make a few block drivers highmem safe

make a few block drivers highmem safe

[Christoph Hellwig]

Hi all,

this series converts a few random block drivers to be highmem safe,
in preparation of eventually getting rid of the block layer bounce
buffering support.

[PATCH 1/7] mtip32xx: don't use block layer bounce buffers

[Christoph Hellwig]

mtip32xx just sets the block bounce limit to the dma mask, which means
that the iommu or swiotlb already take care of the bounce buffering,
and the block bouncing can be removed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/block/mtip32xx/mtip32xx.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index 769c551e3d71..b03bb27dcc58 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -3862,7 +3862,6 @@ static int mtip_block_initialize(struct driver_data *dd)
 	blk_queue_max_hw_sectors(dd->queue, 0xffff);
 	blk_queue_max_segment_size(dd->queue, 0x400000);
 	blk_queue_io_min(dd->queue, 4096);
-	blk_queue_bounce_limit(dd->queue, dd->pdev->dma_mask);
 
 	/* Signal trim support */
 	if (dd->trim_supp == true) {
-- 
2.17.0

Re: [PATCH 1/7] mtip32xx: don't use block layer bounce buffers

[Johannes Thumshirn]

Looks good,
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
-- 
Johannes Thumshirn                                          Storage
jthumshirn@suse.de                                +49 911 74053 689
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N�rnberg
GF: Felix Imend�rffer, Jane Smithard, Graham Norton
HRB 21284 (AG N�rnberg)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850

[PATCH 2/7] DAC960: don't use block layer bounce buffers

[Christoph Hellwig]

DAC960 just sets the block bounce limit to the dma mask, which means
that the iommu or swiotlb already take care of the bounce buffering,
and the block bouncing can be removed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/block/DAC960.c | 9 ++-------
 drivers/block/DAC960.h | 1 -
 2 files changed, 2 insertions(+), 8 deletions(-)

diff --git a/drivers/block/DAC960.c b/drivers/block/DAC960.c
index f781eff7d23e..c9ba48519d0f 100644
--- a/drivers/block/DAC960.c
+++ b/drivers/block/DAC960.c
@@ -1179,7 +1179,6 @@ static bool DAC960_V1_EnableMemoryMailboxInterface(DAC960_Controller_T
 
   if (pci_set_dma_mask(Controller->PCIDevice, DMA_BIT_MASK(32)))
 	return DAC960_Failure(Controller, "DMA mask out of range");
-  Controller->BounceBufferLimit = DMA_BIT_MASK(32);
 
   if ((hw_type == DAC960_PD_Controller) || (hw_type == DAC960_P_Controller)) {
     CommandMailboxesSize =  0;
@@ -1380,11 +1379,8 @@ static bool DAC960_V2_EnableMemoryMailboxInterface(DAC960_Controller_T
   dma_addr_t	CommandMailboxDMA;
   DAC960_V2_CommandStatus_T CommandStatus;
 
-	if (!pci_set_dma_mask(Controller->PCIDevice, DMA_BIT_MASK(64)))
-		Controller->BounceBufferLimit = DMA_BIT_MASK(64);
-	else if (!pci_set_dma_mask(Controller->PCIDevice, DMA_BIT_MASK(32)))
-		Controller->BounceBufferLimit = DMA_BIT_MASK(32);
-	else
+	if (pci_set_dma_mask(Controller->PCIDevice, DMA_BIT_MASK(64)) &&
+	    pci_set_dma_mask(Controller->PCIDevice, DMA_BIT_MASK(32)))
 		return DAC960_Failure(Controller, "DMA mask out of range");
 
