Notable upstream pull request merges:
#16209 --multi-- icp: rip out everything we don't use
#1623020c8bdd85 FreeBSD: Update use of UMA-related symbols in
arc_available_memory
#16242121a2d335 FreeBSD: unregister mountroot eventhandler on unload
#162585de3ac223 vdev_open: clear async fault flag after reopen
#16270436731276 zvol: Fix suspend lock leaks
#16273c87cb22ba head_errlog: fix use-after-free
#16284f72e081fb FreeBSD: Use a statement expression to implement
SET_ERROR()
#16300a10faf5ce FreeBSD: Use the new freeuio() helper to free dynamically
allocated UIOs
#16302a7fc4c85e zstd: don't call zstd_mempool_reap if there are no buffers
#16334dc91e7452 zdb: dump ZAP_FLAG_UINT64_KEY ZAPs properly
Obtained from: OpenZFS
OpenZFS commit: 1147a27978
These are only included in the amd64 vmm code, so it doesn't make sense
to list them unconditionally.
PR: 280171
Reviewed by: wosch, imp, emaste
Differential Revision: https://reviews.freebsd.org/D45964
Inline IPSEC offload moves almost whole IPSEC processing from the
CPU/MCU and possibly crypto accelerator, to the network card.
The transmitted packet content is not touched by CPU during TX
operations, kernel only does the required policy and security
association lookups to find out that given flow is offloaded, and then
packet is transmitted as plain text to the card. For driver convenience,
a metadata is attached to the packet identifying SA which must process
the packet. Card does encryption of the payload, padding, calculates
authentication, and does the reformat according to the policy.
Similarly, on receive, card does the decapsulation, decryption, and
authentification. Kernel receives the identifier of SA that was
used to process the packet, together with the plain-text packet.
Overall, payload octets are only read or written by card DMA engine,
removing a lot of memory subsystem overhead, and saving CPU time because
IPSEC algos calculations are avoided.
If driver declares support for inline IPSEC offload (with the
IFCAP2_IPSEC_OFFLOAD capability set and registering method table struct
if_ipsec_accel_methods), kernel offers the SPD and SAD to driver.
Driver decides which policies and SAs can be offloaded based on
hardware capacity, and acks/nacks each SA for given interface to
kernel. Kernel needs to keep this information to make a decision to
skip software processing on TX, and to assume processing already done
on RX. This shadow SPD/SAD database of offloads is rooted from
policies (struct secpolicy accel_ifps, struct ifp_handle_sp) and SAs
(struct secasvar accel_ipfs, struct ifp_handle_sav).
Some extensions to the PF_KEY socket allow to limit interfaces for
which given SP/SA could be offloaded (proposed for offload). Also,
additional statistics extensions allow to observe allocation/octet/use
counters for specific SA.
Since SPs and SAs are typically instantiated in non-sleepable context,
while offloading them into card is expected to require costly async
manipulations of the card state, calls to the driver for offload and
termination are executed in the threaded taskqueue. It also solves
the issue of allocating resources needed for the offload database.
Neither ipf_handle_sp nor ipf_handle_sav do not add reference to the
owning SP/SA, the offload must be terminated before last reference is
dropped. ipsec_accel only adds transient references to ensure safe
pointer ownership by taskqueue.
Maintaining the SA counters for hardware-accelerated packets is the
duty of the driver. The helper ipsec_accel_drv_sa_lifetime_update()
is provided to hide accel infrastructure from drivers which would use
expected callout to query hardware periodically for updates.
Reviewed by: rscheff (transport, stack integration), np
Sponsored by: NVIDIA networking
Differential revision: https://reviews.freebsd.org/D44219
We're building ACPI, so we need -DDEV_ACPI on CFLAGS. Nomally, the
kernel config brings this in, but there's no kernel directory for the
standalone build.
Sponsored by: Netflix
Summary:
Add support for building ossl(4) on powerpc64* by implementing ossl_cpuid and
other support functions for powerpc. The required assembly files for ppc were
already present in-tree.
Test Plan: The changes were tested using the in-tree tools/tools/crypto/cryptocheck.c tool on both powerpc64 and powerpc64le on a POWER9 system.
Reviewed by: #powerpc, jhibbits, jhb
Differential Revision: https://reviews.freebsd.org/D41837
The idea here is to avoid a memory access and conditional branch per
probe site. Instead, the probe is represented by an "unreachable"
unconditional function call. asm goto is used to store the address of
the probe site (represented by a no-op sled) and the address of the
function call into a tracepoint record. Each SDT probe carries a list
of tracepoints.
