path: root/Documentation
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authorJames Bottomley <JBottomley@Parallels.com>2012-05-21 12:17:30 +0100
committerJames Bottomley <JBottomley@Parallels.com>2012-05-21 12:17:30 +0100
commite34693336564f02b3e2cc09d8b872aef22a154e9 (patch)
tree09f51f10f9406042f9176e39b4dc8de850ba712e /Documentation
parent76b311fdbdd2e16e5d39cd496a67aa1a1b948914 (diff)
parentde2eb4d5c5c25e8fb75d1e19092f24b83cb7d8d5 (diff)
Merge tag 'isci-for-3.5' into misc
isci update for 3.5 1/ Rework remote-node-context (RNC) handling for proper management of the silicon state machine in error handling and hot-plug conditions. Further details below, suffice to say if the RNC is mismanaged the silicon state machines may lock up. 2/ Refactor the initialization code to be reused for suspend/resume support 3/ Miscellaneous bug fixes to address discovery issues and hardware compatibility. RNC rework details from Jeff Skirvin: In the controller, devices as they appear on a SAS domain (or direct-attached SATA devices) are represented by memory structures known as "Remote Node Contexts" (RNCs). These structures are transferred from main memory to the controller using a set of register commands; these commands include setting up the context ("posting"), removing the context ("invalidating"), and commands to control the scheduling of commands and connections to that remote device ("suspensions" and "resumptions"). There is a similar path to control RNC scheduling from the protocol engine, which interprets the results of command and data transmission and reception. In general, the controller chooses among non-suspended RNCs to find one that has work requiring scheduling the transmission of command and data frames to a target. Likewise, when a target tries to return data back to the initiator, the state of the RNC is used by the controller to determine how to treat the incoming request. As an example, if the RNC is in the state "TX/RX Suspended", incoming SSP connection requests from the target will be rejected by the controller hardware. When an RNC is "TX Suspended", it will not be selected by the controller hardware to start outgoing command or data operations (with certain priority-based exceptions). As mentioned above, there are two sources for management of the RNC states: commands from driver software, and the result of transmission and reception conditions of commands and data signaled by the controller hardware. As an example of the latter, if an outgoing SSP command ends with a OPEN_REJECT(BAD_DESTINATION) status, the RNC state will transition to the "TX Suspended" state, and this is signaled by the controller hardware in the status to the completion of the pending command as well as signaled in a controller hardware event. Examples of the former are included in the patch changelogs. Driver software is required to suspend the RNC in a "TX/RX Suspended" condition before any outstanding commands can be terminated. Failure to guarantee this can lead to a complete hardware hang condition. Earlier versions of the driver software did not guarantee that an RNC was correctly managed before I/O termination, and so operated in an unsafe way. Further, the driver performed unnecessary contortions to preserve the remote device command state and so was more complicated than it needed to be. A simplifying driver assumption is that once an I/O has entered the error handler path without having completed in the target, the requirement on the driver is that all use of the sas_task must end. Beyond that, recovery of operation is dependent on libsas and other components to reset, rediscover and reconfigure the device before normal operation can restart. In the driver, this simplifying assumption meant that the RNC management could be reduced to entry into the suspended state, terminating the targeted I/O request, and resuming the RNC as needed for device-specific management such as an SSP Abort Task or LUN Reset Management request.
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/ata/ahci-platform.txt (renamed from Documentation/devicetree/bindings/ata/calxeda-sata.txt)5
8 files changed, 59 insertions, 26 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-hsi b/Documentation/ABI/testing/sysfs-bus-hsi
new file mode 100644
index 00000000000..1b1b282a99e
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-hsi
@@ -0,0 +1,19 @@
+What: /sys/bus/hsi
+Date: April 2012
+KernelVersion: 3.4
+Contact: Carlos Chinea <carlos.chinea@nokia.com>
+ High Speed Synchronous Serial Interface (HSI) is a
+ serial interface mainly used for connecting application
+ engines (APE) with cellular modem engines (CMT) in cellular
+ handsets.
+ The bus will be populated with devices (hsi_clients) representing
+ the protocols available in the system. Bus drivers implement
+ those protocols.
