Revision a9c9a6f741cdaa2fa9ba24a790db8d07295761e3 authored by Linus Torvalds on 02 September 2021, 22:09:46 UTC, committed by Linus Torvalds on 02 September 2021, 22:09:46 UTC
Pull SCSI updates from James Bottomley:
 "This series consists of the usual driver updates (ufs, qla2xxx,
  target, smartpqi, lpfc, mpt3sas).

  The core change causing the most churn was replacing the command
  request field request with a macro, allowing us to offset map to it
  and remove the redundant field; the same was also done for the tag
  field.

  The most impactful change is the final removal of scsi_ioctl, which
  has been deprecated for over a decade"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (293 commits)
  scsi: ufs: Fix ufshcd_request_sense_async() for Samsung KLUFG8RHDA-B2D1
  scsi: ufs: ufs-exynos: Fix static checker warning
  scsi: mpt3sas: Use the proper SCSI midlayer interfaces for PI
  scsi: lpfc: Use the proper SCSI midlayer interfaces for PI
  scsi: lpfc: Copyright updates for 14.0.0.1 patches
  scsi: lpfc: Update lpfc version to 14.0.0.1
  scsi: lpfc: Add bsg support for retrieving adapter cmf data
  scsi: lpfc: Add cmf_info sysfs entry
  scsi: lpfc: Add debugfs support for cm framework buffers
  scsi: lpfc: Add support for maintaining the cm statistics buffer
  scsi: lpfc: Add rx monitoring statistics
  scsi: lpfc: Add support for the CM framework
  scsi: lpfc: Add cmfsync WQE support
  scsi: lpfc: Add support for cm enablement buffer
  scsi: lpfc: Add cm statistics buffer support
  scsi: lpfc: Add EDC ELS support
  scsi: lpfc: Expand FPIN and RDF receive logging
  scsi: lpfc: Add MIB feature enablement support
  scsi: lpfc: Add SET_HOST_DATA mbox cmd to pass date/time info to firmware
  scsi: fc: Add EDC ELS definition
  ...
2 parent s 23852be + 9b5ac8a
Raw File
once.c
// SPDX-License-Identifier: GPL-2.0
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/once.h>
#include <linux/random.h>
#include <linux/module.h>

struct once_work {
	struct work_struct work;
	struct static_key_true *key;
	struct module *module;
};

static void once_deferred(struct work_struct *w)
{
	struct once_work *work;

	work = container_of(w, struct once_work, work);
	BUG_ON(!static_key_enabled(work->key));
	static_branch_disable(work->key);
	module_put(work->module);
	kfree(work);
}

static void once_disable_jump(struct static_key_true *key, struct module *mod)
{
	struct once_work *w;

	w = kmalloc(sizeof(*w), GFP_ATOMIC);
	if (!w)
		return;

	INIT_WORK(&w->work, once_deferred);
	w->key = key;
	w->module = mod;
	__module_get(mod);
	schedule_work(&w->work);
}

static DEFINE_SPINLOCK(once_lock);

bool __do_once_start(bool *done, unsigned long *flags)
	__acquires(once_lock)
{
	spin_lock_irqsave(&once_lock, *flags);
	if (*done) {
		spin_unlock_irqrestore(&once_lock, *flags);
		/* Keep sparse happy by restoring an even lock count on
		 * this lock. In case we return here, we don't call into
		 * __do_once_done but return early in the DO_ONCE() macro.
		 */
		__acquire(once_lock);
		return false;
	}

	return true;
}
EXPORT_SYMBOL(__do_once_start);

void __do_once_done(bool *done, struct static_key_true *once_key,
		    unsigned long *flags, struct module *mod)
	__releases(once_lock)
{
	*done = true;
	spin_unlock_irqrestore(&once_lock, *flags);
	once_disable_jump(once_key, mod);
}
EXPORT_SYMBOL(__do_once_done);
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