forked from Minki/linux
6e195b0f7c
Sohaib Mohamed started a serie of tiny and incomplete checkpatch fixes but seemingly stopped halfway -- take over and do most of it. This is still missing net/9p/trans* and net/9p/protocol.c for a later time... Link: http://lkml.kernel.org/r/20211102134608.1588018-3-dominique.martinet@atmark-techno.com Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
202 lines
4.8 KiB
C
202 lines
4.8 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"
|
|
|
|
#define CACHETAG_LEN 11
|
|
|
|
struct fscache_netfs v9fs_cache_netfs = {
|
|
.name = "9p",
|
|
.version = 0,
|
|
};
|
|
|
|
/*
|
|
* v9fs_random_cachetag - Generate a random tag to be associated
|
|
* with a new cache session.
|
|
*
|
|
* The value of jiffies is used for a fairly randomly cache tag.
|
|
*/
|
|
|
|
static
|
|
int v9fs_random_cachetag(struct v9fs_session_info *v9ses)
|
|
{
|
|
v9ses->cachetag = kmalloc(CACHETAG_LEN, GFP_KERNEL);
|
|
if (!v9ses->cachetag)
|
|
return -ENOMEM;
|
|
|
|
return scnprintf(v9ses->cachetag, CACHETAG_LEN, "%lu", jiffies);
|
|
}
|
|
|
|
const struct fscache_cookie_def v9fs_cache_session_index_def = {
|
|
.name = "9P.session",
|
|
.type = FSCACHE_COOKIE_TYPE_INDEX,
|
|
};
|
|
|
|
void v9fs_cache_session_get_cookie(struct v9fs_session_info *v9ses)
|
|
{
|
|
/* If no cache session tag was specified, we generate a random one. */
|
|
if (!v9ses->cachetag) {
|
|
if (v9fs_random_cachetag(v9ses) < 0) {
|
|
v9ses->fscache = NULL;
|
|
kfree(v9ses->cachetag);
|
|
v9ses->cachetag = NULL;
|
|
return;
|
|
}
|
|
}
|
|
|
|
v9ses->fscache = fscache_acquire_cookie(v9fs_cache_netfs.primary_index,
|
|
&v9fs_cache_session_index_def,
|
|
v9ses->cachetag,
|
|
strlen(v9ses->cachetag),
|
|
NULL, 0,
|
|
v9ses, 0, true);
|
|
p9_debug(P9_DEBUG_FSC, "session %p get cookie %p\n",
|
|
v9ses, v9ses->fscache);
|
|
}
|
|
|
|
void v9fs_cache_session_put_cookie(struct v9fs_session_info *v9ses)
|
|
{
|
|
p9_debug(P9_DEBUG_FSC, "session %p put cookie %p\n",
|
|
v9ses, v9ses->fscache);
|
|
fscache_relinquish_cookie(v9ses->fscache, NULL, false);
|
|
v9ses->fscache = NULL;
|
|
}
|
|
|
|
static enum
|
|
fscache_checkaux v9fs_cache_inode_check_aux(void *cookie_netfs_data,
|
|
const void *buffer,
|
|
uint16_t buflen,
|
|
loff_t object_size)
|
|
{
|
|
const struct v9fs_inode *v9inode = cookie_netfs_data;
|
|
|
|
if (buflen != sizeof(v9inode->qid.version))
|
|
return FSCACHE_CHECKAUX_OBSOLETE;
|
|
|
|
if (memcmp(buffer, &v9inode->qid.version,
|
|
sizeof(v9inode->qid.version)))
|
|
return FSCACHE_CHECKAUX_OBSOLETE;
|
|
|
|
return FSCACHE_CHECKAUX_OKAY;
|
|
}
|
|
|
|
const struct fscache_cookie_def v9fs_cache_inode_index_def = {
|
|
.name = "9p.inode",
|
|
.type = FSCACHE_COOKIE_TYPE_DATAFILE,
