seq_file: move doc to README

kernel_module/README.adoc

@@ -22,8 +22,6 @@
 .. link:ioctl.c[]
 .. link:mmap.c[]
 .. link:poll.c[]
-.. link:seq_file.c[]
-.. link:seq_file_inode.c[]
 . Asynchronous
 .. link:irq.c[]
 .. link:kthread.c[]

kernel_module/anonymous_inode.c

@@ -24,6 +24,9 @@ static ssize_t read(struct file *filp, char __user *buf, size_t len, loff_t *off
 		ret = -EFAULT;
 	}
 	myval <<= 4;
+	if (myval == 0) {
+		myval = 1;
+	}
 	return ret;
 }
 

kernel_module/seq_file.c

@@ -1,28 +1,4 @@
-/*
-Adapted from: Documentation/filesystems/seq_file.txt
-but we limit the count to the max module parameter.
-
-Writting trivial read fops is repetitive and error prone.
-
-The seq_file API makes the process much easier for those trivial cases.
-
-This example is behaves just like a file that contains:
-
-	0
-	1
-	2
-
-However, we only store a single integer in memory
-and calculate the file on the fly in an iterator fashion.
-
-There is not write version, as writes are more complex:
-https://stackoverflow.com/questions/30710517/how-to-implement-a-writable-proc-file-by-using-seq-file-in-a-driver-module
-
-Bibliography:
-
-- Documentation/filesystems/seq_file.txt
-- https://stackoverflow.com/questions/25399112/how-to-use-a-seq-file-in-linux-modules
-*/
+/* https://github.com/cirosantilli/linux-kernel-module-cheat#seq_file */
 
 #include <linux/debugfs.h>
 #include <linux/errno.h> /* EFAULT */

kernel_module/seq_file_single_open.c

@@ -1,12 +1,4 @@
-/*
-If you have the entire read output upfront, single_open
-is an even more convenient version of seq_file.
-
-This example behaves like a file that contains:
-
-	ab
-	cd
-*/
+/* https://github.com/cirosantilli/linux-kernel-module-cheat#seq_file-single_open */
 
 #include <linux/debugfs.h>
 #include <linux/errno.h> /* EFAULT */
@@ -40,8 +32,7 @@ static const struct file_operations fops = {
 
 static int myinit(void)
 {
-	debugfs_file = debugfs_create_file(
-		"lkmc_seq_file_single", S_IRUSR, NULL, NULL, &fops);
+	debugfs_file = debugfs_create_file("lkmc_seq_file_single_open", S_IRUSR, NULL, NULL, &fops);
 	return 0;
 }