[PATCH v2] staging: exfat: remove 'vol_type' variable.

From: Tetsuhiro Kohada
Date: Thu Jan 30 2020 - 02:07:49 EST

remove 'vol_type' variable.

The following issues are described in exfat's TODO.
> clean up the remaining vol_type checks, which are of two types:
> some are ?: operators with magic numbers, and the rest are places
> where we're doing stuff with '.' and '..'.

The vol_type variable is always set to 'EXFAT'.
The variable checks are unnessesary, so remove unused code.

Signed-off-by: Tetsuhiro Kohada <Kohada.Tetsuhiro@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
Reviewed-by: Mori Takahiro <Mori.Takahiro@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
Suggested-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
Changes in v2:
- Remove wrong check in exfat_readdir(), as suggested by Dan Carpenter.
- Update comment in exfat_readdir().

drivers/staging/exfat/exfat.h | 1 -
drivers/staging/exfat/exfat_core.c | 26 +++----------
drivers/staging/exfat/exfat_super.c | 60 ++++++++++-------------------
3 files changed, 27 insertions(+), 60 deletions(-)

diff --git a/drivers/staging/exfat/exfat.h b/drivers/staging/exfat/exfat.h
index 4d87360fab35..28d245b10e82 100644
--- a/drivers/staging/exfat/exfat.h
+++ b/drivers/staging/exfat/exfat.h
@@ -518,7 +518,6 @@ struct buf_cache_t {

struct fs_info_t {
u32 drv; /* drive ID */
- u32 vol_type; /* volume FAT type */
u32 vol_id; /* volume serial number */

u64 num_sectors; /* num of sectors in volume */
diff --git a/drivers/staging/exfat/exfat_core.c b/drivers/staging/exfat/exfat_core.c
index 07b460d01334..5a686289a1db 100644
--- a/drivers/staging/exfat/exfat_core.c
+++ b/drivers/staging/exfat/exfat_core.c
@@ -1560,11 +1560,7 @@ static s32 search_deleted_or_unused_entry(struct super_block *sb,
if (num_empty >= num_entries) {
p_fs->hint_uentry.dir = CLUSTER_32(~0);
p_fs->hint_uentry.entry = -1;
-
- if (p_fs->vol_type == EXFAT)
- return dentry - (num_entries - 1);
- else
- return dentry;
+ return dentry - (num_entries - 1);
}
}

@@ -1914,7 +1910,7 @@ s32 count_dos_name_entries(struct super_block *sb, struct chain_t *p_dir,

bool is_dir_empty(struct super_block *sb, struct chain_t *p_dir)
{
- int i, count = 0;
+ int i;
s32 dentries_per_clu;
u32 type;
struct chain_t clu;
@@ -1943,15 +1939,7 @@ bool is_dir_empty(struct super_block *sb, struct chain_t *p_dir)

if (type == TYPE_UNUSED)
return true;
- if ((type != TYPE_FILE) && (type != TYPE_DIR))
- continue;
-
- if (p_dir->dir == CLUSTER_32(0)) /* FAT16 root_dir */
- return false;
-
- if (p_fs->vol_type == EXFAT)
- return false;
- if ((p_dir->dir == p_fs->root_dir) || ((++count) > 2))
+ if ((type == TYPE_FILE) || (type == TYPE_DIR))
return false;
}

@@ -2128,7 +2116,6 @@ s32 exfat_mount(struct super_block *sb, struct pbr_sector_t *p_pbr)
p_fs->num_clusters = GET32(p_bpb->clu_count) + 2;
/* because the cluster index starts with 2 */

- p_fs->vol_type = EXFAT;
p_fs->vol_id = GET32(p_bpb->vol_serial);

p_fs->root_dir = GET32(p_bpb->root_cluster);
@@ -2165,7 +2152,7 @@ s32 create_dir(struct inode *inode, struct chain_t *p_dir,

clu.dir = CLUSTER_32(~0);
clu.size = 0;
- clu.flags = (p_fs->vol_type == EXFAT) ? 0x03 : 0x01;
+ clu.flags = 0x03;

/* (1) allocate a cluster */
ret = exfat_alloc_cluster(sb, 1, &clu);
@@ -2198,7 +2185,7 @@ s32 create_dir(struct inode *inode, struct chain_t *p_dir,
fid->entry = dentry;

fid->attr = ATTR_SUBDIR;
- fid->flags = (p_fs->vol_type == EXFAT) ? 0x03 : 0x01;
+ fid->flags = 0x03;
fid->size = size;
fid->start_clu = clu.dir;

@@ -2215,7 +2202,6 @@ s32 create_file(struct inode *inode, struct chain_t *p_dir,
s32 ret, dentry, num_entries;
struct dos_name_t dos_name;
struct super_block *sb = inode->i_sb;
- struct fs_info_t *p_fs = &(EXFAT_SB(sb)->fs_info);

ret = get_num_entries_and_dos_name(sb, p_dir, p_uniname, &num_entries,
&dos_name);
@@ -2247,7 +2233,7 @@ s32 create_file(struct inode *inode, struct chain_t *p_dir,
fid->entry = dentry;

fid->attr = ATTR_ARCHIVE | mode;
- fid->flags = (p_fs->vol_type == EXFAT) ? 0x03 : 0x01;
+ fid->flags = 0x03;
fid->size = 0;
fid->start_clu = CLUSTER_32(~0);

diff --git a/drivers/staging/exfat/exfat_super.c b/drivers/staging/exfat/exfat_super.c
index b81d2a87b82e..da4ee387b70b 100644
--- a/drivers/staging/exfat/exfat_super.c
+++ b/drivers/staging/exfat/exfat_super.c
@@ -494,7 +494,7 @@ static int ffsGetVolInfo(struct super_block *sb, struct vol_info_t *info)
if (p_fs->used_clusters == UINT_MAX)
p_fs->used_clusters = exfat_count_used_clusters(sb);