|
|
.check_aux = v9fs_cache_inode_check_aux,
|
|
};
|
|
|
|
void v9fs_cache_inode_get_cookie(struct inode *inode)
|
|
{
|
|
struct v9fs_inode *v9inode;
|
|
struct v9fs_session_info *v9ses;
|
|
|
|
if (!S_ISREG(inode->i_mode))
|
|
return;
|
|
|
|
v9inode = V9FS_I(inode);
|
|
if (v9inode->fscache)
|
|
return;
|
|
|
|
v9ses = v9fs_inode2v9ses(inode);
|
|
v9inode->fscache = fscache_acquire_cookie(v9ses->fscache,
|
|
&v9fs_cache_inode_index_def,
|
|
&v9inode->qid.path,
|
|
sizeof(v9inode->qid.path),
|
|
&v9inode->qid.version,
|
|
sizeof(v9inode->qid.version),
|
|
v9inode,
|
|
i_size_read(&v9inode->vfs_inode),
|
|
true);
|
|
|
|
p9_debug(P9_DEBUG_FSC, "inode %p get cookie %p\n",
|
|
inode, v9inode->fscache);
|
|
}
|
|
|
|
void v9fs_cache_inode_put_cookie(struct inode *inode)
|
|
{
|
|
struct v9fs_inode *v9inode = V9FS_I(inode);
|
|
|
|
if (!v9inode->fscache)
|
|
return;
|
|
p9_debug(P9_DEBUG_FSC, "inode %p put cookie %p\n",
|
|
inode, v9inode->fscache);
|
|
|
|
fscache_relinquish_cookie(v9inode->fscache, &v9inode->qid.version,
|
|
false);
|
|
v9inode->fscache = NULL;
|
|
}
|
|
|
|
void v9fs_cache_inode_flush_cookie(struct inode *inode)
|
|
{
|
|
struct v9fs_inode *v9inode = V9FS_I(inode);
|
|
|
|
if (!v9inode->fscache)
|
|
return;
|
|
p9_debug(P9_DEBUG_FSC, "inode %p flush cookie %p\n",
|
|
inode, v9inode->fscache);
|
|
|
|
fscache_relinquish_cookie(v9inode->fscache, NULL, true);
|
|
v9inode->fscache = NULL;
|
|
}
|
|
|
|
void v9fs_cache_inode_set_cookie(struct inode *inode, struct file *filp)
|
|
{
|
|
struct v9fs_inode *v9inode = V9FS_I(inode);
|
|
|
|
if (!v9inode->fscache)
|
|
return;
|
|
|
|
mutex_lock(&v9inode->fscache_lock);
|
|
|
|
if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
|
|
v9fs_cache_inode_flush_cookie(inode);
|
|
else
|
|
v9fs_cache_inode_get_cookie(inode);
|
|
|
|
mutex_unlock(&v9inode->fscache_lock);
|
|
}
|
|
|
|
void v9fs_cache_inode_reset_cookie(struct inode *inode)
|
|
{
|
|
struct v9fs_inode *v9inode = V9FS_I(inode);
|
|
struct v9fs_session_info *v9ses;
|
|
struct fscache_cookie *old;
|
|
|
|
if (!v9inode->fscache)
|
|
return;
|
|
|
|
old = v9inode->fscache;
|
|
|
|
mutex_lock(&v9inode->fscache_lock);
|
|
fscache_relinquish_cookie(v9inode->fscache, NULL, true);
|
|
|
|
v9ses = v9fs_inode2v9ses(inode);
|
|
v9inode->fscache = fscache_acquire_cookie(v9ses->fscache,
|
|
&v9fs_cache_inode_index_def,
|
|
&v9inode->qid.path,
|
|
sizeof(v9inode->qid.path),
|
|
&v9inode->qid.version,
|
|
sizeof(v9inode->qid.version),
|
|
v9inode,
|
|
i_size_read(&v9inode->vfs_inode),
|
|
true);
|
|
p9_debug(P9_DEBUG_FSC, "inode %p revalidating cookie old %p new %p\n",
|
|
inode, old, v9inode->fscache);
|
|
|
|
mutex_unlock(&v9inode->fscache_lock);
|
|
}
|