Hi,
This applies cleanly to linux-next and mmotm, and also to linux.git if
linux-next's commit 20cac10710c9 ("mm/gup_benchmark: fix MAP_HUGETLB
case") is first applied there.
This provides tracking of dma-pinned pages. This is a prerequisite to
solving the larger problem of proper interactions between file-backed
pages, and [R]DMA activities, as discussed in [1], [2], [3], and in
a remarkable number of email threads since about 2017. :)
A new internal gup flag, FOLL_PIN is introduced, and thoroughly
documented in the last patch's Documentation/vm/pin_user_pages.rst.
I believe that this will provide a good starting point for doing the
layout lease work that Ira Weiny has been working on. That's because
these new wrapper functions provide a clean, constrained, systematically
named set of functionality that, again, is required in order to even
know if a page is "dma-pinned".
In contrast to earlier approaches, the page tracking can be
incrementally applied to the kernel call sites that, until now, have
been simply calling get_user_pages() ("gup"). In other words, opt-in by
changing from this:
get_user_pages() (sets FOLL_GET)
put_page()
to this:
pin_user_pages() (sets FOLL_PIN)
put_user_page()
Because there are interdependencies with FOLL_LONGTERM, a similar
conversion as for FOLL_PIN, was applied. The change was from this:
get_user_pages(FOLL_LONGTERM) (also sets FOLL_GET)
put_page()
to this:
pin_longterm_pages() (sets FOLL_PIN | FOLL_LONGTERM)
put_user_page()
============================================================
Patch summary:
* Patches 1-4: refactoring and preparatory cleanup, independent fixes
(Patch 4: V4L2-core bug fix (can be separately applied))
* Patch 5: introduce pin_user_pages(), FOLL_PIN, but no functional
changes yet
* Patches 6-11: Convert existing put_user_page() callers, to use the
new pin*()
* Patch 12: Activate tracking of FOLL_PIN pages.
* Patches 13-15: convert FOLL_LONGTERM callers
* Patches: 16-17: gup_benchmark and run_vmtests support
* Patch 18: enforce FOLL_LONGTERM as a gup-internal (only) flag
* Patch 19: Documentation/vm/pin_user_pages.rst
============================================================
Testing:
* I've done some overall kernel testing (LTP, and a few other goodies),
and some directed testing to exercise some of the changes. And as you
can see, gup_benchmark is enhanced to exercise this. Basically, I've been
able to runtime test the core get_user_pages() and pin_user_pages() and
related routines, but not so much on several of the call sites--but those
are generally just a couple of lines changed, each.
Not much of the kernel is actually using this, which on one hand
reduces risk quite a lot. But on the other hand, testing coverage
is low. So I'd love it if, in particular, the Infiniband and PowerPC
folks could do a smoke test of this series for me.
Also, my runtime testing for the call sites so far is very weak:
* io_uring: Some directed tests from liburing exercise this, and they pass.
* process_vm_access.c: A small directed test passes.
* gup_benchmark: the enhanced version hits the new gup.c code, and passes.
* infiniband (still only have crude "IB pingpong" working, on a
good day: it's not exercising my conversions at runtime...)
* VFIO: compiles (I'm vowing to set up a run time test soon, but it's
not ready just yet)
* powerpc: it compiles...
* drm/via: compiles...
* goldfish: compiles...
* net/xdp: compiles...
* media/v4l2: compiles...
============================================================
Next:
* Get the block/bio_vec sites converted to use pin_user_pages().
* Work with Ira and Dave Chinner to weave this together with the
layout lease stuff.
