mirror_ubuntu-kernels/fs/9p/cache.c

77 lines
1.8 KiB
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));
}