+What: /sys/bus/hsi/devices/.../modalias
+Date: April 2012
+KernelVersion: 3.4
+Contact: Carlos Chinea <carlos.chinea@nokia.com>
+Description: Stores the same MODALIAS value emitted by uevent
+ Format: hsi:<hsi_client device name>
diff --git a/Documentation/DocBook/media/v4l/pixfmt-nv12m.xml b/Documentation/DocBook/media/v4l/pixfmt-nv12m.xml
index 3fd3ce5df27..5274c24d11e 100644
--- a/Documentation/DocBook/media/v4l/pixfmt-nv12m.xml
+++ b/Documentation/DocBook/media/v4l/pixfmt-nv12m.xml
@@ -1,6 +1,6 @@
<refentry id="V4L2-PIX-FMT-NV12M">
- <refentrytitle>V4L2_PIX_FMT_NV12M ('NV12M')</refentrytitle>
+ <refentrytitle>V4L2_PIX_FMT_NV12M ('NM12')</refentrytitle>
diff --git a/Documentation/DocBook/media/v4l/pixfmt-yuv420m.xml b/Documentation/DocBook/media/v4l/pixfmt-yuv420m.xml
index 9957863daf1..60308f1eefd 100644
--- a/Documentation/DocBook/media/v4l/pixfmt-yuv420m.xml
+++ b/Documentation/DocBook/media/v4l/pixfmt-yuv420m.xml
@@ -1,6 +1,6 @@
<refentry id="V4L2-PIX-FMT-YUV420M">
- <refentrytitle>V4L2_PIX_FMT_YUV420M ('YU12M')</refentrytitle>
+ <refentrytitle>V4L2_PIX_FMT_YUV420M ('YM12')</refentrytitle>
diff --git a/Documentation/devicetree/bindings/ata/calxeda-sata.txt b/Documentation/devicetree/bindings/ata/ahci-platform.txt
index 79caa5651f5..8bb8a76d42e 100644
--- a/Documentation/devicetree/bindings/ata/calxeda-sata.txt
+++ b/Documentation/devicetree/bindings/ata/ahci-platform.txt
@@ -1,10 +1,10 @@
-* Calxeda SATA Controller
+* AHCI SATA Controller
SATA nodes are defined to describe on-chip Serial ATA controllers.
Each SATA controller should have its own node.
Required properties:
-- compatible : compatible list, contains "calxeda,hb-ahci"
+- compatible : compatible list, contains "calxeda,hb-ahci" or "snps,spear-ahci"
- interrupts : <interrupt mapping for SATA IRQ>
- reg : <registers mapping>
@@ -14,4 +14,3 @@ Example:
reg = <0xffe08000 0x1000>;
interrupts = <115>;
diff --git a/Documentation/devicetree/bindings/sound/sgtl5000.txt b/Documentation/devicetree/bindings/sound/sgtl5000.txt
index 2c3cd413f04..9cc44449508 100644
--- a/Documentation/devicetree/bindings/sound/sgtl5000.txt
+++ b/Documentation/devicetree/bindings/sound/sgtl5000.txt
@@ -3,6 +3,8 @@
Required properties:
- compatible : "fsl,sgtl5000".
+- reg : the I2C address of the device
codec: sgtl5000@0a {
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index bd80ba5847d..1619a8c8087 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -147,7 +147,7 @@ tcp_adv_win_scale - INTEGER
(if tcp_adv_win_scale > 0) or bytes-bytes/2^(-tcp_adv_win_scale),
if it is <= 0.
Possible values are [-31, 31], inclusive.
- Default: 2
+ Default: 1
tcp_allowed_congestion_control - STRING
Show/set the congestion control choices available to non-privileged
@@ -410,7 +410,7 @@ tcp_rmem - vector of 3 INTEGERs: min, default, max
net.core.rmem_max. Calling setsockopt() with SO_RCVBUF disables
automatic tuning of that socket's receive buffer size, in which
case this value is ignored.
- Default: between 87380B and 4MB, depending on RAM size.
+ Default: between 87380B and 6MB, depending on RAM size.
tcp_sack - BOOLEAN
Enable select acknowledgments (SACKS).
diff --git a/Documentation/power/freezing-of-tasks.txt b/Documentation/power/freezing-of-tasks.txt
index ec715cd78fb..6ec291ea1c7 100644
--- a/Documentation/power/freezing-of-tasks.txt
+++ b/Documentation/power/freezing-of-tasks.txt
@@ -9,7 +9,7 @@ architectures).
II. How does it work?
-There are four per-task flags used for that, PF_NOFREEZE, PF_FROZEN, TIF_FREEZE
+There are three per-task flags used for that, PF_NOFREEZE, PF_FROZEN
and PF_FREEZER_SKIP (the last one is auxiliary). The tasks that have
PF_NOFREEZE unset (all user space processes and some kernel threads) are
regarded as 'freezable' and treated in a special way before the system enters a
@@ -17,30 +17,31 @@ suspend state as well as before a hibernation image is created (in what follows
we only consider hibernation, but the description also applies to suspend).
