[PATCH] pktcdvd: add sysfs and debugfs interface
Add a sysfs and debugfs interface to the pktcdvd driver.
Look into the Documentation/ABI/testing/* files in the patch for more info.
Signed-off-by: Thomas Maier <balagi@justmail.de>
Signed-off-by: Peter Osterlund <petero2@telia.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index 91fbe7f..7c95c76 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -60,6 +60,8 @@
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_ioctl.h>
#include <scsi/scsi.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
#include <asm/uaccess.h>
@@ -89,6 +91,419 @@
static struct mutex ctl_mutex; /* Serialize open/close/setup/teardown */
static mempool_t *psd_pool;
+static struct class *class_pktcdvd = NULL; /* /sys/class/pktcdvd */
+static struct dentry *pkt_debugfs_root = NULL; /* /debug/pktcdvd */
+
+/* forward declaration */
+static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev);
+static int pkt_remove_dev(dev_t pkt_dev);
+static int pkt_seq_show(struct seq_file *m, void *p);
+
+
+
+/*
+ * create and register a pktcdvd kernel object.
+ */
+static struct pktcdvd_kobj* pkt_kobj_create(struct pktcdvd_device *pd,
+ const char* name,
+ struct kobject* parent,
+ struct kobj_type* ktype)
+{
+ struct pktcdvd_kobj *p;
+ p = kzalloc(sizeof(*p), GFP_KERNEL);
+ if (!p)
+ return NULL;
+ kobject_set_name(&p->kobj, "%s", name);
+ p->kobj.parent = parent;
+ p->kobj.ktype = ktype;
+ p->pd = pd;
+ if (kobject_register(&p->kobj) != 0)
+ return NULL;
+ return p;
+}
+/*
+ * remove a pktcdvd kernel object.
+ */
+static void pkt_kobj_remove(struct pktcdvd_kobj *p)
+{
+ if (p)
+ kobject_unregister(&p->kobj);
+}
+/*
+ * default release function for pktcdvd kernel objects.
+ */
+static void pkt_kobj_release(struct kobject *kobj)
+{
+ kfree(to_pktcdvdkobj(kobj));
+}
+
+
+/**********************************************************
+ *
+ * sysfs interface for pktcdvd
+ * by (C) 2006 Thomas Maier <balagi@justmail.de>
+ *
+ **********************************************************/
+
+#define DEF_ATTR(_obj,_name,_mode) \
+ static struct attribute _obj = { \
+ .name = _name, .owner = THIS_MODULE, .mode = _mode }
+
+/**********************************************************
+ /sys/class/pktcdvd/pktcdvd[0-7]/
+ stat/reset
+ stat/packets_started
+ stat/packets_finished
+ stat/kb_written
+ stat/kb_read
+ stat/kb_read_gather
+ write_queue/size
+ write_queue/congestion_off
+ write_queue/congestion_on
+ **********************************************************/
+
+DEF_ATTR(kobj_pkt_attr_st1, "reset", 0200);
+DEF_ATTR(kobj_pkt_attr_st2, "packets_started", 0444);
+DEF_ATTR(kobj_pkt_attr_st3, "packets_finished", 0444);
+DEF_ATTR(kobj_pkt_attr_st4, "kb_written", 0444);
+DEF_ATTR(kobj_pkt_attr_st5, "kb_read", 0444);
+DEF_ATTR(kobj_pkt_attr_st6, "kb_read_gather", 0444);
+
+static struct attribute *kobj_pkt_attrs_stat[] = {
+ &kobj_pkt_attr_st1,
+ &kobj_pkt_attr_st2,
+ &kobj_pkt_attr_st3,
+ &kobj_pkt_attr_st4,
+ &kobj_pkt_attr_st5,
+ &kobj_pkt_attr_st6,
+ NULL
+};
+
+DEF_ATTR(kobj_pkt_attr_wq1, "size", 0444);
+DEF_ATTR(kobj_pkt_attr_wq2, "congestion_off", 0644);
+DEF_ATTR(kobj_pkt_attr_wq3, "congestion_on", 0644);
+
+static struct attribute *kobj_pkt_attrs_wqueue[] = {
+ &kobj_pkt_attr_wq1,
+ &kobj_pkt_attr_wq2,
+ &kobj_pkt_attr_wq3,
+ NULL
+};
+
+/* declares a char buffer[64] _dbuf, copies data from
+ * _b with length _l into it and ensures that _dbuf ends
+ * with a \0 character.
