sys_swapon: remove did_down variable

Since mutex_lock(&inode->i_mutex) is called just after setting inode,
did_down is always equivalent to (inode && S_ISREG(inode->i_mode)).

Use this fact to remove the did_down variable.

Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net>
Tested-by: Eric B Munson <emunson@mgebm.net>
Acked-by: Eric B Munson <emunson@mgebm.net>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Cesar Eduardo Barros 2011-03-22 16:33:21 -07:00 committed by Linus Torvalds
parent 28b36bd741
commit 83ef99befc

View File

@ -1907,7 +1907,6 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
unsigned char *swap_map = NULL;
struct page *page = NULL;
struct inode *inode = NULL;
int did_down = 0;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
@ -1962,7 +1961,6 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
} else if (S_ISREG(inode->i_mode)) {
p->bdev = inode->i_sb->s_bdev;
mutex_lock(&inode->i_mutex);
did_down = 1;
if (IS_SWAPFILE(inode)) {
error = -EBUSY;
goto bad_swap;
@ -2154,10 +2152,8 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
spin_unlock(&swap_lock);
vfree(swap_map);
if (swap_file) {
if (did_down) {
if (inode && S_ISREG(inode->i_mode))
mutex_unlock(&inode->i_mutex);
did_down = 0;
}
filp_close(swap_file, NULL);
}
out:
@ -2167,7 +2163,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
}
if (name)
putname(name);
if (did_down) {
if (inode && S_ISREG(inode->i_mode)) {
if (!error)
inode->i_flags |= S_SWAPFILE;
mutex_unlock(&inode->i_mutex);