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  1. 13 4月, 2016 2 次提交
    • P
      ide: really restart pending and in-flight atapi dma · 502356ee
      由 Pavel Butsykin 提交于 
      Restart of ATAPI DMA used to be unreachable, because the request to do
so wasn't indicated in bus->error_status due to the lack of spare bits, and
ide_restart_bh() would return early doing nothing.

This patch makes use of the observation that not all bit combinations were
possible in ->error_status. In particular, IDE_RETRY_READ only made sense
together with IDE_RETRY_DMA or IDE_RETRY_PIO. This allows to re-use
IDE_RETRY_READ alone as an indicator of ATAPI DMA restart request.

To makes things more uniform, ATAPI DMA gets its own value for ->dma_cmd.
As a means against confusion, macros are added to test the state of
->error_status.

The patch fixes the restart of both in-flight and pending ATAPI DMA,
following the scheme similar to that of IDE DMA.

[Including a fixup patch:
Message-id: 1460465594-15777-1-git-send-email-pbutsykin@virtuozzo.com
--js]
Signed-off-by: NPavel Butsykin <pbutsykin@virtuozzo.com>
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Message-id: 1459924806-306-4-git-send-email-den@openvz.org
Signed-off-by: NJohn Snow <jsnow@redhat.com>
      502356ee
    • P
      ide: don't lose pending dma state · 218fd37c
      由 Pavel Butsykin 提交于 
      If the migration occurs after the IDE DMA has been set up but before it
has been initiated, the state gets lost upon save/restore. Specifically,
->dma_cb callback gets cleared, so, when the guest eventually starts bus
mastering, the DMA never completes, causing the guest to time out the
operation.

OTOH all the infrastructure is already in place to restart the DMA if
the migration happens while the DMA is in progress.

So reuse that infrastructure, by setting bus->error_status based on
->dma_cmd in pre_save if ->dma_cb callback is already set but DMAING is
clear. This will indicate the need for restart and make sure ->dma_cb
is restored in ide_restart_bh(); howeover since DMAING is clear the state
upon restore will be exactly "ready for DMA" as before the save.
Signed-off-by: NPavel Butsykin <pbutsykin@virtuozzo.com>
Reviewed-by: NRoman Kagan <rkagan@virtuozzo.com>
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Message-id: 1459924806-306-2-git-send-email-den@openvz.org
Signed-off-by: NJohn Snow <jsnow@redhat.com>
      218fd37c
  3. 23 3月, 2016 2 次提交
  5. 11 2月, 2016 6 次提交
  7. 29 1月, 2016 1 次提交
    • P
      ide: Clean up includes · 53239262
      由 Peter Maydell 提交于 
      Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1453832250-766-17-git-send-email-peter.maydell@linaro.org
      53239262
  9. 18 11月, 2015 2 次提交
  11. 12 11月, 2015 2 次提交
  13. 04 11月, 2015 1 次提交
  15. 18 9月, 2015 3 次提交
    • J
      atapi: abort transfers with 0 byte limits · 9ef2e93f
      由 John Snow 提交于 
      We're supposed to abort on transfers like this, unless we fill
Word 125 of our IDENTIFY data with a default transfer size, which
we don't currently do.

This is an ATA error, not a SCSI/ATAPI one.
See ATA8-ACS3 sections 7.17.6.49 or 7.21.5.

If we don't do this, QEMU will loop forever trying to transfer
zero bytes, which isn't particularly useful.
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Message-id: 1442253685-23349-2-git-send-email-jsnow@redhat.com
      9ef2e93f
    • J
      ide: fix ATAPI command permissions · d9033e1d
      由 John Snow 提交于 
      We're a little too lenient with what we'll let an ATAPI drive handle.
Clamp down on the IDE command execution table to remove CD_OK permissions
from commands that are not and have never been ATAPI commands.

For ATAPI command validity, please see:
- ATA4 Section 6.5 ("PACKET Command feature set")
- ATA8/ACS Section 4.3 ("The PACKET feature set")
- ACS3 Section 4.3 ("The PACKET feature set")

ACS3 has a historical command validity table in Table B.4
("Historical Command Assignments") that can be referenced to find when
a command was introduced, deprecated, obsoleted, etc.

The only reference for ATAPI command validity is by checking that
version's PACKET feature set section.

ATAPI was introduced by T13 into ATA4, all commands retired prior to ATA4
therefore are assumed to have never been ATAPI commands.

Mandatory commands, as listed in ATA8-ACS3, are:

- DEVICE RESET
- EXECUTE DEVICE DIAGNOSTIC
- IDENTIFY DEVICE
- IDENTIFY PACKET DEVICE
- NOP
- PACKET
- READ SECTOR(S)
- SET FEATURES

Optional commands as listed in ATA8-ACS3, are:

- FLUSH CACHE
- READ LOG DMA EXT
- READ LOG EXT
- WRITE LOG DMA EXT
- WRITE LOG EXT

All other commands are illegal to send to an ATAPI device and should
be rejected by the device.

