1. 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.
      
        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: 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>
      5a0e3ad6
  2. 03 Dec, 2009 1 commit
    • Martin K. Petersen's avatar
      block: Allow devices to indicate whether discarded blocks are zeroed · 98262f27
      Martin K. Petersen authored
      The discard ioctl is used by mkfs utilities to clear a block device
      prior to putting metadata down.  However, not all devices return zeroed
      blocks after a discard.  Some drives return stale data, potentially
      containing old superblocks.  It is therefore important to know whether
      discarded blocks are properly zeroed.
      
      Both ATA and SCSI drives have configuration bits that indicate whether
      zeroes are returned after a discard operation.  Implement a block level
      interface that allows this information to be bubbled up the stack and
      queried via a new block device ioctl.
      Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      98262f27
  3. 03 Oct, 2009 1 commit
  4. 22 May, 2009 2 commits
  5. 16 Apr, 2009 1 commit
  6. 29 Dec, 2008 1 commit
  7. 04 Dec, 2008 2 commits
  8. 23 Oct, 2008 1 commit
  9. 21 Oct, 2008 5 commits
  10. 09 Oct, 2008 1 commit
  11. 13 May, 2008 1 commit
  12. 17 Apr, 2008 1 commit
    • Bartlomiej Zolnierkiewicz's avatar
      ide: remove broken/dangerous HDIO_[UNREGISTER,SCAN]_HWIF ioctls (take 3) · 93de00fd
      Bartlomiej Zolnierkiewicz authored
      hdparm explicitely marks HDIO_[UNREGISTER,SCAN]_HWIF ioctls as DANGEROUS
      and given the number of bugs we can assume that there are no real users:
      
      * DMA has no chance of working because DMA resources are released by
        ide_unregister() and they are never allocated again.
      
      * Since ide_init_hwif_ports() is used for ->io_ports[] setup the ioctls
        don't work for almost all hosts with "non-standard" (== non ISA-like)
        layout of IDE taskfile registers (there is a lot of such host drivers).
      
      * ide_port_init_devices() is not called when probing IDE devices so:
        - drive->autotune is never set and IDE host/devices are not programmed
          for the correct PIO/DMA transfer modes (=> possible data corruption)
        - host specific I/O 32-bit and IRQ unmasking settings are not applied
          (=> possible data corruption)
        - host specific ->port_init_devs method is not called (=> no luck with
          ht6560b, qd65xx and opti621 host drivers)
      
      * ->rw_disk method is not preserved (=> no HPT3xxN chipsets support).
      
      * ->serialized flag is not preserved (=> possible data corruption when
         using icside, aec62xx (ATP850UF chipset), cmd640, cs5530, hpt366
         (HPT3xxN chipsets), rz1000, sc1200, dtc2278 and ht6560b host drivers).
      
      * ->ack_intr method is not preserved (=> needed by ide-cris, buddha,
        gayle and macide host drivers).
      
      * ->sata_scr[] and sata_misc[] is cleared by ide_unregister() and it
        isn't initialized again (SiI3112 support needs them).
      
      * To issue an ioctl() there need to be at least one IDE device present
        in the system.
      
      * ->cable_detect method is not preserved + it is not called when probing
        IDE devices so cable detection is broken (however since DMA support is
        also broken it doesn't really matter ;-).
      
      * Some objects which may have already been freed in ide_unregister()
        are restored by ide_hwif_restore() (i.e. ->hwgroup).
      
      * ide_register_hw() may unregister unrelated IDE ports if free ide_hwifs[]
        slot cannot be found.
      
      * When IDE host drivers are modular unregistered port may be re-used by
        different host driver that owned it first causing subtle bugs.
      
      Since we now have a proper warm-plug support remove these ioctls,
      then remove no longer needed:
      - ide_register_hw() and ide_hwif_restore() functions
      - 'init_default' and 'restore' arguments of ide_unregister()
      - zeroeing of hwif->{dma,extra}_* fields in ide_unregister()
      
      As an added bonus IDE core code size shrinks by ~3kB (x86-32).
      
      v2:
      * fix ide_unregister() arguments in cleanup_module() (Andrew Morton).
      
      v3:
      * fix ide_unregister() arguments in palm_bk3710.c.
      Acked-by: default avatarSergei Shtylyov <sshtylyov@ru.mvista.com>
      Signed-off-by: default avatarBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
      93de00fd
  13. 28 Jan, 2008 1 commit
  14. 29 Oct, 2007 1 commit
  15. 10 Oct, 2007 7 commits