[linux-2.6-block.git] / fs / 9p / cache.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * V9FS cache definitions.
 *
 *  Copyright (C) 2009 by Abhishek Kulkarni <adkulkar@umail.iu.edu>
 */

#include <linux/jiffies.h>
#include <linux/file.h>
#include <linux/slab.h>
#include <linux/stat.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <net/9p/9p.h>

#include "v9fs.h"
#include "cache.h"

int v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses,
				  const char *dev_name)
{
	struct fscache_volume *vcookie;
	char *name, *p;

	name = kasprintf(GFP_KERNEL, "9p,%s,%s",
			 dev_name, v9ses->cachetag ?: v9ses->aname);
	if (!name)
		return -ENOMEM;

	for (p = name; *p; p++)
		if (*p == '/')
			*p = ';';

	vcookie = fscache_acquire_volume(name, NULL, NULL, 0);
	p9_debug(P9_DEBUG_FSC, "session %p get volume %p (%s)\n",
		 v9ses, vcookie, name);
	if (IS_ERR(vcookie)) {
		if (vcookie != ERR_PTR(-EBUSY)) {
			kfree(name);
			return PTR_ERR(vcookie);
		}
		pr_err("Cache volume key already in use (%s)\n", name);
		vcookie = NULL;
	}
	v9ses->fscache = vcookie;
	kfree(name);
	return 0;
}

void v9fs_cache_inode_get_cookie(struct inode *inode)
{
	struct v9fs_inode *v9inode = V9FS_I(inode);
	struct v9fs_session_info *v9ses;
	__le32 version;
	__le64 path;

	if (!S_ISREG(inode->i_mode))
		return;
	if (WARN_ON(v9fs_inode_cookie(v9inode)))
		return;

	version = cpu_to_le32(v9inode->qid.version);
	path = cpu_to_le64(v9inode->qid.path);
	v9ses = v9fs_inode2v9ses(inode);
	v9inode->netfs.cache =
		fscache_acquire_cookie(v9fs_session_cache(v9ses),
				       0,
				       &path, sizeof(path),
				       &version, sizeof(version),
				       i_size_read(&v9inode->netfs.inode));
	if (v9inode->netfs.cache)
		mapping_set_release_always(inode->i_mapping);

	p9_debug(P9_DEBUG_FSC, "inode %p get cookie %p\n",
		 inode, v9fs_inode_cookie(v9inode));
}
Commit	Line	Data
	1	// SPDX-License-Identifier: GPL-2.0-only
	2	/*
	3	* V9FS cache definitions.
	4	*
	5	* Copyright (C) 2009 by Abhishek Kulkarni <adkulkar@umail.iu.edu>
	6	*/
	7
	8	#include <linux/jiffies.h>
	9	#include <linux/file.h>
	10	#include <linux/slab.h>
	11	#include <linux/stat.h>
	12	#include <linux/sched.h>
	13	#include <linux/fs.h>
	14	#include <net/9p/9p.h>
	15
	16	#include "v9fs.h"
	17	#include "cache.h"
	18
	19	int v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses,
	20	const char *dev_name)
	21	{
	22	struct fscache_volume *vcookie;
	23	char name, p;
	24
	25	name = kasprintf(GFP_KERNEL, "9p,%s,%s",
	26	dev_name, v9ses->cachetag ?: v9ses->aname);
	27	if (!name)
	28	return -ENOMEM;
	29
	30	for (p = name; *p; p++)
	31	if (*p == '/')
	32	*p = ';';
	33
	34	vcookie = fscache_acquire_volume(name, NULL, NULL, 0);
	35	p9_debug(P9_DEBUG_FSC, "session %p get volume %p (%s)\n",
	36	v9ses, vcookie, name);
	37	if (IS_ERR(vcookie)) {
	38	if (vcookie != ERR_PTR(-EBUSY)) {
	39	kfree(name);
	40	return PTR_ERR(vcookie);
	41	}
	42	pr_err("Cache volume key already in use (%s)\n", name);
	43	vcookie = NULL;
	44	}
	45	v9ses->fscache = vcookie;
	46	kfree(name);
	47	return 0;
	48	}
	49
	50	void v9fs_cache_inode_get_cookie(struct inode *inode)
	51	{
	52	struct v9fs_inode *v9inode = V9FS_I(inode);
	53	struct v9fs_session_info *v9ses;
	54	__le32 version;
	55	__le64 path;
	56
	57	if (!S_ISREG(inode->i_mode))
	58	return;
	59	if (WARN_ON(v9fs_inode_cookie(v9inode)))
	60	return;
	61
	62	version = cpu_to_le32(v9inode->qid.version);
	63	path = cpu_to_le64(v9inode->qid.path);
	64	v9ses = v9fs_inode2v9ses(inode);
	65	v9inode->netfs.cache =
	66	fscache_acquire_cookie(v9fs_session_cache(v9ses),
	67	0,
	68	&path, sizeof(path),
	69	&version, sizeof(version),
	70	i_size_read(&v9inode->netfs.inode));
	71	if (v9inode->netfs.cache)
	72	mapping_set_release_always(inode->i_mapping);
	73
	74	p9_debug(P9_DEBUG_FSC, "inode %p get cookie %p\n",
	75	inode, v9fs_inode_cookie(v9inode));
	76	}