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| author | 2023-02-21 18:24:12 -0800 | |
|---|---|---|
| committer | 2023-02-21 18:24:12 -0800 | |
| commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
| tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /Documentation/scsi/scsi-changer.rst | |
| download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip | |
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski:
"Core:
- Add dedicated kmem_cache for typical/small skb->head, avoid having
to access struct page at kfree time, and improve memory use.
- Introduce sysctl to set default RPS configuration for new netdevs.
- Define Netlink protocol specification format which can be used to
describe messages used by each family and auto-generate parsers.
Add tools for generating kernel data structures and uAPI headers.
- Expose all net/core sysctls inside netns.
- Remove 4s sleep in netpoll if carrier is instantly detected on
boot.
- Add configurable limit of MDB entries per port, and port-vlan.
- Continue populating drop reasons throughout the stack.
- Retire a handful of legacy Qdiscs and classifiers.
Protocols:
- Support IPv4 big TCP (TSO frames larger than 64kB).
- Add IP_LOCAL_PORT_RANGE socket option, to control local port range
on socket by socket basis.
- Track and report in procfs number of MPTCP sockets used.
- Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
manager.
- IPv6: don't check net.ipv6.route.max_size and rely on garbage
collection to free memory (similarly to IPv4).
- Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).
- ICMP: add per-rate limit counters.
- Add support for user scanning requests in ieee802154.
- Remove static WEP support.
- Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
reporting.
- WiFi 7 EHT channel puncturing support (client & AP).
BPF:
- Add a rbtree data structure following the "next-gen data structure"
precedent set by recently added linked list, that is, by using
kfunc + kptr instead of adding a new BPF map type.
- Expose XDP hints via kfuncs with initial support for RX hash and
timestamp metadata.
- Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
better support decap on GRE tunnel devices not operating in collect
metadata.
- Improve x86 JIT's codegen for PROBE_MEM runtime error checks.
- Remove the need for trace_printk_lock for bpf_trace_printk and
bpf_trace_vprintk helpers.
- Extend libbpf's bpf_tracing.h support for tracing arguments of
kprobes/uprobes and syscall as a special case.
- Significantly reduce the search time for module symbols by
livepatch and BPF.
- Enable cpumasks to be used as kptrs, which is useful for tracing
programs tracking which tasks end up running on which CPUs in
different time intervals.
- Add support for BPF trampoline on s390x and riscv64.
- Add capability to export the XDP features supported by the NIC.
- Add __bpf_kfunc tag for marking kernel functions as kfuncs.
- Add cgroup.memory=nobpf kernel parameter option to disable BPF
memory accounting for container environments.
Netfilter:
- Remove the CLUSTERIP target. It has been marked as obsolete for
years, and we still have WARN splats wrt races of the out-of-band
/proc interface installed by this target.
- Add 'destroy' commands to nf_tables. They are identical to the
existing 'delete' commands, but do not return an error if the
referenced object (set, chain, rule...) did not exist.
Driver API:
- Improve cpumask_local_spread() locality to help NICs set the right
IRQ affinity on AMD platforms.
- Separate C22 and C45 MDIO bus transactions more clearly.
- Introduce new DCB table to control DSCP rewrite on egress.
- Support configuration of Physical Layer Collision Avoidance (PLCA)
Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
shared medium Ethernet.
- Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
preemption of low priority frames by high priority frames.
- Add support for controlling MACSec offload using netlink SET.
- Rework devlink instance refcounts to allow registration and
de-registration under the instance lock. Split the code into
multiple files, drop some of the unnecessarily granular locks and
factor out common parts of netlink operation handling.
- Add TX frame aggregation parameters (for USB drivers).
- Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
messages with notifications for debug.
- Allow offloading of UDP NEW connections via act_ct.
- Add support for per action HW stats in TC.
- Support hardware miss to TC action (continue processing in SW from
a specific point in the action chain).
