s390/scm_block: allocate aidaw pages only when necessary (de88d0d2) · Commits · 戴 / test

drivers/s390/block/scm_blk.c

+28 −4

Original line number	Diff line number	Diff line
		@@ -121,7 +121,8 @@ static void scm_request_done(struct scm_request *scmrq)
		u64 aidaw = msb->data_addr;
		unsigned long flags;

		if ((msb->flags & MSB_FLAG_IDA) && aidaw)
		if ((msb->flags & MSB_FLAG_IDA) && aidaw &&
		IS_ALIGNED(aidaw, PAGE_SIZE))
		mempool_free(virt_to_page(aidaw), aidaw_pool);

		spin_lock_irqsave(&list_lock, flags);
		@@ -134,26 +135,47 @@ static bool scm_permit_request(struct scm_blk_dev bdev, struct request req)
		return rq_data_dir(req) != WRITE \|\| bdev->state != SCM_WR_PROHIBIT;
		}

		struct aidaw *scm_aidaw_alloc(void)
		static inline struct aidaw *scm_aidaw_alloc(void)
		{
		struct page *page = mempool_alloc(aidaw_pool, GFP_ATOMIC);

		return page ? page_address(page) : NULL;
		}

		static inline unsigned long scm_aidaw_bytes(struct aidaw *aidaw)
		{
		unsigned long _aidaw = (unsigned long) aidaw;
		unsigned long bytes = ALIGN(_aidaw, PAGE_SIZE) - _aidaw;

		return (bytes / sizeof(aidaw)) PAGE_SIZE;
		}

		struct aidaw scm_aidaw_fetch(struct scm_request scmrq, unsigned int bytes)
		{
		struct aidaw *aidaw;

		if (scm_aidaw_bytes(scmrq->next_aidaw) >= bytes)
		return scmrq->next_aidaw;

		aidaw = scm_aidaw_alloc();
		if (aidaw)
		memset(aidaw, 0, PAGE_SIZE);
		return aidaw;
		}

		static int scm_request_prepare(struct scm_request *scmrq)
		{
		struct scm_blk_dev *bdev = scmrq->bdev;
		struct scm_device *scmdev = bdev->gendisk->private_data;
		struct aidaw *aidaw = scm_aidaw_alloc();
		struct msb *msb = &scmrq->aob->msb[0];
		struct req_iterator iter;
		struct aidaw *aidaw;
		struct bio_vec bv;

		aidaw = scm_aidaw_fetch(scmrq, blk_rq_bytes(scmrq->request));
		if (!aidaw)
		return -ENOMEM;

		memset(aidaw, 0, PAGE_SIZE);
		msb->bs = MSB_BS_4K;
		scmrq->aob->request.msb_count = 1;
		msb->scm_addr = scmdev->address +
		@@ -188,6 +210,8 @@ static inline void scm_request_init(struct scm_blk_dev *bdev,
		scmrq->bdev = bdev;
		scmrq->retries = 4;
		scmrq->error = 0;
		/* We don't use all msbs - place aidaws at the end of the aob page. */
		scmrq->next_aidaw = (void *) &aob->msb[1];
		scm_request_cluster_init(scmrq);
		}

drivers/s390/block/scm_blk.h

+2 −1

Original line number	Diff line number	Diff line
		@@ -30,6 +30,7 @@ struct scm_blk_dev {

		struct scm_request {
		struct scm_blk_dev *bdev;
		struct aidaw *next_aidaw;
		struct request *request;
		struct aob *aob;
		struct list_head list;
		@@ -54,7 +55,7 @@ void scm_blk_irq(struct scm_device , void , int);
		void scm_request_finish(struct scm_request *);
		void scm_request_requeue(struct scm_request *);

		struct aidaw *scm_aidaw_alloc(void);
		struct aidaw scm_aidaw_fetch(struct scm_request scmrq, unsigned int bytes);

		int scm_drv_init(void);
		void scm_drv_cleanup(void);

drivers/s390/block/scm_blk_cluster.c

+6 −7

Original line number	Diff line number	Diff line
		@@ -131,16 +131,9 @@ static int scm_prepare_cluster_request(struct scm_request *scmrq)
		scmrq->cluster.state = CLUSTER_READ;
		/* fall through */
		case CLUSTER_READ:
		aidaw = scm_aidaw_alloc();
		if (!aidaw)
		return -ENOMEM;

		memset(aidaw, 0, PAGE_SIZE);
		scmrq->aob->request.msb_count = 1;
		msb->bs = MSB_BS_4K;
		msb->oc = MSB_OC_READ;
		msb->flags = MSB_FLAG_IDA;
		msb->data_addr = (u64) aidaw;
		msb->blk_count = write_cluster_size;

		addr = scmdev->address + ((u64) blk_rq_pos(req) << 9);
		@@ -151,6 +144,12 @@ static int scm_prepare_cluster_request(struct scm_request *scmrq)
		CLUSTER_SIZE))
		msb->blk_count = 2 * write_cluster_size;

		aidaw = scm_aidaw_fetch(scmrq, msb->blk_count * PAGE_SIZE);
		if (!aidaw)
		return -ENOMEM;

		scmrq->aob->request.msb_count = 1;
		msb->data_addr = (u64) aidaw;
		for (i = 0; i < msb->blk_count; i++) {
		aidaw->data_addr = (u64) scmrq->cluster.buf[i];
		aidaw++;

Admin message