============================================================
[1] Some slow progress on get_user_pages() (Apr 2, 2019): https://lwn.net/Articles/784574/
[2] DMA and get_user_pages() (LPC: Dec 12, 2018): https://lwn.net/Articles/774411/
[3] The trouble with get_user_pages() (Apr 30, 2018): https://lwn.net/Articles/753027/
John Hubbard (19):
mm/gup: pass flags arg to __gup_device_* functions
mm/gup: factor out duplicate code from four routines
goldish_pipe: rename local pin_user_pages() routine
media/v4l2-core: set pages dirty upon releasing DMA buffers
mm/gup: introduce pin_user_pages*() and FOLL_PIN
goldish_pipe: convert to pin_user_pages() and put_user_page()
infiniband: set FOLL_PIN, FOLL_LONGTERM via pin_longterm_pages*()
mm/process_vm_access: set FOLL_PIN via pin_user_pages_remote()
drm/via: set FOLL_PIN via pin_user_pages_fast()
fs/io_uring: set FOLL_PIN via pin_user_pages()
net/xdp: set FOLL_PIN via pin_user_pages()
mm/gup: track FOLL_PIN pages
media/v4l2-core: pin_longterm_pages (FOLL_PIN) and put_user_page()
conversion
vfio, mm: pin_longterm_pages (FOLL_PIN) and put_user_page() conversion
powerpc: book3s64: convert to pin_longterm_pages() and put_user_page()
mm/gup_benchmark: support pin_user_pages() and related calls
selftests/vm: run_vmtests: invoke gup_benchmark with basic FOLL_PIN
coverage
mm/gup: remove support for gup(FOLL_LONGTERM)
Documentation/vm: add pin_user_pages.rst
Documentation/vm/index.rst | 1 +
Documentation/vm/pin_user_pages.rst | 213 +++++++
arch/powerpc/mm/book3s64/iommu_api.c | 15 +-
drivers/gpu/drm/via/via_dmablit.c | 2 +-
drivers/infiniband/core/umem.c | 5 +-
drivers/infiniband/core/umem_odp.c | 10 +-
drivers/infiniband/hw/hfi1/user_pages.c | 4 +-
drivers/infiniband/hw/mthca/mthca_memfree.c | 3 +-
drivers/infiniband/hw/qib/qib_user_pages.c | 8 +-
drivers/infiniband/hw/qib/qib_user_sdma.c | 2 +-
drivers/infiniband/hw/usnic/usnic_uiom.c | 9 +-
drivers/infiniband/sw/siw/siw_mem.c | 5 +-
drivers/media/v4l2-core/videobuf-dma-sg.c | 10 +-
drivers/platform/goldfish/goldfish_pipe.c | 35 +-
drivers/vfio/vfio_iommu_type1.c | 15 +-
fs/io_uring.c | 5 +-
include/linux/mm.h | 133 ++++-
include/linux/mmzone.h | 2 +
include/linux/page_ref.h | 10 +
mm/gup.c | 622 ++++++++++++++++----
mm/gup_benchmark.c | 81 ++-
mm/huge_memory.c | 32 +-
mm/hugetlb.c | 28 +-
mm/memremap.c | 4 +-
mm/process_vm_access.c | 28 +-
mm/vmstat.c | 2 +
net/xdp/xdp_umem.c | 4 +-
tools/testing/selftests/vm/gup_benchmark.c | 28 +-
tools/testing/selftests/vm/run_vmtests | 22 +
29 files changed, 1066 insertions(+), 272 deletions(-)
create mode 100644 Documentation/vm/pin_user_pages.rst
--
2.23.0
Greetings,
Find the attached mail very confidential. reply for more details
Thanks.
Peter Wong
----------------------------------------------------
This email was sent by the shareware version of Postman Professional.
Verify that in this scenario
------------------------ N2
| |
------ ------ N3 ----
| R1 | | R2 |------|H2|
------ ------ ----
| |
------------------------ N1
|
----
|H1|
----
where H1's default route goes through R1 and R1's default route goes
through R2 over N2, traceroute6 from H1 to H2 reports R2's address
on N2 and not N1.
Signed-off-by: Francesco Ruggeri <fruggeri(a)arista.com>
---
tools/testing/selftests/net/Makefile | 1 +
.../testing/selftests/net/icmp6_reply_addr.sh | 159 ++++++++++++++++++
2 files changed, 160 insertions(+)
create mode 100755 tools/testing/selftests/net/icmp6_reply_addr.sh
diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile
index 0bd6b23c97ef..daeaeb59d5ca 100644
--- a/tools/testing/selftests/net/Makefile
+++ b/tools/testing/selftests/net/Makefile
@@ -11,6 +11,7 @@ TEST_PROGS += udpgso_bench.sh fib_rule_tests.sh msg_zerocopy.sh psock_snd.sh
TEST_PROGS += udpgro_bench.sh udpgro.sh test_vxlan_under_vrf.sh reuseport_addr_any.sh
TEST_PROGS += test_vxlan_fdb_changelink.sh so_txtime.sh ipv6_flowlabel.sh
TEST_PROGS += tcp_fastopen_backup_key.sh fcnal-test.sh l2tp.sh
+TEST_PROGS += icmp6_reply_addr.sh
TEST_PROGS_EXTENDED := in_netns.sh
TEST_GEN_FILES = socket nettest
TEST_GEN_FILES += psock_fanout psock_tpacket msg_zerocopy reuseport_addr_any
diff --git a/tools/testing/selftests/net/icmp6_reply_addr.sh b/tools/testing/selftests/net/icmp6_reply_addr.sh
new file mode 100755
index 000000000000..551834cb9272
--- /dev/null
+++ b/tools/testing/selftests/net/icmp6_reply_addr.sh
@@ -0,0 +1,159 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Verify that in this scenario
+#
+# ------------------------ N2
+# | |
+# ------ ------ N3 ----
+# | R1 | | R2 |------|H2|
+# ------ ------ ----
+# | |
+# ------------------------ N1
+# |
+# ----
+# |H1|
+# ----
+#
+# where H1's default route goes through R1 and R1's default route goes
+# through R2 over N2, traceroute6 from H1 to H2 reports R2's address
+# on N2 and not N1.
