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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /lib/parman.c | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni:
"A new driver this cycle, for the AMD AXI I3C controller.
There are also new features such as IBI wakeup support, SETAASA device
discovery and ACPI support for the the DAA methods, meaning we can now
communicate with the SPD devices on DDR5 modules.
New driver:
- AMD AXI I3C master controller
Subsystem:
- I3C Common Command Code (CCC) handling improvements, especially
around GET CCCs
- SETAASA device discovery support
- ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
well as I2C devices on I3C bus
- IBI-based wakeup support
Drivers:
- dw: SETAASA support
- mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
controller support, PIO queue management support for HCI v1.2
- renesas: improve suspend to RAM support, add runtime PM support"
* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
i3c: dw: reduce do_daa time if there's no client
i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
i3c: dw: rename "pclk" to "apb" to match dt-binding
i3c: dw: make struct dw_i3c_cmd smaller
i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
i3c: renesas: Don't register devices when ENTDAA times out
i3c: master: dw-i3c-master: fix OD timing for first broadcast
i3c: mipi-i3c-hci: Advertise IBI wakeup capability
i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
i3c: master: Reject IBI requests from non-IBI-capable devices
i3c: master: Add helper to query bus wakeup requirements
i3c: master: Report wakeup events for IBIs
i3c: master: Support IBI-based wakeup capability
i3c: master: Fix potential UAF in i3c_device_match()
i3c: master: Fix potential UAF in i3c_device_uevent()
i3c: Make dev->desc locking assumptions explicit
i3c: master: Fix use-after-free of master->this
...
Diffstat (limited to 'lib/parman.c')
| -rw-r--r-- | lib/parman.c | 375 |
1 files changed, 375 insertions, 0 deletions
diff --git a/lib/parman.c b/lib/parman.c new file mode 100644 index 000000000..0de691c20 --- /dev/null +++ b/lib/parman.c @@ -0,0 +1,375 @@ +/* + * lib/parman.c - Manager for linear priority array areas + * Copyright (c) 2017 Mellanox Technologies. All rights reserved. + * Copyright (c) 2017 Jiri Pirko <jiri@mellanox.com> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the names of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * Alternatively, this software may be distributed under the terms of the + * GNU General Public License ("GPL") version 2 as published by the Free + * Software Foundation. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/export.h> +#include <linux/list.h> +#include <linux/err.h> +#include <linux/parman.h> + +struct parman_algo { + int (*item_add)(struct parman *parman, struct parman_prio *prio, + struct parman_item *item); + void (*item_remove)(struct parman *parman, struct parman_prio *prio, + struct parman_item *item); +}; + +struct parman { + const struct parman_ops *ops; + void *priv; + const struct parman_algo *algo; + unsigned long count; + unsigned long limit_count; + struct list_head prio_list; +}; + +static int parman_enlarge(struct parman *parman) +{ + unsigned long new_count = parman->limit_count + + parman->ops->resize_step; + int err; + + err = parman->ops->resize(parman->priv, new_count); + if (err) + return err; + parman->limit_count = new_count; + return 0; +} + +static int parman_shrink(struct parman *parman) +{ + unsigned long new_count = parman->limit_count - + parman->ops->resize_step; + int err; + + if (new_count < parman->ops->base_count) + return 0; + err = parman->ops->resize(parman->priv, new_count); + if (err) + return err; + parman->limit_count = new_count; + return 0; +} + +static bool parman_prio_used(struct parman_prio *prio) +{ + return !list_empty(&prio->item_list); +} + +static struct parman_item *parman_prio_first_item(struct parman_prio *prio) +{ + return list_first_entry(&prio->item_list, + typeof(struct parman_item), list); +} + +static unsigned long parman_prio_first_index(struct parman_prio *prio) +{ + return parman_prio_first_item(prio)->index; +} + +static struct parman_item *parman_prio_last_item(struct parman_prio *prio) +{ + return list_last_entry(&prio->item_list, + typeof(struct parman_item), list); +} + +static unsigned long parman_prio_last_index(struct parman_prio *prio) +{ + return parman_prio_last_item(prio)->index; +} + +static unsigned long parman_lsort_new_index_find(struct parman *parman, + struct parman_prio *prio) +{ + list_for_each_entry_from_reverse(prio, &parman->prio_list, list) { + if (!parman_prio_used(prio)) + continue; + return parman_prio_last_index(prio) + 1; + } + return 0; +} + +static void __parman_prio_move(struct parman *parman, struct parman_prio *prio, + struct parman_item *item, unsigned long to_index, + unsigned long count) +{ + parman->ops->move(parman->priv, item->index, to_index, count); +} + +static void parman_prio_shift_down(struct parman *parman, + struct parman_prio *prio) +{ + struct parman_item *item; + unsigned long to_index; + + if (!parman_prio_used(prio)) + return; + item = parman_prio_first_item(prio); + to_index = parman_prio_last_index(prio) + 1; + __parman_prio_move(parman, prio, item, to_index, 1); + list_move_tail(&item->list, &prio->item_list); + item->index = to_index; +} + +static void parman_prio_shift_up(struct parman *parman, + struct parman_prio *prio) +{ + struct parman_item *item; + unsigned long to_index; + + if (!parman_prio_used(prio)) + return; + item = parman_prio_last_item(prio); + to_index = parman_prio_first_index(prio) - 1; + __parman_prio_move(parman, prio, item, to_index, 1); + list_move(&item->list, &prio->item_list); + item->index = to_index; +} + +static void parman_prio_item_remove(struct parman *parman, + struct parman_prio *prio, + struct parman_item *item) +{ + struct parman_item *last_item; + unsigned long to_index; + + last_item = parman_prio_last_item(prio); + if (last_item == item) { + list_del(&item->list); + return; + } + to_index = item->index; + __parman_prio_move(parman, prio, last_item, to_index, 1); + list_del(&last_item->list); + list_replace(&item->list, &last_item->list); + last_item->index = to_index; +} + +static int parman_lsort_item_add(struct parman *parman, + struct parman_prio *prio, + struct parman_item *item) +{ + struct parman_prio *prio2; + unsigned long new_index; + int err; + + if (parman->count + 1 > parman->limit_count) { + err = parman_enlarge(parman); + if (err) + return err; + } + + new_index = parman_lsort_new_index_find(parman, prio); + list_for_each_entry_reverse(prio2, &parman->prio_list, list) { + if (prio2 == prio) + break; + parman_prio_shift_down(parman, prio2); + } + item->index = new_index; + list_add_tail(&item->list, &prio->item_list); + parman->count++; + return 0; +} + +static void parman_lsort_item_remove(struct parman *parman, + struct parman_prio *prio, + struct parman_item *item) +{ + parman_prio_item_remove(parman, prio, item); + list_for_each_entry_continue(prio, &parman->prio_list, list) + parman_prio_shift_up(parman, prio); + parman->count--; + if (parman->limit_count - parman->count >= parman->ops->resize_step) + parman_shrink(parman); +} + +static const struct parman_algo parman_lsort = { + .item_add = parman_lsort_item_add, + .item_remove = parman_lsort_item_remove, +}; + +static const struct parman_algo *parman_algos[] = { + &parman_lsort, +}; + +/** + * parman_create - creates a new parman instance + * @ops: caller-specific callbacks + * @priv: pointer to a private data passed to the ops + * + * Note: all locking must be provided by the caller. + * + * Each parman instance manages an array area with chunks of entries + * with the same priority. Consider following example: + * + * item 1 with prio 10 + * item 2 with prio 10 + * item 3 with prio 10 + * item 4 with prio 20 + * item 5 with prio 20 + * item 6 with prio 30 + * item 7 with prio 30 + * item 8 with prio 30 + * + * In this example, there are 3 priority chunks. The order of the priorities + * matters, however the order of items within a single priority chunk does not + * matter. So the same array could be ordered as follows: + * + * item 2 with prio 10 + * item 3 with prio 10 + * item 1 with prio 10 + * item 5 with prio 20 + * item 4 with prio 20 + * item 7 with prio 30 + * item 8 with prio 30 + * item 6 with prio 30 + * + * The goal of parman is to maintain the priority ordering. The caller + * provides @ops with callbacks parman uses to move the items + * and resize the array area. + * + * Returns a pointer to newly created parman instance in case of success, + * otherwise it returns NULL. + */ +struct parman *parman_create(const struct parman_ops *ops, void *priv) +{ + struct parman *parman; + + parman = kzalloc_obj(*parman); + if (!parman) + return NULL; + INIT_LIST_HEAD(&parman->prio_list); + parman->ops = ops; + parman->priv = priv; + parman->limit_count = ops->base_count; + parman->algo = parman_algos[ops->algo]; + return parman; +} +EXPORT_SYMBOL(parman_create); + +/** + * parman_destroy - destroys existing parman instance + * @parman: parman instance + * + * Note: all locking must be provided by the caller. + */ +void parman_destroy(struct parman *parman) +{ + WARN_ON(!list_empty(&parman->prio_list)); + kfree(parman); +} +EXPORT_SYMBOL(parman_destroy); + +/** + * parman_prio_init - initializes a parman priority chunk + * @parman: parman instance + * @prio: parman prio structure to be initialized + * @priority: desired priority of the chunk + * + * Note: all locking must be provided by the caller. + * + * Before caller could add an item with certain priority, he has to + * initialize a priority chunk for it using this function. + */ +void parman_prio_init(struct parman *parman, struct parman_prio *prio, + unsigned long priority) +{ + struct parman_prio *prio2; + struct list_head *pos; + + INIT_LIST_HEAD(&prio->item_list); + prio->priority = priority; + + /* Position inside the list according to priority */ + list_for_each(pos, &parman->prio_list) { + prio2 = list_entry(pos, typeof(*prio2), list); + if (prio2->priority > prio->priority) + break; + } + list_add_tail(&prio->list, pos); +} +EXPORT_SYMBOL(parman_prio_init); + +/** + * parman_prio_fini - finalizes use of parman priority chunk + * @prio: parman prio structure + * + * Note: all locking must be provided by the caller. + */ +void parman_prio_fini(struct parman_prio *prio) +{ + WARN_ON(parman_prio_used(prio)); + list_del(&prio->list); +} +EXPORT_SYMBOL(parman_prio_fini); + +/** + * parman_item_add - adds a parman item under defined priority + * @parman: parman instance + * @prio: parman prio instance to add the item to + * @item: parman item instance + * + * Note: all locking must be provided by the caller. + * + * Adds item to a array managed by parman instance under the specified priority. + * + * Returns 0 in case of success, negative number to indicate an error. + */ +int parman_item_add(struct parman *parman, struct parman_prio *prio, + struct parman_item *item) +{ + return parman->algo->item_add(parman, prio, item); +} +EXPORT_SYMBOL(parman_item_add); + +/** + * parman_item_remove - deletes parman item + * @parman: parman instance + * @prio: parman prio instance to delete the item from + * @item: parman item instance + * + * Note: all locking must be provided by the caller. + */ +void parman_item_remove(struct parman *parman, struct parman_prio *prio, + struct parman_item *item) +{ + parman->algo->item_remove(parman, prio, item); +} +EXPORT_SYMBOL(parman_item_remove); + +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_AUTHOR("Jiri Pirko <jiri@mellanox.com>"); +MODULE_DESCRIPTION("Priority-based array manager"); |