When the probe is enabled, the no-op sled corresponding to each
tracepoint is overwritten with a jmp to the corresponding label. The
implementation uses smp_rendezvous() to park all other CPUs while the
instruction is being overwritten, as this can't be done atomically in
general. The compiler moves argument marshalling code and the
sdt_probe() function call out-of-line, i.e., to the end of the function.
Per gallatin@ in D43504, this approach has less overhead when probes are
disabled. To make the implementation a bit simpler, I removed support
for probes with 7 arguments; nothing makes use of this except a
regression test case. It could be re-added later if need be.
The approach taken in this patch enables some more improvements:
1. We can now automatically fill out the "function" field of SDT probe
names. The SDT macros let the programmer specify the function and
module names, but this is really a bug and shouldn't have been
allowed. The intent was to be able to have the same probe in
multiple functions and to let the user restrict which probes actually
get enabled by specifying a function name or glob.
2. We can avoid branching on SDT_PROBES_ENABLED() by adding the ability
to include blocks of code in the out-of-line path. For example:
if (SDT_PROBES_ENABLED()) {
int reason = CLD_EXITED;
if (WCOREDUMP(signo))
reason = CLD_DUMPED;
else if (WIFSIGNALED(signo))
reason = CLD_KILLED;
SDT_PROBE1(proc, , , exit, reason);
}
could be written
SDT_PROBE1_EXT(proc, , , exit, reason,
int reason;
reason = CLD_EXITED;
if (WCOREDUMP(signo))
reason = CLD_DUMPED;
else if (WIFSIGNALED(signo))
reason = CLD_KILLED;
);
In the future I would like to use this mechanism more generally, e.g.,
to remove branches and marshalling code used by hwpmc, and generally to
make it easier to add new tracepoint consumers without having to add
more conditional branches to hot code paths.
Reviewed by: Domagoj Stolfa, avg
MFC after: 2 months
Differential Revision: https://reviews.freebsd.org/D44483
This is derived from swills@ fork of the Juniper virtfs with many
changes by me including bug fixes, style improvements, clearer layering
and more consistent logging. The filesystem is renamed to p9fs to better
reflect its function and to prevent possible future confusion with
virtio-fs.
Several updates and fixes from Juniper have been integrated into this
version by Val Packett and these contributions along with the original
Juniper authors are credited below.
To use this with bhyve, add 'virtio_p9fs_load=YES' to loader.conf. The
bhyve virtio-9p device allows access from the guest to files on the host
by mapping a 'sharename' to a host path. It is possible to use p9fs as a
root filesystem by adding this to /boot/loader.conf:
vfs.root.mountfrom="p9fs:sharename"
for non-root filesystems add something like this to /etc/fstab:
sharename /mnt p9fs rw 0 0
In both examples, substitute the share name used on the bhyve command
line.
The 9P filesystem protocol relies on stateful file opens which map
protocol-level FIDs to host file descriptors. The FreeBSD vnode
interface doesn't really support this and we use heuristics to guess the
right FID to use for file operations. This can be confused by privilege
lowering and does not guarantee that the FID created for a given file
open is always used for file operations, even if the calling process is
using the file descriptor from the original open call. Improving this
would involve changes to the vnode interface which is out-of-scope for
this import.
Differential Revision: https://reviews.freebsd.org/D41844
Reviewed by: kib, emaste, dch
MFC after: 3 months
Co-authored-by: Val Packett <val@packett.cool>
Co-authored-by: Ka Ho Ng <kahon@juniper.net>
Co-authored-by: joyu <joyul@juniper.net>
Co-authored-by: Kumara Babu Narayanaswamy <bkumara@juniper.net>
This code runs at EL2 while the kernel runs at EL1. We build these
files for EL2 through a dependency in vmm_hyp_blob.elf.full so there
is no need to include them in SRCS.
Reviewed by: imp, kib, markj
Sponsored by: Arm Ltd
Differential Revision: https://reviews.freebsd.org/D45467
Currently FreeBSD uses IPI based TLB flushing for remote
TLB flushing. Hyper-V allows hypercalls to flush local and
remote TLB. The use of Hyper-V hypercalls gives significant
performance improvement in TLB operations.
This patch set during test has shown near to 40 percent
TLB performance improvement.
