alloc_table() assume that each SGL has the same size except for the last one. Change the code to allow both functions to accept a variable size for the 1st preallocated SGL. [mkp: attempted to clarify commit desc] Cc: Christoph Hellwig <hch@lst.de> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Ewan D. Milne <emilne@redhat.com> Cc: Hannes Reinecke <hare@suse.com> Cc: Sagi Grimberg <sagi@grimberg.me> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: netdev@vger.kernel.org Cc: linux-nvme@lists.infradead.org Suggested-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230Thomas Gleixner1-3/+1
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>
2019-02-11lib/scatterlist: Provide a DMA page iteratorJason Gunthorpe1-0/+26
Commit 2db76d7c3c6d ("lib/scatterlist: sg_page_iter: support sg lists w/o backing pages") introduced the sg_page_iter_dma_address() function without providing a way to use it in the general case. If the sg_dma_len() is not equal to the sg length callers cannot safely use the for_each_sg_page/sg_page_iter_dma_address combination. Resolve this API mistake by providing a DMA specific iterator, for_each_sg_dma_page(), that uses the right length so sg_page_iter_dma_address() works as expected with all sglists. A new iterator type is introduced to provide compile-time safety against wrongly mixing accessors and iterators. Acked-by: Christoph Hellwig <hch@lst.de> (for scatterlist) Acked-by: Thomas Hellstrom <thellstrom@vmware.com> Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com> (ipu3-cio2) Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-12-06arch: switch the default on ARCH_HAS_SG_CHAINChristoph Hellwig1-1/+1
These days architectures are mostly out of the business of dealing with struct scatterlist at all, unless they have architecture specific iommu drivers. Replace the ARCH_HAS_SG_CHAIN symbol with a ARCH_NO_SG_CHAIN one only enabled for architectures with horrible legacy iommu drivers like alpha and parisc, and conditionally for arm which wants to keep it disable for legacy platforms. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
2018-06-30Merge tag 'for-linus-20180629' of git://git.kernel.dk/linux-blockLinus Torvalds1-6/+0
Pull block fixes from Jens Axboe: "Small set of fixes for this series. Mostly just minor fixes, the only oddball in here is the sg change. The sg change came out of the stall fix for NVMe, where we added a mempool and limited us to a single page allocation. CONFIG_SG_DEBUG sort-of ruins that, since we'd need to account for that. That's actually a generic problem, since lots of drivers need to allocate SG lists. So this just removes support for CONFIG_SG_DEBUG, which I added back in 2007 and to my knowledge it was never useful. Anyway, outside of that, this pull contains: - clone of request with special payload fix (Bart) - drbd discard handling fix (Bart) - SATA blk-mq stall fix (me) - chunk size fix (Keith) - double free nvme rdma fix (Sagi)" * tag 'for-linus-20180629' of git://git.kernel.dk/linux-block: sg: remove ->sg_magic member drbd: Fix drbd_request_prepare() discard handling blk-mq: don't queue more if we get a busy return block: Fix cloning of requests with a special payload nvme-rdma: fix possible double free of controller async event buffer block: Fix transfer when chunk sectors exceeds max
2018-06-29sg: remove ->sg_magic memberJens Axboe1-6/+0
This was introduced more than a decade ago when sg chaining was added, but we never really caught anything with it. The scatterlist entry size can be critical, since drivers allocate it, so remove the magic member. Recently it's been triggering allocation stalls and failures in NVMe. Tested-by: Jordan Glover <Golden_Miller83@protonmail.ch> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-12treewide: kmalloc() -> kmalloc_array()Kees Cook1-1/+2
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This patch replaces cases of: kmalloc(a * b, gfp) with: kmalloc_array(a * b, gfp) as well as handling cases of: kmalloc(a * b * c, gfp) with: kmalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kmalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kmalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The tools/ directory was manually excluded, since it has its own implementation of kmalloc(). The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(char) * COUNT + COUNT , ...) | kmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kmalloc + kmalloc_array ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kmalloc(C1 * C2 * C3, ...) | kmalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kmalloc(sizeof(THING) * C2, ...) | kmalloc(sizeof(TYPE) * C2, ...) | kmalloc(C1 * C2 * C3, ...) | kmalloc(C1 * C2, ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - (E1) * E2 + E1, E2 , ...) | - kmalloc + kmalloc_array ( - (E1) * (E2) + E1, E2 , ...) | - kmalloc + kmalloc_array ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-03-30lib/scatterlist: add sg_init_marker() helperPrashant Bhole1-8/+1
