Commit graph

8 commits

Author SHA1 Message Date
Niklas Cassel 141354d55b hw/block/nvme: Add support for Namespace Types
Define the structures and constants required to implement
Namespace Types support.

Namespace Types introduce a new command set, "I/O Command Sets",
that allows the host to retrieve the command sets associated with
a namespace. Introduce support for the command set and enable
detection for the NVM Command Set.

The new workflows for identify commands rely heavily on zero-filled
identify structs. E.g., certain CNS commands are defined to return
a zero-filled identify struct when an inactive namespace NSID
is supplied.

Add a helper function in order to avoid code duplication when
reporting zero-filled identify structures.

Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
2021-02-08 20:58:34 +01:00
Dmitry Fomichev b52f26cd1f hw/block/nvme: Generate namespace UUIDs
In NVMe 1.4, a namespace must report an ID descriptor of UUID type
if it doesn't support EUI64 or NGUID. Add a new namespace property,
"uuid", that provides the user the option to either specify the UUID
explicitly or have a UUID generated automatically every time a
namespace is initialized.

Suggested-by: Klaus Jensen <k.jensen@samsung.com>
Signed-off-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Niklas Cassel <Niklas.Cassel@wdc.com>
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
2021-02-08 18:55:48 +01:00
Dmitry Fomichev ba69f22481 hw/block/nvme: Process controller reset and shutdown differently
Controller reset ans subsystem shutdown are handled very much the same
in the current code, but some of the steps should be different in these
two cases.

Introduce two new functions, nvme_reset_ctrl() and nvme_shutdown_ctrl(),
to separate some portions of the code from nvme_clear_ctrl(). The steps
that are made different between reset and shutdown are that BAR.CC is not
reset to zero upon the shutdown and namespace data is flushed to
backing storage as a part of shutdown handling, but not upon reset.

Suggested-by: Klaus Jensen <k.jensen@samsung.com>
Signed-off-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
2021-02-08 18:55:48 +01:00
Klaus Jensen 2605257a26 hw/block/nvme: add the dataset management command
Add support for the Dataset Management command and the Deallocate
attribute. Deallocation results in discards being sent to the underlying
block device. Whether of not the blocks are actually deallocated is
affected by the same factors as Write Zeroes (see previous commit).

     format | discard | dsm (512B)  dsm (4KiB)  dsm (64KiB)
    --------------------------------------------------------
      qcow2    ignore   n           n           n
      qcow2    unmap    n           n           y
      raw      ignore   n           n           n
      raw      unmap    n           y           y

Again, a raw format and 4KiB LBAs are preferable.

In order to set the Namespace Preferred Deallocate Granularity and
Alignment fields (NPDG and NPDA), choose a sane minimum discard
granularity of 4KiB. If we are using a passthru device supporting
discard at a 512B granularity, user should set the discard_granularity
property explicitly. NPDG and NPDA will also account for the
cluster_size of the block driver if required (i.e. for QCOW2).

See NVM Express 1.3d, Section 6.7 ("Dataset Management command").

Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
2021-02-08 18:55:48 +01:00
Klaus Jensen 54064e51d1 hw/block/nvme: add dulbe support
Add support for reporting the Deallocated or Unwritten Logical Block
Error (DULBE).

Rely on the block status flags reported by the block layer and consider
any block with the BDRV_BLOCK_ZERO flag to be deallocated.

Multiple factors affect when a Write Zeroes command result in
deallocation of blocks.

  * the underlying file system block size
  * the blockdev format
  * the 'discard' and 'logical_block_size' parameters

     format | discard | wz (512B)  wz (4KiB)  wz (64KiB)
    -----------------------------------------------------
      qcow2    ignore   n          n          y
      qcow2    unmap    n          n          y
      raw      ignore   n          y          y
      raw      unmap    n          y          y

So, this works best with an image in raw format and 4KiB LBAs, since
holes can then be punched on a per-block basis (this assumes a file
system with a 4kb block size, YMMV). A qcow2 image, uses a cluster size
of 64KiB by default and blocks will only be marked deallocated if a full
cluster is zeroed or discarded. However, this *is* consistent with the
spec since Write Zeroes "should" deallocate the block if the Deallocate
attribute is set and "may" deallocate if the Deallocate attribute is not
set. Thus, we always try to deallocate (the BDRV_REQ_MAY_UNMAP flag is
always set).

Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
2021-02-08 18:55:48 +01:00
Kevin Wolf 86b1cf3227 block: Separate blk_is_writable() and blk_supports_write_perm()
Currently, blk_is_read_only() tells whether a given BlockBackend can
only be used in read-only mode because its root node is read-only. Some
callers actually try to answer a slightly different question: Is the
BlockBackend configured to be writable, by taking write permissions on
the root node?

This can differ, for example, for CD-ROM devices which don't take write
permissions, but may be backed by a writable image file. scsi-cd allows
write requests to the drive if blk_is_read_only() returns false.
However, the write request will immediately run into an assertion
failure because the write permission is missing.

This patch introduces separate functions for both questions.
blk_supports_write_perm() answers the question whether the block
node/image file can support writable devices, whereas blk_is_writable()
tells whether the BlockBackend is currently configured to be writable.

All calls of blk_is_read_only() are converted to one of the two new
functions.

Fixes: https://bugs.launchpad.net/bugs/1906693
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20210118123448.307825-2-kwolf@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2021-01-27 20:45:20 +01:00
Dmitry Fomichev b865cabf73 hw/block/nvme: report actual LBA data shift in LBAF
Calculate the data shift value to report based on the set value of
logical_block_size device property.

In the process, use a local variable to calculate the LBA format
index instead of the hardcoded value 0. This makes the code more
readable and it will make it easier to add support for multiple LBA
formats in the future.

Signed-off-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
2020-10-27 11:29:25 +01:00
Klaus Jensen 7f0f1acedf hw/block/nvme: support multiple namespaces
This adds support for multiple namespaces by introducing a new 'nvme-ns'
device model. The nvme device creates a bus named from the device name
('id'). The nvme-ns devices then connect to this and registers
themselves with the nvme device.

This changes how an nvme device is created. Example with two namespaces:

  -drive file=nvme0n1.img,if=none,id=disk1
  -drive file=nvme0n2.img,if=none,id=disk2
  -device nvme,serial=deadbeef,id=nvme0
  -device nvme-ns,drive=disk1,bus=nvme0,nsid=1
  -device nvme-ns,drive=disk2,bus=nvme0,nsid=2

The drive property is kept on the nvme device to keep the change
backward compatible, but the property is now optional. Specifying a
drive for the nvme device will always create the namespace with nsid 1.

Signed-off-by: Klaus Jensen <k.jensen@samsung.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>
2020-10-27 07:24:47 +01:00