Btrfs: improve the BIO_RW_DISCARD conditional compile func definition
PATCH 1/1 Btrfs: improve the BIO_RW_DISCARD conditional compile func definition
The conditional compile func definition shall better not be defined this way:
static int btrfs_issue_discard()
{
#ifdef BIO_RW_DISCARD ... #else return 0;
#endif
}
instead, can be better done this way:
#ifndef BIO_RW_DISCARD
static int btrfs_issue_discard()
{
return 0;
}#endif
#ifdef BIO_RW_DISCARD
static int btrfs_issue_discard()
{
...
}#endif
From 7647c248249905629b9254221d9cd00c9c6004e3 Mon Sep 17 00:00:00 2001
From: Jeffrey Wu <[email protected]>
Date: Sun, 30 Aug 2009 10:43:56 +0800
Subject: [PATCH] Btrfs: improved the BIO_RW_DISCARD function definition
Signed-off-by Jeffrey Wu <[email protected]>
--- fs/btrfs/extent-tree.c | 20 +++++++++++++++----- 1 files changed, 15 insertions(+), 5 deletions(-)
fs/btrfs/extent-tree.c +15 -5
@@ -62,6 +62,20 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans, struct btrfs_root *extent_root, u64 alloc_bytes, u64 flags, int force); +#ifndef BIO_RW_DISCARD +static void btrfs_issue_discard (struct block_device *bdev, +u64 start,u64 len) +{ +return ; +} + +static int btrfs_discard_extent (struct btrfs_root *root,u64 bytenr, +u64 num_bytes) +{ +return 0 ; +} +#endif + static noinline intblock_group_cache_done (struct btrfs_block_group_cache *cache) {
@@ -1513,12 +1527,10 @@ static void btrfs_issue_discard(struct block_device *bdev, {blkdev_issue_discard (bdev, start >>9 , len >>9 ,GFP_KERNEL ); } -#endif static int btrfs_discard_extent (struct btrfs_root *root,u64 bytenr,u64 num_bytes) { -#ifdef BIO_RW_DISCARD int ret;u64 map_length = num_bytes;struct btrfs_multi_bio *multi =NULL ;
@@ -1542,10 +1554,8 @@ static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr, }return ret; -#else -return 0 ; -#endif } +#endif int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
Signature · 1 line
1.6.0.4