From: enjoymindful@gmail.com (Real Name)
To: kernelnewbies@lists.kernelnewbies.org
Subject: View device <=> IOMMU mapping table
Date: Wed, 9 Jul 2014 23:08:17 +0800 [thread overview]
Message-ID: <20140709150817.GA16438@name> (raw)
In-Reply-To: <1404907938.95659.YahooMailNeo@web162501.mail.bf1.yahoo.com>
On Wed, Jul 09, 2014 at 05:12:18AM -0700, Ahmed A wrote:
> Hello,
> I know the b:d.f? of my device.? However, I am not able to tell if this specific device is mapped to the right IOMMU.? In my specific system there are two IOMMU, right?
http://www.intel.com/content/www/us/en/intelligent-systems/intel-technology/vt-directed-io-spec.html
Why you think there are two IOMMU? Just because there are two socket?
If there is north bridge, the IOMMU is in the north bridge, not the
CPU/socket.
/proc/iomem list the bus space address range of the PCIe device. The bus space
to memory space mapping is dynamic. I insrumented the mlx4 infiniband
driver to trace the DMA mapping (on a 2-sockets x86_64 server).
[root at localhost mlx4]# lspci -vs 07:00.0
07:00.0 Network controller: Mellanox Technologies MT27500 Family [ConnectX-3]
Subsystem: Mellanox Technologies Device 0050
Physical Slot: 2
Flags: bus master, fast devsel, latency 0, IRQ 26
Memory at f7f00000 (64-bit, non-prefetchable) [size=1M]
Memory at f6000000 (64-bit, prefetchable) [size=8M]
Capabilities: [40] Power Management version 3
Capabilities: [48] Vital Product Data
Capabilities: [9c] MSI-X: Enable+ Count=128 Masked-
Capabilities: [60] Express Endpoint, MSI 00
Capabilities: [100] Alternative Routing-ID Interpretation (ARI)
Capabilities: [148] Device Serial Number 00-02-c9-03-00-b3-c7-c0
Capabilities: [108] Single Root I/O Virtualization (SR-IOV)
Capabilities: [154] Advanced Error Reporting
Capabilities: [18c] #19
Kernel driver in use: mlx4_core
[root at localhost mlx4]#
[root at localhost mlx4]# dmesg
[root at localhost mlx4]# ibv_rc_pingpong
local address: LID 0x0002, QPN 0x000054, PSN 0x454e1a, GID ::
remote address: LID 0x0001, QPN 0x000054, PSN 0x6e4596, GID ::
8192000 bytes in 0.00 seconds = 13799.96 Mbit/sec
1000 iters in 0.00 seconds = 4.75 usec/iter
[root at localhost mlx4]# dmesg
[ 5474.650073] vma = ffff8804164460b8, vma->vm_start = 00002af33ba39000, pfn = 1007753, pva = 00000000f6089000, kva = ffff8800f6089000, n = 1
[ 5474.706424] vma = ffff880416446730, vma->vm_start = 00002af33ba3a000, pfn = 1007753, pva = 00000000f6089000, kva = ffff8800f6089000, n = 2
[root at localhost ~]#
As you see, pva (000f6089000) belong to this bus space address "Memory at f6000000 (64-bit, prefetchable) [size=8M]".
Hope this can be help.
>? If so, I am not sure how I can get the mapping info from the output of /proc/iomem.
prev parent reply other threads:[~2014-07-09 15:08 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-07-09 4:33 View device <=> IOMMU mapping table Ahmed A
2014-07-09 8:18 ` Real Name
2014-07-09 12:12 ` Ahmed A
2014-07-09 15:08 ` Real Name [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20140709150817.GA16438@name \
--to=enjoymindful@gmail.com \
--cc=kernelnewbies@lists.kernelnewbies.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.