WSL2-Linux-Kernel/fs/freevxfs/vxfs_immed.c

59 строки
1.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2000-2001 Christoph Hellwig.
*/
/*
* Veritas filesystem driver - support for 'immed' inodes.
*/
#include <linux/fs.h>
#include <linux/pagemap.h>
#include "vxfs.h"
#include "vxfs_extern.h"
#include "vxfs_inode.h"
static int vxfs_immed_read_folio(struct file *, struct folio *);
/*
* Address space operations for immed files and directories.
*/
const struct address_space_operations vxfs_immed_aops = {
.read_folio = vxfs_immed_read_folio,
};
/**
* vxfs_immed_read_folio - read part of an immed inode into pagecache
* @file: file context (unused)
* @folio: folio to fill in.
*
* Description:
* vxfs_immed_read_folio reads a part of the immed area of the
* file that hosts @pp into the pagecache.
*
* Returns:
* Zero on success, else a negative error code.
*
* Locking status:
* @folio is locked and will be unlocked.
*/
static int
vxfs_immed_read_folio(struct file *fp, struct folio *folio)
{
struct page *pp = &folio->page;
struct vxfs_inode_info *vip = VXFS_INO(pp->mapping->host);
u_int64_t offset = (u_int64_t)pp->index << PAGE_SHIFT;
caddr_t kaddr;
kaddr = kmap(pp);
memcpy(kaddr, vip->vii_immed.vi_immed + offset, PAGE_SIZE);
kunmap(pp);
flush_dcache_page(pp);
SetPageUptodate(pp);
unlock_page(pp);
return 0;
}