From 4352b8aee98005853aa63f57d6377282de17a33f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 23 Aug 2026 13:28:57 -0700 Subject: Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux 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 ... --- fs/notify/group.c | 160 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 160 insertions(+) create mode 100644 fs/notify/group.c (limited to 'fs/notify/group.c') diff --git a/fs/notify/group.c b/fs/notify/group.c new file mode 100644 index 000000000..b56d1c1d9 --- /dev/null +++ b/fs/notify/group.c @@ -0,0 +1,160 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2008 Red Hat, Inc., Eric Paris + */ + +#include +#include +#include +#include +#include +#include +#include + +#include +#include "fsnotify.h" + +#include + +/* + * Final freeing of a group + */ +static void fsnotify_final_destroy_group(struct fsnotify_group *group) +{ + if (group->ops->free_group_priv) + group->ops->free_group_priv(group); + + mem_cgroup_put(group->memcg); + mutex_destroy(&group->mark_mutex); + + kfree(group); +} + +/* + * Stop queueing new events for this group. Once this function returns + * fsnotify_add_event() will not add any new events to the group's queue. + */ +void fsnotify_group_stop_queueing(struct fsnotify_group *group) +{ + spin_lock(&group->notification_lock); + group->shutdown = true; + spin_unlock(&group->notification_lock); +} + +/* + * Trying to get rid of a group. Remove all marks, flush all events and release + * the group reference. + * Note that another thread calling fsnotify_clear_marks_by_group() may still + * hold a ref to the group. + */ +void fsnotify_destroy_group(struct fsnotify_group *group) +{ + /* + * Stop queueing new events. The code below is careful enough to not + * require this but fanotify needs to stop queuing events even before + * fsnotify_destroy_group() is called and this makes the other callers + * of fsnotify_destroy_group() to see the same behavior. + */ + fsnotify_group_stop_queueing(group); + + /* Clear all marks for this group and queue them for destruction */ + fsnotify_clear_marks_by_group(group, FSNOTIFY_OBJ_TYPE_ANY); + + /* + * Some marks can still be pinned when waiting for response from + * userspace. Wait for those now. fsnotify_prepare_user_wait() will + * not succeed now so this wait is race-free. + */ + wait_event(group->notification_waitq, !atomic_read(&group->user_waits)); + + /* + * Wait until all marks get really destroyed. We could actually destroy + * them ourselves instead of waiting for worker to do it, however that + * would be racy as worker can already be processing some marks before + * we even entered fsnotify_destroy_group(). + */ + fsnotify_wait_marks_destroyed(); + + /* + * Since we have waited for fsnotify_mark_srcu in + * fsnotify_mark_destroy_list() there can be no outstanding event + * notification against this group. So clearing the notification queue + * of all events is reliable now. + */ + fsnotify_flush_notify(group); + + /* + * Destroy overflow event (we cannot use fsnotify_destroy_event() as + * that deliberately ignores overflow events. + */ + if (group->overflow_event) + group->ops->free_event(group, group->overflow_event); + + fsnotify_put_group(group); +} + +/* + * Get reference to a group. + */ +void fsnotify_get_group(struct fsnotify_group *group) +{ + refcount_inc(&group->refcnt); +} + +/* + * Drop a reference to a group. Free it if it's through. + */ +void fsnotify_put_group(struct fsnotify_group *group) +{ + if (refcount_dec_and_test(&group->refcnt)) + fsnotify_final_destroy_group(group); +} +EXPORT_SYMBOL_GPL(fsnotify_put_group); + +static struct fsnotify_group *__fsnotify_alloc_group( + const struct fsnotify_ops *ops, + int flags, gfp_t gfp) +{ + struct fsnotify_group *group; + + group = kzalloc_obj(struct fsnotify_group, gfp); + if (!group) + return ERR_PTR(-ENOMEM); + + /* set to 0 when there a no external references to this group */ + refcount_set(&group->refcnt, 1); + atomic_set(&group->user_waits, 0); + + spin_lock_init(&group->notification_lock); + INIT_LIST_HEAD(&group->notification_list); + init_waitqueue_head(&group->notification_waitq); + group->max_events = UINT_MAX; + + mutex_init(&group->mark_mutex); + INIT_LIST_HEAD(&group->marks_list); + + group->ops = ops; + group->flags = flags; + + return group; +} + +/* + * Create a new fsnotify_group and hold a reference for the group returned. + */ +struct fsnotify_group *fsnotify_alloc_group(const struct fsnotify_ops *ops, + int flags) +{ + gfp_t gfp = (flags & FSNOTIFY_GROUP_USER) ? GFP_KERNEL_ACCOUNT : + GFP_KERNEL; + + return __fsnotify_alloc_group(ops, flags, gfp); +} +EXPORT_SYMBOL_GPL(fsnotify_alloc_group); + +int fsnotify_fasync(int fd, struct file *file, int on) +{ + struct fsnotify_group *group = file->private_data; + + return fasync_helper(fd, file, on, &group->fsn_fa) >= 0 ? 0 : -EIO; +} -- cgit v1.3.1