diff mbox

btrfs-progs: make device discard process interruptible

Message ID 1395933577-32330-1-git-send-email-dsterba@suse.cz (mailing list archive)
State Accepted, archived
Headers show

Commit Message

David Sterba March 27, 2014, 3:19 p.m. UTC 
The ioctl for the whole range is not interruptible, which can be
annoying when the discard is not wanted but user forgets to use the -K
option.

Signed-off-by: David Sterba <dsterba@suse.cz>
---
 utils.c | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)
diff mbox

Patch

diff --git a/utils.c b/utils.c
index 013d74f9a0cd..3e9c527a492c 100644
--- a/utils.c
+++ b/utils.c
@@ -52,8 +52,10 @@ 
 #define BLKDISCARD	_IO(0x12,119)
 #endif
 
-static int
-discard_blocks(int fd, u64 start, u64 len)
+/*
+ * Discard the given range in one go
+ */
+static int discard_range(int fd, u64 start, u64 len)
 {
 	u64 range[2] = { start, len };
 
@@ -62,6 +64,26 @@  discard_blocks(int fd, u64 start, u64 len)
 	return 0;
 }
 
+/*
+ * Discard blocks in the given range in 1G chunks, the process is interruptible
+ */
+static int discard_blocks(int fd, u64 start, u64 len)
+{
+	while (len > 0) {
+		/* 1G granularity */
+		u64 chunk_size = min_t(u64, len, 1*1024*1024*1024);
+		int ret;
+
+		ret = discard_range(fd, start, chunk_size);
+		if (ret)
+			return ret;
+		len -= chunk_size;
+		start += chunk_size;
+	}
+
+	return 0;
+}
+
 static u64 reference_root_table[] = {
 	[1] =	BTRFS_ROOT_TREE_OBJECTID,
 	[2] =	BTRFS_EXTENT_TREE_OBJECTID,