+ */
+#define DECLARE_BUF_AS_STRING(_dbuf, _b, _l) \
+ char _dbuf[64]; int dlen = (_l) < 0 ? 0 : (_l); \
+ if (dlen >= sizeof(_dbuf)) dlen = sizeof(_dbuf)-1; \
+ memcpy(_dbuf, _b, dlen); _dbuf[dlen] = 0
+
+static ssize_t kobj_pkt_show(struct kobject *kobj,
+ struct attribute *attr, char *data)
+{
+ struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
+ int n = 0;
+ int v;
+ if (strcmp(attr->name, "packets_started") == 0) {
+ n = sprintf(data, "%lu\n", pd->stats.pkt_started);
+
+ } else if (strcmp(attr->name, "packets_finished") == 0) {
+ n = sprintf(data, "%lu\n", pd->stats.pkt_ended);
+
+ } else if (strcmp(attr->name, "kb_written") == 0) {
+ n = sprintf(data, "%lu\n", pd->stats.secs_w >> 1);
+
+ } else if (strcmp(attr->name, "kb_read") == 0) {
+ n = sprintf(data, "%lu\n", pd->stats.secs_r >> 1);
+
+ } else if (strcmp(attr->name, "kb_read_gather") == 0) {
+ n = sprintf(data, "%lu\n", pd->stats.secs_rg >> 1);
+
+ } else if (strcmp(attr->name, "size") == 0) {
+ spin_lock(&pd->lock);
+ v = pd->bio_queue_size;
+ spin_unlock(&pd->lock);
+ n = sprintf(data, "%d\n", v);
+
+ } else if (strcmp(attr->name, "congestion_off") == 0) {
+ spin_lock(&pd->lock);
+ v = pd->write_congestion_off;
+ spin_unlock(&pd->lock);
+ n = sprintf(data, "%d\n", v);
+
+ } else if (strcmp(attr->name, "congestion_on") == 0) {
+ spin_lock(&pd->lock);
+ v = pd->write_congestion_on;
+ spin_unlock(&pd->lock);
+ n = sprintf(data, "%d\n", v);
+ }
+ return n;
+}
+
+static void init_write_congestion_marks(int* lo, int* hi)
+{
+ if (*hi > 0) {
+ *hi = max(*hi, 500);
+ *hi = min(*hi, 1000000);
+ if (*lo <= 0)
+ *lo = *hi - 100;
+ else {
+ *lo = min(*lo, *hi - 100);
+ *lo = max(*lo, 100);
+ }
+ } else {
+ *hi = -1;
+ *lo = -1;
+ }
+}
+
+static ssize_t kobj_pkt_store(struct kobject *kobj,
+ struct attribute *attr,
+ const char *data, size_t len)
+{
+ struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
+ int val;
+ DECLARE_BUF_AS_STRING(dbuf, data, len); /* ensure sscanf scans a string */
+
+ if (strcmp(attr->name, "reset") == 0 && dlen > 0) {
+ pd->stats.pkt_started = 0;
+ pd->stats.pkt_ended = 0;
+ pd->stats.secs_w = 0;
+ pd->stats.secs_rg = 0;
+ pd->stats.secs_r = 0;
+
+ } else if (strcmp(attr->name, "congestion_off") == 0
+ && sscanf(dbuf, "%d", &val) == 1) {
+ spin_lock(&pd->lock);
+ pd->write_congestion_off = val;
+ init_write_congestion_marks(&pd->write_congestion_off,
+ &pd->write_congestion_on);
+ spin_unlock(&pd->lock);
+
+ } else if (strcmp(attr->name, "congestion_on") == 0
+ && sscanf(dbuf, "%d", &val) == 1) {
+ spin_lock(&pd->lock);
+ pd->write_congestion_on = val;
+ init_write_congestion_marks(&pd->write_congestion_off,
+ &pd->write_congestion_on);
+ spin_unlock(&pd->lock);
+ }
+ return len;
+}
+
+static struct sysfs_ops kobj_pkt_ops = {
+ .show = kobj_pkt_show,