sg_init_marker initializes sg_magic in the sg table and calls sg_mark_end() on the last entry of the table. This can be useful to avoid memset in sg_init_table() when scatterlist is already zeroed out For example: when scatterlist is embedded inside other struct and that container struct is zeroed out Suggested-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Prashant Bhole <bhole_prashant_q7@lab.ntt.co.jp> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-01-19lib/scatterlist: Fix chaining support in sgl_alloc_order()Bart Van Assche1-5/+27
This patch avoids that workloads with large block sizes (megabytes) can trigger the following call stack with the ib_srpt driver (that driver is the only driver that chains scatterlists allocated by sgl_alloc_order()): BUG: Bad page state in process kworker/0:1H pfn:2423a78 page:fffffb03d08e9e00 count:-3 mapcount:0 mapping: (null) index:0x0 flags: 0x57ffffc0000000() raw: 0057ffffc0000000 0000000000000000 0000000000000000 fffffffdffffffff raw: dead000000000100 dead000000000200 0000000000000000 0000000000000000 page dumped because: nonzero _count CPU: 0 PID: 733 Comm: kworker/0:1H Tainted: G I 4.15.0-rc7.bart+ #1 Hardware name: HP ProLiant DL380 G7, BIOS P67 08/16/2015 Workqueue: ib-comp-wq ib_cq_poll_work [ib_core] Call Trace: dump_stack+0x5c/0x83 bad_page+0xf5/0x10f get_page_from_freelist+0xa46/0x11b0 __alloc_pages_nodemask+0x103/0x290 sgl_alloc_order+0x101/0x180 target_alloc_sgl+0x2c/0x40 [target_core_mod] srpt_alloc_rw_ctxs+0x173/0x2d0 [ib_srpt] srpt_handle_new_iu+0x61e/0x7f0 [ib_srpt] __ib_process_cq+0x55/0xa0 [ib_core] ib_cq_poll_work+0x1b/0x60 [ib_core] process_one_work+0x141/0x340 worker_thread+0x47/0x3e0 kthread+0xf5/0x130 ret_from_fork+0x1f/0x30 Fixes: e80a0af4759a ("lib/scatterlist: Introduce sgl_alloc() and sgl_free()") Reported-by: Laurence Oberman <loberman@redhat.com> Tested-by: Laurence Oberman <loberman@redhat.com> Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Cc: Nicholas A. Bellinger <nab@linux-iscsi.org> Cc: Laurence Oberman <loberman@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-06lib/scatterlist: Introduce sgl_alloc() and sgl_free()Bart Van Assche1-0/+105
Many kernel drivers contain code that allocates and frees both a scatterlist and the pages that populate that scatterlist. Introduce functions in lib/scatterlist.c that perform these tasks instead of duplicating this functionality in multiple drivers. Only include these functions in the build if CONFIG_SGL_ALLOC=y to avoid that the kernel size increases if this functionality is not used. Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-07lib/scatterlist: Introduce and export __sg_alloc_table_from_pagesTvrtko Ursulin1-17/+49
Drivers like i915 benefit from being able to control the maxium size of the sg coalesced segment while building the scatter- gather list. Introduce and export the __sg_alloc_table_from_pages function which will allow it that control. v2: Reorder parameters. (Chris Wilson) v3: Fix incomplete reordering in v2. v4: max_segment needs to be page aligned. v5: Rebase. v6: Rebase. v7: Fix spelling in commit and mention max segment size in __sg_alloc_table_from_pages kerneldoc. (Andrew Morton) Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: linux-kernel@vger.kernel.org Cc: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Link: https://patchwork.freedesktop.org/patch/msgid/20170803091351.23594-1-tvrtko.ursulin@linux.intel.com
2017-09-07lib/scatterlist: Avoid potential scatterlist entry overflowTvrtko Ursulin1-11/+20
Since the scatterlist length field is an unsigned int, make sure that sg_alloc_table_from_pages does not overflow it while coalescing pages to a single entry. v2: Drop reference to future use. Use UINT_MAX. v3: max_segment must be page aligned. v4: Do not rely on compiler to optimise out the rounddown. (Joonas Lahtinen) v5: Simplified loops and use post-increments rather than pre-increments. Use PAGE_MASK and fix comment typo. (Andy Shevchenko) v6: Commit spelling fix. Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: linux-kernel@vger.kernel.org Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170803091312.22875-1-tvrtko.ursulin@linux.intel.com
