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  1. 12 9月, 2011 6 次提交
    • M
      block: Clean up remaining users of "removable" · 2c6942fa
      由 Markus Armbruster 提交于 
      BlockDriverState member removable is a confused mess.  It is true when
an ide-cd, scsi-cd or floppy qdev is attached, or when the
BlockDriverState was created with -drive if={floppy,sd} or -drive
if={ide,scsi,xen,none},media=cdrom ("created removable"), except when
an ide-hd, scsi-hd, scsi-generic or virtio-blk qdev is attached.

Three users remain:

1. eject_device(), via bdrv_is_removable() uses it to determine
   whether a block device can eject media.

2. bdrv_info() is monitor command "info block".  QMP documentation
   says "true if the device is removable, false otherwise".  From the
   monitor user's point of view, the only sensible interpretation of
   "is removable" is "can eject media with monitor commands eject and
   change".

A block device can eject media unless a device is attached that
doesn't support it.  Switch the two users over to new
bdrv_dev_has_removable_media() that returns exactly that.

3. bdrv_getlength() uses to suppress its length cache when media can
   change (see commit 46a4e4e6).  Media change is either monitor
   command change (updates the length cache), monitor command eject
   (doesn't update the length cache, easily fixable), or physical
   media change (invalidates length cache, not so easily fixable).

I'm refraining from improving anything here, because this series is
long enough already.  Instead, I simply switch it over to
bdrv_dev_has_removable_media() as well.

This changes the behavior of the length cache and of monitor commands
eject and change in two cases:

a. drive not created removable, no device attached

   The commit makes the drive removable, and defeats the length cache.

   Example: -drive if=none

b. drive created removable, but the attached drive is non-removable,
   and doesn't call bdrv_set_removable(..., 0) (most devices don't)

   The commit makes the drive non-removable, and enables the length
   cache.

   Example: -drive if=xen,media=cdrom -M xenpv

   The other non-removable devices that don't call
   bdrv_set_removable() can't currently use a drive created removable,
   either because they aren't qdevified, or because they lack a drive
   property.  Won't stay that way.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      2c6942fa
    • M
      block: Rename bdrv_set_locked() to bdrv_lock_medium() · 025e849a
      由 Markus Armbruster 提交于 
      While there, make the locked parameter bool.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      025e849a
    • M
      block: Drop medium lock tracking, ask device models instead · f107639a
      由 Markus Armbruster 提交于 
      Requires new BlockDevOps member is_medium_locked().  Implement for IDE
and SCSI CD-ROMs.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      f107639a
    • M
      block: Leave enforcing tray lock to device models · fdec4404
      由 Markus Armbruster 提交于 
      The device model knows best when to accept the guest's eject command.
No need to detour through the block layer.

bdrv_eject() can't fail anymore.  Make it void.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      fdec4404
    • M
      block: Drop tray status tracking, no longer used · 22cf56c4
      由 Markus Armbruster 提交于 
      Commit 4be9762a is now completely redone.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      22cf56c4
    • M
      block: Revert entanglement of bdrv_is_inserted() with tray status · a1aff5bf
      由 Markus Armbruster 提交于 
      Commit 4be9762a changed bdrv_is_inserted() to fail when the tray is
open.  Unfortunately, there are two different kinds of users, with
conflicting needs.

1. Device models using bdrv_eject(), currently ide-cd and scsi-cd.
They expect bdrv_is_inserted() to reflect the tray status.  Commit
4be9762a makes them happy.

2. Code that wants to know whether a BlockDriverState has media, such
as find_image_format(), bdrv_flush_all().  Commit 4be9762a makes them
unhappy.  In particular, it breaks flush on VM stop for media ejected
by the guest.

Revert the change to bdrv_is_inserted().  Check the tray status in the
device models instead.

