1. 08 Feb, 2016 1 commit
  2. 17 Aug, 2015 1 commit
    • Christoph Hellwig's avatar
      scatterlist: allow limited chaining without ARCH_HAS_SG_CHAIN · 10c95ed9
      Christoph Hellwig authored
      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: default avatarChristoph Hellwig <hch@lst.de>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
  3. 01 Jul, 2015 3 commits
  4. 03 Jun, 2015 1 commit
    • Tom Lendacky's avatar
      scatterlist: introduce sg_nents_for_len · cfaed10d
      Tom Lendacky authored
      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
      Signed-off-by: default avatarTom Lendacky <thomas.lendacky@amd.com>
      Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
  5. 28 Oct, 2014 2 commits
  6. 08 Aug, 2014 1 commit
  7. 25 Jul, 2014 1 commit
  8. 09 Dec, 2013 1 commit
  9. 31 Oct, 2013 1 commit
    • Ming Lei's avatar
      lib/scatterlist.c: don't flush_kernel_dcache_page on slab page · 3d77b50c
      Ming Lei authored
      Commit b1adaf65 ("[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
       - 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: default avatarMing Lei <ming.lei@canonical.com>
      Reported-by: default avatarAaro Koskinen <aaro.koskinen@iki.fi>
      Tested-by: default avatarSimon 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: default avatarCatalin 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: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
  10. 09 Jul, 2013 3 commits
  11. 27 Mar, 2013 1 commit
  12. 28 Feb, 2013 2 commits
  13. 18 Dec, 2012 1 commit
  14. 05 Oct, 2012 1 commit
  15. 28 Sep, 2012 1 commit
  16. 27 Sep, 2012 1 commit
  17. 31 Jul, 2012 1 commit
    • Mandeep Singh Baines's avatar
      lib/scatterlist: do not re-write gfp_flags in __sg_alloc_table() · e04f2283
      Mandeep Singh Baines authored
      We are seeing a lot of sg_alloc_table allocation failures using the new
      drm prime infrastructure.  We isolated the cause to code in
      __sg_alloc_table that was re-writing the gfp_flags.
      There is a comment in the code that suggest that there is an assumption
      about the allocation coming from a memory pool.  This was likely true
      when sg lists were primarily used for disk I/O.
      Signed-off-by: default avatarMandeep Singh Baines <msb@chromium.org>
      Cc: Jens Axboe <axboe@kernel.dk>
      Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Cong Wang <amwang@redhat.com>
      Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
      Cc: Rob Clark <rob.clark@linaro.org>
      Cc: Sumit Semwal <sumit.semwal@linaro.org>
      Cc: Inki Dae <inki.dae@samsung.com>
      Cc: Dave Airlie <airlied@redhat.com>
      Cc: Sonny Rao <sonnyrao@chromium.org>
      Cc: Olof Johansson <olofj@chromium.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
  18. 30 Jul, 2012 1 commit
  19. 20 Mar, 2012 1 commit
  20. 07 Mar, 2012 1 commit
  21. 30 Aug, 2010 1 commit
  22. 28 Jul, 2010 1 commit
    • Chris Wilson's avatar
      lib/scatterlist: Hook sg_kmalloc into kmemleak (v2) · b94de9bb
      Chris Wilson authored
      kmemleak ignores page_alloc() and so believes the final sub-page
      allocation using the plain kmalloc is decoupled and lost. This leads to
      lots of false-positives with code that uses scatterlists.
      The options seem to be either to tell kmemleak that the kmalloc is not
      leaked or to notify kmemleak of the page allocations. The danger of the
      first approach is that we may hide a real leak, so choose the latter
      approach (of which I am not sure of the downsides).
      v2: Added comments on the suggestion of Catalin.
      Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
      Cc: Tejun Heo <tj@kernel.org>
      Cc: Jens Axboe <jaxboe@fusionio.com>
      Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
  23. 30 Mar, 2010 1 commit
    • Tejun Heo's avatar
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      Tejun Heo authored
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking 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.
      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
      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
      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
      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: default avatarTejun Heo <tj@kernel.org>
      Guess-its-ok-by: default avatarChristoph Lameter <cl@linux-foundation.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
  24. 31 Jul, 2009 1 commit
  25. 22 Apr, 2009 1 commit
  26. 20 Nov, 2008 1 commit
  27. 11 Sep, 2008 1 commit
  28. 23 Jul, 2008 1 commit
    • Tejun Heo's avatar
      sg: reimplement sg mapping iterator · 137d3edb
      Tejun Heo authored
      This is alternative implementation of sg content iterator introduced
      by commit 83e7d317... from Pierre Ossman in next-20080716.  As there's
      already an sg iterator which iterates over sg entries themselves, name
      this sg_mapping_iterator.
      Slightly edited description from the original implementation follows.
      Iteration over a sg list is not that trivial when you take into
      account that memory pages might have to be mapped before being used.
      Unfortunately, that means that some parts of the kernel restrict
      themselves to directly accesible memory just to not have to deal with
      the mess.
      This patch adds a simple iterator system that allows any code to
      easily traverse an sg list and not have to deal with all the details.
      The user can decide to consume part of the iteration.  Also, iteration
      can be stopped and resumed later if releasing the kmap between
      iteration steps is necessary.  These features are useful to implement
      piecemeal sg copying for interrupt drive PIO for example.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarPierre Ossman <drzeus@drzeus.cx>
  29. 07 Apr, 2008 1 commit
  30. 28 Jan, 2008 2 commits