// 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));
}