renegade-project/linux-next
2
0
Fork 0
mirror of https://github.com/edk2-porting/linux-next.git synced 2025-01-10 14:43:54 +08:00
Code

drivers/staging/exfat: Replace more binary semaphores with mutexes

Browse Source 
At a slight footprint cost (24 vs 32 bytes), mutexes are more optimal
than semaphores; it's also a nicer interface for mutual exclusion,
which is why they are encouraged over binary semaphores, when possible.
There is also lockdep support.

For both f_sem and b_sem, their semantics imply traditional lock
ownership; that is, the lock owner is the same for both lock/unlock
operations and not under irq contexts (ie for trylock/unlock scenarios).
Therefore it is safe to convert.

Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Link: https://lore.kernel.org/r/20191101185332.31786-1-dave@stgolabs.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Davidlohr Bueso 2019-11-01 11:53:32 -07:00 committed by Greg Kroah-Hartman
parent 8823d99080
commit 74179976b0
1 changed files with 24 additions and 24 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

48
drivers/staging/exfat/exfat_cache.c
View File

@ -12,8 +12,8 @@
#define DIRTYBIT 0x02
/* Local variables */
static DEFINE_SEMAPHORE(f_sem);
static DEFINE_SEMAPHORE(b_sem);
static DEFINE_MUTEX(f_mutex);
static DEFINE_MUTEX(b_mutex);
static struct buf_cache_t *FAT_cache_find(struct super_block *sb, sector_t sec)
{
@ -315,9 +315,9 @@ int FAT_read(struct super_block *sb, u32 loc, u32 *content)
{
s32 ret;
down(&f_sem);
mutex_lock(&f_mutex);
ret = __FAT_read(sb, loc, content);
up(&f_sem);
mutex_unlock(&f_mutex);
return ret;
}
@ -434,9 +434,9 @@ int FAT_write(struct super_block *sb, u32 loc, u32 content)
{
s32 ret;
down(&f_sem);
mutex_lock(&f_mutex);
ret = __FAT_write(sb, loc, content);
up(&f_sem);
mutex_unlock(&f_mutex);
return ret;
}
@ -490,7 +490,7 @@ void FAT_release_all(struct super_block *sb)
struct buf_cache_t *bp;
struct fs_info_t *p_fs = &(EXFAT_SB(sb)->fs_info);
down(&f_sem);
mutex_lock(&f_mutex);
bp = p_fs->FAT_cache_lru_list.next;
while (bp != &p_fs->FAT_cache_lru_list) {
@ -507,7 +507,7 @@ void FAT_release_all(struct super_block *sb)
bp = bp->next;
}
up(&f_sem);
mutex_unlock(&f_mutex);
}
void FAT_sync(struct super_block *sb)
@ -515,7 +515,7 @@ void FAT_sync(struct super_block *sb)
struct buf_cache_t *bp;
struct fs_info_t *p_fs = &(EXFAT_SB(sb)->fs_info);
down(&f_sem);
mutex_lock(&f_mutex);
bp = p_fs->FAT_cache_lru_list.next;
while (bp != &p_fs->FAT_cache_lru_list) {
@ -526,7 +526,7 @@ void FAT_sync(struct super_block *sb)
bp = bp->next;
}
up(&f_sem);
mutex_unlock(&f_mutex);
}
static struct buf_cache_t *buf_cache_find(struct super_block *sb, sector_t sec)
@ -600,9 +600,9 @@ u8 *buf_getblk(struct super_block *sb, sector_t sec)
{
u8 *buf;
down(&b_sem);
mutex_lock(&b_mutex);
buf = __buf_getblk(sb, sec);
up(&b_sem);
mutex_unlock(&b_mutex);
return buf;
}
@ -611,7 +611,7 @@ void buf_modify(struct super_block *sb, sector_t sec)
{
struct buf_cache_t *bp;
down(&b_sem);
mutex_lock(&b_mutex);
bp = buf_cache_find(sb, sec);
if (likely(bp))
@ -620,14 +620,14 @@ void buf_modify(struct super_block *sb, sector_t sec)
WARN(!bp, "[EXFAT] failed to find buffer_cache(sector:%llu).\n",
(unsigned long long)sec);
up(&b_sem);
mutex_unlock(&b_mutex);
}
void buf_lock(struct super_block *sb, sector_t sec)
{
struct buf_cache_t *bp;
down(&b_sem);
mutex_lock(&b_mutex);
bp = buf_cache_find(sb, sec);
if (likely(bp))
@ -636,14 +636,14 @@ void buf_lock(struct super_block *sb, sector_t sec)
WARN(!bp, "[EXFAT] failed to find buffer_cache(sector:%llu).\n",
(unsigned long long)sec);
up(&b_sem);
mutex_unlock(&b_mutex);
}
void buf_unlock(struct super_block *sb, sector_t sec)
{
struct buf_cache_t *bp;
down(&b_sem);
mutex_lock(&b_mutex);
bp = buf_cache_find(sb, sec);
if (likely(bp))
@ -652,7 +652,7 @@ void buf_unlock(struct super_block *sb, sector_t sec)
WARN(!bp, "[EXFAT] failed to find buffer_cache(sector:%llu).\n",
(unsigned long long)sec);
up(&b_sem);
mutex_unlock(&b_mutex);
}
void buf_release(struct super_block *sb, sector_t sec)
@ -660,7 +660,7 @@ void buf_release(struct super_block *sb, sector_t sec)
struct buf_cache_t *bp;
struct fs_info_t *p_fs = &(EXFAT_SB(sb)->fs_info);
down(&b_sem);
mutex_lock(&b_mutex);
bp = buf_cache_find(sb, sec);
if (likely(bp)) {
@ -676,7 +676,7 @@ void buf_release(struct super_block *sb, sector_t sec)
move_to_lru(bp, &p_fs->buf_cache_lru_list);
}
up(&b_sem);
mutex_unlock(&b_mutex);
}
void buf_release_all(struct super_block *sb)
@ -684,7 +684,7 @@ void buf_release_all(struct super_block *sb)
struct buf_cache_t *bp;
struct fs_info_t *p_fs = &(EXFAT_SB(sb)->fs_info);
down(&b_sem);
mutex_lock(&b_mutex);
bp = p_fs->buf_cache_lru_list.next;
while (bp != &p_fs->buf_cache_lru_list) {
@ -701,7 +701,7 @@ void buf_release_all(struct super_block *sb)
bp = bp->next;
}
up(&b_sem);
mutex_unlock(&b_mutex);
}
void buf_sync(struct super_block *sb)
@ -709,7 +709,7 @@ void buf_sync(struct super_block *sb)
struct buf_cache_t *bp;
struct fs_info_t *p_fs = &(EXFAT_SB(sb)->fs_info);
down(&b_sem);
mutex_lock(&b_mutex);
bp = p_fs->buf_cache_lru_list.next;
while (bp != &p_fs->buf_cache_lru_list) {
@ -720,5 +720,5 @@ void buf_sync(struct super_block *sb)
bp = bp->next;
}
up(&b_sem);
mutex_unlock(&b_mutex);
}