NFS client llseek

From: dzafman@kahuna.cag.cpqcorp.net
Date: Thu Dec 13 2001 - 19:51:00 EST


I noticed that generic_file_llseek looks at i_size without performing a
revalidate, so I propose the following patch for NFS client. It applies to
both 2.4.16 and 2.5.0 kernels.

diff -Naur linux-2.4.16.orig/fs/nfs/file.c linux-2.4.16/fs/nfs/file.c
--- linux-2.4.16.orig/fs/nfs/file.c Sun Sep 23 09:48:01 2001
+++ linux-2.4.16/fs/nfs/file.c Thu Dec 13 15:35:05 2001
@@ -39,9 +39,10 @@
 static ssize_t nfs_file_write(struct file *, const char *, size_t, loff_t *);
 static int nfs_file_flush(struct file *);
 static int nfs_fsync(struct file *, struct dentry *dentry, int datasync);
+static loff_t nfs_file_llseek(struct file *, loff_t, int origin);
 
 struct file_operations nfs_file_operations = {
- llseek: generic_file_llseek,
+ llseek: nfs_file_llseek,
         read: nfs_file_read,
         write: nfs_file_write,
         mmap: nfs_file_mmap,
@@ -142,6 +143,24 @@
         }
         unlock_kernel();
         return status;
+}
+
+static loff_t
+nfs_file_llseek(struct file *file, loff_t offset, int origin)
+{
+ struct dentry * dentry = file->f_dentry;
+ struct inode * inode = dentry->d_inode;
+ loff_t result;
+
+ /*
+ * Make sure inode fields are up-to-date, since generic_file_llseek()
+ * might look at anything in the inode. Currently, i_size may be
+ * used.
+ */
+ result = nfs_revalidate_inode(NFS_SERVER(inode), inode);
+ if (!result)
+ result = generic_file_llseek(file, offset, origin);
+ return result;
 }
 
 /*
-
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This archive was generated by hypermail 2b29 : Sat Dec 15 2001 - 21:00:27 EST