configure sa(4) to request no I/O splitting by default.
For tape devices, the user needs to be able to clearly understand
what blocksize is actually being used when writing to a tape
device. The previous behavior of physio(9) was that it would split
up any I/O that was too large for the device, or too large to fit
into MAXPHYS. This means that if, for instance, the user wrote a
1MB block to a tape device, and MAXPHYS was 128KB, the 1MB write
would be split into 8 128K chunks. This would be done without
informing the user.
This has suboptimal effects, especially when trying to communicate
status to the user. In the event of an error writing to a tape
(e.g. physical end of tape) in the middle of a 1MB block that has
been split into 8 pieces, the user could have the first two 128K
pieces written successfully, the third returned with an error, and
the last 5 returned with 0 bytes written. If the user is using
a standard write(2) system call, all he will see is the ENOSPC
error. He won't have a clue how much actually got written. (With
a writev(2) system call, he should be able to determine how much
got written in addition to the error.)
The solution is to prevent physio(9) from splitting the I/O. The
new cdev flag, SI_NOSPLIT, tells physio that the driver does not
want I/O to be split beforehand.
Although the sa(4) driver now enables SI_NOSPLIT by default,
that can be disabled by two loader tunables for now. It will not
be configurable starting in FreeBSD 11.0. kern.cam.sa.allow_io_split
allows the user to configure I/O splitting for all sa(4) driver
instances. kern.cam.sa.%d.allow_io_split allows the user to
configure I/O splitting for a specific sa(4) instance.
There are also now three sa(4) driver sysctl variables that let the
users see some sa(4) driver values. kern.cam.sa.%d.allow_io_split
shows whether I/O splitting is turned on. kern.cam.sa.%d.maxio shows
the maximum I/O size allowed by kernel configuration parameters
(e.g. MAXPHYS, DFLTPHYS) and the capabilities of the controller.
kern.cam.sa.%d.cpi_maxio shows the maximum I/O size supported by
the controller.
Note that a better long term solution would be to implement support
for chaining buffers, so that that MAXPHYS is no longer a limiting
factor for I/O size to tape and disk devices. At that point, the
controller and the tape drive would become the limiting factors.
sys/conf.h: Add a new cdev flag, SI_NOSPLIT, that allows a
driver to tell physio not to split up I/O.
sys/param.h: Bump __FreeBSD_version to 1000049 for the addition
of the SI_NOSPLIT cdev flag.
kern_physio.c: If the SI_NOSPLIT flag is set on the cdev, return
any I/O that is larger than si_iosize_max or
MAXPHYS, has more than one segment, or would have
to be split because of misalignment with EFBIG.
(File too large).
In the event of an error, print a console message to
give the user a clue about what happened.
scsi_sa.c: Set the SI_NOSPLIT cdev flag on the devices created
for the sa(4) driver by default.
Add tunables to control whether we allow I/O splitting
in physio(9).
Explain in the comments that allowing I/O splitting
will be deprecated for the sa(4) driver in FreeBSD
11.0.
Add sysctl variables to display the maximum I/O
size we can do (which could be further limited by
read block limits) and the maximum I/O size that
the controller can do.
Limit our maximum I/O size (recorded in the cdev's
si_iosize_max) by MAXPHYS. This isn't strictly
necessary, because physio(9) will limit it to
MAXPHYS, but it will provide some clarity for the
application.
Record the controller's maximum I/O size reported
in the Path Inquiry CCB.
sa.4: Document the block size behavior, and explain that
the option of allowing physio(9) to split the I/O
will disappear in FreeBSD 11.0.
Sponsored by: Spectra Logic
We now pay attention to the maxio field in the XPT_PATH_INQ CCB,
and if it is set, propagate it up to physio via the si_iosize_max
field in the cdev structure.
We also now pay attention to the PIM_UNMAPPED capability bit in the
XPT_PATH_INQ CCB, and set the new SI_UNMAPPED cdev flag when the
underlying SIM supports unmapped I/O.
scsi_sa.c: Add unmapped I/O support and propagate the SIM's
maximum I/O size up.
Adjust scsi_tape_read_write() in the same way that
scsi_read_write() was changed to support unmapped
I/O. We overload the readop parameter with bits
that tell us whether it's an unmapped I/O, and we
need to set the CAM_DATA_BIO CCB flag. This change
should be backwards compatible in source and
binary forms.
MFC after: 1 week
Sponsored by: Spectra Logic
While these operations are not really needed otherwise, at least for SCSI
they may cause extra errors if some other initiator holds write exclusive
reservation on the LUN (SYNCHRONIZE CACHE handled as "write" operation).
"Logical unit not supported" errors. First initiates specific target rescan,
second -- destroys specific LUN. That allows to automatically detect changes
in list of device LUNs. This mechanism doesn't work when target is completely
idle, but probably that is all what can be done without active polling.
Reviewed by: ken
Sponsored by: iXsystems, Inc.
changers that don't support the DVCID and CURDATA bits that were
introduced in the SMC spec.
