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authorDavid S. Miller <davem@davemloft.net>2018-11-28 22:10:54 -0800
committerDavid S. Miller <davem@davemloft.net>2018-11-28 22:10:54 -0800
commite561bb29b650d2817d10a4858f1817836ed08399 (patch)
tree0bc92b5bb8a287a8e4a88732f3c64b56d126da58 /Documentation
parentnet: qualcomm: rmnet: remove set but not used variables 'ip_family, fc_seq, qos_id' (diff)
parentMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net (diff)
downloadlinux-dev-e561bb29b650d2817d10a4858f1817836ed08399.tar.xz
linux-dev-e561bb29b650d2817d10a4858f1817836ed08399.zip
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Trivial conflict in net/core/filter.c, a locally computed 'sdif' is now an argument to the function. Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/core-api/xarray.rst52
-rw-r--r--Documentation/devicetree/bindings/spi/spi-uniphier.txt14
-rw-r--r--Documentation/input/event-codes.rst11
3 files changed, 50 insertions, 27 deletions
diff --git a/Documentation/core-api/xarray.rst b/Documentation/core-api/xarray.rst
index a4e705108f42..dbe96cb5558e 100644
--- a/Documentation/core-api/xarray.rst
+++ b/Documentation/core-api/xarray.rst
@@ -74,7 +74,8 @@ using :c:func:`xa_load`. xa_store will overwrite any entry with the
new entry and return the previous entry stored at that index. You can
use :c:func:`xa_erase` instead of calling :c:func:`xa_store` with a
``NULL`` entry. There is no difference between an entry that has never
-been stored to and one that has most recently had ``NULL`` stored to it.
+been stored to, one that has been erased and one that has most recently
+had ``NULL`` stored to it.
You can conditionally replace an entry at an index by using
:c:func:`xa_cmpxchg`. Like :c:func:`cmpxchg`, it will only succeed if
@@ -105,23 +106,44 @@ may result in the entry being marked at some, but not all of the other
indices. Storing into one index may result in the entry retrieved by
some, but not all of the other indices changing.
+Sometimes you need to ensure that a subsequent call to :c:func:`xa_store`
+will not need to allocate memory. The :c:func:`xa_reserve` function
+will store a reserved entry at the indicated index. Users of the normal
+API will see this entry as containing ``NULL``. If you do not need to
+use the reserved entry, you can call :c:func:`xa_release` to remove the
+unused entry. If another user has stored to the entry in the meantime,
+:c:func:`xa_release` will do nothing; if instead you want the entry to
+become ``NULL``, you should use :c:func:`xa_erase`.
+
+If all entries in the array are ``NULL``, the :c:func:`xa_empty` function
+will return ``true``.
+
Finally, you can remove all entries from an XArray by calling
:c:func:`xa_destroy`. If the XArray entries are pointers, you may wish
to free the entries first. You can do this by iterating over all present
entries in the XArray using the :c:func:`xa_for_each` iterator.
-ID assignment
--------------
+Allocating XArrays
+------------------
+
+If you use :c:func:`DEFINE_XARRAY_ALLOC` to define the XArray, or
+initialise it by passing ``XA_FLAGS_ALLOC`` to :c:func:`xa_init_flags`,
+the XArray changes to track whether entries are in use or not.
You can call :c:func:`xa_alloc` to store the entry at any unused index
in the XArray. If you need to modify the array from interrupt context,
you can use :c:func:`xa_alloc_bh` or :c:func:`xa_alloc_irq` to disable
-interrupts while allocating the ID. Unlike :c:func:`xa_store`, allocating
-a ``NULL`` pointer does not delete an entry. Instead it reserves an
-entry like :c:func:`xa_reserve` and you can release it using either
-:c:func:`xa_erase` or :c:func:`xa_release`. To use ID assignment, the
-XArray must be defined with :c:func:`DEFINE_XARRAY_ALLOC`, or initialised
-by passing ``XA_FLAGS_ALLOC`` to :c:func:`xa_init_flags`,
+interrupts while allocating the ID.
+
+Using :c:func:`xa_store`, :c:func:`xa_cmpxchg` or :c:func:`xa_insert`
+will mark the entry as being allocated. Unlike a normal XArray, storing
+``NULL`` will mark the entry as being in use, like :c:func:`xa_reserve`.
+To free an entry, use :c:func:`xa_erase` (or :c:func:`xa_release` if
+you only want to free the entry if it's ``NULL``).
+
+You cannot use ``XA_MARK_0`` with an allocating XArray as this mark
+is used to track whether an entry is free or not. The other marks are
+available for your use.
