linux-kernel - [PATCH 8/8] rtc: class idr converted to ida and ida_simple

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1311352886-4047-18-git-send-email-jic23@cam.ac.uk>
Date:	Fri, 22 Jul 2011 17:41:26 +0100
From:	Jonathan Cameron <jic23@....ac.uk>
To:	linux-kernel@...r.kernel.org
Cc:	lm-sensors@...sensors.org, rtc-linux@...glegroups.com,
	osd-dev@...n-osd.org, linux-scsi@...r.kernel.org,
	dri-devel@...ts.freedesktop.org, jkosina@...e.cz, naota@...sp.net,
	rusty@...tcorp.com.au, paulmck@...ux.vnet.ibm.com,
	namhyung@...il.com, randy.dunlap@...cle.com, tj@...nel.org,
	cabarnes@...esign-llc.com, akpm@...ux-foundation.org,
	airlied@...hat.com, thellstrom@...are.com, johnpol@....mipt.ru,
	JBottomley@...allels.com, bhalevy@...asas.com,
	bharrosh@...asas.com, a.zummo@...ertech.it,
	guenter.roeck@...csson.com, khali@...ux-fr.org, airlied@...ux.ie,
	Jonathan Cameron <jic23@....ac.uk>
Subject: [PATCH 8/8] rtc: class idr converted to ida and ida_simple_get used.

This is the one use of an ida that doesn't retry on receiving -EAGAIN.
I'm assuming do so will cause no harm and may help on a rare occasion.

Signed-off-by: Jonathan Cameron <jic23@....ac.uk>
---
 drivers/rtc/class.c |   32 +++++++++-----------------------
 1 files changed, 9 insertions(+), 23 deletions(-)

diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c
index 4194e59..68ae46f 100644
--- a/drivers/rtc/class.c
+++ b/drivers/rtc/class.c
@@ -21,16 +21,13 @@
 #include "rtc-core.h"
 
 
-static DEFINE_IDR(rtc_idr);
-static DEFINE_MUTEX(idr_lock);
+static DEFINE_IDA(rtc_ida);
 struct class *rtc_class;
 
 static void rtc_device_release(struct device *dev)
 {
 	struct rtc_device *rtc = to_rtc_device(dev);
-	mutex_lock(&idr_lock);
-	idr_remove(&rtc_idr, rtc->id);
-	mutex_unlock(&idr_lock);
+	ida_simple_remove(&rtc_ida, rtc->id);
 	kfree(rtc);
 }
 
@@ -115,25 +112,16 @@ struct rtc_device *rtc_device_register(const char *name, struct device *dev,
 	struct rtc_wkalrm alrm;
 	int id, err;
 
-	if (idr_pre_get(&rtc_idr, GFP_KERNEL) == 0) {
-		err = -ENOMEM;
+	id = ida_simple_get(&rtc_ida, 0, 0, GFP_KERNEL);
+	if (id < 0) {
+		err = id;
 		goto exit;
 	}
 
-
-	mutex_lock(&idr_lock);
-	err = idr_get_new(&rtc_idr, NULL, &id);
-	mutex_unlock(&idr_lock);
-
-	if (err < 0)
-		goto exit;
-
-	id = id & MAX_ID_MASK;
-
 	rtc = kzalloc(sizeof(struct rtc_device), GFP_KERNEL);
 	if (rtc == NULL) {
 		err = -ENOMEM;
-		goto exit_idr;
+		goto exit_ida;
 	}
 
 	rtc->id = id;
@@ -191,10 +179,8 @@ struct rtc_device *rtc_device_register(const char *name, struct device *dev,
 exit_kfree:
 	kfree(rtc);
 
-exit_idr:
-	mutex_lock(&idr_lock);
-	idr_remove(&rtc_idr, id);
-	mutex_unlock(&idr_lock);
+exit_ida:
+	ida_simple_remove(&rtc_ida, id);
 
 exit:
 	dev_err(dev, "rtc core: unable to register %s, err = %d\n",
@@ -245,7 +231,7 @@ static void __exit rtc_exit(void)
 {
 	rtc_dev_exit();
 	class_destroy(rtc_class);
-	idr_destroy(&rtc_idr);
+	ida_destroy(&rtc_ida);
 }
 
 subsys_initcall(rtc_init);
-- 
1.7.3.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/