- Warn if old Wireless Extension user space interface is used with
modern cfg80211/mac80211 drivers. Do not support Wireless
Extensions for Wi-Fi 7 devices at all. Everyone should switch to
using nl80211 interface instead.
- Improve the CAN bit timing configuration. Use extack to return
error messages directly to user space, update the SJW handling,
including the definition of a new default value that will benefit
CAN-FD controllers, by increasing their oscillator tolerance.
New hardware / drivers:
- Ethernet:
- nVidia BlueField-3 support (control traffic driver)
- Ethernet support for imx93 SoCs
- Motorcomm yt8531 gigabit Ethernet PHY
- onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
- Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
- Amlogic gxl MDIO mux
- WiFi:
- RealTek RTL8188EU (rtl8xxxu)
- Qualcomm Wi-Fi 7 devices (ath12k)
- CAN:
- Renesas R-Car V4H
Drivers:
- Bluetooth:
- Set Per Platform Antenna Gain (PPAG) for Intel controllers.
- Ethernet NICs:
- Intel (1G, igc):
- support TSN / Qbv / packet scheduling features of i226 model
- Intel (100G, ice):
- use GNSS subsystem instead of TTY
- multi-buffer XDP support
- extend support for GPIO pins to E823 devices
- nVidia/Mellanox:
- update the shared buffer configuration on PFC commands
- implement PTP adjphase function for HW offset control
- TC support for Geneve and GRE with VF tunnel offload
- more efficient crypto key management method
- multi-port eswitch support
- Netronome/Corigine:
- add DCB IEEE support
- support IPsec offloading for NFP3800
- Freescale/NXP (enetc):
- support XDP_REDIRECT for XDP non-linear buffers
- improve reconfig, avoid link flap and waiting for idle
- support MAC Merge layer
- Other NICs:
- sfc/ef100: add basic devlink support for ef100
- ionic: rx_push mode operation (writing descriptors via MMIO)
- bnxt: use the auxiliary bus abstraction for RDMA
- r8169: disable ASPM and reset bus in case of tx timeout
- cpsw: support QSGMII mode for J721e CPSW9G
- cpts: support pulse-per-second output
- ngbe: add an mdio bus driver
- usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
- r8152: handle devices with FW with NCM support
- amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
- virtio-net: support multi buffer XDP
- virtio/vsock: replace virtio_vsock_pkt with sk_buff
- tsnep: XDP support
- Ethernet high-speed switches:
- nVidia/Mellanox (mlxsw):
- add support for latency TLV (in FW control messages)
- Microchip (sparx5):
- separate explicit and implicit traffic forwarding rules, make
the implicit rules always active
- add support for egress DSCP rewrite
- IS0 VCAP support (Ingress Classification)
- IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
etc.)
- ES2 VCAP support (Egress Access Control)
- support for Per-Stream Filtering and Policing (802.1Q,
8.6.5.1)
- Ethernet embedded switches:
- Marvell (mv88e6xxx):
- add MAB (port auth) offload support
- enable PTP receive for mv88e6390
- NXP (ocelot):
- support MAC Merge layer
- support for the the vsc7512 internal copper phys
- Microchip:
- lan9303: convert to PHYLINK
- lan966x: support TC flower filter statistics
- lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
- lan937x: support Credit Based Shaper configuration
- ksz9477: support Energy Efficient Ethernet
- other:
- qca8k: convert to regmap read/write API, use bulk operations
- rswitch: Improve TX timestamp accuracy
- Intel WiFi (iwlwifi):
- EHT (Wi-Fi 7) rate reporting
- STEP equalizer support: transfer some STEP (connection to radio
on platforms with integrated wifi) related parameters from the
BIOS to the firmware.