Memory allocation
-----------------
@@ -158,6 +180,8 @@ Takes RCU read lock:
Takes xa_lock internally:
* :c:func:`xa_store`
+ * :c:func:`xa_store_bh`
+ * :c:func:`xa_store_irq`
* :c:func:`xa_insert`
* :c:func:`xa_erase`
* :c:func:`xa_erase_bh`
@@ -167,6 +191,9 @@ Takes xa_lock internally:
* :c:func:`xa_alloc`
* :c:func:`xa_alloc_bh`
* :c:func:`xa_alloc_irq`
+ * :c:func:`xa_reserve`
+ * :c:func:`xa_reserve_bh`
+ * :c:func:`xa_reserve_irq`
* :c:func:`xa_destroy`
* :c:func:`xa_set_mark`
* :c:func:`xa_clear_mark`
@@ -177,6 +204,7 @@ Assumes xa_lock held on entry:
* :c:func:`__xa_erase`
* :c:func:`__xa_cmpxchg`
* :c:func:`__xa_alloc`
+ * :c:func:`__xa_reserve`
* :c:func:`__xa_set_mark`
* :c:func:`__xa_clear_mark`
@@ -234,7 +262,8 @@ Sharing the XArray with interrupt context is also possible, either
using :c:func:`xa_lock_irqsave` in both the interrupt handler and process
context, or :c:func:`xa_lock_irq` in process context and :c:func:`xa_lock`
in the interrupt handler. Some of the more common patterns have helper
-functions such as :c:func:`xa_erase_bh` and :c:func:`xa_erase_irq`.
+functions such as :c:func:`xa_store_bh`, :c:func:`xa_store_irq`,
+:c:func:`xa_erase_bh` and :c:func:`xa_erase_irq`.
Sometimes you need to protect access to the XArray with a mutex because
that lock sits above another mutex in the locking hierarchy. That does
@@ -322,7 +351,8 @@ to :c:func:`xas_retry`, and retry the operation if it returns ``true``.
- :c:func:`xa_is_zero`
- Zero entries appear as ``NULL`` through the Normal API, but occupy
an entry in the XArray which can be used to reserve the index for
- future use.
+ future use. This is used by allocating XArrays for allocated entries
+ which are ``NULL``.
Other internal entries may be added in the future. As far as possible, they
will be handled by :c:func:`xas_retry`.
diff --git a/Documentation/devicetree/bindings/spi/spi-uniphier.txt b/Documentation/devicetree/bindings/spi/spi-uniphier.txt
index 504a4ecfc7b1..b04e66a52de5 100644
--- a/Documentation/devicetree/bindings/spi/spi-uniphier.txt
+++ b/Documentation/devicetree/bindings/spi/spi-uniphier.txt
@@ -5,18 +5,20 @@ UniPhier SoCs have SCSSI which supports SPI single channel.
Required properties:
- compatible: should be "socionext,uniphier-scssi"
- reg: address and length of the spi master registers
- - #address-cells: must be <1>, see spi-bus.txt
- - #size-cells: must be <0>, see spi-bus.txt
- - clocks: A phandle to the clock for the device.
- - resets: A phandle to the reset control for the device.
+ - interrupts: a single interrupt specifier
+ - pinctrl-names: should be "default"
+ - pinctrl-0: pin control state for the default mode
+ - clocks: a phandle to the clock for the device
+ - resets: a phandle to the reset control for the device
Example:
spi0: spi@54006000 {
compatible = "socionext,uniphier-scssi";
reg = <0x54006000 0x100>;
- #address-cells = <1>;
- #size-cells = <0>;
+ interrupts = <0 39 4>;
+ pinctrl-names = "default";
+ pinctrl-0 = <&pinctrl_spi0>;
clocks = <&peri_clk 11>;
resets = <&peri_rst 11>;
};
diff --git a/Documentation/input/event-codes.rst b/Documentation/input/event-codes.rst
index cef220c176a4..a8c0873beb95 100644
--- a/Documentation/input/event-codes.rst
+++ b/Documentation/input/event-codes.rst
@@ -190,16 +190,7 @@ A few EV_REL codes have special meanings:
* REL_WHEEL, REL_HWHEEL:
- These codes are used for vertical and horizontal scroll wheels,
- respectively. The value is the number of "notches" moved on the wheel, the
- physical size of which varies by device. For high-resolution wheels (which
- report multiple events for each notch of movement, or do not have notches)
- this may be an approximation based on the high-resolution scroll events.
-
-* REL_WHEEL_HI_RES:
-
- - If a vertical scroll wheel supports high-resolution scrolling, this code
- will be emitted in addition to REL_WHEEL. The value is the (approximate)
- distance travelled by the user's finger, in microns.
+ respectively.
EV_ABS
------