These changers will return an Illegal Request type error if the
bits are set. This causes "chio status" to fail.
The fix is two-fold. First, for changers that claim to be SCSI-2
or older, don't set the DVCID and CURDATA bits for READ ELEMENT
STATUS. For newer changers (SCSI-3 and newer), we default to
setting the new bits, but back off and try the READ ELEMENT STATUS
without the bits if we get an Illegal Request type error.
This has been tested on a Qualstar TLS-8211, which is a SCSI-2
changer that does not support the new bits, and a Spectra T-380,
which is a SCSI-3 changer that does support the new bits. In the
absence of a SCSI-3 changer that does not support the bits, I
tested that with some error injection code. (The SMC spec says
that support for CURDATA is mandatory, and DVCID is optional.)
scsi_ch.c: Add a new quirk, CH_Q_NO_DVCID that gets set for
SCSI-2 and older libraries, or newer libraries that
report errors when the DVCID/CURDATA bits are set.
In chgetelemstatus(), use the new quirk to
determine whether or not to set DVCID and CURDATA.
If we get an error with the bits set, back off and
try without the bits. Set the quirk flag if the
read element status succeeds without the bits set.
Increase the READ ELEMENT STATUS timeout to 60
seconds after testing with a Spectra T-380. The
previous value was 10 seconds, and too short for
the T-380. This may be decreased later after
some additional testing and investigation.
Tested by: Andre Albsmeier <Andre.Albsmeier@siemens.com>
Sponsored by: Spectra Logic
MFC after: 3 days
Ensure that d_delmaxsize is always set, removing init to 0 which could cause
future issues if use cases change.
Allow kern.cam.da.X.delete_max (which maps to d_delmaxsize) to be increased
up to the calculated max after being reduced.
MFC after: 1 day
X-MFC-With: r249940
needed for the last 10 years. Far too much of the internal API is
exposed, and every small adjustment causes applications to stop working.
To kick this off, bump the API version to 0x17 as should have been done
with r246713, but add shims to compensate. Thanks to the shims, there
should be no visible change in application behavior.
I have plans to do a significant overhaul of the API to harnen it for
the future, but until then, I welcome others to add shims for older
versions of the API.
Obtained from: Netflix
SPC-4 specification states that serial number may be property of device,
but not a specific logical unit. People reported about FC storages using
serial number in that way, making it unusable for purposes of LUN multipath
detection. SPC-4 states that designators associated with logical unit from
the VPD page 83h "Device Identification" should be used for that purpose.
Report first of them in the new attribute in such preference order: NAA,
EUI-64, T10 and SCSI name string.
While there, make GEOM DISK properly report GEOM::ident in XML output also
using d_getattr() method, if available. This fixes serial numbers reporting
for SCSI disks in `geom disk list` output and confxml.
Discussed with: gibbs, ken
Sponsored by: iXsystems, Inc.
MFC after: 2 weeks
While GEOM in general has provider opened while sending BIO_GETATTR,
GEOM DISK does not really need to open disk to read medium-unrelated
attributes for own use.
Proposed by: ken
Re-ordered SSD quirks alphabetically so they are easier to maintain.
Removed my email and PR reference from comments on each quirk.
Added quirks for more SSDs:
* Crucial M4
* Corsair Force GT
* Intel 520 Series
* Kingston E100 Series
* Samsung 830 Series
Reviewed by: pjd (mentor)
Approved by: pjd (mentor)
MFC after: 1 week
This prevents users from selecting a delete method which may cause
corruption e.g. MPS WS16 on pre P14 firmware.
Reviewed by: pjd (mentor)
Approved by: pjd (mentor)
MFC after: 2 days
- remove DA_FLAG_SAW_MEDIA flag, almost opposite to DA_FLAG_PACK_INVALID,
using the last instead.
- allow opening device with no media present, reporting zero media size
and non-zero sector size, as geom/notes suggests. That allow to read
device attributes and potentially do other things, not related to media.
to query ATA functionality via ATA Pass-Through (16) as this page is defined
as "must" for SATL devices, hence indicating that the device is at least
likely to support Pass-Through (16).
This eliminates errors produced by CTL when ATA Pass-Through (16) fails.
Switch ATA probe daerror call to SF_NO_PRINT to avoid errors printing out
for devices which return invalid errors.
Output details about supported and choosen delete method when verbose booted.
Reviewed by: mav
Approved by: pjd (mentor)
MFC after: 1 week
Ensure that delete_available is reset so re-probes after a media change,
to one with different delete characteristics, will result in the correct
methods being flagged as available.
Make all ccb state changes use a consistent flow:
* free()
* xpt_release_ccb()
* softc->state = <new state>
* xpt_schedule()
Reviewed by: mav
Approved by: pjd (mentor)
MFC after: 1 week
Remove ADA_FLAG_PACK_INVALID flag. Since ATA disks have no concept of media
change it only duplicates CAM_PERIPH_INVALID flag, so we can use last one.
