opnsense-src/sys
Kenneth D. Merry 264610a86e mpr, mps: Establish busdma boundaries for memory pools
Most all of the memory used by the cards in the mpr(4) and mps(4)
drivers is required, according to the specs and Broadcom developers,
to be within a 4GB segment of memory.

This includes:

System Request Message Frames pool
Reply Free Queues pool
ReplyDescriptorPost Queues pool
Chain Segments pool
Sense Buffers pool
SystemReply message pool

We got a bug report from Dwight Engen, who ran into data corruption
in the BAE port of FreeBSD:

> We have a port of the FreeBSD mpr driver to our kernel and recently
> I found an issue under heavy load where a DMA may go to the wrong
> address. The test system is a Supermicro X10SRH-CLN4F with the
> onboard SAS3008 controller setup with 2 enterprise Micron SSDs in
> RAID 0 (striped). I have debugged the issue and narrowed down that
> the errant DMA is one that has a segment that crosses a 4GB
> physical boundary.  There are more details I can provide if you'd
> like, but with the attached patch in place I can no longer
> re-create the issue.

> I'm not sure if this is a known limit of the card (have not found a
> datasheet/programming docs for the chip) or our system is just
> doing something a bit different. Any helpful info or insight would
> be welcome.

> Anyway, just thought this might be helpful info if you want to
> apply a similar fix to FreeBSD. You can ignore/discard the commit
> message as it is my internal commit (blkio is our own tool we use
> to write/read every block of a device with CRC verification which
> is how I found the problem).

The commit message was:

> [PATCH 8/9] mpr: fix memory corrupting DMA when sg segment crosses
> 4GB boundary

> Test case was two SSD's in RAID 0 (stripe). The logical disk was
> then partitioned into two partitions. One partition had lots of
> filesystem I/O and the other was initially filled using blkio with
> CRCable data and then read back with blkio CRC verify in a loop.
> Eventually blkio would report a bad CRC block because the physical
> page being read-ahead into didn't contain the right data. If the
> physical address in the arq/segs was for example 0x500003000 the
> data would actually be DMAed to 0x400003000.

The original patch was against mpr(4) before busdma templates were
introduced, and only affected the buffer pool (sc->buffer_dmat) in
the mpr(4) driver. After some discussion with Dwight and the
LSI/Broadcom developers and looking through the driver, it looks
like most of the queues in the driver are ok, because they limit
the memory used to memory below 4GB. The buffer queue and the chain
frames seem to be the exceptions.

This is pretty much the same between the mpr(4) and mps(4) drivers.

So, apply a 4GB boundary limitation for the buffer and chain frame pools
in the mpr(4) and mps(4) drivers.

