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From: Mike Rapoport <rppt@linux.vnet.ibm.com>
To: Jonathan Corbet <corbet@lwn.net>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>,
	Richard Henderson <rth@twiddle.net>,
	Ivan Kokshaysky <ink@jurassic.park.msu.ru>,
	Matt Turner <mattst88@gmail.com>, Tony Luck <tony.luck@intel.com>,
	Fenghua Yu <fenghua.yu@intel.com>,
	Ralf Baechle <ralf@linux-mips.org>,
	James Hogan <jhogan@kernel.org>,
	Michael Ellerman <mpe@ellerman.id.au>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
	kasan-dev@googlegroups.com, linux-alpha@vger.kernel.org,
	linux-ia64@vger.kernel.org, linux-mips@linux-mips.org,
	linuxppc-dev@lists.ozlabs.org, linux-fsdevel@vger.kernel.org,
	linux-mm@kvack.org, Mike Rapoport <rppt@linux.vnet.ibm.com>
Subject: [PATCH 27/32] docs/vm: userfaultfd.txt: convert to ReST format
Date: Wed, 21 Mar 2018 21:22:43 +0200	[thread overview]
Message-ID: <1521660168-14372-28-git-send-email-rppt@linux.vnet.ibm.com> (raw)
In-Reply-To: <1521660168-14372-1-git-send-email-rppt@linux.vnet.ibm.com>

Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
---
 Documentation/vm/userfaultfd.txt | 66 ++++++++++++++++++++++++----------------
 1 file changed, 39 insertions(+), 27 deletions(-)

diff --git a/Documentation/vm/userfaultfd.txt b/Documentation/vm/userfaultfd.txt
index bb2f945..5048cf6 100644
--- a/Documentation/vm/userfaultfd.txt
+++ b/Documentation/vm/userfaultfd.txt
@@ -1,6 +1,11 @@
-= Userfaultfd =
+.. _userfaultfd:
 
-== Objective ==
+===========
+Userfaultfd
+===========
+
+Objective
+=========
 
 Userfaults allow the implementation of on-demand paging from userland
 and more generally they allow userland to take control of various
@@ -9,7 +14,8 @@ memory page faults, something otherwise only the kernel code could do.
 For example userfaults allows a proper and more optimal implementation
 of the PROT_NONE+SIGSEGV trick.
 
-== Design ==
+Design
+======
 
 Userfaults are delivered and resolved through the userfaultfd syscall.
 
@@ -41,7 +47,8 @@ different processes without them being aware about what is going on
 themselves on the same region the manager is already tracking, which
 is a corner case that would currently return -EBUSY).
 
-== API ==
+API
+===
 
 When first opened the userfaultfd must be enabled invoking the
 UFFDIO_API ioctl specifying a uffdio_api.api value set to UFFD_API (or
@@ -101,7 +108,8 @@ UFFDIO_COPY. They're atomic as in guaranteeing that nothing can see an
 half copied page since it'll keep userfaulting until the copy has
 finished.
 
-== QEMU/KVM ==
+QEMU/KVM
+========
 
 QEMU/KVM is using the userfaultfd syscall to implement postcopy live
 migration. Postcopy live migration is one form of memory
@@ -163,7 +171,8 @@ sending the same page twice (in case the userfault is read by the
 postcopy thread just before UFFDIO_COPY|ZEROPAGE runs in the migration
 thread).
 
-== Non-cooperative userfaultfd ==
+Non-cooperative userfaultfd
+===========================
 
 When the userfaultfd is monitored by an external manager, the manager
 must be able to track changes in the process virtual memory
@@ -172,27 +181,30 @@ the same read(2) protocol as for the page fault notifications. The
 manager has to explicitly enable these events by setting appropriate
 bits in uffdio_api.features passed to UFFDIO_API ioctl:
 
