[PATCH] scsi: bnx2fc: Use a flexible array at the end of struct bnx2fc_cmd_mgr

[Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>]

The 'cmds' field in "struct bnx2fc_cmd_mgr" can be turned into a flexible
array.

This:
   - makes the code more readable and safer because struct_size() can now
     be used
   - saves the size of a pointer when allocating struct bnx2fc_cmd_mgr in
     bnx2fc_cmd_mgr_alloc()
   - avoid some pointer arithmetic when computing "cmgr->cmds"
   - saves an indirection when using the 'cmds array

Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
---
Compile tested only
---
 drivers/scsi/bnx2fc/bnx2fc.h    | 2 +-
 drivers/scsi/bnx2fc/bnx2fc_io.c | 7 +------
 2 files changed, 2 insertions(+), 7 deletions(-)

diff --git a/drivers/scsi/bnx2fc/bnx2fc.h b/drivers/scsi/bnx2fc/bnx2fc.h
index 7e74f77da14f..dfe7e0e8fdbd 100644
--- a/drivers/scsi/bnx2fc/bnx2fc.h
+++ b/drivers/scsi/bnx2fc/bnx2fc.h
@@ -281,7 +281,7 @@ struct bnx2fc_cmd_mgr {
 	struct list_head *free_list;
 	spinlock_t *free_list_lock;
 	struct io_bdt **io_bdt_pool;
-	struct bnx2fc_cmd **cmds;
+	struct bnx2fc_cmd *cmds[];
 };
 
 struct bnx2fc_rport {
diff --git a/drivers/scsi/bnx2fc/bnx2fc_io.c b/drivers/scsi/bnx2fc/bnx2fc_io.c
index 33057908f147..8e381081e487 100644
--- a/drivers/scsi/bnx2fc/bnx2fc_io.c
+++ b/drivers/scsi/bnx2fc/bnx2fc_io.c
@@ -213,7 +213,6 @@ struct bnx2fc_cmd_mgr *bnx2fc_cmd_mgr_alloc(struct bnx2fc_hba *hba)
 	struct bnx2fc_cmd_mgr *cmgr;
 	struct io_bdt *bdt_info;
 	struct bnx2fc_cmd *io_req;
-	size_t len;
 	u32 mem_size;
 	u16 xid;
 	int i;
@@ -231,10 +230,8 @@ struct bnx2fc_cmd_mgr *bnx2fc_cmd_mgr_alloc(struct bnx2fc_hba *hba)
 	BNX2FC_MISC_DBG("min xid 0x%x, max xid 0x%x\n", min_xid, max_xid);
 
 	num_ios = max_xid - min_xid + 1;
-	len = (num_ios * (sizeof(struct bnx2fc_cmd *)));
-	len += sizeof(struct bnx2fc_cmd_mgr);
 
-	cmgr = kzalloc(len, GFP_KERNEL);
+	cmgr = kzalloc(struct_size(cmgr, cmds, num_ios), GFP_KERNEL);
 	if (!cmgr) {
 		printk(KERN_ERR PFX "failed to alloc cmgr\n");
 		return NULL;
@@ -257,8 +254,6 @@ struct bnx2fc_cmd_mgr *bnx2fc_cmd_mgr_alloc(struct bnx2fc_hba *hba)
 		goto mem_err;
 	}
 
-	cmgr->cmds = (struct bnx2fc_cmd **)(cmgr + 1);
-
 	for (i = 0; i < arr_sz; i++)  {
 		INIT_LIST_HEAD(&cmgr->free_list[i]);
 		spin_lock_init(&cmgr->free_list_lock[i]);
-- 
2.45.1