scsi: convert to idr_alloc()

Convert to the much saner new idr interface.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 34 insertions, 57 deletions

diff --git a/drivers/scsi/ch.c b/drivers/scsi/ch.c
index a15474eef5f7..2a323742ce04 100644
--- a/drivers/scsi/ch.c
+++ b/drivers/scsi/ch.c
@@ -895,7 +895,7 @@ static int ch_probe(struct device *dev)
 {
         struct scsi_device *sd = to_scsi_device(dev);
         struct device *class_dev;
-        int minor, ret = -ENOMEM;
+        int ret;
         scsi_changer *ch;
 
         if (sd->type != TYPE_MEDIUM_CHANGER)
@@ -905,22 +905,19 @@ static int ch_probe(struct device *dev)
         if (NULL == ch)
                 return -ENOMEM;
 
-        if (!idr_pre_get(&ch_index_idr, GFP_KERNEL))
-                goto free_ch;
-
+        idr_preload(GFP_KERNEL);
         spin_lock(&ch_index_lock);
-        ret = idr_get_new(&ch_index_idr, ch, &minor);
+        ret = idr_alloc(&ch_index_idr, ch, 0, CH_MAX_DEVS + 1, GFP_NOWAIT);
         spin_unlock(&ch_index_lock);
+        idr_preload_end();
 
-        if (ret)
+        if (ret < 0) {
+                if (ret == -ENOSPC)
+                        ret = -ENODEV;
                 goto free_ch;
-
-        if (minor > CH_MAX_DEVS) {
-                ret = -ENODEV;
-                goto remove_idr;
         }
 
-        ch->minor = minor;
+        ch->minor = ret;
         sprintf(ch->name,"ch%d",ch->minor);
 
         class_dev = device_create(ch_sysfs_class, dev,
@@ -944,7 +941,7 @@ static int ch_probe(struct device *dev)
 
         return 0;
 remove_idr:
-        idr_remove(&ch_index_idr, minor);
+        idr_remove(&ch_index_idr, ch->minor);
 free_ch:
         kfree(ch);
         return ret;
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index be2c9a6561ff..9f0c46547459 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -1391,24 +1391,23 @@ static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
                 return ERR_PTR(-ENOMEM);
         }
 
-        if (!idr_pre_get(&sg_index_idr, GFP_KERNEL)) {
-                printk(KERN_WARNING "idr expansion Sg_device failure\n");
-                error = -ENOMEM;
-                goto out;
-        }
-
+        idr_preload(GFP_KERNEL);
         write_lock_irqsave(&sg_index_lock, iflags);
 
-        error = idr_get_new(&sg_index_idr, sdp, &k);
-        if (error) {
-                write_unlock_irqrestore(&sg_index_lock, iflags);
-                printk(KERN_WARNING "idr allocation Sg_device failure: %d\n",
-                       error);
-                goto out;
+        error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);
+        if (error < 0) {
+                if (error == -ENOSPC) {
+                        sdev_printk(KERN_WARNING, scsidp,
+                                    "Unable to attach sg device type=%d, minor number exceeds %d\n",
+                                    scsidp->type, SG_MAX_DEVS - 1);
+                        error = -ENODEV;
+                } else {
+                        printk(KERN_WARNING
+                               "idr allocation Sg_device failure: %d\n", error);
+                }
+                goto out_unlock;
         }
-
-        if (unlikely(k >= SG_MAX_DEVS))
-                goto overflow;
+        k = error;
 
         SCSI_LOG_TIMEOUT(3, printk("sg_alloc: dev=%d \n", k));
         sprintf(disk->disk_name, "sg%d", k);
@@ -1420,25 +1419,17 @@ static Sg_device *sg_alloc(struct gendisk *disk, struct scsi_device *scsidp)
         sdp->sg_tablesize = queue_max_segments(q);
         sdp->index = k;
         kref_init(&sdp->d_ref);
+        error = 0;
 
+out_unlock:
         write_unlock_irqrestore(&sg_index_lock, iflags);
+        idr_preload_end();
 
-        error = 0;
- out:
         if (error) {
                 kfree(sdp);
                 return ERR_PTR(error);
         }
         return sdp;
-
- overflow:
-        idr_remove(&sg_index_idr, k);
-        write_unlock_irqrestore(&sg_index_lock, iflags);
-        sdev_printk(KERN_WARNING, scsidp,
-                    "Unable to attach sg device type=%d, minor "
-                    "number exceeds %d\n", scsidp->type, SG_MAX_DEVS - 1);
-        error = -ENODEV;
-        goto out;
 }
 
 static int
diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index 3e2b3717cb5c..86974471af68 100644
--- a/drivers/scsi/st.c
+++ b/drivers/scsi/st.c
@@ -4076,7 +4076,7 @@ static int st_probe(struct device *dev)
         struct st_modedef *STm;
         struct st_partstat *STps;
         struct st_buffer *buffer;
-        int i, dev_num, error;
+        int i, error;
         char *stp;
 
         if (SDp->type != TYPE_TAPE)
@@ -4178,27 +4178,17 @@ static int st_probe(struct device *dev)
             tpnt->blksize_changed = 0;
         mutex_init(&tpnt->lock);
 
-        if (!idr_pre_get(&st_index_idr, GFP_KERNEL)) {
-                pr_warn("st: idr expansion failed\n");
-                error = -ENOMEM;
-                goto out_put_disk;
-        }
-
+        idr_preload(GFP_KERNEL);
         spin_lock(&st_index_lock);
-        error = idr_get_new(&st_index_idr, tpnt, &dev_num);
+        error = idr_alloc(&st_index_idr, tpnt, 0, ST_MAX_TAPES + 1, GFP_NOWAIT);
         spin_unlock(&st_index_lock);
-        if (error) {
+        idr_preload_end();
+        if (error < 0) {
                 pr_warn("st: idr allocation failed: %d\n", error);
                 goto out_put_disk;
         }
-
-        if (dev_num > ST_MAX_TAPES) {
-                pr_err("st: Too many tape devices (max. %d).\n", ST_MAX_TAPES);
-                goto out_put_index;
-        }
-
-        tpnt->index = dev_num;
-        sprintf(disk->disk_name, "st%d", dev_num);
+        tpnt->index = error;
+        sprintf(disk->disk_name, "st%d", tpnt->index);
 
         dev_set_drvdata(dev, tpnt);
 
@@ -4218,9 +4208,8 @@ static int st_probe(struct device *dev)
 
 out_remove_devs:
         remove_cdevs(tpnt);
-out_put_index:
         spin_lock(&st_index_lock);
-        idr_remove(&st_index_idr, dev_num);
+        idr_remove(&st_index_idr, tpnt->index);
         spin_unlock(&st_index_lock);
 out_put_disk:
         put_disk(disk);