-UFFD_FEATURE_EVENT_FORK - enable userfaultfd hooks for fork(). When
-this feature is enabled, the userfaultfd context of the parent process
-is duplicated into the newly created process. The manager receives
-UFFD_EVENT_FORK with file descriptor of the new userfaultfd context in
-the uffd_msg.fork.
-
-UFFD_FEATURE_EVENT_REMAP - enable notifications about mremap()
-calls. When the non-cooperative process moves a virtual memory area to
-a different location, the manager will receive UFFD_EVENT_REMAP. The
-uffd_msg.remap will contain the old and new addresses of the area and
-its original length.
-
-UFFD_FEATURE_EVENT_REMOVE - enable notifications about
-madvise(MADV_REMOVE) and madvise(MADV_DONTNEED) calls. The event
-UFFD_EVENT_REMOVE will be generated upon these calls to madvise. The
-uffd_msg.remove will contain start and end addresses of the removed
-area.
-
-UFFD_FEATURE_EVENT_UNMAP - enable notifications about memory
-unmapping. The manager will get UFFD_EVENT_UNMAP with uffd_msg.remove
-containing start and end addresses of the unmapped area.
+UFFD_FEATURE_EVENT_FORK
+	enable userfaultfd hooks for fork(). When this feature is
+	enabled, the userfaultfd context of the parent process is
+	duplicated into the newly created process. The manager
+	receives UFFD_EVENT_FORK with file descriptor of the new
+	userfaultfd context in the uffd_msg.fork.
+
+UFFD_FEATURE_EVENT_REMAP
+	enable notifications about mremap() calls. When the
+	non-cooperative process moves a virtual memory area to a
+	different location, the manager will receive
+	UFFD_EVENT_REMAP. The uffd_msg.remap will contain the old and
+	new addresses of the area and its original length.
+
+UFFD_FEATURE_EVENT_REMOVE
+	enable notifications about madvise(MADV_REMOVE) and
+	madvise(MADV_DONTNEED) calls. The event UFFD_EVENT_REMOVE will
+	be generated upon these calls to madvise. The uffd_msg.remove
+	will contain start and end addresses of the removed area.
+
+UFFD_FEATURE_EVENT_UNMAP
+	enable notifications about memory unmapping. The manager will
+	get UFFD_EVENT_UNMAP with uffd_msg.remove containing start and
+	end addresses of the unmapped area.
 
 Although the UFFD_FEATURE_EVENT_REMOVE and UFFD_FEATURE_EVENT_UNMAP
 are pretty similar, they quite differ in the action expected from the
-- 
2.7.4

  parent reply	other threads:[~2018-03-21 19:22 UTC|newest]

Thread overview: 41+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-03-21 19:22 [PATCH 00/32] docs/vm: convert to ReST format Mike Rapoport
2018-03-21 19:22 ` [PATCH 01/32] docs/vm: active_mm.txt " Mike Rapoport
2018-03-21 19:22 ` [PATCH 02/32] docs/vm: balance: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 03/32] docs/vm: cleancache.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 04/32] docs/vm: frontswap.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 05/32] docs/vm: highmem.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 06/32] docs/vm: hmm.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 07/32] docs/vm: hugetlbpage.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 08/32] docs/vm: hugetlbfs_reserv.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 09/32] docs/vm: hwpoison.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 10/32] docs/vm: idle_page_tracking.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 11/32] docs/vm: ksm.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 12/32] docs/vm: mmu_notifier.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 13/32] docs/vm: numa_memory_policy.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 14/32] docs/vm: overcommit-accounting: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 15/32] docs/vm: page_frags " Mike Rapoport
2018-03-21 19:22 ` [PATCH 16/32] docs/vm: numa: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 17/32] docs/vm: pagemap.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 18/32] docs/vm: page_migration: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 19/32] docs/vm: page_owner: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 20/32] docs/vm: remap_file_pages.txt: conert " Mike Rapoport
2018-03-21 19:22 ` [PATCH 21/32] docs/vm: slub.txt: convert " Mike Rapoport
2018-03-21 19:22 ` [PATCH 22/32] docs/vm: soft-dirty.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 23/32] docs/vm: split_page_table_lock: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 24/32] docs/vm: swap_numa.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 25/32] docs/vm: transhuge.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 26/32] docs/vm: unevictable-lru.txt: " Mike Rapoport
2018-03-21 19:22 ` Mike Rapoport [this message]
2018-03-21 19:22 ` [PATCH 28/32] docs/vm: z3fold.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 29/32] docs/vm: zsmalloc.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 30/32] docs/vm: zswap.txt: " Mike Rapoport
2018-03-21 19:22 ` [PATCH 31/32] docs/vm: rename documentation files to .rst Mike Rapoport
2018-03-21 19:22 ` [PATCH 32/32] docs/vm: add index.rst and link MM documentation to top level index Mike Rapoport
2018-03-29 21:46 ` [PATCH 00/32] docs/vm: convert to ReST format Jonathan Corbet
2018-04-01  6:38   ` Mike Rapoport
2018-04-10 10:23     ` Mike Rapoport
2018-04-13 19:55     ` Jonathan Corbet
2018-04-13 20:21       ` Matthew Wilcox
2018-04-15 17:29         ` Mike Rapoport
2018-04-15 17:36       ` Mike Rapoport
2018-04-16 20:35         ` Jonathan Corbet

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