In order to provide a clearer, more symmetric API for pinning and
unpinning DMA pages. This way, pin_user_pages*() calls match up with
unpin_user_pages*() calls, and the API is a lot closer to being
self-explanatory.
Link: http://lkml.kernel.org/r/20200107224558.2362728-23-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Björn Töpel <bjorn.topel@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Leon Romanovsky <leonro@mellanox.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert infiniband to use the new pin_user_pages*() calls.
Also, revert earlier changes to Infiniband ODP that had it using
put_user_page(). ODP is "Case 3" in
Documentation/core-api/pin_user_pages.rst, which is to say, normal
get_user_pages() and put_page() is the API to use there.
The new pin_user_pages*() calls replace corresponding get_user_pages*()
calls, and set the FOLL_PIN flag. The FOLL_PIN flag requires that the
caller must return the pages via put_user_page*() calls, but infiniband
was already doing that as part of an earlier commit.
Link: http://lkml.kernel.org/r/20200107224558.2362728-14-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Björn Töpel <bjorn.topel@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Leon Romanovsky <leonro@mellanox.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes, in particular in the
context in which this code is being used.
So, replace the following form:
sizeof(*pkt) + sizeof(pkt->addr[0])*n
with:
struct_size(pkt, addr, n)
Also, notice that variable size is unnecessary, hence it is removed.
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
For infiniband code that retains pages via get_user_pages*(), release
those pages via the new put_user_page(), or put_user_pages*(), instead of
put_page()
This is a tiny part of the second step of fixing the problem described in
[1]. The steps are:
1) Provide put_user_page*() routines, intended to be used for releasing
pages that were pinned via get_user_pages*().
2) Convert all of the call sites for get_user_pages*(), to invoke
put_user_page*(), instead of put_page(). This involves dozens of call
sites, and will take some time.
3) After (2) is complete, use get_user_pages*() and put_user_page*() to
implement tracking of these pages. This tracking will be separate from
the existing struct page refcounting.
4) Use the tracking and identification of these pages, to implement
special handling (especially in writeback paths) when the pages are
backed by a filesystem. Again, [1] provides details as to why that is
desirable.
[1] https://lwn.net/Articles/753027/ : "The Trouble with get_user_pages()"
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Jérôme Glisse <jglisse@redhat.com>
Acked-by: Jason Gunthorpe <jgg@mellanox.com>
Tested-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Use the new FOLL_LONGTERM to get_user_pages_fast() to protect against FS
DAX pages being mapped.
Link: http://lkml.kernel.org/r/20190328084422.29911-7-ira.weiny@intel.com
Link: http://lkml.kernel.org/r/20190317183438.2057-7-ira.weiny@intel.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Mike Marshall <hubcap@omnibond.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch avoids that a compiler warning is reported when building with
W=1.
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Fixes: 49c0e2414b ("IB/qib: Change SDMA progression mode depending on single- or multi-rail")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
QIB driver was added in 2010 with many BUG_ON(), most of them were cleaned
out after years of development and usages.
It looks like that it is safe now to remove rest of BUG_ONs.
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
To make the code clearer, use rb_entry() instead of container_of() to
deal with rbtree.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Acked-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Upstream checkpatch now requires this.
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Improve performance by changing the behavour of the driver when all
SDMA descriptors are in use, and the processes adding new descriptors
are single- or multi-rail.
For single-rail processes, the driver will block the call and finish
posting all SDMA descriptors onto the hardware queue before returning
back to PSM. Repeated kernel calls are slower than blocking.
For multi-rail processes, the driver will return to PSM as quick as
possible so PSM can feed packets to other rail. If all hardware
queues are full, PSM will buffer the remaining SDMA descriptors until
notified by interrupt that space is available.
This patch builds a red-black tree to track the number rails opened by
a particular PID. If the number is more than one, it is a multi-rail
PSM process, otherwise, it is a single-rail process.
Reviewed-by: Dean Luick <dean.luick@intel.com>
Reviewed-by: John A Gregor <john.a.gregor@intel.com>
Reviewed-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: CQ Tang <cq.tang@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
qib_user_sdma_queue_pkts() gets called with mmap_sem held for
writing. Except for get_user_pages() deep down in
qib_user_sdma_pin_pages() we don't seem to need mmap_sem at all. Even
more interestingly the function qib_user_sdma_queue_pkts() (and also
qib_user_sdma_coalesce() called somewhat later) call copy_from_user()
which can hit a page fault and we deadlock on trying to get mmap_sem
when handling that fault.
So just make qib_user_sdma_pin_pages() use get_user_pages_fast() and
leave mmap_sem locking for mm.
This deadlock has actually been observed in the wild when the node
is under memory pressure.
Cc: <stable@vger.kernel.org>
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Roland Dreier <roland@purestorage.com>
1. The code accepts chunks of messages, and splits the chunk into
packets when converting packets into sdma queue entries. Adjacent
packets will use user buffer pages smartly to avoid pinning the
same page multiple times.
2. Instead of discarding all the work when SDMA queue is full, the
work is saved in a pending queue. Whenever there are enough SDMA
queue free entries, pending queue is directly put onto SDMA queue.
3. An interrupt handler is used to progress this pending queue.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: CQ Tang <cq.tang@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
[ Fixed up sparse warnings. - Roland ]
Signed-off-by: Roland Dreier <roland@purestorage.com>
Reset the list pointers after freeing the SDMA packet list. This is
done to any potential double-free cases.
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Add a low-level IB driver for QLogic PCIe adapters.
Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