   /* This is a temporary dma mapping, used only in the scope of this function */
@@ -2540,7 +2536,6 @@ static bool DAC960_RegisterBlockDevice(DAC960_Controller_T *Controller)
 		continue;
   	}
   	Controller->RequestQueue[n] = RequestQueue;
-  	blk_queue_bounce_limit(RequestQueue, Controller->BounceBufferLimit);
   	RequestQueue->queuedata = Controller;
 	blk_queue_max_segments(RequestQueue, Controller->DriverScatterGatherLimit);
 	blk_queue_max_hw_sectors(RequestQueue, Controller->MaxBlocksPerCommand);
diff --git a/drivers/block/DAC960.h b/drivers/block/DAC960.h
index 21aff470d268..1439e651928b 100644
--- a/drivers/block/DAC960.h
+++ b/drivers/block/DAC960.h
@@ -2295,7 +2295,6 @@ typedef struct DAC960_Controller
   unsigned short MaxBlocksPerCommand;
   unsigned short ControllerScatterGatherLimit;
   unsigned short DriverScatterGatherLimit;
-  u64		BounceBufferLimit;
   unsigned int CombinedStatusBufferLength;
   unsigned int InitialStatusLength;
   unsigned int CurrentStatusLength;
-- 
2.17.0

Re: [PATCH 2/7] DAC960: don't use block layer bounce buffers

[Johannes Thumshirn]

Looks good,
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
-- 
Johannes Thumshirn                                          Storage
jthumshirn@suse.de                                +49 911 74053 689
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N�rnberg
GF: Felix Imend�rffer, Jane Smithard, Graham Norton
HRB 21284 (AG N�rnberg)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850

[PATCH 3/7] memstick: don't call blk_queue_bounce_limit

[Christoph Hellwig]

All in-tree host drivers set up a proper dma mask and use the dma-mapping
helpers.  This means they will be able to deal with any address that we
are throwing at them.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/memstick/core/ms_block.c    | 5 -----
 drivers/memstick/core/mspro_block.c | 5 -----
 2 files changed, 10 deletions(-)

diff --git a/drivers/memstick/core/ms_block.c b/drivers/memstick/core/ms_block.c
index 57b13dfbd21e..b2d025f42d14 100644
--- a/drivers/memstick/core/ms_block.c
+++ b/drivers/memstick/core/ms_block.c
@@ -2096,12 +2096,8 @@ static int msb_init_disk(struct memstick_dev *card)
 	struct msb_data *msb = memstick_get_drvdata(card);
 	struct memstick_host *host = card->host;
 	int rc;
-	u64 limit = BLK_BOUNCE_HIGH;
 	unsigned long capacity;
 
-	if (host->dev.dma_mask && *(host->dev.dma_mask))
-		limit = *(host->dev.dma_mask);
-
 	mutex_lock(&msb_disk_lock);
 	msb->disk_id = idr_alloc(&msb_disk_idr, card, 0, 256, GFP_KERNEL);
 	mutex_unlock(&msb_disk_lock);
@@ -2123,7 +2119,6 @@ static int msb_init_disk(struct memstick_dev *card)
 
 	msb->queue->queuedata = card;
 
-	blk_queue_bounce_limit(msb->queue, limit);
 	blk_queue_max_hw_sectors(msb->queue, MS_BLOCK_MAX_PAGES);
 	blk_queue_max_segments(msb->queue, MS_BLOCK_MAX_SEGS);
 	blk_queue_max_segment_size(msb->queue,
diff --git a/drivers/memstick/core/mspro_block.c b/drivers/memstick/core/mspro_block.c
index 8897962781bb..a2fadc605750 100644
--- a/drivers/memstick/core/mspro_block.c
+++ b/drivers/memstick/core/mspro_block.c
@@ -1175,12 +1175,8 @@ static int mspro_block_init_disk(struct memstick_dev *card)
 	struct mspro_sys_info *sys_info = NULL;
 	struct mspro_sys_attr *s_attr = NULL;
 	int rc, disk_id;
-	u64 limit = BLK_BOUNCE_HIGH;
 	unsigned long capacity;
 
-	if (host->dev.dma_mask && *(host->dev.dma_mask))
-		limit = *(host->dev.dma_mask);
-
 	for (rc = 0; msb->attr_group.attrs[rc]; ++rc) {
 		s_attr = mspro_from_sysfs_attr(msb->attr_group.attrs[rc]);
 
@@ -1219,7 +1215,6 @@ static int mspro_block_init_disk(struct memstick_dev *card)
 
 	msb->queue->queuedata = card;
 
