summaryrefslogtreecommitdiffstats
path: root/block
diff options
context:
space:
mode:
authorDenis V. Lunev <den@openvz.org>2015-01-30 11:42:14 +0300
committerKevin Wolf <kwolf@redhat.com>2015-02-06 17:24:20 +0100
commitb953f075007a7860adce9fa410b2e116a3d5e29c (patch)
treea74183d720dfb65c01b65fc9acd93c9939f11f2e /block
parent37cc9f7f684ed035da63274daca1594c7ee16213 (diff)
downloadhqemu-b953f075007a7860adce9fa410b2e116a3d5e29c.zip
hqemu-b953f075007a7860adce9fa410b2e116a3d5e29c.tar.gz
block: use fallocate(FALLOC_FL_ZERO_RANGE) in handle_aiocb_write_zeroes
This efficiently writes zeroes on Linux if the kernel is capable enough. FALLOC_FL_ZERO_RANGE correctly handles all cases, including and not including file expansion. CC: Kevin Wolf <kwolf@redhat.com> CC: Stefan Hajnoczi <stefanha@redhat.com> CC: Peter Lieven <pl@kamp.de> CC: Fam Zheng <famz@redhat.com> Signed-off-by: Denis V. Lunev <den@openvz.org> Reviewed-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'block')
-rw-r--r--block/raw-posix.c15
1 files changed, 13 insertions, 2 deletions
diff --git a/block/raw-posix.c b/block/raw-posix.c
index d3910fd..5a777e7 100644
--- a/block/raw-posix.c
+++ b/block/raw-posix.c
@@ -60,7 +60,7 @@
#define FS_NOCOW_FL 0x00800000 /* Do not cow file */
#endif
#endif
-#ifdef CONFIG_FALLOCATE_PUNCH_HOLE
+#if defined(CONFIG_FALLOCATE_PUNCH_HOLE) || defined(CONFIG_FALLOCATE_ZERO_RANGE)
#include <linux/falloc.h>
#endif
#if defined (__FreeBSD__) || defined(__FreeBSD_kernel__)
@@ -902,7 +902,7 @@ static int translate_err(int err)
return err;
}
-#if defined(CONFIG_FALLOCATE_PUNCH_HOLE)
+#if defined(CONFIG_FALLOCATE_PUNCH_HOLE) || defined(CONFIG_FALLOCATE_ZERO_RANGE)
static int do_fallocate(int fd, int mode, off_t offset, off_t len)
{
do {
@@ -954,6 +954,17 @@ static ssize_t handle_aiocb_write_zeroes(RawPosixAIOData *aiocb)
}
#endif
+#ifdef CONFIG_FALLOCATE_ZERO_RANGE
+ if (s->has_write_zeroes) {
+ int ret = do_fallocate(s->fd, FALLOC_FL_ZERO_RANGE,
+ aiocb->aio_offset, aiocb->aio_nbytes);
+ if (ret == 0 || ret != -ENOTSUP) {
+ return ret;
+ }
+ s->has_write_zeroes = false;
+ }
+#endif
+
return -ENOTSUP;
}
OpenPOWER on IntegriCloud