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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-24 08:46:03 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-24 08:46:03 -0700 |
| commit | cf9610f9116d55c5a66ef9f1faecacabd93a9322 (patch) | |
| tree | 757a3d280760c654767631cab5ad8af2d86d1848 /drivers/md/dm-vdo/wait-queue.h | |
| download | linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.tar.gz linux-stable-cf9610f9116d55c5a66ef9f1faecacabd93a9322.zip | |
Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
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
...
Diffstat (limited to 'drivers/md/dm-vdo/wait-queue.h')
| -rw-r--r-- | drivers/md/dm-vdo/wait-queue.h | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/drivers/md/dm-vdo/wait-queue.h b/drivers/md/dm-vdo/wait-queue.h new file mode 100644 index 000000000..7e8ee6afe --- /dev/null +++ b/drivers/md/dm-vdo/wait-queue.h @@ -0,0 +1,138 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright 2023 Red Hat + */ + +#ifndef VDO_WAIT_QUEUE_H +#define VDO_WAIT_QUEUE_H + +#include <linux/compiler.h> +#include <linux/types.h> + +/** + * A vdo_wait_queue is a circular singly linked list of entries waiting to be notified + * of a change in a condition. Keeping a circular list allows the vdo_wait_queue + * structure to simply be a pointer to the tail (newest) entry, supporting + * constant-time enqueue and dequeue operations. A null pointer is an empty waitq. + * + * An empty waitq: + * waitq0.last_waiter -> NULL + * + * A singleton waitq: + * waitq1.last_waiter -> entry1 -> entry1 -> [...] + * + * A three-element waitq: + * waitq2.last_waiter -> entry3 -> entry1 -> entry2 -> entry3 -> [...] + * + * linux/wait.h's wait_queue_head is _not_ used because vdo_wait_queue's + * interface is much less complex (doesn't need locking, priorities or timers). + * Made possible by vdo's thread-based resource allocation and locking; and + * the polling nature of vdo_wait_queue consumers. + * + * FIXME: could be made to use a linux/list.h's list_head but its extra barriers + * really aren't needed. Nor is a doubly linked list, but vdo_wait_queue could + * make use of __list_del_clearprev() -- but that would compromise the ability + * to make full use of linux's list interface. + */ + +struct vdo_waiter; + +struct vdo_wait_queue { + /* The tail of the queue, the last (most recently added) entry */ + struct vdo_waiter *last_waiter; + /* The number of waiters currently in the queue */ + size_t length; +}; + +/** + * vdo_waiter_callback_fn - Callback type that will be called to resume processing + * of a waiter after it has been removed from its wait queue. + */ +typedef void (*vdo_waiter_callback_fn)(struct vdo_waiter *waiter, void *context); + +/** + * vdo_waiter_match_fn - Method type for waiter matching methods. + * + * Returns false if the waiter does not match. + */ +typedef bool (*vdo_waiter_match_fn)(struct vdo_waiter *waiter, void *context); + +/* The structure for entries in a vdo_wait_queue. */ +struct vdo_waiter { + /* + * The next waiter in the waitq. If this entry is the last waiter, then this + * is actually a pointer back to the head of the waitq. + */ + struct vdo_waiter *next_waiter; + + /* Optional waiter-specific callback to invoke when dequeuing this waiter. */ + vdo_waiter_callback_fn callback; +}; + +/** + * vdo_waiter_is_waiting() - Check whether a waiter is waiting. + * @waiter: The waiter to check. + * + * Return: true if the waiter is on some vdo_wait_queue. + */ +static inline bool vdo_waiter_is_waiting(struct vdo_waiter *waiter) +{ + return (waiter->next_waiter != NULL); +} + +/** + * vdo_waitq_init() - Initialize a vdo_wait_queue. + * @waitq: The vdo_wait_queue to initialize. + */ +static inline void vdo_waitq_init(struct vdo_wait_queue *waitq) +{ + *waitq = (struct vdo_wait_queue) { + .last_waiter = NULL, + .length = 0, + }; +} + +/** + * vdo_waitq_has_waiters() - Check whether a vdo_wait_queue has any entries waiting. + * @waitq: The vdo_wait_queue to query. + * + * Return: true if there are any waiters in the waitq. + */ +static inline bool __must_check vdo_waitq_has_waiters(const struct vdo_wait_queue *waitq) +{ + return (waitq->last_waiter != NULL); +} + +void vdo_waitq_enqueue_waiter(struct vdo_wait_queue *waitq, + struct vdo_waiter *waiter); + +struct vdo_waiter *vdo_waitq_dequeue_waiter(struct vdo_wait_queue *waitq); + +void vdo_waitq_notify_all_waiters(struct vdo_wait_queue *waitq, + vdo_waiter_callback_fn callback, void *context); + +bool vdo_waitq_notify_next_waiter(struct vdo_wait_queue *waitq, + vdo_waiter_callback_fn callback, void *context); + +void vdo_waitq_transfer_all_waiters(struct vdo_wait_queue *from_waitq, + struct vdo_wait_queue *to_waitq); + +struct vdo_waiter *vdo_waitq_get_first_waiter(const struct vdo_wait_queue *waitq); + +void vdo_waitq_dequeue_matching_waiters(struct vdo_wait_queue *waitq, + vdo_waiter_match_fn waiter_match, + void *match_context, + struct vdo_wait_queue *matched_waitq); + +/** + * vdo_waitq_num_waiters() - Return the number of waiters in a vdo_wait_queue. + * @waitq: The vdo_wait_queue to query. + * + * Return: The number of waiters in the waitq. + */ +static inline size_t __must_check vdo_waitq_num_waiters(const struct vdo_wait_queue *waitq) +{ + return waitq->length; +} + +#endif /* VDO_WAIT_QUEUE_H */ |
