From: Varsha Rao <rvarsha016@gmail.com>
To: Matthew Wilcox <mawilcox@microsoft.com>,
Arnd Bergmann <arnd@arndb.de>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH 5/5] drivers: char: Replace bit operation functions with IDA allocator.
Date: Fri, 7 Apr 2017 17:04:41 +0530 [thread overview]
Message-ID: <58e77955.09c3620a.bb125.3e20@mx.google.com> (raw)
In-Reply-To: <cover.1491563538.git.rvarsha016@gmail.com>
Replace bit operation functions with IDA allocator functions. As IDA
allocation is simpler.
Signed-off-by: Varsha Rao <rvarsha016@gmail.com>
---
drivers/char/misc.c | 16 ++++++++++------
1 file changed, 10 insertions(+), 6 deletions(-)
diff --git a/drivers/char/misc.c b/drivers/char/misc.c
index c9cd1ea..5786281 100644
--- a/drivers/char/misc.c
+++ b/drivers/char/misc.c
@@ -60,7 +60,7 @@ static DEFINE_MUTEX(misc_mtx);
* Assigned numbers, used for dynamic minors
*/
#define DYNAMIC_MINORS 64 /* like dynamic majors */
-static DECLARE_BITMAP(misc_minors, DYNAMIC_MINORS);
+static DEFINE_IDA(misc_minors_ida);
#ifdef CONFIG_PROC_FS
static void *misc_seq_start(struct seq_file *seq, loff_t *pos)
@@ -193,14 +193,18 @@ int misc_register(struct miscdevice *misc)
mutex_lock(&misc_mtx);
if (is_dynamic) {
- int i = find_first_zero_bit(misc_minors, DYNAMIC_MINORS);
+ int i = ida_simple_get(&misc_minors_ida, 0,
+ DYNAMIC_MINORS, GFP_KERNEL);
if (i >= DYNAMIC_MINORS) {
err = -EBUSY;
goto out;
- }
+ } else if (i < 0) {
+ err = i;
+ goto out;
+ } else {
misc->minor = DYNAMIC_MINORS - i - 1;
- set_bit(i, misc_minors);
+ }
} else {
struct miscdevice *c;
@@ -222,7 +226,7 @@ int misc_register(struct miscdevice *misc)
int i = DYNAMIC_MINORS - misc->minor - 1;
if (i < DYNAMIC_MINORS && i >= 0)
- clear_bit(i, misc_minors);
+ ida_simple_remove(&misc_minors_ida, i);
misc->minor = MISC_DYNAMIC_MINOR;
}
err = PTR_ERR(misc->this_device);
@@ -258,7 +262,7 @@ void misc_deregister(struct miscdevice *misc)
list_del(&misc->list);
device_destroy(misc_class, MKDEV(MISC_MAJOR, misc->minor));
if (i < DYNAMIC_MINORS && i >= 0)
- clear_bit(i, misc_minors);
+ ida_simple_remove(&misc_minors_ida, i);
mutex_unlock(&misc_mtx);
}
--
2.9.3
next prev parent reply other threads:[~2017-04-07 11:35 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <cover.1491563538.git.rvarsha016@gmail.com>
2017-04-07 11:28 ` [PATCH 1/5] drivers: char: Replace "foo * bar" with "foo *bar" Varsha Rao
2017-04-07 11:31 ` [PATCH 2/5] drivers: char: Add space after ',' Varsha Rao
2017-04-07 11:32 ` [PATCH 3/5] drivers: char: Add blank line after declaration Varsha Rao
2017-04-07 11:34 ` [PATCH 4/5] drivers: char: Replace printk with pr_err Varsha Rao
2017-04-07 15:46 ` Greg Kroah-Hartman
2017-04-07 11:34 ` Varsha Rao [this message]
2017-04-07 15:45 ` [PATCH 5/5] drivers: char: Replace bit operation functions with IDA allocator Greg Kroah-Hartman
[not found] ` <CAAFX7JSPg1s8qT5Qr=Z+QnuUYpjvyFr7T_Qf_3D08ecT3P65SQ@mail.gmail.com>
[not found] ` <CAAFX7JSQ349OQ1kAXqGX7ozRTWdqqDm6tC1FW1MbyvjR6h32Bw@mail.gmail.com>
2017-04-09 5:20 ` Varsha Rao
[not found] <cover.1491235332.git.rvarsha016@gmail.com>
2017-04-03 16:11 ` Varsha Rao
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