core: Support memfd transport; bump protocol version

Now that all layers in the stack support memfd blocks, add memfd
support for the daemon's global core mempool. Also introduce
"enable-memfd=" daemon argument and configuration option.

For now, memfd support is an opt-in feature to be activated only
when daemon's enable-memfd= is set to yes.

Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>

2 files changed, 18 insertions, 4 deletions

diff --git a/man/pulse-daemon.conf.5.xml.in b/man/pulse-daemon.conf.5.xml.in
index 0367b1ff3..1abc94fc2 100644
--- a/man/pulse-daemon.conf.5.xml.in
+++ b/man/pulse-daemon.conf.5.xml.in
@@ -189,12 +189,17 @@ License along with PulseAudio; if not, see <http://www.gnu.org/licenses/>.
 
     <option>
       <p><opt>enable-shm=</opt> Enable data transfer via POSIX
-      shared memory. Takes a boolean argument, defaults to
+      or memfd shared memory. Takes a boolean argument, defaults to
       <opt>yes</opt>. The <opt>--disable-shm</opt> command line
       argument takes precedence.</p>
     </option>
 
     <option>
+      <p><opt>enable-memfd=</opt>. Enable memfd shared memory. Takes
+      a boolean argument, defaults to <opt>no</opt>.</p>
+    </option>
+
+    <option>
       <p><opt>shm-size-bytes=</opt> Sets the shared memory segment
       size for the daemon, in bytes. If left unspecified or is set to 0
       it will default to some system-specific default, usually 64
diff --git a/man/pulseaudio.1.xml.in b/man/pulseaudio.1.xml.in
index 650b417b0..3187ef5d4 100644
--- a/man/pulseaudio.1.xml.in
+++ b/man/pulseaudio.1.xml.in
@@ -292,14 +292,23 @@ License along with PulseAudio; if not, see <http://www.gnu.org/licenses/>.
       <p><opt>--disable-shm</opt><arg>[=BOOL]</arg></p>
 
       <optdesc><p>PulseAudio clients and the server can exchange audio
-      data via POSIX shared memory segments (on systems that support
-      this). If disabled PulseAudio will communicate exclusively over
-      sockets. Please note that data transfer via shared memory
+      data via POSIX or memfd shared memory segments (on systems that
+      support this). If disabled PulseAudio will communicate exclusively
+      over sockets. Please note that data transfer via shared memory
       segments is always disabled when PulseAudio is running with
       <opt>--system</opt> enabled (see above).</p></optdesc>
     </option>
 
     <option>
+      <p><opt>--enable-memfd</opt><arg>[=BOOL]</arg></p>
+
+      <optdesc><p>PulseAudio clients and the server can exchange audio
+      data via memfds - the anonymous Linux Kernel shared memory mechanism
+      (on kernels that support this). If disabled PulseAudio will
+      communicate via POSIX shared memory.</p></optdesc>
+    </option>
+
+    <option>
       <p><opt>-L | --load</opt><arg>="MODULE ARGUMENTS"</arg></p>
 
       <optdesc><p>Load the specified plugin module with the specified