Reported by:	Dwight Engen <dwight.engen@gmail.com>
Reviewed by:	imp
Obtained from:	Dwight Engen <dwight.engen@gmail.com>
Differential Revision:	<https://reviews.freebsd.org/D43008>
2023-12-14 15:05:17 -05:00
..
amd64 vmm: implement VM_CAP_MASK_HWINTR on AMD CPUs 2023-12-07 15:11:04 -08:00
arm arm: Disable the VFP during boot 2023-12-11 09:08:49 -05:00
arm64 busdma: tidy bus_dma_run_filter() functions 2023-12-06 19:11:39 -04:00
bsm timerfd: Move implementation from linux compat to sys/kern 2023-08-24 14:28:56 -06:00
cam cam: Make cam.h self-contained for userland 2023-11-30 18:32:39 -07:00
cddl sys: Automated cleanup of cdefs and other formatting 2023-11-26 22:24:00 -07:00
compat linuxkpi: Add struct kset support in <linux/kobject.h> 2023-12-13 19:57:52 +01:00
conf Revert "Don't try and run kldxref for arm kernels" 2023-12-14 18:27:09 +00:00
contrib qat: Update firmware for 4xxx devices to version 1.1.20 2023-12-13 09:47:37 -05:00
crypto ossl: Remove a stray __FBSDID("$FreeBSD$") 2023-12-04 12:29:30 -05:00
ddb sys: Automated cleanup of cdefs and other formatting 2023-11-26 22:24:00 -07:00
dev mpr, mps: Establish busdma boundaries for memory pools 2023-12-14 15:05:17 -05:00
dts sys: Remove $FreeBSD$: one-line bare tag 2023-08-16 11:55:17 -06:00
fs nfsclient: Propagate copyin() errors from nfsm_uiombuf() 2023-12-12 14:05:24 -05:00
gdb sys: Automated cleanup of cdefs and other formatting 2023-11-26 22:24:00 -07:00
geom sys: Automated cleanup of cdefs and other formatting 2023-11-26 22:24:00 -07:00
gnu sys: Automated cleanup of cdefs and other formatting 2023-11-26 22:24:00 -07:00
i386 x86: Support multiple PCI MCFG regions 2023-11-29 10:32:39 -08:00
isa sys: Automated cleanup of cdefs and other formatting 2023-11-26 22:24:00 -07:00
kern tty: Avoid a kernel memory discloure via kern.ttys 2023-12-11 09:19:09 -05:00
kgssapi sys: Automated cleanup of cdefs and other formatting 2023-11-26 22:24:00 -07:00
libkern sys: Automated cleanup of cdefs and other formatting 2023-11-26 22:24:00 -07:00
modules Revert "Don't try and run kldxref for arm kernels" 2023-12-14 18:27:09 +00:00
net if_tun: check device name 2023-12-12 06:02:11 +02:00
net80211 net80211: move net_epoch into net80211 2023-12-01 00:46:10 +00:00
netgraph sockets: don't malloc/free sockaddr memory on getpeername/getsockname 2023-11-30 08:31:10 -08:00
netinet tcp: tcp: allow SOL_SOCKET-level socket options via sysctl interface 2023-12-09 13:03:51 +01:00
netinet6 sockets: don't malloc/free sockaddr memory on getpeername/getsockname 2023-11-30 08:31:10 -08:00
netipsec sys: Automated cleanup of cdefs and other formatting 2023-11-26 22:24:00 -07:00
netlink netlink: fix snl_writer and linear_buffer re-allocation logic 2023-12-12 21:49:14 +01:00
netpfil pf: fix memory leak on rule add parse failure 2023-12-11 20:53:00 +01:00
netsmb sys: Automated cleanup of cdefs and other formatting 2023-11-26 22:24:00 -07:00
nfs sys: Automated cleanup of cdefs and other formatting 2023-11-26 22:24:00 -07:00
nfsclient sys: Remove ancient SCCS tags. 2023-11-26 22:23:30 -07:00
nfsserver sys: Remove ancient SCCS tags. 2023-11-26 22:23:30 -07:00
nlm sys: Automated cleanup of cdefs and other formatting 2023-11-26 22:24:00 -07:00
ofed ofed: garbage collect now unused sdp_sockaddr() 2023-11-30 21:50:16 -08:00
opencrypto sys: Automated cleanup of cdefs and other formatting 2023-11-26 22:24:00 -07:00
powerpc busdma: tidy bus_dma_run_filter() functions 2023-12-06 19:11:39 -04:00
riscv busdma: tidy bus_dma_run_filter() functions 2023-12-06 19:11:39 -04:00
rpc sockets: don't malloc/free sockaddr memory on getpeername/getsockname 2023-11-30 08:31:10 -08:00
security sys: Automated cleanup of cdefs and other formatting 2023-11-26 22:24:00 -07:00
sys libc: expose execvpe for Linux compat 2023-12-11 19:24:53 +00:00
teken teken: fix style in teken_wcwidth.h 2023-10-13 08:14:57 +03:00
tests sys: Automated cleanup of cdefs and other formatting 2023-11-26 22:24:00 -07:00
tools makesyscalls: add COMPAT14 support 2023-12-01 20:00:39 +00:00
ufs Increase UFS/FFS maximum link count from 32767 to 65530. 2023-12-03 12:40:29 -08:00
vm Remove never implemented sbrk and sstk syscalls 2023-12-04 20:36:08 +00:00
x86 busdma: tidy bus_dma_run_filter() functions 2023-12-06 19:11:39 -04:00
xdr sys: Automated cleanup of cdefs and other formatting 2023-11-26 22:24:00 -07:00
xen xen: remove xen_domain_type enum/variable 2023-11-28 13:40:19 +01:00
Makefile sys: Remove $FreeBSD$: one-line sh pattern 2023-08-16 11:54:58 -06:00
README.md sys/README.md: Add a section for documentation 2023-08-03 11:07:41 -03:00

FreeBSD Kernel Source:

This directory contains the source files and build glue that make up the FreeBSD kernel and its modules, including both original and contributed software.

Kernel configuration files are located in the conf/ subdirectory of each architecture. GENERIC is the configuration used in release builds. NOTES contains documentation of all possible entries. LINT is a compile-only configuration used to maximize build coverage and detect regressions.

Documentation:

Source code documentation is maintained in a set of man pages, under section 9. These pages are located in share/man/man9, from the top-level of the src tree. Consult intro(9) for an overview of existing pages.

Some additional high-level documentation of the kernel is maintained in the Architecture Handbook.

Source Roadmap:

Directory Description
amd64 AMD64 (64-bit x86) architecture support
arm 32-bit ARM architecture support
arm64 64-bit ARM (AArch64) architecture support
cam Common Access Method storage subsystem - cam(4) and ctl(4)
cddl CDDL-licensed optional sources such as DTrace
conf kernel build glue
compat Linux compatibility layer, FreeBSD 32-bit compatibility
contrib 3rd-party imported software such as OpenZFS
crypto crypto drivers
ddb interactive kernel debugger - ddb(4)
fs most filesystems, excluding UFS, NFS, and ZFS
dev device drivers and other arch independent code
gdb kernel remote GDB stub - gdb(4)
geom GEOM framework - geom(4)
i386 i386 (32-bit x86) architecture support
kern main part of the kernel
libkern libc-like and other support functions for kernel use
modules kernel module infrastructure
net core networking code
net80211 wireless networking (IEEE 802.11) - net80211(4)
netgraph graph-based networking subsystem - netgraph(4)
netinet IPv4 protocol implementation - inet(4)
netinet6 IPv6 protocol implementation - inet6(4)
netipsec IPsec protocol implementation - ipsec(4)
netpfil packet filters - ipfw(4), pf(4), and ipfilter(4)
opencrypto OpenCrypto framework - crypto(7)
powerpc PowerPC/POWER (32 and 64-bit) architecture support
riscv 64-bit RISC-V architecture support
security security facilities - audit(4) and mac(4)
sys kernel headers
tests kernel unit tests
ufs Unix File System - ffs(7)
vm virtual memory system
x86 code shared by AMD64 and i386 architectures