+ .store = kobj_pkt_store
+};
+static struct kobj_type kobj_pkt_type_stat = {
+ .release = pkt_kobj_release,
+ .sysfs_ops = &kobj_pkt_ops,
+ .default_attrs = kobj_pkt_attrs_stat
+};
+static struct kobj_type kobj_pkt_type_wqueue = {
+ .release = pkt_kobj_release,
+ .sysfs_ops = &kobj_pkt_ops,
+ .default_attrs = kobj_pkt_attrs_wqueue
+};
+
+static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
+{
+ if (class_pktcdvd) {
+ pd->clsdev = class_device_create(class_pktcdvd,
+ NULL, pd->pkt_dev,
+ NULL, "%s", pd->name);
+ if (IS_ERR(pd->clsdev))
+ pd->clsdev = NULL;
+ }
+ if (pd->clsdev) {
+ pd->kobj_stat = pkt_kobj_create(pd, "stat",
+ &pd->clsdev->kobj,
+ &kobj_pkt_type_stat);
+ pd->kobj_wqueue = pkt_kobj_create(pd, "write_queue",
+ &pd->clsdev->kobj,
+ &kobj_pkt_type_wqueue);
+ }
+}
+
+static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
+{
+ pkt_kobj_remove(pd->kobj_stat);
+ pkt_kobj_remove(pd->kobj_wqueue);
+ if (class_pktcdvd)
+ class_device_destroy(class_pktcdvd, pd->pkt_dev);
+}
+
+
+/********************************************************************
+ /sys/class/pktcdvd/
+ add map block device
+ remove unmap packet dev
+ device_map show mappings
+ *******************************************************************/
+
+static void class_pktcdvd_release(struct class *cls)
+{
+ kfree(cls);
+}
+static ssize_t class_pktcdvd_show_map(struct class *c, char *data)
+{
+ int n = 0;
+ int idx;
+ mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
+ for (idx = 0; idx < MAX_WRITERS; idx++) {
+ struct pktcdvd_device *pd = pkt_devs[idx];
+ if (!pd)
+ continue;
+ n += sprintf(data+n, "%s %u:%u %u:%u\n",
+ pd->name,
+ MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
+ MAJOR(pd->bdev->bd_dev),
+ MINOR(pd->bdev->bd_dev));
+ }
+ mutex_unlock(&ctl_mutex);
+ return n;
+}
+
+static ssize_t class_pktcdvd_store_add(struct class *c, const char *buf,
+ size_t count)
+{
+ unsigned int major, minor;
+ DECLARE_BUF_AS_STRING(dbuf, buf, count);
+ if (sscanf(dbuf, "%u:%u", &major, &minor) == 2) {
+ pkt_setup_dev(MKDEV(major, minor), NULL);
+ return count;
+ }
+ return -EINVAL;
+}
+
+static ssize_t class_pktcdvd_store_remove(struct class *c, const char *buf,
+ size_t count)
+{
+ unsigned int major, minor;
+ DECLARE_BUF_AS_STRING(dbuf, buf, count);
+ if (sscanf(dbuf, "%u:%u", &major, &minor) == 2) {
+ pkt_remove_dev(MKDEV(major, minor));
+ return count;
+ }
+ return -EINVAL;
+}
+
+static struct class_attribute class_pktcdvd_attrs[] = {
+ __ATTR(add, 0200, NULL, class_pktcdvd_store_add),
+ __ATTR(remove, 0200, NULL, class_pktcdvd_store_remove),
+ __ATTR(device_map, 0444, class_pktcdvd_show_map, NULL),
+ __ATTR_NULL
+};
+
+
+static int pkt_sysfs_init(void)
+{
+ int ret = 0;
+
+ /*
+ * create control files in sysfs
+ * /sys/class/pktcdvd/...