Also this patch adds rep hypercall implementation as well.
Reviewed by: whu, kib
Tested by: whu
Authored-by: Souradeep Chakrabarti <schakrabarti@microsoft.com>
Co-Authored-by: Erni Sri Satya Vennela <ernis@microsoft.com>
MFC after: 1 week
Sponsored by: Microsoft
Differential Revision: https://reviews.freebsd.org/D45521
Firmware advertises the transfer lenght for writesame commands to driver during init.
So for any writesame IOs with ndob and unmap bit set and transfer lengh is greater
than the max write same length specified by the firmware, then direct those commands
to firmware instead of hardware otherwise hardware will break.
Reviewed by: imp
Approved by: imp
Differential revision: https://reviews.freebsd.org/D44452
When we enable checking for BTI on arm64 we need to include an ELF
note in all object files linked into a module.
As using objcopy from a binary to an ELF object file doesn't add the
note switch to using .incbin from an assembly file. This allows us to
add the needed note without affecting the included object.
Reviewed by: imp, kib, emaste
Sponsored by: Arm Ltd
Differential Revision: https://reviews.freebsd.org/D45468
LLD has the -zbti-report=error argument to check if the BTI note is
present when linking. To allow for this to be used when linking the
kernel and modules:
- Add the BTI note to the remaining assembly files
- Mark ptrauth.c as protected by BTI
- Disable -zbti-report for vmm hypervisor switching code as it's not
used there.
The linux64 module doesn't build with the flag as it includes vdso code
that doesn't include the note.
Reviewed by: imp, kib, emaste
Sponsored by: Arm Ltd
Differential Revision: https://reviews.freebsd.org/D45466
Notable upstream pull request merges:
#1594041ae864b6 Replace P2ALIGN with P2ALIGN_TYPED and delete P2ALIGN
#161285137c132a zpool import output is not formated properly
#16138efbef9e6c FreeBSD: Add zfs_link_create() error handling
#1614604bae5ec9 Disable high priority ZIO threads on FreeBSD and Linux
#16151cc3869153 zfs_ioc_send: use a dedicated taskq thread for send
#16151adda768e3 spa: remove spa_taskq_dispatch_sync()
#16151515c4dd21 spa: flatten spa_taskq_dispatch_ent()
#161510a543db37 spa_taskq_dispatch_ent: simplify arguments
#16153975a13259 Add support for parallel pool exports
#1615389acef992 Simplified the scope of the namespace lock
#16159136c05321 ZAP: Fix leaf references on zap_expand_leaf() errors
#16162af5dbed31 Fix scn_queue races on very old pools
#161653400127a7 Fix ZIL clone records for legacy holes
#16167414acbd37 Unbreak FreeBSD cross-build on MacOS broken in 051460b8b#16172eced2e2f1 libzfs: Fix mounting datasets under thread limit pressure
#16178b64afa41d Better control the thread pool size when mounting datasets
#16181fa99d9cd9 zfs_dbgmsg_print: make FreeBSD and Linux consistent
#16191e675852bc dbuf: separate refcount calls for dbuf and dbuf_user
#16198a043b60f1 Correct level handling in zstream recompress
#1620434906f8bb zap: reuse zap_leaf_t on dbuf reuse after shrink
#16206d0aa9dbcc Use memset to zero stack allocations containing unions
#162078865dfbca Fix assertion in Persistent L2ARC
#1620808648cf0d Allow block cloning to be interrupted by a signal
#16210e2357561b FreeBSD: Add const qualifier to members of struct
opensolaris_utsname
#16214800d59d57 Some improvements to metaslabs eviction
#1621602c5aa9b0 Destroy ARC buffer in case of fill error
#1622501c8efdd5 Simplify issig()
Obtained from: OpenZFS
OpenZFS commit: e2357561b9
LINT includes bnxt_re driver. Adjust the path in files, add missing
files and add a new BNXT_C to build (which thinly wraps OFED version
with bnxt specicif stuff).
Sponsored by: Netflix
Fixes: acd884dec9 ("RDMA/bnxt_re: Add bnxt_re RoCE driver")
The new bnxt_re driver doesn't compile on any of them (it uses writeq()
from the LinuxKPI, which isn't implemented there), and had already been
disconnected from the build on i386.
Reported by: Jenkins
Fixes: acd884dec9 ("RDMA/bnxt_re: Add bnxt_re RoCE driver")
This patch introduces the RoCE driver for the
Broadcom NetXtreme-E 10/25/50/100/200G RoCE HCAs.
