mirror of
https://github.com/cirosantilli/linux-kernel-module-cheat.git
synced 2026-01-22 17:55:57 +01:00
56738a1c70
Unsquashed version at v2-rc-unsquashed, but that cannot be merged as it breaks bisects at several points. All bugs will not bisect to this humongous change. It all started with a conversion of the Bash scripts to Python, mainly because I couldn't stand not being able to properly use --options for run which has a million options. Then since that required a full testing, I decided to do all the refactorings that I had in mind at once, and so I did and it became v2-rc. This is the largest patch I have ever done! OMG a few weeks of extra time. I'm never writing a Bash script for anything that starts getting big again. Some of the features are: * separate build-qemu and build-gem5 commands * common: convert scripts to python. Add --option for everything * rename build to build-buildroot now that we are splitting all the build commands, Linux kernel to follow * move all git submodules to submodules/ and all buildroot packages to packages/ * refactor the out/ structure. Keep projects on toplevel, because guest projects separate archs and host ones don't, making a toplevel arch wrong * do-release: rename to just release https://stackoverflow.com/questions/16174992/cant-get-argparse-to-read-quoted-string-with-dashes-in-it * run: add --terminal and explain gem5 pdb * just track the lvimrc * store CLI kernel config fragment inside buildlroot to avoid conflicts * gem5: document m5 initparam * readme: make a bunch of things awesomer * readme: fix broken refs * parsec-benchmark: update to 75d55ac446a43c47efb1044844a108c6c330184c Could not fetch otherwise. * gem5: M5_OVERRIDE_PY_SOURCE
77 lines
1.7 KiB
C
77 lines
1.7 KiB
C
/* https://github.com/cirosantilli/linux-kernel-module-cheat#automatically-create-character-device-file-on-insmod */
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#include <linux/cdev.h>
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#include <linux/device.h>
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#include <linux/fs.h> /* register_chrdev, unregister_chrdev */
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#include <linux/module.h>
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#include <linux/seq_file.h> /* seq_read, seq_lseek, single_release */
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#define NAME "lkmc_character_device_create"
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static int major = -1;
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static struct cdev mycdev;
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static struct class *myclass = NULL;
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static int show(struct seq_file *m, void *v)
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{
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seq_printf(m, "abcd");
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return 0;
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}
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static int open(struct inode *inode, struct file *file)
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{
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return single_open(file, show, NULL);
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}
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static const struct file_operations fops = {
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.llseek = seq_lseek,
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.open = open,
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.owner = THIS_MODULE,
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.read = seq_read,
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.release = single_release,
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};
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static void cleanup(int device_created)
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{
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if (device_created) {
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device_destroy(myclass, major);
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cdev_del(&mycdev);
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}
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if (myclass)
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class_destroy(myclass);
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if (major != -1)
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unregister_chrdev_region(major, 1);
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}
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static int myinit(void)
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{
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int device_created = 0;
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/* cat /proc/devices */
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if (alloc_chrdev_region(&major, 0, 1, NAME "_proc") < 0)
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goto error;
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/* ls /sys/class */
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if ((myclass = class_create(THIS_MODULE, NAME "_sys")) == NULL)
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goto error;
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/* ls /dev/ */
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if (device_create(myclass, NULL, major, NULL, NAME "_dev") == NULL)
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goto error;
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device_created = 1;
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cdev_init(&mycdev, &fops);
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if (cdev_add(&mycdev, major, 1) == -1)
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goto error;
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return 0;
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error:
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cleanup(device_created);
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return -1;
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}
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static void myexit(void)
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{
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cleanup(1);
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}
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module_init(myinit)
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module_exit(myexit)
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MODULE_LICENSE("GPL");
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