1. 01 3月, 2013 1 次提交
  2. 21 9月, 2012 1 次提交
    • A
      xen/gndev: Xen backend support for paged out grant targets V4. · c571898f
      Andres Lagar-Cavilla 提交于
      Since Xen-4.2, hvm domains may have portions of their memory paged out. When a
      foreign domain (such as dom0) attempts to map these frames, the map will
      initially fail. The hypervisor returns a suitable errno, and kicks an
      asynchronous page-in operation carried out by a helper. The foreign domain is
      expected to retry the mapping operation until it eventually succeeds. The
      foreign domain is not put to sleep because itself could be the one running the
      pager assist (typical scenario for dom0).
      
      This patch adds support for this mechanism for backend drivers using grant
      mapping and copying operations. Specifically, this covers the blkback and
      gntdev drivers (which map foreign grants), and the netback driver (which copies
      foreign grants).
      
      * Add a retry method for grants that fail with GNTST_eagain (i.e. because the
        target foreign frame is paged out).
      * Insert hooks with appropriate wrappers in the aforementioned drivers.
      
      The retry loop is only invoked if the grant operation status is GNTST_eagain.
      It guarantees to leave a new status code different from GNTST_eagain. Any other
      status code results in identical code execution as before.
      
      The retry loop performs 256 attempts with increasing time intervals through a
      32 second period. It uses msleep to yield while waiting for the next retry.
      
      V2 after feedback from David Vrabel:
      * Explicit MAX_DELAY instead of wrap-around delay into zero
      * Abstract GNTST_eagain check into core grant table code for netback module.
      
      V3 after feedback from Ian Campbell:
      * Add placeholder in array of grant table error descriptions for unrelated
        error code we jump over.
      * Eliminate single map and retry macro in favor of a generic batch flavor.
      * Some renaming.
      * Bury most implementation in grant_table.c, cleaner interface.
      
      V4 rebased on top of sync of Xen grant table interface headers.
      Signed-off-by: NAndres Lagar-Cavilla <andres@lagarcavilla.org>
      Acked-by: NIan Campbell <ian.campbell@citrix.com>
      [v5: Fixed whitespace issues]
      Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      c571898f
  3. 27 2月, 2012 1 次提交
  4. 21 12月, 2011 2 次提交
  5. 17 11月, 2011 1 次提交
  6. 01 11月, 2011 1 次提交
  7. 30 9月, 2011 1 次提交
  8. 18 10月, 2010 1 次提交
  9. 08 8月, 2010 1 次提交
    • D
      xenbus: Make xenbus_switch_state transactional · 5b61cb90
      Daniel Stodden 提交于
      According to the comments, this was how it's been done years ago, but
      apparently took an xbt pointer from elsewhere back then. The code was
      removed because of consistency issues: cancellation wont't roll back
      the saved xbdev->state.
      
      Still, unsolicited writes to the state field remain an issue,
      especially if device shutdown takes thread synchronization, and subtle
      races cause accidental recreation of the device node.
      
      Fixed by reintroducing the transaction. An internal one is sufficient,
      so the xbdev->state value remains consistent.
      
      Also fixes the original hack to prevent infinite recursion. Instead of
      bailing out on the first attempt to switch to Closing, checks call
      depth now.
      Signed-off-by: NDaniel Stodden <daniel.stodden@citrix.com>
      Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      5b61cb90
  10. 30 3月, 2010 1 次提交
    • T
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      Tejun Heo 提交于
      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: NTejun Heo <tj@kernel.org>
      Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  11. 09 1月, 2009 1 次提交
  12. 03 7月, 2008 1 次提交
  13. 25 4月, 2008 1 次提交
    • I
      xen: replace callers of alloc_vm_area()/free_vm_area() with xen_ prefixed one · 5f0ababb
      Isaku Yamahata 提交于
      Don't use alloc_vm_area()/free_vm_area() directly, instead define
      xen_alloc_vm_area()/xen_free_vm_area() and use them.
      
      alloc_vm_area()/free_vm_area() are used to allocate/free area which
      are for grant table mapping. Xen/x86 grant table is based on virtual
      address so that alloc_vm_area()/free_vm_area() are suitable.
      On the other hand Xen/ia64 (and Xen/powerpc) grant table is based on
      pseudo physical address (guest physical address) so that allocation
      should be done differently.
      The original version of xenified Linux/IA64 have its own
      allocate_vm_area()/free_vm_area() definitions which don't allocate vm area
      contradictory to those names.
      Now vanilla Linux already has its definitions so that it's impossible
      to have IA64 definitions of allocate_vm_area()/free_vm_area().
      Instead introduce xen_allocate_vm_area()/xen_free_vm_area() and use them.
      Signed-off-by: NIsaku Yamahata <yamahata@valinux.co.jp>
      Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
      Signed-off-by: NIngo Molnar <mingo@elte.hu>
      Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      5f0ababb
  14. 18 7月, 2007 1 次提交