Namely, as the first step of the hibernation procedure the function
-freeze_processes() (defined in kernel/power/process.c) is called. It executes
-try_to_freeze_tasks() that sets TIF_FREEZE for all of the freezable tasks and
-either wakes them up, if they are kernel threads, or sends fake signals to them,
-if they are user space processes. A task that has TIF_FREEZE set, should react
-to it by calling the function called __refrigerator() (defined in
-kernel/freezer.c), which sets the task's PF_FROZEN flag, changes its state
-to TASK_UNINTERRUPTIBLE and makes it loop until PF_FROZEN is cleared for it.
-Then, we say that the task is 'frozen' and therefore the set of functions
-handling this mechanism is referred to as 'the freezer' (these functions are
-defined in kernel/power/process.c, kernel/freezer.c & include/linux/freezer.h).
-User space processes are generally frozen before kernel threads.
+freeze_processes() (defined in kernel/power/process.c) is called. A system-wide
+variable system_freezing_cnt (as opposed to a per-task flag) is used to indicate
+whether the system is to undergo a freezing operation. And freeze_processes()
+sets this variable. After this, it executes try_to_freeze_tasks() that sends a
+fake signal to all user space processes, and wakes up all the kernel threads.
+All freezable tasks must react to that by calling try_to_freeze(), which
+results in a call to __refrigerator() (defined in kernel/freezer.c), which sets
+the task's PF_FROZEN flag, changes its state to TASK_UNINTERRUPTIBLE and makes
+it loop until PF_FROZEN is cleared for it. Then, we say that the task is
+'frozen' and therefore the set of functions handling this mechanism is referred
+to as 'the freezer' (these functions are defined in kernel/power/process.c,
+kernel/freezer.c & include/linux/freezer.h). User space processes are generally
+frozen before kernel threads.
__refrigerator() must not be called directly. Instead, use the
try_to_freeze() function (defined in include/linux/freezer.h), that checks
-the task's TIF_FREEZE flag and makes the task enter __refrigerator() if the
-flag is set.
+if the task is to be frozen and makes the task enter __refrigerator().
For user space processes try_to_freeze() is called automatically from the
signal-handling code, but the freezable kernel threads need to call it
explicitly in suitable places or use the wait_event_freezable() or
wait_event_freezable_timeout() macros (defined in include/linux/freezer.h)
-that combine interruptible sleep with checking if TIF_FREEZE is set and calling
-try_to_freeze(). The main loop of a freezable kernel thread may look like the
-following one:
+that combine interruptible sleep with checking if the task is to be frozen and
+calling try_to_freeze(). The main loop of a freezable kernel thread may look
+like the following one:
do {
@@ -53,7 +54,7 @@ following one:
(from drivers/usb/core/hub.c::hub_thread()).
If a freezable kernel thread fails to call try_to_freeze() after the freezer has
-set TIF_FREEZE for it, the freezing of tasks will fail and the entire
+initiated a freezing operation, the freezing of tasks will fail and the entire
hibernation operation will be cancelled. For this reason, freezable kernel
threads must call try_to_freeze() somewhere or use one of the
wait_event_freezable() and wait_event_freezable_timeout() macros.
diff --git a/Documentation/security/keys.txt b/Documentation/security/keys.txt
index 78771709142..d389acd31e1 100644
--- a/Documentation/security/keys.txt
+++ b/Documentation/security/keys.txt
@@ -123,7 +123,7 @@ KEY SERVICE OVERVIEW
The key service provides a number of features besides keys:
- (*) The key service defines two special key types:
+ (*) The key service defines three special key types:
(+) "keyring"
@@ -137,6 +137,18 @@ The key service provides a number of features besides keys:
blobs of data. These can be created, updated and read by userspace,
and aren't intended for use by kernel services.
+ (+) "logon"
+ Like a "user" key, a "logon" key has a payload that is an arbitrary
+ blob of data. It is intended as a place to store secrets which are
+ accessible to the kernel but not to userspace programs.
+ The description can be arbitrary, but must be prefixed with a non-zero
+ length string that describes the key "subclass". The subclass is
+ separated from the rest of the description by a ':'. "logon" keys can
+ be created and updated from userspace, but the payload is only
+ readable from kernel space.
(*) Each process subscribes to three keyrings: a thread-specific keyring, a
process-specific keyring, and a session-specific keyring.