59 строки
1.2 KiB
C
59 строки
1.2 KiB
C
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/*
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* symlink.c
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*
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* Copyright (c) 1999 Al Smith
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*
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* Portions derived from work (c) 1995,1996 Christian Vogelgsang.
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*/
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#include <linux/string.h>
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#include <linux/efs_fs.h>
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#include <linux/pagemap.h>
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#include <linux/buffer_head.h>
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#include <linux/smp_lock.h>
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static int efs_symlink_readpage(struct file *file, struct page *page)
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{
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char *link = kmap(page);
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struct buffer_head * bh;
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struct inode * inode = page->mapping->host;
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efs_block_t size = inode->i_size;
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int err;
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err = -ENAMETOOLONG;
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if (size > 2 * EFS_BLOCKSIZE)
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goto fail;
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lock_kernel();
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/* read first 512 bytes of link target */
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err = -EIO;
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bh = sb_bread(inode->i_sb, efs_bmap(inode, 0));
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if (!bh)
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goto fail;
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memcpy(link, bh->b_data, (size > EFS_BLOCKSIZE) ? EFS_BLOCKSIZE : size);
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brelse(bh);
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if (size > EFS_BLOCKSIZE) {
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bh = sb_bread(inode->i_sb, efs_bmap(inode, 1));
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if (!bh)
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goto fail;
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memcpy(link + EFS_BLOCKSIZE, bh->b_data, size - EFS_BLOCKSIZE);
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brelse(bh);
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}
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link[size] = '\0';
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unlock_kernel();
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SetPageUptodate(page);
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kunmap(page);
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unlock_page(page);
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return 0;
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fail:
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unlock_kernel();
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SetPageError(page);
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kunmap(page);
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unlock_page(page);
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return err;
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}
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struct address_space_operations efs_symlink_aops = {
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.readpage = efs_symlink_readpage
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};
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