[SCSI] scsi_host_lookup: error returns and NULL pointers
This patch cleans up the behavior of scsi_host_lookup().
The original implementation attempted to use the dual role of
either returning a pointer value, or a negative error code.
User's needed to use IS_ERR() to check the result. Additionally,
the IS_ERR() macro never checks for when a NULL pointer was
returned, so a NULL pointer actually passes with a success case.
Note: scsi_host_get(), used by scsi_host_lookup(), can return
a NULL pointer.
Talk about a mudhole for the unitiated to step into....
This patch converts scsi_host_lookup() to return either NULL
or a valid pointer. The consumers were updated for the change.
Signed-off-by: James Smart <james.smart@emulex.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/scsi_tgt_lib.c b/drivers/scsi/scsi_tgt_lib.c
index 257e097..f26299d 100644
--- a/drivers/scsi/scsi_tgt_lib.c
+++ b/drivers/scsi/scsi_tgt_lib.c
@@ -460,7 +460,7 @@
/* TODO: replace with a O(1) alg */
shost = scsi_host_lookup(host_no);
- if (IS_ERR(shost)) {
+ if (!shost) {
printk(KERN_ERR "Could not find host no %d\n", host_no);
return -EINVAL;
}
@@ -550,7 +550,7 @@
dprintk("%d %d %llx\n", host_no, result, (unsigned long long) mid);
shost = scsi_host_lookup(host_no);
- if (IS_ERR(shost)) {
+ if (!shost) {
printk(KERN_ERR "Could not find host no %d\n", host_no);
return err;
}
@@ -603,7 +603,7 @@
dprintk("%d %d%llx\n", host_no, result, (unsigned long long)itn_id);
shost = scsi_host_lookup(host_no);
- if (IS_ERR(shost)) {
+ if (!shost) {
printk(KERN_ERR "Could not find host no %d\n", host_no);
return err;
}