Slightly cleanup DA_FLAG_PACK_INVALID use.
requests.
sys/geom/geom_disk.h:
- Added d_delmaxsize which represents the maximum size of individual
device delete requests in bytes. This can be used by devices to
inform geom of their size limitations regarding delete operations
which are generally different from the read / write limits as data
is not usually transferred from the host to physical device.
sys/geom/geom_disk.c:
- Use new d_delmaxsize to calculate the size of chunks passed through to
the underlying strategy during deletes instead of using read / write
optimised values. This defaults to d_maxsize if unset (0).
- Moved d_maxsize default up so it can be used to default d_delmaxsize
sys/cam/ata/ata_da.c:
- Added d_delmaxsize calculations for TRIM and CFA
sys/cam/scsi/scsi_da.c:
- Added re-calculation of d_delmaxsize whenever delete_method is set.
- Added kern.cam.da.X.delete_max sysctl which allows the max size for
delete requests to be limited. This is useful in preventing timeouts
on devices who's delete methods are slow. It should be noted that
this limit is reset then the device delete method is changed and
that it can only be lowered not increased from the device max.
Reviewed by: mav
Approved by: pjd (mentor)
maximum sizes for said methods, which are used when processing BIO_DELETE
requests. This includes updating UNMAP support discovery to be based on
SBC-3 T10/1799-D Revision 31 specification.
Added ATA TRIM support to cam scsi devices via ATA Pass-Through(16)
sys/cam/scsi/scsi_da.c:
- Added ATA Data Set Management TRIM support via ATA Pass-Through(16)
as a delete_method
- Added four new probe states used to identity available methods and their
limits for the processing of BIO_DELETE commands via both UNMAP and the
new ATA TRIM commands.
- Renamed Probe states to better indicate their use
- Added delete method descriptions used when informing user of issues.
- Added automatic calculation of the optimum delete mode based on which
method presents the largest maximum request size as this is most likely
to result in the best performance.
- Added WRITE SAME max block limits
- Updated UNMAP range generation to mirror that used by ATA TRIM, this
optimises the generation of ranges and fixes a potential overflow
issue in the count when combining multiple BIO_DELETE requests
- Added output of warnings about short deletes. This should only ever
be triggered on devices that fail to correctly advertise their supported
delete modes / max sizes.
- Fixed WS16 requests being incorrectly limited to 65535 in length.
Reviewed by: mav
Approved by: pjd (mentor)
MFC after: 2 weeks
so its available for use in generic scsi code.
This is a pre-requirement for using VPD queries to determine available SCSI
delete methods within scsi_da.
Reviewed by: mav
Approved by: pjd (mentor)
MFC after: 2 weeks
commands to an ATA device attached via a SCSI control.
sys/cam/scsi/scsi_all.c:
- Added scsi_ata_identify, scsi_ata_trim
Which use ATA Pass-Through to send commands to the attached disk.
sys/cam/scsi/scsi_all.h:
- Added defines for all missing ATA Pass-Through commands values.
- Added scsi_ata_identify, scsi_ata_trim methods used in ATA TRIM
support.
- Added scsi_vpd_logical_block_prov structure used when querying for
the supported sizes UNMAP commands.
- Added scsi_vpd_block_limits structure used when querying for the
supported sizes of the UNMAP command.
Reviewed by: mav
Approved by: pjd (mentor)
MFC after: 2 weeks
This allows mapping a tape drive in a changer (as reported by
'chio status') to a sa(4) driver instance by comparing the
serial numbers.
The designators can be ASCII (which is printed out directly), binary
(which is printed in hex format) or UTF-8, which is printed in either
native UTF-8 format if the terminal can support it, or in %XX notation
for non-ASCII characters. Thanks to Hiroki Sato <hrs@> for the
explaining UTF-8 printing and example UTF-8 printing code.
chio.h: Modify the changer_element_status structure to add new
fields and definitions from the SMC3r16 spec.
Rename the original CHIOGSTATUS ioctl to OCHIOGTATUS and
define a new CHIOGSTATUS ioctl.
Clean up some tab/space issues.
chio.c: For the 'status' subcommand, print the designator field
if it is supplied by a device.
scsi_ch.h: Add new flags for DVCID and CURDATA to the READ
ELEMENT STATUS command structure.
Add a read_element_status_device_id structure
for the data fields in the new standard. Add new
unions, dt_or_obsolete and voltage_devid, to hold
and address data from either SCSI-2 or newer devices.
scsi_ch.c: Implement support for fetching device IDs with READ
ELEMENT STATUS data.
Add new arguments to scsi_read_element_status() to
allow the user to request the DVCID and CURDATA bits.
This isn't compiled into libcam (it's only an internal
kernel interface), so we don't need any special
handling for the API change.
If the user issues the new CHIOGSTATUS ioctl, copy all of
the available element status data out. If he issues the
OCHIOGSTATUS ioctl, we don't copy the new fields in the
structure.
Fix a bug in chopen() that would result in the peripheral
never getting unheld if chgetparams() failed.
Sponsored by: Spectra Logic
Submitted by: Po-Li Soong
MFC After: 1 week
