Re: [KJ][PATCH] Correct misc_register return code handling in several drivers

Neil Horman
2006-11-01T14:04:09Z

Hey all-
Since Andrew hasn't incorporated this patch yet, and I had the time, I
redid the patch taking Benjamin's INIT_LIST_HEAD and Joes mmtimer cleanup into
account. New patch attached, replacing the old one, everything except the
aforementioned cleanups is identical.

Thanks & Regards
Neil

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>

drivers/char/misc.c | 2 ++
drivers/char/mmtimer.c | 23 ++++++++++++++++++-----
drivers/char/tpm/tpm.c | 1 +
drivers/input/misc/hp_sdc_rtc.c | 4 +++-
drivers/macintosh/apm_emu.c | 3 ++-
5 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/drivers/char/misc.c b/drivers/char/misc.c
index 62ebe09..77c20f8 100644
--- a/drivers/char/misc.c
+++ b/drivers/char/misc.c
@@ -204,6 +204,8 @@ int misc_register(struct miscdevice * mi
dev_t dev;
int err = 0;

+ INIT_LIST_HEAD(&misc->list);
+
down(&misc_sem);
list_for_each_entry(c, &misc_list, list) {
if (c->minor == misc->minor) {
diff --git a/drivers/char/mmtimer.c b/drivers/char/mmtimer.c
index 22b9905..dbc5503 100644
--- a/drivers/char/mmtimer.c
+++ b/drivers/char/mmtimer.c
@@ -680,7 +680,7 @@ static int __init mmtimer_init(void)
if (sn_rtc_cycles_per_second < 100000) {
printk(KERN_ERR "%s: unable to determine clock frequency\n",
MMTIMER_NAME);
- return -1;
+ goto out1;
}

mmtimer_femtoperiod = ((unsigned long)1E15 + sn_rtc_cycles_per_second /
@@ -689,13 +689,13 @@ static int __init mmtimer_init(void)
if (request_irq(SGI_MMTIMER_VECTOR, mmtimer_interrupt, IRQF_PERCPU, MMTIMER_NAME, NULL)) {
printk(KERN_WARNING "%s: unable to allocate interrupt.",
MMTIMER_NAME);
- return -1;
+ goto out1;
}

if (misc_register(&mmtimer_miscdev)) {
printk(KERN_ERR "%s: failed to register device\n",
MMTIMER_NAME);
- return -1;
+ goto out2;
}

/* Get max numbered node, calculate slots needed */
@@ -709,16 +709,18 @@ static int __init mmtimer_init(void)
if (timers == NULL) {
printk(KERN_ERR "%s: failed to allocate memory for device\n",
MMTIMER_NAME);
- return -1;
+ goto out3;
}

+ memset(timers,0,(sizeof(mmtimer_t *)*maxn));
+
/* Allocate mmtimer_t's for each online node */
for_each_online_node(node) {
timers[node] = kmalloc_node(sizeof(mmtimer_t)*NUM_COMPARATORS, GFP_KERNEL, node);
if (timers[node] == NULL) {
printk(KERN_ERR "%s: failed to allocate memory for device\n",
MMTIMER_NAME);
- return -1;
+ goto out4;
}
for (i=0; i< NUM_COMPARATORS; i++) {
mmtimer_t * base = timers[node] + i;
@@ -739,6 +741,17 @@ static int __init mmtimer_init(void)
sn_rtc_cycles_per_second/(unsigned long)1E6);

return 0;
+
+out4:
+ for_each_online_node(node) {
+ kfree(timers[node]);
+ }
+out3:
+ misc_deregister(&mmtimer_miscdev);
+out2:
+ free_irq(SGI_MMTIMER_VECTOR, NULL);
+out1:
+ return -1;
}

module_init(mmtimer_init);
diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index 6ad2d3b..f14bf8b 100644
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -1155,6 +1155,7 @@ #define DEVNAME_SIZE 7

if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
list_del(&chip->list);
+ misc_deregister(&chip->vendor.miscdev);
put_device(dev);
clear_bit(chip->dev_num, dev_mask);
kfree(chip);
diff --git a/drivers/input/misc/hp_sdc_rtc.c b/drivers/input/misc/hp_sdc_rtc.c
index ab4da79..31d5a13 100644
--- a/drivers/input/misc/hp_sdc_rtc.c
+++ b/drivers/input/misc/hp_sdc_rtc.c
@@ -695,7 +695,9 @@ static int __init hp_sdc_rtc_init(void)

if ((ret = hp_sdc_request_timer_irq(&hp_sdc_rtc_isr)))
return ret;
- misc_register(&hp_sdc_rtc_dev);
+ if (misc_register(&hp_sdc_rtc_dev) != 0)
+ printk(KERN_INFO "Could not register misc. dev for i8042 rtc\n");
+
create_proc_read_entry ("driver/rtc", 0, NULL,
hp_sdc_rtc_read_proc, NULL);

diff --git a/drivers/macintosh/apm_emu.c b/drivers/macintosh/apm_emu.c
index 1293876..8862a83 100644
--- a/drivers/macintosh/apm_emu.c
+++ b/drivers/macintosh/apm_emu.c
@@ -529,7 +529,8 @@ static int __init apm_emu_init(void)
if (apm_proc)
apm_proc->owner = THIS_MODULE;

- misc_register(&apm_device);
+ if (misc_register(&apm_device) != 0)
+ printk(KERN_INFO "Could not create misc. device for apm\n");

pmu_register_sleep_notifier(&apm_sleep_notifier);

--
/***************************************************
*Neil Horman
*Software Engineer
*gpg keyid: 1024D / 0x92A74FA1 - http://pgp.mit.edu
***************************************************/