-	blk_queue_bounce_limit(msb->queue, limit);
 	blk_queue_max_hw_sectors(msb->queue, MSPRO_BLOCK_MAX_PAGES);
 	blk_queue_max_segments(msb->queue, MSPRO_BLOCK_MAX_SEGS);
 	blk_queue_max_segment_size(msb->queue,
-- 
2.17.0

[PATCH 4/7] mtd_blkdevs: handle highmem pages

[Christoph Hellwig]

Just kmap the single payload page before passing it on to the FTL.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/mtd/mtd_blkdevs.c | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/drivers/mtd/mtd_blkdevs.c b/drivers/mtd/mtd_blkdevs.c
index 16ae4ae8e8f9..29c0bfd74e8a 100644
--- a/drivers/mtd/mtd_blkdevs.c
+++ b/drivers/mtd/mtd_blkdevs.c
@@ -82,7 +82,6 @@ static blk_status_t do_blktrans_request(struct mtd_blktrans_ops *tr,
 
 	block = blk_rq_pos(req) << 9 >> tr->blkshift;
 	nsect = blk_rq_cur_bytes(req) >> tr->blkshift;
-	buf = bio_data(req->bio);
 
 	if (req_op(req) == REQ_OP_FLUSH) {
 		if (tr->flush(dev))
@@ -100,9 +99,14 @@ static blk_status_t do_blktrans_request(struct mtd_blktrans_ops *tr,
 			return BLK_STS_IOERR;
 		return BLK_STS_OK;
 	case REQ_OP_READ:
-		for (; nsect > 0; nsect--, block++, buf += tr->blksize)
-			if (tr->readsect(dev, block, buf))
+		buf = kmap(bio_page(req->bio)) + bio_offset(req->bio);
+		for (; nsect > 0; nsect--, block++, buf += tr->blksize) {
+			if (tr->readsect(dev, block, buf)) {
+				kunmap(bio_page(req->bio));
 				return BLK_STS_IOERR;
+			}
+		}
+		kunmap(bio_page(req->bio));
 		rq_flush_dcache_pages(req);
 		return BLK_STS_OK;
 	case REQ_OP_WRITE:
@@ -110,9 +114,14 @@ static blk_status_t do_blktrans_request(struct mtd_blktrans_ops *tr,
 			return BLK_STS_IOERR;
 
 		rq_flush_dcache_pages(req);
-		for (; nsect > 0; nsect--, block++, buf += tr->blksize)
-			if (tr->writesect(dev, block, buf))
+		buf = kmap(bio_page(req->bio)) + bio_offset(req->bio);
+		for (; nsect > 0; nsect--, block++, buf += tr->blksize) {
+			if (tr->writesect(dev, block, buf)) {
+				kunmap(bio_page(req->bio));
 				return BLK_STS_IOERR;
+			}
+		}
+		kunmap(bio_page(req->bio));
 		return BLK_STS_OK;
 	default:
 		return BLK_STS_IOERR;
@@ -418,7 +427,6 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new)
 	new->rq->queuedata = new;
 	blk_queue_logical_block_size(new->rq, tr->blksize);
 
-	blk_queue_bounce_limit(new->rq, BLK_BOUNCE_HIGH);
 	blk_queue_flag_set(QUEUE_FLAG_NONROT, new->rq);
 	blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, new->rq);
 
-- 
2.17.0

[PATCH 5/7] aoe: handle highmem pages

[Christoph Hellwig]

Use kmap_atomic when copying out of a bio_vec.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/block/aoe/aoeblk.c | 1 -
 drivers/block/aoe/aoecmd.c | 3 ++-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/block/aoe/aoeblk.c b/drivers/block/aoe/aoeblk.c
index 6797e6c23c8a..027b876370bc 100644
--- a/drivers/block/aoe/aoeblk.c
+++ b/drivers/block/aoe/aoeblk.c
@@ -388,7 +388,6 @@ aoeblk_gdalloc(void *vp)
 			d->aoemajor, d->aoeminor);
 		goto err_mempool;
 	}
-	blk_queue_bounce_limit(q, BLK_BOUNCE_HIGH);
 
 	spin_lock_irqsave(&d->lock, flags);
 	WARN_ON(!(d->flags & DEVFL_GD_NOW));
diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index 540bb60cd071..096882e54095 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -1032,8 +1032,9 @@ bvcpy(struct sk_buff *skb, struct bio *bio, struct bvec_iter iter, long cnt)
 	iter.bi_size = cnt;
 
