brintos

brintos / linux-shallow public Read only

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1// SPDX-License-Identifier: GPL-2.02/*3 * symlink.c4 *5 * Copyright (c) 1999 Al Smith6 *7 * Portions derived from work (c) 1995,1996 Christian Vogelgsang.8 */9 10#include <linux/string.h>11#include <linux/pagemap.h>12#include <linux/buffer_head.h>13#include "efs.h"14 15static int efs_symlink_read_folio(struct file *file, struct folio *folio)16{17	char *link = folio_address(folio);18	struct buffer_head *bh;19	struct inode *inode = folio->mapping->host;20	efs_block_t size = inode->i_size;21	int err;22  23	err = -ENAMETOOLONG;24	if (size > 2 * EFS_BLOCKSIZE)25		goto fail;26  27	/* read first 512 bytes of link target */28	err = -EIO;29	bh = sb_bread(inode->i_sb, efs_bmap(inode, 0));30	if (!bh)31		goto fail;32	memcpy(link, bh->b_data, (size > EFS_BLOCKSIZE) ? EFS_BLOCKSIZE : size);33	brelse(bh);34	if (size > EFS_BLOCKSIZE) {35		bh = sb_bread(inode->i_sb, efs_bmap(inode, 1));36		if (!bh)37			goto fail;38		memcpy(link + EFS_BLOCKSIZE, bh->b_data, size - EFS_BLOCKSIZE);39		brelse(bh);40	}41	link[size] = '\0';42	err = 0;43fail:44	folio_end_read(folio, err == 0);45	return err;46}47 48const struct address_space_operations efs_symlink_aops = {49	.read_folio	= efs_symlink_read_folio50};51