2017-09-07lib/scatterlist: Fix offset type in sg_alloc_table_from_pagesTvrtko Ursulin1-1/+1
Scatterlist entries have an unsigned int for the offset so correct the sg_alloc_table_from_pages function accordingly. Since these are offsets withing a page, unsigned int is wide enough. Also converts callers which were using unsigned long locally with the lower_32_bits annotation to make it explicitly clear what is happening. v2: Use offset_in_page. (Chris Wilson) Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Pawel Osciak <pawel@osciak.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Cc: Tomasz Stanislawski <t.stanislaws@samsung.com> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: Alexandre Bounine <alexandre.bounine@idt.com> Cc: linux-media@vger.kernel.org Cc: linux-kernel@vger.kernel.org Acked-by: Marek Szyprowski <m.szyprowski@samsung.com> (v1) Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Link: https://patchwork.freedesktop.org/patch/msgid/20170731185512.20010-1-tvrtko.ursulin@linux.intel.com
2017-06-15scatterlist: add sg_zero_buffer() helperJohannes Thumshirn1-0/+35
The sg_zero_buffer() helper is used to zero fill an area in a SG list. Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> [hch: renamed to sg_zero_buffer] Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-02-27scatterlist: do not disable IRQs in sg_copy_bufferGilad Ben-Yossef1-4/+0
Commit 50bed2e2862a ("sg: disable interrupts inside sg_copy_buffer") introduced disabling interrupts in sg_copy_buffer() since atomic uses of miter required it due to use of kmap_atomic(). However, as commit 8290e2d2dcbf ("scatterlist: atomic sg_mapping_iter() no longer needs disabled IRQs") acknowledges disabling interrupts is no longer needed for calls to kmap_atomic() and therefore unneeded for miter ops either, so remove it from sg_copy_buffer(). Link: http://lkml.kernel.org/r/1486040150-14109-3-git-send-email-gilad@benyossef.com Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: <ofir.drang@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-27scatterlist: reorder compound boolean expressionGilad Ben-Yossef1-1/+1
Test the cheaper boolean expression with no side effects first. Link: http://lkml.kernel.org/r/1486040150-14109-2-git-send-email-gilad@benyossef.com Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: <ofir.drang@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-02-08scatterlist: fix a typo in comment block of sg_miter_stop()Masahiro Yamada1-3/+3
Fix the doubled "started" and tidy up the following sentences. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-17scatterlist: allow limited chaining without ARCH_HAS_SG_CHAINChristoph Hellwig1-4/+0
There are a couple of uses of struct scatterlist that never go to the dma_map_sg() helper and thus don't care about ARCH_HAS_SG_CHAIN which indicates that we can map chained S/G list. The most important one is the crypto code, which currently has to open code a few helpers to always allow chaining. This patch removes a few #ifdef ARCH_HAS_SG_CHAIN statements so that we can switch the crypto code to these common helpers. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-30drivers/scsi/scsi_debug.c: resolve sg buffer const-ness issueDave Gordon1-3/+3
do_device_access() takes a separate parameter to indicate the direction of data transfer, which it used to use to select the appropriate function out of sg_pcopy_{to,from}_buffer(). However these two functions now have So this patch makes it bypass these wrappers and call the underlying function sg_copy_buffer() directly; this has the same calling style as do_device_access() i.e. a separate direction-of-transfer parameter and no pointers-to-const, so skipping the wrappers not only eliminates the warning, it also make the code simpler :) [akpm@linux-foundation.org: fix very broken build] Signed-off-by: Dave Gordon <david.s.gordon@intel.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30lib/scatterlist: mark input buffer parameters as 'const'Dave Gordon1-4/+4
The 'buf' parameter of sg(p)copy_from_buffer() can and should be const-qualified, although because of the shared implementation of _to_buffer() and _from_buffer(), we have to cast this away internally. This means that callers who have a 'const' buffer containing the data to be copied to the sg-list no longer have to cast away the const-ness themselves. It also enables improved coverage by code analysis tools. Signed-off-by: Dave Gordon <david.s.gordon@intel.com> Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-30lib/scatterlist.c: fix kerneldoc for sg_pcopy_{to,from}_buffer()Dave Gordon1-2/+2