CD_OK removal justifications:

0x06 WIN_DSM              Defined in ACS2. Not valid for ATAPI.
0x21 WIN_READ_ONCE        Retired in ATA5. Not ATAPI in ATA4.
0x94 WIN_STANDBYNOW2      Retired in ATA4. Did not coexist with ATAPI.
0x95 WIN_IDLEIMMEDIATE2   Retired in ATA4. Did not coexist with ATAPI.
0x96 WIN_STANDBY2         Retired in ATA4. Did not coexist with ATAPI.
0x97 WIN_SETIDLE2         Retired in ATA4. Did not coexist with ATAPI.
0x98 WIN_CHECKPOWERMODE2  Retired in ATA4. Did not coexist with ATAPI.
0x99 WIN_SLEEPNOW2        Retired in ATA4. Did not coexist with ATAPI.
0xE0 WIN_STANDBYNOW1      Not part of ATAPI in ATA4, ACS or ACS3.
0xE1 WIN_IDLEIMMDIATE     Not part of ATAPI in ATA4, ACS or ACS3.
0xE2 WIN_STANDBY          Not part of ATAPI in ATA4, ACS or ACS3.
0xE3 WIN_SETIDLE1         Not part of ATAPI in ATA4, ACS or ACS3.
0xE4 WIN_CHECKPOWERMODE1  Not part of ATAPI in ATA4, ACS or ACS3.
0xE5 WIN_SLEEPNOW1        Not part of ATAPI in ATA4, ACS or ACS3.
0xF8 WIN_READ_NATIVE_MAX  Obsoleted in ACS3. Not ATAPI in ATA4 or ACS.

This patch fixes a divide by zero fault that can be caused by sending
the WIN_READ_NATIVE_MAX command to an ATAPI drive, which causes it to
attempt to use zeroed CHS values to perform sector arithmetic.
Reported-by: NQinghao Tang <luodalongde@gmail.com>
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Message-id: 1441816082-21031-1-git-send-email-jsnow@redhat.com
CC: qemu-stable@nongnu.org
      d9033e1d
    • J
      ide: unify io_buffer_offset increments · aaeda4a3
      由 John Snow 提交于 
      IDEState's io_buffer_offset was originally added to keep track of offsets
in AHCI rather exclusively, but it was added to IDEState instead of an
AHCI-specific structure.

AHCI fakes all PIO transfers using DMA and a scatter-gather list. When
the core or atapi layers invoke HBA-specific mechanisms for transfers,
they do not always know that it is being backed by DMA or a sglist, so
this offset is not always updated by the HBA code everywhere.

If we modify it in dma_buf_commit, however, any HBA that needs to use
this offset to manage operating on only part of a sglist will have
access to it.

This will fix ATAPI PIO transfers performed through the AHCI HBA,
which were previously not modifying this value appropriately.

This will fix ATAPI PIO transfers larger than one sector.
Reported-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Tested-by: NLaszlo Ersek <lersek@redhat.com>
Message-id: 1440546331-29087-2-git-send-email-jsnow@redhat.com
CC: qemu-stable@nongnu.org
      aaeda4a3
  17. 27 7月, 2015 2 次提交
    • K
      ide: Clear DRQ after handling all expected accesses · cb72cba8
      由 Kevin Wolf 提交于 
      This is additional hardening against an end_transfer_func that fails to
clear the DRQ status bit. The bit must be unset as soon as the PIO
transfer has completed, so it's better to do this in a central place
instead of duplicating the code in all commands (and forgetting it in
some).
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
      cb72cba8
    • K
      ide: Check array bounds before writing to io_buffer (CVE-2015-5154) · d2ff8585
      由 Kevin Wolf 提交于 
      If the end_transfer_func of a command is called because enough data has
been read or written for the current PIO transfer, and it fails to
correctly call the command completion functions, the DRQ bit in the
status register and s->end_transfer_func may remain set. This allows the
guest to access further bytes in s->io_buffer beyond s->data_end, and
eventually overflowing the io_buffer.

One case where this currently happens is emulation of the ATAPI command
START STOP UNIT.

This patch fixes the problem by adding explicit array bounds checks
before accessing the buffer instead of relying on end_transfer_func to
function correctly.

Cc: qemu-stable@nongnu.org
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
      d2ff8585
  19. 04 7月, 2015 2 次提交
    • J
      ahci: add rwerror=stop support for ncq · 7c03a691
      由 John Snow 提交于 
      Handle NCQ failures for cases where we want to halt the VM on IO errors.
Upon a VM state change, retry the halted NCQ commands.
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Message-id: 1435767578-32743-7-git-send-email-jsnow@redhat.com
      7c03a691
    • J
      ide: add limit to .prepare_buf() · a718978e
      由 John Snow 提交于 
      prepare_buf should not always grab as many descriptors
as it can, sometimes it should self-limit.

