Merge tag 'char-misc-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the large set of char/misc and other driver subsystem changes
  for 6.2-rc1. Nothing earth-shattering in here at all, just a lot of
  new driver development and minor fixes.

  Highlights include:

   - fastrpc driver updates

   - iio new drivers and updates

   - habanalabs driver updates for new hardware and features

   - slimbus driver updates

   - speakup module parameters added to aid in boot time configuration

   - i2c probe_new conversions for lots of different drivers

   - other small driver fixes and additions

  One semi-interesting change in here is the increase of the number of
  misc dynamic minors available to 1048448 to handle new huge-cpu
  systems.

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'char-misc-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (521 commits)
  extcon: usbc-tusb320: Convert to i2c's .probe_new()
  extcon: rt8973: Convert to i2c's .probe_new()
  extcon: fsa9480: Convert to i2c's .probe_new()
  extcon: max77843: Replace irqchip mask_invert with unmask_base
  chardev: fix error handling in cdev_device_add()
  mcb: mcb-parse: fix error handing in chameleon_parse_gdd()
  drivers: mcb: fix resource leak in mcb_probe()
  coresight: etm4x: fix repeated words in comments
  coresight: cti: Fix null pointer error on CTI init before ETM
  coresight: trbe: remove cpuhp instance node before remove cpuhp state
  counter: stm32-lptimer-cnt: fix the check on arr and cmp registers update
  misc: fastrpc: Add dma_mask to fastrpc_channel_ctx
  misc: fastrpc: Add mmap request assigning for static PD pool
  misc: fastrpc: Safekeep mmaps on interrupted invoke
  misc: fastrpc: Add support for audiopd
  misc: fastrpc: Rework fastrpc_req_munmap
  misc: fastrpc: Use fastrpc_map_put in fastrpc_map_create on fail
  misc: fastrpc: Add fastrpc_remote_heap_alloc
  misc: fastrpc: Add reserved mem support
  misc: fastrpc: Rename audio protection domain to root
  ...

1 files changed, 28 insertions, 13 deletions

diff --git a/drivers/char/misc.c b/drivers/char/misc.c
index cba19bfdc44d..05727f0daa6b 100644
--- a/drivers/char/misc.c
+++ b/drivers/char/misc.c
@@ -61,7 +61,29 @@ static DEFINE_MUTEX(misc_mtx);
  * Assigned numbers, used for dynamic minors
  */
 #define DYNAMIC_MINORS 128 /* like dynamic majors */
-static DECLARE_BITMAP(misc_minors, DYNAMIC_MINORS);
+static DEFINE_IDA(misc_minors_ida);
+
+static int misc_minor_alloc(void)
+{
+	int ret;
+
+	ret = ida_alloc_max(&misc_minors_ida, DYNAMIC_MINORS - 1, GFP_KERNEL);
+	if (ret >= 0) {
+		ret = DYNAMIC_MINORS - ret - 1;
+	} else {
+		ret = ida_alloc_range(&misc_minors_ida, MISC_DYNAMIC_MINOR + 1,
+				      MINORMASK, GFP_KERNEL);
+	}
+	return ret;
+}
+
+static void misc_minor_free(int minor)
+{
+	if (minor < DYNAMIC_MINORS)
+		ida_free(&misc_minors_ida, DYNAMIC_MINORS - minor - 1);
+	else if (minor > MISC_DYNAMIC_MINOR)
+		ida_free(&misc_minors_ida, minor);
+}
 
 #ifdef CONFIG_PROC_FS
 static void *misc_seq_start(struct seq_file *seq, loff_t *pos)
@@ -183,14 +205,13 @@ 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 = misc_minor_alloc();
 
-		if (i >= DYNAMIC_MINORS) {
+		if (i < 0) {
 			err = -EBUSY;
 			goto out;
 		}
-		misc->minor = DYNAMIC_MINORS - i - 1;
-		set_bit(i, misc_minors);
+		misc->minor = i;
 	} else {
 		struct miscdevice *c;
 
@@ -209,10 +230,7 @@ int misc_register(struct miscdevice *misc)
 					  misc, misc->groups, "%s", misc->name);
 	if (IS_ERR(misc->this_device)) {
 		if (is_dynamic) {
-			int i = DYNAMIC_MINORS - misc->minor - 1;
-
-			if (i < DYNAMIC_MINORS && i >= 0)
-				clear_bit(i, misc_minors);
+			misc_minor_free(misc->minor);
 			misc->minor = MISC_DYNAMIC_MINOR;
 		}
 		err = PTR_ERR(misc->this_device);
@@ -240,16 +258,13 @@ EXPORT_SYMBOL(misc_register);
 
 void misc_deregister(struct miscdevice *misc)
 {
-	int i = DYNAMIC_MINORS - misc->minor - 1;
-
 	if (WARN_ON(list_empty(&misc->list)))
 		return;
 
 	mutex_lock(&misc_mtx);
 	list_del(&misc->list);
 	device_destroy(misc_class, MKDEV(MISC_MAJOR, misc->minor));
-	if (i < DYNAMIC_MINORS && i >= 0)
-		clear_bit(i, misc_minors);
+	misc_minor_free(misc->minor);
 	mutex_unlock(&misc_mtx);
 }
 EXPORT_SYMBOL(misc_deregister);