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/*
* Symlink inode operations for Coda filesystem
* Original version: (C) 1996 P. Braam and M. Callahan
* Rewritten for Linux 2.1. (C) 1997 Carnegie Mellon University
*
* Carnegie Mellon encourages users to contribute improvements to
* the Coda project. Contact Peter Braam (coda@cs.cmu.edu).
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/stat.h>
#include <linux/errno.h>
#include <linux/locks.h>
#include <asm/segment.h>
#include <asm/uaccess.h>
#include <linux/string.h>
#include <linux/coda.h>
#include <linux/coda_linux.h>
#include <linux/coda_psdev.h>
#include <linux/coda_fs_i.h>
#include <linux/coda_cache.h>
#include <linux/coda_proc.h>
static int coda_readlink(struct dentry *de, char *buffer, int length);
static struct dentry *coda_follow_link(struct dentry *, struct dentry *,
unsigned int);
struct inode_operations coda_symlink_inode_operations = {
NULL, /* no file-operations */
NULL, /* create */
NULL, /* lookup */
NULL, /* link */
NULL, /* unlink */
NULL, /* symlink */
NULL, /* mkdir */
NULL, /* rmdir */
NULL, /* mknod */
NULL, /* rename */
coda_readlink, /* readlink */
coda_follow_link, /* follow_link */
NULL, /* readpage */
NULL, /* writepage */
NULL, /* bmap */
NULL, /* truncate */
NULL, /* permission */
NULL, /* smap */
NULL, /* update page */
NULL /* revalidate */
};
static int coda_readlink(struct dentry *de, char *buffer, int length)
{
struct inode *inode = de->d_inode;
int len;
int error;
char *buf;
struct coda_inode_info *cp;
ENTRY;
cp = ITOC(inode);
coda_vfs_stat.readlink++;
/* the maximum length we receive is len */
if ( length > CODA_MAXPATHLEN )
len = CODA_MAXPATHLEN;
else
len = length;
CODA_ALLOC(buf, char *, len);
if ( !buf )
return -ENOMEM;
error = venus_readlink(inode->i_sb, &(cp->c_fid), buf, &len);
CDEBUG(D_INODE, "result %s\n", buf);
if (! error) {
copy_to_user(buffer, buf, len);
put_user('\0', buffer + len);
error = len;
}
if ( buf )
CODA_FREE(buf, len);
return error;
}
static struct dentry *coda_follow_link(struct dentry *de, struct dentry *base,
unsigned int follow)
{
struct inode *inode = de->d_inode;
int error;
struct coda_inode_info *cnp;
unsigned int len;
char mem[CODA_MAXPATHLEN];
char *path;
ENTRY;
CDEBUG(D_INODE, "(%x/%ld)\n", inode->i_dev, inode->i_ino);
cnp = ITOC(inode);
coda_vfs_stat.follow_link++;
len = CODA_MAXPATHLEN;
error = venus_readlink(inode->i_sb, &(cnp->c_fid), mem, &len);
if (error) {
dput(base);
return ERR_PTR(error);
}
len = strlen(mem);
path = kmalloc(len + 1, GFP_KERNEL);
if (!path) {
dput(base);
return ERR_PTR(-ENOMEM);
}
memcpy(path, mem, len);
path[len] = 0;
base = lookup_dentry(path, base, follow);
kfree(path);
return base;
}
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