patch-2.3.34 linux/fs/stat.c

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diff -u --recursive --new-file v2.3.33/linux/fs/stat.c linux/fs/stat.c
@@ -280,3 +280,124 @@
 	unlock_kernel();
 	return error;
 }
+
+
+/* ---------- LFS-64 ----------- */
+#if BITS_PER_LONG == 32
+
+static long cp_new_stat64(struct inode * inode, struct stat64 * statbuf)
+{
+	struct stat64 tmp;
+	unsigned int blocks, indirect;
+
+	memset(&tmp, 0, sizeof(tmp));
+	tmp.st_dev = kdev_t_to_nr(inode->i_dev);
+	tmp.st_ino = inode->i_ino;
+	tmp.st_mode = inode->i_mode;
+	tmp.st_nlink = inode->i_nlink;
+	tmp.st_uid = inode->i_uid;
+	tmp.st_gid = inode->i_gid;
+	tmp.st_rdev = kdev_t_to_nr(inode->i_rdev);
+	tmp.st_atime = inode->i_atime;
+	tmp.st_mtime = inode->i_mtime;
+	tmp.st_ctime = inode->i_ctime;
+	tmp.st_size = inode->i_size;
+/*
+ * st_blocks and st_blksize are approximated with a simple algorithm if
+ * they aren't supported directly by the filesystem. The minix and msdos
+ * filesystems don't keep track of blocks, so they would either have to
+ * be counted explicitly (by delving into the file itself), or by using
+ * this simple algorithm to get a reasonable (although not 100% accurate)
+ * value.
+ */
+
+/*
+ * Use minix fs values for the number of direct and indirect blocks.  The
+ * count is now exact for the minix fs except that it counts zero blocks.
+ * Everything is in units of BLOCK_SIZE until the assignment to
+ * tmp.st_blksize.
+ */
+#define D_B   7
+#define I_B   (BLOCK_SIZE / sizeof(unsigned short))
+
+	if (!inode->i_blksize) {
+		blocks = (tmp.st_size + BLOCK_SIZE - 1) >> BLOCK_SIZE_BITS;
+		if (blocks > D_B) {
+			indirect = (blocks - D_B + I_B - 1) / I_B;
+			blocks += indirect;
+			if (indirect > 1) {
+				indirect = (indirect - 1 + I_B - 1) / I_B;
+				blocks += indirect;
+				if (indirect > 1)
+					blocks++;
+			}
+		}
+		tmp.st_blocks = (BLOCK_SIZE / 512) * blocks;
+		tmp.st_blksize = BLOCK_SIZE;
+	} else {
+		tmp.st_blocks = inode->i_blocks;
+		tmp.st_blksize = inode->i_blksize;
+	}
+	return copy_to_user(statbuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
+}
+
+asmlinkage long sys_stat64(char * filename, struct stat64 * statbuf, long flags)
+{
+	struct dentry * dentry;
+	int error;
+
+	lock_kernel();
+	dentry = namei(filename);
+
+	error = PTR_ERR(dentry);
+	if (!IS_ERR(dentry)) {
+		error = do_revalidate(dentry);
+		if (!error)
+			error = cp_new_stat64(dentry->d_inode, statbuf);
+
+		dput(dentry);
+	}
+	unlock_kernel();
+	return error;
+}
+
+asmlinkage long sys_lstat64(char * filename, struct stat64 * statbuf, long flags)
+{
+	struct dentry * dentry;
+	int error;
+
+	lock_kernel();
+	dentry = lnamei(filename);
+
+	error = PTR_ERR(dentry);
+	if (!IS_ERR(dentry)) {
+		error = do_revalidate(dentry);
+		if (!error)
+			error = cp_new_stat64(dentry->d_inode, statbuf);
+
+		dput(dentry);
+	}
+	unlock_kernel();
+	return error;
+}
+
+asmlinkage long sys_fstat64(unsigned long fd, struct stat64 * statbuf, long flags)
+{
+	struct file * f;
+	int err = -EBADF;
+
+	lock_kernel();
+	f = fget(fd);
+	if (f) {
+		struct dentry * dentry = f->f_dentry;
+
+		err = do_revalidate(dentry);
+		if (!err)
+			err = cp_new_stat64(dentry->d_inode, statbuf);
+		fput(f);
+	}
+	unlock_kernel();
+	return err;
+}
+
+#endif /* BITS_PER_LONG == 32 */

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