The RoCE driver is a two part driver that relies
on the bnxt_en NIC driver to operate. The changes
needed in the bnxt_en driver is included through
another patch "L2-RoCE driver communication interface"
in this set.
Presently, There is no user space support, Hence
recommendation to use the krping kernel module for
testing. User space support will be incorporated in
subsequent patch submissions.
Reviewed by: imp
Approved by: imp
Differential revision: https://reviews.freebsd.org/D45011
- Added Aux bus support for RoCE.
- Implemented the ulp ops that are required by RoCE driver.
- Restructure context memory data structures
- DBR pacing support
Reviewed by: imp
Approved by: imp
Differential revision: https://reviews.freebsd.org/D45006
Created new directory "bnxt_en" in /dev/bnxt and /modules/bnxt
and moved source files and Makefile into respective directory.
ETS support:
- Added new files bnxt_dcb.c & bnxt_dcb.h
- Added sysctl node 'dcb' and created handlers 'ets' and
'dcbx_cap'
- Add logic to validate user input and configure ETS in
the firmware
- Updated makefile to include bnxt_dcb.c & bnxt_dcb.h
PFC support:
- Created sysctl handlers 'pfc' under node 'dcb'
- Added logic to validate user input and configure PFC in
the firmware.
App TLV support:
- Created 3 new sysctl handlers under node 'dcb'
- set_apptlv (write only): Sets a specified TLV
- del_apptlv (write only): Deletes a specified TLV
- list_apptlv (read only): Lists all APP TLVs configured
- Added logic to validate user input and configure APP TLVs
in the firmware.
Added Below DCB ops for management interface:
- Set PFC, Get PFC, Set ETS, Get ETS, Add App_TLV, Del App_TLV
Lst App_TLV
Reviewed by: imp
Approved by: imp
Differential revision: https://reviews.freebsd.org/D45005
This policy enables a user to become another user without having to be
root (hence no setuid binary). it is configured via rules using sysctl
security.mac.do.rules
For example:
security.mac.do.rules=uid=1001:80,gid=0:any
The above rule means the user identifier by the uid 1001 is able to
become user 80
Any user of the group 0 are allowed to become any user on the system.
The mdo(1) utility expects the MAC/do policy to be installed and its
rules defined.
Reviewed by: des
Differential Revision: https://reviews.freebsd.org/D45145
Use .PATH & bare filename. This prevents the real source path from
being included in the built object, which improves reproducibility.
Signed-off-by: Dan McGregor <dan.mcgregor@usask.ca>
Reviewed by: imp
Pull Request: https://github.com/freebsd/freebsd-src/pull/1211
Add a sound(4) bridge device driver for the RME HDSP 9632 and HDSP 9652
sound cards. These cards require a nowadays rare PCI 32bit (not PCIe)
slot, but still see use due to their value and wealth of features.
The HDSP 9632 is mostly comparable to the newer HDSPe AIO, while the
HDSP 9652 is similar to the HDSPe RayDAT. These HDSPe PCIe cards are
supported by the snd_hdspe(4) driver which was taken as a starting point
for development of snd_hdsp(4).
Implementation is kept separately due to substantial differences in
hardware configuration and to allow easy removal in case PCI 32bit
support would be phased out in the future.
The snd_hdsp(4) kernel module is not enabled by default, and can be
loaded at runtime with kldload(8) or during boot via loader.conf(5).
Basic operation was tested with both cards, not including all optional
cable connectors and expansion boards. Features should be roughly on par
with the snd_hdspe(4) supported cards.
Reviewed by: christos, br
Differential Revision: https://reviews.freebsd.org/D45112
The ROCK 4C Plus is a cost-reduced variant of the ROCK Pi 4 based on
the RockChip RK3399-T.
Reviewed by: manu
MFC after: 1 week
Differential Revision: <https://reviews.freebsd.org/D45110
aicasm just puts the value of the "-i" passed include file in the
generated file with quotes around it. This means that there are manual
edits made to aic7xxx_reg_print.c and aic79xx_reg_print.c
now we check to see if the value passed to '-i' starts with a '<', if it
does don't output the quotes.