The kerneldoc for the functions doesn't match the code; the last two parameters (buflen, skip) have been transposed, which is confusing, especially as they're both integral types and the compiler won't warn about swapping them. These functions and the kerneldoc were introduced in commit: df642cea lib/scatterlist: introduce sg_pcopy_from_buffer() ... Author: Akinobu Mita <akinobu.mita@gmail.com> Date: Mon Jul 8 16:01:54 2013 -0700 The only difference between sg_pcopy_{from,to}_buffer() and sg_copy_{from,to}_buffer() is an additional argument that specifies the number of bytes to skip the SG list before copying. The functions have the extra argument at the end, but the kerneldoc lists it in penultimate position. Signed-off-by: Dave Gordon <david.s.gordon@intel.com> Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-03scatterlist: introduce sg_nents_for_lenTom Lendacky1-0/+32
When performing a dma_map_sg() call, the number of sg entries to map is required. Using sg_nents to retrieve the number of sg entries will return the total number of entries in the sg list up to the entry marked as the end. If there happen to be unused entries in the list, these will still be counted. Some dma_map_sg() implementations will not handle the unused entries correctly (lib/swiotlb.c) and execute a BUG_ON. The sg_nents_for_len() function will traverse the sg list and return the number of entries required to satisfy the supplied length argument. This can then be supplied to the dma_map_sg() call to successfully map the sg. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-10-28lib/scatterlist: fix memory leak with scsi-mqTony Battersby1-3/+3
Fix a memory leak with scsi-mq triggered by commands with large data transfer length. Fixes: c53c6d6a68b1 ("scatterlist: allow chaining to preallocated chunks") Cc: <stable@vger.kernel.org> # 3.17.x Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-08-08lib/scatterlist: make ARCH_HAS_SG_CHAIN an actual KconfigLaura Abbott1-2/+2
Rather than have architectures #define ARCH_HAS_SG_CHAIN in an architecture specific scatterlist.h, make it a proper Kconfig option and use that instead. At same time, remove the header files are are now mostly useless and just include asm-generic/scatterlist.h. [sfr@canb.auug.org.au: powerpc files now need asm/dma.h] Signed-off-by: Laura Abbott <lauraa@codeaurora.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> [x86] Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [powerpc] Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Russell King <linux@arm.linux.org.uk> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: 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>
2014-07-25scatterlist: allow chaining to preallocated chunksChristoph Hellwig1-8/+17
Blk-mq drivers usually preallocate their S/G list as part of the request, but if we want to support the very large S/G lists currently supported by the SCSI code that would tie up a lot of memory in the preallocated request pool. Add support to the scatterlist code so that it can initialize a S/G list that uses a preallocated first chunks and dynamically allocated additional chunks. That way the scsi-mq code can preallocate a first page worth of S/G entries as part of the request, and dynamically extend the S/G list when needed. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Webb Scales <webbnh@hp.com> Acked-by: Jens Axboe <axboe@kernel.dk> Tested-by: Bart Van Assche <bvanassche@acm.org> Tested-by: Robert Elliott <elliott@hp.com>
2013-12-08lib/scatterlist: export sg_miter_skip()Ming Lei1-1/+2
sg_copy_buffer() can't meet demand for some drrivers(such usb mass storage), so we have to use the sg_miter_* APIs to access sg buffer, then need export sg_miter_skip() for these drivers. The API is needed for converting to sg_miter_* APIs in USB storage driver for accessing sg buffer. Acked-by: Andrew Morton <akpm@linux-foundation.org> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-31lib/scatterlist.c: don't flush_kernel_dcache_page on slab pageMing Lei1-1/+2