+ */
+ class_pktcdvd = kzalloc(sizeof(*class_pktcdvd), GFP_KERNEL);
+ if (!class_pktcdvd)
+ return -ENOMEM;
+ class_pktcdvd->name = DRIVER_NAME;
+ class_pktcdvd->owner = THIS_MODULE;
+ class_pktcdvd->class_release = class_pktcdvd_release;
+ class_pktcdvd->class_attrs = class_pktcdvd_attrs;
+ ret = class_register(class_pktcdvd);
+ if (ret) {
+ kfree(class_pktcdvd);
+ class_pktcdvd = NULL;
+ printk(DRIVER_NAME": failed to create class pktcdvd\n");
+ return ret;
+ }
+ return 0;
+}
+
+static void pkt_sysfs_cleanup(void)
+{
+ if (class_pktcdvd)
+ class_destroy(class_pktcdvd);
+ class_pktcdvd = NULL;
+}
+
+/********************************************************************
+ entries in debugfs
+
+ /debugfs/pktcdvd[0-7]/
+ info
+
+ *******************************************************************/
+
+static int pkt_debugfs_seq_show(struct seq_file *m, void *p)
+{
+ return pkt_seq_show(m, p);
+}
+
+static int pkt_debugfs_fops_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, pkt_debugfs_seq_show, inode->i_private);
+}
+
+static struct file_operations debug_fops = {
+ .open = pkt_debugfs_fops_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+ .owner = THIS_MODULE,
+};
+
+static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
+{
+ if (!pkt_debugfs_root)
+ return;
+ pd->dfs_f_info = NULL;
+ pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
+ if (IS_ERR(pd->dfs_d_root)) {
+ pd->dfs_d_root = NULL;
+ return;
+ }
+ pd->dfs_f_info = debugfs_create_file("info", S_IRUGO,
+ pd->dfs_d_root, pd, &debug_fops);
+ if (IS_ERR(pd->dfs_f_info)) {
+ pd->dfs_f_info = NULL;
+ return;
+ }
+}
+
+static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
+{
+ if (!pkt_debugfs_root)
+ return;
+ if (pd->dfs_f_info)
+ debugfs_remove(pd->dfs_f_info);
+ pd->dfs_f_info = NULL;
+ if (pd->dfs_d_root)
+ debugfs_remove(pd->dfs_d_root);
+ pd->dfs_d_root = NULL;
+}
+
+static void pkt_debugfs_init(void)
+{
+ pkt_debugfs_root = debugfs_create_dir(DRIVER_NAME, NULL);
+ if (IS_ERR(pkt_debugfs_root)) {
+ pkt_debugfs_root = NULL;
+ return;
+ }
+}
+
+static void pkt_debugfs_cleanup(void)
+{
+ if (!pkt_debugfs_root)
+ return;
+ debugfs_remove(pkt_debugfs_root);
+ pkt_debugfs_root = NULL;
+}
+
+/* ----------------------------------------------------------*/
+
static void pkt_bio_finished(struct pktcdvd_device *pd)
{
@@ -2527,6 +2942,9 @@
add_disk(disk);
+ pkt_sysfs_dev_new(pd);
+ pkt_debugfs_dev_new(pd);
+
pkt_devs[idx] = pd;
if (pkt_dev)
*pkt_dev = pd->pkt_dev;
@@ -2577,6 +2995,11 @@
if (!IS_ERR(pd->cdrw.thread))
kthread_stop(pd->cdrw.thread);
+ pkt_devs[idx] = NULL;
+
+ pkt_debugfs_dev_remove(pd);
+ pkt_sysfs_dev_remove(pd);
+
blkdev_put(pd->bdev);
remove_proc_entry(pd->name, pkt_proc);
@@ -2586,7 +3009,6 @@
blk_cleanup_queue(pd->disk->queue);
put_disk(pd->disk);
- pkt_devs[idx] = NULL;
mempool_destroy(pd->rb_pool);
kfree(pd);
@@ -2670,6 +3092,8 @@
{
int ret;
+ mutex_init(&ctl_mutex);
+
psd_pool = mempool_create_kmalloc_pool(PSD_POOL_SIZE,
sizeof(struct packet_stacked_data));
if (!psd_pool)
@@ -2683,18 +3107,25 @@
if (!pktdev_major)
pktdev_major = ret;
+ ret = pkt_sysfs_init();
+ if (ret)
+ goto out;
+
+ pkt_debugfs_init();
+
ret = misc_register(&pkt_misc);
if (ret) {
printk(DRIVER_NAME": Unable to register misc device\n");
- goto out;
+ goto out_misc;
}
- mutex_init(&ctl_mutex);
-
pkt_proc = proc_mkdir(DRIVER_NAME, proc_root_driver);
return 0;
+out_misc:
+ pkt_debugfs_cleanup();
+ pkt_sysfs_cleanup();
out:
unregister_blkdev(pktdev_major, DRIVER_NAME);
out2:
@@ -2706,6 +3137,10 @@
{
remove_proc_entry(DRIVER_NAME, proc_root_driver);
misc_deregister(&pkt_misc);
+
+ pkt_debugfs_cleanup();
+ pkt_sysfs_cleanup();
+
unregister_blkdev(pktdev_major, DRIVER_NAME);
mempool_destroy(psd_pool);
}
