1 /* 2 * symlink.c 3 * 4 * Copyright (c) 1999 Al Smith 5 * 6 * Portions derived from work (c) 1995,1996 Christian Vogelgsang. 7 */ 8 9 #include <linux/string.h> 10 #include <linux/pagemap.h> 11 #include <linux/buffer_head.h> 12 #include "efs.h" 13 14 static int efs_symlink_readpage(struct file *file, struct page *page) 15 { 16 char *link = kmap(page); 17 struct buffer_head * bh; 18 struct inode * inode = page->mapping->host; 19 efs_block_t size = inode->i_size; 20 int err; 21 22 err = -ENAMETOOLONG; 23 if (size > 2 * EFS_BLOCKSIZE) 24 goto fail; 25 26 /* read first 512 bytes of link target */ 27 err = -EIO; 28 bh = sb_bread(inode->i_sb, efs_bmap(inode, 0)); 29 if (!bh) 30 goto fail; 31 memcpy(link, bh->b_data, (size > EFS_BLOCKSIZE) ? EFS_BLOCKSIZE : size); 32 brelse(bh); 33 if (size > EFS_BLOCKSIZE) { 34 bh = sb_bread(inode->i_sb, efs_bmap(inode, 1)); 35 if (!bh) 36 goto fail; 37 memcpy(link + EFS_BLOCKSIZE, bh->b_data, size - EFS_BLOCKSIZE); 38 brelse(bh); 39 } 40 link[size] = '\0'; 41 SetPageUptodate(page); 42 kunmap(page); 43 unlock_page(page); 44 return 0; 45 fail: 46 SetPageError(page); 47 kunmap(page); 48 unlock_page(page); 49 return err; 50 } 51 52 const struct address_space_operations efs_symlink_aops = { 53 .readpage = efs_symlink_readpage 54 }; 55