Merge remote-tracking branch 'torvalds/master' into perf/core

To get closer to upstream and check if we need to sync more UAPI
headers, pick up fixes for libbpf that prevent perf's container tests
from completing successfuly, etc.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 73 insertions, 40 deletions

diff --git a/fs/block_dev.c b/fs/block_dev.c
index c2a85b587922..eb657ab94060 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -349,7 +349,7 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
 	loff_t pos = iocb->ki_pos;
 	blk_qc_t qc = BLK_QC_T_NONE;
 	gfp_t gfp;
-	ssize_t ret;
+	int ret;
 
 	if ((pos | iov_iter_alignment(iter)) &
 	    (bdev_logical_block_size(bdev) - 1))
@@ -386,8 +386,6 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
 
 	ret = 0;
 	for (;;) {
-		int err;
-
 		bio_set_dev(bio, bdev);
 		bio->bi_iter.bi_sector = pos >> 9;
 		bio->bi_write_hint = iocb->ki_hint;
@@ -395,10 +393,8 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
 		bio->bi_end_io = blkdev_bio_end_io;
 		bio->bi_ioprio = iocb->ki_ioprio;
 
-		err = bio_iov_iter_get_pages(bio, iter);
-		if (unlikely(err)) {
-			if (!ret)
-				ret = err;
+		ret = bio_iov_iter_get_pages(bio, iter);
+		if (unlikely(ret)) {
 			bio->bi_status = BLK_STS_IOERR;
 			bio_endio(bio);
 			break;
@@ -421,7 +417,6 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
 		if (nowait)
 			bio->bi_opf |= (REQ_NOWAIT | REQ_NOWAIT_INLINE);
 
-		dio->size += bio->bi_iter.bi_size;
 		pos += bio->bi_iter.bi_size;
 
 		nr_pages = iov_iter_npages(iter, BIO_MAX_PAGES);
@@ -433,10 +428,11 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
 				polled = true;
 			}
 
+			dio->size += bio->bi_iter.bi_size;
 			qc = submit_bio(bio);
 			if (qc == BLK_QC_T_EAGAIN) {
-				if (!ret)
-					ret = -EAGAIN;
+				dio->size -= bio->bi_iter.bi_size;
+				ret = -EAGAIN;
 				goto error;
 			}
 
@@ -459,18 +455,17 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
 			atomic_inc(&dio->ref);
 		}
 
+		dio->size += bio->bi_iter.bi_size;
 		qc = submit_bio(bio);
 		if (qc == BLK_QC_T_EAGAIN) {
-			if (!ret)
-				ret = -EAGAIN;
+			dio->size -= bio->bi_iter.bi_size;
+			ret = -EAGAIN;
 			goto error;
 		}
-		ret += bio->bi_iter.bi_size;
 
 		bio = bio_alloc(gfp, nr_pages);
 		if (!bio) {
-			if (!ret)
-				ret = -EAGAIN;
+			ret = -EAGAIN;
 			goto error;
 		}
 	}
@@ -495,6 +490,8 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
 out:
 	if (!ret)
 		ret = blk_status_to_errno(dio->bio.bi_status);
+	if (likely(!ret))
+		ret = dio->size;
 
 	bio_put(&dio->bio);
 	return ret;
@@ -1181,8 +1178,7 @@ static struct gendisk *bdev_get_gendisk(struct block_device *bdev, int *partno)
  * Pointer to the block device containing @bdev on success, ERR_PTR()
  * value on failure.
  */
-static struct block_device *bd_start_claiming(struct block_device *bdev,
-					      void *holder)
+struct block_device *bd_start_claiming(struct block_device *bdev, void *holder)
 {
 	struct gendisk *disk;
 	struct block_device *whole;
@@ -1229,6 +1225,62 @@ static struct block_device *bd_start_claiming(struct block_device *bdev,
 		return ERR_PTR(err);
 	}
 }
+EXPORT_SYMBOL(bd_start_claiming);
+
+static void bd_clear_claiming(struct block_device *whole, void *holder)
+{
+	lockdep_assert_held(&bdev_lock);
+	/* tell others that we're done */
+	BUG_ON(whole->bd_claiming != holder);
+	whole->bd_claiming = NULL;
+	wake_up_bit(&whole->bd_claiming, 0);
+}
+
+/**
+ * bd_finish_claiming - finish claiming of a block device
+ * @bdev: block device of interest
+ * @whole: whole block device (returned from bd_start_claiming())
+ * @holder: holder that has claimed @bdev
+ *
+ * Finish exclusive open of a block device. Mark the device as exlusively
+ * open by the holder and wake up all waiters for exclusive open to finish.
+ */
+void bd_finish_claiming(struct block_device *bdev, struct block_device *whole,
+			void *holder)
+{
+	spin_lock(&bdev_lock);
+	BUG_ON(!bd_may_claim(bdev, whole, holder));
+	/*
+	 * Note that for a whole device bd_holders will be incremented twice,
+	 * and bd_holder will be set to bd_may_claim before being set to holder
+	 */
+	whole->bd_holders++;
+	whole->bd_holder = bd_may_claim;
+	bdev->bd_holders++;
+	bdev->bd_holder = holder;
+	bd_clear_claiming(whole, holder);
+	spin_unlock(&bdev_lock);
+}
+EXPORT_SYMBOL(bd_finish_claiming);
+
+/**
+ * bd_abort_claiming - abort claiming of a block device
+ * @bdev: block device of interest
+ * @whole: whole block device (returned from bd_start_claiming())
+ * @holder: holder that has claimed @bdev
+ *
+ * Abort claiming of a block device when the exclusive open failed. This can be
+ * also used when exclusive open is not actually desired and we just needed
+ * to block other exclusive openers for a while.
+ */
+void bd_abort_claiming(struct block_device *bdev, struct block_device *whole,
+		       void *holder)
+{
+	spin_lock(&bdev_lock);
+	bd_clear_claiming(whole, holder);
+	spin_unlock(&bdev_lock);
+}
+EXPORT_SYMBOL(bd_abort_claiming);
 
 #ifdef CONFIG_SYSFS
 struct bd_holder_disk {
@@ -1698,29 +1750,10 @@ int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder)
 
 		/* finish claiming */
 		mutex_lock(&bdev->bd_mutex);
-		spin_lock(&bdev_lock);
-
-		if (!res) {
-			BUG_ON(!bd_may_claim(bdev, whole, holder));
-			/*
-			 * Note that for a whole device bd_holders
-			 * will be incremented twice, and bd_holder
-			 * will be set to bd_may_claim before being
-			 * set to holder
-			 */
-			whole->bd_holders++;
-			whole->bd_holder = bd_may_claim;
-			bdev->bd_holders++;
-			bdev->bd_holder = holder;
-		}
-
-		/* tell others that we're done */
-		BUG_ON(whole->bd_claiming != holder);
-		whole->bd_claiming = NULL;
-		wake_up_bit(&whole->bd_claiming, 0);
-
-		spin_unlock(&bdev_lock);
-
+		if (!res)
+			bd_finish_claiming(bdev, whole, holder);
+		else
+			bd_abort_claiming(bdev, whole, holder);
 		/*
 		 * Block event polling for write claims if requested.  Any
 		 * write holder makes the write_holder state stick until