 	__bio_for_each_segment(bv, bio, iter, iter) {
-		char *p = page_address(bv.bv_page) + bv.bv_offset;
+		char *p = kmap_atomic(bv.bv_page) + bv.bv_offset;
 		skb_copy_bits(skb, soff, p, bv.bv_len);
+		kunmap_atomic(p);
 		soff += bv.bv_len;
 	}
 }
-- 
2.17.0

[PATCH 6/7] jsflash: handle highmem pages

[Christoph Hellwig]

Just kmap the bio single page payload before processing it.

(and yes, now highmem on sparc32 anyway, but kmap_(un)map atomic are nops,
so this gives the right example)

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/sbus/char/jsflash.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/sbus/char/jsflash.c b/drivers/sbus/char/jsflash.c
index 14f377ac1280..8520587b8d09 100644
--- a/drivers/sbus/char/jsflash.c
+++ b/drivers/sbus/char/jsflash.c
@@ -215,6 +215,7 @@ static void jsfd_request(void)
 		unsigned long offset = blk_rq_pos(req) << 9;
 		size_t len = blk_rq_cur_bytes(req);
 		blk_status_t err = BLK_STS_IOERR;
+		void *p;
 
 		if ((offset + len) > jdp->dsize)
 			goto end;
@@ -229,7 +230,9 @@ static void jsfd_request(void)
 			goto end;
 		}
 
-		jsfd_read(bio_data(req->bio), jdp->dbase + offset, len);
+		p = kmap_atomic(bio_page(bio)) + bio_offset(bio);
+		jsfd_read(p, jdp->dbase + offset, len);
+		kunmap_atomic(p);
 		err = BLK_STS_OK;
 	end:
 		if (!__blk_end_request_cur(req, err))
@@ -592,7 +595,6 @@ static int jsfd_init(void)
 			put_disk(disk);
 			goto out;
 		}
-		blk_queue_bounce_limit(disk->queue, BLK_BOUNCE_HIGH);
 		jsfd_disk[i] = disk;
 	}
 
-- 
2.17.0

[PATCH 7/7] ps3disk: handle highmem pages

[Christoph Hellwig]

The ps3disk driver already kmaps all pages when copying from/to the
internal bounce buffer, so it can accept highmem pages just fine.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/block/ps3disk.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/block/ps3disk.c b/drivers/block/ps3disk.c
index 075662f2cf46..afe1508d82c6 100644
--- a/drivers/block/ps3disk.c
+++ b/drivers/block/ps3disk.c
@@ -465,8 +465,6 @@ static int ps3disk_probe(struct ps3_system_bus_device *_dev)
 	priv->queue = queue;
 	queue->queuedata = dev;
 
-	blk_queue_bounce_limit(queue, BLK_BOUNCE_HIGH);
-
 	blk_queue_max_hw_sectors(queue, dev->bounce_size >> 9);
 	blk_queue_segment_boundary(queue, -1UL);
 	blk_queue_dma_alignment(queue, dev->blk_size-1);
-- 
2.17.0

Re: make a few block drivers highmem safe

[Jens Axboe]

On 5/9/18 7:59 AM, Christoph Hellwig wrote:
> Hi all,
> 
> this series converts a few random block drivers to be highmem safe,
> in preparation of eventually getting rid of the block layer bounce
> buffering support.

Series looks good to me.

-- 
Jens Axboe

Re: make a few block drivers highmem safe

[Jens Axboe]

On 5/9/18 7:59 AM, Christoph Hellwig wrote:
> Hi all,
> 
> this series converts a few random block drivers to be highmem safe,
> in preparation of eventually getting rid of the block layer bounce
> buffering support.

Applied, thanks.

-- 
Jens Axboe