+#
+# Addresses are assigned as follows:
+#
+# N1: 2000:101::/64
+# N2: 2000:102::/64
+# N3: 2000:103::/64
+#
+# R1's host part of address: 1
+# R2's host part of address: 2
+# H1's host part of address: 3
+# H2's host part of address: 4
+#
+# For example:
+# the IPv6 address of R1's interface on N2 is 2000:102::1/64
+
+####################################################################
+# helpers
+#
+# Interface on network <net> in node <node> is called <node><net>
+#
+
+node()
+{
+ host=$1
+ shift
+ ip netns exec ${host} $*
+}
+
+create_nodes()
+{
+ for n in $*; do
+ ip netns add $n
+ node $n ip link set lo up
+ done
+}
+
+delete_nodes()
+{
+ for n in $*; do
+ ip netns del $n
+ done
+}
+
+create_veth_net()
+{
+ net=$1
+ h1=$2
+ h2=$3
+
+ ip link add ${h1}${net} type veth peer name ${h2}${net}
+ ip link set ${h1}${net} netns ${h1}
+ node ${h1} ip link set ${h1}${net} up
+ ip link set ${h2}${net} netns ${h2}
+ node ${h2} ip link set ${h2}${net} up
+}
+
+create_macvlan_net()
+{
+ net=$1
+ shift
+ nodes=$*
+
+ ip link add ${net} type dummy
+ ip link set ${net} up
+
+ for n in ${nodes}; do
+ ip link add link ${net} dev ${n}${net} type macvlan mode bridge
+ ip link set ${n}${net} netns $n
+ node ${n} ip link set ${n}${net} up
+ done
+}
+
+delete_macvlan_nets()
+{
+ nets=$*
+
+ for n in ${nets}; do
+ ip link del ${n}
+ done
+}
+
+# end helpers
+####################################################################
+
+if [ "$(id -u)" -ne 0 ]; then
+ echo "SKIP: Need root privileges"
+ exit 0
+fi
+
+if [ ! -x "$(command -v traceroute6)" ]; then
+ echo "SKIP: Could not run test without traceroute6"
+ exit 0
+fi
+
+create_nodes host1 host2 rtr1 rtr2
+
+create_macvlan_net net1 host1 rtr1 rtr2
+create_veth_net net2 rtr1 rtr2
+create_veth_net net3 rtr2 host2
+
+# Configure interfaces and routes in host1
+node host1 ip -6 addr add 2000:101::3/64 dev host1net1
+node host1 ip -6 route add default via 2000:101::1
+
+# Configure interfaces and routes in rtr1
+node rtr1 ip -6 addr add 2000:101::1/64 dev rtr1net1
+node rtr1 ip -6 addr add 2000:102::1/64 dev rtr1net2
+node rtr1 ip -6 route add default via 2000:102::2
+node rtr1 sysctl net.ipv6.conf.all.forwarding=1 >/dev/null
+
+# Configure interfaces and routes in rtr2
+node rtr2 ip -6 addr add 2000:101::2/64 dev rtr2net1
+node rtr2 ip -6 addr add 2000:102::2/64 dev rtr2net2
+node rtr2 ip -6 addr add 2000:103::2/64 dev rtr2net3
+node rtr2 sysctl net.ipv6.conf.all.forwarding=1 >/dev/null
+
+# Configure interfaces and routes in host2
+node host2 ip -6 addr add 2000:103::4/64 dev host2net3
+node host2 ip -6 route add default via 2000:103::2
+
+# Ping host2 from host1
+echo "Priming the network"
+node host1 ping6 -c5 2000:103::4 >/dev/null
+
+# Traceroute host2 from host1
+echo "Running traceroute6"
+if node host1 traceroute6 2000:103::4 | grep -q 2000:102::2; then
+ ret=0
+ echo "Found 2000:102::2. Test passed."
+else
+ ret=1
+ echo "Did not find 2000:102::2. Test failed."
+fi
+
+delete_macvlan_nets net1
+delete_nodes host1 host2 rtr1 rtr2
+
+exit ${ret}
+
--
2.19.1