From: Zhang Yi <yi.zhang@xxxxxxxxxx> Add support for FALLOC_FL_WRITE_ZEROES. It directly calls blkdev_issue_zeroout() with flags set to 0. The underlying process will attempt to use the fastest method for issuing zeroes. First, the block layer will try to issue a write zeroes command if the storage device supports it; if not, it will fall back to issuing zeroed data. Then, the storage device driver may attempt to submit an unmap write zero command if the device supports it; if not, the driver may fall back to submitting a no-unmap write zeroes command. Signed-off-by: Zhang Yi <yi.zhang@xxxxxxxxxx> --- block/fops.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/block/fops.c b/block/fops.c index 77a5465309e7..e590c8997689 100644 --- a/block/fops.c +++ b/block/fops.c @@ -803,7 +803,7 @@ static ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to) #define BLKDEV_FALLOC_FL_SUPPORTED \ (FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | \ - FALLOC_FL_ZERO_RANGE) + FALLOC_FL_ZERO_RANGE | FALLOC_FL_WRITE_ZEROES) static long blkdev_fallocate(struct file *file, int mode, loff_t start, loff_t len) @@ -847,6 +847,9 @@ static long blkdev_fallocate(struct file *file, int mode, loff_t start, case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE: flags = BLKDEV_ZERO_NOFALLBACK; break; + case FALLOC_FL_WRITE_ZEROES: + flags = 0; + break; default: error = -EOPNOTSUPP; goto fail; -- 2.46.1