Note on IDE: Since only ATAPI devices have a tray, and they don't
accept ATA commands since the recent commit "ide: Reject ATA commands
specific to drive kinds", checking in atapi.c suffices.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      a1aff5bf
  3. 06 9月, 2011 6 次提交
  5. 03 9月, 2011 1 次提交
    • S
      Use new macro QEMU_PACKED for packed structures · 541dc0d4
      由 Stefan Weil 提交于 
      Most changes were made using these commands:

git grep -la '__attribute__((packed))'|xargs perl -pi -e 's/__attribute__\(\(packed\)\)/QEMU_PACKED/'
git grep -la '__attribute__ ((packed))'|xargs perl -pi -e 's/__attribute__ \(\(packed\)\)/QEMU_PACKED/'
git grep -la '__attribute__((__packed__))'|xargs perl -pi -e 's/__attribute__\(\(__packed__\)\)/QEMU_PACKED/'
git grep -la '__attribute__ ((__packed__))'|xargs perl -pi -e 's/__attribute__ \(\(__packed__\)\)/QEMU_PACKED/'
git grep -la '__attribute((packed))'|xargs perl -pi -e 's/__attribute\(\(packed\)\)/QEMU_PACKED/'

Whitespace in linux-user/syscall_defs.h was fixed manually
to avoid warnings from scripts/checkpatch.pl.

Manual changes were also applied to hw/pc.c.

I did not fix indentation with tabs in block/vvfat.c.
The patch will show 4 errors with scripts/checkpatch.pl.
Signed-off-by: NStefan Weil <weil@mail.berlios.de>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>
      541dc0d4
  7. 27 8月, 2011 1 次提交
  9. 26 8月, 2011 1 次提交
    • C
      block: explicit I/O accounting · a597e79c
      由 Christoph Hellwig 提交于 
      Decouple the I/O accounting from bdrv_aio_readv/writev/flush and
make the hardware models call directly into the accounting helpers.

This means:
 - we do not count internal requests from image formats in addition
   to guest originating I/O
 - we do not double count I/O ops if the device model handles it
   chunk wise
 - we only account I/O once it actuall is done
 - can extent I/O accounting to synchronous or coroutine I/O easily
 - implement I/O latency tracking easily (see the next patch)

I've conveted the existing device model callers to the new model,
device models that are using synchronous I/O and weren't accounted
before haven't been updated yet.  Also scsi hasn't been converted
to the end-to-end accounting as I want to defer that after the pending
scsi layer overhaul.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      a597e79c
  11. 23 8月, 2011 3 次提交
  13. 22 8月, 2011 1 次提交
  15. 21 8月, 2011 1 次提交
  17. 04 8月, 2011 1 次提交
  19. 02 8月, 2011 4 次提交
    • K
      async: Remove AsyncContext · 384acbf4
      由 Kevin Wolf 提交于 
      The purpose of AsyncContexts was to protect qcow and qcow2 against reentrancy
during an emulated bdrv_read/write (which includes a qemu_aio_wait() call and
can run AIO callbacks of different requests if it weren't for AsyncContexts).

Now both qcow and qcow2 are protected by CoMutexes and AsyncContexts can be
removed.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      384acbf4
    • K
      block: Add bdrv_co_readv/writev emulation · f9f05dc5
      由 Kevin Wolf 提交于 
      In order to be able to call bdrv_co_readv/writev for drivers that don't
implement the functions natively, add an emulation that uses the AIO functions
to implement them.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      f9f05dc5
    • K
      block: Emulate AIO functions with bdrv_co_readv/writev · 68485420
      由 Kevin Wolf 提交于 
      Use the bdrv_co_readv/writev callbacks to implement bdrv_aio_readv/writev and
bdrv_read/write if a driver provides the coroutine version instead of the
synchronous or AIO version.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      68485420
    • K
      block: Add bdrv_co_readv/writev · da1fa91d
      由 Kevin Wolf 提交于 
      Add new block driver callbacks bdrv_co_readv/writev, which work on a
QEMUIOVector like bdrv_aio_*, but don't need a callback. The function may only
be called inside a coroutine, so a block driver implementing this interface can
yield instead of blocking during I/O.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      da1fa91d
  21. 01 8月, 2011 4 次提交
  23. 19 7月, 2011 1 次提交
  25. 08 6月, 2011 2 次提交
  27. 19 5月, 2011 2 次提交
    • M
      block: Remove type hint, it's guest matter, doesn't belong here · 8d278467
      由 Markus Armbruster 提交于 
      No users of bdrv_get_type_hint() left.  bdrv_set_type_hint() can make
the media removable by side effect.  Make that explicit.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      8d278467
    • M
      block QMP: Deprecate query-block's "type", drop info block's "type=" · d8aeeb31
      由 Markus Armbruster 提交于 
      query-block's specification documents response member "type" with
values "hd", "cdrom", "floppy", "unknown".

