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From: Changbin Du <changbin.du@gmail.com>
To: corbet@lwn.net, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de
Cc: x86@kernel.org, linux-doc@vger.kernel.org,
	linux-kernel@vger.kernel.org, Changbin Du <changbin.du@gmail.com>,
	Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Subject: [PATCH v4 12/27] Documentation: x86: convert protection-keys.txt to reST
Date: Wed,  8 May 2019 23:21:26 +0800	[thread overview]
Message-ID: <20190508152141.8740-13-changbin.du@gmail.com> (raw)
In-Reply-To: <20190508152141.8740-1-changbin.du@gmail.com>

This converts the plain text documentation to reStructuredText format and
add it to Sphinx TOC tree. No essential content change.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
---
 Documentation/x86/index.rst                   |  1 +
 ...rotection-keys.txt => protection-keys.rst} | 33 ++++++++++++-------
 2 files changed, 22 insertions(+), 12 deletions(-)
 rename Documentation/x86/{protection-keys.txt => protection-keys.rst} (83%)

diff --git a/Documentation/x86/index.rst b/Documentation/x86/index.rst
index f7012e4afacd..e2c0db9fcd4e 100644
--- a/Documentation/x86/index.rst
+++ b/Documentation/x86/index.rst
@@ -18,3 +18,4 @@ x86-specific Documentation
    tlb
    mtrr
    pat
+   protection-keys
diff --git a/Documentation/x86/protection-keys.txt b/Documentation/x86/protection-keys.rst
similarity index 83%
rename from Documentation/x86/protection-keys.txt
rename to Documentation/x86/protection-keys.rst
index ecb0d2dadfb7..49d9833af871 100644
--- a/Documentation/x86/protection-keys.txt
+++ b/Documentation/x86/protection-keys.rst
@@ -1,3 +1,9 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+======================
+Memory Protection Keys
+======================
+
 Memory Protection Keys for Userspace (PKU aka PKEYs) is a feature
 which is found on Intel's Skylake "Scalable Processor" Server CPUs.
 It will be avalable in future non-server parts.
@@ -23,9 +29,10 @@ even though there is theoretically space in the PAE PTEs.  These
 permissions are enforced on data access only and have no effect on
 instruction fetches.
 
-=========================== Syscalls ===========================
+Syscalls
+========
 
-There are 3 system calls which directly interact with pkeys:
+There are 3 system calls which directly interact with pkeys::
 
 	int pkey_alloc(unsigned long flags, unsigned long init_access_rights)
 	int pkey_free(int pkey);
@@ -37,6 +44,7 @@ pkey_alloc().  An application calls the WRPKRU instruction
 directly in order to change access permissions to memory covered
 with a key.  In this example WRPKRU is wrapped by a C function
 called pkey_set().
+::
 
 	int real_prot = PROT_READ|PROT_WRITE;
 	pkey = pkey_alloc(0, PKEY_DISABLE_WRITE);
@@ -45,43 +53,44 @@ called pkey_set().
 	... application runs here
 
 Now, if the application needs to update the data at 'ptr', it can
-gain access, do the update, then remove its write access:
+gain access, do the update, then remove its write access::
 
 	pkey_set(pkey, 0); // clear PKEY_DISABLE_WRITE
 	*ptr = foo; // assign something
 	pkey_set(pkey, PKEY_DISABLE_WRITE); // set PKEY_DISABLE_WRITE again
 
 Now when it frees the memory, it will also free the pkey since it
-is no longer in use:
+is no longer in use::
 
 	munmap(ptr, PAGE_SIZE);
 	pkey_free(pkey);
 
-(Note: pkey_set() is a wrapper for the RDPKRU and WRPKRU instructions.
- An example implementation can be found in
- tools/testing/selftests/x86/protection_keys.c)
+.. note:: pkey_set() is a wrapper for the RDPKRU and WRPKRU instructions.
+          An example implementation can be found in
+          tools/testing/selftests/x86/protection_keys.c.
 
-=========================== Behavior ===========================
+Behavior
+========
 
 The kernel attempts to make protection keys consistent with the
-behavior of a plain mprotect().  For instance if you do this:
+behavior of a plain mprotect().  For instance if you do this::
 
 	mprotect(ptr, size, PROT_NONE);
 	something(ptr);
 
-you can expect the same effects with protection keys when doing this:
+you can expect the same effects with protection keys when doing this::
 
 	pkey = pkey_alloc(0, PKEY_DISABLE_WRITE | PKEY_DISABLE_READ);
 	pkey_mprotect(ptr, size, PROT_READ|PROT_WRITE, pkey);
 	something(ptr);
 
 That should be true whether something() is a direct access to 'ptr'
-like:
+like::
 
 	*ptr = foo;
 
 or when the kernel does the access on the application's behalf like
-with a read():
+with a read()::
 
 	read(fd, ptr, 1);
 
-- 
2.20.1


  parent reply	other threads:[~2019-05-08 15:23 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-08 15:21 [PATCH v4 00/27] Include linux x86 docs into Sphinx TOC tree Changbin Du
2019-05-08 15:21 ` [PATCH v4 01/27] Documentation: add Linux x86 docs to " Changbin Du
2019-05-08 15:21 ` [PATCH v4 02/27] Documentation: x86: convert boot.txt to reST Changbin Du
2019-05-08 15:21 ` [PATCH v4 03/27] Documentation: x86: convert topology.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 04/27] Documentation: x86: convert exception-tables.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 05/27] Documentation: x86: convert kernel-stacks " Changbin Du
2019-05-08 15:21 ` [PATCH v4 06/27] Documentation: x86: convert entry_64.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 07/27] Documentation: x86: convert earlyprintk.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 08/27] Documentation: x86: convert zero-page.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 09/27] Documentation: x86: convert tlb.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 10/27] Documentation: x86: convert mtrr.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 11/27] Documentation: x86: convert pat.txt " Changbin Du
2019-05-08 15:21 ` Changbin Du [this message]
2019-05-08 15:21 ` [PATCH v4 13/27] Documentation: x86: convert intel_mpx.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 14/27] Documentation: x86: convert amd-memory-encryption.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 15/27] Documentation: x86: convert pti.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 16/27] Documentation: x86: convert microcode.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 17/27] Documentation: x86: convert resctrl_ui.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 18/27] Documentation: x86: convert orc-unwinder.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 19/27] Documentation: x86: convert usb-legacy-support.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 20/27] Documentation: x86: convert i386/IO-APIC.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 21/27] Documentation: x86: convert x86_64/boot-options.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 22/27] Documentation: x86: convert x86_64/uefi.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 23/27] Documentation: x86: convert x86_64/mm.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 24/27] Documentation: x86: convert x86_64/5level-paging.txt " Changbin Du
2019-05-08 15:21 ` [PATCH v4 25/27] Documentation: x86: convert x86_64/fake-numa-for-cpusets " Changbin Du
2019-05-08 15:21 ` [PATCH v4 26/27] Documentation: x86: convert x86_64/cpu-hotplug-spec " Changbin Du
2019-05-08 15:21 ` [PATCH v4 27/27] Documentation: x86: convert x86_64/machinecheck " Changbin Du
2019-05-08 20:40 ` [PATCH v4 00/27] Include linux x86 docs into Sphinx TOC tree Jonathan Corbet

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