From cf9610f9116d55c5a66ef9f1faecacabd93a9322 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Mon, 24 Aug 2026 08:46:03 -0700 Subject: Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ... --- Documentation/bpf/maps.rst | 82 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 82 insertions(+) create mode 100644 Documentation/bpf/maps.rst (limited to 'Documentation/bpf/maps.rst') diff --git a/Documentation/bpf/maps.rst b/Documentation/bpf/maps.rst new file mode 100644 index 000000000..6f069f3d6 --- /dev/null +++ b/Documentation/bpf/maps.rst @@ -0,0 +1,82 @@ + +======== +BPF maps +======== + +BPF 'maps' provide generic storage of different types for sharing data between +kernel and user space. There are several storage types available, including +hash, array, bloom filter and radix-tree. Several of the map types exist to +support specific BPF helpers that perform actions based on the map contents. The +maps are accessed from BPF programs via BPF helpers which are documented in the +`man-pages`_ for `bpf-helpers(7)`_. + +BPF maps are accessed from user space via the ``bpf`` syscall, which provides +commands to create maps, lookup elements, update elements and delete elements. +More details of the BPF syscall are available in `ebpf-syscall`_ and in the +`man-pages`_ for `bpf(2)`_. + +Map Types +========= + +.. toctree:: + :maxdepth: 1 + :glob: + + map_* + +Usage Notes +=========== + +.. c:function:: + int bpf(int command, union bpf_attr *attr, u32 size) + +Use the ``bpf()`` system call to perform the operation specified by +``command``. The operation takes parameters provided in ``attr``. The ``size`` +argument is the size of the ``union bpf_attr`` in ``attr``. + +**BPF_MAP_CREATE** + +Create a map with the desired type and attributes in ``attr``: + +.. code-block:: c + + int fd; + union bpf_attr attr = { + .map_type = BPF_MAP_TYPE_ARRAY; /* mandatory */ + .key_size = sizeof(__u32); /* mandatory */ + .value_size = sizeof(__u32); /* mandatory */ + .max_entries = 256; /* mandatory */ + .map_flags = BPF_F_MMAPABLE; + .map_name = "example_array"; + }; + + fd = bpf(BPF_MAP_CREATE, &attr, sizeof(attr)); + +Returns a process-local file descriptor on success, or negative error in case of +failure. The map can be deleted by calling ``close(fd)``. Maps held by open +file descriptors will be deleted automatically when a process exits. + +.. note:: Valid characters for ``map_name`` are ``A-Z``, ``a-z``, ``0-9``, + ``'_'`` and ``'.'``. + +**BPF_MAP_LOOKUP_ELEM** + +Lookup key in a given map using ``attr->map_fd``, ``attr->key``, +``attr->value``. Returns zero and stores found elem into ``attr->value`` on +success, or negative error on failure. + +**BPF_MAP_UPDATE_ELEM** + +Create or update key/value pair in a given map using ``attr->map_fd``, ``attr->key``, +``attr->value``. Returns zero on success or negative error on failure. + +**BPF_MAP_DELETE_ELEM** + +Find and delete element by key in a given map using ``attr->map_fd``, +``attr->key``. Returns zero on success or negative error on failure. + +.. Links: +.. _man-pages: https://www.kernel.org/doc/man-pages/ +.. _bpf(2): https://man7.org/linux/man-pages/man2/bpf.2.html +.. _bpf-helpers(7): https://man7.org/linux/man-pages/man7/bpf-helpers.7.html +.. _ebpf-syscall: https://docs.kernel.org/userspace-api/ebpf/syscall.html -- cgit v1.3.1