- Qualcomm 802.11ax WiFi (ath11k):
- IPQ5018 support
- Fine Timing Measurement (FTM) responder role support
- channel 177 support
- MediaTek WiFi (mt76):
- per-PHY LED support
- mt7996: EHT (Wi-Fi 7) support
- Wireless Ethernet Dispatch (WED) reset support
- switch to using page pool allocator
- RealTek WiFi (rtw89):
- support new version of Bluetooth co-existance
- Mobile:
- rmnet: support TX aggregation"
* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
page_pool: add a comment explaining the fragment counter usage
net: ethtool: fix __ethtool_dev_mm_supported() implementation
ethtool: pse-pd: Fix double word in comments
xsk: add linux/vmalloc.h to xsk.c
sefltests: netdevsim: wait for devlink instance after netns removal
selftest: fib_tests: Always cleanup before exit
net/mlx5e: Align IPsec ASO result memory to be as required by hardware
net/mlx5e: TC, Set CT miss to the specific ct action instance
net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
net/mlx5: Refactor tc miss handling to a single function
net/mlx5: Kconfig: Make tc offload depend on tc skb extension
net/sched: flower: Support hardware miss to tc action
net/sched: flower: Move filter handle initialization earlier
net/sched: cls_api: Support hardware miss to tc action
net/sched: Rename user cookie and act cookie
sfc: fix builds without CONFIG_RTC_LIB
sfc: clean up some inconsistent indentings
net/mlx4_en: Introduce flexible array to silence overflow warning
net: lan966x: Fix possible deadlock inside PTP
net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
...
Diffstat (limited to '')
| -rw-r--r-- | Documentation/scsi/scsi-changer.rst | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/Documentation/scsi/scsi-changer.rst b/Documentation/scsi/scsi-changer.rst new file mode 100644 index 000000000..ab60e7e61 --- /dev/null +++ b/Documentation/scsi/scsi-changer.rst @@ -0,0 +1,184 @@ +.. SPDX-License-Identifier: GPL-2.0 + +======================================== +README for the SCSI media changer driver +======================================== + +This is a driver for SCSI Medium Changer devices, which are listed +with "Type: Medium Changer" in /proc/scsi/scsi. + +This is for *real* Jukeboxes. It is *not* supported to work with +common small CD-ROM changers, neither one-lun-per-slot SCSI changers +nor IDE drives. + +Userland tools available from here: + http://linux.bytesex.org/misc/changer.html + + +General Information +------------------- + +First some words about how changers work: A changer has 2 (possibly +more) SCSI ID's. One for the changer device which controls the robot, +and one for the device which actually reads and writes the data. The +later may be anything, a MOD, a CD-ROM, a tape or whatever. For the +changer device this is a "don't care", he *only* shuffles around the +media, nothing else. + + +The SCSI changer model is complex, compared to - for example - IDE-CD +changers. But it allows to handle nearly all possible cases. It knows +4 different types of changer elements: + + =============== ================================================== + media transport this one shuffles around the media, i.e. the + transport arm. Also known as "picker". + storage a slot which can hold a media. + import/export the same as above, but is accessible from outside, + i.e. there the operator (you !) can use this to + fill in and remove media from the changer. + Sometimes named "mailslot". + data transfer this is the device which reads/writes, i.e. the + CD-ROM / Tape / whatever drive. + =============== ================================================== + +None of these is limited to one: A huge Jukebox could have slots for +123 CD-ROM's, 5 CD-ROM readers (and therefore 6 SCSI ID's: the changer +and each CD-ROM) and 2 transport arms. No problem to handle. + + +How it is implemented +--------------------- + +I implemented the driver as character device driver with a NetBSD-like +ioctl interface. Just grabbed NetBSD's header file and one of the +other linux SCSI device drivers as starting point. The interface +should be source code compatible with NetBSD. So if there is any +software (anybody knows ???) which supports a BSDish changer driver, +it should work with this