On 2/23/2019 10:51 AM, Gustavo A. R. Silva wrote:
Update the code to use a zero-sized array instead of a pointer in structure nvmet_fc_tgt_queue and use struct_size() in kzalloc().Notice that one of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct foo { int stuff; struct boo entry[]; }; instance = kzalloc(sizeof(struct foo) + sizeof(struct boo) * count, GFP_KERNEL); Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <[email protected]> --- drivers/nvme/target/fc.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/drivers/nvme/target/fc.c b/drivers/nvme/target/fc.c index 1e9654f04c60..23baec38f97e 100644 --- a/drivers/nvme/target/fc.c +++ b/drivers/nvme/target/fc.c @@ -128,12 +128,12 @@ struct nvmet_fc_tgt_queue { struct nvmet_cq nvme_cq; struct nvmet_sq nvme_sq; struct nvmet_fc_tgt_assoc *assoc; - struct nvmet_fc_fcp_iod *fod; /* array of fcp_iods */ struct list_head fod_list; struct list_head pending_cmd_list; struct list_head avail_defer_list; struct workqueue_struct *work_q; struct kref ref; + struct nvmet_fc_fcp_iod fod[]; /* array of fcp_iods */ } __aligned(sizeof(unsigned long long));struct nvmet_fc_tgt_assoc {@@ -588,9 +588,7 @@ nvmet_fc_alloc_target_queue(struct nvmet_fc_tgt_assoc *assoc, if (qid > NVMET_NR_QUEUES) return NULL;- queue = kzalloc((sizeof(*queue) +- (sizeof(struct nvmet_fc_fcp_iod) * sqsize)), - GFP_KERNEL); + queue = kzalloc(struct_size(queue, fod, sqsize), GFP_KERNEL); if (!queue) return NULL;@@ -603,7 +601,6 @@ nvmet_fc_alloc_target_queue(struct nvmet_fc_tgt_assoc *assoc,if (!queue->work_q) goto out_a_put;- queue->fod = (struct nvmet_fc_fcp_iod *)&queue[1];queue->qid = qid; queue->sqsize = sqsize; queue->assoc = assoc;
Reviewed-by: James Smart <[email protected]> I guess this is a better style. -- james