Its value is unreliable: a block device used as floppy has type
"floppy" if created with if=floppy, but type "hd" if created with
if=none.

That's because with if=none, the type is at best a declaration of
intent: the drive can be connected to any guest device.  Its type is
really the guest device's business.  Reporting it here is wrong.

No known user of QMP uses "type".  It's unlikely that any unknown
users exist, because its value is useless unless you know how the
block device was created.  But then you also know the true value.

Fixing the broken value risks breaking (hypothetical!) clients that
somehow rely on the current behavior.  Not fixing the value risks
breaking (hypothetical!) clients that rely on the value to be
accurate.  Can't entirely avoid hypothetical lossage.  Change the
value to be always "unknown".

This makes "info block" always report "type=unknown".  Pointless.
Change it to not report the type.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      d8aeeb31
  29. 08 5月, 2011 1 次提交
  31. 06 5月, 2011 1 次提交
  33. 07 4月, 2011 3 次提交
    • S
      block: Do not cache device size for removable media · 46a4e4e6
      由 Stefan Hajnoczi 提交于 
      The block layer caches the device size to avoid doing lseek(fd, 0,
SEEK_END) every time this value is needed.  For removable media the
device size becomes stale if a new medium is inserted.  This patch
simply prevents device size caching for removable media.

A smarter solution is to update the cached device size when a new medium
is inserted.  Given that there are currently bugs with CD-ROM media
change I do not want to implement that approach until we've gotten
things correct first.
Signed-off-by: NStefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      46a4e4e6
    • S
      trace: Trace bdrv_set_locked() · b8c6d095
      由 Stefan Hajnoczi 提交于 
      It can be handy to know when the guest locks/unlocks the CD-ROM tray.
This trace event makes that possible.
Signed-off-by: NStefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      b8c6d095
    • R
      Do not delete BlockDriverState when deleting the drive · d22b2f41
      由 Ryan Harper 提交于 
      When removing a drive from the host-side via drive_del we currently have
the following path:

drive_del
qemu_aio_flush()
bdrv_close()    // zaps bs->drv, which makes any subsequent I/O get
                // dropped.  Works as designed
drive_uninit()
bdrv_delete()   // frees the bs.  Since the device is still connected to
                // bs, any subsequent I/O is a use-after-free.

The value of bs->drv becomes unpredictable on free.  As long as it
remains null, I/O still gets dropped, however it could become non-null
at any point after the free resulting SEGVs or other QEMU state
corruption.

To resolve this issue as simply as possible, we can chose to not
actually delete the BlockDriverState pointer.  Since bdrv_close()
handles setting the drv pointer to NULL, we just need to remove the
BlockDriverState from the QLIST that is used to enumerate the block
devices.  This is currently handled within bdrv_delete, so move this
into its own function, bdrv_make_anon().

The result is that we can now invoke drive_del, this closes the file
descriptors and sets BlockDriverState->drv to NULL which prevents futher
IO to the device, and since we do not free BlockDriverState, we don't
have to worry about the copy retained in the block devices.

We also don't attempt to remove the qdev property since we are no longer
deleting the BlockDriverState on drives with associated drives.  This
also allows for removing Drives with no devices associated either.
Reported-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NRyan Harper <ryanh@us.ibm.com>
Acked-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      d22b2f41
  35. 15 3月, 2011 1 次提交