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Subject[PATCH 1/2] staging: dgnc: remove dead code in dgnc_tty_write()
Date
Remove the dead code protected by in_user in dgnc_tty_write() because it is set
to 0 and never changed to 1 thus the code in ifs never gets executed.

Signed-off-by: Giedrius Statkevičius <giedrius.statkevicius@gmail.com>
---
v2: Just remove the dead code protected by in_user and join the first and third
patches.

drivers/staging/dgnc/dgnc_tty.c | 45 +----------------------------------------
1 file changed, 1 insertion(+), 44 deletions(-)

diff --git a/drivers/staging/dgnc/dgnc_tty.c b/drivers/staging/dgnc/dgnc_tty.c
index ce4187f..cf2eb21 100644
--- a/drivers/staging/dgnc/dgnc_tty.c
+++ b/drivers/staging/dgnc/dgnc_tty.c
@@ -42,16 +42,11 @@
#include "dgnc_sysfs.h"
#include "dgnc_utils.h"

-#define init_MUTEX(sem) sema_init(sem, 1)
-#define DECLARE_MUTEX(name) \
- struct semaphore name = __SEMAPHORE_INITIALIZER(name, 1)
-
/*
* internal variables
*/
static struct dgnc_board *dgnc_BoardsByMajor[256];
static unsigned char *dgnc_TmpWriteBuf;
-static DECLARE_MUTEX(dgnc_TmpWriteSem);

/*
* Default transparent print information.
@@ -1705,7 +1700,6 @@ static int dgnc_tty_write(struct tty_struct *tty,
ushort tail;
ushort tmask;
uint remain;
- int from_user = 0;

if (tty == NULL || dgnc_TmpWriteBuf == NULL)
return 0;
@@ -1785,38 +1779,6 @@ static int dgnc_tty_write(struct tty_struct *tty,
if (count <= 0)
goto exit_retry;

- if (from_user) {
-
- count = min(count, WRITEBUFLEN);
-
- spin_unlock_irqrestore(&ch->ch_lock, flags);
-
- /*
- * If data is coming from user space, copy it into a temporary
- * buffer so we don't get swapped out while doing the copy to
- * the board.
- */
- /* we're allowed to block if it's from_user */
- if (down_interruptible(&dgnc_TmpWriteSem))
- return -EINTR;
-
- /*
- * copy_from_user() returns the number
- * of bytes that could *NOT* be copied.
- */
- count -= copy_from_user(dgnc_TmpWriteBuf, (const unsigned char __user *) buf, count);
-
- if (!count) {
- up(&dgnc_TmpWriteSem);
- return -EFAULT;
- }
-
- spin_lock_irqsave(&ch->ch_lock, flags);
-
- buf = dgnc_TmpWriteBuf;
-
- }
-
n = count;

/*
@@ -1853,12 +1815,7 @@ static int dgnc_tty_write(struct tty_struct *tty,
ch->ch_cpstime += (HZ * count) / ch->ch_digi.digi_maxcps;
}

- if (from_user) {
- spin_unlock_irqrestore(&ch->ch_lock, flags);
- up(&dgnc_TmpWriteSem);
- } else {
- spin_unlock_irqrestore(&ch->ch_lock, flags);
- }
+ spin_unlock_irqrestore(&ch->ch_lock, flags);

if (count) {
/*
--
2.3.5


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