root/fs/hpfs/file.c

DEFINITIONS

1. hpfs_file_release
2. hpfs_file_fsync
3. hpfs_bmap
4. hpfs_truncate
5. hpfs_get_block
6. hpfs_writepage
7. hpfs_readpage
8. hpfs_write_begin
9. _hpfs_bmap
10. hpfs_file_write

/*
 *  linux/fs/hpfs/file.c
 *
 *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
 *
 *  file VFS functions
 */

#include "hpfs_fn.h"

#define BLOCKS(size) (((size) + 511) >> 9)

static int hpfs_file_release(struct inode *inode, struct file *file)
{
        lock_kernel();
        hpfs_write_if_changed(inode);
        unlock_kernel();
        return 0;
}

int hpfs_file_fsync(struct file *file, struct dentry *dentry, int datasync)
{
        /*return file_fsync(file, dentry);*/
        return 0; /* Don't fsync :-) */
}

/*
 * generic_file_read often calls bmap with non-existing sector,
 * so we must ignore such errors.
 */

static secno hpfs_bmap(struct inode *inode, unsigned file_secno)
{
        struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
        unsigned n, disk_secno;
        struct fnode *fnode;
        struct buffer_head *bh;
        if (BLOCKS(hpfs_i(inode)->mmu_private) <= file_secno) return 0;
        n = file_secno - hpfs_inode->i_file_sec;
        if (n < hpfs_inode->i_n_secs) return hpfs_inode->i_disk_sec + n;
        if (!(fnode = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) return 0;
        disk_secno = hpfs_bplus_lookup(inode->i_sb, inode, &fnode->btree, file_secno, bh);
        if (disk_secno == -1) return 0;
        if (hpfs_chk_sectors(inode->i_sb, disk_secno, 1, "bmap")) return 0;
        return disk_secno;
}

static void hpfs_truncate(struct inode *i)
{
        if (IS_IMMUTABLE(i)) return /*-EPERM*/;
        lock_kernel();
        hpfs_i(i)->i_n_secs = 0;
        i->i_blocks = 1 + ((i->i_size + 511) >> 9);
        hpfs_i(i)->mmu_private = i->i_size;
        hpfs_truncate_btree(i->i_sb, i->i_ino, 1, ((i->i_size + 511) >> 9));
        hpfs_write_inode(i);
        hpfs_i(i)->i_n_secs = 0;
        unlock_kernel();
}

static int hpfs_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create)
{
        secno s;
        s = hpfs_bmap(inode, iblock);
        if (s) {
                map_bh(bh_result, inode->i_sb, s);
                return 0;
        }
        if (!create) return 0;
        if (iblock<<9 != hpfs_i(inode)->mmu_private) {
                BUG();
                return -EIO;
        }
        if ((s = hpfs_add_sector_to_btree(inode->i_sb, inode->i_ino, 1, inode->i_blocks - 1)) == -1) {
                hpfs_truncate_btree(inode->i_sb, inode->i_ino, 1, inode->i_blocks - 1);
                return -ENOSPC;
        }
        inode->i_blocks++;
        hpfs_i(inode)->mmu_private += 512;
        set_buffer_new(bh_result);
        map_bh(bh_result, inode->i_sb, s);
        return 0;
}

static int hpfs_writepage(struct page *page, struct writeback_control *wbc)
{
        return block_write_full_page(page,hpfs_get_block, wbc);
}

static int hpfs_readpage(struct file *file, struct page *page)
{
        return block_read_full_page(page,hpfs_get_block);
}

static int hpfs_write_begin(struct file *file, struct address_space *mapping,
                        loff_t pos, unsigned len, unsigned flags,
                        struct page **pagep, void **fsdata)
{
        *pagep = NULL;
        return cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
                                hpfs_get_block,
                                &hpfs_i(mapping->host)->mmu_private);
}

static sector_t _hpfs_bmap(struct address_space *mapping, sector_t block)
{
        return generic_block_bmap(mapping,block,hpfs_get_block);
}

const struct address_space_operations hpfs_aops = {
        .readpage = hpfs_readpage,
        .writepage = hpfs_writepage,
        .sync_page = block_sync_page,
        .write_begin = hpfs_write_begin,
        .write_end = generic_write_end,
        .bmap = _hpfs_bmap
};

static ssize_t hpfs_file_write(struct file *file, const char __user *buf,
                        size_t count, loff_t *ppos)
{
        ssize_t retval;

        retval = do_sync_write(file, buf, count, ppos);
        if (retval > 0)
                hpfs_i(file->f_path.dentry->d_inode)->i_dirty = 1;
        return retval;
}

const struct file_operations hpfs_file_ops =
{
        .llseek         = generic_file_llseek,
        .read           = do_sync_read,
        .aio_read       = generic_file_aio_read,
        .write          = hpfs_file_write,
        .aio_write      = generic_file_aio_write,
        .mmap           = generic_file_mmap,
        .release        = hpfs_file_release,
        .fsync          = hpfs_file_fsync,
        .splice_read    = generic_file_splice_read,
};

const struct inode_operations hpfs_file_iops =
{
        .truncate       = hpfs_truncate,
        .setattr        = hpfs_notify_change,
};