From 2ef122da35899591737adca296b499246b877532 Mon Sep 17 00:00:00 2001 From: Andrei Vagin Date: Thu, 8 Nov 2018 17:38:50 -0800 Subject: Implement sync_file_range() sync_file_range - sync a file segment with disk In Linux, sync_file_range() accepts three flags: SYNC_FILE_RANGE_WAIT_BEFORE Wait upon write-out of all pages in the specified range that have already been submitted to the device driver for write-out before performing any write. SYNC_FILE_RANGE_WRITE Initiate write-out of all dirty pages in the specified range which are not presently submitted write-out. Note that even this may block if you attempt to write more than request queue size. SYNC_FILE_RANGE_WAIT_AFTER Wait upon write-out of all pages in the range after performing any write. In this implementation: SYNC_FILE_RANGE_WAIT_BEFORE without SYNC_FILE_RANGE_WAIT_AFTER isn't supported right now. SYNC_FILE_RANGE_WRITE is skipped. It should initiate write-out of all dirty pages, but it doesn't wait, so it should be safe to do nothing while nobody uses SYNC_FILE_RANGE_WAIT_BEFORE. SYNC_FILE_RANGE_WAIT_AFTER is equal to fdatasync(). In Linux, sync_file_range() doesn't writes out the file's meta-data, but fdatasync() does if a file size is changed. PiperOrigin-RevId: 220730840 Change-Id: Iae5dfb23c2c916967d67cf1a1ad32f25eb3f6286 --- pkg/abi/linux/fs.go | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'pkg/abi/linux') diff --git a/pkg/abi/linux/fs.go b/pkg/abi/linux/fs.go index 7817bfb52..0b1c9f3db 100644 --- a/pkg/abi/linux/fs.go +++ b/pkg/abi/linux/fs.go @@ -73,3 +73,10 @@ type Statfs struct { // Spare is unused. Spare [4]uint64 } + +// Sync_file_range flags, from include/uapi/linux/fs.h +const ( + SYNC_FILE_RANGE_WAIT_BEFORE = 1 + SYNC_FILE_RANGE_WRITE = 2 + SYNC_FILE_RANGE_WAIT_AFTER = 4 +) -- cgit v1.2.3