Signed-off-by: HP van Braam <hp@tmm.cx>
Reviewed by: imp (minor code simplification)
Pull Request: https://github.com/freebsd/freebsd-src/pull/1209
Summary:
Though mostly used in x86 devices, TPM can be used on others, with a
direct SPI attachment. Refactor the TPM 2.0 driver set to use an
attachment interface, and implement a SPI bus interface.
Test Plan:
Tested on a Raspberry Pi 4, with a GeeekPi TPM2.0 module (SLB9670
TPM) using security/tpm2-tools tpm2_getcaps for very light testing against the
spibus attachment.
Reviewed by: kd
Obtained from: Juniper Networks, Inc.
Differential Revision: https://reviews.freebsd.org/D45069
Notable upstream pull request merges:
#15839c3f2f1aa2 vdev probe to slow disk can stall mmp write checker
#158885044c4e3f Fast Dedup: ZAP Shrinking
#15996db499e68f Overflowing refreservation is bad
#1611867d13998b Make more taskq parameters writable
#1612821bc066ec Fix updating the zvol_htable when renaming a zvol
#16130645b83307 Improve write issue taskqs utilization
#161318fd3a5d02 Slightly improve dnode hash
#16134a6edc0adb zio: try to execute TYPE_NULL ZIOs on the current task
#16141b28461b7c Fix arcstats for FreeBSD after zfetch support
Obtained from: OpenZFS
OpenZFS commit: 8f1b7a6fa6
This is the server (target in SCSI terms) for NVMe over Fabrics.
Userland is responsible for accepting a new queue pair and receiving
the initial Connect command before handing the queue pair off via an
ioctl to this CTL frontend.
This frontend exposes CTL LUNs as NVMe namespaces to remote hosts.
Users can ask LUNS to CTL that can be shared via either iSCSI or
NVMeoF.
Reviewed by: imp
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D44726
- Add support for queueing and executing NVMe admin and NVM commands
via ctl_run and ctl_queue. This requires fixing a few places that
were SCSI-specific to add NVME logic.
- NVMe has much simpler command ordering requirements than SCSI. In
particular, the HBA is not required to enforce any specific ordering
for requests with overlapping LBAs. The host is required to manage
that ordering. However, fused commands (currently only COMPARE and
WRITE NVM commands can be fused) are required to be executed
atomically.
To support fused commands, make the second half of a fused command
block on the first half, and have commands submitted after a fused
command pair block on the second half.
- Add handlers and command tables for admin and NVM commands that
operate on individual namespaces and will be passed down from an
NVMe over Fabrics controller to a CTL LUN.
Reviewed by: ken, imp
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D44720
This is the client (initiator in SCSI terms) for NVMe over Fabrics.
Userland is responsible for creating a set of queue pairs and then
handing them off via an ioctl to this driver, e.g. via the 'connect'
command from nvmecontrol(8). An nvmeX new-bus device is created
at the top-level to represent the remote controller similar to PCI
nvmeX devices for PCI-express controllers.
As with nvme(4), namespace devices named /dev/nvmeXnsY are created and
pass through commands can be submitted to either the namespace devices
or the controller device. For example, 'nvmecontrol identify nvmeX'
works for a remote Fabrics controller the same as for a PCI-express
controller.
nvmf exports remote namespaces via nda(4) devices using the new NVMF
CAM transport. nvmf does not support nvd(4), only nda(4).
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D44714
Structurally this is very similar to the TCP transport for iSCSI
(icl_soft.c). One key difference is that NVMeoF transports use a more
abstract interface working with NVMe commands rather than transport
PDUs. Thus, the data transfer for a given command is managed entirely
in the transport backend.
Similar to icl_soft.c, separate kthreads are used to handle transmit
and receive for each queue pair. On the transmit side, when a capsule
is transmitted by an upper layer, it is placed on a queue for
processing by the transmit thread. The transmit thread converts
command response capsules into suitable TCP PDUs where each PDU is
described by an mbuf chain that is then queued to the backing socket's
send buffer. Command capsules can embed data along with the NVMe
command.
On the receive side, a socket upcall notifies the receive kthread when
more data arrives. Once enough data has arrived for a PDU, the PDU is
handled synchronously in the kthread. PDUs such as R2T or data
related PDUs are handled internally, with callbacks invoked if a data
transfer encounters an error, or once the data transfer has completed.
Received capsule PDUs invoke the upper layer's capsule_received
callback.
struct nvmf_tcp_command_buffer manages a TCP command buffer for data
transfers that do not use in-capsule-data as described in the NVMeoF
spec. Data related PDUs such as R2T, C2H, and H2C are associated with
a command buffer except in the case of the send_controller_data
transport method which simply constructs one or more C2H PDUs from the
caller's mbuf chain.
