https://github.com/torvalds/linux
Revision 203fc3177dd7427a1f87ec33de201c6d67b5c5cb authored by Linus Torvalds on 24 May 2023, 18:31:37 UTC, committed by Linus Torvalds on 24 May 2023, 18:31:37 UTC
Pull MMC fixes from Ulf Hansson:
 "MMC core:

   - Fix error propagation for the non-block-device I/O paths

  MMC host:

   - sdhci-cadence: Fix an error path during probe

   - sdhci-esdhc-imx: Fix support for the 'no-mmc-hs400' DT property"

* tag 'mmc-v6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: sdhci-esdhc-imx: make "no-mmc-hs400" works
  mmc: sdhci-cadence: Fix an error handling path in sdhci_cdns_probe()
  mmc: block: ensure error propagation for non-blk
2 parent s 9d64600 + 81dce14
Raw File
Tip revision: 203fc3177dd7427a1f87ec33de201c6d67b5c5cb authored by Linus Torvalds on 24 May 2023, 18:31:37 UTC
Merge tag 'mmc-v6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc
Tip revision: 203fc31
drop_caches.c
// SPDX-License-Identifier: GPL-2.0
/*
 * Implement the manual drop-all-pagecache function
 */

#include <linux/pagemap.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/writeback.h>
#include <linux/sysctl.h>
#include <linux/gfp.h>
#include "internal.h"

/* A global variable is a bit ugly, but it keeps the code simple */
int sysctl_drop_caches;

static void drop_pagecache_sb(struct super_block *sb, void *unused)
{
	struct inode *inode, *toput_inode = NULL;

	spin_lock(&sb->s_inode_list_lock);
	list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
		spin_lock(&inode->i_lock);
		/*
		 * We must skip inodes in unusual state. We may also skip
		 * inodes without pages but we deliberately won't in case
		 * we need to reschedule to avoid softlockups.
		 */
		if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) ||
		    (mapping_empty(inode->i_mapping) && !need_resched())) {
			spin_unlock(&inode->i_lock);
			continue;
		}
		__iget(inode);
		spin_unlock(&inode->i_lock);
		spin_unlock(&sb->s_inode_list_lock);

		invalidate_mapping_pages(inode->i_mapping, 0, -1);
		iput(toput_inode);
		toput_inode = inode;

		cond_resched();
		spin_lock(&sb->s_inode_list_lock);
	}
	spin_unlock(&sb->s_inode_list_lock);
	iput(toput_inode);
}

int drop_caches_sysctl_handler(struct ctl_table *table, int write,
		void *buffer, size_t *length, loff_t *ppos)
{
	int ret;

	ret = proc_dointvec_minmax(table, write, buffer, length, ppos);
	if (ret)
		return ret;
	if (write) {
		static int stfu;

		if (sysctl_drop_caches & 1) {
			iterate_supers(drop_pagecache_sb, NULL);
			count_vm_event(DROP_PAGECACHE);
		}
		if (sysctl_drop_caches & 2) {
			drop_slab();
			count_vm_event(DROP_SLAB);
		}
		if (!stfu) {
			pr_info("%s (%d): drop_caches: %d\n",
				current->comm, task_pid_nr(current),
				sysctl_drop_caches);
		}
		stfu |= sysctl_drop_caches & 4;
	}
	return 0;
}
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