Commit b1adaf65ba03 ("[SCSI] block: add sg buffer copy helper functions") introduces two sg buffer copy helpers, and calls flush_kernel_dcache_page() on pages in SG list after these pages are written to. Unfortunately, the commit may introduce a potential bug: - Before sending some SCSI commands, kmalloc() buffer may be passed to block layper, so flush_kernel_dcache_page() can see a slab page finally - According to cachetlb.txt, flush_kernel_dcache_page() is only called on "a user page", which surely can't be a slab page. - ARCH's implementation of flush_kernel_dcache_page() may use page mapping information to do optimization so page_mapping() will see the slab page, then VM_BUG_ON() is triggered. Aaro Koskinen reported the bug on ARM/kirkwood when DEBUG_VM is enabled, and this patch fixes the bug by adding test of '!PageSlab(miter->page)' before calling flush_kernel_dcache_page(). Signed-off-by: Ming Lei <ming.lei@canonical.com> Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi> Tested-by: Simon Baatz <gmbnomis@gmail.com> Cc: Russell King - ARM Linux <linux@arm.linux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Cc: Aaro Koskinen <aaro.koskinen@iki.fi> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Tejun Heo <tj@kernel.org> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: <stable@vger.kernel.org> [3.2+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09lib/scatterlist: error handling in __sg_alloc_table()Dan Carpenter1-2/+4
I was reviewing code which I suspected might allocate a zero size SG table. That will cause memory corruption. Also we can't return before doing the memset or we could end up using uninitialized memory in the cleanup path. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Akinobu Mita <akinobu.mita@gmail.com> Cc: Imre Deak <imre.deak@intel.com> Cc: Tejun Heo <tj@kernel.org> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Maxim Levitsky <maximlevitsky@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09lib/scatterlist: introduce sg_pcopy_from_buffer() and sg_pcopy_to_buffer()Akinobu Mita1-5/+83
The only difference between sg_pcopy_{from,to}_buffer() and sg_copy_{from,to}_buffer() is an additional argument that specifies the number of bytes to skip the SG list before copying. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Douglas Gilbert <dgilbert@interlog.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Horia Geanta <horia.geanta@freescale.com> Cc: Imre Deak <imre.deak@intel.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09lib/scatterlist: factor out sg_miter_get_next_page() from sg_miter_next()Akinobu Mita1-15/+24
This patchset introduces sg_pcopy_from_buffer() and sg_pcopy_to_buffer(), which copy data between a linear buffer and an SG list. The only difference between sg_pcopy_{from,to}_buffer() and sg_copy_{from,to}_buffer() is an additional argument that specifies the number of bytes to skip the SG list before copying. The main reason for introducing these functions is to fix a problem in scsi_debug module. And there is a local function in crypto/talitos module, which can be replaced by sg_pcopy_to_buffer(). This patch: sg_miter_get_next_page() is used to proceed page iterator to the next page if necessary, and will be used to implement the variants of sg_copy_{from,to}_buffer() later. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: Imre Deak <imre.deak@intel.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "David S. Miller" <davem@davemloft.net> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Douglas Gilbert <dgilbert@interlog.com> Cc: Horia Geanta <horia.geanta@freescale.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-03-27lib/scatterlist: sg_page_iter: support sg lists w/o backing pagesImre Deak1-3/+1
The i915 driver uses sg lists for memory without backing 'struct page' pages, similarly to other IO memory regions, setting only the DMA address for these. It does this, so that it can program the HW MMU tables in a uniform way both for sg lists with and without backing pages. Without a valid page pointer we can't call nth_page to get the current page in __sg_page_iter_next, so add a helper that relevant users can call separately. Also add a helper to get the DMA address of the current page (idea from Daniel). Convert all places in i915, to use the new API. Signed-off-by: Imre Deak <imre.deak@intel.com> Reviewed-by: Damien Lespiau <damien.lespiau@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-02-27lib/scatterlist: use page iterator in the mapping iteratorImre Deak1-25/+23