- info->FatType = p_fs->vol_type;
+ info->FatType = EXFAT;
info->ClusterSize = p_fs->cluster_size;
info->NumClusters = p_fs->num_clusters - 2; /* clu 0 & 1 */
info->UsedClusters = p_fs->used_clusters;
@@ -602,7 +602,7 @@ static int ffsLookupFile(struct inode *inode, char *path, struct file_id_t *fid)

fid->size = exfat_get_entry_size(ep2);
if ((fid->type == TYPE_FILE) && (fid->size == 0)) {
- fid->flags = (p_fs->vol_type == EXFAT) ? 0x03 : 0x01;
+ fid->flags = 0x03;
fid->start_clu = CLUSTER_32(~0);
} else {
fid->flags = exfat_get_entry_flag(ep2);
@@ -1095,7 +1095,7 @@ static int ffsTruncateFile(struct inode *inode, u64 old_size, u64 new_size)
fid->size = new_size;
fid->attr |= ATTR_ARCHIVE;
if (new_size == 0) {
- fid->flags = (p_fs->vol_type == EXFAT) ? 0x03 : 0x01;
+ fid->flags = 0x03;
fid->start_clu = CLUSTER_32(~0);
}

@@ -1203,14 +1203,6 @@ static int ffsMoveFile(struct inode *old_parent_inode, struct file_id_t *fid,

dentry = fid->entry;

- /* check if the old file is "." or ".." */
- if (p_fs->vol_type != EXFAT) {
- if ((olddir.dir != p_fs->root_dir) && (dentry < 2)) {
- ret = -EPERM;
- goto out2;
- }
- }
-
ep = get_entry_in_dir(sb, &olddir, dentry, NULL);
if (!ep) {
ret = -ENOENT;
@@ -1342,7 +1334,7 @@ static int ffsRemoveFile(struct inode *inode, struct file_id_t *fid)

fid->size = 0;
fid->start_clu = CLUSTER_32(~0);
- fid->flags = (p_fs->vol_type == EXFAT) ? 0x03 : 0x01;
+ fid->flags = 0x03;

#ifndef CONFIG_STAGING_EXFAT_DELAYED_SYNC
fs_sync(sb, true);
@@ -2020,12 +2012,6 @@ static int ffsRemoveDir(struct inode *inode, struct file_id_t *fid)

dentry = fid->entry;

- /* check if the file is "." or ".." */
- if (p_fs->vol_type != EXFAT) {
- if ((dir.dir != p_fs->root_dir) && (dentry < 2))
- return -EPERM;
- }
-
/* acquire the lock for file system critical section */
mutex_lock(&p_fs->v_mutex);

@@ -2048,7 +2034,7 @@ static int ffsRemoveDir(struct inode *inode, struct file_id_t *fid)

fid->size = 0;
fid->start_clu = CLUSTER_32(~0);
- fid->flags = (p_fs->vol_type == EXFAT) ? 0x03 : 0x01;
+ fid->flags = 0x03;

#ifndef CONFIG_STAGING_EXFAT_DELAYED_SYNC
fs_sync(sb, true);
@@ -2073,8 +2059,6 @@ static int exfat_readdir(struct file *filp, struct dir_context *ctx)
{
struct inode *inode = file_inode(filp);
struct super_block *sb = inode->i_sb;
- struct exfat_sb_info *sbi = EXFAT_SB(sb);
- struct fs_info_t *p_fs = &sbi->fs_info;
struct bd_info_t *p_bd = &(EXFAT_SB(sb)->bd_info);
struct dir_entry_t de;
unsigned long inum;
@@ -2084,24 +2068,22 @@ static int exfat_readdir(struct file *filp, struct dir_context *ctx)
__lock_super(sb);

cpos = ctx->pos;
- /* Fake . and .. for the root directory. */
- if ((p_fs->vol_type == EXFAT) || (inode->i_ino == EXFAT_ROOT_INO)) {
- while (cpos < 2) {
- if (inode->i_ino == EXFAT_ROOT_INO)
- inum = EXFAT_ROOT_INO;
- else if (cpos == 0)
- inum = inode->i_ino;
- else /* (cpos == 1) */
- inum = parent_ino(filp->f_path.dentry);
-
- if (!dir_emit_dots(filp, ctx))
- goto out;
- cpos++;
- ctx->pos++;
- }
- if (cpos == 2)
- cpos = 0;
+ /* Fake . and .. for any directory. */
+ while (cpos < 2) {
+ if (inode->i_ino == EXFAT_ROOT_INO)
+ inum = EXFAT_ROOT_INO;
+ else if (cpos == 0)
+ inum = inode->i_ino;
+ else /* (cpos == 1) */
+ inum = parent_ino(filp->f_path.dentry);
+
+ if (!dir_emit_dots(filp, ctx))
+ goto out;
+ cpos++;
+ ctx->pos++;
}
+ if (cpos == 2)
+ cpos = 0;
if (cpos & (DENTRY_SIZE - 1)) {
err = -ENOENT;
goto out;
@@ -3345,7 +3327,7 @@ static int exfat_statfs(struct dentry *dentry, struct kstatfs *buf)
return -EIO;

} else {
- info.FatType = p_fs->vol_type;
+ info.FatType = EXFAT;
info.ClusterSize = p_fs->cluster_size;
info.NumClusters = p_fs->num_clusters - 2;
info.UsedClusters = p_fs->used_clusters;
--
2.25.0