IDR is deprecated in favor of XArray, which manages its own internal locking and provides a more consistent allocation API.
Convert tty_minors from an IDR to an allocating XArray. Update the error check in gb_uart_probe() from -ENOSPC to -EBUSY, since that is the error xa_alloc() returns when the allocation range is exhausted, unlike idr_alloc() which returned -ENOSPC.
Build-tested and verified via boot in QEMU: the module loads, registers with the greybus core, and unloads cleanly.
Signed-off-by: Dmitry Priz dimahtms@gmail.com --- drivers/staging/greybus/uart.c | 27 ++++++++++++++++----------- 1 file changed, 16 insertions(+), 11 deletions(-)
diff --git a/drivers/staging/greybus/uart.c b/drivers/staging/greybus/uart.c index 7d060b4cd33d..edd6b0e25c8c 100644 --- a/drivers/staging/greybus/uart.c +++ b/drivers/staging/greybus/uart.c @@ -22,7 +22,7 @@ #include <linux/serial.h> #include <linux/tty_driver.h> #include <linux/tty_flip.h> -#include <linux/idr.h> +#include <linux/xarray.h> #include <linux/fs.h> #include <linux/kdev_t.h> #include <linux/kfifo.h> @@ -67,7 +67,7 @@ struct gb_tty { };
static struct tty_driver *gb_tty_driver; -static DEFINE_IDR(tty_minors); +static DEFINE_XARRAY_ALLOC(tty_minors); static DEFINE_MUTEX(table_lock);
static int gb_uart_receive_data_handler(struct gb_operation *op) @@ -342,7 +342,7 @@ static struct gb_tty *get_gb_by_minor(unsigned int minor) struct gb_tty *gb_tty;
mutex_lock(&table_lock); - gb_tty = idr_find(&tty_minors, minor); + gb_tty = xa_load(&tty_minors, minor); if (gb_tty) { mutex_lock(&gb_tty->mutex); if (gb_tty->disconnected) { @@ -359,14 +359,19 @@ static struct gb_tty *get_gb_by_minor(unsigned int minor)
static int alloc_minor(struct gb_tty *gb_tty) { - int minor; + u32 id; + int ret;
mutex_lock(&table_lock); - minor = idr_alloc(&tty_minors, gb_tty, 0, GB_NUM_MINORS, GFP_KERNEL); + ret = xa_alloc(&tty_minors, &id, gb_tty, XA_LIMIT(0, GB_NUM_MINORS - 1), GFP_KERNEL); mutex_unlock(&table_lock); - if (minor >= 0) - gb_tty->minor = minor; - return minor; + + if (ret < 0) + return ret; + + gb_tty->minor = id; + + return id; }
static void release_minor(struct gb_tty *gb_tty) @@ -375,7 +380,7 @@ static void release_minor(struct gb_tty *gb_tty)
gb_tty->minor = 0; /* Maybe should use an invalid value instead */ mutex_lock(&table_lock); - idr_remove(&tty_minors, minor); + xa_erase(&tty_minors, minor); mutex_unlock(&table_lock); }
@@ -854,7 +859,7 @@ static int gb_uart_probe(struct gbphy_device *gbphy_dev,
minor = alloc_minor(gb_tty); if (minor < 0) { - if (minor == -ENOSPC) { + if (minor == -EBUSY) { dev_err(&gbphy_dev->dev, "no more free minor numbers\n"); retval = -ENODEV; @@ -984,7 +989,7 @@ static void gb_tty_exit(void) { tty_unregister_driver(gb_tty_driver); tty_driver_kref_put(gb_tty_driver); - idr_destroy(&tty_minors); + xa_destroy(&tty_minors); }
static const struct gbphy_device_id gb_uart_id_table[] = {