For example, an NCQ transfer of 1 sector with a PRDT that
describes 4GiB of data should not copy 4GiB of data, it
should just transfer that first 512 bytes.

PIO is not affected, because the dma_buf_rw dma helpers
already have a byte limit built-in to them, but DMA/NCQ
will exhaust the entire list regardless of requested size.

AHCI 1.3 specifies in section 6.1.6 Command List Underflow that
NCQ is not required to detect underflow conditions. Non-NCQ
pathways signal underflow by writing to the PRDBC field, which
will already occur by writing the actual transferred byte count
to the PRDBC, signaling the underflow.

Our NCQ pathways aren't required to detect underflow, but since our DMA
backend uses the size of the PRDT to determine the size of the transer,
if our PRDT is bigger than the transaction (the underflow condition) it
doesn't cost us anything to detect it and truncate the PRDT.

This is a recoverable error and is not signaled to the guest, in either
NCQ or normal DMA cases.

For BMDMA, the existing pathways should see no guest-visible difference,
but any bytes described in the overage will no longer be transferred
before indicating to the guest that there was an underflow.
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Message-id: 1435767578-32743-2-git-send-email-jsnow@redhat.com
      a718978e
  21. 12 6月, 2015 1 次提交
    • J
      migration: Use normal VMStateDescriptions for Subsections · 5cd8cada
      由 Juan Quintela 提交于 
      We create optional sections with this patch.  But we already have
optional subsections.  Instead of having two mechanism that do the
same, we can just generalize it.

For subsections we just change:

- Add a needed function to VMStateDescription
- Remove VMStateSubsection (after removal of the needed function
  it is just a VMStateDescription)
- Adjust the whole tree, moving the needed function to the corresponding
  VMStateDescription
Signed-off-by: NJuan Quintela <quintela@redhat.com>
      5cd8cada
  23. 28 4月, 2015 1 次提交
  25. 24 3月, 2015 2 次提交
  27. 10 3月, 2015 9 次提交
  29. 07 2月, 2015 1 次提交
  31. 19 11月, 2014 1 次提交
  33. 14 11月, 2014 2 次提交
    • J
      ide: Correct handling of malformed/short PRDTs · 3251bdcf
      由 John Snow 提交于 
      This impacts both BMDMA and AHCI HBA interfaces for IDE.
Currently, we confuse the difference between a PRDT having
"0 bytes" and a PRDT having "0 complete sectors."

When we receive an incomplete sector, inconsistent error checking
leads to an infinite loop wherein the call succeeds, but it
didn't give us enough bytes -- leading us to re-call the
DMA chain over and over again. This leads to, in the BMDMA case,
leaked memory for short PRDTs, and infinite loops and resource
usage in the AHCI case.

The .prepare_buf() callback is reworked to return the number of
bytes that it successfully prepared. 0 is a valid, non-error
answer that means the table was empty and described no bytes.
-1 indicates an error.

Our current implementation uses the io_buffer in IDEState to
ultimately describe the size of a prepared scatter-gather list.
Even though the AHCI PRDT/SGList can be as large as 256GiB, the
AHCI command header limits transactions to just 4GiB. ATA8-ACS3,
however, defines the largest transaction to be an LBA48 command
that transfers 65,536 sectors. With a 512 byte sector size, this
is just 32MiB.

Since our current state structures use the int type to describe
the size of the buffer, and this state is migrated as int32, we
are limited to describing 2GiB buffer sizes unless we change the
migration protocol.

For this reason, this patch begins to unify the assertions in the
IDE pathways that the scatter-gather list provided by either the
AHCI PRDT or the PCI BMDMA PRDs can only describe, at a maximum,
2GiB. This should be resilient enough unless we need a sector
size that exceeds 32KiB.

Further, the likelihood of any guest operating system actually
attempting to transfer this much data in a single operation is
very slim.

To this end, the IDEState variables have been updated to more
explicitly clarify our maximum supported size. Callers to the
prepare_buf callback have been reworked to understand the new
return code, and all versions of the prepare_buf callback have
been adjusted accordingly.

Lastly, the ahci_populate_sglist helper, relied upon by the
AHCI implementation of .prepare_buf() as well as the PCI
implementation of the callback have had overflow assertions
added to help make clear the reasonings behind the various
type changes.

[Added %d -> %"PRId64" fix John sent because off_pos changed from int to
int64_t.
--Stefan]
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 1414785819-26209-4-git-send-email-jsnow@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
      3251bdcf
    • J
      ide: repair PIO transfers for cases where nsector > 1 · 36334faf
      由 John Snow 提交于 
      Currently, for emulated PIO transfers through the AHCI device,
any attempt made to request more than a single sector's worth
of data will result in the same sector being transferred over
and over.

For example, if we request 8 sectors via PIO READ SECTORS, the
AHCI device will give us the same sector eight times.

This patch adds offset tracking into the PIO pathways so that
we can fulfill these requests appropriately.
Signed-off-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 1414785819-26209-2-git-send-email-jsnow@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
      36334faf