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D44712
nvmf_transport.ko provides routines for managing NVMeoF queue pairs
and capsules. It provides a glue layer between transports (such as
TCP or RDMA) and an NVMeoF host (initiator) and controller (target).
Unlike the synchronous API exposed to the host and controller by
libnvmf, the kernel's transport layer uses an asynchronous API built
on callbacks. Upper layers provide callbacks on queue pairs that are
invoked for transport errors (error_cb) or anytime a capsule is
received (receive_cb).
Data transfers for a command are usually associated with a callback
that is invoked once a transfer has finished either due to an error
or successful completion.
For an upper layer that is a host, command capsules are allocated and
populated with an NVMe SQE by calling nvmf_allocate_command. A data
buffer (described by a struct memdesc) can be associated with a
command capsule before it is transmitted via nvmf_capsule_append_data.
This function accepts a direction (send vs receive) as well as the
data transfer callback. The host then transmits the command via
nvmf_transmit_capsule. The host must ensure that the data buffer
described by the 'struct memdesc' remains valid until the data
transfer callback is called. The queue pair's receive_cb callback
should match received response capsules up with previously transmitted
commands.
For the controller, incoming commands are received via the queue
pair's receive_cb callback. nvmf_receive_controller_data is used to
retrieve any data from a command (e.g. the data for a WRITE command).
It can be called multiple times to split the data transfer into
smaller sizes. This function accepts an I/O completion callback that
is invoked once the data transfer has completed.
nvmf_send_controller_data is used to send data to a remote host in
response to a command. In this case a callback function is not used
but the status is returned synchronously. Finally, the controller can
allocate a response capsule via nvmf_allocate_response populated with
a supplied CQE and send the response via nvmf_transmit_capsule.
Reviewed by: imp
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D44711
This contain the hdmi code and the aperture code like in linux.
Differential Revision: https://reviews.freebsd.org/D44925
Reviewed by: bz
Obtained from: drm-kmod
Sponsored by: Beckhoff Automation GmbH & Co. KG
In order to have a proper linuxkpi_video kmod, move the module declaration
to a new file as linuxkpi_video will also include linux_hdmi.c
Differential Revision: https://reviews.freebsd.org/D44926
Reviewed by: bz, emaste, wulf
Sponsored by: Beckhoff Automation GmbH & Co. KG
The unit.* code is largely obsolete and imposes limits that are no
longer needed nowadays.
- Capping the maximum allowed soundcards in a given machine. By default,
the limit is 512 (snd_max_u() in unit.c), and the maximum possible is
2048 (SND_UNIT_UMAX in unit.h). It can also be tuned through the
hw.snd.maxunit loader(8) tunable. Even though these limits are large
enough that they should never cause problems, there is no need for
this limit to exist in the first place.
- Capping the available device/channel types. By default, this is 32
(snd_max_d() in unit.c). However, these types are pre-defined in
pcm/sound.h (see SND_DEV_*), so the cap is unnecessary when we know
that their number is constant.
- Capping the number of channels per-device. By default, the limit 1024
(snd_max_c() in unit.c). This is probably the most problematic of the
limits mentioned, because this limit can never be reached, as the
maximum is hard-capped at either hw.snd.maxautovchans (16 by default),
or SND_MAXHWCHAN and SND_MAXVCHANS.
These limtits are encoded in masks (see SND_U_MASK, SND_D_MASK,
SND_C_MASK in unit.h) and are used to construct a bitfield of the form
[dsp_unit, type, channel_unit] in snd_mkunit() which is assigned to
pcm_channel->unit.
This patch gets rid of everything unit.*-related and makes a slightly
different use of the "unit" field to only contain the channel unit
number. The channel type is stored in a new pcm_channel->type field, and
the DSP unit number need not be stored at all, since we can fetch it
from device_get_unit(pcm_channel->dev). This change has the effect that
we no longer need to impose caps on the number of soundcards,
device/channel types and per-device channels. As a result the code is
noticeably simplified and more readable.
Apart from the fact that the hw.snd.maxunit loader(8) tunable is also
retired as a side-effect of this patch, sound(4)'s behavior remains the
same.
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Reviewed by: dev_submerge.ch
Differential Revision: https://reviews.freebsd.org/D44912