driver too. + +Over time a few more ioctls where added, volume tag support for example +wasn't covered by the NetBSD ioctl API. + + +Current State +------------- + +Support for more than one transport arm is not implemented yet (and +nobody asked for it so far...). + +I test and use the driver myself with a 35 slot cdrom jukebox from +Grundig. I got some reports telling it works ok with tape autoloaders +(Exabyte, HP and DEC). Some People use this driver with amanda. It +works fine with small (11 slots) and a huge (4 MOs, 88 slots) +magneto-optical Jukebox. Probably with lots of other changers too, most +(but not all :-) people mail me only if it does *not* work... + +I don't have any device lists, neither black-list nor white-list. Thus +it is quite useless to ask me whenever a specific device is supported or +not. In theory every changer device which supports the SCSI-2 media +changer command set should work out-of-the-box with this driver. If it +doesn't, it is a bug. Either within the driver or within the firmware +of the changer device. + + +Using it +-------- + +This is a character device with major number is 86, so use +"mknod /dev/sch0 c 86 0" to create the special file for the driver. + +If the module finds the changer, it prints some messages about the +device [ try "dmesg" if you don't see anything ] and should show up in +/proc/devices. If not.... some changers use ID ? / LUN 0 for the +device and ID ? / LUN 1 for the robot mechanism. But Linux does *not* +look for LUNs other than 0 as default, because there are too many +broken devices. So you can try: + + 1) echo "scsi add-single-device 0 0 ID 1" > /proc/scsi/scsi + (replace ID with the SCSI-ID of the device) + 2) boot the kernel with "max_scsi_luns=1" on the command line + (append="max_scsi_luns=1" in lilo.conf should do the trick) + + +Trouble? +-------- + +If you insmod the driver with "insmod debug=1", it will be verbose and +prints a lot of stuff to the syslog. Compiling the kernel with +CONFIG_SCSI_CONSTANTS=y improves the quality of the error messages a lot +because the kernel will translate the error codes into human-readable +strings then. + +You can display these messages with the dmesg command (or check the +logfiles). If you email me some question because of a problem with the +driver, please include these messages. + + +Insmod options +-------------- + +debug=0/1 + Enable debug messages (see above, default: 0). + +verbose=0/1 + Be verbose (default: 1). + +init=0/1 + Send INITIALIZE ELEMENT STATUS command to the changer + at insmod time (default: 1). + +timeout_init=<seconds> + timeout for the INITIALIZE ELEMENT STATUS command + (default: 3600). + +timeout_move=<seconds> + timeout for all other commands (default: 120). + +dt_id=<id1>,<id2>,... / dt_lun=<lun1>,<lun2>,... + These two allow to specify the SCSI ID and LUN for the data + transfer elements. You likely don't need this as the jukebox + should provide this information. But some devices don't ... + +vendor_firsts=, vendor_counts=, vendor_labels= + These insmod options can be used to tell the driver that there + are some vendor-specific element types. Grundig for example + does this. Some jukeboxes have a printer to label fresh burned + CDs, which is addressed as element 0xc000 (type 5). To tell the + driver about this vendor-specific element, use this:: + + $ insmod ch \ + vendor_firsts=0xc000 \ + vendor_counts=1 \ + vendor_labels=printer + + All three insmod options accept up to four comma-separated + values, this way you can configure the element types 5-8. + You likely need the SCSI specs for the device in question to + find the correct values as they are not covered by the SCSI-2 + standard. + + +Credits +------- + +I wrote this driver using the famous mailing-patches-around-the-world +method. With (more or less) help from: + + - Daniel Moehwald <moehwald@hdg.de> + - Dane Jasper <dane@sonic.net> + - R. Scott Bailey <sbailey@dsddi.eds.com> + - Jonathan Corbet <corbet@lwn.net> + +Special thanks go to + + - Martin Kuehne <martin.kuehne@bnbt.de> + +for a old, second-hand (but full functional) cdrom jukebox which I use +to develop/test driver and tools now. + +Have fun, + + Gerd + +Gerd Knorr <kraxel@bytesex.org> |
