[PATCH 08/26] sd: Convert to new IDA interface

From: Matthew Wilcox
Date: Thu Jun 21 2018 - 17:30:02 EST


Allows us to remove an explicit spinlock.

Signed-off-by: Matthew Wilcox <willy@xxxxxxxxxxxxx>
---
drivers/scsi/sd.c | 21 ++++-----------------
1 file changed, 4 insertions(+), 17 deletions(-)

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 9421d9877730..8a493e64856c 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -123,7 +123,6 @@ static void scsi_disk_release(struct device *cdev);
static void sd_print_sense_hdr(struct scsi_disk *, struct scsi_sense_hdr *);
static void sd_print_result(const struct scsi_disk *, const char *, int);

-static DEFINE_SPINLOCK(sd_index_lock);
static DEFINE_IDA(sd_index_ida);

/* This semaphore is used to mediate the 0->1 reference get in the
@@ -3339,16 +3338,8 @@ static int sd_probe(struct device *dev)
if (!gd)
goto out_free;

- do {
- if (!ida_pre_get(&sd_index_ida, GFP_KERNEL))
- goto out_put;
-
- spin_lock(&sd_index_lock);
- error = ida_get_new(&sd_index_ida, &index);
- spin_unlock(&sd_index_lock);
- } while (error == -EAGAIN);
-
- if (error) {
+ index = ida_alloc(&sd_index_ida, GFP_KERNEL);
+ if (index < 0) {
sdev_printk(KERN_WARNING, sdp, "sd_probe: memory exhausted.\n");
goto out_put;
}
@@ -3392,9 +3383,7 @@ static int sd_probe(struct device *dev)
return 0;

out_free_index:
- spin_lock(&sd_index_lock);
- ida_remove(&sd_index_ida, index);
- spin_unlock(&sd_index_lock);
+ ida_free(&sd_index_ida, index);
out_put:
put_disk(gd);
out_free:
@@ -3459,9 +3448,7 @@ static void scsi_disk_release(struct device *dev)
struct scsi_disk *sdkp = to_scsi_disk(dev);
struct gendisk *disk = sdkp->disk;

- spin_lock(&sd_index_lock);
- ida_remove(&sd_index_ida, sdkp->index);
- spin_unlock(&sd_index_lock);
+ ida_free(&sd_index_ida, sdkp->index);

disk->private_data = NULL;
put_disk(disk);
--
2.17.1