140 строки
3.7 KiB
C
140 строки
3.7 KiB
C
/*
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* linux/fs/hpfs/file.c
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*
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* Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
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*
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* file VFS functions
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*/
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#include "hpfs_fn.h"
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#define BLOCKS(size) (((size) + 511) >> 9)
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static int hpfs_file_release(struct inode *inode, struct file *file)
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{
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lock_kernel();
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hpfs_write_if_changed(inode);
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unlock_kernel();
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return 0;
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}
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int hpfs_file_fsync(struct file *file, struct dentry *dentry, int datasync)
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{
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/*return file_fsync(file, dentry);*/
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return 0; /* Don't fsync :-) */
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}
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/*
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* generic_file_read often calls bmap with non-existing sector,
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* so we must ignore such errors.
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*/
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static secno hpfs_bmap(struct inode *inode, unsigned file_secno)
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{
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struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
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unsigned n, disk_secno;
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struct fnode *fnode;
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struct buffer_head *bh;
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if (BLOCKS(hpfs_i(inode)->mmu_private) <= file_secno) return 0;
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n = file_secno - hpfs_inode->i_file_sec;
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if (n < hpfs_inode->i_n_secs) return hpfs_inode->i_disk_sec + n;
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if (!(fnode = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) return 0;
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disk_secno = hpfs_bplus_lookup(inode->i_sb, inode, &fnode->btree, file_secno, bh);
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if (disk_secno == -1) return 0;
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if (hpfs_chk_sectors(inode->i_sb, disk_secno, 1, "bmap")) return 0;
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return disk_secno;
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}
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static void hpfs_truncate(struct inode *i)
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{
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if (IS_IMMUTABLE(i)) return /*-EPERM*/;
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lock_kernel();
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hpfs_i(i)->i_n_secs = 0;
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i->i_blocks = 1 + ((i->i_size + 511) >> 9);
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hpfs_i(i)->mmu_private = i->i_size;
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hpfs_truncate_btree(i->i_sb, i->i_ino, 1, ((i->i_size + 511) >> 9));
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hpfs_write_inode(i);
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hpfs_i(i)->i_n_secs = 0;
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unlock_kernel();
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}
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static int hpfs_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_result, int create)
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{
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secno s;
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s = hpfs_bmap(inode, iblock);
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if (s) {
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map_bh(bh_result, inode->i_sb, s);
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return 0;
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}
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if (!create) return 0;
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if (iblock<<9 != hpfs_i(inode)->mmu_private) {
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BUG();
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return -EIO;
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}
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if ((s = hpfs_add_sector_to_btree(inode->i_sb, inode->i_ino, 1, inode->i_blocks - 1)) == -1) {
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hpfs_truncate_btree(inode->i_sb, inode->i_ino, 1, inode->i_blocks - 1);
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return -ENOSPC;
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}
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inode->i_blocks++;
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hpfs_i(inode)->mmu_private += 512;
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set_buffer_new(bh_result);
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map_bh(bh_result, inode->i_sb, s);
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return 0;
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}
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static int hpfs_writepage(struct page *page, struct writeback_control *wbc)
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{
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return block_write_full_page(page,hpfs_get_block, wbc);
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}
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static int hpfs_readpage(struct file *file, struct page *page)
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{
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return block_read_full_page(page,hpfs_get_block);
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}
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static int hpfs_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to)
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{
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return cont_prepare_write(page,from,to,hpfs_get_block,
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&hpfs_i(page->mapping->host)->mmu_private);
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}
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static sector_t _hpfs_bmap(struct address_space *mapping, sector_t block)
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{
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return generic_block_bmap(mapping,block,hpfs_get_block);
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}
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const struct address_space_operations hpfs_aops = {
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.readpage = hpfs_readpage,
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.writepage = hpfs_writepage,
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.sync_page = block_sync_page,
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.prepare_write = hpfs_prepare_write,
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.commit_write = generic_commit_write,
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.bmap = _hpfs_bmap
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};
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static ssize_t hpfs_file_write(struct file *file, const char __user *buf,
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size_t count, loff_t *ppos)
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{
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ssize_t retval;
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retval = do_sync_write(file, buf, count, ppos);
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if (retval > 0)
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hpfs_i(file->f_path.dentry->d_inode)->i_dirty = 1;
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return retval;
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}
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const struct file_operations hpfs_file_ops =
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{
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.llseek = generic_file_llseek,
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.read = do_sync_read,
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.aio_read = generic_file_aio_read,
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.write = hpfs_file_write,
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.aio_write = generic_file_aio_write,
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.mmap = generic_file_mmap,
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.release = hpfs_file_release,
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.fsync = hpfs_file_fsync,
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.sendfile = generic_file_sendfile,
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};
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struct inode_operations hpfs_file_iops =
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{
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.truncate = hpfs_truncate,
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.setattr = hpfs_notify_change,
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};
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