Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / fs / ncpfs / symlink.c

diff --git a/kernel/fs/ncpfs/symlink.c b/kernel/fs/ncpfs/symlink.c
new file mode 100644 (file)
index 0000000..421b6f9
--- /dev/null
+++ b/kernel/fs/ncpfs/symlink.c
@@ -0,0 +1,181 @@
+/*
+ *  linux/fs/ncpfs/symlink.c
+ *
+ *  Code for allowing symbolic links on NCPFS (i.e. NetWare)
+ *  Symbolic links are not supported on native NetWare, so we use an
+ *  infrequently-used flag (Sh) and store a two-word magic header in
+ *  the file to make sure we don't accidentally use a non-link file
+ *  as a link.
+ *
+ *  When using the NFS namespace, we set the mode to indicate a symlink and
+ *  don't bother with the magic numbers.
+ *
+ *  from linux/fs/ext2/symlink.c
+ *
+ *  Copyright (C) 1998-99, Frank A. Vorstenbosch
+ *
+ *  ncpfs symlink handling code
+ *  NLS support (c) 1999 Petr Vandrovec
+ *  Modified 2000 Ben Harris, University of Cambridge for NFS NS meta-info
+ *
+ */
+
+
+#include <asm/uaccess.h>
+
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/time.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/stat.h>
+#include "ncp_fs.h"
+
+/* these magic numbers must appear in the symlink file -- this makes it a bit
+   more resilient against the magic attributes being set on random files. */
+
+#define NCP_SYMLINK_MAGIC0     cpu_to_le32(0x6c6d7973)     /* "symlnk->" */
+#define NCP_SYMLINK_MAGIC1     cpu_to_le32(0x3e2d6b6e)
+
+/* ----- read a symbolic link ------------------------------------------ */
+
+static int ncp_symlink_readpage(struct file *file, struct page *page)
+{
+       struct inode *inode = page->mapping->host;
+       int error, length, len;
+       char *link, *rawlink;
+       char *buf = kmap(page);
+
+       error = -ENOMEM;
+       rawlink = kmalloc(NCP_MAX_SYMLINK_SIZE, GFP_KERNEL);
+       if (!rawlink)
+               goto fail;
+
+       if (ncp_make_open(inode,O_RDONLY))
+               goto failEIO;
+
+       error=ncp_read_kernel(NCP_SERVER(inode),NCP_FINFO(inode)->file_handle,
+                         0,NCP_MAX_SYMLINK_SIZE,rawlink,&length);
+
+       ncp_inode_close(inode);
+       /* Close file handle if no other users... */
+       ncp_make_closed(inode);
+       if (error)
+               goto failEIO;
+
+       if (NCP_FINFO(inode)->flags & NCPI_KLUDGE_SYMLINK) {
+               if (length<NCP_MIN_SYMLINK_SIZE || 
+                   ((__le32 *)rawlink)[0]!=NCP_SYMLINK_MAGIC0 ||
+                   ((__le32 *)rawlink)[1]!=NCP_SYMLINK_MAGIC1)
+                       goto failEIO;
+               link = rawlink + 8;
+               length -= 8;
+       } else {
+               link = rawlink;
+       }
+
+       len = NCP_MAX_SYMLINK_SIZE;
+       error = ncp_vol2io(NCP_SERVER(inode), buf, &len, link, length, 0);
+       kfree(rawlink);
+       if (error)
+               goto fail;
+       SetPageUptodate(page);
+       kunmap(page);
+       unlock_page(page);
+       return 0;
+
+failEIO:
+       error = -EIO;
+       kfree(rawlink);
+fail:
+       SetPageError(page);
+       kunmap(page);
+       unlock_page(page);
+       return error;
+}
+
+/*
+ * symlinks can't do much...
+ */
+const struct address_space_operations ncp_symlink_aops = {
+       .readpage       = ncp_symlink_readpage,
+};
+       
+/* ----- create a new symbolic link -------------------------------------- */
+ 
+int ncp_symlink(struct inode *dir, struct dentry *dentry, const char *symname) {
+       struct inode *inode;
+       char *rawlink;
+       int length, err, i, outlen;
+       int kludge;
+       umode_t mode;
+       __le32 attr;
+       unsigned int hdr;
+
+       ncp_dbg(1, "dir=%p, dentry=%p, symname=%s\n", dir, dentry, symname);
+
+       if (ncp_is_nfs_extras(NCP_SERVER(dir), NCP_FINFO(dir)->volNumber))
+               kludge = 0;
+       else
+#ifdef CONFIG_NCPFS_EXTRAS
+       if (NCP_SERVER(dir)->m.flags & NCP_MOUNT_SYMLINKS)
+               kludge = 1;
+       else
+#endif
+       /* EPERM is returned by VFS if symlink procedure does not exist */
+               return -EPERM;
+  
+       rawlink = kmalloc(NCP_MAX_SYMLINK_SIZE, GFP_KERNEL);
+       if (!rawlink)
+               return -ENOMEM;
+
+       if (kludge) {
+               mode = 0;
+               attr = aSHARED | aHIDDEN;
+               ((__le32 *)rawlink)[0]=NCP_SYMLINK_MAGIC0;
+               ((__le32 *)rawlink)[1]=NCP_SYMLINK_MAGIC1;
+               hdr = 8;
+       } else {
+               mode = S_IFLNK | S_IRWXUGO;
+               attr = 0;
+               hdr = 0;
+       }                       
+
+       length = strlen(symname);
+       /* map to/from server charset, do not touch upper/lower case as
+          symlink can point out of ncp filesystem */
+       outlen = NCP_MAX_SYMLINK_SIZE - hdr;
+       err = ncp_io2vol(NCP_SERVER(dir), rawlink + hdr, &outlen, symname, length, 0);
+       if (err)
+               goto failfree;
+
+       outlen += hdr;
+
+       err = -EIO;
+       if (ncp_create_new(dir,dentry,mode,0,attr)) {
+               goto failfree;
+       }
+
+       inode=d_inode(dentry);
+
+       if (ncp_make_open(inode, O_WRONLY))
+               goto failfree;
+
+       if (ncp_write_kernel(NCP_SERVER(inode), NCP_FINFO(inode)->file_handle, 
+                            0, outlen, rawlink, &i) || i!=outlen) {
+               goto fail;
+       }
+
+       ncp_inode_close(inode);
+       ncp_make_closed(inode);
+       kfree(rawlink);
+       return 0;
+fail:;
+       ncp_inode_close(inode);
+       ncp_make_closed(inode);
+failfree:;
+       kfree(rawlink);
+       return err;
+}
+
+/* ----- EOF ----- */