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  1. 03 12月, 2009 18 次提交
  3. 09 11月, 2009 2 次提交
  5. 15 10月, 2009 1 次提交
  7. 05 10月, 2009 2 次提交
  9. 11 9月, 2009 1 次提交
    • C
      block: add enable_write_cache flag · e900a7b7
      由 Christoph Hellwig 提交于 
      Add a enable_write_cache flag in the block driver state, and use it to
decide if we claim to have a volatile write cache that needs controlled
flushing from the guest.  The flag is off if cache=writethrough is
defined because O_DSYNC guarantees that every write goes to stable
storage, and it is on for cache=none and cache=writeback.

Both scsi-disk and ide now use the new flage, changing from their
defaults of always off (ide) or always on (scsi-disk).
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
      e900a7b7
  11. 10 9月, 2009 1 次提交
  13. 30 7月, 2009 1 次提交
    • M
      Fix VM state change handlers running out of order · 213189ab
      由 Markus Armbruster 提交于 
      When a VM state change handler changes VM state, other VM state change
handlers can see the state transitions out of order.

bmdma_map(), scsi_disk_init() and virtio_blk_init() install VM state
change handlers to restart DMA.  These handlers can vm_stop() by
running into a write error on a drive with werror=stop.  This throws
the VM state change handler callback into disarray.  Here's an example
case I observed:

0. The virtual IDE drive goes south.  All future writes return errors.

1. Something encounters a write error, and duly stops the VM with
   vm_stop().

2. vm_stop() calls vm_state_notify(0).

3. vm_state_notify() runs the callbacks in list vm_change_state_head.
   It contains ide_dma_restart_cb() installed by bmdma_map().  It also
   contains audio_vm_change_state_handler() installed by audio_init().

4. audio_vm_change_state_handler() stops audio stuff.

5. User continues VM with monitor command "c".  This runs vm_start().

6. vm_start() calls vm_state_notify(1).

7. vm_state_notify() runs the callbacks in vm_change_state_head.

8. ide_dma_restart_cb() happens to come first.  It does its work, runs
   into a write error, and duly stops the VM with vm_stop().

9. vm_stop() runs vm_state_notify(0).

10. vm_state_notify() runs the callbacks in vm_change_state_head.

11. audio_vm_change_state_handler() stops audio stuff.  Which isn't
   running.

12. vm_stop() finishes, ide_dma_restart_cb() finishes, step 7's
   vm_state_notify() resumes running handlers.

13. audio_vm_change_state_handler() starts audio stuff.  Oopsie.

Fix this by moving the actual write from each VM state change handler
into a new bottom half (suggested by Gleb Natapov).
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
      213189ab
  15. 21 7月, 2009 1 次提交
  17. 14 5月, 2009 1 次提交
  19. 14 4月, 2009 1 次提交
  21. 08 4月, 2009 1 次提交
  23. 29 3月, 2009 4 次提交
  25. 30 1月, 2009 1 次提交
  27. 29 1月, 2009 3 次提交
  29. 23 1月, 2009 1 次提交
  31. 15 1月, 2009 1 次提交