For better code reuse use the newly added page iterator to iterate through the pages. The offset, length within the page is still calculated by the mapping iterator as well as the actual mapping. Idea from Tejun Heo. Signed-off-by: Imre Deak <imre.deak@intel.com> Cc: Maxim Levitsky <maximlevitsky@gmail.com> Cc: Tejun Heo <tj@kernel.org> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: James Hogan <james.hogan@imgtec.com> Cc: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27lib/scatterlist: add simple page iteratorImre Deak1-0/+38
Add an iterator to walk through a scatter list a page at a time starting at a specific page offset. As opposed to the mapping iterator this is meant to be small, performing well even in simple loops like collecting all pages on the scatterlist into an array or setting up an iommu table based on the pages' DMA address. Signed-off-by: Imre Deak <imre.deak@intel.com> Cc: Maxim Levitsky <maximlevitsky@gmail.com> Cc: Tejun Heo <tj@kernel.org> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Tested-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17scatterlist: don't BUG when we can trivially return a proper error.Nick Bowler1-1/+2
There is absolutely no reason to crash the kernel when we have a perfectly good return value already available to use for conveying failure status. Let's return an error code instead of crashing the kernel: that sounds like a much better plan. [akpm@linux-foundation.org: s/E2BIG/EINVAL/] Signed-off-by: Nick Bowler <nbowler@elliptictech.com> Cc: Maxim Levitsky <maximlevitsky@gmail.com> Cc: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-11Merge branch 'for-3.7/core' of git://git.kernel.dk/linux-blockLinus Torvalds1-0/+19
Pull block IO update from Jens Axboe: "Core block IO bits for 3.7. Not a huge round this time, it contains: - First series from Kent cleaning up and generalizing bio allocation and freeing. - WRITE_SAME support from Martin. - Mikulas patches to prevent O_DIRECT crashes when someone changes the block size of a device. - Make bio_split() work on data-less bio's (like trim/discards). - A few other minor fixups." Fixed up silent semantic mis-merge as per Mikulas Patocka and Andrew Morton. It is due to the VM no longer using a prio-tree (see commit 6b2dbba8b6ac: "mm: replace vma prio_tree with an interval tree"). So make set_blocksize() use mapping_mapped() instead of open-coding the internal VM knowledge that has changed. * 'for-3.7/core' of git://git.kernel.dk/linux-block: (26 commits) block: makes bio_split support bio without data scatterlist: refactor the sg_nents scatterlist: add sg_nents fs: fix include/percpu-rwsem.h export error percpu-rw-semaphore: fix documentation typos fs/block_dev.c:1644:5: sparse: symbol 'blkdev_mmap' was not declared blockdev: turn a rw semaphore into a percpu rw semaphore Fix a crash when block device is read and block size is changed at the same time block: fix request_queue->flags initialization block: lift the initial queue bypass mode on blk_register_queue() instead of blk_init_allocated_queue() block: ioctl to zero block ranges block: Make blkdev_issue_zeroout use WRITE SAME block: Implement support for WRITE SAME block: Consolidate command flag and queue limit checks for merges block: Clean up special command handling logic block/blk-tag.c: Remove useless kfree block: remove the duplicated setting for congestion_threshold block: reject invalid queue attribute values block: Add bio_clone_bioset(), bio_clone_kmalloc() block: Consolidate bio_alloc_bioset(), bio_kmalloc() ...
2012-10-06scatterlist: atomic sg_mapping_iter() no longer needs disabled IRQsTejun Heo1-8/+8
SG mapping iterator w/ SG_MITER_ATOMIC set required IRQ disabled because it originally used KM_BIO_SRC_IRQ to allow use from IRQ handlers. kmap_atomic() has long been updated to handle stacking atomic mapping requests on per-cpu basis and only requires not sleeping while mapped. Update sg_mapping_iter such that atomic iterators only require disabling preemption instead of disabling IRQ. While at it, convert wte weird @ARG@ notations to @ARG in the comment of sg_miter_start(). Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Maxim Levitsky <maximlevitsky@gmail.com> Cc: Alex Dubov <oakad@yahoo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-28scatterlist: refactor the sg_nentsMaxim Levitsky1-5/+2
Replace 'while' with 'for' as suggested by Tejun Heo Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-09-27scatterlist: add sg_nentsMaxim Levitsky1-0/+22
Useful helper to know the number of entries in scatterlist. Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com> Cc: Alex Dubov <oakad@yahoo.com> Acked-by: Tejun Heo <tj@kernel.org> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Jens Axboe <axboe@kernel.dk>