linux-imx

// SPDX-License-Identifier: GPL-2.0+

/*

 * inode.c - NILFS inode operations.

 *

 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.

 *

 * Written by Ryusuke Konishi.

 *

 */

​

#include <linux/buffer_head.h>

#include <linux/gfp.h>

#include <linux/mpage.h>

#include <linux/pagemap.h>

#include <linux/writeback.h>

#include <linux/uio.h>

#include "nilfs.h"

#include "btnode.h"

#include "segment.h"

#include "page.h"

#include "mdt.h"

#include "cpfile.h"

#include "ifile.h"

​

/**

 * struct nilfs_iget_args - arguments used during comparison between inodes

 * @ino: inode number

 * @cno: checkpoint number

 * @root: pointer on NILFS root object (mounted checkpoint)

 * @for_gc: inode for GC flag

 */

struct nilfs_iget_args {

    u64 ino;

    __u64 cno;

    struct nilfs_root *root;

    int for_gc;

};

​

static int nilfs_iget_test(struct inode *inode, void *opaque);

​

void nilfs_inode_add_blocks(struct inode *inode, int n)

{

    struct nilfs_root *root = NILFS_I(inode)->i_root;

​

    inode_add_bytes(inode, i_blocksize(inode) * n);

    if (root)

        atomic64_add(n, &root->blocks_count);

}

​

void nilfs_inode_sub_blocks(struct inode *inode, int n)

{

    struct nilfs_root *root = NILFS_I(inode)->i_root;

​

    inode_sub_bytes(inode, i_blocksize(inode) * n);

    if (root)

        atomic64_sub(n, &root->blocks_count);

}

​

/**

 * nilfs_get_block() - get a file block on the filesystem (callback function)

 * @inode - inode struct of the target file

 * @blkoff - file block number

 * @bh_result - buffer head to be mapped on

 * @create - indicate whether allocating the block or not when it has not

 *      been allocated yet.

 *

 * This function does not issue actual read request of the specified data

 * block. It is done by VFS.

 */

int nilfs_get_block(struct inode *inode, sector_t blkoff,

            struct buffer_head *bh_result, int create)

{

    struct nilfs_inode_info *ii = NILFS_I(inode);

    struct the_nilfs *nilfs = inode->i_sb->s_fs_info;

    __u64 blknum = 0;

    int err = 0, ret;

    unsigned int maxblocks = bh_result->b_size >> inode->i_blkbits;

​

    down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);

    ret = nilfs_bmap_lookup_contig(ii->i_bmap, blkoff, &blknum, maxblocks);

    up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);

    if (ret >= 0) { /* found */

        map_bh(bh_result, inode->i_sb, blknum);

        if (ret > 0)

            bh_result->b_size = (ret << inode->i_blkbits);

        goto out;

    }

    /* data block was not found */

    if (ret == -ENOENT && create) {

        struct nilfs_transaction_info ti;

​

        bh_result->b_blocknr = 0;