[PATCH] btrfs: Fix -Wunused-but-set-variable warnings

From: Andrey Abramov
Date: Fri May 31 2019 - 16:04:20 EST


Fix -Wunused-but-set-variable warnings in raid56.c and sysfs.c files

Signed-off-by: Andrey Abramov <st5pub@xxxxxxxxx>
---
fs/btrfs/raid56.c | 32 +++++++++++---------------------
fs/btrfs/sysfs.c | 5 +----
2 files changed, 12 insertions(+), 25 deletions(-)

diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c
index f3d0576dd327..4ab29eacfdf3 100644
--- a/fs/btrfs/raid56.c
+++ b/fs/btrfs/raid56.c
@@ -1182,22 +1182,17 @@ static noinline void finish_rmw(struct btrfs_raid_bio *rbio)
int nr_data = rbio->nr_data;
int stripe;
int pagenr;
- int p_stripe = -1;
- int q_stripe = -1;
+ int is_q_stripe = 0;
struct bio_list bio_list;
struct bio *bio;
int ret;

bio_list_init(&bio_list);

- if (rbio->real_stripes - rbio->nr_data == 1) {
- p_stripe = rbio->real_stripes - 1;
- } else if (rbio->real_stripes - rbio->nr_data == 2) {
- p_stripe = rbio->real_stripes - 2;
- q_stripe = rbio->real_stripes - 1;
- } else {
+ if (rbio->real_stripes - rbio->nr_data == 2)
+ is_q_stripe = 1;
+ else if (rbio->real_stripes - rbio->nr_data != 1)
BUG();
- }

/* at this point we either have a full stripe,
* or we've read the full stripe from the drive.
@@ -1241,7 +1236,7 @@ static noinline void finish_rmw(struct btrfs_raid_bio *rbio)
SetPageUptodate(p);
pointers[stripe++] = kmap(p);

- if (q_stripe != -1) {
+ if (is_q_stripe) {

/*
* raid6, add the qstripe and call the
@@ -2340,8 +2335,7 @@ static noinline void finish_parity_scrub(struct btrfs_raid_bio *rbio,
int nr_data = rbio->nr_data;
int stripe;
int pagenr;
- int p_stripe = -1;
- int q_stripe = -1;
+ int is_q_stripe = 0;
struct page *p_page = NULL;
struct page *q_page = NULL;
struct bio_list bio_list;
@@ -2351,14 +2345,10 @@ static noinline void finish_parity_scrub(struct btrfs_raid_bio *rbio,

bio_list_init(&bio_list);

- if (rbio->real_stripes - rbio->nr_data == 1) {
- p_stripe = rbio->real_stripes - 1;
- } else if (rbio->real_stripes - rbio->nr_data == 2) {
- p_stripe = rbio->real_stripes - 2;
- q_stripe = rbio->real_stripes - 1;
- } else {
+ if (rbio->real_stripes - rbio->nr_data == 2)
+ is_q_stripe = 1;
+ else if (rbio->real_stripes - rbio->nr_data != 1)
BUG();
- }

if (bbio->num_tgtdevs && bbio->tgtdev_map[rbio->scrubp]) {
is_replace = 1;
@@ -2380,7 +2370,7 @@ static noinline void finish_parity_scrub(struct btrfs_raid_bio *rbio,
goto cleanup;
SetPageUptodate(p_page);

- if (q_stripe != -1) {
+ if (is_q_stripe) {
q_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM);
if (!q_page) {
__free_page(p_page);
@@ -2403,7 +2393,7 @@ static noinline void finish_parity_scrub(struct btrfs_raid_bio *rbio,
/* then add the parity stripe */
pointers[stripe++] = kmap(p_page);

- if (q_stripe != -1) {
+ if (is_q_stripe) {

/*
* raid6, add the qstripe and call the
diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index 2f078b77fe14..514b75dec4a9 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -887,13 +887,10 @@ void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
{
struct btrfs_fs_devices *fs_devs;
struct kobject *fsid_kobj;
- u64 features;
- int ret;

if (!fs_info)
return;

- features = get_features(fs_info, set);
ASSERT(bit & supported_feature_masks[set]);

fs_devs = fs_info->fs_devices;
@@ -907,7 +904,7 @@ void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
* to use sysfs_update_group but some refactoring is needed first.
*/
sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
- ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);
+ sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);
}

static int btrfs_init_debugfs(void)
--
2.20.1